EPA Superfund
Record of Decision:
PB99-964304
EPA541-R99-073
1999
Ralston Site
Cedar Rapids, IA
9/30/1999
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RECORD OF DECISION
RALSTON SITE
CEDAR RAPIDS, IOWA
Prepared by:
U.S. Environmental Protection Agency
Region VII
901 North 5th Street
Kansas City, Kansas 66101
September 1999
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RECORD OF DECISION
DECLARATION
SITE NAME AND LOCATION
Ralston Site
Cedar Rapids, Iowa
STATEMENT OF BASIS AND PURPOSE
The U.S. Environmental Protection Agency (EPA) has prepared this decision document
to present the selected remedial action for the Ralston site located in Cedar Rapids, Iowa. This
decision was chosen in accordance with the Comprehensive Environmental Response,
Compensation and Liability Act (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act (SARA), and to the extent practicable, the National Contingency Plan
(NCP). This decision is based on the Administrative Record for this site. The Administrative
Record file is located in the following information repositories:
Cedar Rapids Public Library U.S. Environmental Protection Agency
500 1st Street S.E. 901 North 5th Street
Cedar Rapids, Iowa Kansas City, Kansas
The EPA has coordinated selection of this remedial action with the Iowa Department of
Natural Resources. The state of Iowa concurs with the selected remedy.
ASSESSMENT OF THE SITE
The response action selection in the Record of Decision (ROD) is necessary to protect the
public health or welfare or the environment from actual or threatened releases of hazardous
substances into the environment.
DESCRIPTION OF THE SELECTED REMEDY
The selected remedy prevents exposure to contaminated ground water, restores the
ground water to drinking water quality outside of the disposal area, and maintains site conditions
which prevent exposure to contaminated soil. The selected remedy includes the following
components:
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• Monitored natural attenuation of ground water;
• Continued ownership of the fenced-in area, including the disposal area;
• Continued listing of the site on the Registry of Hazardous Waste or Hazardous
Substance Disposal Sites pursuant to Iowa Administrative Code 455B.426;
• Continued designation of a protected ground water source area surrounding the
site pursuant to Iowa Administrative Code 567-53.7(4558);
• Maintenance of the disposal area cap; and
• Maintenance of the Dry Run Creek bank stabilization.
In order to accelerate the cleanup of the disposal area, a removal action was completed. It
included capping of the former disposal area; stabilizing the bank of Dry Run Creek; installation
and operation of a dual vapor extraction and treatment system, which resulted in the removal and
treatment of more than 4,800 pounds of volatile organic compounds; extraction and treatment of
shallow ground water north of Dry Run Creek; and implementation of institutional and
engineering controls.
The selected remedy continues to prevent exposure to contaminated soil through
maintenance of the cap and creek bank stabilization and the implementation of institutional
controls. The selected remedy prevents exposure to contaminated ground water through
monitored natural attenuation continuing to decrease the concentrations of the contaminants and
controlling the withdrawal of ground water in the protected source area.
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, complies with
federal and state requirements that are applicable or relevant and appropriate to the remedial
action, is cost-effective, and utilizes permanent solutions and alternative treatment technologies
to the maximum extent possible. Treatment of the ground water was not found to be practical;
therefore, this remedy does not satisfy the statutory preference for treatment as a principal
element of the remedy.
Because this remedy will result in hazardous substances remaining on site above levels
that allow for unlimited use and unrestricted exposure, a review will be conducted within five
years after initiation of remedial action to ensure that the remedy continues to provide adequate
protection of human health and the environment.
ROD DATA CERTIFICATION CHECKLIST
The following information is included in the Decision Summary section of this Record of
Decision. Additional information can be found in the Administrative Record file for this site.
• Chemicals of concern (COCs) and their respective concentrations
Baseline risk represented by the COCs
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Cleanup levels established for COCs and the basis for the levels
Current and future land and ground water use assumptions used in the baseline risk
assessment and the ROD
Land and ground water use that will be available at the site as a result of the selected
remedy
Estimated capital, operation and maintenance, and total present worth costs; discount
rate; and the number of years over which the remedy cost estimates are projected
Decisive factors that led to selecting the remedy
, „
Michael J. Sanderson
Director
Superfund Division
U.S. EPA, Region VII
Date
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RECORD OF DECISION
DECISION SUMMARY
1.0 Site Name, Location, and Description
This Record of Decision (ROD) has been developed by the United States Environmental
Protection Agency (EPA) to select a remedial alternative at the Ralston site in Cedar Rapids,
Iowa (herein, the "Site"). The Comprehensive Environmental Response, Compensation, and
Liability Information System (CERCLIS) identification number for the site is IAD980632491.
The EPA is the lead agency for enforcement of the activities taking place at the Ralston site and
Rockwell Collins Inc. (Rockwell) is the responsible party conducting the work at the site.
The Ralston site is located north of 228 Blairs Ferry Road in northern Cedar Rapids,
Iowa. Access to the site is by way of a gravel road north of Blairs Ferry Road. A V/2 acre
portion of the site is referred to as the "source area" because this is where the disposal activities
occurred. Figure 1 is a map of the Ralston site, including the location of monitoring wells.
From about 1956 to 1958, the Ralston site was used by Rockwell as a disposal area for
wastes generated from a pilot gold-plating operation and other industrial sources. The amount of
solid and liquid wastes that were disposed at the site is not known; however, it has been
estimated that 60,000 gallons of liquid waste may have been disposed of during the years of
plating operation. The wastes were typically burned and spread in layers, as necessary, to
accommodate additional wastes. The types of wastes disposed at the site by Rockwell included
solvents, paint sludge, and general industrial refuse, including scrap metal, office furniture, and
construction and demolition debris. The Ralston disposal site was not restricted solely for
Rockwell use and other local businesses or citizens likely disposed of other solid waste at the
site.
In addition to the industrial-type wastes already mentioned, the Ralston site was also used
for the disposal of cyanide waste (salts of ferrocyanide compounds) from the plating operation.
The cyanide wastes were initially placed in 5-gallon containers. Two 5-gallon containers were
then placed in a 55-gallon drum and encapsulated in concrete. An undetermined number of
concrete-encapsulated cyanide drums were disposed at the site.
2.0 Site History and Enforcement Activities
In December 1981, Rockwell submitted a Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) Section 103(c) notice to the EPA which listed
hazardous substances disposed at the Ralston site as solvents, paint sludge, and buried drums of
concrete-encapsulated cyanide. Rockwell estimated that 60, 000 gallons of liquid wastes were
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generated and disposed of during the years of its plating operation, and an undetermined number
of concrete-encapsulated cyanide drums were buried at the site.
In May 1985, a contractor for the EPA conducted a preliminary assessment of the Ralston
site. The assessment indicated that ground water and surface water contamination may have
resulted from the previous disposal activities and a site inspection was recommended.
In 1989, Rockwell removed and properly disposed of two drums of concrete-encapsulated
cyanide. No other drums were located.
In November 1990, Rockwell conducted additional investigation at the site under the
oversight of an EPA contractor. Six trenches were excavated and shallow soil borings were
installed on a 50-foot by 50-foot grid system for the purpose of collecting soil samples for
laboratory analyses of volatile organic compounds (VOCs) and metals. The results of this
investigation were reported in a document entitled "Report for Investigation of the Ralston Site,
Blairs Ferry Road, January 1991."
On December 4, 1991, Rockwell and the EPA, Region 7, entered into an Administrative
Order on Consent to conduct a Remedial Investigation and Feasibility Study (RI/FS) at the
Ralston site. The goal of the RI/FS was to investigate the extent of soil and ground water
contamination at the site and to determine an appropriate remedy or remedies.
In order to accelerate the cleanup of the disposal area and shallow ground water, on
January 22,1993, Rockwell and the EPA entered into a second Administrative Order on Consent
to conduct a Removal Site Evaluation, Engineering Evaluation/Cost Analysis (EE/CA), and a
removal action. The removal action took place while work continued on the RI/FS.
The removal actions implemented at the Ralston site included the following:
• Capping of the former disposal area;
Stabilizing the bank of Dry Run Creek to prevent erosion at the site;
Installation and operation of a dual vapor extraction (DVE) and treatment system; and
Extracting and treating alluvial (shallow) ground water located north of Dry Run Creek.
Capping of the disposal area and stabilization of the creek bank were completed in
December 1995. The DVE system began full-time operation in April 1995 and operated
periodically until June 1997, at which time it was determined that it was no longer effectively
removing more of the source contamination. More than 4,800 pounds of VOCs were removed
and treated with the DVE and treatment system.
The RI Report and other documents in the Administrative Record file may be reviewed
for a more complete source of information regarding the history of the site.
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3.0 Community Participation
Throughout the time that investigation and removal activities have taken place at the site,
numerous community involvement activities have occurred. These include the distribution of
fact sheets, meetings with the public, and media interviews. The EE/C A was made available for
public comment in 1994, prior to the EPA making a final decision regarding the removal action.
A Community Relations Plan was prepared for the site in 1994 as well.
The EPA issued a Proposed Plan for the Ralston site on June 15,1999. A 30-day public
comment period occurred from July 1 to August 2,1999. A public meeting was held on
July 6, 1999, at the Cedar Rapids Water Department in Cedar Rapids, Iowa, to present the
Proposed Plan and solicit comments from the public. Additionally, the EPA established an
Administrative Record which contains supportive documents for this decision. The
Administrative Record is available for review during normal business hours at the following
locations:
Cedar Rapids Public Library U.S. Environmental Protection Agency
500 1st Street S.E. 901 N. 5th Street
Cedar Rapids, Iowa Kansas City, Kansas
4.0 Scope and Role of Response Action
During the RI, a removal action was conducted to accelerate the clean up of the soil and
shallow ground water in the vicinity of the disposal area. All of the work associated with the
removal action was completed in 1997.
The remedy selected in this ROD is the only remedial action planned for this site. This
remedial action includes components to ensure that steps taken during the removal action
continue to be protective. Specifically, measures are included to ensure that the disposal area cap
and creek bank stabilization are maintained and that institutional controls, which have been
initiated, remain in place.
5.0 Site Characteristics
The Ralston site is located north of 228 Blairs Ferry Road in northern Cedar Rapids, Linn
County, Iowa. The disposal area occupies 1V* acres and is enclosed with a fence.
The topography of the disposal area is characterized by the steeply sloping banks of Dry
Run Creek to the north and a railroad embankment to the south. The removal actions discussed
previously have modified the general site topography by raising and leveling the disposal area.
A minimum of two feet of compacted clay and two feet of topsoil were placed as a cap over the
surface of the former disposal area to prevent precipitation infiltration. Terraces, drainage
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channels, and an access road were subsequently constructed on top of the cap to prevent cap
erosion and improve access.
The topography of the southern creek bank of Dry Run Creek, which forms the northern
boundary of the disposal area, was also modified by removal actions implemented at the site. A
total of 13,400 square feet of geomembrane liner and 17,840 square feet of cable-concrete mats
were placed on the creek bank to protect the site and clay cap from surface water erosion
associated with the creek. Cable-concrete mats were also placed under the creek crossing to
provide a resistant and stable surface upon which to cross the creek.
The geology of the site vicinity generally consists of unconsolidated Quaternary-age
alluvial deposits overlying Devonian and Silurian carbonate bedrock. Unconsolidated deposits at
the site near Dry Run Creek consist of a thin layer of topsoil and clayey to sandy silt overlying
fine to medium sand.
Three principal aquifers are present at the site: 1) the Quaternary alluvial aquifer; 2) the
Devonian aquifer; and 3) the Silurian aquifer. The alluvial aquifer at the Ralston site is
approximately 10 feet to 15 feet thick and consists of ground water flow in the alluvial sands and
gravel near Dry Run Creek. Under normal conditions, shallow ground water flow from the
disposal area is oriented primarily to the northeast toward the creek. North of the disposal area,
shallow ground water flow is radially southward from upland areas toward the channel of Dry
Run Creek.
At a depth below the ground surface of approximately 20 to 50 feet, Devonian-age
dolomite bedrock of the Otis and Bertram formations is encountered. In the Devonian aquifer
the ground water flow is in both the northeast and southeast directions from the site.
The Silurian-age Scotch Grove formation is encountered throughout the site vicinity at a
depth below the ground surface of approximately 110 to 140 feet. Ground water flow in the
Silurian aquifer is predominantly horizontal with little or no component of vertical ground water
flow. The horizontal direction of ground water flow is generally southward with some variation.
Downward vertical gradients were measured between nested wells installed in the
alluvial, Devonian, and Silurian aquifers. Near the creek channel, more pronounced vertical
solution weathering in the bedrock aquifers may indicate an area of increased downward
migration of contaminants.
Several private and public water supply wells exist within two miles of the site. Six
private wells within one mile of the site have been sampled on a routine basis since RI activities
began. Available well construction information indicates most of these water-supply wells are
greater than 150 feet deep, cased through the unconsolidated and upper bedrock deposits, and are
open to lower Devonian and/or Silurian rocks. The city of Marion utilizes two wells which tap
the Silurian aquifer approximately one mile east of the Ralston site.
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The RI for the Ralston site was conducted using a phased approach. Between 1992 and
1996, five phases of investigation were conducted at the site. The results of the first two phases
indicated that soil and ground water contamination existed above the bedrock surface in the
disposal area, and shallow ground water contamination extended north of the site. In order to
accelerate remediation of the disposal area and shallow ground water, Rockwell agreed to
perform the Removal Site Evaluation, EE/CA, and removal action mentioned previously, while
continuing to investigate the extent of ground water contamination in the bedrock aquifer.
Concurrent with the removal activities, the nature and extent of ground water contamination in
the underlying Devonian and Silurian aquifers was characterized during RI Phases 3, 4, and 5.
Soil and ground water contaminants detected at the site have been attributed to historical
disposal of solvents and other wastes at the site. The primary contaminants at the site which
pose a threat to ground water are chlorinated VOCs. The VOCs found at the site include
trichloroethene (TCE) and its associated degradation products cis-l,2-dichloroethene (cis-1,2-
DCE) and vinyl chloride. The VOCs are detected in three primary zones: the alluvial shallow
soil and ground water; the Devonian aquifer, and the Silurian aquifer. The highest
concentrations of VOCs were historically detected in shallow ground water in the disposal area.
Elevated concentrations have also been detected in the two bedrock water-bearing zones. The
highest concentrations in the Devonian aquifer include TCE at 2200 micrograms per liter Cug/L),
cis-l,2-DCE at 4800 //g/L, and vinyl chloride at 2100 ^g/L. The highest concentrations in the
Silurian aquifer have been detected in a low-permeability layer that is somewhat hydraulically
isolated from other zones. Contaminants detected include cis-l,2-DCE at 73,200 //g/L and vinyl
chloride at 9000 /wg/L. The VOCs in the Devonian and Silurian aquifers appear to extend
approximately 800 to 1000 feet downgradient of the disposal area. Periodic ground water
monitoring has indicated very little variation of concentrations in the two bedrock zones and,
accordingly, the plume is considered to be at steady-state. Ground water monitoring began in
1992 and continued throughout the RI.
During the course of the investigations at the site information was gathered to determine
the extent to which natural attenuation of contaminants was occurring. Natural attenuation refers
to naturally occurring processes in the environment that act to reduce the mass, toxicity,
mobility, volume, or concentration of contaminants in various media. These in situ processes
include biodegradation, dispersion, dilution, adsorption, volatilization, and chemical or
biological stabilization or destruction of contaminants.
At the Ralston site, natural attenuation involves two main components: (1) physical
attenuation processes consisting primarily of aquifer dilution, dispersion, and diffusion; and (2)
intrinsic bioremediation. Intrinsic bioremediation is the process by which contaminants are
transformed from toxic to nontoxic by-products through biologically mediated reactions that
occur naturally in the ground water system. Whereas physical attenuation processes reduce the
contaminant concentrations and their overall toxicity in ground water, intrinsic bioremediation
includes biological and chemical processes that destroy contaminant mass in the aquifer. Loss of
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contaminant mass will reduce the volume of contaminants present and result in overall plume
shrinkage.
Data from the Ralston site indicates that intrinsic bioremediation is occurring in the
disposal area and areas downgradient in the alluvial, Devonian, and Silurian aquifers. Natural
attenuation is sufficient to cause a stable or shrinking plume. The data indicate that ground water
conditions are sufficiently anaerobic for reductive dechlorination of the contaminants of concern
to occur. Electron acceptors (dissolved oxygen, nitrate, manganese, iron, sulfate, and methane)
are depleted in areas of active biodegradation and other geochemical conditions are enriched
(chloride and alkalinity.) Data from the site indicates that much of the original TCE mass has
been degraded to cis-l,2-DCE, vinyl chloride, and ethene along the ground water flow pathways,
and these breakdown products, as well as inorganic chloride, form overlapping plumes in the
aquifer. The evaluation of intrinsic bioremediation at the Ralston site is discussed fully in the FS
Report, Appendix A, which is entitled "Evidence for Intrinsic Bioremediation at the Ralston
Site."
The high concentrations of VOCs that were found in the soil and ground water in the
disposal area during the RI suggest that some contaminants may be present in that area as dense
nonaqueous phase liquids (DNAPLs). A DNAPL is a chemical that is a liquid in its pure form
that is heavier than water and does not readily mix with water, but does slowly dissolve in water.
Residual DNAPL or elevated VOC concentrations adsorbed into site soil, or debris, are a
continuing source for release of VOCs to ground water. Ground water which comes in contact
with the waste materials in the disposal area is impacted by possible DNAPL contamination and
various contaminants of concern.
Elevated concentrations of some metals were found in samples taken from monitoring
wells in the disposal area during the first phase of investigation. Ground water samples were not
analyzed for metals during any subsequent phase of the investigation.
Six privately owned water wells near the Ralston site have also been sampled
periodically. Two of these private wells have exhibited detectable VOC concentrations. These
wells are no longer used as private drinking water supplies because the residences were
connected to a public water supply. No VOCs have been detected in any other private drinking
water supply wells. Concentrations in the two private wells which did exhibit contamination
have remained constant or decreasing over time, further indicating that the ground water
contamination plume is stable or decreasing.
The residential wells were sampled for metals during the first phase of the investigation.
Metals concentrations were not found in these wells at levels which posed a threat to human
health.
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A conceptual model of the site was developed to depict how contamination in the
disposal area has potentially led to the exposure of several receptor populations. This conceptual
model is illustrated in Figure 2.
During the course of the response actions taken to date at the Ralston site, institutional
and engineering controls have also been implemented. Institutional controls are non-engineering
methods intended to affect human activities in such a way as to prevent or reduce exposure to
hazardous substances. Engineering controls are physical barriers to exposure. The institutional
and engineering controls are expected to reduce the potential for contamination affecting current
or future receptors. These institutional and engineering controls greatly limit the excess risks
that additional actions need to address. The institutional controls include the following:
• New wells cannot be installed within a one-mile radius of the former disposal area
without approval by the Iowa Department of Natural Resources (IDNR);
The disposal area and immediate vicinity were purchased by Rockwell; and
The site has been listed on the State Abandoned or Uncontrolled Site Registry such that it
cannot be sold or transferred without the approval of the IDNR.
The following is an engineering control which has been implemented at the Ralston site:
All private residences with wells containing detectable levels of VOCs have been
connected to a public water supply.
6.0 Current and Potential Future Site and Resource Uses
6.1 Land Uses
The disposal area is fenced and will continue to be fenced. It is accessible through a
locked gate. Rockwell has stated that it will continue to own this property in the future and will
restrict access to the disposal area to those who have a need to monitor and maintain it.
The area immediately surrounding the disposal area is zoned for agricultural use. There
are commercial properties within 500 feet of the disposal area and residences within 1000 feet. It
is possible that there will be further commercial and residential development in areas outside of
the disposal area. The cities of Cedar Rapids and Marion, Iowa, are considering the future
development of a greenway that could pass outside of the disposal area.
6.2 Surface Water Uses
Surface water from the site flows north and discharges into Dry Run Creek. Dry Run
Creek is an intermittent stream that flows into Indian Creek about one-mile downstream and it in
turn flows into the Cedar River 111A miles downstream of the site. Indian Creek and the Cedar
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River are primarily used for recreational (fishing) purposes and golf course irrigation. It is not
anticipated that the uses will change.
6.3 Ground Water Uses
There are six private wells within one mile of the site but the two wells which have
exhibited detectable levels of VOCs are no longer used for drinking water. The other private
wells continue to be used for drinking water purposes. The city of Marion utilizes two wells
which tap the Silurian aquifer and are located approximately one mile east of the site. It is
anticipated that these ground water uses will not change in the future.
Since a one mile area around the site has been designated as a protected source area
pursuant to Iowa Administrative Code 567-53.7(4558), any changes to the use of ground water
in that area must be approved by the state.
It is the goal of the remedial action at this site to control exposure to, and prevent the
spread of, contamination. Ground water monitoring will be used to ensure that the remedy is
effective in addressing the contamination in the ground water. The goal of the remedy is to
restore the ground water to drinking water quality outside of the disposal area.
7.0 Summary of Site Risks
CERCLA requires the EPA to seek permanent solutions to protect human health and the
environment from hazardous substances to the extent practicable. These solutions provide for
removal, treatment, or containment of dangerous chemicals so that any remaining contamination
does not pose an unacceptable health risk to those who might come into contact with the
contaminants. Actual or threatened releases of hazardous substances from this site, if not
addressed by implementing the response action selected in this ROD, may present a current or
potential threat to public health, welfare, or the environment.
7.1 Summary of Human Health Risk Assessment
The baseline risk assessment estimates what risks the site poses if no action were taken.
It provides the basis for taking action and identifies the contaminants and exposure pathways that
need to be addressed by the remedial action. This section of the ROD summarizes the results of
the baseline risk assessment for this site.
