United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R07-90/038
September 1990
Superfund
Record of Decision:
Missouri Electric Works, MO
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.
50272-101
REPORT DOCUMENTATION 11. REPORT NO. 12.
PAGE EPA/ROD/R07-90/038
.. Title and Subtitle
SUPERFUND RECORD OF DECISION
Missouri Electric Works, MO
First Remedial Action - Final
7. Aulhor(.)
3. Recipienfa Acce..lon No.
5. Report Dlte
09/28/90
&.
8. Perfonning Org.nlzatlon Rep\. No.
8. P8rfonnlng Org.lnlzatlon 1181118 .nd Add....
10. ProjectITllklWork Unit No.
11. ContreC1(C) or Grlnt(G) No.
(C)
(G)
12. ~orIng Org.nlz8llon 1181118 .nd Addre..
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report' Period Co-.cl
800/000
1..
15. Suppfemenl8ry No..
18. Abe...ct (Umft: 200 word.)
The 6.4-acre Missouri Electric Works (MEW) site is an electrical equipment sales,
service, and remanufacturing operation in Cape Girardeau, Missouri. Intermittent onsite
runoff channels flow into Cape LaCroix Creek located 0.7 miles east of the site, which
enters the Mississippi River, 1.1 miles to the southeast. A wetland area is located 700
feet south of the site. Since 1953, MEW has recycled materials from old electrical
equipment, including the reuse of filtered transformer oil. More than 16,000
transformers have been repaired or scrapped, and approximately 28,000 gallons of
transformer oil received onsite were never recycled. The MEW property, as well as
adjacent properties, have been contaminated with PCBs as the result of inadequate
storage and handling of transformers and PCB-contaminated transformer oils. In
addition, spills and disposal of industrial spent solvents occurred onsite affecting
ground water underlying the site. In 1984, preliminary State and EPA investigations
found leaking drums of transformer oil onsite and PCB levels in soil of up to 21,000
mg/kg. Based on this, in 1984, the State required removal of approximately 5,000
gallons of drummed waste oil. EPA conducted investigations from 1985 to 1987 that
(See Attached Page)
17. Document Analyal. L D88cr1peo18
Record of Decision - Missouri Electric Works, MO
First Remedial Action - Final
Contaminated Media: soil, s~diment, gw
Key Contaminants: VOCs (benzene, PCE, TCE)., other organics (PCBs)
b. Identifler8JOpen-Ended Tenne
c. casA T1 FI8fdIGroup
18. AVlllabilty SI8tement
18. Security ClI.. (Thl. Report)
None
20. SecurIty ClI.. (Thl. Pege)
None
21. No. of Plgee
86
22. Prfce
I
(SM A~Z38.18)
5H In.fnK:lio~ on RBverM
272 (4-11)
(Formerly NTI~)
Depe_t of Commerce
-------
EPA/ROD/R07-90/038
Missouri Electric Works, MO
First Remedial Action - Final
Abstract (Continued)
revealed onsite PCB contamination in the soil at levels of up to 58,000 mg/kg. Offsite
migration of PCBs also was detected during these investigations. In 1988, the EPA
required MEW to notify the public of site contamination, limit exposure to employees and
the public, and minimize movement of PCB-contaminated soil offsite from runoff and
erosion. In 1989, barriers were installed across runoff channels to intercept
contaminated runoff. This Record of Decision (ROD) addresses both contaminated soil and
sediment removal, as well as the treatment of affected ground water. The primary
contaminants of concern affecting the soil, sediment, and ground water are VOCs
including benzene, PCE, and TCE; and organics including PCBs.
The selected remedial action for this site includes excavating PCB-contaminated soil and
sediment and treating these by incineration onsite; placing exhaust gases through
flue-gas coolers and particulate removal systems; removing acid gases in-situ;
backfilling with residual materials, based on leachability test results; constructing a
soil cover over the site; pumping and treatment of ground water with filtration and
treatment via air stripping with subsequent carbon adsorption; discharging the treated
water offsite to a surface drainage ditch between the site and the wetlands or to a
publicly owned treatment works (POTW). The estimated present worth cost for this
remedial action is $9,130,000, which included an estimated annual O&M cost of $64,010
for 15 years.
PERFORMANCE STANDARDS OR GOALS: Contaminant levels for soil and sediment after
treatment will represent an excess upper bound lifetime cancer risk of 2 x 1~5 .
Cleanup levels for ground water will be 10-5 and cleanup levels will meet the TSCA PCB
Spill Cleanup POlicy, State water quality standards and Federal MCLs for VOCs.
Chemical-specific goals include TCE 5 ug/l (MCL) for ground water, PCB 10 mg/kg (TSCA)
for soil to a depth of 4 feet, and PCB 100 mg/kg (TSCA) for soil below a 4-foot depth.
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RECORD OP DECISION
MISSOURI ELECTRIC WORKS SITE
CAPE GIRARDEAU, MISSOURI
Prepared By:
U.S. Environmental Protection Aqency
ReqioD VII
Kansas City, Kansas
September 1990
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RECORD OP DECISION
DECLARATION
MISSOURI ELECTRIC WORKS SITE
CAPE GIRARDEAU, MISSOURI
prepared by:
U.S. Environmental Protection Aqency
Reqion VII
Kansas City, Kansas
September 1990
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RECORD OF DECISION
DECLARATION
SITE NAME AND LOCATION
Missouri Electric Works Site
Cape Girardeau, Missouri
STATEMENT OF PURPOSE
This decision document presents the selected remedial action
for the Missouri Electric Works Site, located in Cape Girardeau,
Missouri. This decision was developed in accordance with the
Comprehensive Environmental Response, Compensation, and Liability
Act of 1980 (CERCLA), 42 U.S.C. 9601 et seq. as amended by the
Superfund Amendments and Reauthorization Act of 1986 (SARA), and
to the extent practicable the National Contingency Plan (NCP);
40 CFR Part 300 (1990). The Regional Administrator has been
delegated the authority to approve this Record of Decision.
The State of Missouri has concurred with the selected remedy
and determined that the selected remedy is consistent with
Missouri laws and regulations.
STATEMENT OF BASIS
This decision is based on the administrative record compiled
for the Site which was developed in accordance with section 113(k)
of CERCLA, 42 U.S.C. 9613 (k). The Administrative Record is
available for public review at the Cape Girardeau Public Library
located at 711 North Clark Street, Cape Girardeau, Missouri and at
the Environmental Protection Agency (EPA) Regional Office located
at 726 Minnesota Avenue, Kansas City, Kansas.
ASSESSMENT Ql THE SITE
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), present a current or
potential threat to public health, welfare, or the environment.
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DESCRIPTION OF THE SELECTED REMEDY
The selected remedy for the Site is a comprehensive approach
for complete remediation of the principal threats posed by the
Si1:e. This approach will address the polychlorinated biphenyl
(PCB) contamination of the soils and sediments and the volatile
or~ranic compound (VOC) contamination of the ground water.
The major components of the selected remedy include:
Soil/sediment contamination
Excavate all soils and sediments with PCB concentra-
tions greater than 10 parts per million (ppm) to a
depth of 4 feet and soils below that depth with PCB
concentrations greater than 100 ppm;
Incinerate onsite the excavated PCB-contaminated
soils and sediments;
Monitor at least daily the emissions from the incin-
erator, both ash and gases; and,
Backfill the excavated areas with the ash and clean
soil.
Ground Water Contamination
Install six to ten extraction wells;
Extract ground water and store it in a tank onsitei
Process the stored water through an air-stripping
tower;
Process the vapor-phase after air-stripping through
an activated carbon adsorption unit, discharge the
treated water to the surface or to the publicly
owned treatment works (POTW): and,
Monitor 'quarterly the effectiveness of the ground
water treatment system.
STA'ruTORY DETERMINATIONS
The selected remedy is protective of human health and the
environment, complies with Federal and state requirements that are
applicable or relevant and appropriate (ARARs) to this remedial
action, and is cost-effective. The remedy satisfies the statutory
preference for remedies that employ treatment and reduce the
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toxicity, mobility, or volume as a principal element and utilize
permanent solutions and alternative treatment technologies to the
maximum extent practicable.
