United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R07-90/040
September 1990
Superfund
Record of Decision:
White Farm Equipment
Dump, IA
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5OZ72-101
REPORT DOCUMENTATION 1" REPOATNO. I ~ 3. Reclplentl AcC888ian No.
PAGE EPA/ROD/R07-90/040
4. TIll end ..... 5. Report 0818
SUPERFUND RECORD OF DECISION 09/28/90
White Farm Equipment Dump, IA
First Remedial Action - Final I.
7. Aulhor(l) 8. P8rfonnlng Orglnlatlon ~ No'
8. PiIrfonnlng Org8lnla.on ...... IIId AddIM8 10. PtojlcllTl8klWoril Unit No.
II. ContnCl(C) or Grent(G) No.
(C)
(G)
1~ Spon8oring Orglfllullan"""l1111 Addr8s8 13. Type 01 RIpOI'I . P8riocl CoWNd
U.S. Environmental Protection Agency 800/000
401 M Street, S.W.
Washington, D.C. 20460 '"
15. Suppl8mentuy No...
I&. All8tr8ct (LImIt: 200 _Ida,
The 20-acre White Farm Equipment Dump site is an active landfill near the north border
of Charles City in Floyd County, Iowa. The site lies within the 100-year floodplain of
the Cedar River in the former location of a sand and gravel quarry, and borders
farmlands to the west, north and east with residential areas to the south of the site.
Drainage from the site toward the northwest and south feeds into adjacent wetland areas.
The Charles City municipal wells, located 700 feet east of the site, obtain water from
the deep, confined Cedar Valley aquifer. Additionally, six shallow drinking water wells
that draw from an uncontrolled water table are 1,000 feet downgradient from the site.
Intermittently since 1971, approximately 650,000 cubic yards of wet scrubber sludges,
foundry sands, baghouse dusts, and other industrial wastes were disposed of on site. In
1984, to assess the environmental impact of this disposal, the State required the
installation of four ground water monitoring wells. Site assessments in 1985 and 1986
revealed ground water contamination and documented that elevated metal levels were
present in the shallow alluvial aquifer in close proximity to the municipal wells. The
primary contaminants of concern affecting the soil, debris, and ground water are VOCs
including benzene and toluene; and metals including arsenic, chromium, and lead.
(See Attached Page)
17. ~t An8Iy8Ia .. DMcrIpIDi8
Record of Decision - White Farm Equipment Dump, IA
First Remedial Action - Final
Contaminated Media: soil, debris, gw
Key Contaminants: VOCs (benzene, toluene), metals (arsenic, chromium, lead)
b.~T-
Co C08A T1 RaldlGrCMlp
18. AV8II8IIIIIy SI-..ent ". Securfty 0... (1hIa A8por1I 21. No. of ....
None 54
20. Securfty CI888 (1hIa Page) 22. PrIc8
None
I Z12 (4.71)
(Sea A~Z38.1')
s.. ""trucll- 0" R.-
(FOfIII8fty NT1~)
~IofCo_C8
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EPA/ROD/R07-90/040
White Farm Equipment Dump, IA
First Remedial Action - Final
Abstract (Continued)
The selected remedial action for this site includes regrading and covering the landfill
with an impermeable layer of topsoil and vegetation to prevent contaminant infiltration,
leaching, run-off, and erosion; ground water pumping and treatment by air stripping
followed by onsite discharge of treated water; controlling air emissions by carbon
adsorption with offsite disposal of residuals; monitoring metal contaminant levels and
adding a metals treatment train as needed; ground water monitoring; and implementing
site access restrictions and institutional controls, including deed restrictions. The
estimated present worth cost for this remedial action is $2,352,121, which includes an
annual O&M cost of $89,345 for years 1-5 and $35,865 for years 6-30.
PERFORMANCE STANDARDS OR GOALS: The concentration of benzene in ground water will be
reduced and maintained below 1 ug/l (State standard).
~
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RlCORD OP DBCIIION
roR
THE nITE PARK BgUIPKENT COMPANY DUHP lITE
CHARLES CITY, IOWA
Prepared by:
u.S. ENVIRONMENTAL PROTECTION AGENCY
DGION VII
September 28, 1110
"
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DECLARATION POR THE RBCORD OF DECISION
~ ~ ~ Location
White Farm Equipment Company Dump site
Floyd County, Iowa
Statement Qf Basis ~ PurDose
This decision document presents the selected remedial action
for the White Farm Equipment Company Dump Site, in Floyd County,
Iowa, which was chosen in accordance with the requirements of the
Comprehensive Environmental Response, Compensation, and Liability
Act of 1980 (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act of 1986 (SARA) and, to the extent
practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP). This remedial action decision is based
on the administrative record for this site.
The Iowa Department of Natural Resources (IDNR) concurs with
the selected remedy.
Assessment Qf ~ ~
Actual or threatened releases of hazardous substances from
this site, if not addressed by implementing the response action
selected in this Record of Decision (ROD), may present an
imminent and substantial endangerment to public health, welfare,
or the environment.
DescriDtion '21 ~ Selected Remedv
~
This final remedy addresses remediation of groundwater,
soil, and landfill material contamination by eliminating or
reducing the ri.ks posed by the site, through treatment in the
case of groundwater, and engineering and institutional controls
for the r...1nder of the site.
The ..jor components of the selected remedy include:
Institutional controls including perimeter fencing and deed
restrictions on well installations and property use;
.
.
Engineering controls including regrading and covering the
landfill with an impermeable layer of topsoil and vegetation
to reduce transport of contaminants through infiltration,
leaching, run-off and erosion;
.
Installation of additional groundwater monitoring wells and
co11ection of analytical data for design purposes;
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• Placement of extraction veils, a treatment facility (air
stripper), and discharge conveyance to Hyers Creek;
• Extraction and treatment of contaminated groundvater until
the concentration of benzene in groundvater is reduced and
maintained belov l part per billion (ppb);
• Discharge of treated groundvater to Hyers Creek under a
National Pollutant Discharge Elimination System (NPDES)
permit;
• Addition of a metals treatment train should monitoring
indicate that Safe Drinking Water Act Maximum Contaminant
Levels (MCLs) and lova Groundvater Action Levels (IGALs) for
metal contaminants are not being met;
• Inspection and maintenance of perimeter fencing, the landfill
cover and vegetation, and the groundvater treatment facility;
and
• Long-term groundvater monitoring.
Declaration of Statutory Determinations
The selected remedy is protective of human health and t
environment, complies with Federal and State requirements th
are legally applicable or relevant and appropriate to the
remedial action, and is cost-effective. This remedy utilizes
permanent solutions and alternative treatment (or resource
recovery) technologies to the maximum extent practicable for this
site. One of the principal threats at the site, contaminated
groundvater, vill be addressed through use of extraction and
treatment technology. Hovever, treatment of the landfill
materials vas not found to be practicable since the landfill
materials are of large volume and pose a relatively lov long-tern:
threat, and therefore this remedy does not satisfy the statutory
preference for treatment with respect to the landfill materials.
The engineering and institutional controls included in the
•elected remedy will adequately and reliably manage and contain
the wastes left in place.
Because this remedy will result in hazardous substances
remaining on site above health-based levels, a reviev vill be
conducted within five years after commencement of remedial actio:
to ensure that the remedy continues to provide adequate
protection of human health and the environment.
,-nl 2"lbf 9-zs
jAortitr Kay ' Date
Regional Administrator
U. S. EPA, Region VII
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DBCISION SUKKARY
1.
~ Location ~ Desc~iDtion
The White Farm Equipment Company (WFE) Dump Site occupies
approximately 20 acres near the north border of Charles City in
Floyd County, Iowa. The site lies within the 100-year floodplain
of the Cedar River in the former location of a sand and gravel
quarry. The site borders farmlands to the west, north, and east.
Residential areas lie to the 80Uth of the site (Fiqure 1).
Drainage from the site toward the northwest and south feeds
into adjacent wetland areas. Drainage through the wetlands to
the south discharges into Hyers Creek approximately 2100 feet
southwest of the site. Hyers Creek joins the Cedar River
approximately 2500 feet southwest of the site. No endangered
species are found in the area.
Groundwater exists in two separate layers at the site:
1) the upper unconfined water table: and 2) the deeper confined
Cedar Valley aquifer. The Charles City municipal wells, which
are located 700 feet east of the site, draw Jrinking water from
the deeper confined aquifer for residents of Charles City
(population 8,878, U.S. Census 1980). In addition, there are six
downgradient shallow drinking water wells within 1000 feet of the
site which draw from the upper aquifer. In the vicinity of the
site, it is believed that the two aquifers are not hydraulically
connected. Both the upper water table aquifer, and the lower
confined Cedar Valley aquifer are designated Class I.
2.
~ Historv ADd Enforcement Activities
~
WFE has disposed of approximately 650,000 cubic yards of wet
scrubber sludges, foundry sands, baghouse dusts, and other
industrial wastes at the site on an intermittent basis since
1971. Allied Products Corporation presently owns WFE.
In 1984, the Iowa Department of Environmental Quality (IDEQ)
required WPE, who had leased the aite, to install four
groundwater monitoring wells at the site to determine whether
adverse environmental impacts had occurred from the dumping
activities. WFE monitored these wells on a semi-annual schedule
for potential site contaminants selected by the IDEQ including
lead, zinc, and trichloroethylene. This sampling effort found no
major groundwater impacts from potential contaminants at the
site.
In 1985, the U.S. Environmental Protection Agency Region VII
(EPA) performed a Preliminary Assessment (PA) of the site. The
PA suggested that lead, cadmium, and phenols may be among the
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\
[:)
AQURE1
SITE LOCAT1ON
CHARLES CITY, DOWA
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3
contaminants of concern at the site. EPA found wastes in contact
with groundwater at a depth of five to ten feet below land
surface. In 1986, the EPA Field Investigation Team (FIT)
conducted sampling at the site. This effort documented releases
of lead and chromium to the shallow alluvial aquifer in close
proximity to the Charles City municipal wells. As a result of
the investigation, EPA proposed the site for inclusion on the
National Priorities List (NPL) in June 1988. The site was placed
with final status on the NPL on Auqust 30, 1990.
On october 5, 1988, EPA inspected the White Farm New Idea
Equipment Company facility in Charles City, Iowa under authority
of Section 3007 of the Resource Conservation and Recovery Act
(RCRA). As part of this inspection, EPA examined the materials
being disposed of at the landfill. This inspection concluded
that no hazardous wastes were present in the solid wastes being
disposed of at the site.
White-New Idea still disposes of solid wastes at the site.
On February 15, 1990, the Iowa Department of Natural Resources
(IDNR) issued a permit to White-New Idea for an industrial solid
waste landfill. This landfill is currently under construction,
and should begin operation in January of 1991. At that time
disposal of solid wastes at the White Farm site will cease in
favor of the new landfill.