The EPA prepared a baseline risk assessment using the data collected during the RI.
However, the report entitled Final Baseline Risk Assessment, dated October 21, 1994, was
completed before the removal actions and institutional controls were implemented at the site.
The Final Baseline Risk Assessment report may be found in the Administrative Record file.
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In general, the EPA requires or undertakes remedial actions for Superfund sites when the
excess carcinogenic (cancer) risk exceeds 10"4. A risk of 10"4 represents an increase of one in ten
thousand, or 1/10,000, for a reasonable maximum exposure (RME). This risk represents the
lifetime risk of developing cancer as a result of releases from the site.
Remedial actions may also be conducted at Superfund sites when the hazard index (HI)
equals or exceeds one for the RME scenario. The HI is a numeric expression of the
noncarcinogenic risk to human health resulting from releases from the site.
7.1.1 Identification of Chemicals of Concern
Tables 3.2 through 3.10 (attached) present chemicals of potential concern (COPCs) and
exposure point concentrations for each of the COPCs detected in each of the media sampled at
the site. These tables come from the Final Baseline Risk Assessment. The tables include the
range of concentrations detected for each COPC, as well as the frequency of detection (i.e., the
number of times the chemical was detected in the samples collected), the exposure point
concentration, and the 95% Upper Confidence Limit on the arithmetic mean of the
concentrations.
The COPCs were carried throughout the baseline risk calculations for this site; however,
the subset of these chemicals which drive the need to perform a remedial action are of primary
concern. They are referred to as the chemicals of concern (COC). As stated previously, a
removal action was implemented after the baseline risk assessment was prepared. As a result of
these actions and the implementation of institutional and engineering controls, the only
contaminated media which continues to pose an unacceptable level of threat is ground water.
The only COCs which will be discussed further in the section are the COCs for ground water.
The COCs in ground water include TCE and compounds commonly associated as TCE
degradation products. The TCE degradation products include cis-l,2-DCE and vinyl chloride.
Benzene and 1,1-dichloroethene are also COCs.
7.1.2 Exposure Assessment
The RME scenarios are developed using current exposure pathways given existing land
uses and also exposures which might reasonably be predicted based upon expected or logical
future land use assumptions. During preparation of the Final Baseline Risk Assessment for the
Ralston site there were three RME scenarios which were determined to be appropriate prior to
implementation of the removal action and the institutional and engineering controls. The RME
scenarios and the exposure pathways for each of these scenarios are as follows:
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RME Scenario I
Current land use for a 6- to 12-year-old trespasser
Ingestion of contaminants in surface soil, sediment, and surface water
Dermal absorption of contaminants in surface soil, sediment, and surface water
• Inhalation of contaminants in fugitive dust
RME Scenario 2
Current land use for an off site resident
• Inhalation of contaminants in fugitive dust
Ground water ingestion
Inhalation of vapors while showering
RME Scenario 3
Future land use for an on site resident
Ingestion of contaminants in surface soil, sediment, surface water, and ground water
Dermal absorption of contaminants in surface soil, sediments, and surface water
• Inhalation of contaminants in fugitive dust
• Inhalation of vapors while showering
Due to the implementation of the removal actions and institutional and engineering
controls, the only exposure pathways which are still considered viable are ingestion of ground
water and inhalation of vapors during household use of the ground water for the resident.
However, this is contingent upon continued maintenance of the cap, creek bank stabilization, and
institutional controls. These are elements of all of the remedial alternatives except the no action
alternative. Should these elements of the remedy not remain in place, the risks posed by the site
could include all of those identified in the Final Baseline Risk Assessment.
7.1.3 Toxicity Assessment
Benzene is a colorless volatile liquid which is soluble in water. Benzene is classified by
the EPA as a Group A known human carcinogen. This classification is based on several
epidemiological studies which demonstrate an increased incidence of non-lymphocytic leukemia
from occupational exposure.
1,1-Dichloroethene, as called vinylidene chloride or more commonly 1,1-DCE, is a
colorless liquid that evaporates quickly at room temperature. It has a mild, sweet odor and is
flammable. 1,1 -DCE is classified by the EPA as a Group C possible human carcinogen. 1,1-
DCE has toxic effects on the lungs, liver, and kidneys.
1,2-Dichloroethylene, also called 1,2-dichloroethene, 1,2-DCE, acetylene dichloride, or
dichloracetylene occurs as two isomers, cis and trans, with variations in physical properties and
toxicity between the two isomers. 1,2-DCE is commonly used as a general solvent for organic
materials, dye extraction, lacquers, and organic synthesis. The cis-isomer is apparently the more
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common isomer formed as a result of biodegradation. 1,2-DCE has toxic effects by ingestion
and skin contact and may be an irritant and cause narcotic effects in high concentrations,
affecting the respiratory system, skin, eyes, and central nervous system.
Trichloroethylene, also called trichloroethene, TCE, or ethanol trichloride, is a colorless
nonflammable volatile liquid with a chloroform-like odor and is commonly used as a degreasing
agent. TCE in high concentrations can have a narcotic effect and can damage the respiratory
system, heart, liver, and kidneys. TCE is classified by the EPA as a Group B2 probable human
carcinogen.
Vinyl chloride, also called chloroethene, is a colorless gas with a mild, sweet odor. At
this site its presence is probably due to the degradation of other chlorinated solvents. Vinyl
chloride has toxic effects by ingestion and inhalation, affecting the liver, central nervous system,
and peripheral circulation and nerves. Vinyl chloride is classified by the EPA as a Group A
known human carcinogen.
Tables 4.1 and 4.2 from the Final Baseline Risk Assessment, which are attached, list the
toxicity values and potential noncarcinogenic effects and toxicity values and carcinogenic
effects, respectively, for the COCs.
7.1.4 Risk Characterization
For carcinogens, risks are generally expressed as the incremental probability of an
individual's developing cancer over a lifetime as a result of exposure to the carcinogen. Excess
lifetime cancer risk is calculated from the following equation:
Risk=CDI x SF
where: risk = a unitless probability (e.g., 2xlO'5) of an individual's developing cancer
GDI = chronic daily intake averaged over 70 years (mg/kg-day)
SF = slope factor, expressed as (mg/kg-day)"1.
These risks are probabilities that usually are expressed in scientific notation (e.g., 1x10'6).
An excess cancer risk of IxlO"6 indicates that an individual experiencing the reasonable
maximum exposure estimate has a 1 in 1,000,000 chance of developing cancer as a result of site-
related exposure. This is referred to as an "excess lifetime cancer risk" because it would be in
addition to the risks of cancer individuals face from other causes such as smoking or exposure to
too much sun. The chance of an individual's developing cancer from all other causes has been
estimated to be as high as one in three. The EPA's generally acceptable risk range for site-
related exposures is 10'4 to 10'6.
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In the Final Baseline Risk Assessment excess cancer risk was calculated for each of the
three RME scenarios described previously and are as follows:
Excess Cancer Risks for RME Scenarios
RME Cancer Risk
RME Scenario 1 1.38 x lO'6
RME Scenario 2
Childhood (1-6 years) 3.47xlQ-7
Lifetime 5.77 xlO'7
RME Scenario 3
Childhood (1-6 years) 2.18 x 10'2
Lifetime 3,89 x 10'2
RME Scenario 3, the future on site resident, presents an unacceptable level of cancer risk. This
information is presented in greater detail in Tables 5.6 through 5.8 from the Final Baseline Risk
Assessment (attached).
The potential for noncarcinogenic effects is evaluated by comparing an exposure level
over a specified time period (e.g., lifetime) with a reference dose (RfD) derived for a similar
exposure period. An RfD represents a level that an individual may be exposed to that is not
expected to cause any deleterious effect. The ratio of exposure to toxicity is called a hazard
quotient (HQ). An HQ less than one indicates that a receptor's dose of a single contaminant is
less than the RfD, and that toxic noncarcinogenic effects from that chemical are unlikely. The
Hazard Index (HI) is generated by adding the HQs for all COCs that affect the same target organ
(e.g., liver) or that act through the same mechanism of action within a medium or across all
media to which a given individual may reasonably be exposed. An HI less than one indicates
that, based on the sum of all HQs from different contaminants and exposure routes, toxic
noncarcinogenic effects from all contaminants are unlikely. An HI greater than one indicates
that site-related exposures may present a risk to human health.
The HQ is calculated as follows:
Non-cancer HQ = CDI/RfD
where: GDI = chronic daily intake
RfD = reference dose.
GDI and RfD are expressed in the same units and represent the same exposure period (i.e.,
chronic, subchronic, or short-term).
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In the Final Baseline Risk Assessment noncarcinogenic risks were calculated for each of
the three RME scenarios described previously and are as follows:
Noncarcinogenic Risks for RME Scenarios
RME Health Index
RME Scenario 1 0.04
RME Scenario 2
Childhood (1-6 years) 0.29
Lifetime 0.19
RME Scenario 3
Childhood (1 -6 years) 87.3
Lifetime 104
The Health Index for RME Scenario 3, the future on site resident, indicates that site-related
exposures may present a risk to human health. This information is presented in greater detail in
Tables 5.1 through 5.5 from the Final Baseline Risk Assessment.
7.2 Summary of Ecological Risk Assessment
The Final Baseline Risk Assessment also includes a qualitative Ecological Risk
Assessment (ERA). This was prepared prior to implementation of the removal actions and
institutional controls. Although potential ecological risks to site vegetation, the terrestrial food
web, and the aquatic life of Dry Run Creek were identified, the uncertainties of any such risks
were very high due to the qualitative nature of the ERA. However, subsequent to the preparation
of the ERA, the removal actions that took place at the site, particularly capping of the former
disposal area and stabilization of the creek bank, have significantly reduced or eliminated any
threat to site vegetation, the terrestrial food web, or the aquatic life of Dry Run Creek.
8.0 Remediation Objectives
Remedial Action Objectives (RAOs) provide a general description of what the clean up
will accomplish. The RAOs are most often general objectives such as: prevention of exposure to
contaminants; prevention of plume migration; restoration of the ground water to drinking water
quality, etc. These objectives are based on available information and standards such as
applicable or relevant and appropriate requirements (ARARs) of other environmental laws and
risk-based levels established in the risk assessment. The two contaminated media present at this
site include ground water and soil. RAOs are established for each.
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The RAOs for this action are to prevent exposure to ground water containing
contaminants that represent an unacceptable risk to human health or the environment; to contain
the contaminated ground water plume; to restore the ground water to drinking water quality
outside of the disposal area; and to maintain site conditions which prevent exposure to residual
soil contaminants that could pose an unacceptable risk to human health or the environment.
The RAO which is protective of human health for ground water involves the prevention
of ingestion of or direct contact with ground water having a carcinogenic risk in excess of 10"4
and/or a hazard index for noncarcinogens greater than one. The EPA's Maximum Contaminant
Levels (MCLs) from the Safe Drinking Water Act for public water supplies are identified as
ARARs for this site. MCLs represent levels which are considered safe for human consumption.
The ground water cleanup levels for actions involving treatment of ground water are equivalent
to the MCLs which may be associated with the release of VOCs at the site. The MCLs for each
of these VOCs are presented as follows.
EPA's Maximum Contaminant Levels
in
Contaminant MCL
Benzene 5
1,1-Dichloroethene 7
cis-l,2-Dichloroethene 70
Trichloroethene 5
Vinyl chloride 2
Achieving MCLs in the disposal area may not be possible. It is likely that the contaminants are
present in this area as a DNAPL.
The RAO which is protective of human health and the environment for soil involves the
prevention or minimization of direct contact exposures (inhalation, dermal contact, ingestion,
etc.) with soil having a carcinogenic risk in excess of 10"4 or a hazard index for noncarcinogens
greater than one. Specific soil cleanup criteria were not established for this site because the
removal action has eliminated exposure to soil which exceeds the threshold for carcinogenic or
noncarcinogenic risk.
9.0 Description of Alternatives
A feasibility study was conducted to develop and evaluate remedial alternatives for the
site. Remedial alternatives were assembled from applicable remedial process options and were
initially evaluated for effectiveness, implementability, and cost. The alternatives meeting these
criteria were further evaluated and compared to the nine criteria required by the National
Contingency Plan (NCP). In addition to the remedial alternatives, the NCP requires that a no
action alternative be considered. The no action alternative serves primarily as a point of
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comparison for the other alternatives. Four alternatives in addition to the no action alternative
are considered. Alternatives 3, 4, and 5 all involve ground water extraction and treatment but
vary with the emphasis placed on different aquifer units or pumping strategies All of the'
alternatives, with the exception of the no action alternative, include institutional controls
monitoring, and maintenance of the cap and creek bank. An explanation of the common'
elements of the remedial alternatives follows.
_ Each of the alternatives, except the no action alternative, includes maintaining the
institutional controls which are already in place at the Ralston Site. These include-
(1) continued ownership by Rockwell of the fenced-in area, including the disposal area
The area is zoned for agricultural use. The only access to the disposal area is through a locked
gate, thus restricting access by trespassers;
(2) continued listing of the site on the Registry of Hazardous Waste or Hazardous
Substance Disposal Sites pursuant to Iowa Administrative Code 455B.426. According to Iowa
Administrative Code 148.6(5), written approval of the director of the IDNR is required prior to
any substantial change in the use of the listed site. In addition, written approval is also required
to sell, convey, or transfer title of the listed site; and
(3) any new wells in an area specially designated around the site must be approved by
state authorities. A one-mile area surrounding the site has been designated as a protected source
area pursuant to Iowa Administrative Code 567-53.7(4556). According to the promulgated
rule, any new application for a permit to withdraw ground water or to increase an existing
permitted withdrawal of ground water from within the protected water source area will be
restncted or denied, if necessary, to preserve public health and welfare or to minimize movement
ot ground water contaminants from the Ralston site."
All of the alternatives, except the no action alternative, include monitored natural
attenuation of the ground water. Previously in this ROD, in the Section entitled Site
Characteristics, the process of natural attenuation was described as was the fact that data
collected at the site indicates that intrinsic bioremediation of the contaminants of concern is
occurring in the disposal area and areas downgradient in the alluvial, Devonian, and Silurian
aquifers. This information in presented in Appendix A of the Feasibility Study Report The data
from the site also suggests that intrinsic biodegradation will occur at a predictable rate in the
future and degrade TCE and associated breakdown products by fifty percent every one-half to
two years. Also included in this remedial option is the collection of ground water samples from
appropriate monitoring wells and private wells and the analysis of these water samples for VOCs
as well as other constituents to determine the continued effectiveness of the bioremediation
processes.
For each of the alternatives that include ground water extraction and treatment the
process would involve piping the extracted water to the existing treatment building through
underground piping. The water would be treated by air stripping with the off-gas from the air
stnpper being directed through the existing catalytic oxidation unit for destruction of the VOC
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contaminants. Treated water would then be conveyed through underground piping to Dry Run
Creek for discharge.
All of the alternatives, except the no action alternative, include maintenance of the cap
and creek bank. The cap and creek bank would be visually inspected periodically to verify the
integrity and performance of the materials. The cap and creek bank would be regularly
maintained, including mowing, revegetation, and repair, to ensure long-term reliability.
Alternative 1: No action
The NCP requires that the EPA consider a no action alternative against which other
remedial alternatives can be compared. Under this alternative, no further action would be taken
to monitor, control, or remediate the soil or ground water contamination. The existing cap and
bank stabilization would remain in place; however, no inspections or maintenance would take
place to ensure their future effectiveness. Institutional controls have been implemented at the
site, as discussed previously. However, compliance with these institutional controls would not
be ensured under this no action alternative. Natural attenuation of the ground water
contamination is occurring at the site. Under the no action alternative, no monitoring would take
place to determine that these natural attenuation processes continue to be effective in the future
or to determine where the concentration of contaminants has effectively been reduced below
health-based levels. There are no capital or operating costs associated with this alternative.
The expected outcome of this alternative would be that natural attenuation of the ground
water would continue for some period of time but the effectiveness would be undetermined. The
cap and creek bank stabilization could be expected to fail in some locations resulting in the
possibility of direct contact exposure with contaminants, infiltration of precipitation into the
disposal area, and the movement of contaminants into Dry Run Creek.
Alternative 2: Monitored natural attenuation with institutional controls, maintenance of
the cap and creek bank stabilization
With this alternative, the ground water would be allowed to remediate through natural
attenuation processes. Monitoring of the ground water would be done periodically to confirm
that these processes continue to be effective and to determine where the concentration of
contaminants has been reduced below health-based levels outside of the disposal area. The
institutional controls mentioned previously, which have already been implemented, would be
maintained. The cap and creek bank would be inspected periodically to ensure the integrity and
performance of the materials and they would be maintained to ensure long-term reliability. The
estimated annual operation and maintenance costs of this alternative are $32,780 and the
estimated present net worth is $566,800.
The expected outcome of this alternative is that the concentration of contaminants in the
ground water will be reduced below health-based action levels in areas outside of the disposal
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area and there will be no consumption of contaminated ground water in the future. There will be
no direct contact with contaminated soil that remains beneath the cap and no discharge of
contaminated ground water or soil into Dry Run Creek via the stabilized creek bank.
Alternative 3: Monitored natural attenuation with institutional controls, maintenance of
the cap and creek bank stabilization, and Devonian aquifer ground water extraction near
disposal area and treatment
This alternative includes all of the components of Alternative 2 as well as pumping
ground water from wells in the Devonian aquifer near the disposal area. The extracted water
would be treated by air stripping and the off-gas from the air stripper directed through the
catalytic oxidizer in the existing treatment facility. Treated water would then be discharged in
Dry Run Creek under the required permits. The estimated capital cost for implementation of this
alternative is $96,140. The estimated annual operation and maintenance costs are $352,500 and
the estimated present net worth is $6,192,000.
The expected outcome of this alternative is that the contamination in the ground water
will be reduced at about the same rate as Alternative 2. There will be no consumption of
contaminated ground water in the future. There will be no direct contact with contaminated soil
that remains beneath the cap and no discharge of contaminated ground water or soil into Dry Run
Creek via the stabilized creek bank.
Alternative 4: Monitored natural attenuation with institutional controls, maintenance of
the cap and creek bank stabilization, Devonian aquifer ground water extraction near
disposal area and treatment, and Silurian aquifer ground water extraction near disposal
area and treatment
This alternative would include all of the components of Alternative 3 as well as pumping
ground water from the Silurian aquifer near the disposal area. The extracted ground water would
be treated by air stripping and the off-gas from the air stripper directed through the catalytic
oxidizer in the existing treatment facility. Treated water would then be discharged in Dry Run
Creek under the required permits. The estimated capital cost for implementation of this
alternative is $223,600. The estimated annual operation and maintenance costs are $407,700 and
the estimated present net worth is $7,274,000.
The expected outcome of this alternative is that the contamination in the ground water
will be reduced at a rate somewhat more rapidly than Alternative 2. There will be no
consumption of contaminated ground water in the future. There will be no direct contact with
contaminated soil that remains beneath the cap and no discharge of contaminated ground water
or soil into Dry Run Creek via the stabilized creek bank.
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Alternative 5: Monitored natural attenuation with institutional controls, maintenance of
the cap and creek bank stabilization, Devonian aquifer and Silurian aquifer ground water
extraction and treatment over entire area of VOC plume
This alternative would include all of the components of Alternative 4 with the addition of
ground water extraction wells in the Devonian and Silurian aquifers downgradient from the
disposal area so that the entire plume of contaminated water could be captured. The extracted
ground water would be conveyed to the existing treatment building to be treated by air stripping.
The treatment facility would have to be reconfigured and equipped for larger treatment capacity.
Off-gas from the air stripping process would be directed through the existing catalytic oxidizing
unit. Treated water would then be discharged in Dry Run Creek under the required permits. The
estimated capital cost for implementation of this alternative is $801,300. The estimated annual
operation and maintenance costs are $492,800 and the estimated present net worth is $9,324,000.
The expected outcome of this alternative is that the contamination in the ground water
will be reduced at a faster rate than all other alternatives. There will be no consumption of
contaminated ground water in the future. There will be no direct contact with contaminated soil
that remains beneath the cap and no discharge of contaminated ground water or soil into Dry Run
Creek via the stabilized creek bank.
10.0 Summary of Comparative Analysis of Alternatives
Nine criteria are used to evaluate the different remediation alternatives individually and
against each other in order to select a remedy. The nine evaluation criteria are (1) overall
protection of human health and the environment; (2) compliance with applicable, relevant and
appropriate requirements (ARARs); (3) long-term effectiveness and permanence; (4) reduction of
toxicity, mobility, or volume of contaminants through treatment; (5) short-term effectiveness; (6)
implementability; (7) cost; (8) state/support agency acceptance; and (9) community acceptance.
This section of the ROD profiles the relative performance of each alternative against the nine
criteria, noting how it compares to the other options under consideration. The nine evaluation
criteria are discussed below. The "Detailed Analysis of Alternatives" can be found in the FS
Report.
10.1 Overall Protection of Human Health and the Environment
Overall protection of human health and the environment addresses whether each
alternative provides adequate protection of human health and the environment and describes how
risks posed through each exposure pathway are eliminated, reduced, or controlled, through
institutional controls, engineering controls, and/or treatment.
All of the alternatives, except the no action alternative, would provide adequate
protection of human health and the environment by eliminating, reducing or controlling risk by
one or more of the following: through treatment, engineering controls, and institutional controls.
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The designation of a Protected Source Area will prevent unrestricted future use of ground water
within a one mile radius of the site. The ground water monitoring program that is to be
implemented as a part of Alternatives 2 through 5 will ensure that exposure to ground water
contaminants from the site will not occur that would represent an unacceptable human health or
environmental risk because the migration of contamination will be detected. Alternatives 3, 4,
and 5 are more protective than Alternative 2 since these alternatives include ground water
extraction and treatment designed to hydraulically control and capture contaminated ground
water. The effectiveness of any such system cannot be predicted with certainty because the site
area is a complex hydrogeologic setting. Alternative 5 would be the most protective because it
includes downgradient pumping to ensure that contaminants do not migrate beyond the present
area of contamination.