This remedy will not result in hazardous substances
remaining onsite above health-based levels. However, because
hazardous substances will be left onsite at levels that will
require limited uses of and restricted exposure to the Site, a
review of the remedial actions will be made no less often than
every five years after initiation of the remedial action.
L24i;l{~
Regional Administrator
U.S. EPA, Region VII
9. Z-B--Cj'c;
Date
-------
69 '27/99 H14?
~o :-tHI-WRSiE l'!Gi
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J0H:.., ~~HClOPT
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(j TRACY MEHAN III
0.-..
ST"'1: Uf MISSOlJlJ
DEPARTMENT OF NATURAL RESOURCES
.
omc£ Of THF. DlRF.CTOR
'.0. lox 17'
Jdl'crson CJly. MO 65102
)14''''1-4422
01\111 (VI DI Iftr".,.,
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U'~IIOII of (ical.~ 111\1 ull\l ~"'"
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UniiIW/\ oll'.V'4cl. lire".....:."
.....11."."" III"",,,,,...,,,
&epte~b.r 24, 1990
Mr. Mcrr1. Ray
Regional ~dmini8tr.tor
u. s. !nvironm=n~&l Protection
A~e~cy, ~e9ion V!I
;2~ Minnesota ~venue
~ansas C1:y, KS 56101
Dee.r ~r. ~ay:
The Misso~ri Dep~rtment o~ Natural ~e50ur08i hac r.vi8VQ~ ~he
Prcposad Plar. for the M~&souri !lectric works &uperfu~d ~itQ in
~ape Girarde&u, ~1!sour1. The Dcpart~ent concu~s with the
nreferre~ alternative of on-sl~e 1ncineratior. of tho
ccntar.1nated soils and air-st=lpplng of the oon~~~~natcd
gtoundwater baaed on the 1nrc=ma~ion available.
!f yo~ ~ave any que8ti?n~ =8~&rdlng this mat~er. please de no~
hesitate to contact me.
ver tru!y Y_~;lrs. .:
DEfART~~)9FN~TUR~l RE~ URCES
IJ/ j 'I" /1 'Ai ~I 'J, //
I,. flL{,ljYl. 'L..~j (~~,
G. Tracy Mehal'/I :
Director V
aTM. r;h
~~;
Mr. RODC:t Morby, USIPA
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RECORD OF DECISION
DECISION SUMMARY
MISSOURI ELECTRIC WORKS SITE
CAPE GIRARDEAU, MISSOURI
prepared By:
u.S. Environmental Protection Agency
Region VII
Kansas City, Kansas
September 1990
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1.0
2.0
2.1
2.2
2.3
2.4
3.0
4.0
5.0
6.0
7.0
8.0
8.1
8.1.1
8.1.2
8.1.3
8.1.4
8.1.5
8.1.6
MISSOURI ELECTRIC WORKS SITE
RECORD OF DECISION
DECISION SUMMARY
TABLE OF CONTENTS
Page
SITE NAME, LOCATION, AND
DESCRIPTION....................1
SITE HISTORY AND ENFORCEMENT ACTIVITIES.................1
5 i te Hi story. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Site Investigations.....................................4
Enforcement Activities..................................7
National Priorities List Status......................... 9
COMMUNITY
PARTICIPATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
SCOPE AND ROLE OF RESPONSE ACTION......................10
SITE CHARACTERISTICS SUMMARY...........................10
SUMMARY OF SITE RISKS.................................. 10
REMEDIAL GOALS........................ . . . . . . . . . . . . . . . . . 13
DESCRIPTION OF ALTERNATIVES............................ 23
Soil/Sediment Remedial
Alternatives....................24
No Action Alternative
( 8M -1) . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Limited Action Alternative (SM-2)......................24
Asphalt Cap Alternative (SM-4).........................25
Offsite Landfill Alternative (SM-6)....................25
Onsite Stabilization/Fixation
Alternative (SM-7).................................... .26
Solvent Extraction Alternative (SM-8)..................27
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8.1.7
8.1.8
8.2
8.2.1
8.2.2
8.2.3
8.2.4
8.2.5
8.2.6
8.2.7
9.0
9.1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
9.9
TABLE OF CONTENTS (continued)
Page
In Situ vitrification Alternative (SM-10)............29
Onsite Incineration Alternative (SM-11)..............29
Ground Water Remedial
Alternatives...................32
No Action Alternative
( GM -1) . . . 0 . . . . . . . . . . . . . . . . . . . . . 3 2
Limited Action Alternative (GM-2)....................32
Extraction and Discharge to Surface Waters
Al ternative (GM-3)................................... 33
Extraction with Discharge to Publicly Owned
Treatment Works (POTW) Alternative (GM-4)............33
Air-stripping Alternative (GM-5) .....................35
Liquid Phase Carbon Adsorption
Alternative (GM-6) ...................................35
Ultraviolet Catalyzed Oxidation
Alternative (GM-7)................................... 37
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES......37
Overall Protection of Human Health
and the Environment.................................. 37
Compliance with ARARS............................... .41
Long-Term Effectiveness and Permanence...............42
Reduction of Toxicity, MObility, or Volume...........43
Short-Term Effectiveness.............................44
Implementability.................................... .44
Cost. . . . . . . . . . . . . . . . . . . . . . . -. . . . . . . . . . . . . . . . . . . . . . . . . . 45
State Acceptance.....................................47
Communi ty Acceptance................................. 47
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10.0
10.1
10.:2
11. 0
12.0
TABLE OF CONTENTS (continued)
THE SELECTED REMEDY
Soils/Sediments....
Page
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
C;~()lll1ci ~Clt:E!~... .....................................51
STATUTORY DETERMINATIONS. ...........................54
DOCUMENTATION OF SIGNIFICANT CHANGES. ...............54
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Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
LIST OF FIGURES
Page
Missouri Electric Works
Site. . . . . . . . . . . . . . . . . . . . . . 2
Location
of Wetland Area..........................3
Extent of PCB Contamination at
Concentrations of 10 ppm or greater...............6
Extent of Ground Water contaminant Plume..........8
PCB contamination of Missouri Electric
Works Property...................................ll
Typical Solvent Extraction Process...............28
In situ Vitrification Process....................30
Schematic of Rotary Kiln Process.................31
(Onsite Incineration)
Conceptual Layout of Extraction
Wells........... .34
Schematic of Air-stripper........................36
Flow Diagram of PCB-Contaminated Soils-
Remedial Action..................................49
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Table 1
Table 2
Table 3
Table 4
Table 5
Table 6
Table 7
Table 8
Table 9
Table 10
Table 11
LIST OF TABLES
Page
Summary of PCB Exposure Risks for Children
Current and Future Use.........................14
Summary of PCB Exposure Risks for Adults
Current Use.................................... 15
Summary of PCB Exposure Risks for Adults
Future Us e. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Summary of PCB Exposure Risks for Children
Increased Cancer Risks.........................17
Summary of PCB Exposure Risks for Adults
Increased Cancer Risks--Current Use............18
Summary of PCB Exposure Risks for Adults
Increased Cancer Risks--Future Use.............19
Summary of Exposure Risks, Ingestion of VOC
contaminated Ground Water, for Adults..........20
Summary of Increased Cancer Risks, Ingestion
of VOC contaminated Ground Water, for Adults...21
Summary of Increased Cancer Risks, Ingestion
of VOC contaminated Ground Water,
for Children...."...............................22
Evaluation of Remedial Alternatives
PCB-Contaminated Soils.........................38
Evaluation of Remedial Alternatives
VOC-Contaminated Ground Water..................39
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Missouri Electric Works Site
Record Of Decision
Figure 1 - Missouri
Electric Works Site
2
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RECORD OF DECISION
DECISION SUMMARY
1.0
SITE NAME. LOCATION. AND DESCRIPTION
Missouri Electric Works, Inc., is located on a 6.4-acre
tract adjacent to u.s. Highway 61 (South Kingshighway) in a
predominately commercial/industrial area of Cape Girardeau,
Missouri. The Missouri Electric Works (MEW) site includes all
areas that have been identified as having PCB contamination. The
approximate extent of the MEW Site is presented in Figure 1.
The MEW site is situated approximately 1.6 miles west of the
Mississippi River in the hills along the valley wall just west of
the Mississippi River flood plain. Intermittent runoff channels
emar.ate from the north, south and east boundaries of the MEW
property and eventually drain into the Cape LaCroix Creek located
0.7 miles east of the Site. The Cape LaCroix Creek flows 1.1
miles to the southeast where it enters the Mississippi River.
