United States
Environmental Protection
Agency
Office of
Emergency and ,
Remedial Response
EPA/ROD/R05-85/018
August 1985
Superfund
Record of Decision
Old Mill, OH
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TECHNICAL REPORT DATA
(Please read Instructions on the reverte before completing}
1. REPORT NO.
EPA/ROD/R05-85/018
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
SUPERFUND RECORD OF DECISION
Old Mill, OH . r
5. REPORT DATE
August 7, 1985
6. PERFORMING ORGANIZATION CODE
7. AUTMOR(S)
8. PERFORMING ORGANIZATION REPORT NC
9. PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
Final ROD Report
14. SPONSORING AGENCY CODE
800/00
15. SUPPLEMENTARY NOTES
16. ABSTRACT
The Old Mill site is in the village of Rock Creek, Ashtabula County, Ohio.
The site consists of two parcels of land; the Henfield property and the Kraus
property. Land use in the vicinity of the site is represented by a mixture of
residential, agricultural, and commercial/industrial developments. The Henfield
property is approximately three acres, and includes four dilapidated wood buildings
and four concrete silos. The Kraus property is approximately ten acres, partially
covered with piles of railroad ballast, and has one empty abandoned bulk liquid
tank. In 1979, the U.S. EPA and Ohio EPA found approximately 1,200 drums of toxic
waste, including solvents, oils, resins and PCBs, stored on both the Henfield and
Kraus properties. Superfund emergency removal activities and enforcement actions
resulted in drum removal that began in November 1981 and was completed by October
1982. Today, contaminated soil and ground water remain on-site.
The selected remedial action includes: removal and off-site disposal of a
select volume of contaminated soil; extraction and treatment of contaminated ground
water; aquifer use restrictions; and providing alternate water supply. Total capital
cost for the selected remedial alternative is estimated to be $3,917,000 with O&M
costs approximately $45,000 per year.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS.'OPEN ENDED TERMS
c. COSATI I leM.Ct
Record of Decision
Old Mill, OH
Contaminated Media: soil, gw, sw, sediment
Key contaminants: VOCs, solvents, oils,
resins and PCBs
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SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
OLD MILL SITE, ROCK CREEK, OHIO
SITE LOCATION AND DESCRIPTION
The Old Mill site ts tn the Village of Rock Creek, Ashtahula County, Ohio.
The site consists of two parcels of land; the Henfleld property and the
Kraus property. The Henfleld property 1s approximately 3 acres, and
Includes four dilapidated wooden buildings and four concrete silos. Surface
water flow from the property drains to the southwest corner and then to a ditch
which dlsharges to the Rock Creek. The Kraus property Is approxlnately 10
acres, 1s partially covered with piles of railroad ballast, and has one empty
abandoned bulk liquid tank. Surface water flow from the Kraus property drains
toward the northwest to a ditch wMch discharges to Badger Run and to the Grand
River. Land use 1n the vicinity of the sice Is represented by a mixture of
residential, agricultural, and commercial/Industrial developments. The slta 1s
In a rural village setting with the closest residences approximately 75 feet
from the property boundary (Figure 1). .
The site geology for both properties Includes clayey s1H over 10 feet
of glacial till that overlies 2 feet of weathered shale. The groundwater
surface 1s 3 to 5 feet below ground surface. Groundwater movement at the
Henfleld property 1s toward the west, and at the Kraus property 1s toward the
northwest, and occurs principally 1n the glacial till and weathered shale above
the bedrock. The area 1s considered poor for domestic well supply development.
Although most residents are using an available municipal drinking water source,
there are two Identified downgradlent residences using the groundwater. The
estimated horizontal linear velocity of groundwater Is 20 feet per year at the
site.
SITE HISTORY
Response activity at the Old Mill site began In 1979 when U.S. EPA and Ohio EPA
found approximately 1,200 drums of toxic waste, Including solvents, oils, resins,
and PCBs, stored on both the Henfleld and Kraus properties. The Henfleld property
was considered to be an Immediate hazard because a significant quantity of the
drummed waste was flammable. Access to the site was not controlled. Superfund
emergency removal activities and enforcement actions resulted In drum removal
that began In November 1981 and was completed by October 1982. In addition,
approximately 2 Inches [80 cubic yards (yd3)] of soil from the drum storage
areas on the Henfleld property were removed 1n November 1982. A six foot cyclone
fence was Installed around a portion of the Henfleld property 1n April 1984
under the authority of Section 106 of the Comprehensive Environmental Response,
Compensation and Liability Act (CERCLA), 1n order to minimize the potential for
direct contact with the remaining soil contaminants.
CURRENT SITE STATUS
A remedial Investigation (RI) was conducted at the Old Mill site from August 1983
to December 1984. The activities performed Included Installation of groundwater
-------
HENFIELD
.. PROPERTY
W I
*' /•?,'
-------
monitoring wells, and collection, analysis, and evaluation of private well water
samples, soil and sediment samples, surface water and groundwater samples,
railroad bed samples, and railroad ballast samples. In addition, geophysical
studies were conducted, and topographic maps were prepared for both the Henfleld
and and Kraus properties.
Results of the RI are summarized according to environmental medium 1n Tables 1
and 2 and Figures 2 through 5. Concentration ranges are displayed for each
contaminant detected.
Potential risks from contaminated soil and groundwater on the site are based on
the assumption that tne site would be used 1n the future for both residential
and 1ndustr1al/comm2rc1al development. These risks are theoretical quantifica-
tions, and are reported as excess lifetime cancer risks. Excess lifetime
cancer risk 1s defined as the Incremental Increase 1n the probability of getting
cancer compared to the probability 1f no exposure occurred. For example, a
10*6 excess lifetime cancer risk represents the exposure that could Increase
cancer by one case per million people exposed. The risk levels were calculated
using U.S. EPA Carcinogen Assessment Group cancer potency values.
Soil Contamination
The Henfleld property soil has elevated levels of organic ard Inorganic
contamination. Organic contaminants were Identified down to 6 feet below
ground surface. Ingestlon of 0.1 to 1 gram per day for seventy years of
contaminated soil would result 1n a calculated excess lifetime cancer risk
between 10~3 and 10-*. The Kraus property soil has significantly lower levels of
contamination with Ingestlon risk levels between 10~5 and 10~6. The volume
of contaminated soil 1s estimated to be 18,301) yd3.
Groundwater Contamination
Groundwater at the Henfleld property 1s contaminated with volatile organic
compounds (VOCs), mainly trlchloroethene, with lower concentrations of tetra-
chloroethene, trans-dlchloroethene, I,l-d1chloroethene, vinyl chloride, and
1,1,1-trlchloroethane. Ingestlon of 1 to 2 liters per day for 70 years.of
contaminated groundwater on the Henfleld property site would result In a
calculated excess lifetime cancer risk greater than 10-3.
Groundwater at the Kraus property 1s contaminated with VOCs, mainly ethyl benzene
and xylene. The VOC plume appears confined to a small onslte area on the east
side of the property. Ingestlon of contaminated groundwater on the Kraus
property would not result 1n a calculated excess lifetime cancer risk but would
result 1n a toxic risk because the concentration of ethyl benzene exceeds the
Acceptable Dally Intake value.
There are at least two residences within 1/4 mile of the site that presently use
groundwater wells for a drinking water source. These wells are not presently
affected by the site, however 1t 1s projected that local water supplies may be
affected 1n the future by movement of contaminants offsite.
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T*le I
RANK OF OONrAHlNANT OTTNCfKIMATIONS AM)
iwrwriY, am HIIJL sire
Drainageway
Onsttc Soil (MK/VK)
Contaminant
ORGANIC
FHAs
Phenols
rcns
Ttithalntes
Pesticides
Trrthloroetheiie
Acetone
Oilier Chlorinated
F.thencs
Ethyl Benzene
INTOCAM1C
Arsenic
Calmium
Cl itomium
lead
Nickel
Scleoiim
Zinc
Surface
7.4-13,440
13-180
0.0025-0.0173
3.70-3,700
U
1.56-1.220
U
0.405-554
0.019-1.420
102
0.47-152
64-221
59-8,370
22-353
35
110-8.6)0
>r
0.106-196
2.7-5.4
0.003-11
0.91-11.68
U
0.017-570
U
U
U
31
8.7
*
72-984
24-59
2.5-16
147-963
Offsite Soil (ngAg)
Surface
1.7-9.29
2.65
0.0088
0.610
0.192-0.735
0.414-3.3
U
0.005
U
*
0.99-1.93
*
82-153
21
0.27-0.74
272
>r
1.18-36.8
U
0.0814-0.19
0.66-120
U
0.0049-0.22
0.0518-18
0.016-0.099
U
*
0.57
*
80
26.3-29.5
0.3-1.86
119-154
Sediment
(ng/fcg)
U
U
0.069-0.248
2.94
0.0057-7.955
U
0.032
U
U
*
0.63-1.54
*
85.1
24.7-26.6
0.3-0.5
109-165
Surface
Water
(ug/L)
U
U
U
U
U
"22-97
49-280
7-135
U
U
1.1
U
U
U
U
19-73
Crourdvater (ug/L)
Offsite9
Wells
•_
U
U
U
U
U
89.9-6,100
U
14.9-490
22.2
122
U
100
59
U
<2
U
Onsitca
Wei la
U
U
U
56
U
1,100
127- 1,000
U
U
U
I
11
U
40-45
2
14-96
II • Ui»telected.