Alternatives 2 through 5 include periodic inspection and maintenance of the cap and
creek bank to ensure that there is no exposure to residual soil contamination in the future. These
alternatives also include the continued listing of the site on the Registry of Hazardous Waste or
Hazardous Substance Disposal Sites pursuant to Iowa Administrative Code 455B.426.
Because the no action alternative is not protective of human health and the environment,
it was eliminated from consideration under the remaining eight criteria.
10.2 Compliance with ARARs
Section 121(d) of CERCLA requires that remedial actions at CERCLA sites at least attain
legally applicable or relevant and appropriate federal and state requirements, standards, criteria,
and limitations which are collectively referred to as "ARARs," unless such ARARs are waived
under CERCLA Section 121(d)4.
Applicable requirements are those substantive environmental protection requirements,
criteria, or limitations promulgated under federal or state law that specifically address hazardous
substances, the remedial action to be implemented at the site, the location of the site, or other
circumstances present at the site. Relevant and appropriate requirements are those substantive
environmental protection requirements, criteria, or limitations promulgated under federal or state
law which, while not applicable to the hazardous materials found at the site, the remedial action
itself, the site location, or other circumstances at the site, nevertheless address problems or
situations sufficiently similar to those encountered at the site that their use is well suited to the
site.
Compliance with ARARs addresses whether a remedy will meet all of the applicable or
relevant and appropriate requirements of other federal and state environmental statutes or
provides a basis for invoking a waiver.
All alternatives, except the no action alternative, would comply with the MCLs
promulgated under the Safe Drinking Water Act for the contaminants of concern in areas found
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not to contain DNAPL. It may not be possible to achieve the MCLs in DNAPL zones. If such
DNAPL zones are located, a technical impracticability waiver under CERCLA will be sought to
waive MCLs as ARARs for these areas.
The Protected Source Area, which has already been implemented in an area surrounding
the site, is an ARAR for Alternatives 2 through 5.
Construction of the ground water extraction system for Alternatives 3 through 5 would
potentially have to comply with requirements of the Clean Water Act and state of Iowa statutes
related to construction in flood plains. Operation of the ground water treatment system would
require compliance with air emission standards. Discharge of treated ground water to surface
water would require permitting in accordance with the National Pollution Discharge Elimination
System requirements and other water quality effluent restrictions.
Alternatives 2 through 5 would meet their respective ARARs from federal and state laws.
Appendix B of the Feasibility Study Report provides a comprehensive listing of all ARARs.
10.3 Long-term Effectiveness and Permanence
Long-term effectiveness and permanence refers to expected residual risk and the ability
of a remedy to maintain reliable protection of human health and the environment over time, once
cleanup levels have been met. This criterion includes the consideration of residual risk and the
adequacy and reliability of controls.
Alternatives 2 through 5 would be effective in the long-term by reducing contaminant
concentrations in ground water. Natural attenuation processes will continue to decrease the
concentrations of contaminants in the aquifers, eventually transforming them to non-toxic by-
products through intrinsic bioremediation. Evidence suggests that natural attenuation processes
have resulted in a steady-state contaminant plume at the Ralston site and have reduced the
contaminant mass loading to the aquifers by reductively dechlorinating VOCs to non-toxic by-
products. This evidence is presented in detail in Appendix A of the Feasibility Study Report.
The monitoring program included in all of the alternatives is needed to document the degree to
which natural attenuation is occurring and to identify whether ground water flow directions,
gradients, or plume boundaries have changed.
Alternatives 3, 4, and 5 include ground water extraction and treatment to further reduce
contaminant residuals. One concern with these alternatives is that the potential impact of ground
water extraction on natural biodegradation processes occurring in the aquifers is not known.
There is evidence to suggest that ground water extraction may have a negative effect on
biodegradation processes. Both the ground water extraction and treatment systems would require
on-going maintenance to prevent operational problems and to continue their effectiveness.
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Alternatives 2 through 5 include periodic inspection and maintenance of the cap and
creek bank to ensure that there is no exposure to residual soil contamination in the future.
The Protected Source Area designation would be an adequate and reliable control for
preventing future withdrawal of, and exposure to, ground water in the future but it does not
prevent current ground water users within the one-mile radius from exposure. The two
residences near the site with private drinking water wells which exhibited detectable levels of
VOCs were connected to a public water supply. These wells are no longer used for drinking
water by the residents. Alternatives 2 through 5 include a ground water monitoring program to
ensure that existing private wells near the site are not impacted by site contamination.
Reviews at least every five years, as required, would be necessary to evaluate the
effectiveness of all of these alternatives because hazardous substances would remain on site in
concentrations above health-based levels.
10.4 Reduction of Toxicity, Mobility, or Volume of Contaminants Through
Treatment
Reduction of toxicity, mobility, or volume through treatment refers to the anticipated
performance of the treatment technologies that may be included as part of a remedy.
Alternatives 2 through 5 include natural attenuation to reduce the toxicity of
contaminants in the aquifers. Intrinsic biodegradation of the contaminants is reducing the
toxicity of site contaminants by completely and irreversibly transforming the chlorinated VOCs
from TCE, DCE, and vinyl chloride to non-toxic by-products through reductive dechlorination
processes. Alternatives 3, 4, and 5 would remove contaminants from ground water by air
stripping and irreversibly destroy the contaminants through the process of catalytic oxidation.
Ground water monitoring would provide information on the movement of contaminants
in ground water but would not directly affect the mobility of the contaminants. Ground water
extraction associated with Alternative 3,4, and 5 would reduce contaminant mobility by creating
a hydraulic barrier around various areas of contamination. Alternative 3 would reduce
contaminant mobility in the Devonian aquifer near the disposal area, Alternative 4 would reduce
mobility in the Devonian and Silurian aquifers near the disposal area, and Alternative 5 would
reduce contaminant mobility throughout the entire plume.
The mass of contaminants present in the aquifers would be reduced by Alternatives 2
through 5. Based on data collected at the site, it is predicted that for every 1,000 pounds of
contaminants entering the aquifers, 500 pounds would be removed during the first six months to
two years by natural attenuation. Another 250 pounds of contaminants would be destroyed
during the next six months to two years and so on, through natural attenuation. Although natural
attenuation is a component of Alternatives 3, 4, and 5, with each additional layer of pumping
added, contaminant removal by naturally occurring processes would become less prominent
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compared to the removal rates attained by pumping. Based on estimated extraction rates for
Alternatives 3,4, and 5, contaminant mass could be removed from the Devonian and Silurian
aquifers at the following rates associated with each alternative:
Alternative Total Extraction Rate Time to Remove 1,000 Ibs.
(Ibs/day) of Contamination (yrs.)
3
4
5
1.4
1.6
1.8
2.0
1.7
1.5
The biodegradation process results in complete transformation of chlorinated VOCs to
non-toxic residuals, primarily ethene and ethane. These residuals are then readily biodegraded to
carbon dioxide and water. Ground water extraction and treatment would remove contaminants
from ground water by air stripping and irreversibly destroy the contaminants through the process
of catalytic oxidation.
Based upon the information presented above, a comparison may be made between the
amount of time it would take to remove an equal amount of the contaminants found in ground
water given the use of natural attenuation alone and the alternatives which include pumping and
treating ground water. Natural attenuation is estimated to remove the contaminants from the
ground water at a rate ranging from about equal to the rate for the least aggressive pump and treat
alternative (Alternative 3) to as long as four times the amount of time needed for the most
aggressive pumping and treating alternative (Alternative 5).
10.5 Short-Term Effectiveness
Short-term effectiveness addresses the period of time needed to implement the remedy
and any adverse impacts that may be posed to workers and the community during construction
and operation of the remedy until cleanup goals are achieved.
In general, the alternatives with the fewest construction activities will pose the lowest risk
to site workers and the community during the remedial action. Therefore, Alternative 2 would
pose the least risk. Since no one is currently exposed to contaminated ground water, only
workers collecting samples from monitoring wells could be exposed to contaminants and this
could be minimized by proper use of personal protective equipment. Cap and bank repair could
result in exposure to contamination by workers, but once again could be minimized by proper use
of health and safety measures and personal protective equipment. Alternatives 3,4, and 5 also
have the possibility of the risks described for Alternative 2, but may have greater risks to workers
posed by well drilling, trenching, and construction.
Maintenance or repair of the creek bank would utilize soil erosion and sediment control
technologies to protect the surface water in Dry Run Creek. Alternatives 3, 4, and 5 would
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involve discharge of treated ground water to Dry Run Creek. This would have to be monitored
to ensure that the discharge does not increase the erosion of the channel at the point of entry.
Construction of piping near Dry Run Creek would have to be completed in a manner that does
not damage the creek.
Air emissions from the ground water treatment processes in Alternatives 3 through 5
would be addressed by engineering controls to ensure that the emissions meet applicable federal
or state air emissions standards, mitigating any adverse on or off site impacts.
10.6 Implementability
Implementability addresses the technical and administrative feasibility of a remedy from
design through construction and operation. Factors such as availability of services and materials,
administrative feasibility, and coordination with other governmental entities are also considered.
Alternatives 2 through 5 are technically implementable. Ground water monitoring and
sampling equipment and procedures are well developed and available. Maintenance of the cap
and bank stabilization would be easily achieved. Ground water extraction and treatment,
included in Alternatives 3 through 5, would be technically feasible to implement. However, the
complex hydrogeologic conditions and high concentrations of contaminants in low permeability
zones could significantly reduce the assumed benefits of ground water extraction. A treatment
system has already been constructed on site, but it would require major modifications to treat the
high water flow rates associated with Alternative 5.
All of the alternatives have few associated administrative difficulties.
10.7 Cost
Cost includes estimated capital and operation and maintenance costs as well as present
worth costs. Present worth cost is the total cost of an alternative over time in terms of today's
dollar value. Cost estimates are expected to be accurate within a range of+50 to -30 percent.
The estimated costs associated with Alternatives 1 through 5 are summarized in Table 2.
The present net worth costs were calculated using an assumed life of 30 years and a three percent
discount rate. Alternatives 2 through 5 all involve the same operation and maintenance costs
associated with maintaining the cap and creek bank stabilization. Alternatives 3 through 5 are
considerably more costly than Alternative 2 because of the significant capital and operation and
maintenance costs associated with the installation and maintenance of a ground water pump and
treat system.
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10.8 State/Support Agency Acceptance
The EDNR has actively participated in the oversight activities for the Ralston site,
including review of the RI and FS Reports. The IDNR has expressed its support for Alternative
2.
10.9 Community Acceptance
During the public comment period, the community expressed its support for the EPA's
preferred alternative. One written comment was received which clarified Rockwell's plans for
future ownership of the property in the vicinity of the disposal area.
11.0 Principal Threat Wastes
The NCP establishes an expectation that the EPA will use treatment to address the
principal threats posed by a site wherever practicable (NCP §300.430(a)(l)(iii)(A)). In general,
principal threat wastes are those source materials considered to be highly toxic or highly mobile
which generally cannot be contained in a reliable manner or would present a significant risk to
human health or the environment should exposure occur.
The contamination remaining in the subsurface soil in the disposal area could be
considered a principal threat waste. The completed removal actions utilized the process of dual
vapor extraction to remove as much of the contamination as possible. The cap that was
constructed over the disposal area eliminates the possibility that exposure to these contaminants
will occur through direct contact and minimizes mobilization of the contamination by reducing
the infiltration of precipitation. All of the alternatives considered for this site, with the exception
of the no action alternation, include the continued maintenance of the disposal area cap.
There is the possibility that contaminants exist in the ground water as DNAPLs, which
may also be considered principal threat wastes. None of the alternatives include actions
specifically designed to address this possible contamination as the locations of areas of DNAPL
have not been identified with any certainty.
12.0 Selected Remedy
The Preferred Alternative for cleaning up the Ralston Site is Alternative 2. Alternative 2
provides for monitored natural attenuation of ground water with institutional controls arid
maintenance of the cap and creek bank stabilization.
As has been discussed in earlier sections of this ROD, data has been gathered and
analyzed which indicates that intrinsic bioremediation of the contaminants of concern is
occurring at this site in the disposal area and in areas downgradient in the alluvial, Devonian, and
Silurian aquifers. This information is presented in Appendix A of the Feasibility Study Report.
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Monitoring of the ground water would be done periodically to confirm that the natural
attenuation processes continue to be effective and to determine where the concentration of
contaminants has been reduced below health-based cleanup levels outside of the disposal area.
The appropriate locations for monitoring the ground water in all three aquifers will be selected
based on ground water monitoring data which continues to be collected at the site and will be
modified as required in the future. Modifications will likely be required as the contaminated
ground water plume changes.
The health-based action levels for the ground water at this site are based upon the MCLs
from the Safe Drinking Water Act for public water supplies, which was identified as an ARAR
for this site. The action levels for each of the chemicals of concern are as follows:
Ground Water Action Levels
in//g/L
Contaminant MCL
Benzene 5
1,1 -Dichloroethene 7
cis-l,2-Dichloroethene 70
Trichloroethene 5
Vinyl chloride 2
Achieving MCLs in the disposal area may not be possible. It is likely that the contaminants are
present in this area as a DNAPL. In the future, if it is determined that MCLs cannot be achieved
in the disposal area, it may be appropriate to consider a technical impracticability waiver. A
technical impracticability waiver may be used when compliance with an ARAR is not feasible
from an engineering standpoint or because of excessive cost, particularly in relation to
performance.
Several institutional controls, which have already been implemented, will be maintained
at the site. Currently, Rockwell owns 27.93 acres, including the former disposal area. The
disposal area is fenced. Rockwell has stated its intention to retain ownership of the property
within the fence, at a minimum. The fence will remain and be maintained to restrict access.
The site will continue to be listed on the Registry of Hazardous Waste or Hazardous
Substance Disposal Sites pursuant to Iowa Administrative Code 455B.426. According to Iowa
Administrative Code 148.6(5), written approval of the director of the IDNR is required prior to
any substantial change in the use of the listed site. In addition, written approval is also required
to sell, convey, or transfer title of the listed site.
A one-mile area surrounding the site has been designated as a protected source area
pursuant to Iowa Administrative Code 567~53.7(455B). Therefore, any new wells in the
designated area must be approved by state authorities. According to the promulgated rule, "any
28
-------
new application for a permit to withdraw ground water or to increase an existing permitted
withdrawal of ground water from within the protected water source area will be restricted or
denied, if necessary, to preserve public health and welfare or to minimize movement of ground
water contaminants from the Ralston site."
The cap and creek bank stabilization, which were implemented during the removal action,
will continue to be inspected periodically and maintained. Specific plans for the inspections and'
maintenance will be developed. They will include the schedule for inspections, plans for
mowing and revegetation, and other items determined necessary to ensure the long-term
reliability of these structures.
Additional ground water sampling will be done to determine whether the elevated levels
of metals found in the disposal area continue to exist and to determine whether they have
migrated beyond the disposal area and pose an unacceptable level of risk to human health. A
plan for the appropriate monitoring wells to be sampled will be developed. The metals which
will be analyzed include all of those which were originally included in the RI. If it is determined
by the EPA that there are concentrations of these analytes which pose an unacceptable level of
risk to human health, it may be necessary to modify this remedial action in the future to address
this risk.
Tables 2 and 3 provide details of a cost estimate for implementation of the preferred
remedy. There are no capital expenditures planned for this remedy. The discount rate used in
calculation of the present net worth costs is three percent. The information in this cost estimate
summary table is based on the best available information regarding the anticipated scope of the
remedial alternative. This is an order-of-magnitude engineering cost estimate that is expected to
be within +50 to -30 percent of the actual project cost.
The expected outcome of this alternative is that the concentration of contaminants in the
ground water will be reduced below health-based action levels in areas outside of the disposal
area and there will be no consumption of contaminated ground water in the future. There will be
no direct contact with contaminated soil that remains beneath the cap and no discharge of
contaminated ground water or soil into Dry Run Creek via the stabilized creek bank.
The Preferred Alternative was selected over other alternatives because it is expected to
achieve substantial reduction of the risks posed by contaminated ground water and maintains the
measures already in place to prevent future exposure to currently contaminated ground water and
soil at a substantially lower cost than the other alternatives. Although the time frame for
reducing the risks may be longer for the preferred alternative, the expected time frame is not
unreasonably long. Therefore, the Preferred Alternative is believed to provide the best balance
of trade-offs among alternatives, with respect to the evaluation criteria.
29
-------
13.0 Statutory Determinations
Under its legal authority, the EPA's primary responsibility at Superfund sites is to ensure
that remedial actions achieve adequate protection of human health and the environment. In
addition, Section 121 of CERCLA establishes several other statutory requirements and
preferences. These specify that when complete, the selected remedial action for this site must
comply with applicable or relevant and appropriate environmental standards established under
federal and state environmental laws, unless a statutory waiver is justified. The selected remedy
also must be cost effective and utilize permanent solutions and alternative treatment technologies
or resource recovery technologies to the maximum extent practicable. Finally, the statute
includes a preference for remedies that employ treatment that permanently and significantly
reduce the volume, toxicity, and mobility of hazardous wastes as their principal element. The
following sections discuss how the selected remedy meets these statutory requirements.
13.1 Protection of Human Health and the Environment
The selected remedy will protect human health and the environment by achieving the
remedial action objectives established for the site. Levels of contaminants in the ground water
will be reduced to levels considered by the EPA to be safe for human consumption. In the short-
term, protection is provided by ground water use restrictions which will prevent exposures to the
contaminated ground water.
13.2 Compliance With ARARs
The selected remedy is expected to comply with ARARs. The MCLs established under
the Safe Drinking Water Act are considered relevant and appropriate for the monitored natural
attenuation component of the remedy for the chemicals of concern. However, if DNAPL zones
are located at the site, a waiver of ARARs may be sought based on the technical impracticability
of achieving MCLs in DNAPL zones. Chapter 133 of the Iowa Administrative Code contains
"action levels" for contaminants in ground water. The IDNR has acknowledged that cleanup
actions have been implemented at the Ralston site that constitute compliance with this state
ARAR.
There are two location-specific ARARs in place at the Ralston site. The site is on the
Registry pursuant to Iowa Administrative Code 567-148(455B). The site cannot be sold,
conveyed, or transferred without written approval of the IDNR. The Protected Source Area
designation pursuant to Iowa Administrative Code 567—53.7(4556) will require the IDNR to
evaluate all proposed new or increased uses of ground water from wells within a one-mile radius
of the Ralston site.
Requirements of the Occupational Safety and Health Act (OSHA) will be complied with;
however, OSHA requirements are not ARARs because OSHA is not an "environmental" law.
30
-------
13.3 Cost Effectiveness
The EPA believes that the selected remedy is cost effective because it will provide overall
effectiveness proportional to its costs. The selected remedy is the least costly of the alternatives
considered for this site.
13.4 Utilization of Permanent Solutions and Alternative Treatment Technology to
the Maximum Extent Practicable
The selected remedy represents the maximum extent to which permanent solutions and
treatment can be utilized in a cost-effective manner at this site. Of the alternatives that are
protective of human health and the environment and comply with ARARs, the EPA has
determined that the selected remedy provides the best balance of trade-offs in terms of long-term
effectiveness, reduction of toxicity, mobility, or volume achieved through treatment, short-term
effectiveness, implementability, and cost. Additional considerations include the statutory
preference for treatment as a principal element as well as state and community aceptance.
All of the alternatives which met the threshold criteria provided long-term effectiveness.
Since the selected remedy does not include treatment, long-term effectiveness is achieved
through monitoring of the ground water. Treatment was found to be impracticable due to
significantly higher costs because it did not provide significantly more protection. Short-term
effectiveness was not a major concern with any of the alternatives considered. While all of the
alternatives which included extraction and treatment of ground water were implementable, it was
not certain to what degree the complex hydrogeologic conditions at the site would negatively
impact implementation of this technology.
13.5 Preference for Treatment as a Principal Element
The selected remedy at this site does not meet the preference for treatment as a principal
element. Treatment was found to be impracticable as it did not provide significantly more
protection for the significantly higher costs. A ground water monitoring program is included to
monitor contaminant levels over time and confirm the adequacy of natural attenuation to reduce
contaminant levels.
13.6 Five-Year Review Requirements
If there are hazardous substances, pollutants, or contaminants remaining at a site above
levels that would allow for unlimited use and unrestricted exposure, pursuant to Section 121(c)
of CERCLA and NCP §300.430(f)(5)(iii)(C), the EPA shall conduct a review of such remedial
action no less often than each five years after the initiation of the remedial action to assure that
human health and the environment are being protected. The Ralston site will require a statutory
five-year review.
31
-------
14.0 Documentation of Significant Changes
The Proposed Plan for the Ralston site was released for public comment in July 1999.
The Proposed Plan identified Alternative 2, monitored natural attenuation, maintenance of cap
and creek bank stabilization, and institutional controls, as the preferred alternative. The EPA
reviewed the written comment submitted during the public comment period. It was determined
that no significant changes to the remedy, as originally identified in the Proposed Plan, were
necessary or appropriate.
32
-------
RESPONSIVENESS SUMMARY
Ralston Site
Cedar Rapids, Iowa
The public comment period on the Preferred Alternative began on July 1, 1999, and
ended on August 2, 1999. A public hearing was held in Cedar Rapids, Iowa, on July 6,1999,
with several members of the public in attendance. No comments were received at this meeting
regarding the Preferred Alternative.
One written comment was received during the public comment period. The written
comment was from Rockwell Collins, Inc. regarding clarification of their plans for property
ownership in the area near the disposal area. The Record of Decision includes the information
provided by Rockwell that they will continue to own the fenced-in area, including the disposal
area.