The MEW property is bounded on the north by retail and warehouse
properties, on the south by a residence, commercial storage and a
construction company, and on the east by a warehouse. A wetland
has been identified approximately 700 feet south of ~he MEW
property. Figure 2 indicates the approximate location of the
wetland in relation to the MEW Site and the city of Cape
Girardeau.
2.0
SITE HISTORY AND ENFORCEMENT ACTIVITIES
2.1
site Historv
Missouri Electric Works, Inc., sells, serVices, and remanu-
factures transformers, electric motors, and electrical equipment
controls. During past operations, Missouri Electric Works, Inc.,
reportedly recycled materials from old units, selling copper wire
and reusing the dielectric fluids from the transformers. The
salvaged transformer oil was filtered through Fuller's earth for
reuse. An estimated 90 percent of the oil was recycled.
Missouri Electric.Works, Inc., has been at its present loca-
tion since 1953. According to business records obtained from
Missouri Electric Works, Inc., more than 16,000 transformers have
been repaired or scrapped at the Site during this time. The total
amount of transformer oil that was not recycled during this period
is estimated to be 28,000 gallons. In 1984, approximately 5,000
gallons of waste oil, in drums, was removed by a contractor.
1
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Industrial solvents were used to clean the electrical equip-
ment being repaired or serviced. Solvents were reused until they
were no longer effective. Spills and disposal of spent solvents
apparently occurred on the MEW property.
The MEW plant and general office occupy a building located
on the west end of the property. To the east of the building and
concrete pad is a gravel area of approximately 150 by 120 feet
used for transformer storage. Portions of the site are littered
with various objects including old transformers, empty drums, old
pallets and trash. The MEW property and adjacent properties have
been found to be contaminated with'polychlorinated biphenyls
(PCBs), specifically Aroclor 1260. This PCB contamination is
apparently the result of past handling and storage procedures of
PCB-containing transformer fluids.
2.2
site Investiqations
The Missouri Department of Natural Resources (MDNR) inspected
the MEW facility in October 1984 and discovered 102 55-gallon
drums containing transformer oil that were being stored on the MEW
property. Some of the drums were leaking. A sample of the oil-
stained soil was obtained by MDNR for analysis and found to con-
tain 110 parts per million (ppm) polychlorinated biphenyls (PCBs).
A sample of oil-stained surface water was taken by MDNR. The
analytical results for the water sample indicated a PCB
concentration of 110 micrograms per liter (ug/l) or. parts per
billion (ppb).
An inspection by the Environmental Protection Agency (EPA)
during November 1984, pursuant to the Toxic Substances Control Act
(TSCA), found that MEW handling and storage procedures for oils
containing or contaminated with PCBs did not conform to the regu-
lations. Two soil samples and one sample of stored oil were
obtained. PCBs were detected in the soil samples at concentra-
tions of 310 and 21,000 milligrams per kilogram (mg/kg) or parts
per million (ppm). The oil contained 1,200 ppm PCBs.
Additional and more extensive site investigations of the MEW
facility and adjacent properties were performed by EPA contractors
between October 1985 and June 1987. These investigations
indicated that PCB contamination in surface soils at the facility
was extensive (with PCB concentrations as high as 58,000 ppm);
that shallow subsurface soils at the Site were contaminated to a
lesser extent; that offsite migration of PCB-contaminated soils
had occurred along drainage paths; that measurable levels of PCBs
were present onsite and on nearby offsite building walls; and
that measurable concentrations of airborne PCBs were present.
One round of sampling from onsite monitoring wells indicated that
shallow ground water contained low concentrations of PCBs;
4
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.
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NOIltT)o1
Missouri Electric Works Site
Record Of Decision
Figure 2 - Location
Of Wetland Area
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LEGEND
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-~ :oNTOUI'
UND-~
IN1DVA&, . 2 flIT
Missouri Electric Works Site
Record Of Decision
Figure 3 - Extent Of PCB
Contamination at Concentra-
tions of .10 ppm or greater
I
'00
'*'
200
JOG
-------
however, later sampling of the wells by EPA and more detailed
analysis during the Remedial Investigation (RI) did not detect
PCBs in the ground water and it was concluded that the earlier
results were probably the result of sampling errors. These
investigations, as well as other investigations are summarized in
more detail in the RI Report.
EPA obtained wipe samples of the exterior of several
buildings located in the vicinity of MEW during August 1989.
Analytical data from these samples indicated that no PCBs had
migrated to the buildings west of Highway 61.
The Missouri Electric Works Steering Committee (MEWSC), a
group of potentially responsible parties for the Site, conducted a
RemE~dial Investigation (RI) pursuant to an Administrative Order on
Consent issued by EPA. The field activities were conducted from
Sept:ember 1989 to March 1990. The findings of these activities
are summarized below:
1.0 Soils
PCBs adsorbed onto the near-surface soils have been trans-
ported onto surrounding properties primarily via storm water
runoff. This contamination is located primarily along drain-
age pathways with the levels decreasing with greater distance
from MEW. The highest levels of PCBs observed in any offsite
sample (2,030 ppm) was found in a drainage channel at the
boundary between the MEW property and the Morrill property.
Geostatistical modeling of the data collected during the RI
was used to determine the areal extent of PCB contamination
on the site and surrounding areas. The total area of surface
soils and sediment with PCB concentrations of 10 ppm or
greater is approximately 295,000 square feet or 6.8 acres
(excluding areas covered by paving and structures). The
limits of the 10 ppm isoconcentration contour are shown in
Figure 3. It is estimated that the area contaminated with
PCB concentrations of 500 ppm or greater is over four acres.
The upper bound 95 percentile confidence level of the arith-
metic mean is approximately 5,000 ppm for all samples taken
at the Site.
PCB contamination was found at depth in the transformer
:storage and debris burial areas. Additionally, Volatile
Organic Compound (VOC) contamination was detected in soils
down to 2.5 feet below the ground surface south and east of
'the MEW building, the transformer storage area and the debris
burial area.
5
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2.
Ground Water
PCBs were not detected in any of the ground water samples
obtained during Phases I and II of the RI. Water samples
obtained during Phase III were not tested for PCBs. VOCs,
particularly 1,1-dichloroethane, trans-1,2-dichloroethene,
chlorobenzene, and trichloroethene, were detected in
Monitoring Well Nos. 3 and 5 at concentrations in the part
per billion (ppb) range. The highest concentration of total
VOCs detected was 320 ppb. Analytical data from additional
sampling showed that VOC-contaminated ground water has
migrated beyond the MEW property boundaries in one of the two
offsite wells (see Figure 4).
Ground water in the vicinity of the Site is apparently
flowing to the east, northeast, and southeast from the Site,
as the MEW property is the "high" point in the immediate
area. These ground water flow directions are based on
limited observations.
Regional geologic and hydrogeologic information in the pos-
session of the Missouri Division of Geology and Land Survey
(DGLS) indicates that the limestone bedrock extends to a
depth of about 1,000 feet without a significant shale layer
being present. This means that there is not a barrier or
confining layer present to prevent the downward migration of
contaminaticn in the bedrock aquifer once the contamination
reaches ground water. Some of the VOC contaminants are known
to be "sinkers", i.e., they are heavier than water and tend
to sink through water to a confining layer.
No users of the upper portions of the bedrock aquifer were
identified. This does not mean that users do not exist.
Users of lower portions of the bedrock aquifer have been
identified.
3.
Surface Water and Adiacent Wetland Area
Surface water samples were collected in the drainage ditch
along Wilson Road and in the wetland area immediately south
of Wilson Road. No PCBs were detected in any of those
samples.
2.3
Enforcement Activities
An Administrative Order was issued to Missouri Electric
Works, Inc., by EPA pursuant to ~106 of CERCLA on August 2, 1988.
This Order required Missouri Electric Works, Inc., to perform
several response actions, specifically: to notify the public of
the site contamination: minimize the exposure of the public and
7
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IA.