•-Detected but not above background.
"Values reported are of dissolved contaminants.
HflE: Where only one v.iluc in given, contaniiuint was detected in only one san^le above background or standard at the
roncentr.ition shoun. Contaminants are those that exceed the upper Unit of the 95-percent confidence interval for
background concentrations in soil or drinking water standards and criteria in water. Values for soil and sediment
reported on a dry weight basis.
-------
e 2
HANCF. OY CONTAMINANT t s U
U
U
29
0.5-430
*
64
23-27
0.25-1.0
115-274
>r
53.884
U
U
I)
U
U
0.0068-0.11
0.003-0.125
0.0465
0.0526-0.0686
U
37-59
0./.3
*
110
24-48
0.5-0.7
300
Drainneevay
—••• * •• ' ' • • - •• i •» -.-^^M^^^M—
Surface
Sediment* Water
(ug/l.)
17.19-23.13
U
0.031
U
U
U
U
U
U
U
U
8.2-13.6
0.18-0.39
9.3-18.5
13.3-20.8
I8.8-/.7.I
0.14-0.36
74-138
U
U
U
U
U
U
U
U
U
U
U
10
U
U
U
U
U
11-35
Ground-
wat erb
(ug/t)
0.27-45.75
10-580
U
<0.2-
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OlO Mtu 2f?»M
MARTIN MOBILE
MILLING
HENFIELO PROPERTY
KEY
EXISTING FENCE (APPROXIMATE)
—— HENPIELD PROPERTY ORAINAGEWAY
CONCENTRATION RANGES (mg/kg) DRY WEIGHT
(BACKGROUND CONCENTRATION 64 mg/kg,
INCLUDES 63 mg/kg BENZOIC ACID)
• 0-10
• 11-100
• 101-500
• 501-1.000
1.001-2.000
2,001-4.000
4,001-8.000
> 8,000
60
SCALE IN FEET
120
(PROPERTY BOUNDARIES ARE APPROXIMATE)
Figure
CUMULATIVE CONCENTRATION (mg/kg)
OF VOLATILE AND SEMIVOLATILE
ORGANICS IN ONSITE AND OFFSITE
SURFACE SOIL
Heniield Property
Old Mill Site
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OLD MILL J«S
-------
OlO MILL >'2VIS
MARTIN MOBILE
MILLING
HENFIELD PROPERTY
KEY
EXISTING FENCE (APPROXIMATE)
HENFIELD PROPERTY ORAINAQEWAY
• GROUNOWATER MONITORING WELL
•—• CONCENTRATION ISOPLETH (ufl/L)
BMOL BELOW METHOD DETECTION LIMIT
0 60 120
SCALE IN FEET
(PROPERTY BOUNDARIES ARE APPROXIMATE)
Figure 4
CUMULATIVE CONCENTRATION OF
VOLATILE ORGANICS IN SHALLOW
WELLS, DECEMBER 1984
Henfield Property
Old Mill Site
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OLD MILL J'SVIS
\
X
KEY
MARSHY AREA
STOCKPILES OP RAILROAD BALLAST
KRAUS PROPERTY DRAIN AC? EW AY
QROUNOWATER MONITORING WELL
CONCENTRATION ISOPLETH (ug/U
BELOW METHOD DETECTION LIMIT
ONLY ACETONE DETECTED
200 400
SCALE IN FEET
(PROPERTY BOUNDARIES
ARE APPROXIMATE)
Figure 5
CUMULATIVE CONCENTRATION OF
VOLATILE ORGANICS IN SHALLOW
WELLS, DECEMBER 1984
Kraus Property
Old Mill Site
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- 3 -
Surface Water and Sediment Contamination
The dralnageway originating at the southwest corner of the Henfleld property
has only limited organic contamination. In the Kraus property dralnageway,
low levels of organic contamination are present 1n the sediment. There 1s
a low probability of human health risks from exposure to surface water because
there are few potential receptors, and the dralnageways only Intermittently
contain water. Ingestlon of 0.1 to 1.0 grams per day for 70 years of con-
taminated sediment on the Kraus property wouH result 1n a potential excess
lifetime cancer risk of about 10-*.
ENFORCEMENT (See Attachment)
ALTERNATIVES EVALUATION
The major objective of the FS was to evaluate remedial alternatives using a
cost-effective approach consistent with the goals and objectives of CERCLA.
The National 011 and Hazardous Substances Contingency Plan (NCP), 40 CFR Part
300.6R, defines a cost-effective remedial action as "the lowest cost alternative
that 1s technologically feasible and reliable and which effectively mitigates
and minimizes damage to and provides adequate protection of public health,
welfare or the environment". The NCP outlines the procedures and criteria to
be used 1n selecting the cost-effective alternative.
An environmental assessment presented 1n Chapter 2 of the FS determined that
both source control and offsite (management of migration) measures are necessary.
A comprehensive 11st of appropriate remedial response technologies was Identified
for source and migration control, and these technologies were screened based on
the characteristics of the site, the characteristics of the waste materials at
the site, and the ability of the technology to address criteria such as adeauate
protection of human health and the environment and minimization of contaminant
migration. These technologies were further screened on the basis of technical
feasibility, Including an assessment of performance, reliability, 1mplementab1l1ty
and safety, and on the basis of order of magnitude costs. The following technologies
were considered applicable to site conditions and problems.
o Soil/Sediment
Multimedia cap
Clay cap (non-1nf1ltraton reduction
cap)
Landfill
Incineration
o Groundwater
Extraction system
Carbon adsorption
Publicly owned treatment works (POTW)
Public water supply
Direct discharge
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- 4 -
Based on the applicable technologies that were carried forward from this
Initial screening, alternatives were developed to address the overall
contamination at the site (see Table 3). This Initial screening 1s
consistent with 300.68(h) of the NCR. These alternatives were generally
evaluated and compared to public health and environmental criteria. No
alternatives were eliminated from further consideration based on this step.
DETAILED ANALYSIS OF ALTERNATIVES
All alternatives (except the limited and no-action alternatives) Involve
grounrtwater treatment (offsite measures) and soil removal or containment
(source control measures). The effectiveness and ramifications of each
alternative were evaluated on the basis of technical and environmental
considerations.
For the technical analysis, each alternative was evaluated on performance,
reliability, effectiveness, and 1mplementab1l1ty. For the environmental and
public health analysis, each alternative was evaluated for compliance with cederal
and State environmental laws and regulations, protection of human health and
welfare, and effects on Institutional parameters 1n order to screen out those
alternatives which may not meet public health and environmental goals. The
detailed cost analysis for each alternative Includes estimates of operation and
maintenance (OSM) costs, capital costs, and development of present worth costs
(Tables 4 through 11). The expected accuracies for cost estimates are within
+50 and -30 percent of the actual cost. This detailed analysis of a Halted
number of alternatives 1s consistent with Section 300.fifl(1) of the NCR.
Using the Information developed 1n the detailed analysis, alternatives
were compared within categories to eliminate those which were less cost-
effective. Twelve of the twenty alternatives were eliminated from further
consideration Including:
Alternatives Involving direct discharge or treatment of the groundwater at a
POTW. Direct discharge of contaminated extracted groundwater to the dralnageways
at the site, to Rock Creek, and/or to the Hrand River 1s unacceptable from an
environmental, Institutional, and public health viewpoint because o* the effluent
concentrations. Contaminants would be transferred from one environmental
medium (groundwater) to another {surf ace water ^-. Treatment of extracted groundwater
would remove the contaminants from the environment, however, treatment at a
POTH 1s more expensive than onslte treatment: annual O&M costs are about $340,00n
per year for the POTW and only about $8,000 per year for onslte treatnent. The
transportation requirements of this technology are also a major disadvantage.