The written comment is included in the Administrative Record file.
-------
-------
. 1W-6C
-^=^jg
THURNEiS HOTTSE ! PQ-
•r"' c£
' .-*
."^^Jrr-
\f$=>
I fc^i
LEGEND:
• MONITORING WELL
MONTGOMERY WATSON
\\
ROCKWELL INTERNATIONAL
CEDAR RAPIDS, IA
MONITORING WELL LOCATIONS
FIGURE 1
-------
L\mNjARY_TI?ANSJlQRT. SKCONRABY TRANSPORT/ KXPQSUUK
SOURCE EXTflSURJ-:. MKQ1A l«i!JSiiBii_MEULUM ROUTES
RWKPTOR
WASTE
DISPOSAL SITE
| __
E|
SPILLS/LEAKS!
BURNS 1 ^"
SURFACE |
SOILS |~
SUBSURFACE ft
SOILS |
SURFACE I
WATER 1
t
SEDIMENT I
)
GROUNDWATERJ
, Cl ...__. h
1 r-
^ INGESTION •
1 H DERMAL fe
, ^ ABSORBTION | ,
Bfc-
^_
CASUAL |
VISITOR 1
1 ^
ON SITE I
RESIDENTIAL |
_J
OFF -SITE |
RESIDENTIAL |
("DM FEDERAL PROGRAMS CORPORATION
a jtitvsidUrr of Camp Drf^mr k MrKec Inc.
SITE CONCEI'TUAL MODKL
FORMER RALSTON WASTE DISPOSAL SITE
LINN COUNTY, IOWA
Pica IRK 2
-------
TABLE 3.2
FORMER RALSTON DISPOSAL SITE
SURFACE SOIL SAMPLES
DETECTED CHEMICALS STATISTICS
(Results in ug/kg unless otherwise specified)
f >•
1 *• 1 t-
« l J t
CHEMICAL
Anthracene
Arsenic (me/ke)
Barium (ing/kg)
Benzo(a)Anthracene
Benzo(a)Pyrene
Benzo(b)Fluoranthene
Benzo(e.h,i)Perylene
Benzo(k)FIuorantfaene
bis(2-Ethvlhexvl)Phthalate
Butylbenzytohthalate
Cadmium (me/kg)
Chloroform
Chromium (me/kg)
Chrvsene
Copper (me/ke)
Dichloroethene. Cis-1.2-
Fluoranthene
Hexachlorobenzene
Indenof 1 ,2,3-cd)Pvrene
Lead (me/kri
Methvlene Chloride
Naphthalene
Nickel (me/kg)
Phenanthrene
Pyrene
Silver (me/kg)
Tetrachloroethene
Toluene
Trichloroethane. 1.1.1-
rrichloroethene
Xylene (total)
Zinc me/ke)
-4 "? .. . UPPER
FREQUENCY, RANGEOF, ,„„','* 95%
OP ^ E - DETECTED • " '., s* ONE-SIDED
2/3
7/7
7/7
3/3
3/3
3/3
3/3
3/3
2/3
1/3
7/7
1/7
1 7/7 1
3/3
7/7
6/7
1 3/3
1/3
3/3
7/7 • .
1/7
1/3
7/7
3A3
3/3
6/7
6/7
3/7
2/7
6/7
1/7
7/7
42-72
3.2 - 13.1
88.5 - 1570
120 - 360
120 - 360
130 - 470
99 - 360
120 - 360
400 - 1400
86-86
2 - 77.2
6-6
11.2 - 544
140-390
10.3 - 19400
3-110
260-640
65-65
86 - 310
11.3 - 1910
11 - 11
62 - 62
10.9 - 446
130 - 340
230 - 760
0.67 - 202
1 - 94
2 - 8
1 -4
14 - 580
4-4
39.2 - 4130
100
7
435
203
203
247
190
207
717
157
21
9
142
227
4.159
25
390
145
169
557
7
144
135
220
420
52
22
9
8
132
9
75
3
533
136
136
193
148
133
617
62
28
8
201
142
7,230
38
217
69
123
732
2
71
189
108
295
80
34
9
9
206
9
227
10
827
432
432
573
439
431
1.757
261
42
15
289
465
9,468
53
755
262
376
1.095
8
264
273
402
918
111
47
15
15
283
15
«•———..
EXPOSURE
POINT
CONC.
72
96
827
360
360
470
360
360
1 400
86
41 8
289
390
9.468
53
640
310
1.Q9S
g
273
340
760
111
47
g
4
283
4
SRALSSOLXLS 4/11/94
-------
TABLE 33
FORMER RALSTON DISPOSAL SITE
MONITORING WELL SUBSURFACE SOIL SAMPLES
DETECTED CHEMICALS STATISTICS
(Results in ug/kg unless otherwise specified)
CHEMICAL '
Arsenic (mericg)
Barium (mR/kR)
Benzene
Cadmium (mR/kR)
Chromium (mR/kR)
Copper (mR/kR)
Lead (ms/kg)
Mickel (sBfJItg)
Silver (IHR^CR)
TetrachloToetbeoe
Tricbloroetbeoe
Xylene (total)
Zinc (mR/kR)
, .TOTAL FREQUENCE
'SAMPLE: :'-.•, OF '"&§
NUMBER DETECTION
5
5
5
5
5
S
5
S
1
5
5
5
5
5/5
5/5
1/5
5/5
5/5
515
5/5
5/5
1/1
1/5
1/5
1/5
5/5
M If -', '. • ' ' •<•:••••• ", .ifXjri
.,j. ;UETlsCTliD!''.';:*?i:i
CONCENTRATIONS
1.2 - 4.1
32.8 - 187
2-2
1.6-8
5.9 - 36.2
6 -'1,290
7.2 - 467
83 - 67.8
26.2 - 26.2
4-4
6-19
2-6
18.7 - 494
.;...;./;;:..; ;-,.• •• • , .-... UPPER j;
febhfri^.^/ ,-"::; ••:..-' 95% _ EXPOSURE
•Vffl'-J^^t;^- r'-':;:':':: '"•:• ' • ONfe-SlDED1"1' '' POINT
MEAN "STDDEV CONF.LJM. CONC.
2.8
102
4.9
3.5
16
265
100
21
26.2
5.3
8.3
4.9
124
13
68
1.6
25
11.8
573
205
26
4
167
6
6
27
811
296
46
4
167
2
6
27
811
296
46
Statistics not calculated for single sample
0.76
6.0
1.6
207
6
14
6
321
4
14
6
321
-------
TABLE 3.4
FORMER RALSTON DISPOSAL SITE
SOIL BORING SUBSURFACE SOIL SAMPLES
DETECTED CHEMICALS STATISTICS
(METALS, VOCs)
(Results in ug/kg unless otherwise specified)
CHEMICAL
Arsenic (mn/kf.)
Barium (mg/kg)
Chloroform
Chromium (mg/kg)
Copper (me/kg)
Dichloroetbene, Cis-1,2-
Ediylbenzene
Lead (njR/kR)
Nickel (ing/kg)
Silver (mR/kR)
tetracbloroethene
Toluene
Ihchloroethane, 1,1,1-
rrichloroetbenc
Vinyl Chloride
Xylene (total)
Zinc (mg/kg)
"TWTAI
KJLAL,
SAMPLE
NUMBER
5
5
5
8
5
5
8
8
5
r~ s
5
8
8
8
8
8
8
5
FREQUENCY
OF
DETECTION
1/8
5/5
, 5/5
5/5
1/8
5/5
5/5
5/8
1/8
5/5
5/5
3/5
5/8
678
1/8
8/8
1/8
3/8
5/5
• ;..:;.;'::;;•/*•
RANGEOF;:; :.
DETECTED/. '
CONCENTRATIONS
11-14
2.8 - 9.1
106 - 1,160
4-300
1 1 - 720.000
16.1 - 474
8.8 - 15.400
2 - 20.000
11 - 5,700
8.2 - 3,000
14.1 - 937
0.68 - 250
2 - 1.800.000
1 - 6,300,000
2 - 2
3 - 17.000.000
11-660
11 - 700.000
38.1 - 4.650
194.023
4
330
64
90,272
112
3.221!
196,878
194.560
629
202
51
225,621
792,378
194,022
2,125,652
194,011
90,407
1,071
547,898
3
464
132
254,449
203
6,810
546,788
547.684
1.326
411
111
636.147
2,225,448
547,898
6,010.145
547,903
246,444
UPPER
95%
ONE-SIDED
561.106
7.0
772.7
189.7
260,749
304.8
9.718.6
563,217
561,499
1,893.2
593.6
157.0
651,829
2,283.392
561.105
6,152,350
561,097
255,521
EXPOSURE
POINT
14
7.0
773
190
260.749
305
9.719
20.000
5.700
1,893
594
157
651,829
2,283,392
6,152.350
660
ISRALSBSSJCLWTTABLEZ
-------
TABLE 3.5
FORMER RALSTON DISPOSAL SITE
SOIL BORING SUBSURFACE SOIL SAMPLES
DETECTED CHEMICALS STATISTICS
(SEMI-VOLAT1LES, PCBs. PESTICIDES)
(Results in ug/kg unless otherwise specified)
' CHEMICAL : -''•'
alpha-Chlordane
Aroclor-1260 (rag/kg)
Ben20fa)Anthracene
Benzo(a)Pyrcne
BenzoftOFIuoranthene
Benzo(R.hj)Pery]ene
BenzoflOFluoranthene
bis(2-Ethylhexyl)Phthalate
Butylphthalate, Di-n-
Chryeene
ODD. 4.4'-
DDE.4,41-
DDT.4,41-
Endrin aldehyde
Buonnthene
pamma-Chlordaoe
Hepuchlor
Hepuchlor epoxide
Hexachlorobenzene
Indem>n.2,3-cd)Pyrene
Phenanthrene
Pvrene
r/5' • *
: TOTAL
•'•'SAMPLE''
NUMBER
3
3
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
• I "
FREQUENCY
OF -
'DETECTION
1/3
1/3
1/2
2/3
' 2/3
1/3'
2/3
2/3
3/3
3/3
1/3
2/3
IK
1/3
2/3
1/3
1/3
1/3
1/3
2/3
1/3
2/3
. ' t ,
, RANGEOF
1 '
DETECTED
CONCENTRATIONS
9.6 - 82
190 - 4,200
62-62
100 - 120
110 - 130
130 - 130
64-87
370 - 650
85 - 140
58 - 120
19 - 340
19 - 110
14-400
19-140
82 - 150
9.6 - 78
3.8 - 3.8
9.6 - 10
90-90
88-100
60-60
110 - 240
t.
•t
^ i
" MEAN
62
1,495
124
135
142
168
112
408
118
93
180
62
201
56
139
61
36
38
155
124
145
178
STDDEV
51
2,343
87
44
39
33
64
233
29
32
165
50
193
73
52
50
55
54
56
53
74
65
UPPER
95%
ONE-SIDED
CONF.LIM.
148
5,445
512
210
207
224
220
801
168
146
459
147
527
179
227
145
129
129
250
213
269
288
EXPOSURE
POINT
CONC.
82
4.200
62
120
130
130
87
650
140
120
340
110
400
140
150
78
3.8
10
90
100
60
240
(S8AttBSS.XlW)7ABtE3 10/14/94
-------
TABLE 3.6
FORMER RALSTON DISPOSAL SITE
MONITORING WELL GROUNDWATER SAMPLES
DETECTED CHEMICALS STATISTICS
(Results in ug/L)
r& ^^S-'-fS w •• V*> >J '<£?:*'• ij
Stfc* :^'f '%' *'$.'
.",[\ "'* """-\ , ;; I"' *\
' '" CUBICAL
Aluminum
Antimony
Arsenic
Barium
Benzene
Beryllium
Bromodichloromethane
Butylphthalate, Di-n-
Cadmium
Calcium
Chloroform
Chromium
Cobalt
Copper
Dichloroethanc, 1,1-
Dkhloroethene, 1,1-
Dichloroethene, Cis-1 2-
Dichloroethene, Trans- 1,2-
Bthyibenzene
iron
Lead
Magnesium
Manganese
Methylene Chloride
Nickel
Potassium
Selenium
Silver
Sodium
Tetrachloroethene
Toluene
Trichloroethene
Vanadium
Vinyl Chloride
Xylene (total)
Zinc
V * £ ^ ff
[•. •- •" f'r^''<&&?.
jSftMrfag'
KUMBbH
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7 .
7
7
7
7
7
7
7
7
7
7
7
7
7
**#* Jibuti
Dii'iiiu'lKi&J,
7/7
4/7 •
5/7
7/7
' 3/7
3/7
1/7
1/7
2/7
7/7
1/7
5/7
6/7
6/7
2/7
6/7.
6/7
6/7
2/7
7/7
6/7
7/7
7/7
7/7
6/7
7/7
2/7
1/7
7/7
5/7
2/7
6/7
3/7
5/7
2/7
7/7
^s*^!^^^^?!'?
%., % * JA^">''
%,. ^ ,f " ;
21,100
94.5
12
304
27
2.5
6
2
4.3
661.000
500
31
68.2
155
12
270
18,000
32
0.6
39,400
68.6
179,000
1,910
10
40.4
6,900
4.8
4.9
23,600
14
7
5,200
51
2,100
3
253
SRALMWCW.XLS 3/VSM
-------
TABLE 3.7
FORMER RALSTON DISPOSAL SITE
SOIL BORING GROUNDWATER SAMPLES
DETECTED CHEMICALS STATISTICS
(Results in ug/L)
" =•'.. ~' &'•:•*' £'$':?l"'.
CHEMICAL'"'*' '
Acetooe
Benzene
Butanooe. 2-
ButylphthalMe, Di-D-
Carbon Bisulfide
^bloroforiu
Dicblorobenzene, 1,2-
DicbloToethaoe, 1,1-
Dicbloroetbece, 1,1-
Dichloroetbene, Cis-1,2-
DicbloToethe&e. Trans-1,2-
Dictdoropropane, 1,2-
Diethylphtbalate
Dimethylpbeno], 2,4-
Etbylbenzene
Isopborone
Methylene Chloride
Metbylnapbtbalene, 2-
Methylpbenol. 2-
MethvlpbcDol. 4-
Napbtbaleoe
Nitropbenol, 2-
NitropbcDol, 4-
Pentanone. 4-Metbyl-2-
'faenol
Tetrachloioethene
Toluene
Tricblorobenzene, 1,2.4-
Triehloroetbane, 1,1,2-
Trichloroelbene
Vinyl Chloride
Xylene (total)
• U"
'.TOTAL:
SAMPLE,
NUMBER
8
8
8
3
8
8
3
8
8
8
8
8
3
3
8
3
8
3
3
3
3
3
3
8
3
8
8
3
8
8
8
8
J f H-'r^ - ~" <- ~ - UPPER
FREQUENCY, RANGEOF^^^ ;" , , 95% EXPOSURJE
OF ,.-» DETECTED *<•,,' *. ONE-SIDED POINT
DETECTION CONCENTRATIONS MEAN STDDEV CONF.LIM^ CONC
4/8
IK
1/8
1/3
1/8
1/8
3/3
1/8
5/8
7/8
5/8
1/8
1/3
2/3
3/8
1/3
1/8
1/3
3/3
3/3
1/3
1/3
1/3
2/8
3/3
4/8
5/8
1/3
2/8
7/8
5/8
3/8
2 - 200.000
2-170
2 - 360,000
1 - 1
0.6 - 0.6
2 -5300
2 - 150
0.2 - 0.2
1 -480
0.9 - 230,000
2 -400
0.4 - 0.4
1 - 1
2 - 14
0.9 - 730
7 -7
2 - 16,000
4 -5
5 -260
10 -300
4-4
11 -20
12 - 18
2 - 2.100
4 -.170
0.4 - 3.000
0.6 - 39.000
1 1 - 45
0.5 - 1.100
2 - 1.000.000
2 - 29.000
0.3 - 3.000
26.601
1.335
46313
19
1376
1,976
53
1376
1.348
68,930
1,348
1376
19
7
1358
21
3313
20
99
115
20
25
56
1,529
88
1.681
9.626
34
1,451
135,518
6,193
1,688
70,150
3.506
126,796
27
3.492
3.725
84
3.492
3.501
97,753
3,500
3,492
27
6
3,501
25
6.193
26
140
160
26
23
64
3.499
83
3.517
14.889
24
3,477
350,236
10.496
3^14
73.600
3.683
131.265
64
3,715
4,471
195
3.715
3.693
134,423
3.693
3,715
64
18
3,704
63
7.462
64
335
386
64
63
164
3.874
228
4.037
19,601
75
3.780
370,170
13,225
4,043
200.000
170
360,000
1
1
5300
150
0
480
230,000
400
0
1
14
730
7
16.000
5
260
300
4
20
18
2.100
170
3.000
39.000
45
1,100
1,000,000
29.000
3,000
S8MS8GWXS 10/14/M
-------
TABLE 3.8
FORMER RALSTON DISPOSAL SITE
RESIDENCE WELLS GROUNDWATER SAMPLES
DETECTED COMPOUNDS STATISTICS
(Results in ug/L)
CHEMICAL
Barium
Butylpbtbalate. Di-n-
Cbromium
Copper
Dichloroetbeoe. Cis-J.2-
Lead
Metbylene Chloride
Nickel
retrachloroetbene
rrichloroctbane. 1.1.1-
rrichloroctbene
Zinc
TOTAL
SAMPLE
NUMBER
7
7
7
7
7
7
7
7
7
7
7
7
UPPER
FREQUENCY RANGE OF 95* EXPOSURE
°F DETECTED ONE-SIDED POINT
DETECTION CONCENTRATIONS MEAN STDDEV CONF.L1M. CONC
7/7
1/7
1/7
7/7
1/7
5/7
1/7
1/7
1/7
2/7
2/7
7/7
2 -4
67.1 - 182
2 -2
3 -3
7.4 - 55
2 -2
2 - 5.4
0.2 - 0.2
6 - 6.2
0.8 - 0.8
0.2 - 0.2
1-6
21.4 - 213
1.7
123
4.6
2.0
19
1.1
3.0
0.89
3.5
0.97
0.77
1.7
79
1.1
38
1.1
0.65
17
0.38
1.7
0.30
1.2
0.076
0.39
1.9
67
2.5
151
5.4
2.5
31
1.4
4.2
1.1
4.3
1.0
1.1
3.1
128
4
182
•>
3
55
-i
5.4
0.2
6.2
0.8
0.2
6
SRALRESW.XLS 3/18/93
-------
TABLE 3.9
FORMER RALSTON DISPOSAL SITE
DRY RUN CREEK SURFACE SEDIMENT
DETECTED CHEMICALS STATISTICS
(Results in ug/kg unless otherwise specified)
CHEMICAL
Acetone
Anthracene
Arsenic (me/ke)
Barium (me/kc)
Benzo(a)Anthiacene
Ben2o{a)Pyrene
Benzo(b)Fluoranthene
Benzo(k)Fluoranthene
Cadmium (mg/ke)
Chromium (me/ke)
Chrvsene
Copper (me/kit)
Dichloroethene. Cis-1.2-
Ruoranthene
Indcnod .2.3-cd)Pvrcne
Lead (me/ke)
Nickel (me/ke)
Phenanthrene
Pyrene
Trichloroethene
Zinc (me/ke)
UPPER
TOTAL FREQUENCE RANGE OF 95% EXPOSURE
SAMPLE OF DETECTED ONE-SIDED POINT
NUMBER DETECTION CONCENTRATIONS MEAN STDDEV CONF.LIM. CONC.
4
4
4
4
3
4
4
4
4
4
3
4
4
4
4
4
4
4
4
4
4
1/4
1/4
4/4
4/4
1/3
2/4
3/4
, 2/4
4/4
4/4
213
4/4
2/4
3/4
1/4
4/4
4/4
3/4 •
3/4
1/4
4/4
11 -23
40-40
I.I - 1.5
18-78
140 - 140
69 - 120
40 - 140
57-84
1.4 -2
3.2 - 5.3
37 - 130
2-5.1
4 - 14
77 - 340
44-44
3.7 - 17
3.2 - S.I
38 - 160
66 - 320
2-2
14.4 - 20.9
10
156
1.4
46
177.
145
124
133
1.7
4.2
127
3.0
7.4
206
157
8.3
4.5
128
198
5.0
17
8.6
79
0.17
28
38
64
73
75
0.30
1.1
89
1.4
4.5
108
77
6.1
0.89
76
104
2.0
2.8
20
249
1.6
79
240
220
210
220
2.0
5.5
277
4.7
13
332
248
IS
5.6
218
321
7.4
20
20
40
1.5
78
140
120
140
84
2
5.3
130
4.7
13
332
44
15
S.t
160
320
2
20
SRAlS3D.XtS 3/18/93
-------
TABLE 3.io
FORMER RALSTON DISPOSAL SITE
SURFACE WATER
DETECTED CHEMICALS STATISTICS
(Results in ug/L)
CHEMICAL
Barium
Carbon Disulfide
Copper
Dicbloroetbene. 1.1-
Dichloroetbene. Cis- 1 .2-
Dichloroetbenc. Trans- 1.2-
Lead
Nickel
retracbloroetbene
Toluene
Trichloroetbane. 1.1.1-
TrichloroetheDe
Vinyl Chloride
Xylene (total)
Zinc
TOTAL FREQUENCY
SAMPLE OF
NUMBER DETECTION
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7/7
2/7
1/7
6/7
1/7
6/7
1/7
7/7
2/7
2/7
1/7
1/7
4/7
5/7
1/7
7/7
UPPER
RANGE OF 95% EXPOSURE
DETECTED ONE-SIDED POINT
CONCENTRATIONS MEAN STDDEV CONF.LIM CONC
35.4 - 195
3 -8
0.4, - 0.4
3 - 16.1
0.4 - 0.4
0.3 - 92
0.9 - 0.9
2.4 - 12.8
6 - 8.1
0.4 - 0.7
0.9 - 0.9
0.3 - 0.3
1-7
2-20
0.3 - 0.3
26.1 - 64.2
5.6
95
2.7
0.91
11
0.91
23
1.0
7.2
4.3
0.87
1.0
0.90
2.0
5.9
0.90
42
3.2
64
2.4
0.23
4.7
0.23
32
0.038
3.4
1 1
0.24
0.038
0.26
2.2
6.7
0.26
12 •
7.9
141
4.4
l.i
15
1.1
47
1.0
9.7
5.9
1.0
1.0
1.1
3.6
11
1.1
79
141
4.4
0.4
15
0.4
47
0.9
9.7
5.9
0.7
0.9
0.3
3.6
11
0.3
IALSURHXLS 3/18/93
-------
TABLE 41
TOXICITY VALUES
POTENTIAL NONCARCINOGENIC EFFECTS
CHEMICAL
CHRONIC
R/D
SUB CHRONIC
RfD*
CONFIDENCE CRITICAL EFFECTS
LRVEl.