LIe::
NO~TM
MEW
GO
(STlUA'IION PlUME Of'
TOTAl VOlA11l.E ORGANICS
(SUMMATION Of VOlA11lE ORGANICS IN £ACH WEll -
PHASE III R£SUl TS)
Missouri Electric Works Site I
Record Of Decision
Figure 4 - Extent Of Ground
Water Contaminant Plume
-------
employees to PCB-contaminated dust, soil or sediment; and
minimize the amount of PCB-contaminated soil migrating from the
property in surface water runoff. EPA installed barriers across
drainageways during 1989 to more effectively intercept PCB-
contaminated runoff. Also as mentioned above, EPA entered into
an Administrative Order on Consent with the MEWSC, whereby the
group agreed to perform the Remedial Investigation/Feasibility
Study (RI/FS).
2.4
National Priorities List status
The Missouri Electric Works Site was proposed for listing on
the National Priorities List (NPL) in June 1989. The MEW site was
listed on the NPL on February 21, 1990.
3.0
COMMUNITY PARTICIPATION
EPA and the Missouri Department of Health held meetings with
adjacent property owners and other interested citizens in Cape
Girardeau, Missouri on July 11 and 12, 1989. The purpose of these
meetings was to discuss the site conditions and the health risks
that the Site represented to the general public. EPA staff par-
ticipated in two local Cape Girardeau, Missouri radio talk shows
during July 1989; interested citizens were able to "call-in" and
ask questions of the EPA staff concerning the Missouri Electric
Works Site and the related activities.
The Administrative Record was placed in the Cape Girardeau
Public Library on August 11, 1989. A public meeting was held in
Cape Girardeau on September 19, 1989 to inform the public of the
details of the ongoing remedial investigation and to identify
possible remedial alternatives that would be considered during the
feasibility study. A second public meeting was held on June 11,
1990 to inform the public of the remedial investigation findings
and to again identify the remedial alternatives that would be
considered during the feasibility study. Fact sheets, identifying
significant site activities, were mailed to everyone on the Site
mailing list (which included local media, officials and PRPs)
during June, August, and November 1989 and March, May and
July 1990.
The RI/FS Reports and Proposed Plan for the Missouri Electric
Works Site were released to the public on August 18, 1990. These
three documents were included in the addendum to the administra-
tive record located in the EPA Record Center, Region VII and at
the Cape Girardeau, Missouri Public Library. Notice of the
availability of these documents was published in the News Guardian
and the Southeast Missourian on August 19, 1990. A public
comment period was held from August 19 to september 17, 1990. In
addition, a public hearing was held on August 30, 1990. At this
meeting, representatives from the EPA, the Missouri Department of
9
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Natural Resources (MDNR), the Missouri Department of Health
(MDOH) and the Agency for Toxic Substances and Disease Registry
(ATSDR) were available to answer questions about problems at the
sitE~ and the remedial alternatives under consideration. EPA's
response to the comments received during this comment period is
embc)died in the Responsiveness Summary.
4.0
SCOPE AND ROLE OF RESPONSE ACTION
The remedial action to be performed at the Missouri Electric
Wor}cs Site, has been divided into two parts: the first part
addresses the contaminated soils. The second part addresses the
con1:aminated ground water. The contaminated soils pose a threat,
current or potential, to human health and the environment due to
the risks of possible ingestion, inhalation or dermal contact with
the soils. The contaminated ground water poses a threat, current
or potential, to human health and the environment because of
possible future ingestion of drinking water from wells that con-
tain contaminants above health-based levels. The purpose of the
response actions is to prevent and/or minimize current or future
exposure to the contaminated soils and ground water. These
actions are expected to be the final response actions for the MEW
site.
5.0
SITE CHARACTERISTICS SUMMARY
Nine contaminants of concern were detected at the site during
the investigations. These contaminants include polychlorinated
biphenyls (PCBs) and volatile organic compounds (VOCs); specifi-
cally, methylene chloride, trichloroethane, trans-l,2-dichloroe-
thene, chlorobenzene, l,l-dichloroethane, trichloroethene, tetra-
chloroethene, and benzene. The presence of these contaminants is
the result of past handling, disposal, and storage practices at
the site.
Approximately 75 percent of the surface soils on the Missouri
Electric Works property were found to be contaminated with PCBs at
concentrations of 10 ppm or greater (see Figure 5). PCBs adsorbed
ontci the soils have migrated, primarily via storm water runoff,
onto surrounding properties. This contamination is generally
located along drainage pathways with the concentrations decreasing
with greater distance from MEW. The highest concentration of PCBs
obsE!rved in any offsite sample (2,030 ppm) was found in a drainage
channel at the boundary between the MEW property and the Morrill
property located to the south.
6.0
SUMMARY OF SITE RISKS
A Baseline Risk Assessment of the MEW site was performed by
the MEWSC to assess the risks posed to human health by the PCB and
VOC-'contaminated 50i15 and sediments and the VOC contaminated
10
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..-
..-
LE GEND
~
NO--TM
-
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)..
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iii
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'DO
JOel
Missouri Electric Works Site
Record Of Decision
.
D
~
PAC IICA
MEA t11 "ACE
IGIL. 8C8 c:GNC:DI1b 'ftON
~1D 'ItWI '0 ...
~~ :oN1tIUIt
UNES-COITDUIt
IN1Dv,,", . 2 PIr
Figure 5 -PCB Contamination
of Missouri Electric Works
Property
-------
ground water. The compounds of concern and the media in which
they were detected are presented in tabular form below.
Detected Compounds
PCBs
Methylene Chloride
Trichloroethane
Trans 1,2-dichloroethene
Chlorobenzene
1,1 Dichloroethane
Trichloroethene
Tetrachloroethene
Benzene
Environmental Media
Soil, Sediment, Air
Soil
Soil
Ground water
Soil, Ground water
Ground water
Ground water
Ground water
Ground water
Pathways through which populations could potentially become
expc)sed were evaluated. These pathways include: 1) ingestion of
cont:aminated soils; 2) dermal (skin) contact with contaminated
soils; 3) inhalation of contaminated soil particles and vapors;
and 4) ingestion of contaminated ground water.
Incremental lifetime cancer risks and a measure of the
potential for noncarcinogenic adverse health effects were
estimated for each population in each exposure scenario. For
carc:inogenic compounds, risks were estimated by multiplying the
estimated exposure dose by the cancer potency factor of each
contaminant. The product of these two values is an estimate of
the incremental cancer risk.
For noncarcinogenic compounds, a Hazard Index (HI) value was
estimated. This value is a ratio between the estimated exposure
dOSE! and the reference dose (RfD) which represents the amount of
toxicant that is unlikely to cause adverse health effects.
Generally, if the HI is less than one, the predicted exposure
dOSE! is not expected to cause harmful noncarcinogenic human
health effects. Where the HI exceeds one, the potential to cause
advE~rse noncarcinogenic human health effects increases as the
HI increases.
Due to the potential additive effects of ingestion,
inha.lation and dermal contact to contaminants via different
pathways, exposure routes for soil were identified. There are
thre~e routes at which populations could potentially be exposed
via one or a combination of scenar.ios. These exposure routes
are: 1) occupational (site workers); 2) recreational users of
the Site, both adults and children; and 3) residential
popu.lations, both adults and children. These exposure scenarios
were evaluated for current and future uses of the site. The
futu.re use scenario included ingestion of contaminated ground
water as an additional exposure pathway.
12
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For purposes of the Risk Assessment, it was assumed that no
remedial action would be performed at the site in order to
evaluate the possible future risks posed by the contamination.
The risks posed by the soil contamination at the Site are
summarized in Tables 1 to 6.
No current exposure risk was evaluated for ground water. \
Information indicates that there are currently no users of the
upper portion of the ground water. No contamination was detected
in the ground water samples obtained from the onsite drinking
water well. Risks to human health were evaluated assuming that
drinking water wells would be installed in the contaminated zone
of the bedrock aquifer in the future, for human consumption.
Tables 7 to 9 summarize the risks associated with ingestion of
contaminated ground water.
The analyses performed indicated that the MEW Site currently
presents an unacceptable risk to human health and the environment
for all of the exposure scenarios. with respect to the ground
water, available information on the regional geologic conditions
indicates there is not a barrier in the limestone bedrock to
prevent downward contaminant migration in the ground water. The
depth to the first barrier is estimated to be approximately 1,000
feet. Because the potential for exposure is greater due to
increased ground water usage at such depths, the contamination
must be addressed.