Alternatives Involving offslte soil Incineration. The capital cost to transport
and Incinerate the soil 1s much greater (order of magnitude greater) than all
other alternatives. Although removal and subsequent destruction of organic
contaminants 1s permanent and Irreversible, the metals which may be physically
bound to the ash may require that the ash be disposed of at a RCRA-Hcensed
landfill. The only RCRA Incineration facility Identified within the geographical
area (300 mile radius) of the site will only accept soil which 1s packed 1n
drums. Also, the facility can .process 160 drums per month (45 yd3 per month),
and has no storage capacity. To Incinerate 95 percent (4,300 yd3) or 100 percent
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Table 3
ASSEMBLED ALTERNATIVES FOR OLD MILL SITE
Alternative
Category Numl
1.
2.
3.
l».
5.
6.
Complete
Removal
Attains
Standards
Exceeds
Standards
CERCLA
Limited Action
No Action
IA
IB
2A
2B
2C
3A
3B
3C
3D
3E
3F
4A
4B
AC
40
•t
6
Technology For;
Soil /Sediment8
Offsite landfill
Offsite incineration
Multimedia cap
Multimedia cap
Multimedia cap
Onsite incineration
Onsite incineration
Onsite incineration
Onsite landfill
Onsite landfill
Onsite landfill-
Clay cap
Clay cap
Clay rap
Clay cap
Fence
No action
Croundwater0
RCRA treatment facility
RCRA treatment facility
Onsite treatment0
Direct discharge
POTU
Onaite treatment0
Direct discharge.
POTU
Onsite treatment0
Direct discharge
POTU
Public water supply
Direct discharge
POTU
Onsite treatment0
Monitor
No action
Surface Water
No action
No action
No action
No action
No action
No action
No action
No action
No action
No action
No action
No action
No action
No act ion
No act inn
Monitor
No action
aLandfill and incineration technologies will be preceded by excavation of soil.
hCronndwater treatment will be preceded by installation of French drains and/or extraction wells.
°Onsitc treatment technologies are air stripping and/or direct contact carbon adsorption.
-------
Table
Cast Ireakdom for Atseebled Alternative 1A
Assembled Alternative 1A i
leMdial Action
Soil
fannying
Mobilisation
Excavation
Transport/Hani fest
Disposal
Iccifill aod Revegetate
fcMlitioa
Ciosore
GrooadMter
farvtyino.
Mobilization
Construct Extraction Systsi
Eitrietioa Syitu (Q i (!)
Truiport/IUnifest (0 i It)
BroaadMttr Itanitoring
dosure/ltonitoring
SUBTOTAL
Replacement Costs (c>
Offsite RCRA Landfill. 1001 Reooval,
Qffsite RCRA 6round»ater Treatment
Construction
t408,000
t479,000
t38S,000
tsar.ooo
t3, 123,000
1211,000
1433,000
110,000
124,000
1118,000
to
to
124,000
110,000
13, 903,000
Cipital (a)
1563,000
UA2,000
1532,000
1802,000
14,309,000
1291,000
1598,000
114,000
1130^000. .
136,000
1163,000
to
10
132,000
114,000
13,146,000
Cost Estimates
Annual operation
and Maintenance
to
to
to
to
to
to
to
to
to
to
12,000
16,728,000
to
S37,000
16,767,000
north '(b)
1!63,000
1662,000
1532,000
1802,000
14,309,000
1291,000
1!98,OCO
114,000
1130,000-
136,000
1163,000
121.000
U3, 424,000
«2,0-JO
1363,000
1:1,93?, ceo
leo.Ov1)
TOTAL l?2,0:a.008
20 gircint
(at Capital cost is calculated as construction cost wltiolitd by 1.38 to incluoi indtrict caoital ::us. tndirsct
capital costs ioeludi 13 pircint for mginMring ana design, S percent for legal feu/pirait costs, and "
for contingencies.
(b) rVtsent north at 10 percent interest over 30 years. Unifon series present »orth factor 9.4169.
(c) Replacettnt cost at 10, 20, and 30 years calculitfd by using oresent north factors 0.39, 0.15, ind O.Oi
respectively. The cost of cap replacement at 30 years is ineluoeo.
-------
Table 5 Cost Breakdown for Assembled Alternative 2.1
Assembled Alternative 2A : Hultiaedia Cap, No finoval, Onsiti BroundMter Treatment
Cost Estimates
Raoedial Action
Soil
Surveying
Nobilitation
Fencing
Contouring
Cap Construction
Detention
Closure/Monitoring
Srounduttr
Surveying
Robiliutien
Conitruet Extraction Systn
Extraction Systeo (Q I H)
Treatient Systee
Treatient Sytte* (0 1 in
fifoundwter Hani tor ing
Cloture/Ronitoring
SUBTOTAL
Replacement Costs (c)
Cpaitruction
1410,000
t422,000
19,000
113,000
1224,000
1433,000
$1,000
M9.000
147,000
1113,000
to
155,000
to
$24,000
» 13, 000
12,038,000
Capital (a)
tS65,000
1853,000
tl2,000
119,000
1310,000
tsw.oco
fl,000
t99,000
145,000
t!43,000
to
«76,000
to
«32,000
118,000
12,812,000
Annual Ooeration
and Haintenance
to
to
to
to
14,000
to
to
to
to
to
12.000
to
16.000
to
t37,000
$49,000
Pre*ent
north (b)
V565.000
$858,000
t 12, 000
$19,000
$345,000
$598,000
$1,000
$95,000
$65,000
$163,000
121,000
$76,000
t33,000
$32,000
$367,000
tt, 272, 000
$106,000
TOTAL
t3,378,000
(a) Capital coit it calculated at construction cost wltiplied by 1.38 to include inoirect caoital costs, incirect
capital costs include 13 percent for engineering and design, S percent for legal fees/oeriit costs, in4 20 aercent
for contingencies.
(b) Present north at 10 percent interest over 30 years. Unifori series present »orta factor 9.4269.
«c> RMlacnent cost at 10, 20, and 30 years calculated by using present north factors 0.39, «).IS, and 0.06
respectively. The cost of cap replactaent at 30 years is included.
-------
Table fj Cost Breakdown for Asseabled Alternative 20
Assetbled Alternative 20 i
Remedial Action-
Soil
Somying
RoailUation
Excitation
Transport/Manifest
Biipoul
laciflll
Fencing
DtMlitioa
Clowri/llonitoring
Brooadvater
Sorvtying
ItobtiiMtioii
Coostroct Extraction Systee
Extraction Systn (0 k H)
Treatment Systee
Treatment Systee (0 t Hi
BroundMter Honitoring
Clourt/Honitoring
SUBTOTAL
Replaceemt Costs (c)
931 reeoval, Offsite RCRA Landfill,
Onsite SroundMter Treatient
Construction
$408,000
4479,000
1246,000
1 140,000
$732,000
144,000
19,000
1433,000
11,000
$69,000
M7.000
$118,000
$0
$33,000
$0
$24,000
$13,000
$2,838,000
Capital (a)
$363,000
$662,000
$340,000
$193,000
$1,037,000
161,000
$12,000
$398,000
11,000
$93,000
$63,000
$163,000
$0
$76,000
$0
$32,000
$18,000
$3,917,000
Cost Estieates
Annual Operation
and Haintenanca
$0
$0
$0
$0
$0
to
$0
$0
to
to
to
to
12,000
to
16,000
to
137,000
143,000
Pr»:) Rcplaciient cast at 10, 20, and 30 vtars calculated Ey usinq ortsent «ort!) factors <).*?. O.il. inj O.Oo
rnoectivtly. The cost of cap rtplactttnt at 30 years is included.
-------
Tablt 7 Cost Breakdom for Assembled Alternative 2F
Assembled Altirnitive 2F :
ftettdial Action
Soil
Surveying
Hobilization
Fencing
Eicivition
Transport/Manifest
Landfill Construction
Backfill
Oeiolition
Cloiure
SroundMter
Surveying
Robilization
Construct Extraction Systn
Extraction Syitu (0 I N)
Treattent Systet
Treatmnt Syttci (0 t II)
8round»ater Monitor ing
Closure/Honi coring
SUBTOTAL
Replacement Costs (c)
TOTAL
951 rttoval, Qnsitc
Onsite Groundnater
Constniction
•408,000
1479,000
19,000
$244,000
$14,000
•964,000
•44,000
•433,000
(10,000
•69,000
•47,000
•118,000
•0
$35,000
(0
•24,000
•13,000
•2,333,000
Landfill,
Treatment
Capital (a)
•
•363,000
•662,000
•12,000
•340,000
•20,000
•779,000
•61,000
•398,000
•14,000
•93,000
•63,000
•163,000
•0
(76,000
•0
•32,000
•18,000
(3,498,000
Cost Estimates
Annual Operation
and tlaintwunce
•0
•0
•0
•0
(0
to
•2,000
(0
•0
•0
to
to
(2,000
•0
$6.000
to
$37,000
$47,0*00
Present
north (b)
$563,000
$662,000
$12, COO
$340,000
120,000
t779,000
$80,000
1598,000
(14,000
(93,000
(65,000
$163,000
(21,000
(76,000
$53,000
(32,000
$367,000
(3.941,000
(106,000
(4,047,000
(a) Capital cost is calculated as construction cost tultipiied by 1.38 to include inoirect cioital costs, inc-.rect
capital costs include 13 percent for engineering and design, 5 percent for legal fees/pernt costs, and :<;• :srcsnt
for contingencies.