RfDSOURCE/ ,. UNCERTAINTY/ dile
RfD BASIS MODIFTTNO FACTORS online
Oral Roote - fm«/k«>da»l • ...
acetone
aluminium
ailhracene
antimony
arsenic
btrium
benzfatanthracene
benzene
benzofalorrene
benzoflrtfluorantfiene
beozo(«.h,rtDeryleiie
benzoflOfluoramhene
Krvllium
bis(2-ethylnexyl)phlhalale
brornodichloromethaDe
buunone. 2-
butyl benzylphthalate
butylphlhalate, di-n-
cadmtamfinfoodl.
cadmium (ia water}
I.OOE-01
I.OOE+00
low
data inadequate for quinlililivc risk assessment
3.00E-01
4.00E-04
3.00E-M
7.00E-02
no data
pendins
no data
no data
no data
no data
S.OOE-03
2.00E-02
2.00E-02
6.00E-OI
2.00E-OI
I.OOE-01
l.OOE-03
5.00E-04
3.00E+00
4.00E-04
3.00&04
7.00E-02
5.00E-03
2.00E-02
2.00E-01
5.00E-01
2.00E+00
I.OOE+00
low
low
medium
medium
low
medium
medium
low
low
low
high •
increased liver/ kidney weight
NOEL
longevity, blood glucose
hyperpitmentation. etc.
NOAEL
NOAEL
increased liver weight
renal cvtomeiialv
decreased fetal birth wetarit
increased liver weight
increased mortality
proteinuria
gavige/IRIS
/HEAST
gavage/lRIS
oral/IRIS
epidemiology/I R1S
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
food/IRIS
tavage/XRIS
water/IRIS
food/IRIS
food/IRIS
/IRIS
epidemiology/IRIS
1000
3000
1000
3
3
100
1000
1000
3000
1000
• 1000
10
10
12/1/90
7/1/91
2/1/91
10/1/91
9/1/90
5/1/91
3/1/91
5/1/93
8/1/91
8/1/90
10/1/89
calcium
carbon disutfide
Chlordane, alpha
I.OOE-01
6.00E-05
l.OOE-01
6.00E-05
medium
low
fetal (oxicityAnatformations
liver hypertrophy
inhalation/IRIS
food/miS
100
1000
9/1/90
7/1/89
Chtordane, samma .
chloroform
chromiumfvn
chrysene
l.OOE-02
5.00E-03
l.OOE-02
2.00E-02
medium
low
fatty cysts-liver
NOAEL
dau inadeouate for quantitative risk assessment
oral capsule/IRIS
water/IRIS
/HEAST
1000
500
7/1/92
. 3/1/88
31192
cobalt
copper
ODD
)DE
)DT
lichforohenzene, 1,2-
lichtoroethane.l.l-
dichloroethene, 1,1-
dichloroefhene. cis-1,2-
djchloroclhene, trans-1,2-
dichloropropane, 1,2-
diethvlphlhalate
dimelhytphenol, 2,4-
data inadequate for quantitative risk assessment
no data
no data
5.00E-04
9.00E-02
I.OOE-01
9.00E-03
l.OOE-02
2.00E-02
no data
8.00E-0!
2.00E-02
5.00E.04
9.00E-OI
l.OOE+00
9.00E-03
I.OOE-01
2.00E-OI
8.00E+00
2.00E-OI
medium
low
medium
low
low
low
liver lesions
NOAEL
NOAEL
liver lesions
decreased hematocril, etc.
increase serum alk. phosphatase
decreased growth rate
lethargy.prostnlian, etc.
/HEAST
/IRIS
/IRIS
food/IRIS
gavacte/IRIS
inhalalion/HEAST
water/IRIS
eavaee/HEAST
/IRIS
/IRIS
food/IRIS
Ravage/lRIS
100
1000
1000
1000
3000
1000
1000
3000
31/92
9/30/87
3/1/91
3//92
4/1/89
3//92
1/1/89
8/1/91
1 1/1/90
endrin aldehyde
RALNON.XLS 10/14/94
-------
TABLE 4.1
TOXICITY VALUES
POTENTIAL NONCARCINOGENtc EFFECTS
CHEMICAL
ethyl benzene
fluonnthcne
indenofl,2,3-c.d}pyrene
isophorone
lead
magnesium
manganese
CHRONIC
RID
l.OOE-01
4.00E-02
5.00E-04
1.30E-05
8.00E-04
no did
SUBCHRONIC
ROJ«
I.OOE+00
4.00E-OI
5.00E-04
1.30E-05
8.00&04
CONFIDENCE
•LEVEL
•• low
low
law
low
medium
CRITICAL EFFECTS
liver/kidney toxieitv
liver weights, etc.
NOEL
increased liver weight
daU i nadequate for qtnntiulive risk assessment
2.00E-01
2.00E4-00
low
NOEL
(USE INTEGRATED UPTAKE/BIOKINETIC MODH,)
l.OOE-01
methvlene chloride (dichlorom 6.00E-02
melhylnaphlhalene, 2-
nethylphenol, 2-
melhvlphenol. 4- fD-cresoD
naphthalene '
nickel
niirophenol. o- fnitrochenol.
nitrophenol, p- (nitrophenol.
PCBs
xmtanone, 4-methyl 2-
phenanthrene
ihenol
potusium
pyrene
selenium-
silver
5.00E-02
5.00Efl2
withdrawn
2.00E-02
l.OOE-01
6.00E-02
5.00E-OI
5.00E-OI
2.00E-02
medium
medium
medium
medium
2- data inadeouate for auantiutive risk assessment
4- pending
no data
5.00E-02
.
i.OOE-01
data inadequate for quantitative risk assessment
6.00E-OI
3.00E-02
5.00E-03
5.00E-03
6.00E-01
3.00E-01
3.00E-03
5.00E-03
low
low
hiuh
low
CNS effects
liver toxichy
decreased weight gain
decreased body weight
liver and kidney effects
tow fetal body weight
decreased kidney weights
ttlenosis
argyna
RfD SOURCE/ . -UNCERTAINTY/ date
1 RID BASIS MODIFYING FACTORS online
/IRIS
food/IRIS
food/IRIS
/IRIS
/HEAST
-
waterflRIS
Bavane/HEAST
foodHRIS
/HEAST
/IRIS
/IRIS
/HEAST
/HEAST
gavage/IRIS
gavage/IRIS
epidemioloRV/IRIS
epidemioloRy/IRIS
1000
3000
300
1000
100
1000
1
100
1000
1000
300
1000
100
3000
3
3
6/1/91
7/1/91
3/1/91
3/1/91
4/1/91
3OT2
1/1/9!
8/1/90
3/1/88
3//S2
3/1/93
1/1/92
3//92
3//92
2/1/90
7/1/91
9/1/91
12/1/91
sodium
tetrachloroethene
toluene
trichlorobenzene. 1.2,4-
irichloroethine. I.I.I-
trichtoroetlume, 1.1.2-
trichtoroelhene
vanadium (pentoxide)
I.OOE-02
2.00E-OI
I.OOE-02
9.00E-02
4.00E-03
6.00E-03
9.00E-03
l.OOE-01
2.00E+00
I.OOE-02
9.0CE-01
4.00E-02
9.00E-03
medium
medium
medium
medium
low
hemtotoxicitv
liver and kidney weights
increased adrenal weight!
liver toxieitv
liver effects
decreased hair cystine
cavage/IRIS
givage/IRIS
water/IRIS
orat/HEAST
waler/IRIS
/ECAO
food/IRIS
1000
1000
1000
1000
1000
100
3/1/88
8/1/90
5/1/92
31192
8/1/90
6/30/88
vinyl chloride
xylenes
zinc
2.00E+00
3.00E-OI
4.00E+00
medium
medium
hvceractivity. etc.
blood anemia
gavace/lRIS
/IRIS
too
3
9/30/87
3/1/94
RALNON.XLS 10/14/94
-------
TABLE 4.1
TOXICtTY VALUES
POTENTIAL NONCARCIMX5ENIC EFFECTS
• CHEMICAL
lahalau'o* Rome
acetone
ilumjnium
anthracene
antimony
arsenic
barium
benzdHnthncene
benzene
benzofalpyrene
beniofblfluoranthene
benzofc.hjtoervlene
benzoflOfluoranlhene
beryllium
bi5(2-ethylh«xvl)i>hthalate
broraodidtlcromethine
bulanone, 2-
jutvl benzylphthalate
bntvlphlhalite, di-n-
cadmium
cidmium
CHRONIC SUBCHRONIC CONRDENCE CRITICAL EFFECTS
RfD RfD» IRVEL . • • .
(mK/m3)
nodtta
data imdequtle for risk aue«ment
no data
no data
no data
5.00E-04 . 5.00E-03 fetocoxicily
no data
pending
no data
no data
no data
no data
no data
no data
nodau
. l.OOE+00 low decreased fetal With weixhl
no data
data inadequate for verification of inhalatation RfC
pending
no data
RfD SOURCE/ ' UNCERTAINTY/
RfD BASIS MODIFYrNOPACTORS
/IRIS
/HEAST
/IRIS
/IRIS
/IRIS
inhalation/HEAST 1000
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
inhiUtion/IRIS • 3000
/IRIS
/IRIS
/IRIS
date
online.
31192
3/1/93
7/1/92
10/1/90
calcium
carbon disulfide
Chlordane, alpha
I.OOE-02 l.OOE-02 fetus toxicity
pending
/HEAST 1000
/IRIS
31/92
Chlordane, gamma
chloroform
DDD
DDE
DDT
dichloroethene. cis-1,2-
dichloropropane. 1,2-
diethylphlhalate
dimeihylphenol. 2.4-
pending
pending
no data
no data
no data
no data
no data
2.00E-OI 2.00E+00 decreased weight gain
I.OOE-01 l.OOE+00 NOEL
no data
no data
4.00E-03 I.30E-02 medium hypcrplisia of the nasal mucosa
no data
no data
/IRIS
/IRIS
/HEAST
/IRIS
/IRIS
/IRIS
/IRIS
inhalation/HEAST 1000
inhalalioa/HEAST 1000
/IRIS
/IRIS
/IRIS
iniulaUon/IRIS 300
/IRIS
/IRIS
3/192
3/1/93
3/1/93
1 2/1/91
endrin aldehyde
RALNON.XLSIO/M/94
-------
TADLE4.1
TOXIC1TY VALUES
POTENTIAL NONCARCINOGENIC EFFECTS
• CHEMICAL
ead
CHRONIC SUBCHRON1C CONFIDENCE CRITICAL EFFECTS
WD RfD* LEVEL '
nodsta
RfD SOURCE/ : UNCERTAINTY/
inhalation/lRIS 300
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/HEAST
/IRIS
date
3/1/93
3/1/91
4.00E-04 4.00E-04 medium increased respiratory symptoms
data inadequate for derivation of inhalttation RfC
data inadequate for derivation of inhalalation RfC
nodata
pending
/HEAST 100
/IRIS
/IRIS
/IRIS
/IRIS
12/6/90
3//92
nilrophenol, o- (nilrophenol, 2- data inadequate for quanliutive risk assessment
niirophenol, p- (nitrophenol, 4- data inadequate for derivation of inhalation RfC
PCBs
Kntanone. 4-melhvl. 2-
)heninthrene
ihenol
no data
g.OOE-02 8.00E-01 inaeased liver weight
no data
data inadequate for derivalioR of inhalation RfC
/IRIS
/IRIS
/HEAST 1000
/HEAST
/IRIS
1 0/1/9 1
31/92
3//92
3/1/91
xjtassium
ivrene
selenium
silver
no data
nodata
nodata
/IRIS
/IRIS
/IRIS
odium
letrachlofoethene
toluene
•ichlorobenzene. 1.2.4-
trichloroethane, 1,1,1-
Itichloroelhane, 1.1,2-
trichloroethene
vanadium (pentoxide)
no data
4.00E-OI 2.00E+00 medium CNS effects
9.00E-03 9.00E-02 liver oorphvria
I.OOE+00 I.OOE+OI liver toxicity
pending
pending
no data
/IRIS
/HEAST 300
inhalilion/HEAST 1000
oral/HEAST 1000
/IRIS
/IRIS
/IRIS
3//92
3/1/93
3/1/92
vinyl chloride
xylerua (mixture)
zinc
pending
nodata
/IRIS
/IRIS
RALNON.XLS 10/14/94
-------
TABLE 4J
TOX3CITY VALUES
POTENTIAL CARCINOGENIC EFFECTS
CHEMICAL
Slope , , Drinking Water Weight of Evidence Type of SF Basis/
Factor Unit Risk ' Classification CiDcerW SFSource
date
online
VB! RoDte • ' fmRflcfi-divV) ' fuR/Li)
acttoae
no data
D
/IRIS
12/1/90
aluminium
acthraceee
antimoey
arseaic (calculated from unit risk)
barium
beoxfa)acthr*cene (BaP equivalent)
beszeoe
be DzoCatayrene
beazo(b)flttQractheo£ (BaP equivalent)
»eazo(t Ji.i)pcTvl CDC
beezoOOflDCrantheDe <3aP equivalent)
beryllium
bij{2«ethvlhexy"i)piTfthalaie
bfomodichlofo methane
butyl beazylphthalaie
btttvfc&lhaUle. di-n-
cadmiam
inadequate dala
DO data
1.75E+00 5.00E-05
no data
7.30E-01
2.90E-02 8.30E-07
7.30E+00 2.IOE-04
7.3D&4)!
i Did ecru lie data
7.3DE-02
4.30E+00 l^OE-04
MD&Q2 4.00E-07
1.30&0! 3.70E-06
no data
D
A
B2
A
B2
B2
D
B2
B2
B2
B2
C
D
Bl
/IRIS
/IRIS
lung/skin water: inhalation/EPA
/IRIS
/IRIS
leukemia enidemioloev/IRIS
food/gavage. etc,/IRIS
/IRIS
/IRIS
/IRIS
inhalaiion/IRIS
food/1 RJS
eavace/IRIS
/IRIS
/IRIS
/IRIS
1/1/91
1988
12/1/90
4/1/92
7/1/92
12/1/90
12/1/90
11/1/90
1/1/91
8/1/91
7/1/92
8/1/91
8/1/91
6/1/92
caleinm
carbon diiulfide
Qilordaae. alpha
no dala
130E+00 3.70E-05
B2
/IRIS
/IRIS
1/1/91
Oikrdaae. Tttnma
chloroform
chromiumfVn
chryscoe (BaP equivalent)
6.IO&O3 1.70E-07
7.3OE-03
B2
A
B2
gavage/IRIS
lung' epidemioloev/IRIS
/IRIS
3/1 »1
3/1/91
12/1/90
cobalt
copper
ODD
DDE
DDT
dkhlorobeBiene, 1.2-
djchloroeihiae. 1,1-
djcWoroelhene, 1.1-
dlchloroethene. cii-1 ,2-
dJcHoreetheoe, UBBS-! Jl~
dlchlorofropane. 1,2-
dlethylphthalaie
dimcthylpheaoU 2.4-
'inadequate data
2.40E-01 6.90&06
3.40E-01 9.70E-06
3.40&01 9.70E-06
inadequate data
inadequate data
6.00E-01 I.70E-05
no data
nodau
6.80E-02 1.90E-06
inadequate dala
no data
D
B2
B2
B2
D
C
C
P
B2
D
/IRIS
Fbod/IRlS
food/lRIS
food/lRIS
/IRIS
/IRIS
inhalalion/IRIS
/IRIS
/IRIS
savage/HEAST
/IRIS
/IRIS
8/1/91
8/22/88
8/22/88
5/1/91
1/I/9I
10/1/90
2/1/91
12/1/90
3//92
8/1/91
eodria aldehyde
ethyl beftie&e
fluoraDtheBe
Srplachlor
Keptachlor epoxtde
)DdeiK)(lX3>c.d)pyrtne (BaP equivalent*
no data
inadequate data
4.50E400 130E-04
9.10E+00 2.60E-04
I.60E+00 4.60E-05
7.30E-OI
D
D
B2
B2
B2
B2
/IRIS
/IRIS
/IRIS
food/I RJS
/IRIS
/IRIS
8/1/91
12/1/90
1/1/91
4/1/92
4/1/92
12/1/90
ITOD
tsophorooe
lead
mipMiIum
rrunfaocJc
methyleBe chloride fdichloromelhaae)
methyl unhthalate, 2-
4.IOE-03 1.20E-07
col avaibble
inadequate data
7.50E*3 2.10E-07
inadequate data
C
B2
D
B2
C
eavaee/lRIS
food/lRIS
/IRIS
water/I RJS
/IRIS
5/1/92
5/1/91
8/1/90
1/1/91
8/1/91
RALCAR.XLS10/14/94
-------
TABLE 4,2
TOjaciTV VALVES
POTENTIAL CARCINOGENIC EFFECTS
nick'l (soluble still not evaluated)
nitrophenol. o (nittophenol. 2-)
nitrophenol, p- (nilroeJienoU- nodala
PC8* - 7.70E+00 2.20E-04 B2
Dcnunonc. 4-mclhv] 2- nodal*
potassium
EH51S inadeonate data D
u-lracliloroeUiene ; Wdi°g
tricUorobenzene. 1,2,4- inadequue dau D
tricUofoetheiK I.IO^K :
a'nc inadequate dau D
nlul.uioii Roua (mBftR^aavVl frs/nfl)
anlhracene nodala D
bcnio(«)DVreK withdrawn B2
benzo{b)fluorantliene no dau B2
calcium
B2
D
D
iOE-03 Bl
OE-02 A to^
B2
D
B2
SF Basis/ dale
/IRIS _?/l/92
/IRIS 1/1/91
food^IEAST 3//9Z
/BUS 2/1/91
/IMS 12/1/90
inhalation: waler/IRIS 2/1/91
/IRIS 12/1/90
/IRIS 7/1/92
inhalation/IMS I/I/QI
/IRIS 12/1/89
/IRIS 8/1/91
mhalalion/IRIS 6/1/92
/IRIS 1/1/91
nvage/IRlS 3/1/91
/IRIS 12/1/90
FboMRIS 8/22/88
RALCAR.XLS10/J4/94
-------
TABLE 4.2
Toxicrrv VALUES
POTENTIAL CARCINOGENIC EW'UCTS
CHEMICAL
DDE
DDT
dicMoroaenzene, 1,2-
dichlocoethine, J,I»
dJchlDroclbene. J.I-
dichloroeihette, cii-1.2-
dichlcroethe&e. trans-1,2-
dfchloropropaae, 1,2-
diethylphthilate
dimethylpheBol. 2.4-
eodr ID aldehyde
ethyl benzene
KeptithJor
he uchlorobc • ze B c
iBdeood 23-c.cDpyrene
Slope
FadoT
no data
3.40E-01
no data
inadeqaiie dim
l^OE+00
no data
no data
no data
no data
eodaia
'
DO data
inadequate data
4.SOE+00
9.IOE+00
1.60E-+DO
DO data
Drinking Water
9.70E-05
5.0GE-05
1.30E-03
2.60E^)3
4.60E-(M
Weight of Evidence Type of
Classification Cancer (A}
B2
B2
D
C
C
D
B2
D
D
D
B2
B2
B2
B2
SFBaiii/
SFSoorce
food/1 RJS
food/IRIS
/IRIS
/IRIS
inhalation/IRlS
/mis
/IRIS
eavape/HEAST
/IRIS
/IRIS
/IRIS
. /IRIS
/IRIS
food/IRIS
/IRIS
/IRIS
date
online
8/22/88
5/1/91
1/1/91
10/1/90
2/1/91
12/1/90
31191
mm
8/1/91
12/1/90
1/1/91
4/1/92
4/1/92
12/I/9C
iron
taophofOQc
lead
inadequate data
DO data
C
B2
aavate/lRIS
food/IRIS
5/1/92
5/1/91
mas«e«tim
miapiaeie
melhvteoc chloride fdicHoromethane)
inadequate data
4.70E-07
D
B2
/IRIS
inhalation/IRIS
8/1/90
1/1/91
methyl naphthalene. 2-
methytpheaoK 2-
methyl phenol. 4-
fuffcthilene
otckcl
nitrooheaol, p- fnitrophecol. 4-1
PCBs
pealtaOBC. 4-methyl 2-
potauhim
pyreae
xeleBjam
iHver
* odium
le tr tcH orocthene
trichlsrobenzene 1^,4-
tnehkyoethine. 1,1,1-
trichl ococ then e
viAiHium (penioilde)
viByl chloride
xvIcDcs
zinc
inadequate data
inadequate data
no data
(soluble jails Dot evaluated)
no data
no data
DO data
nodaia
no data
inadequate data
oadat*
nodaU
inadequate be evaluated)
3.00E-01
inadequate data.
inadequate date
1.60&-Q5
8.40E.05
C
C
D
B2
D
D
D
D
D
D
D
D
C
A liver
D
D
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/IRIS
eavaste/IRIS
/ECAO
/IRIS
/HEAST
/IRIS
/IRIS
8/1/91
8/1/91
9/1/92
1/1/90
12/1/90
1 1/1/91
1/1/9
6/1/9
6/1/89
8/1 19'
3/1/9
9/l/9(
1/1/9
6/30/8
3//9!