7.0
REMEDIAL GOALS
EPA's national goal for the Superfund program is to select
remedies that will be protective of human health and the
environment, that will maintain protection over time and that
will minimize untreated waste. In establishing remedial goals
for the MEW Site, EPA considered applicable or relevant and
appropriate requirements (ARARs) specific to the contaminants of
concern; the Risk Assessment; Maximum contaminant Levels (MCLs)
and Maximum contaminant Level Goals (MCLGs) established under the
Safe Drinking Water Act; and EPA guidance and policy, specifically
the TSCA PCB Spill Cleanup POlicy, 40 C.F.R. Part 761 (A complete
list of ARARs for the selected remedy is included as Appendix A) .
For soil contamination, EPA considers a cleanup level of
10 ppm PCBs to a depth of four feet and 100 ppm in soils below
four feet to be protective of hum~n health and the environment.
With these cleanup levels, the geometric mean of analytical data
of samples obtained outside the area to be excavated is estimated
to be 6 ppm. This residual contamination concentration, after
cleanup, represents gn excess upper bound lifetime cancer risk on
the order of 2 x 10-. These cleanup levels are consistent with
the TSCA PCB Spill Cleanup Policy.
13
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TABLE ~ -- SUMMARY OF PCB EXPOSURE RISKS POR CHILDREN
MISSOURI ELECTRIC WORKS SITE
Current Use == Hazard Index 1HIl
Recreational
Exposure Point Worst Case Most Probable Case
Ing(~stion 2.47 0.00356
Dermal 8.51 0.0123
Inhalation 0.000140 0.0000349
10.980140 0.0158949
Total
Residential
Exposure Point Worst Case Most Probable Case
IngE~stion 91. 5 0.132
Dermal 315 0.454
Inhalation 0.0620 0.0155
406.5620 0.6015
Total
Future Use == Hazard Index
Recreational
Exposure Point Worst Case Most Probable Case
Ingestion 6.24 0.00898
Dermal 10.4 0.015
Inhalation 0.000167 0.0000419
Total 16.640167 0.0240219
Residential
Exposure Point Worst Case Most Probable Case
Ingestion 189 0.272
Dermal 315 0.0454
Inhalation 0.0620 0.0155
Total 504.0620 0.3329
14
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TABLE A --
SUMMARY OF PCB EXPOSURE RISKS FOR ADULTS
MISSOURI ELECTRIC WORKS SITE
Current Use-- Hazard Index
Recreational
Exposure Point
Worst Case
Most Probable Case
Ingestion
Dermal
Inhalation
0.0548
3.08
0.000131
0.0000791
0.00443
0.0000326
Total
3.134931
0.0045417
Residential
Exposure Point
Worst Case Most Probable Case
0.284 0.000410
16.0 0.0230
0.0580 0.0145
16.342 0.03791
Ingestion
Dermal
Inhalation
Total
Occupational
Exposure Point
Ingestion
Dermal
Inhalation
Worst Case Most Probable Case
0.365 0.000527
20.5 0.0295
0.0193 0.00483
20.8843 0.034857
Total
15
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TABLE ~ -- SUMMARY OF PCB EXPOSURE RISKS FOR ADULTS
MISSOURI ELECTRIC WORKS SITE
Future Use == Hazard Index
Rec:reational
Exposure Point
Ingestion
Dermal
Inhalation
Worst Case Most Probable Case
0.650 0.000938
3.76 0.00541
0.000157 0.0000392
4.410157 0.0063872
Total
Residential
Expc:)sure Point
Worst Case
Most Probable Case
IngE~stion
Dermal
Inhalation
20.3
114
0.0580
0.0293
0.164
0.0145
Total
134.358
0.2078
Occupational
Exposure Point
Worst Case Most Probable Case
20.3 0.0293
114 0.164
0.0193 0.00483
134.3193 0.19813
Ingestion
Dermal
Inhalation
Total
16
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TABLE ~ -- SUMMARY OF PCB EXPOSURE RISKS FOR CHILDREN
MISSOURI ELECTRIC WORKS SITE
Current Use == Increased Cancer Risks
Recreational
Exposure Point
Worst Case Most Probable Case
1X10-3 2X10:~
4XlO-3 4X10-8
6x10-8 2x10
5X10-3 4X10-3
Ingestion
Dermal
Inhalation
Total
Residential
Ingestion
Dermal
Inhalation
1X10-2
4X10-2
3XIO-5
5X10-2
2X10:~
4X10-6
7x10
4X10-2
Total
Future Use == Increased Cancer Risks
Recreational
Exposure Point
Worst Case
3XlO-3
5XlO-3
8X10-8
Most Probable Case
4XlO:~
7xlO
2XlO-8
Ingestion
Dermal
Inhalation
Total
8XlO-3
l.lXlO-5
Residential
Ingestion
Dermal
Inhalation
8XlO-2
1X10-1
3X10-5
1.8XlO-l
lXlO::
2X10-6
7xlO
3XlO-4
Total
17
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TABLE ~ -- SUMMARY OF PCB EXPOSURE RISKS FOR ADULTS
MISSOURI ELECTRIC WORKS SITE
Worst Case Most Probable Case
3xlO-5 4X10-8
lX10-3 2XIO::
6X10-8 lxlO
lxlO-3 2X10-6
Current Use == Increased Cancer Risks
Recre~tional
Exposure Point
Ingestion
Der:mal
Inh,alation
Total
Res:idential
Exposure Point
Worst Case
lxlO-4
7X10-3
3XIO-5
Ingestion
Dermal
Inhalation
Total
7.1X10-3
occupational
Exposure Point
Worst Case
2X10-4
9xlO-3
6XIO-6
Ingestion
Dennal
Inhalation
Total
9X10-3
18
Most Probable Case
2X10-7
lxlO-5
6XIO-6
1.6X10-5
Most Probable Case
2XIO:~
lxlO 6
~xlO-
1.2XIO-5
-------
TABLE
.t --
SUMMARY OF PCB EXPOSURE RISKS FOR ADULTS
MISSOURI ELECTRIC WORKS SITE
Future Use == Increased Cancer Risks
Recreational
Exposure Point
Worst Case
3XlO:~
2X10-8
7x10
Ingestion
Dermal
Inhalation
Total
2.3X10-3
Residential
Exposure Point
Worst Case
9X10-3
5xlO-2
3X10-5
Ingestion
Dermal
Inhalation
Total
5.9XlO-2
occupational
Exposure Point
Worst Case
6X10-3
4X10-2
6X10-6
Ingestion
Dermal
Inhalation
Total
4.6XlO-2
19
Most Probable Case
4X10-7
2X10-6
2X10-8
2.4X10-6
Most Probable Case
1X10-5
7XlO-5
6X10-6
8.6XlO-5
Most Probable Case
9X10-6
5XlO-5
2X10-6
6.lXlO-5
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TABLE 2 -- SUMMARY OF EXPOSURE RISKS FOR ADULTS
INGESTION OF VOC-CONTAMINATED GROUND WATER
MISSOURI ELECTRIC WORKS SITE
Fut\~ Use == Hazard Index
Residential
Cont:aminant
Trans 1,2-dichloroethene
Chlclrobenzene
1,1-dichloroethane
Trichloroethene
Tetrachloroethene
Benzene
Total
occupational
contaminant
Trans 1,2-dichloroethene
Chlorobenzene
1,1-dichloroethane
Trichloroethene
Tetrachloroethene
Benzene
Total
Worst Case
Most Probable
Case
0.055
0.240
0.0036
(1)
0.024
ill
0.011
0.0094
0.0078
(1)
0.0044
ill
0.3226
0.0326
Worst Case
Most Probable
Case
0.0275
0.120
0.0018
(1)
0.0120
ill
0.0055
0.0047
0.0039
(1)
0.0022
ill
0.1613
0.01613
(1) The Hazard Index cannot be calculated since an
acceptable dose has not been established.