(b) Present North at 10 percent interest over 30 years. Unifori series present north factor 9.4269.
(c) Seolacjuent east at 10, 20, and 30 years calculitsd Bv asinq srssint north factors 0.3C, O.I*, ird v.vo
resoectivelv. The cost of c*o replaceaent at 30 years :s included.
6-96
-------
Table .8 Cost Breakdom for Assembled Alternative SO
Assembled Alternative 30 :
RtMdial Action .
Soil
toroyino,
Mobilisation
Fencing,
Excavation
Truaport/IUaifist
UtfflU Cooilmctioo
ItckfiU 1 RmgitiU
Otttlltioa
Clossre
SrondMtir
Surveying
Robilization
Construct Extraction Systsi
btrutioa Systee (0 I H)
Trutamt Syitit
Trwtttflt Syttn (0 I B)
BrotmdMtfr Itonitortnq
Clomri/Honitarinq
SUBTOTAL
Rtpltcmnt Coits (c)
TOTAL
QnitU landfill, t
Oofiti BroundMttr
Conttruction
1408,000
tm.wo
19,000
1383,000
b)
1563,000
166:, 000
I12,COC
1332,000
181,000
13,229,000
• IIE4.000
1399,000
t 14, COO
19!,::
163. OOu
t!43,OCO
«i.OOO
176.000
135,00-1
i::,oo>>
-------
Tib 11 9 Cost ktakdowi (or Assttbled Alttrnativt 40
Assttbltd Alttrnativt 4D i Clay Cap, No Rttoval, Onsitt
Groundvattr Trtatttnt
Rmdial Actioa
Soil
Surviving
Mobilisation
Ftocing
Contouring
Cap Conitruetion
DMolitiofl
Closori/ltoni taring
IroundMtir
Survtying
Mobilization
Construct Extraction SyttH
Extraction Systu (0 t H)
Triatant Syttn
TriatMflt Syitu (GUI)
BroondMttr Monitoring
Closurt/Honitoring
SUBTOTAL
Rtplaciitnt Caiti (el
TOTAL
Cooitroetion
1410,000
tt22,000
19,000
113,000
1144,000
$433,000
<1,000
M9,000
147,000
1118,000
M
195,000
M
124,000
113,000
11,977,000
Capital (a)
1343,000
«838,000
112,000
119,000
*22a,000
1398.000
11,000
$95,000
$49,000
$143,000
10
$74,000
$0
$32,000
$18,000
$2,728,000
Cost Estiutu
Annual Ooiration
and Haiotmanct
$0
$0
$0
$0
$4,000
$0
$0
$0
$0
$0
$2,000
$0
$4,000
$0
$37,000
$49,000
*
Prtstnt
Morth (b)
5363,000
$838,000
$12,OCO
$19,000
$241,000
$398,000
$1,000
$95,000
$43,000
$143,000
$21,000
$74,000
$35,000
$32,000
$347,000
12.198,000
$104.000
$3,294,000
(a) Capital cost is calculattd at construction cost raltiplitd by 1.38 to include indirtct capital costs, inoirtct
capUal costs incluot 13 ptrcmt for tngioMring and oisign, 3 ptrctnt (or ligal (ns/oiriit costs, and 20 otrctnt
(or contingmcits.
(b) Prmnt wrtb at 10 ptrctnt iattrtst ovtr 30 ytars. Uatfort strits prtstnt vcrth (actor 9.4249.
:c) RtolacMtnt cost at 10, 20, and 30 ytars calculattd By using ortstnt wrth (actsri 0.39, O.lS, tnd O.Oi
rtsptctivtly. Thi cost o( cap rtplactunt at 30 ytars it incluSto.
-------
Tablt 10 Cost Briakdonn for Atsttblcd Alttrnativt 5
AssMbltt Altirnativt 3 s
RlitdUl Action •
Soil
Sonrvying
Facing
furlact Mattr Control
bfoty
SroaadMtar Honitoring
SUBTOTAL
RiplacNtnt Costs (c)
Lititri Action
Construction
11,000
sf.OOO
10
14,000
124,000
138,000
Capital (a)
12,000
» 12, 000
10
«S,000
t32,000
152,MO
Cost Estioatis
Annual Operation
and Haintifunct
»0
SO
«0
»0
124,000
124,000
Friscnt
north ID)
»2,000
S 12, 000
(0
15,000
1 259, 000
1279,000
119,000
TOTAL
1297,000
U) Capital cost is cilculatid as construction cost tultiplitd by 1.38 to includt indirtct capital costs, indirect
capital costs includi 13 ptrcint for mginttring and disign, S pircmt for ligal ftn/pirnt costs, and 20 ptrcint
for contingmciis.
(5) Prtsmt Mirtl) at 10 ptrcint lattrtst ovtr 30 yiars. Unifori siriis prisint worth factor 9.4249.
(C) Rtplactitflt ccit at 10, 20, and 30 ytars calcuUttd by using pristnt aorth factprs 0.39, 0.15. and 0.06
rnpictivily. Thi cast of cap riplacntnt at 30 ytars is includtd.
-------
Tabli 11 Cost Brtakdowi for Auitbled Alttrnatm 6
Attnblid Alteriuttvi 6 : No Action
Rartul Action
Conitnjction
Soil
SroaadMttr
M
M
Cost EltiMtis
Capital
M
Annul Opirmon
and Rainctnanci
10
to
rristnt
Morth
to
TOTAL
to
to
to
to
-------
(18,300 yd3) of the soil contaminants would require 10 or 20 years. Therefore,
although the long term effectiveness may be beneficial, the length of time for
implementation of such action and the cost of incineration do not make this an
acceptable alternative.
Alternatives involving on-site incineration. The capital cost is greater than
twice the cost of all other on-site alternatives. The ash itself may be a
hazardous substance, and may therefore have to be disposed of at a RCRA facility.
The additonal cost of landfill ing the resulting ash has not been included in
this estimate. This cost will substantially increase the overall cost if
landfilling is necessary. The effectiveness and availability of an on-site
incinerator is guestienable. Presently there are few mobile incinerators. It
is estimated that incineration of 100 percent of the contaminated soil would
require 32 months of continuous operation after the inc.inerator becomes available.
Incineration of 95 percent of the soil contamination would require Ifi months after
the incinerator becomes available.
Treatment of groundwater on site was assessed for air stripping and activated
carbon. Both are demonstrated, effective treatment technologies, both remove
the contaminants of concern at the site, and both have comparable capital costs.
Because the OSM cost and effort necessary to maintain the air stripper exceed
that of the activated carbon system, the preferred treatment technology is
activated carbon.
DETAILED DESCRIPTION/EVALUATION OF ALTERNATIVES
A comparative evaluation of the remaining alternatives is presented
below and is summarized in TaMe 12. The environmental laws which may be
applicable or relevant to the remedial alternatives are discussed in the
section entitled Consistency With Cther Environmental Laws.
Alternative 1A
"his alternative consists of removal and off-site disposal of contaminated soil
and groundwater. This alternative exceeds relevant and applicable standards.
To remove soil to background levels would require the removal of 18,300 yd^ of
soil over 2.3 acras down to an average depth of 5 feet. In addition, approximately
78 yd3 of contaminated sediment would have to be removed. Approximately 760
million gallons of groundwater will be extracted over a period of 90 years to
obtain groundwater background concentration levels. The buildings on the site
will be demolished and transported to an appropriate offsite disposal facility.
All excavated soil will be transported to a permitted hazardous waste landfill
and contaminated groundwater will be extracted and transported to a permitted
treatment facility. All contaminated soils will be placed in cells which meet
RCRA requirements. (The cost estimate includes the incremental cost of construction
of a double-lined versus a single-lined cell at a licensed landfill). The
transportation costs of liquid and soil to off-site facilities are estimated by
assuming the facility to be within a 300-mile radius of the site. There are at
least three hazardous waste landfills within this area.
-------
TABLE 19
FINAL COMPARISON MATRIX
uuiwnm mail*
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tu.il n. iilal hM cai-
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d IMI nMckliuv.
M*J> Ml IMllll
Ml
ili — ir
M M''.
*.»••
*OIMM IM •ucatlia*
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Jli-
tiillic.
CwlMMVMtl I** OMJ
U c«K4i«« Mtk.