3/1 »
2/1/9
RALCARJOLSIO/I4/94
-------
TABLES.!
FORMER RALSTON srre
suBcimoNic HAZARD INDEX ESTIMATES
CURRENT LAND USE • TRESPASSER
• , ' ; SDI
. . j. . • : SDl '.' Adjusted for RfD (snfcchrow'c)
CHEMICAL ,:?<•
fatt/kb-dair) Absorption
(nu/ksMla*)
Crilie»l:,> ..
. ' - Effect !-' ••;-'."-:
4V- • .'•' Pathway . Toul
- RfD source/ . Vfcdifytjil&tisiard' .ijk'" Halttrf ': ; '. lUzird
^--•RfdBasis .
Facto*-
.v': OnotJent IliY-:) Indatx" -:'."• '. lades: •
Elposure Pathway: Ineidenul Imestion of Surface Water While Wadinc
Acetone
Barium
Cadmium
Carbon Disulfide
Dichloroethene, 1,1-
Dichloroethene, Cil- 1 J-
Di chloroethene, Trans- 1 ,2-
Nickel
retrachloroethene
rotlRlK
rridiloroBhanc. l.l.t-
rrlchtoroethem
Xylene (toul)
Zinc
1.95E-06 No
3.48E-05 No
1.10E-06 No
9.86E-08 No
9.R6E-08 No
USE-OS No
2.22E-07 No
I.45E-06 No
I.73E-07 No
2.22E-07 No
7.40E-08 No
8.98E-07 No
7.40E-0! No
I.23E-OS No
Pathway Hazard Index
1.00E400
7.00E-02
5.00E-04 a
I.OOE-OI
9.00E-03
t.OOE-01
2.00E-01
2.00E-02
I.OOE-01
2.00E+00
9.00E-01
6.00E-03 «
4.00E+00
3.00E-OI •
increased liver/ kidney weight
NOAEL
proteinuria
feul toxfcity/rnatformations
liver lesions
decreased hermtocrlt, etc.
gavage/HEAST
epidemiology/HEAST
epidemiology/HEAST
inhalalion/HEAST
water /HEAST
gavage/HEAST
increase seram alk. phosphaUsc /HEAST
decreased body weight
hepatotoxtcity
liver and kidney weights
liver toxiciiy
hyperaetlvlty, ete.
blood anemia
foo*HEAST
gavage/HEAST
gavage/HEAST
oraWHEAST
/ECAO
g.vigwllEAST
/IRIS
1000
3
10
100
1000
3000
1000
300
1000
fooo
1000
100
3
I.95E-06
4.98E-04
2.19E-03
9.86E-07
.IOE-OS
.I5E-04
.IIE-06
.26E-05
.73E-OS
.I1E-07
8.22E-08
I.SOE-04
1.I5E-08
4.1SE-05
3.08E-03
Exposure Pathway: Dermal Absorption from Surface Water While Wadint
9artum
Cadmium
Carbon Disulflde
Dichloroetheu, 1.1-
DlcMocoedteiie, Trau-1 ,2-
Nickel
TctrachloroetheDe
Toluene
Trichloroethane, 1.1,1-
rrichloroethetn
Xylene (toul)
Zinc
4.24E-06 Yes
1.33E-07 Yes
2.88E-07 Y«
1.92E-07 Yes
2.70E-07 Yes
I.77E-07 Yes
1.01E-M Yes
I.22E-06 Yes
I.53E-07 Yes
I.75E-06 Yes
7.21E-07 Yes
I.52E-06 Yes
Pathway Hazard Indei
7.00E-02
5.00E-04 i
I.OOE-01
9.00E-03
2.00E-01
2.00E-02
I.OOE-OI
2.00E+00
9.00E-OI
6.00E-03 •
4.00E+00
3.00E-OI a
NOAEL
proteinuria
feul toxicity/malformatiotts
liver lesiotts
increase serum alk. phosphataie
decreased body weight
hepatotoxicity
liver and kidney weighu
liver toxicity
hyperactivity, etc.
blood anemia
epidemioloty/HEAST
epidemiology/HEAST
inhalatioti/HEAST
water/HEAST
/HEAST
foooTHEAST
gavage/HEAST
gavage/HEAST
oral/HEAST
/ECAO
gavage/HEAST
/IRIS
3
10
100
1000
1000
300
1000
1000
1000
100
3
6.06E-05
2.67E-04
2.88E-06
2.14E-05
1.35E-06
t.ME-06
l.OIE-03
6.0SE-07
1.70E-07
192E-04
1.80E-07
5.06E-06
6.70E-04
Exposure Pathway. Ineidenul Inxesilon of Sediment While Wading
Acetone
Anthracene
Arsenic
3arium
Cadmium
-montlum
Dichloroethene. Cil-l ,2-
:luorantheDe
Nickel
'vrene
3.33E-09 No
6.S8E-09 No
147E-07 No
1.28E-05 No
3.29E-07 No
8.7IE-07 No
2.08E-09 No
5.47E-08 No
8.38E-07 No
5.26E-08 No
l.OOE+00
3.00E+00
3.00E-04
7.00E-02
I.OOE-03 a
2.00E-02
I.OOE-OI
4.00E-OI
2.00E-02
3.00E-OI
increased liver/ kidney weight
NOEL
hyperpigmentation, etc.
NOAEL
proteinuria
NOAEL
decreased hematocrit, etc.
liver weights, etc.
decreased body weight
decreased kidney weip.hu
gavage/HEAST
gavage/HEAST
epWemiology/HEAST
epidemiology/HEAST
epidemiology/HEAST
water/HEAST
gavage/HEAST
gavage/HEAST
food/HEAST
tavaite/HEAST
tooo
3000
3
3
10
500
3000
3000
300
3000
3.33E-09
2.19E-09
8.22E-04
1.83E-04
3.29E-04
4.36E-05
2.08E-08
I.37E-07
4.I9E-OS
1.75E-07
RSKCVNON.XLS 10/14/94
-------
TABLE II
FORMER RALSTON SOT
SUBCHROMC HAZARD INDEX ESTIMATES
CURRENT LAND USE • TRESPASSER
SDI
SDt Ao(wedforRrD(.utJ>rt,,«)
CHEMICAL
rmt/rt-day) Absorption
(mi/kt-day'l
Critical
Effect
RlDwtm/ )
BID Bull
Paddf ..
Pathway Total
litzirt) Uiiifd (bunl
* Quo< - •• " Tftdcx" .: Tadex
Exposure Padiway: Inctdeatal Intesltc-a of Sediment While Wadint
frtchloraethcne
Zinc
3.29E-IO No
3.J2E-M No
PathwavHazard lades.
6.00E-03 a
3.00E-OI a
blood anemia
/ECAO.
/IRIS
3
Exposure Pathwar Derm.1 Ab.omtio« from Sediment While Wadini
Dichbraethene, Oi-U-
rrichtoroelhene
2.02E-07 Yes
3.80E-09 Yes
6.0IE-IO Yet
Pathway Hazard Index
l.OOEtOO
I.OOE-OI
6.00E-03 a
iicreased liver/ kidney weight
decreased rtematocrit, ete.
gavage/HEAST
gavage/HEAST
/ECAO
1000
3000
5.48E-08
I.I1E-05
1.43E-03
2.02E-07
3.80E-0!
I.OOE-07
3.4IE-07
Exposure Pathway: Incidental fniteclkin of Soil
Anthracene
Arsenic
3arium
bis<2-Eihylhexyl)Phtl»liie
taylbeozylphthalate
Cadmium
Chloroform
Hiromium
3iehloroethene. Cis-12-
nuoranthene
{exachlorobenzeoe
tfethylene Chloride
fickel
Pyrer*
Silver
retrachloroethene
Toluene
rrichloroediaie, 1.1.1-
rricNoroetheae
Xyfene (total)
UK
2.40E-06 No
2.0BE-04 No
3.S2E-07 No
2.I6E-08 No
I.05E-05 No
I.5IE-09 No
7.26E-05 No
I.33E-08 No
I.S1E-07 No
I.53E-08 No
2.07E-09 No
6.86E-OS No
1.9IE-07 No
179E-05 No
1.I9E-08 No
2.0IE-09 No
l.OOE-09 No
7.I2E-0! No
l.OOE-09 No
S.55E-04 No
Pathway Hazard ladex
3.00E*00
3.ME-M
7.00E-02
2.00E-02
2.00E400
I.OOE-03 a
I.OOE-02
2.00E-02
l.ooE-ni
•I.OOE-OI
S.OOE-04
6.0CE-02
2.00E-02
3.00E-OI
3.00E-03
I.OOE-OI
2.00E<00
9.00E-OI
6.00E-03 a
4.00E*00
3.00E-01 t
NOEL
hyperpigmentation. ete.
NOAEL
increased liver weight
increased liver weight
proteinuria
fatly cysts-liver
NOAEL
decreased hermtocril, etc.
liver weights, etc.
liver effeett
liver toxieily
decreased body weight
decreased kidney weights
argyria
hepatotoxieify
Kver and kidney weights
liver toxieily
hyperactivily, etc.
blood anemia
gavage/HEAST
epIdemioIogy/IIEAST
epidemiology/HEAST
foocUHEAST
foooVHEAST
eriidemioIogy/HEAST
oralcapculeAIEAST
waier/IIEAST
gavi|t/HEAST
gavage/HEAST
food/HEAST
water/HEAST
foodmEAST
gavage/HEAST
epIdemiologyAiHAST
gavage/HEAST
gavage/HEAST
oral/HEAST
/ECAO
favage/IRIS
/IRIS
3000
. 3
3
1000
1000
10
1000
500
3000
3000
too
100
300
3000
3
1000
1000
1000
100
3
- 6.03E-09
I.OIE-C3
2.97E-03
I.76E-05
I.OIE-OI
I.05E-02
1.5IE-07
3.63E-03
I.33E^)7
4.02E-07
2.04E-05
3.45E-OI
3.43E-03
6.3SE-07
5.5IE-03
1.I9E-07
l.OOE-09
I.I2E-09
I.I9E-05
2.5IE-10
I.85E-03
3.60E-02
Exposure Pathway: Dermal Absorption from Soil
Chloroform
Dichforoethene. Cii-1.2-
lexachtorobeazeoe
Methylene Chloride
ranchloroethene
'oluene
rrichloroethane. 1.1,1-
rrichloraethene
lylene (total)
'out Exposure Hazard Inde
2.75E-09 Yes
2.44E-OI Yes
3.9IE-07 Yes
5.04E-OI Yes
2.17E-08 Yet
3.67E-09 Yes
I.I4E-09 Yes
I.30E-07 Yet
l.ME-09 • Yes
Pathway Hazard Index
I.OOE-02
l.OOE-01
8.00E-04
6.00E-02
I.OOE-OI
2.00E*00
9.00E-OI
6.00E-03 a
4.00E«00
fatty cysts-liver
decreased hematocrit, etc.
liver effects
liver loxieity
hepatotoxicily
liver and kidney weights
liver toxicity
hyperactivity, etc.
oral capiule/HEAST
givigc/llEAST
food/1 [EAST
water/HEAST
gavagc/HEAST
(avage/HEAST
oral/HEAST
/ECAO
gavage/IRIS
1000
3000 .
too
100
1000
1000
tooo
100
2.75E-07
2.44E-07
4.97E-04
I.40E-07
2.I7E-07
I.ME-09
2.04E-09
2.17E-OS
4.S9E-10
5.20E-04
4 I7E 02
• =Bcctuse no tubdvontc RfD was iviitible, the chronic RID w«s used
RSKCVNON.XLS 10/14/94
-------
TABLE 5.2
FORMER RALSTON DISPOSAL SITE
SUBdHRONIC HAZARD INDEX ESTIMATES
CURRENT LAND USE - OFF SFTE RESIDENT CHILDHOOD EXPOSURE
:. Sftl
: Chemical fmnla-day)
Adjfor
Abfotp
(rabch/wilc) ConfMenee CiUal ' Rtt)B««l«/
Level
, "RID Scarce
Uaaiainty
Acetone 2.40E-04
Baton 1.09E-02
Butylphthilate.Di-n- I.20E-04
Chnmiium I.80E-04
DtchlOfoeUKne. Cti-1.2- I.20E-04
Mdhykne Chloride I.IOE-05
Nickel 3.72E-04
"etncMoroethene 4.79E-05
frichloroethine, 1,1,1- 1.20E-OJ
rrichloroeOiene 3.60E-04
Zinc 1.28E-02
No
No
No
No
No
No
No
No
No
No
No
1.00E440
7.00E-02
I.OOE+00
2.00E-02
I.OOE-OI
6.00E-02
100E-02
l.OOE-OI
9.00E-01
' 6.00E-03
3.00E-OI
tow
medfuni
low
low
medium
medhm
medium
medium
increased liver/ kidney weight
g»v«ge/HEAST
NOAEL YUemlotogy/llEAST
IncfCised mortality
NOAEL
decmeed hemitocrit, etc,
liver toxic Hy
decreased body weight
hepatotoxichy
liver toxfcHy
blood tnernla
food/HEAST
water/HEAST
givajt/HEAST
wa«er/HEAST
fcHxVHEAST
g.v,ge/HEAST
oral/HEAST
/ECAO
/IRIS
1000
3
1000
500
3000
100
300
1000
1000
1
Pathway Hazard Index
"oul Exposure Hazard Index
Pathway : Expoiun
i IiUJU'i] HuiLra . „ ',: , nazitil
2.40E-04
I.56E-OI
I.20E-04
8.99E-03
1.20E-03
2.00E-04
I.86E-OZ
4.79E-04
I.33E-05
5.99E-02
4.26E-02
2.88E-01
2 88E-01
RSKOFNOI XLSIO'14/94
-------
TABLE 5.3
FORMER RALSTON DISPOSAL SITE
CHRONIC HAZARD INDEX ESTIMATES
CURRENT LAND USE - OFF SITE RESIDENT UFETtME EXPOSURE
CD!
;'•'."• CW . Adjfor
Cheaictl. :; tanti-div) AbMie
RID
Confldence ;_ • CrtloJ ,,'" ,":}.^:-' 'WDBuli/ . /.=.".' Unetwil^
\ "-f «' . ,' ' „.; Pluiwxy-i • Expccurc
'-".;' nlutd ", ^- -nttinl ." Hmfd
fii'>0lic'u>
-------
t
TABLE S.4
FORMER RALSTON STTE
SUBCHRONIC HAZARD INDEX ESTIMATES
FUTURE LAND USE • ON SITE RESIDENTIAL CHILDREN
CHEMICAL
SDI i
SDI
Adj. for
Abcorp.
RfD . .
(nnjctonic). Confidence Citdctl
• (mtfot-tm'l Level ... Effort ••'»: .- -
:~: ,'• RID Bute/ / Ubc*(»toy t
>- • ROD Source .'• ftdot - ••-'•
.;. •_ ... Vi. •.;;. P*hw»y . .:;v ToW :
niZMu - - ' . niUni ^' ntXJku
OuoUent." .^ Index ''• Index • .
Childhood Exposure P««hwiy: Inxesllon of Drinkinr Water
Antimony
Arsenic
Barium
Beryllium
BromodichlwwTKtJmK
ButylphOulate.Di-n.
Cadmium
Chloroform
Chromium
DfcHoroettiine. 1.1-
Wchloroetnene. 1,1-
Dfchloroethene,Cl*-l,2-
Dkhloroeth«ne,Tnns-l,Z-
Ethylbenzeae
Manganese
Melhytene Chloride
Nickel
Selenium
Silver
Tetnchloroettiene
Tokiene
rrichknoerhene
Vinidhnn
Xylene (total)
Zinc
Path*
5.ME-03
4.32E-04
1.82E-02
I.50E-04
3.60E-04
I.20E-04
158E-04
3.00E-02
I.86E-03
7.I9E-04
1.026-02
I.08E+00
I.92E-03
3.60E-05
1.I4E-01
5.99E-04
142E-03
2.S8E-04
2.94E-04
8.39E-04
4.20E-04
3.I2E-OI
3.06E-03
I.80E-04
1.52E-02
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
4.00E-04
3.00E-04
7.00E-02
5.00E-03
2.00E-02
I.OOE+00
5.00E-M
I.OOE-02
2.00E-02
I.OOE+00
9.00E-03
I.OOE-OI
2.00E-01
I.OOE+00
l.OOE-OI
6.00E-02
2.00E-01
5.00E-03
S.OOE-03
l.OOE-01
2.00E400
6.00E-03
9.00E-03
4.00E+00
3.00E-01
low
medium
medium
low
medium
low
• high
medium
low
medium
low
low
medium
medium
medium
high
low
medium
medium
low
medium
i medium
longevity, blood glucose
hyperplgmentilion, etc.
NOAEL
NOAEL
raiil cytomegity
Increased mtxulity
pfotetaurit
fitty cyste-liver
NOAEL
NOAEL
liver lesions
dccRttcd hcrnttociii, etc.
jtcmsc Mtura iQc, pnosphttxsi
HvenUdney loxkky
CNSeffeds
liveftoxtehy
decreued body weight
setenosfc
trgyrii
btpalolosfchy
liver md kidney weights
decreased ruircyitlne
hypenctivity, etc.
blood inerhhi
.onWHEAST
ep)demk>togy/HEAST
epidemiology/HEAST
witer/HEAST
g>v>ge/HEAST
food/HEAST
epldemlology/HEAST
onl ctpsuteyHEAST
waler/HEAST
Wiil.tionmEAST
w«er/HEAST
gavigeJHEAST
/HEAST
givige/HEAST
epldemk>Iogy/HEAST
witer/HEAST
food/HEAST
epidemlotogy/HEAST
epldemlology/HEAST
givige/HEAST
givtgefHEAST
/ECAO
foodHEAST
givige/HEAST
/IRIS
1000
3-
3
100
1000
1000
10
1000
500
1000
1000
3000
1000
1000
1
100
300
3
3
1000
1000
100
100
3
rav Hazard Index
I.42E+OI
I.44E+00
2.6X1E-OI
3.00E-02
1.80E-02
1.20E-04
5.I5E-OI
3.00E400
9.29E-02
7.19E-04
I.SOEtOO
l.OSE+OI
9.59E-03
3.60E-05
I.I4E+OB
9.99E-03
I.2IE-01
5.75E-01
5.87E-02
8.39E-03
2.IOE-04
S.I9EWI
3.40E-01
4.49E-OS
5.0JE-02
8.58E+01
RSKONNO1.XLS 10/14/94
I of 6
-------
TABLE14
FORMER RALSTON SITE
SUBCHRONIC HAZARD INDEX ESTIMATES
FUTURELAND USE-ON SITE RESIDEOTTALaitUJREN
CHEMICAL J
SD1
SDI
Adj.fot
Atxot*.
RID
(svbctaonfc) Confidence Critical
(mta-dayi Level Effect
- FiOmy Total
RIDBnW Uncattlnty 'llanrd Iluarf Hatitd.
RfO&wrce Factor . OwiUeat Index . . Index
TMUhoodExposorePaftvnv: Incidental InteKlon of Soil
Anthracene
Arsenic
Sarium
bts(2-Elhylhexyl)Fhltiilalc
Btttytoeniylphlfialate
Cadmium
Chloroform
Chromium
Dlchloroethene, Cb-1,2-
Fluoramhene
:Iexachlorobenzene
Metfiylene Chloride
Nickel
Pyreae
Sliver '
Tetrachloroetltene
Toluene
Trtchloroetjiaae, 1,1.1-
TrlchloroeiheBe
Kylene (total)
Zinc
7.05E-07
9.37E-05
S.IOE-03
1.37E-05
8.42E-07
4.09E-04
5.S8E-CS
1.83E-03
3.20E-07
0.27E-06
«.37E-07
8.07E-OS
J.ogE-03
7.44E-06
I.09E-03
4.63E-07
7.84E-OS
3.9JE-08
2.78E-06
3.92E-08
tlffi-02
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
3.00E+00
3.00E-04
7.00E-02
2.00E-02
ZOOE+00
I.OOE-03 a
I.OOE-02
2.00E-02
I.OOE-01
4.00E-OI
8.ME-04
fi.OOE-02
2.00E-02
3.00E-OI
5.00E-03
l.OOE-OI
100E+00
9.00E-01
6.00E-03
4.00E+00
3.00E-01 a
low
medium
medium
medium
low
high
medium
tow
low
medium
medium
medium
low
low
medium
medium
medium
medium
NOEL
hypopignKtiUikxi. etc.
NOAEL
increased liver weight
Increased liver weight
prote'mura
fatty cysts-fiver
NOAEL
dccreasedhaitatoctM. etc.
liver weights, etc.
liver effects
nvertoifcify
itecreaied body weight
decreased kidney weights
argyria
hepitotoxlctty
liver and kidney weight
liver tonteliy
hypenclivHy, etc.