Between April 1989 and June 1990, a Remedial Investigation
(RI), Feasibility Study (FS), and Risk Assessment were conducted
for the site. EPA required the RIIFS in order to identify the
nature and extent of contamination at the site and to develop
ways of addressing contamination. The RIIFS work was conducted
by Allied Products Corporation, with EPA oversight, under the
terms of an Administrative Order on Consent issued by EPA
pursuant to Sections 104 and 122 of CERCLA, 42 U.S.C. SS 9604 and
9622. Following completion of the RIIFS, EPA prepared a Focused
Feasibility study in order to fill in a number of information
gaps. In July 1990, the RIIFS report, the Focused Feasibili~y
Study and BPAI. Proposed Plan for remedial action were released
to the public.
3.
Community Relations Activities
A Community Relations Plan for the .ite has been prepared
which lists contacts and interested parties in local government
and the community. It also establishes .ean8 of communication to
ensure timely dissemination of pertinent information to the
public. A fact sheet, the RIIFS, the Focused Feasibility Study,
and the Proposed Plan were released to the public on July 8,
1990. These documents were made available in both the
administrative record and the information repository located at
the Charles City Public Library. A notice of availability of
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4
these documents was placed in the Charles City Global Gazzette
and the Mason City Press on July 8, 1990. A public comment
period was held from July 8, 1990, until September 6, 1990. In
addition, a public meeting was held on July 12, 1990. At this
meeting, representatives from EPA and IDNR presented the results
of the RI/FS and the preferred alternative identified in the
Proposed Plan for the site and answered questions about the
remedial alternatives under consideration. All comments which
were received by EPA prior to the end of the public comment
period, including those expressed verbally at the public meeting,
are addressed in the Responsiveness Summary which is included in
this Record of Decision.
4.
ScoDe ~ ~ gI ResDonse Actions
The response actions at the site will independently address
two contaminated media: groundwater and solid wastes/soil.
Based on available information, the solid waste materials found
on site are of low toxicity, low mobility, and do not
significantly leach into the underlying native soils or
groundwater. Thus, the objectives of the response action with
regard to solid wastes/contaminated soil are to prevent human
exposure via direct onsite contact with the wastes and
contaminated soil and to prevent offsite transport of
contaminated materials.
The objectives of the remedial action with respect to
groundwater are to prevent further migration of contaminated
groundwater and to reduce levels of contaminants in groundwater
below established health-based standards for drinking water.
These objectives have been established to ensure protection of
drinking water supplies.
By meeting the objectives set forth for solid wastes,
contaminated soils, and groundwater, the selected remedy will
address the principal threats to human health and the environment
posed by the site. This remedial action will constitute the
final response action for this site.
5.
Summa~ Qf IitA Characteristics
During the RI/FS, the site was characterized to determine
the principal threats at the aite. Heavy metal contamination in
landfill material, volatile organic contamination in onsite
groundwater, and transport of heavy metal contamination via
surface water run-off were identified as principal threats. EPA
concluded that lesser threats are posed by leaching of metal
contamination into groundwater. Transport of contaminants via
airborne particulates and leaching of contaminated groundwater
into the Cedar valley Bedrock Aquifer, which provides drinking
water to Charles City, pose minimal threats.
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5
Four borings were placed through the landfill material and
into the native 80il below (Figure 2). The landfill material
ranged in thickness from 15 feet at WFE-l to 22 feet at WFE-2.
Four to six samples were collected at different depths from each
boring. Of the 18 samples taken, only one contained lead above
500 parts per million (ppm). Five of the 18 samples contained
base neutral acids, three contained phenols, and one contained
methylene chloride. None of these organic contaminants were
present in significant concentrations. The range of
concentrations of metals and organic compounds found is shown in
Table 1. Based on knowledge of the materials going into the
landfill obtained from information request letters and EPA's RCRA
inspection, EPA believes that the waste is of a relatively
homogeneous nature. Specifically, EPA concludes that there is
little probability that hot spots containing markedly higher
concentrations of contaminants exist in the landfill material.
Seven subsequent samples taken from landfill material were
submitted for Extraction Procedure Toxicity (EP-Tox) analysis.
sample from location WFE-2 contained extractable quantities of
lead and cadmium. The extractable concentrations were 0.26 ppm
cadmium and 2.6 ppm lead.
A
These concentrations of extractable lead and cadmium are
below the regulatory requirements for classification as a
hazardous waste. None of the other samples contained detectable
concentrations of extractable metals. EPA concluded from this
test that contaminants in the landfill do not leach significantly
into infiltrating water under the conditions simulated in the
test.
Six oftsite surface soil samples were taken from areas
downgradient of the landfill and analyzed for metals. All six of
the samples contained metals concentrations typically found in
u.S. soils. Air monitoring at up and downwind locations did not
indicate any siqnificant transport of contaminants via airborne
particulates. EPA concluded that minimal offsite migration of
landfill aaterials bas occurred.
Ten ...ple. were taken from sediments and surface water
drainage paths (Table 2). These samples indicated movement of
contaminants along surface water drainage routes (Figure 2). The
offsite sediment .ample. did not contain more than 100 ppm lead.
EPA concluded that the potential exists for contaminants in the
landfill material to migrate offsite through surface water run-
off. .
Surface water from the wetland area south of the landfill
was unavailable for sampling-during the Remedial Investigation
due to low water level conditions. Two offsite surface water
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lo
000 O"j
o
CENIRAl RAILROAD
DO
WFE.tOA, t.~
D cr7 80 B OatARlES
WFE.'A.I8e+ WATER PlANT
d 0
Do
o
c=Jg B
~
..~t WE.
:..-....
.. .a. ..
.. . e.... ..- .
. .... .. . A. ..
.. ..a...
.. . ... ....
.. ..... ..
WR.~t
.
.
WR-I-t4
. ..
.. .
.." ..
..
.. ..
.
WR-"
~-&-
..
.
IM-.
lEGEI8
. ....... WeI-
. ......~.......
o ..... WeI
. ..... SaIl
o l8IIN...
. PwWaua w.II
+ ....... Well
. ......
- Sud8D8 Dnin8g8
I
I
APIII8ODM.
&DCA11OII OF
HYERS CREEK
..
..
..
..
..
..
..
~..
.. ~
..
..
...to
o~
lLOCA1ED
APII'ROIl 3DO"
WEST OF ROAD
..
..
t. . -1-
ICaE _FEET
...a: --
.
..
..
FIGURE 2
SURFACE WATER DRAINAGE PATTERNS
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TABLE 1
WHrTE FAAN EQUIPMENT snc
LANDAU. MATERIAL - SOIL BORING ANAL. YSiS RANGE
NATURAL
ABUNDANCE
COMPOUND WFE-1S WFE-2S WFE-3S WFE-4S IN U.S. SOILS'
~
Methylene Chloride ND ND - 1500 ND ND ---
Naphthalene ND - 1000 ND - 3700 ND - 3500 ND ---
Phenanthrene ND ND-830 ND-980 ND ---
Benzo(B)Fluoranthene NO NO ND - 680 ND ---
Benzo(K)Fluoranthene ND NO NO-680 NO ---
Benzo(A)Pyr.ne ND NO ND - 3600 ND ---
Pnenol ND - 710 NO ND - 930 ND ---
~
ArMnic <0.5 - 3.9 <0.5 - 12 <0.1 - 2.1 2.1 - 13 1-50
Barium <3.3 - 26 2.6 - 16 --- --- 100-3,000
Cadmium <0.33 - 8.9 <0.26 - 0.77 <0.5 <0.35 - 89 0.01 -0.70
Chromium 1.7-69 ".2 - 73 5 - 210 3.5 - 99 1-1,000
Copper 18 - 89 4 - 180 10 - 380 8.1 - 410 2-100
Lead 4.3 - 160 4.2 - 120 6 - 150 7.9 - 9700 2-200
Manganese 1 1 - 760 --- 86 - 2100 --- 20-3,000
Zinc 7.6-110 15 - 120 26 - 67 17-11000 10-300
Nickle --- 3.5 - 70 8-390 11 - 150 5-500
ND . Not Detected
8_uO . Not Available
"Ref.: Lindsay, W.L. (1979). Chemical Equilibria in Soils, Wiley & Sons,
New York, p. 449
"
~IC: 1DVoI4FNU. W<1
. .. . ~ ." -. .
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TABLE 2
WHnE FA'" EQUIPMENT SITE
SEDIMENT SAMPLE ANALYSIS SUMMARY 1989
/
. ./ ~m)
NATURAL
ABUNDANCE
COMPOUND WFE-S-1 WFE-S-2 WFE-S-3 WFE-S-4 WFE-S-5 WFE-S-6 WFE-S-7 WFE-S-B WFE-S-9 WFE-S-10 IN U.S. SOILS.
ArsenIC 1.50 7.4 1.9 2.5 2.4 2.20 3.1 5.5 4.1 1.4 1 - 50
Barium 34.00 95.0 62.0 37.0 210.0 28.00 82.0 130.0 180.0 20.0 100 - 3.000
Cadmium 0.98 2.7 1.4 2.2 10.0 0.74 1.4 1.3 1.8 0.3 0.01 - 0.70
Chromium. Hexavalent <1.20 <1.2 <1.2 <1.2 <1.2 <1.20 <1.2 <1.2 <1.2 <1.2 . ---
Chromium. Tolal 2.40 9.9 25.0 9.2 8.8 6.20 7.8 11.0 3.8 1.2 1-1,000
Copper 12.00 38.0 38.0 17.0 42.0 8.80 22.0 19.0 5.2 1.5 2-100
Lead 57.00 210.0 98.0 230.0 910.0 44.00 89.0 75.0 27.0 7.5 2-200
Manganese 360.00 1100.0 960.0 520.0 2300.0 86.00 170.0 160.0 1100.0 130.0 20 - 3.000
Zinc 170.00 70.0 230.0 460.8 1800.0 140.00 110.0 140.0 27.0 14.0 10 - 300
. Ref.: Lindsay, W.l. (1979). ChemICal Equilibria In SoIls, Wiley & Sons,
New York, p.449
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9
samples were collected from Hyers Creek and showed slightly
elevated levels of metals. Metals concentrations in the Hyers
Creek samples did not exceed water quality criteria. EPA
concluded that no current risk exists to the sensitive wetland
environment adjacent to the site.
Groundwater .amples were collected from 16 monitoring wells
and analyzed for selected indicator compounds. The results
indicated the presence of the organic contaminants benzene
(25 ppb), ethylbenzene (44.8 ppb), toluene (72.4 ppb), and total
xylenes (394 ppb) in the groundwater at one location in the upper
aquifer in the landfill. Elevated concentrations of several
indicator metals were also found in wells located in the upper
aquifer beneath the landfill and downgradient of the landfill
(Table 3). None of the metals concentrations exceeded the MCLs
set by the Safe Drinking Water Act or groundwater cleanup levels
based on Iowa Administrative Code 5133.2 (455B, 455E). Analysis
of samples did not indicate contamination in the lower confined
aquifer. The results indicate that so far landfill contaminants
are not leaching to the groundwater or moving with groundwater
offsite to any appreciable extent.