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i.nu
i.m
lwl.1 trli.n i:
urn! omtfl
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-------
Removal and disposal of all solids can be Implemented quickly and easily with
conventional construction methods. The technical feasibility of groundwater
extraction and offslte disposal 1s well established, however, because the shallow
aquifer at the Old Mill site exhibits low hydraulic conductivity and permeability,
groundwater ext-actlon will be a prolonged process. The length of time required
to extract groundwater Units the ImplementablHty of this option.
The exposure pathway: of direct contact and 1ngest1on for soil and groundwater
are eliminated through source control (removal and disposal of 18,300 yd3 of
contaminated soil) and offslte or management of migration measures (removal and
treatment of 760 million gallons of contaminated groundwater). All 'contaminants
will be removed to background levels. Because 1t entails the greatest amount
of off- site hauling, this alternative presents the greatest possibility of
human exposure during hauling. No post-closure Institutional restrictions will
be necessary.
Of the final alternatives evaluated, this has the highest cost (total estimated
capital cost $8,145,000 and present worth cost $72,020,000). The greatest
portion of this capital cost 1s associated with transportation and dlsoosal of
the contaminated materials ($5,934,000).
Alternative 2A
This alternative consists of construction of a multimedia RCRA compliant
cap over the contaminated portions of the site, and extraction and on-s1te
groundwater treatment using granular activated carbon (GAC) . This alternative
comply with appllcabla and relevant standards.
The groundwater extraction system for this alternative 1s the same as for
Alternative 1A. Contaminated groundwater will be pumped to a sump and then
through a series of columns packed with GAC. Water leaving the bottom of
the last column would flow by gravity to an offslte drainage ditch.
Following building demolition and disposal, offslte contaminated soil adjacent
to the Henfleld property and contaminated sediment 1n the dralnageways will
be excavated and consolidated on the site to fill the voids left by removal
of the buildings. The site will be compacted and graded (both properties) to
promote runoff from the finished cap, and to provide clearance so the edge of
the four foot thick cap 1s approximately level with the surrounding ground
surface. Site closure Involves fencing the capped areas, setting land use
restrictions on the properties, and Installing post-closure monitoring wells.
Capping contaminated soil 1n accordance with RCRA standards minimizes the
potential for direct exposure. The cap will last Indefinitely 1f properly
maintained. However, contaminants would still be present for possible future
release to groundwater. Carbon adsorption can effectively remove all the
organic contaminants of concern found 1n groundwater at the Old Mill site.
Contaminants are removed from the environment and are destroyed 1n the process
of carbon regeneration.
-------
The exposure pathway of direct contact and Ingestfon for soil and groundwater
will be decreased by this alternative. The groundwater quality will not be
restored to background or 10"^ levels, and the source of contamination and
possible leaching of contaminants Into the groundwater remains Indefinitely.
Because of the low transmlsslvity and yield of this aquifer, flushing occurs
slowly. Infiltration through the cap and horizontal flow through the contami-
nated soil will slowly leach contaminants Indefinitely. The groundwater
seasonally rises to the ground surface and comes 1n contact with the contaminated
soil. This causes leachate production from the unsaturated zone.
The present worth cost of this alternative 1s $3,375,000.
Alternative 2D
This alternative consists of removal and off-site disposal 1n a RCRA compliant
facility of 95 percent of the contaminant mass 1n the soil, and extraction and
on-s1te groundwater treatment using GAC. This alternative will comply with
applicable and relevant federal standards.
The groundwater extraction and treatment system 1s the same as for Alternative
2A.
This option requires removal of 75 percent less soil as that removed In the
complete soil removal alternative (4,300 yd3), but this would effectively
remove the majority of contaminant mass 1n the soil. The 5 percent contaminant
mass remaining 1n the soil will produce no Impact on groundwater cleanup during
the extraction period, and 1s representative of background or 10"^ carcinogenic
risk levels for soil Ingestfon.
The exposure pathway of direct contact and 1ngest1on will be greatly reduced by
this alternative. Removal of 95% of the soil contamination will effectively
prevent exposure to hazardous material at the site.
The present worth cost of this alternative 1s $4,440,000.
Alternative 2F
This alternative consists of excavation and on-s1te containment of 95 percent of
the contaminant mass 1n the soil, and extraction and on-site groundwater treat-
ment using GAC. This alternative complies with applicable and relevant standards.
The groundwater extraction end treatment system Is the same as for Alternative
2A.
This option requires the same soil excavation as Alternative 2D. The difference
1s that the soil will be fully contained 1n a landfill which will be constructed
on the site (Kraus property). The landfill will be constructed to meet RCRA
criteria Including double-lined bottoms and sides, a double-!eachate collection
system and a multimedia cap. Collected leachate will be treated «n-s1te using
the GAC system. Site closure Involves fence construction around the landfill,
Implementation of land use restrictions, and Installation of monitoring wells.
-------
On-s1te landfilllng prevents the spread of and exposure to hazardous materials.
The double liner and cap effectively contain contaminated materials. However,
the presence of a Class 2 (groundwater currently used or potentially available
for drinking water or other beneficial use) aquifer may limit the feasibility of
locating such a landfill. Since the groundwater table seasonally rises to the
ground surface, the Integrity and effectiveness of an on-site landfill may
become questionable. In addition, it 1s not recommended that a landfill be
located 1n an area of fractured bedrock. The bedrock in the vicinity of the
site 1s known to be fractured.
The present worth cost of this alternative 1s $4,050,000.
Alternative 3D
This alternative consists of removal and on-site containment of all contaminated
soil, and extraction and on-site grourdwater treatment using GAC. This alternative
exceeds all applicable and relevant standards.
This alternative is the same as Alternative 2F except that 100 percent rather
than 95 percent of the soil is removed and contained on the Kraus property.
The present worth cost of this alternative 1s $6,850,000.
Alternative 4D
This alternative consists of construction of a permeable cap over the contaminated
portions of the site, and extraction and on-site groundwater treatment. Imple-
mentation of this alternative will meet the goals of CERCLA, but may not comply
with applicable and relevant standards.
The environmental and public health aspects of this alternative are the same as
Alternative 2A except that the cap does not reduce infiltration Into the soil.
This results in a greater Infiltration rate and subsequently greater leachate
produced to enter the groundwater. The groundwater must be extracted for over
700 years in order to restore groundwater quality to 10~6 levels for consti-
tuents of concern, and the source of contamination remains Indefinitely.
The present worth cost of this alternative 1s $3,290,000.
Alternative 5
This alternative Includes construction of a site fence, and Installation of a
groundwater monitoring system and 1s considered a limited action alternative.
Total fencing 1s estimated to be 1,400 linear feet. Migration of groundwater
will be monitored. The rate and direction of migration will be determined,
and an extensive pollutant fate analysis will be performed to determine the
potential for adversely affecting receptors.
This alternative will temporarily minimize the direct contact threat. The
contaminated groundwater will continue to migrate.
The present worth cost of this alternative 1s $390,000.
-------
Alternative 6
Under this alternative no further remedial actions will be taken at the site.
The threats to public health and the environment will remain.
COMMUNITY RELATIONS
There has been considerable public Interest 1n the Old Mill site throughout
the RI/FS. Several public meetings have been held, and there have been
numerous letters and phone calls related to the site. Generally, the meetings
have drawn about 50-75 people (Rock Creek has a population of about 650) and
have lasted about three hours, with most of the time devoted to questions and
answers. Media coverage has been 1n the county papers and on the
local radio station.
The most Intense concern has been expressed by the Rock Creek Hazardous waste
Committee. Three members (one 1s also a member of the town council) have
generated the majority of Inquiries, although other residents and local offfdals
have occasionally Inquired about the status of the RI/FS or about specific
technical Issues. The committee also directs numerous Inquiries to the county
health department, the county disaster services office, and the local office of
the U.S. Congressional Representative.
Many Issues of concern have evolved during the RI/FS, however, the ouallty of
local drinking water has been and continues to be an Issue of primary concern.
In addition, many people have expressed frustration with the length
of time required for the RI/FS.
Specifically, some residents have requested that Immediate actions be taken
to restrict access to the entire site, that the on-s1te buildings be demolished,
that a tank on-s1te be removed (the site owner has since removed the tank), and
that the site receive "no less than total cleanup." The last request was
expressed as a demand for U.S. EPA action. Many people have also expressed
concern about potential for future migration of contamination.
Many of these concerns were expressed durlnq the cubllc consent period for the
RI/FS, and have been addressed by the U.S. F.PA 1n the "Responsiveness Summary".
The public comment period was extended to last over 4-1/2 weeks due to the
high level of citizen concern and Involvement. The citizens appear to stm
believe that this period was Inadequate and Indications are such that the community
does not feel that the recommended cleanup will be adequate.