Mood anemia
gtvageAIEAST
epldtmlology/HEAST
eplcVmlolojy/HEAST
foooVHEAST
foodmEAST
epidemtelogy/HEAST
oral ca|>sule/IIEAST
water/HEAST
gavage/HEAST
gavage/HEAST
food/HEAST
water/HEACT
foodfflEAST
gavage/HEAST
epidemic logy/H EAST
gavage/HEAST
gavage/HEAST
onl/KEAST
/ECAO
gavage/IRIS
/IRIS
3000
3
3
1000
1000
10
1000
500
3000
3000
100
100
300
3000
J
1000
1000
1000
100
3
Pathway Hazard Index
2.3JE-07
3.12E-OI
I.KE-OI
6.S6E-04
4.2IE-07
4.09E-01
5.ME-06
I.42E-01
5.20E-06
I.57E-05
7.WE-04
I.34E-OS
1.34E-01
. 2.48E-05
2.I7E-OI
4.63E-OS
3.92E-08
4.35E-08
4.63E-04
9.79E-09
7.21E-02
I.40E-XK)
Childhood Exposure Pathway: Dermal Absorption from Surface Soil
Chloroform 2.79E-OS Yes I.OOE-02
DichloroetheM,Ct!-l,2-
fiexachlorobenzeoB
Methyfcne Chloride
relndiloroediene
Fohime
rrfchloroethane, 1,1,1-
rrfchloroethene
Kylene (total)
2.47E-07
4.03E-0*
J.IIE-07
2.20E-07
3.72E-08
1.S6E-08
1.32E-06
I.8CE-08
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
I.OOE-Ot
S.OOE-04
6.00E-02
1.ME-01
100E+00
9.00E-01
6.00E-03
4.00E+00
medium
medium
medium
medium
medium
medium
fatty cysts-liver
decreased hematocrit, etc.
Ever effect!
liver toxicity
hepalotoxkity
liver and kidney weights
liver toxfcity
hypenclivKyt etc.
oral eapsule/HE AST
gavage/HEAST
food/HEAST
water/HEAST
gavage/HEAST
gavage/HEAST
onl/HEAST
/ECAO
gavagelRIS
1000
3000
100
100
1000
1000
1000
loo
2.79E-06
147E-06
5.04E-03
8.5IE-06
Z20E-06
1.86E-08
2.07E-08
2.20E-04
4.65E-09
5.05E-03
Childhood Exposure Pathway: lacideotltl In«estlon of Surface Water ^ —
Acetone
Barium
Cadmium
Carbon Dlsulflde
Dfchtoroethene. 1,1-
Dfchloroethene.Cls-1.2-
Dfchtoroeihene. Trans- 1 2-
Nkkel
I.22E-05
Z18E-04
6.85E-06
«.1«E-07
6.16E-07
7.17E-05
I.39E-06
908E-06
No
No
No
No
No
No
No
No
I.OOE+00
7.00E-02
5.00E-M a
l.OOE-OI
9.00E-03
I.OOE-01
2.00E-01
2.00E-02
low
medium
high
medium
medium
low
Increased liver/ kidney weight
NOAEL
protein urn
fetal toxictty/malfomiatioiK
liver lesions
decreased hematocrit. etc.
ncrease seiun ilk. phosphitasi
decreased bodv weiflht
gavage/HEAST
epidemic togy/IIEAST
epidantology/HEAST
inhalallon/HEAST
water/HEAST
gavage/HEAST
/HEAST
food/HEAST
1000
3
10
100
1000
3000
1000
300
I.22E-OS
3.1IE-03
I.37E-02
6.I6E-06
6.85E-05
7.I7E-04 •
6.93E-OS
4.54 E-04
RSKONNOI.XLS 10/14/94
2 of 6
-------
TABLE 5.4
FORMER RALSTON SITE
SUBCHRONIC HAZARD INDEX ESTIMATES
FUTURE LAND USE - ON SITE RESIDENTIAL CHILDREN
.: SDI Adj. for (rotchroiifc) Confidence CriflMl '. -.""
retrachloroethene 1.08E-06 No I.OOE-0! medium
rotocne 1.39E-06
rrichloroethane. 1 . 1 .1- 4.62E-07
IrkhloroeuKne 5.61 E-M
Xytaie (total) 4.62E-07
Zinc 7.78E-05
No
No
No
No
No
Pathwav Hazard Index
Barium I.ME-05
Cadmium S.lSE-07
Carbon DtallMe I.11E-06
Dfchloroeftene, 1,1- 7.42E-07
Dkhloroflhcne.Trins-1,2- 1.04E-06
Nickel 6.83E-07
retnchloroemene 3.89E-06
toluene 4.69E-05
rrichloroetname, 1,1.1- 5.91E-07
rrichkxoelhene 6.75E-06
Xylan (total) 2.78E-06
Ztoe 5.85E-06
Ye*
Yes
Yes
Yes
Y«
Yes
Yet
Yes
Yes
Yes
Yes
Y«
ZOOEtOO
9.00E-OI
(S.OOE-03
4.00E+M
3.00E-OI
7.ME-02
5.00E-04
I.OOE-OI
9.00E-03
100E-OI
100E-02
l.nflE-OI
100E+00
9.00E.01
6.00E-03
4.00EfOO
3.00E-OI
medium
medium
a medium
i high
medium
medium
low
medium
medium
medium
medium
t medium
hepitotoxkHy
liver wid kidney weights
liver tojtlcity
hypenetivHy, etc.
blood uiemia
NOAEL
proleinurla
fetal toxicityAnilfonnitlttu
liver lesions
ncrease serum in. ptinsphinji
decreased body wdgM
hqutotoifcity
liver and kidney weights
liver toxicity
hyperacHvity.etc.
blood raemla
. • RID Bat'b/ ^ IFnwfWnty. '.
gavigeyHEAST
gavagemEAST
orat/HEAST
/ECAO
gavage/HEAST
/IRIS
cpldemlology/HEAST
cpldemlology/HEAST
inhilltkm/HEAST
water/HEAST
/HEAST
ftwoVHEAST
gavage/HEAST
givage/HEAST
oral/HEAST
/ECAO
gavage/HEAST
/IRIS
1000
1000
1000
100
3
3
10
100
1000
1000
300
1000
1000
1000
too
3
Pathway Hazard Index
Acetone 4.KE-OS No I.OOE+00 low
Anthracene 8.22E-08
Arscnte 3.08E-06
Barium 1.60E-04
CKbnhm 4.I1E-06
Chromiuni I.09E-05
DBhlo«eiheiie,Cii-U- 2.«OE-08
Fhionmhene 6.S3E-07
Nkket I.05E-05
Pyrene 6.58E-07
rrichlorocthrae 4.1IE-09
Zinc 4.15E-05
No
No
No
No
No
No
No
No
No
No
No
3.00E+00
3.00E-64
7.00E-02
I.OOE-03
2.0QE-02
I.OOE-DI
4;OOE-01
2.0CE-02
3.00E-OI
6.ME-03
3.00E-OI
low
medium
medium
• high
medium
low
medium
low
i medium
Increased liver/ kidney weight
NOEL
hyperpigmentattoa, etc.
NOAEL
pnitemufii
fatty cysts-liver
decreased henutocrit, etc.
liver weights, etc.
decreased body weight
decreased kidney weights
blood incmli
gavage/HEAST
gavage/HEAST
epUemk>k>gy/HEAST
epldemlology/HEAST
epIdemlology/HEAST
onlcapsvle/HEAST
gavage/HEAST
gavage/HEAST
food/HEAST
gavage/HEAST
/ECAO
/IRIS
looo
3000
3
3
1000
3000
3000
300
3000
3
PtthwivHiardlndot
Childhood Enposure Fithwiy: Deimil Absorption from Sedtaenl while Widta«
Acetone 7.BIE-07
DkhloroethtiM. Cts-U- 1.47E-08
rrkhloroelhene 2.32E-09
Yes
Yes
Yes
I.OOE+00
I.OOE-01
6.00E-03
low Increased liver/ kidney weight
decreased hemalocrit, etc.
gavage/HEAST
glvage/HEAST
/ECAO
1000
3000
Puhwiy Htzird Inrln
Foul Expoture Hizud Index
... ;. -.. - Pathway-.,- - -'Total
Hanird H«rird.-;v Hand
I.OSE-05
6.93E-07
5.I4E-07
9.35E-04
I.I6E-07
2.59E-04
2.34E-04
I.03E-03
I.I1E-05
8.ME-05
5.22E-06
3.4IE-05
3JJ9E-05
2.35E-06
6.57E-07
I.I3E-03
6.95E-07
I.9SE-OS
4.I6E-08
2.74E-08
1.03E-02
2.29E-03
4.IIE-03
5.45E-04
2.60E-07
1.71E-OA
5.ME-04
2.19E-06
«.85E-07
1.38E-04
1.79E-02
7.81E-07
I.47E-07
3.8HE-07
I.3IF.-06
RSKONN01.XLS 10/14/94
3 of 6
-------
TABLE 5J
FORMER RALSTON SITE
CHRONIC HAZARD INDEX ESTIMATES
FUTURE LAND USE • LIFETIME ON SHE RESIDENT
CD! , CO1
"..' "•••..'-.. . •--" • (drodc) " Adj.br
RID
(dvoftfc)
.Ifellme Exposure Pilhwiy: IniesHon orGroundinter
Antimony
Arsenic
Butan
Beryllium
Bromodichloroinettnne
Butylphlhllile.CH-B-
Cidmhmi
Chloroform
^hromium
Dfchloroediine, 1,1-
DfchlotoetheM. 1,1-
DlchlMotthetK, Cis-li-
Dkhloroeihe ne. Trim- 1.2-
ithyfbenzene
Manganese
rtefliylene Chloride
Nickel
Selenium
Silver
Tetrachloroetiiene
Toluene
rriditoroefliene
Vanadium
Xylene (loul)
Zinc
3.20E-03
2.4JE-W
1.03E-02
S.48E-05
Z03E-M
6.78E-05
I.46E-04
I.70E-02
I.OSE-03
+.07E-04
9.IJE-03
6.10E-OI
I.08E-03
2.03E-05
6.48E-02
3.39E-04
I.37E-03
I.63E-04
I.66E-04
4.75E-04
2.37E-04
I.T6E-01
I.73E-03
1.02E-04
8.58E-03
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
4.00E-04
3.00E-04
7.00E-02
5.00E-03
2.00E-02
l.OOE-01
J.OOE-04
I.OOE-02
5.00E-03
l.OOE-01
9.00E-03
I.OOE-02
2.00E-02
l.OOE-01
l.OOE-01
6.00E-02
100E-02
5.00E-03
5.00E-03
l.OOE-02
2.00E-01
6.00E-03
9.00E-03
100E-KH)
3.00E-01
CcofldeoM
low
medium
medium
low
medium
low
high
medium
low
medium
low
low
medium
medium
mediuu
high
low
medhim
medium
low
rncdhmi
longevity, bkwd {hKoM
hyperplgmtnuijon, etc.
NOAEL
NOAEL
ftnilcytomepty
incretstdmcxUlity
protetaurli
fittycysls-Iiver
NOAEL
NOAEL
liver lesions
decreued henutocrit, etc.
increase scrum ilk. (hosphitase
liver/kidney tolklty
CNSefTeds '
KverloxicUy
decreased body weight
selenosis
aigyrli
hepiloloitictty
liver uid kidney weigMJ
decreased htir cytttoe
hyperactivHy, elc.
blood anem'n
/'v'.-.;ji<.-.:..-. •!**» .--:-.:fe
ont/IRIS
epIdemWogydRIS
epl*mWojy/lRIS
wtler/IRlS
gavi|eJlRIS
rood/IRIS
epMemlologyftRtS
onlctpnileJIRlS
water/IRIS
WilIrtolVrlEAST
wtto/IRlS
gtvage/HEAST
/IRIS
givije/IRIS
cpidemlolojy/IRIS
wtter/IRlS
lood/IRIS
epidemiology /IRIS
epldemioK>ty/IRIS
jtvige/IRIS
gtvt§e/IRIS
/KM)
foodlRIS
gtvige/IRIS
/HEAST
1000
3%
3
100
1000
1000
10
1000
300
1000
1000
3000
1000
1000
1
too
300
3
3
1000
1000
100
100
10
.'£. •• v B' '•!»„ Pitfcwjy.,;^, . Tofftl
[tStJ,A -'- "i » jjl-'jjrj' " ''." '„ |t»..fvt " " "
EiKZUw,'-'' >',«' xiuflfl ;. „- .' • nutju
S.OIE+00
I.I4E-OI
1.47E-OI
1.70E-02
I.02E-02
S.7SE-04
2.92E-01
I.70E4W
2.10E-OI
4.07E-03
I.02E+00
6.10E40I
5.42E-02
2.03E-04
«.48E-01
5.«5E-03.
S.S5E-02
3J5E-02
3.32E-02
4.75E-02
1.19E-03
2.ME+01
1.92E-OI
5.09E-OJ
2.86E-02
I.04E+02
RSKONN01.XLS 10/14/94
4ofli
-------
TABLE 5.5
FORMER RALSTON SITE
CHRONIC HAZARD INDEX ESTIMATES
FUTURE LAND USE - LIFETIME ON SfTE RESIDENT
.- ' • CM
V (chronic)
CHEMICAL ':- .-•'• fm«ft«-daY)
Lifetime Exposure Pathway:
Antttracene
Arsenic
32flUm
bis(2-Elhy]liBxyl)Phtha!ate
ButylbenzylphOnlite
Cadmium
-hlwofottn
uhronttufli
Dichloroetheiie,Cb.l,2-
Ftuoranlhene
Flexaehlorabenzene
Wethylcne Chloride
Nickel
Pyrene
Silver
retfichloroelhene
relume
rrfchloroethaiw, 1,1,1-
rncntofoethene
Xylene (total)
Zinc
LifeUme Exposure Pathway:
Chloroform
D'KHoroethene, Clj-l J-
rleiachlorobenzene
Methykne Chloride
retnchloroethene
toluene
rrfchloroettitne, 1,1,1-
rrichloroethene
Xylene (loUl)
CD1
Adj. for
AbSOTD.
RfD
(chronic) Confidence Critfc.1 :
fmadUMhy) Level . Effect '::
RID BttbffUD Stm Uncertainty ^
• .. .. • '. Factor ••' '•
Pathway : ;.. Total
HftULfU ' . ' •flCCtfQ ... , HUCaWi
Ouolie»l •'.. laden • index -
Incidental Inaestion of Surface Soil
MXSE-07
2.73E-05
136E-03
4.00E-06
Z.45E-01;
I.I9E-04
l.TIE-OS
8.26E-04
I.52E-07
I.83E-06
I.86E-07
135E-08
7.80E-D4
Z17E-OS
3.I7E-04
I.35E-07
2.28E-OS
1.1JE-08
8.D9E-07
I.NE-08
«.30E-03
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
3.00E-01
3.00E-04
7.00E-02
2.00E-02
2.ME-OI
I.OOE-03
l.OOE-02
S.OOE-03
l.OOE-02
4.00E-02
R.OOE-04
6.00E-D2
2.00E-02
3.00E-02
S.OOE-03
LOOE-02
2.00E-01
9.00E-02
6.00E-03
100E+00
3.00E-OI
low
medium
medium
medium
low
high
medium
low
low
medium
medium
medium
low
low
Tnedhon
ntrahim
medium
NOEL
hypefpigin nilalion, etc.
NOAEL
increased liver weight
mcrettsed liver weight
pfotcinurli
fatty cysts-liver
NOAEL
decreased hematocrit, etc.
liver weights, dc.
liver effects
liver tox icily
decreased body weight
decnased kidney weights
*»8yri*
hepatotoiicMy
liver and kidney weights
Hver loxicity
hyperactivHy, etc.
blood anemta
gavage/IRIS
epidemiologyARIS
epldemiokigyARfS
food^RIS
food/IRIS
epldemlotogy/IRIS
oral capsule/IRIS
water/lRIS
gavage/HEAST
gavage/IRIS
foooVIRlS
water/IRIS
foodVIRIS
gavageARIS
epldemk>logy/IRIS
gavage/IRIS
gavage/IRIS
oral/HEAST
/ECAO
gavage/IRIS
/HEAST
3000
3
3
1000
1000
10
1000
500
3000
3000
100
100
300
3000
3
1000
1000
1000
100
10
6.85E-07
9.I1E-02
3.37E-02
100E-04
I.23E-OS
I.I9E-OI
I.71E-06
1.65E-OI
I.52E-05
4.J7E-D5
2.32E-04
3.92E-07
3.90E-02
7.23E-05
6.34E-02
I.35E-OS
I.I4E-07
I.27E-07
1.3SE-04
5.7IE-W
2.IOE-02
5.33E-OI
I.06E-08
9.39E-08
1.53E-06
I.ME-07
8.36E-0*
I.4IE-08
7.07E-09
5.0IE-07
7.07E-09
Yej
Yet
Yes
Yes
Yet
Yes
Yes
Y«
Yea
l.OOE-02
l.OOE-02
S.OOE-04
«.OOE-02
l.OOE-02
lOOE-01
9.00E-02
6.00E-03
2.00E+00
medium
medium
medium
medium
medium
medium
fairy cysts-liver
decreased hematocrit, etc.
liver effects
liver Ionic tty
hepaloloxicHy
liver and kidney weights
liver loxicity
hypencUviiy, etc,
oral capsule/IRIS
gavage/HEAST
food/mis
waler/rRIS
gavige/lRIS
gavage/IRIS
oral/HEAST
/ECAO
gavige/IR15
1000
3000
100
100
1000
1000
1000
100
Pathway Hamdlndex
Lifetime Exposure Pathway:
Acetone
Barium
Cadmium
Carbon Disulftde
Dtehtoroethene, l.l-
Dichlororttjene, Cis-1,2-
Dlcttloroethene, Trms-1,2-
Nickel
1.06E-INS
9.39E-06
1.92E-03
3.24E-OI!
8.36E-06
7.07E-08
7.86E-08
8.35E-05
3.54E-09
102E-03
IncWenUl Injiestton of Surftce W»ler
2.65E-M
4.75E-05
1.49E-W
I.35E-07
I.35E-07
1.36E-03
3.03E-07
I.98E-D6
No
No
No
No
No
No
No
No
1.ME-OI
7.00E-02
5.ME-04
l.OOE-OI
9.00E-03
l.OOE-02
2.00E-02
2.00E-02
low
medium
high
medium
medium
low
medium
increased liver/ kidney weight
NOAEL
proteinuria
fetal toxlclty/malfonnations
liver lesions
decreased hemaloeril, etc.
Increase scrum ilk. phosphause
decreased body weiorit
gavage/IRIS
epldemiok)0/lRIS
epidemiology /IRIS
bhalation/IRIS
waler/IRIS
gavage/HEAST
/IRIS
food/IRIS
1000
3
10
100
inoo
3000
1000
300
2.65E-05
6.79E-04
2.99E-03
I.35E-06
I.50E-05
I.56E-03
1 51E-05
9.9IE-05
RSKONNOI.XLS 10/14/94
5of«
-------
TABLE5J
FORMER RALSTON SITE
OIRONIC HAZARD INDEX ESTIMATES
FUTURE LAND USE • LIFETIME ON SITE RESIDENT
CpEMJCA|, *•''•" f
CDl
mnA^-drr)
CDl RfD
A«). (T)
Levtl
CrUisl
Effect
••:.'.. .: . . ftctor- .;:•>'
, • > - P»*»»)f -Tuttl
Quotient Index ,. "'index
Jfctlme Exposure Pi*w»y: lncHmu!lBi«t[onofS«rficcWiler
reuiehloroetheM
Fohiene
Frichloroelhtne, 1,1.1-
Frichforoewtene
Xylene(lotil)
Zinc
2.ME-07
3.0JE-07
I.OIE-07
1.23E-OS
I.OIE-07
1.70E-03
No
No
No
No
No
No
l.OOE-02
100E-OI
9.00E-02
«.OOE-03
2.00E+00
3.00E-OI
raediura
medium
medilum
hepitotaxkity
liver md kidney weights
nvcrtoilctty
hypencUvlty. etc.
blood memli
ginge/IRIS
gttige/IRIS
onl/HEA.TF
/ECAO
gavage/IRIS
/HEAST
1000
1000
1000
100
10
Ptlhwiy Hizinl Index
Lifetime Exposure Pathway:
Barium
Cidrnhni
Carbon DlrullWe
Dlchloroethene.i,l-
Dlchlonxtfieoe, Tmu-1 2-
Nickel
Fetnchloroethene
Toluene
FrichloroeUiine, 1.1.1-
Frlchloroethaw
Xylene (total)
Zinc
L3SE-OS
I.3IE06
I.I1E-W
104E-04
5.05E-OS
3.WE-05
5.68E-03
Dermxl Absorption from Surface Witer
3.33E-06
1.IIE-07
2.39E-07
1.39E-07
124E-07
I.47E-D7
8.37E-07
I.OIE-06
1.27E-07
1.45E-06
3.9SE-07
I.2oE-0$
Yet
Yes
Yet
Yet
Yet
Yet
Yet
Yet
Yet
Yet
Yet
Yet
7.00E-02
S.OOE-04
I.OOE-01
9.00E-OJ
2.00E-02
2.00E-02
l.OOE-02
100E-OI
9.00E-02
6.00E-OJ
2.00E400
3.00E-01
medium
high
medium
medium
low
medium
medium
medium
medium
NOAEL
protdnurb
fetil (oxlcuy/hiilformitlons
liver leclons
Increase serum lUc. phosptuttse
decretsed body wtljht
hepttotoxlcfty
liver md kidney weights
liver toxfcty
hypenctlvlty.ele.
blood inemhl
epldemlology/IRIS
epldemlologyJTRIS
InhtliUonyiRIS
witer/IRIS
/IRIS
(ood/IRIS
givige/IRIS
givige/miS
onl/HEAST
/ECAO
(tvige/IRIS
YHEAST
3
10
100
1000
1000
300
1000
1000
1000
100
ID
Pathway Hazard Index
^Ifetime ExBOture Pathway:
Acetone
Anthracene
Arsenic
tahmt
Cidmhm
-hronitttni
Dichloroethene, Cfa-1.2-
^hionntnaK
Nickel
Pyrene
Frichkiroethene
Zinc
3.03E-03
121E-04
2.39E-05
I.77E-OS
I.I2E-03
• 7.33E-06
8.37E-03
5.04E-06
I.4IE-06
2.42E-04
Z.99E-07
4.I9E-06
6.46B-04
IncMentil IntesHon of Sediment While WidbK
9.45E-09
1.S7E-OS
7.0IE-07
3.64E-03
9.35E-07
148E-0«
3.92E-09
I.55E-07
2.38E-06
I.50E-07
9.35E-IO
9.43E-06
No
No
No
No
No
No
No
No
Mo
Mo
No
No
I.OOE-OI
3.00E-OI
3.00E-04
7.00E-02
I.OOE-03
5iOOE-03
l.OOE-02
4.00E-02
2.00E-02
3.00E-02
6.00E-03
3.00E-01
low
low-
medium
medium
high
medium
low
medium
lov
Incre&sed liver/kidney weight
NOEL
hyperpigmentjtlon, etc.