20
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TABLE ~ -- SUMMARY OF EXPOSURE RISKS FOR ADULTS
INGESTION OF VOC-CONTAMINATED GROUND WATER
MISSOURI ELECTRIC WORKS SITE
Future Use == Increased Cancer Risk
Residential
contaminant
Worst Case
Most Probable
Case
Trans 1,2-dichloroethene
Chlorobenzene
1,1-dichloroethane
Trichloroethene
Tetrachloroethene
Benzene
(1 )
(1)
2X10:~
2x10
7X10:~
2x10
3X10-S
Total
occupational
(1)
( 1)
4X10-6
4X10-7
1X10-6
9X10-7
6X10-6
Contaminant
Worst Case
Most Probable
Case
Trans 1,2-dichloroethene
Chlorobenzene
1,1-dichloroethane
Trichloroethene
Tetrachloroethene
Benzene
(1)
(1)
7X10-6
8X10:~
3x10
7X10-7
1x10-5
Total
(1)
Incremental risk cannot be calculated since a
carcinogenic potency factor is not established.
21
(1)
(1)
1X10-6
1x10-7
5X10-7
3X10-7
2X10-6
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TABLE ~ -- SUMMARY OF EXPOSURE RISKS FOR CHILDREN
INGESTION OF VOC-CONTAMINATED GROUND WATER
MISSOURI ELECTRIC WORKS SITE
Future Use == Hazard Index
Res:LcSential
contaminant
Worst Case
Most Probable
Case
Trans 1,2-dichloroethene
Chl()robenzene
l,l-dichloroethane
TriGhloroethene
Tetrachloroethene
Ben2:ene
0.175
0.750
0.011
(1 )
0.076
III
Total
1. 012
Future Use == Increased Cancer Risk
Residential
0.0345
0.0295
0.0025
(1)
0.0140
III
0.0805
Contaminant
Worst Case
Most Probable
Case
Trans 1,2-dichloroethene
Chlorobenzene
1,1-dichloroethane
Trichloroethene
Tetrachloroethene
Benzene
(2)
(2)
9XIO-6
1XIO-6
3X10-66
6x10-
2X10-5
Total
(1)
The Hazard Index cannot be calculated since an
acceptable dose has not been established.
Incremental risk cannot be calculated since a
carcinogenic potency factor is not established.
(2)
22
(2)
(2)
2XIO:;
2XIO-7
6X10-6
3x10
6X10-6
-------
For ground water contamination, EPA has determined that a
cleanup level of 20 ppb for chlorobenzene, which has been
detected at levels up to 240 ppb, and 5 ppb for trichloroethene
(TCE) , which has been detected at levels up to 19 ppb, is ade-
quate to protect human health and the environment. The residual
contamination levels, after cleanup, represent an e~cess upper
bound life-time cancer risk on the order of 1 x 10-. These
cleanup levels comply with Missouri Water Quality standards and
the MCLs for those contaminants.
The cleanup lev~ls for the MEW site result in cancer risks
in excess of 1 x 10- , which is the point of departure for deter-
mining remediation goals. The cleanup levels for the Site have
been identified after considering the background levels of PCBs
in the environment and the technical impracticability of removing
PCBs below 10 ppm. Ground water cleanup levels were selected
based on the technical limits of remediation. Case studies for
ground water remediations have indicated that the effective
removal of contaminants from the ground water lessens as
contaminant concentrations decrease.
8.0
DESCRIPTION OF ALTERNATIVES
The MEWSC performed a Feasibility Study (FS) to develop and
evaluate alternatives for remediation of the contaminated soil and
ground water at the Site. The remedial alternatives developed and
evaluated in the FS are presented below. (Alternatives for
contaminated soil are identified with an 'iSM" prefix; ground water
alternatives are identified with a "GM" prefix. Identification
numbers match those presented in the FS.)
For Contaminated Soils:
Alternative SM-l
- No Action Alternative
Alternative SM-2
- Limited Action Alternative
Alternative SM-4
- Asphalt Cap
- Offsite Landfill
Alternative SM-6
Alternative SM-7
- Solidification/Fixation
Alternative SM-8
-. Solvent Extraction
Alternative SM-I0 - In-situ vitrification
Alternative SM-ll - Rotary Kiln Incineration
23
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For Ground Water Contamination:
Alternative GM-1
- No Action
Alternative GM-2
- Limited Action Alternative
Alternative GM-3
- Extraction with Discharge
to Surface Water
Alternative GM-4
- Extraction with Discharge
to POTW
Alternative GM-6
- Air-Stripping
- Liquid Phase Carbon Adsorption
Alternative GM-5
Alternative GM-7
- Ultraviolet Catalyzed
Oxidation
8.1
Soil/Sediment Remedial Alternatives
All PCB-contaminated soils with concentrations in excess of
10 ppm will be addressed during this remedial action. The volume
of PCB-contaminated soils and sediments to be addressed with this
remE!dial action is estimated to be 20,500 cubic yards. This
estimate is based on the RI and other investigations performed at
the Site.
8.1.1
No Action Alternative
(SM-l)
As set forth in the National Contingency Plan, 40 CFR Part
300 (NCP), a no action alternative must be considered in the
evaluation and selection of a remedial action for NPL sites. This
alternative would provide no treatment of the soils or ground
water, nor any engineering controls or institutional controls.
Current site conditions, migration routes, and exposures would
remain unchanged in the near- and long-term. Treatability tests
will not be required. No costs would be associated with this
remedy.
8.1.2
Limited Action Alternative (SH-2)
The Limited Action alternative for the MEW Site incorporates
physical and institutional controls to limit direct exposure to
the contaminated soils/sediments/waste, and provides for long-term
monitoring and maintenance of the Site. This alternative would
consist of: installation of a physical barrier around all onsite
and loffsite areas exhibiting surficial soil PCB concentrations of
10 ppm or greater; use of institutional controls to prohibit
disturbance of contaminated soils/sediments/waste and to restrict
use of the site to industrial purposes; and maintenance of the
24
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site including vegetative cover, perimeter fencing, and all other
appropriate support facilities. Treatability tests would not be
required. Monitoring and maintenance would continue for at least
30 years.
Estimated Time for Construction
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth cost
2 months
30 years
$65,000
$7,000
$140,325
8.1.3
Asphalt Cap Alternative (SK-4)
The alternative would involve consolidating the contaminated
soils and covering them with a low permeability asphalt cap. The
purpose of this cap would be to reduce the potential for migration
of contamination into the ground water, prevent direct contact
with the waste mass and reduce potential migration from storm
water and/or precipitation runoff. All contaminated soils from
offsite areas would be consolidated with soils from some onsite
areas to occupy approximately four acres located in the eastern
two-thirds of the MEW property. Rip-rap would be placed on the
side slopes of the property to minimize the potential for migra-
tion due to erosion. Heavy equipment would be used to construct
the cap, which would probably be constructed of asphalt. Treat-
ability tests would not be required. After construction, fences
would be erected around the MEW property, signs would be installed
and a monitoring/maintenance program initiated. Monitoring and
maintenance would continue for at least 30 years.
Estimated Time for Construction
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost
2 months
30 years
$825,000
$13,000
$950,000
8.1.4
Offsite Landfill Alternative (8M-a)
All soils contaminated with concentrations of PCBs of 10 pprn
or greater would be excavated to a depth of four feet; below that
depth, those areas with PCB concentrations in excess of 100 ppm
would be excavated. The excavated. material would be transported
offsite by truck to a TSCA-permitted chemical waste landfill. The
excavated areas would be backfilled, using clean material from
offsite borrow areas, and revegetated. The principal components
of this alternative would consist of identification of an EPA-
approved facility to accept the PCB-contaminated soils; excava-
tion and transportation of the contaminated soils; placement of
25
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thE~ contaminated soils in the selected facility~ restoration of
thE~ MEW site, including backfilling, compaction, and final grad-
ing for drainage; and revegetation of the MEW Site. Testing of
the excavated soils would be required to verify landfill
acceptance.
Estimated Time to Implement
Estimated capital Cost
Estimated Annual operation and
Maintenance Cost
Estimated Present Worth Cost
2 months
$10,900,000
$0
$10,900,000
NOTE: For soil alternatives SM-6, SM-7, SM-8, and SM-I0,
all soils contaminated with PCB concentrations of 10 ppm or
greater would be excavated to a depth of four feet; below
that depth soils containing PCBs in excess of 100 ppm would
be excavated. The excavated material would be stockpiled on
the MEW property in areas constructed to contain runoff and
the piles would be covered to minimize contaminant migration
due to wind erosion.