CONSISTENCY WITH OTHER ENVIRONMENTAL LAWS
It 1s the recommendation of this document that the technical aspects of the
remedial alternative Implemented at the Old Mill site be consistent with other
applicable and relevant environmental laws. Other environmental laws which
may be applicable or relevant to the remedial- alternatives evaluated
1n the FS are the Resource Conservation and Recovery Act (RCRA), the Clean
Water Act, the Safe Drinking Water Act and the National Environmental Policy
Act (NEPA).
-------
10
The provisions of RCRA applicable to remediation at Old Mill would be the 40
CFR Part 264 technical standards for closure, and the Subpart F, Groundwater
Protection standards. RCRA requires that contaminated soil either be removed
to background or other standard protective of human health and environment
(closure as a storage unit by removal), or capped (closure In place as a landfill).
The capping alternatives evaluated In the FS are consistent with those actions
which would be taken during "closure" of a RCRA land disposal facility. The
alternatives which fully contain the contaminated soil on-site are consistent with
those actions necessary to build a new hazardous waste landfill, and to close such
a landfill. The complete soil removal alternative evaluated 1n the FS 1<
consistent with those actions which would be taken during closure of a RCRA storage
facility. The 95% removal alternative evaluated 1n the FS 1s also consistent
with those actions which would be taken during closure of a RCRA storage facility,
because even though all hazardous waste residues will not have been removed,
they will have been removed to levels adequate to protect public health and the
environment.
It has been determined that removal of 100 percent of the soil contaminant mass
would constitute removal to background levels and that removal of 95 percent
of the contaminant mass would constitute removal to levels adeauate to protect
public health and the environment. With the 95 percent removal option, for the
volatile compounds, the average concentrations remalninq are below the 10-6
carcinogenic risk value for soil 1ngest1on and contact but above background values.
For the base/neutral (3/N) compounds, the average concentrations remaining are
within the range of the 10-* to 10"^ carcinogenic risk levels depending on the
compound. Background concentration 1n the near vicinity of the site (e.g.
adjacent railroad bed) also fall within this range (1.1-1.7 mg/kg). For example,
for Benzo(a)Pyrene, a R/N compound of concern, the average concentration remaining
1n the soil will be at background levels. This level 1s greater than the ID-'5
risk level for soil 1ngest1on. Although contamination will be removed to
background, some risk remains for this compound. Benzo(a)Pyrene 1s an Immobile
compound and thus will not readily leach Into the groundwater.
From a transport based approach, the 5 percent of contamination remaining 1n
the son 1s not expected to cmse any dlscernable change 1n the groundwater
quality during the first 30 years of operation. Overall, from both a risk
and contaminant transport based approach, the levels remaining may be considered
adequate to protect public heath and the environment.
The groundwater protection standards of RCRA will be applicable to the level
of groundwater cleanup to be attained by a groundwater extraction system.
40 CFR Section 264.94 states that the concentration of a hazardous constituent
must not exceed the background level of that constituent 1n the groundwater, or
an alternate concentration limit (ACL) for that constituent which will not pose
a substantial present or potential hazard to human health or the environment as
long as that ACL 1s not exceeded. The hazardous constituents of concern are
those hazardous substances which were detected 1n the groundwater and soils at
the site during the RI. Although a variety of organlcs were found 1n the ground-
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11
water, the compounds trfchloroethene and tetrachloroethene are the constituents
of concern because Qf the ootentlal cardnogenlcity and the high concentrations.
From the Ieachate/so1l model In the FS, 1t 1s estimated that Benzo(a)Pyrene will
slowly leach from the soil Into the groundwater over a very long period of
time (5,000 years) and still not have exceeded levels of concern for drinking
water. Any low levels of B/M compounds that may be 1n the groundwater will be
removed by treatment using Granular Activated Carbon. Some low levels of other
B/N compounds were found In the groundwater both upgradlent of and on the Kraus
property, Indicating a source other than the Kraus site for these compounds.
It 1s proposed that the contaminant plume be contained by pumping and be treated to
a risk bassd "target" ACL of 10-5 excess cancer risk value. It 1s estimated that
this concentration can be attained 1n the aaulfer after 30 years of extraction
and treatment. Subsequent to this 30 year period, 1t 1s estimated that contaminant
concentrations will eventually attenuate to the soil and disperse to levels
that do not exceed 10-5 excess cancer risk levels. Institutional constraints on
aquifer use will be necessary until the groundwater has reached 10-6 levels.
The U.S. EPA has established that 10-- 1s an acceptable level for groundwater
remediation. This level Is considered an acceptable level for human drinking
water consumption. Under certain circumstances, levels other than 10-6 can
be considered target ACLs. At the Old Mill site, reaching 10-5 levels 1s
cost and time prohibitive. It 1s estimated that with complete source removal,
to reach 10-6 levels will take about 90 years. For any alternative with
less than complete removal, the time Increases. The groundwater plume has
migrated a short distance offsite (225 feet downgradlent of the site).
Transport modeling of the groundwater plume through the aquifer at the Old Mill
site has Indicated that, between the site and a short distance downgradlent
(1/4 to l/Z mils), 1f the plume (extraction snd treatment to 10-* level) were
allowed to migrate, the concentration In the plume may exceed 10-6 values for
about 100 years. After that time, at all places 1n the aquifer downgradlent from
the site, the aquifer would not be adversely affected by site activities.
Aquifer restrictions will protect all potential future users until acceptable
levels have been restored over the affected area. Although Initially the
levels of contaminants 1n the groundwater will be greater than 10-6, by means of
attenuation and dispersion, acceptable (10-6) levels will eventually not be
exceeded anywhere In the aquifer. Therefore, the proposed extraction and treatment
scenario (10-5) {s considered to be equally and adequately protective of human
health and the environment. Since full documentation of the aquifer characteristics
has not been obtained, the effectiveness of this extraction and treatment
system will be confirmed after operational performance data has been evaluated.
At that time the actual determination of an ACL will be made. It 1s estimated
that two to five years of operational performance data will be required to make
such a determination.
Any discharge of extracted groundwater at the site to the offsite dralnageway
will comply with substantive requirements of the Clean Water Act. A National
Pollution Discharge Elimination System (NPDES) permit will be Issued by and to
the State o* Ohio. The provisions of the NPDES permit will be established
by the Ohio EPA and U.S. EPA. During construction, care will be taken to avoid
stormwater runoff from the site.
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12
Under the Safe Drinking Water Act, Maximum Contaminant Levels for tetrachloroe-
thene and trichloroethene will soon be proposed 1n the Federal Register.
Depending on the results of this proposal, these levels may be met 1n the
groundwater.
This alternative meets NEPA functional equivalency. The necessary and appropriate
Investigation and analysis of environmental factors as they specifically relate
to the Old Mill site and the recommended alternative were considered and evaluated
1n the RI/FS. In addition, an opportunity for public comment on environmental
Issues was provided.
COMPARISON OF ALTERNATIVES
Using.the Information presented 1n Table 1?, the relative advantages and
disadvantages of each resulting alternative are compared 1n order to recommend
a "cost-effective alternative" as defined 1n the HCP.
Since the no action (Alternative 6) and limited action (Alternative 7) alternatives
do not adequately remediate present and future groundwater and soil contamination,
and do not address the human health concerns of direct contact or 1ngest1on of
contaminated groundwater or soil, these alternatives are not recommended for
Implementation at the site.
The present worth cost of Alternative 1A (100 percent contaminant removal)
1s more than an order of magnitude-greater (16 times) than Alternative 20
(95 percent contaminant removal). Implementation of either of these alternatives
will achieve similar environmental benefits (groundwater remediation, soil
removal). Contaminated soil removal and both offslte and onslte groundwater
treatment will remove contamination from the site and reduce exposure risks.
The time required to meet target groundwater cleanup levels of 10"6 1s approximately
the same for these alternatives. Therefore, Alternative 1A 1s not recommended,
because 1t would not be cost-effective.
Alternatives 2F and 3D differ only 1n the amount of soil contaminants contained
In an onslte landfill, 95 percent 1n Alternative 2F and 100 percent 1n Alternative
3D. As discussed earlier, the 95 percent removal effectively removes most of
the contaminant mass In the soil to levels adequate to protect public health
and the environment and requires removing only 25 percent as much son as 1s
necessitated In the complete soil removal alternative. Alternative 2F 1s more
cost-effective (similar environmental protection and benefits at lower cost)
than Alternative 3D. Therefore, Alternative 3D 1s not recommended.