The volatil9 organic compounds found in WFE-l were not
detected in any other well. These compounds were not detected in
any of the landfill material.
The compounds were found at a very low level in a localized
region. In addition, the presence of a non-aqueous phase liquid
source was not detected. Based on this information, EPA .
concluded that the volatile organic plume is a localized
phenomena.
,
A pum~ test performed on the aquifer shows that the clay
till layer that exists between the upper unconfined aquifer and
the lower confined Cedar valley aquifer, which Charles City uses
as a source of drinking water, acts as a barrier between the two
aquifers. The upper aquifer flows to the west/southwest, away
from the Charle. City municipal wells. The lower confined Cedar
Valley aquifer i. believed to flow to the northwest, but the
existing data 1. inconclusive (Figure 3). EPA concluded that the
two aquifer. 40 not intermix.
6.
SU1II1IIarv .Q! ~ Risks
During the RIfFS, an assessment was conducted to estimate
the health and environmental risks associated with the site. '
This analysis, or baseline risk assessment, concentrated on the
health effect. of ..tal and organic constituents in the landfill
material and groundwater. The supplemental risk calculations in
EPA's Focused Feasibility Study provide the basis for this
analysis. This document is contained in the administrative
record for this site.
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'.: .'.8 - NONFW.. TEMD fD88I.
,','..:Jfft
".IJ'
. .
I '.~"''''''
,....,.. TD181
0'"
....
....-
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9""
od
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on"""
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~-
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'JEJNEUffW. 0AIW8C8"",
......-
-......
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.....,..........
............
,.... .,.....
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TABLE 3
WHITE FARM EOUIPMENt SITE
GROUNDWATER SAMPlE ANAlYSIS SUMMARY 1989
VW'E-1 VW'E-2 VW'E-a WF£~ VW'E-18 WIFE"'" WFE.... WFE-a WFE-7. WFE-" WFE"'" WFE-a WIFE.... WFE"" 1WF£-101 WFE-111t MCl
-- 11M - . . 101 171 nil 17 27 '" 1711 27 .. . 17110 - I ..
.
-------
c
o
DD
WFE-10A, 108 ~
D Cf7 .0 B 0 atARlES
~~~.+ WAnR~Nn
IIMJIOAD
~
o
c::J g B
.
WR-..
6
~-S-1.
.
WFE-U
IIEIIDEImAL
WELl
---
WFE-S-1:1
..
80 I
WR-a I WFE-3 eo WFE-S-4 \
~ I -I-S-1S
WFE-S-3
.
I WfE-t1.
A'y~
.
IM-A
.
.. ~-~1 ...u.p
.......*.-
.. ..
WFE-4A,- . 1.
..
..
d 0
DO
WFE-~
..
WFE.7 7
1IW-2 G
lEOEJ8)
. ........ WII
. SecfIR8nI ~ l.ac88Iaft
o Sud8a8 WII
.. Sud8a8 Sell
o l8IdIiII""
. '-iau8W111
.. ....... Well
... w.c....
---+ MM81~Fbr
- . BedrodI AAPet Fbr
FIGURE 3
GROUNDWATER FLOW PATTERNS
~"'1E
lOCA1IOM OF
HYERS CREEl(
..
..
..
..
..
..
o
1 WfE-W-11A
LOCAtED APPRO" :lOG'
WEST OF ROAD
.
....z--
I
lell . 81C1O
SCALE" REf
.S-10
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12
Two contaminants of concern were identified in the Remedial
Investigation. Benzene was found in monitoring well WFE-l at a
concentration of 25 ppb. This exceeds the MCL for benzene of
5 ppb established pursuant to the Safe Drinking Water Act. The
action level for benzene in qroundwater established by Iowa
Administrative Code 5133.2 (455B, 455E) is 1 ppb. Benzene was
not detected in any other monitoring well during the RIfFS.
Lead was found in sediments and throughout the landfill
materials at concentrations of up to 230 ppm. One sample of
landfill material contained 9700 ppm lead. Lead typically occurs
naturally in U. S. soils at concentrations as high as 200 ppm.
The Risk Assessment identified two exposure pathways that
potentially pose unacceptable risks. Ingestion of contaminated
groundwater could result in risks associated with exposure to
benzene. Direct contact with the landfill material could result
in exposure to lead above health based levels.
Additional exposure pathways were examined and found to pose
acceptable risks. Specifically, air monitoring and downwind s~il
sampling indicated that significant offsite contaminant transport
via blowing dust has not occurred. Offsite soils and sediments
contained only low levels of lead (below 230 ppm). At this
concentration, based on current information, no heightened
potential for adverse health effects is expected.
Onsite workers, residential adults and children were
identified as potentially exposed populations. Residents (both
adults and children) onsite may be potentially exposed to lead
via direct contact and incidental ingestion of soils and to
benzene through ingestion of groundwater from a shallow drinking
water well. ,
"
The maximum concentrations found in both the landfill
material and groundwater were used as reasonable maximum exposure
point concentrations. standard exposure frequency assumptions
were used. This information is detailed in the Focused
Feasibili~y Study. For the residential scenario, a 70 year
exposure tor 365 days per year was assumed. For the worker
scenario, . 20 year exposure for 250 days per year was assumed.
Cancer potency factors (CPFs) have been developed by EPAls
Carcinogenic Assessment Group for estimating excess lifetime
cancer risks associated with exposure to potentially carcinoge~ic
chemicals. CPFs, which are expressed in units of (mg/kg-day)- ,
are multiplied by the estimated intake of a potential carcinogen,
in mg/kg-day, to provide an upper-bound estimate of excess
lifetime cancer risk associated with exposure at that intake
level. The term .upper bound" reflects the conservative estimate
of the risks calculated from the CPF. Use of this approach makes
underestimation of the actual cancer risk highly unlikely.
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13
Cancer potency factors are derived from the results of human
epidemiological studies or chronic animal bioassays to which
animal-to-human extrapolation and uncertainty factors have been
applied.
Excess lifetime cancer risks are determined by multiplying
the intake level with the CPF. These risks are probabilities
that a~g generally expressed in scientific notation 19.9. 1E-6 or
1 x 10 ). An excess lifetime cancer risk of 1 x 10 indicates
that as a plausible upper bound, an individual has a one in one
million chance of developing cancer a& a result of site-related
exposure to a carcinogen over a 70-year lifetime under the
specific exposure conditions at the site.
Ri~kS associated with contaminated groundwater exceed the
1 x 10- excess cancer risk used as a point of departure for
determining remediation goals as specified in the NCP, 40 C.F.R.
5300.430 (e) (2) (i) (A) (2). Benzene is a Class A human carcinogen,
which means that there is sufficient evidence from human
epidemiological studies to determine that the chemical is
carcinogenic in humans. The CPF for benzene is 2.9 x 10-2.
Benzene in the groundwater at the White F~rm Site results in an
excess lifetime cancer risk of 4.53 x 10- for children
(Table 4).
Contaminants found within the landfill materials do not
pose significant c~rcinogenic risks. Arsenic had the greatest
risk at 1.79 x 10-. No other compounds found in the landfill
materi~g result in an excess lifetime cancer risk greater than
1 x 10 .
Reference doses (RfDs) have been developed by EPA for
indicating the potential for adverse health effects from exposure
to chemicais exhibiting noncarcinogenic effects. RfDs, which are
expressed in units of mg/kg-day, are estimates of lifetime daily
exposure levels for humans, including sensitive individuals.
Estimated intakes of chemicals from environmental media (e.g.(
the amount of a chemical ingested from contaminated drinking
water) can be compared to the RfD. RfDs are derived from human
epidemiological 8tudie& or animal studies to which uncertainty
factors have been applied (8.g., to account for the use of animal
data to predict effects on humans). These uncertainty factors
help ensure that the RfDs will not underestimate the potential
for adverse noncarcinogenic effects to occur.
Potential concern for noncarcinogenic effects of a single
contaminant in a single medium is expressed as the hazard
quotient (or the ratio of the estimated intake derived from the
contaminant concentration in a given medium to the contaminant's
reference dose). By adding the hazard quotients for all
contaminants within a medium or across all media to which a given
population may reasonably be exposed, the Hazard Index (HI) can
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TABLE 4
BASELINE RJSKS SUMMARY
GROUNDWATER
Quantified Risk - Intake x Chemical-Specific PoteDCY Factor
Intake (mg/ka-day) - CW x IR x EF x ED
BW x AT
Where:
CoDtammant of CoDcem:
cw -
IR-
EF-
ED-
BW -
AT -
Chemical CODceDtraboD in waler (mg/1)
IDgcstjOD rate (liters/day)
EIposurc &cqUCDCY (day /ycv)
EIposure duration ()urs)
Body weight (kg)
A~asiDg time (days over 70 ycv lifetime)
BeDZ.Cne
Intake (m,lk,-dav) PoteDC;Y Fador .BiH
Residential Child: 1.56 x 10"3 2.9 x 10-2 4.53 x 10-5
Residential Adult 7.14 x 10-4 2.09 x 10-2 2.07 x 10.5
Hazard Index =
Intake (mg/kg-day) -
Where:
-,CS -
!R-
cr-
FI -
EF-
m-
aw .
AT.
"
(:ofttami"."t of Caacera:
.sWJ..
Intake
Chemical-Specific Refc:rC:Dce Dose:
CS x IR x CF x FI x EF x ED
BW x AT
Chemica! coDcentratiOD in soil (mg/kg)
InacstiOD rate (mg/day)
CoDversiOD factor (10-6 q/mg)
FractiOD iDgctsted &om CODtamiDated source (UDitless)
&posurc &cqueDCY (day/year)
EIposurc duratioD (years)
Body wei&bt (kg)
AverqiDa time (days over 70 year lifetime)
Lead
Intake lmflb-dav) RefereDce Dose HUJllrd IDdex
RcsideDtial Child: 1.21 x 10-1 1.4 x 10-3 86.6
RcsideDtial Adult: 1.39 x 10-2 1.4 x 10-3 9.89
Onsi1e Worker: 9.49 x 10"3 1.4 x 10-3 6.8
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15
be generated. The HI provides a useful reference point for
gauging the potential significance of multiple contaminant
exposures within a single medium or across media.
Risks associated with exposure to lead contamination in the
landfill material exceed acceptable exposure levels as specified
in the NCP, 40 C.F.R. 5300.430 (e)(2)(i)(A)(1). Lead exhibits
non-carcinogenic health effects, and is described in terms of a
reference dose. The reference dose for lead is 1.4 x 10-3. This
results in HIs of 86.6 for residential children, 9.89 for
residential adults, and 6.8 for onsite workers.
None of the compounds in groundwater resulted in a hazard
index greater than 1. Manganese resulted in a HI of 0.91, the
highest for exposure to groundwater by residential children.