NOAEL
protetaurii
fitly cysts-Over
decreased hemitocrit, etc.
liver weights, eto.
decretsed body weight
decreased kidney weight
blood uiemli
gtvige/IRIS
gtvige/IRIS
epideraiotogy/lRIS
epldemlology/IRIS
epidemiology /IRIS
onl capsuh/lRIS
givige/HEAST
gtvige/IRIS
foodlRIS
gmge/IRIS
/ECAO
/HEAST
1000
3000
3
3
1000
3000
3000
300
3000
10
Pathway Hizird Index
Lifetime Exmsure P«hwiy:
Acetone
DJchloroethstK. Cis-I.J-
Frfchloroeiiiene
9.45E-OS
6.23E-08
2.34E-03
5.JOE-04
0.35E-04
4.95E-04
5.92E-07
3.88E-06
I.I9E-04
4.98E-06
1.56E-07
3.I4E-03
4.4SE-03
Dermil Abtorptkn from Sediment while Widtne
I.91E-07
3.59E-09
3.67E-10
Yes
Yes
Yes
I.OOE-01
l.OOE-02
6.00E-03
low
miextt liver/ kidney weight
decreased htraXocrH. etc.
givige/IRIS
givige/HEAST
/ECAO
1000
3000
Pithwiy Hizird Index
Fotit Exposure Hizird Index
I.91E-M
3.39E-07
9.43E-M
2.3«E-06
l.ME+02
RSKONNOI.XLS IO/I4«4
6 of6
-------
CANCER RISK ESTIMATES
CURRENTLAND USE - TRESPASSER
CM
'•'•.' CDI idj.for
CHEMICAL • - - fna/kg-drvi Abaom
if
Wdjhlol
Cncer SFButsfSPSoorce :
Ctiemletl- ToUl ' Toul
.-nil*"'- ^::i.-Hlsk ,:':'• Risk"
Exposure Pltftwiv: IncfdenulIflKefltionotSoil
Arsenic 2.06E-07 No
3enzo(*)AnthncaH 7.73E-09 No
Benlo(i)Pyraie 7.73E-W No
Benzo(b)FhionMhene I.OIE-08 No
BnaoflOFhioraiKhene 7.73E-09 No
bii(2-E(hylhayl)Pt«h»l«e 3.01 E-08 No
Chloroform I.29E-IO No
Chtyser* I.40E-W No
HaKNoroberaerK I.40E-09 No
lndav>(l,2,3«))PytHK S.67E-09 No
Methylene Chloride I.77E-IO No
rriehloroethene 6.10E-09 No
Toulp.thw>,RI«k
Exrorare Pftthww: (nhiladon of Futilive Dun
Arsenic 1.90E-II No
Ctditwm 3.88E-17 No
Chlorofonn 5.58E-2I No
Chromlvm 2.69E-16 No
rricWoroahaK 2.63E-I9 No
ToulPtlhtnvRfak
I.7SE*00
7.30E41
7.30EtOO
7.30E-01
7.30E-02
I.40B-02
6.IOE-03
7.30E-03
I.60E+00
7.30E-OI
7.50E-03
1.IOE-02
5.00E40!
6.IOE«00
I.IOE-02
4.10E*01
1.60E«00
6.00E-03
A
B2
62
B2
B2
B2
B2
B2
B2
82
B2
A
Bl
82
A
B2
Innj/iHn wiientnhilitlon/IRIS
/IRIS
food/givige, ac/IRIS
IRIS
/IRIS
foodARIS
/IRiS
ARIS
/IRIS
wtlerARIS
/ECAO
lun(;ikln inhiMon; «w«4RIS
hhllation/IRlS
||e/IR15
hin| eptdemlototy/IRIS
/IRIS
/ECAO
3.6IB-07
3.66E-OI
7.39E-09
5.66E-IO
4.22E-IO
7.IIE-13
6.13E-1I
2.M&09
I.33E-I2
6.71E-11
4.38E-07
4.45E-I6
2.37B-I6
4.52E-22
1.IOE-14
9.67E-JO
I.58E-21
1.I7E-14
ixtatan Ptttvwiv: Derrul Absorction from Soil
Chlorofonn 2.36E-IO Yes
HatcWwobenielK 3.4IE-OI Yes
MeUiyleneOllorWe 4.32E-M Yes
rrlchloroedKM I.IIE-OI Ya
Twill P«ihw,T Risk
6.IOE-03
1.60E400
7.50E-03
t.lOE-02
B2
B2
B2
/IRIS
witer/IRIS
/ECAO
I.44E-I2
3.45E-OI
3.24E-I1
1.23E-IO
5.47B-OI
DicMorodhene, 1,1- 8.45E-09 No
MchloroalMiw 7.70E-0! . No
Vinyl Chloride 2.28E-07 No
ToulPiriwivRlik
t.lOE-02
I.90E+00
C
A
InhllitlonlRIS
/ECAO
lun||livet foodmEAST
5.07E-09
I.47E-IO
4.33B-07
4.39 B07
2XDocureNihwiv: Dermil Absorpikm from Surfice Wtter while Widins
DichloiwOww, 1,1- I.65E-CU Y«
IHchloroelhaic I.50E-07 Yes
Vinyl Chloride 2.02E-07 Yei
ToulPithwivRbk
e.OOE-01
I.IOE-02
1. WE tOO
C
A
InluhtMIRIS
/ECAO
lung; liver tbod/HEAST
9.S9E-09
I.63E-09
3.S3E-07
3.96E-07
Btnonire nihwiv: Incidental Incestion of Sediment while Widini
Anenlc 1IIE-0! No
Benra(i)Amhneene I.97E-09 No
Benzo(i)Pyrene 1.69E-09 No
ienzo(b)Fluonnthene I.97E-09 No
Benzo(k)Fluonnthene 1.1SE-09 No
Chry«eM 1.S3E-09 No
[rxlOTO(l,2.3-cd)Pyrcne IS.20E-IO No
rricWoronhme 2.82E-11 No
Toul Pithmv Risk
I.7SE+M
7.ME-OI
7.30E»00
7.30E-OI
7.30E-OJ
7.30EJ13
7.3QE-OI
I.ICE.02
A
B2
B2
B2
B2
B2
B2
luni/skln witer; Inhiliilon/IIUS
/IRIS
faod/givige, eteJIRIS
/IRIS
URIS
/IRIS
/IRIS
/ECAO
3.70E-OS
I.44E-09
I.23E-OS
I.44E-09
I.ME-II
1.34 E-II
4.53E-IO
3.IOE-I3
5.28E-OI
EIIKMUK mihw«v: Deraiil Absolution from Sediment while Wadbri
rricHoroelhenc 5.15E-II Yes
Toul Ptthwiy Rbk
Toul ElDosure Rbk
I.IOE-02
/ECAO
S.66P..13
5.W5IH3
I.3IE-06
RSKCVCAR.XLS 10/14/94
-------
TABLES.?
FORMER RALSTON DISPOSALStTE
CANCER RISK ESTIMATES
CURRENT UNO USE-OFF SITE RESIDENTS
CHHMICAl.
Methylene Chloride
rrichloroelhene
Arsenic (mg/kg)
Cadmium (mg/kg)
Chloroform
Chromium (mg/kg)
HexichlorobeineiK
rrichloroethene
Lifetime Exposure Pathway; li
Methylene Chloride
rrichlotoethene
Lifetime Exposure PathwayjJ
Arsenic (mg/kg)
Cadmium (mgfltg)
Chloroform
Chromium (mg/kg)
Heuchfarobenzene
Trichloroethene
CDI
•V Ortt/kf-day)
'1.03E-06
3.08E-05
1.39E-16
6.06E-16
8.7IE-20
4.20E-IS
9.43E-I9
9.43E-19
Total Pathway Risk
igeition of Drinking Water
1.71E-06
5.13E-05
Total Pathway Risk
nhahaionoflugiiivedua
I.S5E-16
6.75E-16
9.70E-20
4.67E-I5
I.05E-I8
4.58E-18
Total Pathway Risk
CDI
idjfor
Absorp.
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
SF
(mg/kg-day)-!
7.50E-03
1.10E-02
5.00E+OI
6.10E+00
8.10E-02
4.IOE+01
I.60E+00
6.00E-03
7.50E-03
l.tOE-02
5.0CE+01
o.IOH+00
8.IOE-02
4.10E+01
1.60E+00
6.00E-03
Wufhl
ef Typeof
E^deoce " -'• Caicer
B2
A lung; skin
Bl
B2
A lung
B2
B2
A lung: skin
BI
B2
A lung
B2
/•'.' •' • '
SF Bisu/SF' Source L. ; ;
water/IRIS
/ECAO
.
inhililion; water/IRIS
inhalation/IRIS
gavage/IRIS
epidemiology/IRIS
/IRIS
/ECAO
water/IRIS
/ECAO
inhalation; watei/IRIS
inhalation/IRIS
gtvtge/IRIS
epidemiology/! RIS
(IRIS
/ECAO
Chemie«!;j total ^
Specific ," -Path»«y
Risk ;. Risk
7.7IE-09
3.39E-07
3.47E-07
6.94E-15
3.70E-I5
7.05E-2I
I.72E-13
I.51E-18
5.66E-2I
I.83B-I3
I.25E-08
5.64E-07
5.77E-07
7.73E-I5
4.I2E-I5
7.8SE-21
1.92E-I3
1.ME-I8
2.75E-20
2.03E-I3
ToUl
Eiposure
Risk
3.47E-07
5.77E-07
RSKCAOF1.XLSIWI4/94
-------
TABLE 5.1
FORMER RALSTON sm
CANCER RISK ESTIMATES
FUTURE LAND USE • ON SITE RESIDENTS
GDI
... , ! CM Adj. lot
CHEMICAL : •
Sf
rmt/kiMUv) Ahtom frnt/kt-rkvVi
Wdiht
of .
Svldcno
.... at l^' v- ;".'"' •.
Caneej*.'' SFfi^s/SI1 Source •
Cheirieii ; , .-Tout •., ;.| ; .-. Towl
..Specific ••'• '; •..' PtAwiyy i i Etrjonre
• Kitk '.**{". -K1A'. :::''t?j:Vftisk- :,
Childhood Exposure Pathway: Intestion of Dtinkine Water
Arsenic
lenzetK
leryllhini
1 rofnodtcMocomctlmne
Zhlorofotrn
Dichloroelhene, 1,1-
Methylsne Chloride
rrlchlofoethene
Vinyl Chloride
3.70E-05
I.39E-04
I.2SE-05
3.08E-05
157E-03
1.39E.03
5.14E-05
2.67E-02
I.08E-02
No
No
No
No
No
No
No
No
No
I.75E+00
190E-02
4.30E+00
I.30E-01
6.IOE-03
6.00E-01
7.50E-03
I.IOE-02
1.90E+00
A
A
62
62
B2
C
B2
A
lung/skin witir, InhilttionlRIS
leukemit epldemlolo{y/IRIS
inluUtion/lRIS
|iv<|e/TRIS
|>vi|e/IRIS
Inhitellon/lRIS
*l>te
Chloroform
Chrysene
Heuchlorobeazene
ln*no(l,2,3-cd)Pjrrme
Meihylaie Chloride
rrichloroethene
6.47E^)5
4.02E-06
5.52E-05
4.01E-OS
I.57E-05
I.32E-04
3.I5E-07
2.94E.-04
2.05E-02
1IBE-02
Incidents! Incestion of Soil
«.03E-M
3.02E-07
3.02E-07
3.95E-07
3.02E-07
1.KB-06
5.04E-09
3.27&07
5.46E-OS
2.60E-07
«.9JE-09
2.3BE^)7
No
No
No
No
No
No
No
No
No
No
No
No
1.75E400
7.30EJJ1
7,30E*00
7.30E-OI
7.30E-02
I.40E-02
6.10E-03
7.30E-Q3
l.MEtOO
7.30E-01
7JOE-03
1.10E.D2
A
B:
62
62
62
B2
62
B2
62
B2
B2
luni/skln mter. InhiliUon/IRIS
/IRIS
food/|«vi|c, elcJIRIS
/IRIS
/IRIS
food/IRIS
|»»ge/IRIS
/IRIS
/IRIS
/IRIS
mter/TRIS
/ECAO
Childhood Exooure Piihwiv:
Arsenic
Cidmhim
Chloroform
Chromium
HeMchloroberaene
rrichloroethene
I.4IE-05
2.2IEJD7
12IE-OS
2.HE-07
12IE.OJ
1.65EJM
3.07E-I1
Z39B-09
S.73E-OI
I.90B-07
5.I9E-II
2.62B-09
I.7IE-05
Inhilnlon of Fugitive Dust
1.39E-I6
6.06E-I6
J.71E-20
4.20E-I5
9.43E-I9
4.11E-1I
No
No
No
No
No
No
5.00E+01
6.IOE»00
I.IOE-02
4.10E*01
1.60E«00
6.0QE-03
A
Bl
B2
A
B2
lung; skhllnhilitlon; wiler/IRIS
InhihtlonnRIS
g«vigc/lRlS
lung epldemiolo|y/IRIS
/IRIS
/ECAO
Toul P«thwiv Risks
Childhood Exposure Pithwm:
Chloroform
Hatchlorobcnzene
Methylene Chloride
rrichloroethene
6.94E-I5
3.70E-I5
7.0SE-2I
I.72E-I3
l.JIE-II
2.47E-20
I.S3B-13
2.39E-09
3.45E-07
4.3IE-OI
I.I3E-07
Yes
Yes
Yes
Yes
6.10E-03
I.MEtOO
7.50E-03
I.IOE-02
B2
B2
B2
l
-------
TABLE 5.1
FORMER RALSTON SHE
CANCER RISK ESTIMATES
FUTURE LAND USE • ON SHE RESIDENTS
CHEMICAL
CW Wdj*
CM Ad]', for SP of
(tnAt-Ant At«n>. (rrt^t-drrVI EvIderKe
Of
Ctnctr SF Buto/SF Soufcc
Hi* KM:
Toll!
Expuoujt
• Rid
Childhood Exposure Pathwtr: IncidmUl IniteiUon of Surfice Wnw v<6 lie WnJini
rrichloreethcne
Vinyl Chloride
4.IIE-07 No
I.42E-06 No
Toul Pithwiv It bk<
1.10641
1.90E*00 A
/ECAO
ICTII; llvtr food/HEAST
5.MB-09
2.70EJ16
174E-06
niUdhoodEirxHwePilhwiv: DenmlAHorntlonrromSutficeWMrr-iiMleWidint
Dldlloroethaic, 1,1.
rrichlorocthcnc
Vinyl Chloride
Ihildhood ExpMure Pilhw*
Arsenic
Bcnzo(i)AntotcetK
BennHbJFIuorinthene
Chrytene
jidcno
-------
TABLES.!
FORMER RALSTON SITE
CANCER RISK ESTIMATES
RmJRE LAND USE - ON SITE RESIDENTS
CHEMICAL
Lifetime Exposure Pithwav:
BaizoOOFIuorwtheM
bls(2-EthylhexyI)Phiht1ite
rhlofoform
Chryiene
lex icnloTobcnzene
lndeno(l,2,3-cd)Pyrene
MeUiylene Chloride
rrichloroethene
Lifetime- Exposure Pithwtv:
Arsenic
Cidmtum
Chloroform
Jhromium
facschlorobenzefw
rrichioroetheftc
Lifetime Exposure Pwhway
Hcxichlorobenzene
Methylene Chloride
rrichloroethene
Lifetime Exposure Pitnwi v:
Dichloroethene, 1.1-
rrichloroethene
Vinyl Chloride
Lifetime Exposure Pithnv:
Dichloroethene. 1,1-
rrichloroethene
Vinyl Chloride
Lifetime Exposure Pi*w«v:
Arsenic
Bouo(i)Anihncene
Ben»(«)Pyrene
9enzo(b}Huorsnthene
Benlo00Fluor«nthH«
Chryiene
[nv»|e. MC./IRIS
/IRIS
/IRIS
/IRIS
/IRIS
/ECAO
I.65E-09
3.85E-07
I.43E.07
5.57E-09
4.78E-08
5.57E-09
3.34E-10
5. HE- 11
I.7SE-09
1.20E-I2
2.D4E-07
Dermil Absorption from SedlmenEs while WsdinK ' ,„.,.
7.51 E-ll Yes
Toisl Pilhwiy Risks
I.IOE-02
/KCAO
8.26E-I3
I.26R.I3
3.89E-02
RSKONCRI.XLS 10/14/94
-------
TABLE 1
SUMMARY OF COSTS FOR REMEDIAL ALTERNATIVES
FORMER RALSTON DISPOSAL SITE- CEDAR RAPIDS, IOWA
Alternative
No.
1
2
3
4
5
Description
No Action
Natural Attenuation with Institutional Controls,
Monitoring, and Maintenance of the Cap and Creek
Bank Stabilization
Natural Attenuation with Institutional Controls,
Monitoring, and Maintenance of the Cap and Creek
Bank Stabilization, Devonian Groundwater
Extraction and Treatment
Natural Attenuation with Institutional Controls,
Monitoring, and Maintenance of the Cap and Creek
Bank Stabilization, Devonian and Silurian
Groundwatcr Extraction and Treatment
Natural Attenuation with Institutional Controls,
Monitoring, and Maintenance of the Cap and Creek
Bank Stabilization, Devonian and Silurian
Groundwater Extraction and Treatment Over Entire
Area of VOC Plume
Capital
Cost
$ 0
$ 0
$ 96,140
$223,600
$801,300
O&M
Cost
$ 0
$ 32,780
$352,500
$407,700
$492,800
PNW
Cost
$ 0
$ 566,800
$6,192,000
$7,274,000
$9,324,000
O&M = Operation and Maintenance
PNW = Present Net Worth
-------
TABLE 2
ALTERNATIVE 2
OPERATION AND MAINTENANCE COSTS
FORMER RALSTON DISPOSAL SITE- CEDAR RAPIDS, IOWA
Item
Quantity Unit
Unit Cost Extended Cost
A. Monitoring
1.
2.
Sampling and Analysis
Replace Pumps (estimate I/year)
. 1 Lump Sum
1 Lump Sum
S
$
15,000
1,500
$
$
15,000
1.500
B. Cap Maintenance
1.
Z
3.
Routine Maintenance
Repair Fence, Gate, Etc.
Erosion Repair, Reseeding
C. Reporting
1 Lump Sum
1 .Lump Sum
1 Lump Sum
1 Lump Sum
$
S
S
$
2,500
1,500
3,000
5,000
Subtotal
15% Contingency
TOTAL
S
$
S
$
S
$
$
2,500
1.500
3.000
5,000
28,500
4,275
32,780
Notes:
Lump Sum costs for one year.
Total extended cost rounded to four significant digits.
-------
TABLE 3
ALTERNATIVE 2
PRESENT NET WORTH COSTS
FORMER RALSTON DISPOSAL SITE- CEDAR RAPIDS, IOWA
Year
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Capital Cost
$0
$0
SO
$0
so
so
so
so
so
so
so
so
so
so
so
$0
so
so
so
so
so
$0
$0
$0
so
so
so
so
so
so
$0
O&M Costs
S 0
S 32.775
$ 32,775
S 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
S 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
Total
S 0
$ 32,775
$ 32,775
S 32,775
$ 32,775
$ 32,775
$ 32,775
S 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32,775
S 32,775
$ 32,775
$ 32,775
$ 32,775
S 32,775
$ 32,775
$ 32,775
$ 32,775
S 32,775
$ 32,775
$ 32,775
S 32,775
$ 32,775
$ 32,775
$ 32,775
$ 32.775
$ 32,775
S 32,775
$ 32,775
PAV Factor
1
0.9615
0.9245
0.889
0.8548
0.8219
0.793
0.76
0.7307
0.7026
0.6756
0.64%
0.6246
0.6006
0.5774
0.5553
0.5339
0.5133
0.4936
0.4746
0.4564
0.4388
0.422
0.4057
0.3901
0.3751
0.3607
0.3468
0.3335
0.3206
0.3083
TOTAL
Present Net Worth
$ 0
S 31313
S 30,300
$ 29,137
S 28.016
$ 26,938
S 25,991
S 24,909
S 23,949
$ 23,028
S 22,143
S 21,291
$ 20,471
$ 19,685
S 18,924
S 18,200
S 17,499
S 16,823
S 16.178
$ 15,555
$ 14,959
$ 14382
S 13.831
$ 13,297
$ 12.786
$ 12.294
$ 11.822
S 11,366
$ 10,930
S 10,508
$ 10.105
$566,800
Note: Total extended cost rounded to four significant digits.
PAV * Present Worth
O&M s Operation and Maintenance
-------
-------
-------
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