Alternatives 2A and 40 will prevent direct exposure to contaminated soil
through construction of a cap. The multimedia cap required by Alternative 2A
1s more effective at reducing Infiltration and leachate production Into the
groundwater than 1s the cap required by Alternative 40. The greater Infiltration
rate of the clay cap required by Alternative 40 results 1n an Increase 1n
groundwater contaminant concentration during the Initial years of groundwater
extraction. Although the present worth costs for the alternatives are
similar, the environmental benefits, as measured by the leachate production
during the Initial operating years of Alternative 2A are greater than for
Alternative 40. Therefore, Alternative 40 1s not recommended for Implementation
at the site.
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13
Three alternatives remain for comparison. These are:
0 2A—Multimedia cap, groundwater extraction with onslte GAC adsorption
treatment.
0 2D--95-percent contaminant removal, disposal in offsite RCRA-11censed
landfill, groundwater extraction with onslte GAC adsorption treatment
0 2F—95-percent contaminant removal, disposal in onslte RCRA-Hcensed landfill
(to.be built on the Kraus property), groundwater extraction with onslte
GAC adsorption treatment.
Alternative 2A will minimize the human contact exposure, and decrease the
concentration of contaminants in the groundwater plume. The groundwater will
not be restored to background or 10~6 levels because the source of contamination
(contaminated soil) remains onslte, and slow leaching of contaminants Into the
groundwater will continue indefinitely. The contaminant plume will need to be
contained and treated by operating and maintaining an active groundwater
extraction system far into th-e future (hundreds of years). The reliability
and Implementability of maintaining such a system Into the Indefinite future
are less than If the source of contamination 1s removed. Much of the contamination
is adsorbed to the soil in the saturated zone (aquifer structure). Low transmissivity
of the aquifer results in a slow rate of flushing. Even if a cap were placed on
the site, a slow rate of Infiltration would occur. Also, since the water table
seasonally rises to the ground surface, contaminants.are leached slowly into
the groundwater. Therefore, both horizontal and vertical infiltration through
the contaminated soil would occur at this site. Since the other remaining
alternatives will eventually achieve a more effective level of groundwater
cleanup and greater public health benefits, and since the reliability of this
alternative is questionable because of the high water table and because of the
Indefinite containment and treatment time, this alternative, which does not far
exceed the cost of the other remaining alternatives, is not recommended for
Implementation at the site.
Implementation of Alternatives 20 and 2F involves groundwater treatment and
removal or onslte containment of soil (95 percent of the contaminant mass).
The present worth cost of Alternative 20, soil removal, is slightly higher than
Alternative 2F, soil containment ($4,440,000 versus $4,050,000).
The environmental benefit as measured by groundwater remediation 1s the same
for both assembled alternatives. The environmental benefit gained by removing
the soil contamination from the site exceeds the benefit of containing the
contaminated soil in an onslte landfill because there remains the possibility for
release of contaminants at the site. If the contaminated soil 1s removed
from the site, the possibility of exposure to the local community 1s eliminated
at the site. If an onslte landfill 1s created, permanent institutional constraints
will be needed at the site. The aquifer 1n the area of the site 1s presently
being used for drinking water. It 1s considered a Class II, current use aquifer.
Citing requirements discourage location of a landfill above this type of aquifer.
Citing requirements also discourage locating above fractured bedrock. The
shale 1n the area of the site 1s known to be fractured. Therefore, the long
term reliability of removal Is greater than that of on-site containment.
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14
Therefore, since the environmental, institutional, and public health and welfare
benefits of Alternative 20 are greater than those of Alternative 2F, and since
the cost to implement either is essentially the same, Alternative 2D Is recommended
as the cost-effective remedial alternative for implementation at the site.
RECOMMENDED ALTERNATIVE
It 1s recommended that FS Alternative 20 be selected as the cost-effective
remedial alternative in accordance with Section 300.68 of the National Contingency
Plan (NCP). This alternative 1s not the lowest cost alternative which provides
a minimally adequate remedy, but it 1s the cost-effective alternative which
adequately protects public health and the environment from the risks of further
exposure to contaminated soil and groundwater at the site. This alternative
substantially complies with all other environmental laws, and has a total
present worth cost of $4,440,000.
DESCRIPTION OF THE PROPOSED REMEDY
The recommended alternative Involves offsite disposal of 4,300 yd^ of con-
taminated soil and sediment; groundwater containment, extraction, and treatment
using direct contact GAC; and the opportunity for connection of downgradient
residences within 0.5 mile of the site to the currently available public water
supply. Two downgradient residences have been Identified. Although these
wells are not presently affected by contamination from the site, as a precautionary
measure 1t 1s recommended that these wells be taken out of service and that the
residences be connected to the public water supply. This alternative
will remove .the source of contamination, and will reduce contaminant concentrations
1n groundwater to acceptable levels.
OFF-SITE REMEDIAL ACTION (FOR THE PROPOSED REMEDY)
(1) Groundwater Extraction System
A number of groundwater extraction wells will be placed downgradient
from the site in order to capture the plume before further migration
from the site. Each well will have a pumping rate of 1 gallon per
minute to provide a capture zone of approximately 100 feet, and
groundwater velocity of approximately 20 feet per year.
According to the analysis performed on the groundwater system, and
as demonstrated in Figures 6 and 7, meeting a cleanup goal of 10~&
carcinogenic risk levels 1n groundwater 1s time prohibitive (about 100
years). In these figures, the line which corresponds to this alternative
1$ the 95 percent contaminant removal. Thus, a cleanup risk based
"target" concentration of 10*5 1s proposed. It Is estimated that
the average concentration of contaminants 1n the plume can be reduced
to this level within 30 years. The extraction wells will be placed to
contain the contamination at concentrations greater than the 10"*>
carcinogenic risk level isopleth.
The analysis 1n the FS, considering groundwater flow rates, flow-path
lengths, porewater velocities, and retaf.ation coefficients of the
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1000
Careinogtnicitv Protection P!»k Uvti • 10
No Rtmoval. RCRA Cap
CtrtfnoQtnidrv Protaction Risk Laval" 10
18% Contaminant Rtmoval.. ft£flA C*P
Carcinoganicltv Protaction fil»k Ltva! • 10
96% Contaminant Rtmoval.
88% Contaminant Rtmoval
98% Conteminam Rtmoval
0.1
200 300
TIME (Ynn)
400
500
NOTI: Tha analytit of taacn
tiort invotom animation of racnarga ram.
tna quantity of eomnninanu gvailaota for mtfiine, concantrniom of t»oa» conaminarm
in wanar parcoiatino. ttirougn tna ynaaturatad xona. ratat of contaminant contribution to
i andfO^ounovjatar attraction ratat> Cctimataa of tnis
kind art tanaux and limriad in accufaty bacauta of tna uncartaintiat atioclataa witri
lamailt data, tita cnaractahiation. and tna davaiopmamai naturt of mt teianca: ho»»avar,
tnay ara ajvaamiad Nara av a practical tool for aBaming tna raiati^m impacn aaiociattd
•itn laria^i ramadial <
FIGURE G
IMPACT OF TARGET CLEANUP CRITERIA ON
ESTIMATED DURATIONS OF GROUNDWATER
EXTRACTION FOR TRICHLOROETHENE
MENFIELO PROPERTY
OLD MILL SITE
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Carcinooanicitv Protection Rii* Ltvtl • 10
U% Contaminant Rwnoval
Carci.toganicitv Protection
Ritk Laval- 10-6
No Removal. RCRAC*0
88% Contaminant Removal.
Careinoeanicitv Protection RUk Level • 10*
98% Contaminant Romovtl,
99% Conttmirunt Rtmevat
Total Contaminant
0.01
100
200 300
TIME (Yaan)
400
500
' interaction i*
i ntimation o( i'«cHaig« ran*.
tfta imanrtm of eon\*nn**u aoailaMa tar Macnin*. eanontraiiont o( tfioaa eontamtnarm
in waaar parvoiatina, titro««ti tfta unMiuratad xona. ratat of oomartunam eantnbution to
Mia fraundwatar or Mturatad tana and groundwatar ••traction njtav (itimatn o« tnit
kind am tantama and limitad in accuracy bacauta of ma uncar'aintia* aiaociatad witn
Mrnpta data. «ta cnaraciaruation. and trw drvaiopmamal natura of tna icianca: howiavar.
tfwy art piaaamad nara *a a practical tod for aManina. tna ralatraa hnpactt aitociatad
FIGURE 7
IMPACT OF TARGET CLEANUP CRITERIA
ON ESTIMATED DURATIONS OF
GROUNDWATER EXTRACTION FOR
TETRACHLOROETHENE
H6NFI6LO PROPERTY
OLD MILL SITE
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15
compounds detected at the Old Mill site, estimates that extraction of
VOCs for approximately 30 years will be required to achieve to 10~5
cleanup levels 1n the entire plume. Any contamination present at lower
levels when this cleanup level 1s attained will be allowed to migrate
and disperse, and will naturally attenuate to the soil. Three contaminant
transport models were used to estimate the fate of allowing the plume
(10'5) to migrate. It Is estimated that, 1/4 to 1/2 mile downgradlent
from the site, after the extraction system 1s shut down, the contamination
levels will not exceed the 10'6 carcinogenic risk level anywhere In
the aquifer after about 100 years. Institutional constraints will need
to be placed on the contaminated aquifer plume, and a short distance
downgradlent from the plume, until 1t 1s determined, through monitoring,
that such constraints are no longer necessary.