The Agency for Toxic Substances and Disease Registry (ATSDR)
has conducted a preliminary draft Health Assessment for this site
which is available in the administrative record. The report
concludes that the site poses risks to human health caused by the
possibility of exposure to hazardous substances via ingestion and
inhalation of contaminated groundwater, surface water and onsite
soils. ATSDR has reviewed the RI/FS, Risk Assessment, and EPA's
Focused Feasibility Study, and finds the selected remedy to be
adequately protective of human health.
The EPA has determined that the cleanup goals for
groundwater at the site will consist of the lower of MCLs or
groundwater action levels based on Iowa Administrative Code
5133.2 (455B, 455E). Since no state or federal cleanup levels
have been set for soils, EPA has targeted cleanup of soils to an
exposure level below the RfD based on direct contact and
ingestion." This cleanup target was established for this site as
part of the risk assessment conducted during the RIfFS.
Although offsite concentrations of lead in surface water
drainage paths do not indicate any current threats to human
health or the environment (Table 2), they do demonstrate that
offsite tranaport via run-off i. occurring. Continued run-off
poses potential future risks to the sensitive wetland environment
adjacent to the .ite.
Actual or threatened releases of hazardous substances from
this site, if not addressed by the selected remedy identified in
this ROD, aay pre.ent.a sub.tantial endangerment to public health
or the environment.
7.
DescriDtion 21 Alternatives
A wide range of remedial technologies for both groundwater
and contaminated wastes/soils were initially screened based on
effectiveness, implementability and cost. Based on this initia:
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16
screeninq, five remedial alternatives were retained and evaluated
in detail.
These remedial alternatives were evaluated to determine how
well each addressed the three principal threats posed by the
site: the localized plume of shallow alluvial groundwater
contaminated with 25 ppb of benzene; the 650,000 cubic yards of
landfill material with lead concentrations as hiqh as 9700 ppm;
and the potential transport of lead contamination into the
wetland areas via 8urface vater run-off. Followinq is a
description of the remedial alternatives that were retained:
. Alternative 1.
. Alternative 2.
. Alternative 3.
.
Alternative 5.
No Action;
Fencinq , Monitorinq;
Surface Controls, Cappinq
, Groundwater Extraction and Treatment;
Excavation and Offsite Disposal
with Groundwater Extraction and Treatment; and
Excavation and Onsite Treatment
with Groundwater Extraction and Treatment
. Alternative 4.
Alternative 1:
BO ACTION
The National Oil and Hazardous Substances Pollution .
continqency Plan (NCP), 40 C.F.R. Part 300, requires evaluation
of the no action alternative in order to provide a baseline of
comparison for the other alternatives. The no action alternative
would allow site conditions to remain as they currently exist.
This action would result in an excess cancer risk level of
4.5 x 10-5. The HIs would remain at 86.6, 9.89, and 6.8 for
residential children, adults and workers respectively (Table 5).
The ~ action alternative could be implemented immediately,
since no action vould be taken. There are no costs associated
with this alternative.
Alternative 21
."CIBG , MOBI'1'ORIBG
Alternative 2 utilizes institutional controls to minimize
the impact of contaminated landfill material and groundwater.
This alternative does not aitiqate offsite transport via surface
water run-off.
The principal elements ot Alternative 2 include: fencinq
the perimeter of the 8ite to restrict acceS8 to the landfill
material, employinq deed restrictions to limit future property
use and vell installation, a lonq-term qroundwater monitorinq
program, and a lonq-term fence inspection and maintenance
proqram.
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TABLE 5
RISK EVALUATION
FOR
PROPOSED REMEDIAL ALTERNATIVES
/
/
GROUNDWATER SOIL
ALTERNATIVE ResIdential Child Residential Child Residential Aduh On-Slte Worker
-5
Alternative 1 4.53 x 10 Cardnogenlc Risk 86.6 Hazard Index 9.89 Hazard Index 8.8 Hazard Index
-5
Ahernatlve 2 4.53 x 10 Cardnogenlc Risk 7.12 Hazard Index 0.8 Hazard Index 8.8 Hazard Index
-6
Alternative 3 1.81 x 10 Cardnogenlc Risk 0.9 Hazard Index 0.4 Hazard Index 0.8 Hazard Index
-6
Alternative 4 1.81'x 10 Cardnogenlc Risk 0.09 Hazard Index 0.01 Hazard Index 0.01 Hazard Index
-6
Ahernatlve 5 1.81 x 10 Cardnogenlc Risk 0.09 Hazard Index 0.01 Hazard Index 0.01 Hazard Index
Groundwater Contaminant 0' Concern: Benzene
Soli Contaminant of Concern: Lead
Alternative 1 - No Action
Alternative 2 - Fencing and Monitoring
Alternative 3 - Capping and SoIl Cover and Groundwater Treatment
Alternative 4 - Excavation. Off-Site Disposal and Groundwater Treatment
Alternative 5 - Excavation. On-Site Treatment and Groundwater Monitoring
JEMC:IlOTUSlTlllOTH
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18
Because this alternative would result in contaminants
remaining onsite, CERCLA requires that the site be reviewed every
five years. If justified by the review, remedial actions would
be implemented at that time to remove or treat the wastes.
This5alternative results in a residual cancer risk of
4.5 x 10- and a HI of 7.12. These risk factors are based on
decreased exposure to contaminated landfill material by
residential children (Table 5).
This remedy would require approximately three months to
implement. The associated costs include $75,100 capital costs
and $5,500 yearly operating and maintenance costs for 30 years.
This corresponds to a net present value of $159,646 (Table 6).
Alternative 3:
8URPACE CONTROLS, CAPPING
, GROUNDWATER BZTRACTION AND TREATKENT
Alternative 3 utilizes treatment to mitigate risks
associated with contaminated groundwater. Containment measures
mitigate risks from landfill material and surface water run-off
and institutional controls provide additional protection.
Alternative 3 includes the fencing, deed restrictions, and
long-term monitoring described under Alternative 2. In addition,
this alternative includes regrading the landfill to control
surface water run-off and erosion and installing a cover on the
landfill materials. The cover would prevent direct contact with
the landfill materials, reduce infiltration and leaching of
contaminants by covering the site with an impermeable layer, and
minimize run-off transport of contaminants. The cover would
consist of low permeability compacted soil covered with
uncompactedsoil, or alternate materials providing equal or
superior performance. The covered areas would be revegetated to
further control surface run-off and erosion. A cover maintenance
and inspection program would be implemented to replace soil and
vegetation lost to erosion. Adjacent wetlands would be protected
from landfill aaterials by the reduction in contaminant run-off
provided by the cover. This alternative would comply with state
of Iowa requirements for closure of solid waste landfills which
are contained at Section 567-103.2(13) of the Iowa Administrative
Code. .
The cover, fence and groundwater treatment system will be
designed, constructed and implemented in a manner that will
minimize impacta on the adjacent wetlands to the maximum extent
practical. Specifically the remedy will minimize release of
hazardous substances into the wetlands, movement of equipment and
materials through the wetlands, and actions that could affect the
sensitive environment.
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19
This alternative also adds qroundwater extraction and
treatment to the fencing and monitoring elements of
Alternative 2. Groundwater extraction and treatment would
require the installation of additional monitoring wells and
collection of analytical data in order to effectively locate
qroundwater extraction welles). Extraction welles) would then be
installed and operated to effectively capture all the
contaminated qroundwater at the site. Treatment/removal of
contaminants from the qroundwater would be achieved by air
stripping. Groundwater extraction and treatment will continue
until the qroundwater action levels established by Section 133.2
(455B, 455E) of the Iowa Administrative Code are achieved and
maintained throughout the site. This will take approximately
five years.
Although data from the RI/FS indicates that groundwater at
the site is not contaminated by metals at levels exceeding State
of Iowa groundwater action levels, it is possible that the
remedial design investigations may find groundwater contaminated
with metals at concentrations exceeding action levels. If this
is the case, additional extraction and treatment would be
provided as necessary to restore groundwater to the action levels
set forth by Iowa law.
Depending upon the volume of groundwater which is extracted,
treated groundwater may be discharged directly to Hyers Creek via
a ditch, channel, pipe, storm sewer, or other means, or may be
used for irrigation in establishing a vegetative cover on the
landfill and ultimately discharged to Hyers Creek. Either
discharge would be considered a direct discharge to surface
waters and would require an NPDES permit from the State of Iowa.
The u~e of an air stripper to remove volatile organic
compounds from qroundwater causes contaminants to be transformed
from a liquid phase to a vapor phase and subsequently released to
the ambient air. Air emissions resulting from operation of an
air stripper .hall comply with the requirements of 40 C.F.R. 5264
Subpart AA and SS.
If groundwater treatment requires carbon adsorption for
control of air emissions, spent carbon will be disposed of or
recycled at a RCRA-approved facility in accordance with EPA
policy on offsite disposal of CERCLA waste.
Because this alternative would result in contaminants
remaining onsite, CERCLA require. that the site be reviewed every
five years. If justified by.the review, remedial actions would
be implemented at that time to remove or treat the wastes.
This tlternative results in a residual cancer risk of
1.81 x 10- for groundwater and a hazard index of 0.9 for
landfill material. These risk factors are based on a reduction
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20
of benzene concentrations in groundwater and decreased exposure
of residential children to the contaminated landfill material
through the containment action of the cap.
Alternative 3 would require approximately 6 months to
implement. Costs associated with this alternative include
$1,569,291 in capital costs and $89,345 annual operating and
maintenance costs. This results in a net present value cost of
$2,352,121.
Alternative 4: EXCAVATION, O778ITE DISPOSAL
i GROUNDWATER EXTRACTION AND TREATMENT
Alternative 4 utilizes treatment to mitigate risks
associated with contaminated groundvater. Risks from landfill
materials and surface water run-off would be eliminated by
removal of the landfill material.
Alternative 4 includes the excavation and physical removal
of all hazardous substances from the site. Under this
alternative, landfill materials and soils containing hazardous
substances would be excavated, loaded onto trucks, and hauled to
an approved offsite RCRA landfill for disposal. The excavations
would be backfilled with clean fill material, covered with a
layer of topsoil, and revegetated. The excavation plan woulc
designed to minimize the release or contaminants during the
removal of landfill materials. This remedy would be a permanent
measure and would eliminate the need for site maintenance, access
restrictions, and deed restrictions.
The landfill excavation and groundwater extraction and
treatment system would be designed, constructed and implemented
in a manner that would minimize impacts on the adjacent wetlands
to the maximum extent practical. Specifically, the remedy would
minimize, to the maximum extent practical, release of hazardous
substances into the wetlands, movement of equipment and materials
through the wetlands, and actions that could effect the sensitive
environment.
This alternative would also include groundwater extraction
and treatment and long-term monitoring as described for
Alternative 3.
Because this alternative would result in contaminants
remaining onsite, CERCLA requires that the site be reviewed every
five years. If justified by the review, remedial actions would
be implemented at that time to remove or treat the wastes.