8.1.5
Onsite stabilization/Fixation Alternative (SM-7)
stabilization/Fixation is a treatment process which employs
additives to diminish the hazardous nature of materials
containing hazardous constituents by converting the waste into a
fo~n that immobilizes the hazardous constituents within a stable
matrix. stabilization processes typically involve mixing the
was1:e with chemical reagents to immobilize contaminants and
improve the physical properties of the waste. This process would
reduce the migration potential of the PCBs. Treatability tests
would be required to identify the most effective additives and the
optimum percentage and ratios of the additives. The excavated
soils would be processed and fed into a mixer (similar to a pug
mill) where the moisture content would be adjusted and a stabili-
zation/fixation agent added. Tight controls on mixture ratios
would be exercised. A high degree of quality control would be
required and exercised during the mixing and blending process.
An area on the MEW property would be excavated to create cells
with sufficient volume to receive the processed soils. The
processed soils would be transported to the excavated monolith
area, placed and compacted in the cells. A soil cover, thirty
(30) inches thick wou~d be constructed over the cells. The
cohesive nature (clayey) of the S~te soils could cause a problem
if additives are not effective in solidifying them or fixing the
cont.amination; treatability tests would be required. Institu-
tional controls would be required to restrict use of the MEW
property. The area would be fenced and signs installed. Long-
term monitoring would be initiated.
26
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Estimated Time for Construction
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual operation and
Maintenance Cost
Estimated Present Worth Cost
. 1 year
30 years
$4,300,000
$13,500
$4,400,000
8.1.6
Solvent Extraction Alternative (SM-B)
This alternative would employ a chemical separation process
utilizing one or more of a family of aliphatic amine or other
solvents. While the processes are designed to recover and recycle
solvents used for extraction, the fine-grained nature of the soils
at the MEW site may hinder recovery, resulting in some amount of
solvent remaining in treated soils. site soils may reduce the
effectiveness of the process thereby making it more difficult to
implement. The availability of the process equipment is
uncertain. Solvent extraction processes applied to soil con-
tamination are generally considered to be in a developmental/
demonstration state. Studies have shown the process to be capable
of 99+ percent removal of PCBs from a wide variety of sludges,
soils and sediments. Excavated soils would require processing
prior to treatment. The soils would be placed in a closed mixing
chamber where a chilled solvent would then be introduced. Mixing
would occur, the solids would be allowed to settle, and the sol-
vent would be pumped off. Additional solvent "charges" would be
added, as necessary, to attain cleanup standards (see Figure 6 for
a diagram of the process). Extracted PCBs would be collected,
stored and disposed offsite by incineration in accordance with
TSCA regulations. Residual water may be a byproduct of the
process. This water could require testing and additional' treat-
ment. Construction of a wastewater treatment plant to process
the residual water could be necessary. (The costs presented
below do not include those for a wastewater treatment plant.)
The excavated areas would be backfilled, using the treated soils
and covered with a clean soil cover.
A treatability study would be needed for this remedial action
alternative to evaluate its feasibility for the site conditions
and to evaluate the reaction time needed to achieve cleanup
levels.
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost
1 year
$6,400,000
$0
$6,400,000
27
-------
SCREENED
CON lAMINATED
SOil
COItRAI£
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00
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WASHER/
DRYER
DRY. WASUED SOLIDS
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ER
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Missouri Electric Works Site
Record Of Decision
Figure 6 - Typical Solvent
Extraction Process
-------
8.1.7
In-Situ Vitrification Alternative (SM-l0)
In-situ vitrification is a treatment process that uses an
electric current to heat soils to their melting point. Due to
the relatively shallow depth of contamination at the Site, con-
taminated soils would be excavated and placed in 12 to lS-foot
trenches for treatment. Electrodes would be placed into the soil
in the trenches and an electric current induced between the
electrodes. The current would heat the soils, causing them to
melt. The melting soils would cause a 20 to 40 percent reduction
in the volume of the soils being treated. This process has been
shown to destroy organic contaminants, i.e, PCBs, by pyrolyzing
them (see Figure 7). By-products of the pyrolysis migrate to the
surface and burn in the presence of oxygen. A specially designed
hood would be placed over the treatment area to collect gases
generated during the processing and maintain a controlled atmos-
phere in which the gases could burn. The gases in the hood would
be processed through various steps before being released into the
atmosphere. Treatability tests are likely to be needed.
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost
1 year
$11,200,000
$0
$11,200,000
8.1.8
Onsite Incineration Alternative (SM-ll)
The onsite incineration alternative provides an onsite
treatment process to manage PCB-contaminated soils from all onsite
and offsite areas. Rotary kiln incinerators (see Figure 8) are
probably the most common type of equipment used for mobile incin-
eration because they have been commercially proven, provide flexi-
bility in handling many types of materials and provide good
mixing and long residence times for solids. A trial burn would
be required to identify the residence time required to destroy
the PCB contamination.
The incineration operation would require approximately one
acre of space at the site. The contaminated soils would be
processed to obtain the proper particle size and then "fed" into
the lower end of the combustion chamber. Use of a high combustion
air velocity and circulating solids would result in a uniform
temperature around the combustion .loop resulting in rapid heating
of the materials and highly efficient combustion, thus eliminating
the need for an afterburner or secondary combustion of off-gases.
Thermal treatment would achieve a PCB-destruction efficiency of
99.9999 percent.
29
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Missouri Electric Works Site
Record Of Decision
Figure 7 - In-situ Vitrification
Process
3~
-------
I".J
....
8UI8IIII. ,. r. .',."
Missouri Electric Works Site
Record Of Decision
Figure 8 - Schematic Of
Rotary Kiln Process
(Onsite Incineration)
-------
Exhaust gases would be routed to air pollution control
devices consisting of flue-gas coolers and particulate removal
systems before being released to the atmosphere. Acid gases
would be removed in-situ. During operation, treated soil and ash
would be removed periodically and cooled.
After thermal treatment, the treated soils and ash would be
tested using, the Toxicity Characteristic Leaching Procedure
(TCLP) prior to their use as backfill for the excavated areas of
the site. After backfilling the excavated areas, a soil cover
would be constructed over the site and the Site would be
revegetated.
Estimated Time to Implement
Estimated capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost
1-2 years
$8,400,000
$0
$8,400,000
8.2
Ground Water Remedial Alternatives
Based on available data, it is estimated that the volume of
ground water that will require treatment is 1,000,000 gallons.
This figure is based on information gathered during the instal-
lation and sampling of the monitoring wells.
8.2.1
No Action Alternative (GM-l)
As set forth in the NCP, a no action alternative must be
considered in the evaluation and selection of a remedial action
for an NPL site. This alternative would provide no treatment of
ground water, no engineering controls or institutional controls.
Current Site conditions, migration routes and exposures would
remain unchanged in the near- and long-term. No costs would be
associated with this remedy.
8.2.2
Limited Action Alternative (GM-2)
This alternative would incorporate physical and institutional
controls to prevent or limit direct exposure to the contaminated
soils/sediments and ground water and would provide for monitoring
of the ground water contamination. Monitoring of the ground water
would be accomplished using an array of onsite and downgradient
wells designed to track the leading edge of the contamination
plume and quantify horizontal migration within the water bearing
unit. Analytical data gathered during the monitoring activities
would be evaluated to determine if additional remedial actions are
necessary. The monitoring would be continued until contaminant
levels in the ground water fall below the MCLs (it is assumed that
the monitoring would continue for 30 years).
32
-------
Estimated Time for Construction
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost (30
years, 10%)
2 months
30 years
$73,500
$36,000
$375,000
For Alternatives GM-3 through GM-7, a ground water extrac-
tion system consisting of six to ten wells would be constructed.
Pric)r to the installation of the ground water remediation system,
additional investigation of the hydrogeologic regime in the
vicinity of the MEW Site will be performed. The purpose of this
inv~~stigation will be to identify information necessary for the
design of the ground water remediation system. This system would
be used to remove the contaminated ground water. Figure 9
presents a possible configuration of extraction wells and their
relation to the ground water contaminant plume.