(11) Groundwater Treatment Systam
The treatment system for contaminated groundwa-ter, prior to discharge to
the offslte drainage ditch, consists of a series of GAC columns. Removal
efficiency would be sufficient to meet discharge limitations set by the
NPDES requirements. Limitations will call for an effluent which meets
Water Quality Standards after the effluent mixes with existing flow (low
flow Is zero during parts of the year). The NPDES permit will be applied
for and Issued by the State of Ohio.
(11i) Aquifer Restrictions and Public Water Supply
Aquifer use restrictions will be required as long as concentrations 1n
the plume are above 10~6 carcinogenic risk levels. Because of unce^taint.
Involved 1n extraction and containment of groundwater, those residences
within 0.5 miles downgradlent from the site, which may potentially be
affected, will be given the opportunity to be connected to the currently
available public water supply. These actions will adequately protect
all current receptors. Since a comparatively small cost is involved in
this particular aspect of the alternative ($12,000), and since the cost
of a continuous monitoring program of these private wells would exceed
the cost for a permanent connection, this action 1s both cost-effective
and protective of public health..
SOURCE CONTROL REMEDIAL ACTION
(1) Building Demolition
The buildings at the site are known to have been used for storage of
hazardous wastes. In addition, sampling and visual observations have
Identified a number of spills of hazardous substances inside the
buildings. It 1s recommended that contaminated portions (assumed to
be those portions which have come Into contact with contaminated soil)
of the buildings be demolished, and that contaminated waste materials
be transported off-site to a U.S. EPA approved hazardous waste disposal
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16
facility. Uncontaminated waste materials will be transported to a
sanitary landfill. Sampling to confirm contamination will occur prior
to or during the demolition of the buildings. The selection of an
off-site RCRA facility will be made in coordination with the RCRA
regional office where the facility 1s located.
(11) Soil Removal
Soil contamination at the Old Mill site has been documented surficially
over the majority of the site, and throughout portions of the unsaturated
zone to the water table at a 5 foot depth. The results of the RI indicate
that contamination of soils with base/neutral (B/N) and volatile organic
compound (VOC) priority pollutants exists primarily within the top 2 feet
of the soil profile. Selected areas of soil removal from the site would
result in approximately 95 percent removal of both B/N and VOC contamination.
This removal would result 1n residual concentrations that constitute levels
which are adequate to protect public health and the environment in the
soils. B/N compounds will be removed to U.S. EPA contract laboratory
detection limits or background, and volatiles will be removed to 10-°
carcinogenic risk levels for ingestion of contaminated soil. The estimated
areas of soil removal are shown on Figures 8 and 9.
The leachate-groundwater analyses presented in Appendix G and Chapter 5
of the FS Indicate that this soil removal scenario will substantially
reduce the total amount of contaminants transported from soils (unsaturated
zone) to the aquifer (saturated zone). This removal is also necessary to
eventually restore the aquifer to 10~6 carcinogenic risk levels. Limited
land use restrictions will be necessary to protect the monitoring and treatment
system, and to restrict aquifer use 1n the plume. It will not be necessary
to cap the site because the site will be closed as a storage unit [40 CFR
Part 264 (k)] and the contamination will have been removed to levels
adequate to protect public health and the environment. Confirmatlonal
soil testing will be done during the remedial action to assure that adequate
cleanup levels are reached.
This remedial action will require use of an offsite land disposal facility.
No hazardous substances from the Old Mill site will be taken to an offsite
RCRA facility unless 1t Is 1n compliance with the U.S. EPA "Procedures for
Planning and Implementing Off-site Repsonse Actions". These procedures
preclude use of a facility that has significant RCRA violations or other
environmental conditions that affect the satisfactory operation of the
facility. Among other things, the procedures also require that the
facility have an applicable permit or Interim status and have been Inspected
within six months prior to disposal. The land disposal facility will
meet the minimum RCRA technical requirements. Three facilities within
the geographical area (300 mile radius) of the site were considered for
disposal in developing cost estimates.
OPERATION AND MAINTENANCE (O&M)
Each alternative was evaluated for O&M as shown in Tables 4 through 11. The O&M
costs were estimated on an annual basis over 30 years. The O&M for the recommended
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AREAS
(ABANDONED RAILROAD ROUTE!
AREA OF POSSIBLE
SOIL REMOVAL
KEY
\ ] AREAS Ot KHOPOSEP SOIL REMOVAL
BOUND AH Y OF PROPOSED CAPPING AND FENCED AREA
0 30 60
SCALE IN FEET
(PROPERTY BOUNDARIES ARE APPROXIMATE.I
5 feet of soil removed in areas 8 and 10.
2 fe~* of soil removed in area 9
1 f soil removal in areas 2, 5, 6. 7, 11, 13, and '
FIGURE 8
AREAS DELINEATED FOR SOIL AND
LEACHATE GROUNDWATER ANALYSIS
HENF'IELO PROPERTY
OLD MILL SITE
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\
X
(PROPERTY BOUNDARIES ARE APPROXIMATE)
KEY
MARSHY AREA
STOCKPILES OF RAILROAD BALLAST
, KB A US PROPERTY ORAINAGEWAY
APPROXIMATE AREA Of PROPOSED
SOIL REMOVAL AND/OR CAPPING
——PROPOSED FENCED AREA
5-3
FIGURE 9
LOCATION OF SOIL REMOVAL
AND/OR CAPPING
KRAUSPROPERTY
OLD MILL SITE
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17
alternative will require an offslte groundwater monitoring program consistent
with RCRA closure regulations, and extraction and treatment of contaminated
groundwater. The 04M period will last until such time as either applicable or
relevant standards or ACLs are met. The period for 0*M 1s expected to last for
30 years. The State of Ohio will assume responsibility for long term O&M of
the remedial action. The U.S. EPA will enter Into a State Superfund Contract
with the State of Ohio to formalize this agreement.
SCHEDULE
MILESTONES DATE
Approve Remedial Action (ROD) 7-31-85
Approve REM II Design Workplan 7-31-85
Amend REM II Work Assignment 7-31-85
Award IAG (design assistance) 7.31.95
Regin design 8-01-85
Complete design 9-OQ-85
Award Superfund State Contract (construction) 9-13-85
Award IAG (construction) 9-13-85
FUTURE ACTIONS
Uncertainty exists as to the contaminant removal efficiency physically
attainable In the aquifer at the Old Mill site. Although our final remedial
goal 1s to restore the groundwater to safe (10-5) levels, the actual performance
of the extraction system and the natural attenuation capacity of the aquifer
must be monitored before an Alternate Concentration Level (ACL) can be set. A
groundwater protection standard will be set with the goal of protecting the
public health and the environment both now and 1n the future. Two major
variables for setting a final cleanup standard are data adequacy and treatment
reliability. Although the analytical data for the groundwater at the Old Mill
site adequately defines the areal extent of contamination, Information on the
physical characteristics of the aquifer system 1s limited. This limits
the assessment of the treatment reliability of the extraction system.
It 1s predicted that the extraction time will be prolonged due to the low yield
of the aquifer (30 years to attain JO'5 levels). It Is further predicted that,
1f the treated plume (10~5) 1s allowed to migrate and naturally attenuate,
after about 100 years, 10"° levels will not be exceeded In the aquifer. Thus, 1t is
expected that after 130 years, the groundwater will be restored to acceptable
(10-6) levels. Therefore, the actual ACL determination will be deferred until
operational data 1s available to make this determination. The U.S. EPA and Ohio
EPA will monitor the performance of the extraction system. This will provide a
greater certainty that the groundwater management objectives can be met within
a reasonable period of time. After the performance of the extraction system is
more fully assessed, and after consultation with the Ohio EPA, an actual ACL
will be set. Therefore, this remedy will be considered an Interim remedy
until the ACL has been set. The State of Ohio will be responsible for assuring
that Institutional constraints will be honored for that portion of the aquifer
which 1s contaminated until 10~6 levels are not exceeded, and for long term
monitoring of the aquifer and 0AM of the extraction and treatment system.
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18
Specifics of the monitoring frequency and the mechanism for controlling ground-
water use in contaminated portions of the aquifer will be defined in the O&M
plan which will be developed during design and may be refined as operational
data becomes available.
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