This alternative results in a residual cancer risk of
1.81 x 10"6 for groundwater and a HI of 0.09 for landfill
material. These risk factors are based on a reduction of te-:••-•
concentrations in groundwater and removal of the lead conta.- ;
landfill material.
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21
This alternative would require approximately three months to
implement. The associated costs are $148,069,300 in capital
costs, and $53,400 in annual operating and maintenance costs.
This results in net present value of $148,531,048.
Alternative Sa
8ZCAnTIOH, OHSITB ftDTIUDI'T
, cmoOlfDnTD Bn'ItACTIOH AND TRDTKDIT
Alternative 5 utilizes treatment to mitigate all risks posed
by the site. The alternative also includes institutional and
containment measures to provide further protection.
This alternative includes excavation of the approximately
650,000 cubic yards of landfill material coupled with onsite
treatment. Treatment of landfill material would consist of
fixation or stabilization of heavy metal contamination through
use of a cement agent to decrease the leaching of heavy metals to
the groundwater. Treated stabilized soil would be redeposited in
the excavation, covered with clay and clean soil, and revegetated
as described under Alternative 3. This would reduce the
likelihood of direct contact, reduce the possibility of
contaminants leaching to groundwater, and minimize offsite
migration through erosion and wind dispersion.
The landfill excavation and treatment and the groundwater
treatment systems will be designed, constructed and implemented
in a manner that will minimize impacts on the adjacent wetlands
to the maximum extent practical. Specifically, the remedy would
minimize to the maximum extent practical release of hazardous
substances into the wetlands, movement of equipment and materials
through the wetlands, and actions that could effect the sensitive
environment.
"
This alternative would also include groundwater extraction
and treatment and long-term monitoring a. described for
Alternative 3. Becauae the fixated or atabilized waste would
remain on.it. under this alternative, deed and access
restrictioft8 would also be included as part of this alternative.
Becaua. this alternative would result in contaminants
remaining on.it., CERCLA requires that the site be reviewed every
five years. If justified by the review, remedial actions would
be implemented at that time to remove or treat the wastes.
This tlternative result. in a residual cancer risk of
1.81 x 10- for groundwater and a HI of 0.09 for landfill
material. The.e ri.k factors are based on the reduction of
benzene concentrations in groundwater and decreased exposure
through treatment and containment of lead containing landfill
material.
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22
This alternative could be implemented in 7 months.
costs include $15,969,291 in capital costs, and $89,345
operating and maintenance costs. This results in a net
value of $16,752,121.
The
yearly in
present
8.
SummarY 2f ComDarative Analvsis 2f Alternatives
A detailed analysis was performed on the five alternatives
using nine evaluation criteria in order to select a site remedy.
The following is a summary of the comparison of each
alternative's strength and weakness with respect to the nine
evaluation criteria. The nine criteria are: 1) overall
protection of human health and the environment, 2) compliance
with applicable or relevant and appropriate requirements (ARARs),
3) short-term effectiveness, 4) long-term effectiveness and
permanence, 5) cost, 6) reduction of toxicity, mobility and
volume, 7) implementability, 8) state acceptance, and
9) community acceptance. This analysis is summarized in Table 6.
The threshold criteria are overall protection and compliance
with ARARS. Both of these criteria must be met by any selected
remedy.
A.
Overall Protection
Evaluation of the overall protectiveness of each alternative
focuses on how the alternative achieves protection over time and
how the risks are eliminated, reduced and controlled. The
selected remedy must be protective of human health and the
environment.
Alter~atives 3, 4 and 5 would all be protective of human
health and the environment by eliminating, reducing, or
controlling risks through various combinations of treatment and
engineering and/or institutional controls. All three of these
alternative. reduce the risks associated with exposure to
contaminated groundwater by pumpinq and treatinq contaminated
groundwater.
With regard to the landfill materials, Alternative 4
provides adequate protection of human health and the environment
by the excavaton and offsite disposal of the hazardous
constituents in the solid wastes and contaminated soils and
therefore reduces the risks associated with direct exposure to
the landfill materials.
Alternative 5 is protective because it includes physical and
chemical treatment of the hazardous constituents in the landfill
material.
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TABLE 6
ANALYSES OF Al TERNA11VES AGAINST
EVALUATION CRrrERIA
THRESHOlD CRITERIA BALANCING CRITERIA
PrOCectlve of Meets long-Term Reduction In Short- Term Implementability Costs
Hum8n Health ARARs E"ectlveness Toxicity, Mobility Elfectlveness (DIscount rate was
Ind Envtronment and Permanence and Volume assumed to be 5"')
/
Attematlw8 1 NO NO Non. None No potential Technically Ind None
Short-term Impacts Administratively
Implementlble
Attematlw8 2 NO NO Non. Non. No potential Technically and Capital: 175,100
Short-term Impacts Administratively 0 & M: 15,500
Imptementable Nil Preeent Value: $159,646
Altematlw8 3 YES YES V.., high lor High reduction In Slight potential Technicafty and CapItal: ",569.29'
groundwater. Good mobility and volume Impact on human Administratively 0 & M: $89,345
for IIndfll 01 ground water health and ImpIement.1e Net Present Value: $2,352,121
mat"'" but contamination. High wetlands during
d8pendent on reduction In mobllily regrading
maintenance of cap. ollaOOl1ll materials.
Alternative 4 YES YES V.., high lor both High reduction In Potentlallmpact Technlclllyand Capltll: "48,069,300
landlll materials and mobility and volume on human health Administratively 0 & M: 153,400 - 5 years
ground water. of ground ..ter and wetlands 1mpIement8ble "5,000 - 30 years
contamination. High during excavation Net Present Value: $148.531.048
reduction In mobility
oliandlill materials.
Alternative 5 YES YES V.., high lor High reduction In Pocentlallmpact Technlcllly and Capital: '15.969.291
groundwater. High mobility and volume on human health Administratively 0 & M: $89,345
lor landll. 01 ground water and wetlands ImpJernentabie Net Present Value: $16,752,121
materials. contamination. High during excavation
reduction In mobility
01 landfill materials.
.If' ,IC:LOTUSI-0726
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24
Alternative 3 includes access restrictions, institutional
controls, surface controls, and capping, which would effectively
protect human health and the environment by preventing direct
exposure to contaminated soils and wastes and reducing offsite
contaminant transport via wind and surface run-off. ~hese
measures will also limit. precipitation infiltration through the
landfill material and thus prevent leaching of contaminants into
groundwater.
Alternative 2 provides limited protection, as it does not
include any measures to prevent contaminants onsite in the
landfill from moving offsite via wind and surface run-off.
Alternative 2 does not include groundwater treatment, but would
provide limited protection from exposure to contaminated
groundwater through institutional controls and groundwater
monitoring.
Alternative 1, the no action alternative, is not protective
of human health and the environment.
B.
ComDliance ~ ARARs
Section 121 (d) of CERCLA, as amended by SARA, requires that
remedial actions comply with ARARs under federal and state
environmental laws. The selected remedy must comply with the
ARARs or justification for a waiver must be provided.
Alternatives 3, 4 and 5 would comply with all ARARs that
have been identified. Specifically, groundwater extraction and
treatment will continue until the action levels established by
Section 133.2 (455B, 455E) of the Iowa Administrative Code have
been attained. When extraction and treatment is discontinued,
long-term monitoring would be employed under these alternatives
to ensure'''that contaminant concentrations remain at or below
action levels.
Treated groundwater discharged to Hyers Creek or site run-
off channeled directly to Hyers Creek will require an NPDES'
permi t froa the state of Iowa.
Air .tripping operations to remove volatile organic
compounds from groundwater will comply with the requirements of
40 CFR 5264 Subpart AA and BB. If carbon adsorption is used to
control air emissions, spent carbon would be disposed of in
accordance with the requirements of RCRA Subtitle C, including
RCRA Land Disposal Restrictions (LORs).
Alternatives 4 and 5 would both involve placement of wastes.
At this time, the wastes are neither listed or characteristic
RCRA wastes, and thus RCRA Subtitle C requirements are not
applicable. In addition, since the data indicate that there are
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25
only low concentrations of hazardous constituents dispersed over
a wide area, RCRA Subtitle C provisions are not relevant and
appropriate elements of this remedial action involving the
landfill materials. However, effective September 1990, the
Toxicity Characteristic Leachate Procedure will replace the
EP-Tox analysis that was used to classify landfill materials at
the site a8 non-RCRA wastes. If landfill materials fail the new
TCLP tests, these alternatives would need to meet the RCRA LDR
requirements.
Capping and surface controls included in Alternative 3 do
not constitute placement of a hazardous waste, and thus the LDRs
are not ARARs for Alternative 3. The clay and soil cover, slope
regrading and vegetative cover, and long-term monitoring included
in Alternative 3 will meet the requirements of the 567 I.A.C.
5103.2(13), which contains regulations governing closure of solid
waste landfills. Alternatives 4 and 5 would also both meet the
o State of Iowa requlations governing the closure of solid waste
landfills.
Appendix A of 40 CFR Part 6 requires that federal actions
minimize adverse impact upon wetlands. All the remedies would be
designed and constructed in a manner which would minimize impacts
upon the wetland areas adjacent to the site. Also, the remedies
will be designed to minimize surface water drainage impact upon
wetland areas.
Alternatives 1 and 2 do not include treatment of
groundwater, and therefore do not meet ARARs since groundwater
contaminants which were detected above federal and state drinking
water standards would not be addressed by these options. These
alternatives do not meet threshold criteria and will not be
considered further in this analysis.
The five balancing criteria are used to compare the
alternatives that meet the threshold criteria against one
another. This balancing analysis results in selection of the
most cost-effective remedy.
C.
Lona-t8r8 Effectiveness An4 Permanence
Thi. evaluation focuses on the results of a remedial action
in terms of the ri.k remaining at the .ite after the response
objectives have been .et.
Alternatives 3, 4 and 5, which include groundwater
extraction and treatment, all provide effective and permanent
long-term .olutions for remediating contaminated groundwater. Ir.
addition, Alternatives 3 and 5 involve groundwater monitoring to
ensure over the long-term that contaminants are not entering the
groundwater. The difference between the alternatives with regarj
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26
to long-term effectiveness and permanence is directly related to
the manner in which each alternative addresses contaminated soi15
and wastes at the site.
Alternative 5 includes treatment of landfill materials by
soil stabilization, which would reduce contaminant migration and
provide a high degree of long-term effectiveness and permanence
with regard to the landfill contaminants. This alternative would
be the most effective in providing a long-term remedy with regard
to the landfill materials.
Alternative 3 would be effective in the long-term in
preventing direct contact with the contaminated landfill material
through use of fencing, deed restrictions, a cap, and a
vegetative cover.
Although Alternative 4, excavation and removal of the
landfill material, would also provide an effective long-term
remedy, CERCLA S 121(b)1 states that offsite transport and
disposal without treatment is the least preferred alternative
where practical treatment technologies are available.
D.
Reduction 2f Toxicitv. Mobilitv. QX Volume
This analysis addresses the statutory preference for
selecting remedial actions that employ treatment technologies
which permanently and significantly reduce toxicity, mobility, or
volume of the hazardous substances. This preference is satisfied
when treatment is used to reduce the principal threats at a site
through destruction of toxic contaminants, irreversible reduction
in contaminant mobility, or reduction of total volume of
contaminated media.
~
The groundwater extraction and treatment included in
Alternatives 3, 4 and 5 would greatly reduce the toxicity,
mobility and volume of contaminated groundwater by containment of
the plume and removal of contaminants from groundwater at the
site. The ditterence between the alternatives is in the
treatment ot contaminants present in soils and solid wastes at
the site.
Alternative 5, onsite treatment by atabilization, would
provide the greatest reduction in mobility of landfill materials,
but would not reduce their toxicity or volume. Alternative 4
would remove the toxic aaterials, reducing the toxicity and
volume of on.ite landfill material. Alternative 3 includes a cap
and a vegetative cover and thus would aiqnificantly reduce the
mobility of landfill materials by preventing erosion, wind
dispersal and infiltration through the landfill. Alternative 3
would not reduce the toxicity or volume of landfill materials.
-------
27
E.
Short-Term Effectiveness
This evaluation focuses on the effects on human health and
the environment which may occur while the alternative is being
implemented and until the remedial objectives are met.
All of the protective and ARAR-compliant alternatives, as
presented, would provide short-term effectiveness. All include
the use of access restrictions, which will almost immediately
achieve protection from direct contact with contaminants.
Fencing can be erected in approximately three months and deed
restrictions limiting future use of affected property and
limiting well development can be in place quickly.
Information available at the present time indicates that
qroundwater will need to be extracted and treated for
approximately five years in order to reduce contaminant levels
below the IGAL of 1 ppb of benzene. However, the volume of
contaminated groundwater will not be fully determined until
additional work is completed during remedial desiqn, and the
actual aquifer restoration time frame may vary.
Alternative 3 will result in minimal material disturbance
and should not adversely impact workers, the community, or the
environment. Cap installation would take approximately six
months to complete.
Noise and dust can be expected if onsite treatment is
implemented. Excavation and offsite removal of landfill
materials would result in fairly significant community
disturbance due to dust and traffic.
F.
Imnlementabilitv
This evaluation addresses the technical and administrative
feasibility of implementing the alternatives and the availability
of the various services and materials required during its
implementation.
All of the remedial alternatives are technically feasible
and routinely practiced. Alternative 4 would require permits for
removal of excavated landfill .aterials from the site. Discharge
permits for treated groundwater and compliance with state
regulations would be required before initiating site remediation
activities but are not anticipated to adversely affect the
implementability of the alternatives.
G.
~
This evaluation examines the estimated costs for
implementing the remedial alternatives. Capital and annual
-------
28
operating and maintenance costs are used to calculate estimated
present worth costs for each alternative. Alternative 3 is the
most cost-effective remedy based on the present worth analysis
(Table 6).
The final two criteria, state and community acceptance, are
referred to as modifying criteria. These criteria were
considered prior to and during the public comment period.
Following the public comment period, comments were addressed and
have been incorporated into this ROD.
H.
Community AcceDtance
Community response to the alternatives is presented in the
responsiveness summary which addresses comments received during
the public comment period.
I.
State Accectance
IDNR has reviewed and commented on the RIfFS documents and
the Proposed Plan. The State of Iowa concurs with the selected
remedy for this site.
9.
Selected Remedy
The selected remedy for the White Farm Equipment Company
Dump site is Alternative 3. EPA has established the following
remediation goals for this remedy.
The remediation goal for the landfill cover is to control
surface water run-off and infiltration to minimize impact to the
wetland areas, to mitigate direct contact and incidental
inqestiun of landfill materials, and to limit infiltration and
leaching of contaminants from the landfill material. This is to
be accomplished by a low permeability compacted clay layer
covered by soil sufficient to support vegetation, or alternative
materials providing equal or superior performance in compliance
with 567 I.A.C. 5103.2(13). The cover must be graded to provide
for adequate .urface water drainage, and must have a slope of
between 5' and 25' upon completion.
The 90al of the groundwater extraction and treatment is to
restore groundwater to its beneficial use throughout the site,
which i., at tbi. .ite, use as a potable water supply. The
specific remediation 90a1 for groundwater is to achieve and
maintain a benzene concentration of less than 1 ppb. Based on
information obtained during the remedial investigation and on a
careful analysis of all remedial alternatives, EPA believes that
the selected remedy will achieve this goal. It may become
apparent during implementation or operation of the groundwater
extraction and treatment system that contaminant levels have
-------
29
ceased to decline and are remaining constant at levels higher
than the remediation goals. In such a case, the system
performance standards and/or the remedy may be reevaluated.
The selected remedy consists of the follQwing:
.
Institutional controls including perimeter fencing and deed
restrictions on well installations and property use;
Engineering controls including regrading and covering the
landfill with an impermeable layer topsoil and vegetation to
reduce transport of contaminants through infiltration,
leaching, run-off and erosion;
.
.
Installation of additional groundwater monitoring wells and
collection of analytical data for design purposes;
Placement of extraction wells, a treatment facility (air
stripper), and discharge conveyance to Hyers Creek;
.
.
Extraction and treatment of contaminated groundwater until
the concentration of benzene in groundwater is reduced and
maintained helow I ppb;
.
Discharge of treated groundwater to Hyers Creek under an
NPDES permit;
Addition of a metals treatment train should monitoring
indicate that MCLs and IGALs for metals contaminants-are not
being met;
.
.
Inspection and maintenance of perimeter fencing, the landfill
cover.~nd vegetation, and the groundwater treatment facility;
and
Long-term groundwater monitoring.
.
The conceptual desiqn of the landfill cover is shown in
Fiqure 4. A potential groundwater treatment schematic is shown
in Fiqure 5. The actual de.iqn of these units .ay vary during
the remedial de.iqn. A detailed cost analysis for the selected
remedy is 9iven in Table 7.
The cover, fence and groundwater treatment system will be
desiqned, constructed and implemented in a ..nner that will
minimjze impacts on the adjacent wetlands to the aaximum extent
practical. specifically, the remedy will minimize release of
hazardous substances into the wetlands, movement of equipment and
materials through the wetlands, and actions that could effect the
sensitive wetland environment.
-------
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-------
FROM GROUNDWATER
EXTRACI10H WELL
GROUNDWATER
STORAGE TANK
"
"-LINE
DUCT
HEA\
CLEAN AIR TO
'A'fIIOSPHERE
/
VAPOR PHASE
ACT1VATED CARBON ADSORPTION
DISCHARGE UNDER A
NATIONAL POlLunoN
DISCHARGE
El",ATION SYSTEM
(NPDES) PERI1fT'
TO HYERS CREEK
AIR BLOWER
PACKED
AIR STRIPPER
FIGURES
ALTERNATIVE 3 - GROUNDWATER TREATllEHT
AIR STRIPPER SatEIIAnC
-------
TAILE 7
AI. 11:RNA11VI 3
COST BR£.&rnoWN
Capital Cost
o CappiDg aDd SoiJ CoYer
Regrading
SoiJ Colt (SUS/cy)
SoiJ TrIDSportatioa (S6/cy)
Equipment (SI680/day) (40 days)
R~OD (S900/acre)
OYa'bud aDd Fee
o
FeDc:mg
o
GrOUDdwater Treatment
4 mooitoriDg weDs, 4° diameter
30' deep at SBO/foot
1 production weD, 6° diameter
40' deep at S12O/foot
1 pump
Air Stripper with Carbon Absorptjon
EngiDeeriDg aDd Management
Contingency (10%)
Total ~pitaJ Cost
Operation aDd MalateD8DCe Coats (ADDu.1)
o
Capping and Soil CoYer (30 years)
Equipment (SI(o)/day) (5 days)
Soil (SI.2S/cy) (2000 cy)
TrIDSport (S6/cy) (2000 cy)
EqiDeeriDg aDd Management (740)
"
o
GroUDdwater (5 ~ treatment)
Elcctriciry (S4000/moath)
CarboD Reae.eraUo.
w~"riD& (1")
o
Quarterly Oroaadwater Moai1oriDg (30 yw'S)
Net Present Worth "_ala:
P . A (Q..t.j)u..:J]
Ii (l + i)8]
i . DiIcouDt Rate
D . Number of Years
P . Net Present Value
A . Cost
.
All calculations are made with . 5% discoUDt rite
P All 3 . $2,35%,1%1
:~: \ r::t. PJ~\D2l5\ nmt920.DOC
16,(0)
161.350
774,480
67)00
18,
367.861
$1.404,891
75,100
9,600
4,800
1,SOO
6O,
5,300
.a.w
SU69,291
5,(0)
2,SOO
12,
~
$20,865
48,(0)
1.
JSO
153,480
$15,(0)
-------
33
The selected remedy will include groundwater extraction and
treatment for an estimated period of five years, during which the
system's performance will be carefully monitored on a reqular
basis and adjusted as warranted by the performance data collected
during operation. The operating system may include discontinuing
operation of extraction welles) in areas where cleanup goals have
been attained, alternating pumping wells to eliminate stagnation
points, and pulse pumping to allow aquifer equilibration and
encourage adsorbed contaminants to partition into groundwater.
Treated groundwater will ultimately be discharged to Hyers
Creek under an NPDES permit issued by the State of Iowa. Prior
to discharge, the treated water may be used for irrigation of the
vegetative cover.
The use of an air stripper to remove volatile organic
compounds (VOCs) from groundwater causes the contaminants to be
transferred from a liquid phase to a vapor phase and are
subsequently released to the ambient air. A vapor phase carbon
adsorption unit shall be used if the air emissions from the air
stripper exceed the emission limit goals specified in 40 C.F.R.
264 Subpart AA and SUbpart BB.
If groundwater treatment requires carbon adsorption, spent
carbon will be disposed of or recycled at a RCRA-approved
facility.
10.
Statuto~v Determinations
Under its legal authority, EPA's primary responsibility at
Superfund sites is to undertake remedial action. that achieve
adequate protection of human health and the environment. In
addition, Section 121 ot CERCLA establishes .everal other
statutory requirements and preferences. These specity that when
complete, the selected remedial action for this site must comply
with applicable or relevant and appropriate environmental.
standards e.tablished under federal and .tate environmental laws,
unless a .tatutory waiver is justitied. The .elected remedy must
also be cost-ettective and utilize permanent .olutions and
alternative treataent technologies or resource recovery
technologies to the aaximum extent pos.ible. Finally, the
statute includes a preterence tor reaedies that employ treatment
that peraanently and signiticantly reduce. the volume, toxicity,
or mobility ot hazardous wastes as their principal element. The
following .ections discus. bow the .elected remedy meet. these
statutory requirement..
A.
Protection 2f Human Health ~ ~ Environment
The selected remedy protects human health and the
environment through extraction and treatment of contaminated
groundwater, tencing and deed restrictions, and capping the site.
-------
34
Extraction and treatment of contaminated groundwater will
eliminate the threat of exposure from ingestion of contaminate'
groundwater. The current risk associated with this exposure
pathway is 4.53 x 10~ . By reducing contaminant levels below •
action levels established by Section 133.1 of the Iowa
Administrative Code, the cancer risks from exposure will be
reduced to less than 1 x 10~6. Capping and fencing the landfi.
will reduce the risks of exposure due to direct contact with, <
ingestion of, contaminated wastes/soils. The current risk
associated with these exposure pathways is quantified by a HI <
86.6, and following implementation of the selected remedy thes<
risks will be reduced to a level corresponding to a HI of less
than one.
There are no short term threats associated with the remedy
that cannot be readily controlled. In addition, no adverse
cross-media impacts are expected from the remedy.
B. Attainment of Applicable or Relevant and Appropriate
Requirements of Environmental Laws
The selected remedy will comply with all applicable or
relevant and appropriate chemical-, action-, and location-
specific (ARARs). The ARARs are presented below.
Chemical-Specific ARARs
567 I.A.C. S133.2(455B,455E) specifies a hierarchy that is
to be used in establishing cleanup levels for groundwater.
Cleanup levels established in accordance with this hierarchy ar
legally enforceable standards in actions involving remediation
groundvater in the State of Iowa. The cleanup level for benzen
under this regulation is the EPA lifetime Health Advisory Level
of 1 ppb. Because this state standard is more stringent than t
federal standard, which is the MCL of 5 ppb, the state standard
is an applicable requirement for this remedial action.
Action-Specific ARARs
Organic Air Emission Standards for Process Vents and
Equipment Leaks at Hazardous Waste Treatment, Storage and
Disposal Facilities, 55 Fed. Reg. 25454 (June 21, 1990), to be
codified at 40 CFR $264 Subpart AA and BB, limit organic
emission* from process vents associated with air stripping
operations that manage hazardous wastes with 10 parts per milli
by weight or greater total organics. Since an air stripper wil
be used to remove organic compounds from groundwater, the
requirements of this regulation are relevant and appropriate f:
this remedial action.
-------
35
567 I.A.C. 5103.2(13) contains closure requirements for
solid waste landfills that are applicable to this action. This
regulation requires a four foot cover consisting of two feet of
low permeability compacted soil and two feet of uncompacted soil
sufficient to support shallow root vegetative growth or use of
alternative methods and aeasures which would provide equal or
superior performance. The regulation also specifies that the
final cover 8ust have a slope of between 5' and 25', that upon
completion the cover shall be revegetated to prevent soil
erosion, that a groundwater monitoring system be installed and
operated, and that a financial assurance instrument sufficient to
cover costs of post-closure activities be provided.
If carbon adsorption is used to control organic air
emissions resulting from air stripping operations, spent carbon
filters will be disposed of in accordance with the requirements
of RCRA Subtitle C.
Discharge of treated groundwater or site run-off to Hyers
Creek through a discernible conveyance such as a ditch, pipe,
culvert, storm sewer or other means is considered a direct
discharge to surface waters. Such discharge must comply with the
administrative and substantive requirements of an NPDES permit
obtained trom the State of Iowa.
Location-SDecific ARARs:
40 CFR Part 6, Appendix A, which describes EPA's policy on
implementing Executive Order 11990 (Wetlands Protection),
requires that EPA conduct its activities to avoid, to the extent
possible, the long- and short-term adverse impacts associated
with destruction or moditication of wetlands. EPA is also
required to avoid direct or indirect support ot new construction
in wetlands wherever there are practicable alternatives and to
minimize potential harm to wetlands when there are no practicable
alternatives. These requirements are applicable to this remedial
action due to the wetlands adjacent to the site.
C.
Cost-Effectiveness
The .elected remedy is cost-etfective because it will
provide overall ettectiveness proportional to its costs, the net
present value being $2,352,121. The .elected remedy ettectively
reduces the hazards posed by all of the contaminants at the site,
yet its estimated cost is les. than 2' of the estimated cost of
the alternative involving excavation and ottsite disposal and
less than 15' ot the estimated co.t ot the alternative involving
excavation and stabilization. Although Alternatives 1 and 2 are
less costly than the selected remedy, they are not protective of
human health and the environment and do not comply with ARARs.
-------
36
D.
utilization Qf Permanent Solutions ~ Alternative Treatment
Technoloav !gx Resource Recoverv Technoloaies\ tQ ~
Maximum Extent Practicable
The EPA has determined that the selected remedy represents
the maximum extent to which permanent solutions and treatment
technologies can be utilized in a cost effective.anner for the
final remedial action at the White Farm Equipment Dump Site. Of
the alternatives that are protective of human health and the
environment and comply with ARARs, the selected remedy provides
the best balance of trade-offs in terms of long-term
effectiveness and permanence, reduction in toxicity, .obility or
volume achieved through treatment, short term effectiveness,
implementability, cost, also considering the statutory preference
for treatment as a principal element and considering state and
community acceptance.
Alternatives 3, 4, and 5, which are the only alternatives
. which are protective of human health and the environment and
comply with ARARs, all provide for groundwater extraction and
treatment. Thus, the major trade-offs that provide the basis for
this decision concern remediation of contaminated soils and
wastes at the site.
The cap provided by Alternative 3 will provide a high degree
of long-term effectiveness and permanence, by reducing
infiltration and leaching of contaminants and limiting offsite
transport of contaminants via wind and surface water run-off.
Alternative 5, excavation and stabilization, would provide a
somewhat higher degree of long-term effectiveness and permanence
than the selected remedy since stabilization would reduce the
potential leaching of contaminants to groundwater to a .omewhat
greater degree than capping. Alternative 4, excavation and
offsite dispOsal, would also provide a higher degree of long-term
effectiveness and permanence than the .elected remedy since all
hazardous .ubstances would be removed trom the .ite. However,
the landfill aaterials and contaminated soils contain low levels
of contamination and the data indicate that the contaminants do
not leach into groundwater to any signiticant degree. The wastes
remaining onaite will be reliably contained by the selected
remedy, and thus the .elected remedy will provide long-term
effectivene.. and permanence.
The increased costs ot Alternative. 4 and 5 are not
proportional to the ettectiveness they vould achieve.
Alternative 3 vill provide a high degree ot long-term
effectiveness and permanence at 15' of the cost of Alternative 5
and 2' of the cost of Alternative 4. Alternative 3, through
capping the landfill and tencing the .ite, vill reduce the
mobility of contaminants and reduce the risks posed by direct
contact or ingestion of contaminated soils/vastes in a cost
effective manner.
-------
37
Significant short term and implementation difficulties are
presented by the large volume of materials that would be
excavated, treated, and replaced onsite under Alternative 5, or
excavated and disposed of offsite under Alternative 4. Both
alternatives would invo~ve disturbing a large amount of
contaminated material and thus involve negative short-term
impacts of increased noise and dust levels. Although both
alternatives involve demonstrated technologies that are
implementable, excavation and either treatment or transport of
such large volumes of material would be more difficult to
implement than Alternative 3.
The .elected remedy, Alternative 3, can be implemented and
completed with less difficulty and at less cost than Alternative
4 or 5, while atill providing a high degree of long-term
effectiveness and permanence. Alternative 3 is therefore
considered to be the most appropriate remedy for contamination at
the site because it provides the best balance of trade-offs with
respect to the nine criteria and represents the maximum extent to
which permanent solutions and treatment are practicable.
E.
Preference tgx Treatment ~ A Princi9al
Element
By extracting and treating contaminated groundwater until
health-based cleanup levels are met, the selected remedy
addresses one of the principal threats posed by the site through
the use of treatment technology. The other principal threats are
posed by the landfill materials. Treatment of the landfill
materials is impracticable due to the large size of the landfill,
the low concentration of the contaminants in the landfill
materials, and the high cost of treatment of these materials.
However, the engineering and institutional controls included in
the selected remedy will adequately and reliably manage and
contain t~e wastes left in place and achieve protection of human
health and the environment.
-------
R.soon8iv.n... 8UMMarv
The public comment period on the preferred alternative for
the White Farm Equipment Company Dump as presented in EPA's
Proposed Plan began July 8, 1990, and ended September 6, 1990.
During this period, the local community submitted numerous
comments to EPA. These comments and EPA's responses are
summarized below. Also included here are additional EPA
responses to certain comments made at the July 12, 1990, public
hearing. All of the comments submitted during the public comment
period, as well as a transcript of the public hearing, are
included in the administrative record.
Technical Asoects And Necessitv gf ~ Landfill Cover
The majority of the commentors were concerned with the
technical requirements of the landfill cover. A number of
,commentors suggested that the four foot cover requirement in the
preferred alternative was technically unnecessary and seemed to
be an arbitrary requirement. Many of the commentors requested
that EPA either select Alternative 2 or reevaluate the cap
requirements.
~ ReSDonse:
One of the requirements of any remedy selected by EPA is
that it comply with all requirements of federal and state
environmental laws that are applicable or relevant and
appropriate under the circumstances of the release or threatened
release at the site. In this case, one such requirement which is
applicable is a State of Iowa regulation which provides standards
for closure of sanitary landfills. This regulation requires that
when sanitary landfills undergo final closure, the final cover
must consist of at least two feet of low permeability compacted
soil and two feet of uncompacted soil sufficient to support
vegetative growth. The regulation also provides that alternate
materials or methods .ay be used if shown to provide equal or
superior performance.
As di8cu8sed in greater detail below, this reqUirement is
applicable to this site. It is not an arbitrary requirement; it
is a closure regulation applied to sanitary landfills throughout
the State of Iowa.
Alternative 2 does not provide for any cover on the landfill
material and does not provide any alternative .ethods or .easures
to control contaminant transport via run-off to adjacent wetlands
or to limit infiltration into landfill materials. Therefore,
Alternative 2 does not comply with the landfill closure
requirement and cannot be selected as the remedy for this Site.
-------
- 2 -
In response to the commentors who stated that a four foot
cover is not technically necessary, EPA has determined that the
Iowa landfill closure requirement is an ARAR and must be complied
with by the remedial action. Where a requirement is legally
applicable at a site, EPA does not have any discretion to
consider whether the requirement is technically necessary. EPA
notes, however, that 567 I.A.C. 5103.2(13) (b) provides for a
variance from the four foot cover requirement., At the present
time, EPA has not determined whether such a variance is
appropriate. If upon consideration of information submitted
during the desiqn phase EPA decides that a four foot cover is not
required due to technical reasons and that alternate materials or
methods will provide equal or superior performance, a variance
will be qranted in accordance with the provisions of the Iowa
regulation.
Landfill Cover Reauirement ia ngt AD ARAB
One commentor stated that the
I.A.C. S103.2(13)(b) are not ARARs
Site, and that if the requirements
ARAR waiver is justified.
closure requirements of 567
for remedial action at the
are determined to be ARARs, an
~ Response
EPA was first informed by the State of Iowa that the closure
requirements were potential ARARs for this site on June 26, 1990.
EPA subsequently identified the requirement as an ARAR in the
Proposed Plan. Following receipt of public comments asserting
that the requirement is not an ARAR, EPA contacted the State of
Iowa and asked that the state provide additional information as
to the basis for the its determination that the requirement is an
ARAR. IDNR responded to EPA's request for more information on
September2~, 1990.
EPA has carefully reviewed the Iowa solid waste statutory
provisions and requlations, the comment letters pertaining to the
ARAR, and the additional information concerning the ARAR .
submitted to EPA by IDNR. Based upon a review of all the
available information, EPA has determined that the requirements
are applicable to the .ite. The complete EPA determination that
the requir..ent i. an ARAR i. contained in the administrative
record in a September 28, 1990 Memorandum from David Cozad,
Assistant Regional Counsel, EPA Region VII. FOllowing is a brief
.ummary of the finding. of that memorandum.
Since 1987, White Farm Equipment Company or White-New Idea
(WFE) have been di.posing of .olid waste at the Site without a
permit in violation of Iowa law. IDNR has authority to compel
any person violating .olid waste laws or regulations to comply
with such laws or regulations. In order to come into compliance.
WFE must either obtain a permit or properly close the site in
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accordance with the Iowa solid waste regulations. The solid
waste regulations contain .pecific closure standards for
different types of solid waste disposal facilities, and the
specific standards which are applicable to the site are contained
at 567 I.A.C. 5102.3(13).
The commentor also asserted that this ARAR should be waived
on the basis that it has been inconsistently applied by the State
of Iowa, or in the alternative that a fund-balancing waiver
should be invoked. As is discussed in detail in the aemorandum,
EPA has determined that an. inconsistent state application waiver
is not justified since Iowa has consistently applied the
requirement in other situations and has stated that it intends to
consistently apply the requirement in the future. EPA has also
determined that a fund-balancing waiver is not justified for this
ARAR. The estimated cost of the selected remedy is relatively
low in comparison to the cost of an average CERCLA remedy. Use
of the fund to finance this remedy would not significantly
jeopardize the ability of EPA to fund remedial actions at other
sites across the nation.
The commentor also stated that the requirement was not
identified in a timely manner and thus compliance with the
requirement is not mandated. EPA agrees that the requirement
should have been identified earlier in the remedy selection
process than it was. However, the National Contingency Plan
mandates that selected remedies comply with all ARARs which are
identified prior to issuance of the Record of Decision, a. was
the case with this requirement. Moreover, the requirement was
identified as an ARAR in the Proposed Plan and thus the public
had adequate opportunity to comment on the requirement.
Cost-Effectiveness g! thA Preferred Alternative
Several commentors stated that the preferred alternative is
not cost effective and requested that EPA consider .electing a
less costly remedial alternative. One co.-entor stated that
EPA's preferred al~erna~ive is inconsi.tent with the NCP since it
is not co.~-effective in compari.on to an alternative which would
require .ivnificantly le.. cover on the landfill but would
otherwise be iden~ical to the preferred alternative.
lEA ReSDonse:
EPA evaluate. r..edial alternative. u8inq nine evaluation
criteria, one of which i. co.t-effectivene... However, an
alternative .U8t be found to be protective and ARAR-compliant
before cost effectiveness and the other balancing criteria are
considered. This remedy .election process ensures that the
selected remedy will be protective of human health and the
environment and that such protection will not be compromised by
other factors, such as cost. Cost is one of the factors that EPA
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considers when choosing among alternatives that are protectiv
and ARAR-compliant.
Alternatives 1 and 2 were found not to be protective of
human health and the environment and ARAR-compliant and theref<
were not eligible for consideration in the balancing process b:
which the remedy is selected. Alternatives 3, 4 and 5 were foi
to be protective of human health and the environment and ARAR-
compliant. Among these three alternatives, the selected remedy
is the most cost effective. The estimated cost of the selectee
remedy is less than 2% of the estimated cost of Alternative 4 i
less than 15% of the estimated cost of Alternative 5. Of the
five alternatives evaluated in detail, the selected remedy is 1
least costly alternative that is eligible for selection.
As explained above, EPA has determined that the Iowa solic
waste closure regulation which requires a four foot cover or
alternate materials or methods providing equal or superior
performance is an ARAR for this remedial action. Therefore, ar
selected remedy must comply with this ARAR. A remedy which doc
not provide any cover, such as suggested by a commentor, would
not be protective and ARAR-compliant. The cost-effectiveness c
remedies that are not protective and not ARAR-compliant is not
considered by EPA.
Long-Term Impacts
During the public hearing, several commentors raised
questions regarding the long-term effectiveness of the preferi*
alternative. Specifically, commentors wanted to know how long
materials would remain on site, whether the site would be markc
and to what degree landfill leachate could cause water quality
problems in the future. A review of the hearing transcript
indicates that only partial answers were given.
EPA Response!
\
Since landfill materials will remain in place indefinitely
this site will be subject to a five-year review to ensure that
the remedy remains protective of human health and the environme
in the long-term. The cite vill be fenced and warning signs
posted. The long-term potential for leaching of contaminants t
groundwater vill be greatly reduced by the placement of the cov
on the landfill. Migration of the existing contaminated ground
water offsite should not occur due to the operation of the
extraction well. Future land use will be limited by deed
restrictions. The selected remedy also includes a long-term
program of groundwater monitoring and fence, vegetation and cap
inspection and maintenance.
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Groundwater Remediation
One commentor questioned the need for groundwater
remediation. The comment or states that the qroundwater
remediation is based on a single sample and that the sample is
not representative of the qroundwater impacted by the landfill.
The commentor states that due to the localized nature of the
contaminated qroundwater, a removal action would be more
appropriate.
lEA ReSDonse:
The EPA recoqnizes that the available data indicates a very
localized qroundwater problem. As part of desiqn of the selected
remedy, monitoring wells will be installed and sampled in order
to completely define the extent of contamination. The additional
sampling data collected during the design phase will be used to
make the extraction system as limited as possible.
The RI/FS did not indicate the presence of free non-aqueous
phase liquids (NAPL). Unless such a source can be located, a
removal action is not justified. The selected remedy including
extraction and treatment is justified since the contaminants are
already in the groundwater and a source control removal would not
prevent the migration of contaminants offsite. Since the
contaminated aquifer is known to be used as a drinking water
source by residents down and cross gradient in close proximity of
the landfill, groundwater extraction and treatment is appropriate
at this site.
~ ~ Collected ~ EfA
EPA conducted additional sampling at the site on
1990. A commentor states that the public should have
opportunity to review and comment upon the analytical
prior to selection of the remedy.
Auqust 6,
had an
results
EfA ResDon..
The additional sampling on Auqust 6, 1990, vas conducted at
the reque.t of the Agency for Toxic Substances and Disease
Registry (ATSDR) and in response to comments received by EPA at
the July 12, 1990 public hearing. EPA sampled a number of
shallow sand point re.idential vells in the vicinity of the site
and took a number of soil samples from the .ite. Analyses of the
vell samples did not indicate any contaminant concentrations
above health-based drinking vater .tandards. The data did not
result in any modification of the preferred alternative and,
therefore, extension of the public comment period is not
warranted. The additional data is included in the administrative
record for the site.
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~
$TATE OF
I
~Jc(~
V/
TERRY E. BRANSTAD. ~
DEPARTMENT OF NATURAL RESOURCES
LARRY .J. WIL.5ON. DIA£CTOA
June 26, 1990
John P. McDonald
Remedial Project Manager
Remedial Enforcement Section
Superfund Branch
Waste Management Division
USEPA, Region VII
726 Minnesota Avenue
Kansas City, KS 66101
RE: White Farm Equipment Company
.. .-...
RECEIVED
~ 6" J990
RE:Ma ~.N
Dear Mr. McDonald:
We have had an opportunity to review the Proposed Plan for the
above referenced site. We concur with the preferred alternative
for White Farm Equipment Company Dump, which is Alternative 3:
Surface Controls, Slope Stabilization, , Ground Water Treatment.
The following comments relate to our concern about
information contained in the Proposed Plan.
(1) Under Site Background, the listed results of the Remedial In-
vestigation are shown. In the second item, it states "the flow
direction of the upper unconfined aquifet is to the
west/southw~st, away from Charles City." We feel that the word
'wells' should follow the words 'Charles City'.
some
of
the
(2) Under Site Background, the listed results of the Remedial In-
vestigation are shown. In the third item, it uses mg/l as units
of levels of organic contaminants found at one location. We feel
that mg/l. should be changed to ug/l, in all four cases, as ug/l
is the unit of levels found in TABLE 1 of the plan.
(3) Under Site Background, the listed results of the Remedial In-
vestigation are shown. In comparing the fourth and fifth item, a
contradiction seems to exist. In the fourth item, it implys that
a level above normal levels of metals were found in the surface
water drainage routes, while in the fifth item, it atates that
metal analyses of the surface water drainage path indicated lev-
els comparable to typical concentrations found in the U.S.
(4) Under Site Background, the listed results of the Remedial In-
vestigation are shown. In item four, information pertaining to
surface water, surface water availability, and surface water sam-
ples could be seperated from item four and placed in an aeparate
item for viewing.
(5) Under Summary of Alternatives, the second paragragh of Alter-
native 3 should make reference to the fact that the 'organically'
WALLACE STATE OFFICE BUILDING I DES MOINES. IOWA 503"/5'~28'.S'.sl T1IO 515-242-5167 I fA! Sl\ 1'1: 8Jq')
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John P. McDonald
Page 2
contaminated groundwater would be captured from extraction
and that treatment/removal of 'organically' contaminated
water would then be achieved by carbon adsorption or air
ping.
We feel that the rest of the Proposed Plan adequately addresses
the concerns at the site.
wells
ground
strip-
Sincerely,
:J:~ iI~
Jim Thayer
Environmental Specialist
Solid Waste Section
JT:jt
"
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Telephone Conversation Record
Date:
7-6-90
Participants:
Morris Preston, IDNR
John P. McDonald, EPA Reqion VII
Summary:
I called Morris to confirm the states concurrance on the
Preferred Alternative for the White Farm Equipment (WFE) Co. Dump
Site. I explained that the proposed plan had been modified to
include the contingency for treatment of metals contamination in
ground water as necessary. I also informed him that the
Preferred Alternative was now in compliance with the LAC 567-
103.2(13) governing closure of landfills.
Morris agreed that the state concurrs with the Preferred
Alternative at the WFE site. I thanked Morris, and said that I
would offer him a copy of this Conversation Record.
Documented By:
Date:
John P.
7-6-90
McDonald ~~;1l -
~~~,~~
@
. .~
.'
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