8.2"3
Extraction and Discharge to Surface Waters
Alternative (GM-3)
After extraction, the ground water would be discharged
through an effluent monitoring station to a release point along
the Wilson Road ditch. This alternative would essentially remove
the contaminants from the ground water and place them in the
surface water/sediment and atmosphere. It relies solely on
dilution to mee~ the Water Quality criteria. It would increase
the mobility of the contaminants due to volatilization.
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost (15
years, 10%)
15 years
$165,000
°$12,000
$510,000
Extraction with Discharge to Publicly Owned
Treatment Works (POTW) Alternative (GM-4)
After extraction, the ground water would be discharged to the
municipal water treatment system for treatment. This alternative
would continu~ until cleanup levels are met (estimated to be
30 years). Monitoring of the ground water quality would be
needed periodically to ensure that discharge requirements were
met.
8.2.4
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost (30
years, 10%)
30 years
$100,000
$108,OO~
$1,100,OC.
33
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Missouri Electric Works Site
Record Of Decision
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Figure 9 - Conceptual Layout
Extraction Wells
-..---- --
-------
NOTE: All ground water treatment technologies described in
the following paragraphs are estimated to continue for a
period of approximately 15 years. Extraction of ground
water would control migration of the contaminant plume.
Monitoring to evaluate the effectiveness of the treatment
tech~ology and maintenance of the ground water extraction
system would be required for all treatment technologies.
8.2..5
Air-strippinq Alternative (GX-S)
After extraction, the ground water would be pumped through a
fil1:er system to remove suspended particulates. This would be
followed by injection into the top of a packed air-stripper
column equipped with an air blower. The treated water effluent
would then be piped to an outfall along Wilson Road or to the
local Publicly Owned Treatment Works (POTW). The VOCs "stripped"
from the ground water would be processed through a vapor-phase
carbon adsorption filter to prevent the release of VOCs to the
atmc)sphere. A schematic of an air-stripping process is presented
in Figure 10. The volume and quality of the treated effluent
would be monitored prior to its release. Treatability studies
would be needed prior to final design of the system. Process
residuals, such as the spent activated carbon, would require
disposal.
Estimated Time to Implement
Estimated capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost (15
years, 10%)
15 years
$242,000
$64,010
$730,000
8.2.6
Liquid Phase Car~on Adsorption Alternative (GX-6)
After extraction, the ground water would be pumped through a
filter system to remove suspended particulates that could cause
clogging of the carbon bed. Effluent from the filtration unit
would flow to carbon adsorption units. Treated effluent would be
discharged, after sampling and monitoring, to an outfall along
Wilson Road or released to the local POTW. The carbon adsorption
unit.s would require recharging after their adsorption capacities
had been depleted.
.
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost (15
years, 10%)
15 years
$218,875
$85,000
$860,500
35
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-------
8.2.7
Ultraviolet Catalyzed Oxidation Alternative (GH~7)
After extraction, the ground water would be pumped into the
ozone/ultraviolet (UV) unit where hydrogen peroxide would be
addled and mixed, followed by addition of ozone. The mixture would
be :subjected to ultraviolet radiation which acts as a catalyst
for the oxidation reaction. The oxidation reaction "strips"
volatiles from the ground water. off-gases would be decomposed
catalytically. This is an innovative technology. A treatability
study would be required. This alternative destroys the contami-
nants rather than "fixing" them on carbon.
Estimated Time to Implement
Estimated Capital Cost
Estimated Annual Operation and
Maintenance Cost
Estimated Present Worth Cost (15
years, 10%)
15 years
$380,000
$12,000
$850,000
9.0
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The NCP has established nine criteria to be used to evaluate
reme~dial alternatives. To select a remedy, each alternative must
be e.valuated with regard to these criteria and then compared to
each other (see Tables 10 and 11).
The selected remedy is that alternative that provided the
best balance of trade-offs in this comparative analysis.
EPA has determined that the best alternatives for the MEW
Site are SM-ll (onsite incineration) and GM-5 (air-stripping).
As discussed below, SM-ll and GM-5 provide the best balance of
trade-offs among the alternatives with respect to the nine
criteria.
The NCP prioritizes the nine criteria into three categories.
The first such category is threshold criteria. An alternative
must meet the following two requirements to be considered as a
final remedy for the Site:
9.1 Overall Protection of Human Health and the Environment
The selected remedy for soil contamination is to
excavate and thermally destroy the. PCB-contaminated soils. The
selected remedy for ground water contamination is to extract the
contaminated water and treat it by air-stripping followed by
vapor phase carbon adsorption. These alternatives will reduce
the 4axposure to contaminated soils and ground water to protective
levels and also minimize the potential for contaminant migration.
37
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TABLE 10
EVALUATION OF REMEDIAL ALTERNATIVES
IDENTIFIED IN THE FEASIBILITY STUDY
MISSOURI ELECTRIC WORKS SITE
CAPE GIRARDEAU, MISSOURI
PCB contaminated soil
I I I I I I I I I I
, I I I I I I I , ,
Remedial I Protective I Conplies I long-Term , Reduction of I Short- I Can I t , , I I
Alternative , of HLlMn , with IEffect iveness I I , I Term I be I Cost I State 'COIIIIU'I I ty I
!.>J Description ' Health & I ARARs , IMobility' Toxlcityl Volume IEffectlvenessllmplemented' I Acceptance I Acceptancel
co
! Environnent! ! I I I I I I I I I
I I I I I I I I I I I I
I I I I I , I
I I I I I I I I
I SM-1 No Action I No No No No I No No I No Yes I 0 , No I No I
I I I I I ' I I
I SM-2 Limited Action I No No No No ' No No I No Yes I 140,325 I No I No I
I I I I I I , I
ISM-I, Asphal t Cap I No No No No I No No I Yes Yes I 630,000 I No I No I
I I I I I I I I
f SM-6 Offsite landfill ' Yes Yes Yes No ' No No I Yes Yes I 10,900,000 I I I
I I ' I I ' I I
I SM-7 Stabillzatlonl I Yes Yes Yes Yes I No No I Yes Yes I 4,400,000' I- -- I
' Fixation I I I I I I I
I I I I I I I I
I SM-8 Solvent Extraction I Yes Yes Yes Yes I Yes Yes I Yes Yes I 6,400,000 I I I
I ' I I I I I I
I SM-10 In-situ Vitrification I Yes Yes Yes Yes I Yes Yes I Yes Yes I 11,100,000 I I I
I I I I I I I I
I SM-11 On~ite Incineration I Yes Yes Yes Yes I Yes Yes I Yes Yes I 8,400,000 I Yes I Yes I
I
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TABLE 11
EVALUATION OF REMEDIAL ALTERNATIVES
IDENTIFIED IN THE FEASIBILITY STUDY
MISSOURI ELECTRIC WORKS SITE
CAPE GIRARDEAU, MISSOURI
VOC-contaminated Ground Water
I I I I I I I I I I
, , I I ' I I , I I
Remedial I Protective I C~lies' long-Term , Reduction of ' Short- I Can It , I I I
Alternative I of Hunan I with 'Effectiveness I I , ' Term I be , Cost I State I COIIIT'LIni ty I
Description , Health & , ARARs , 'Mobilityl Toxicity' Volume IEffectiveness!lmplemented' I Acceptance I Acceptance I
W , Envl ronnent' , " , I , , I I I
\0 I . I
I I I I I I I I
I I " I I I I
I GM-1 No Action I No No No No ' No No ' No Yes I 0 , No I No I
I I I I " I ,
I GM-2 limited Action I Yes No No No I No No I No Yes ' 37'S,000' No I I
' I I I I I I I
, GM-3 Extraction/Surface ! Yes No No No I No No I Yes I 510,000 I I I
I Water I I I I I I I
I I ' I ' I I I
I GM-4 Extraction/local POTW I Yes Yes Yes Yes ' Yes Yes ' Yes ' 1,100,000' I I
I I " I I I I
I GM-5 Air-stripping I Yes Yes Yes Yes I Yes Yes I Yes Yes I 730,000 I Yes I Yes I
' I I " I I I
I (;M-6 liquid Phase Carbon I Yes Yes Yes Yes I Yes Yes I Yes Yes I 860,000 I I I
I Adsorption , I I I I I I
" I I I ! I I
I (;M-] Ultraviolet Catalyzed I Yes Yes Yes Yes I Yes Yes I Yes Yes I 850,000 I I I
I Oxidation I I I I I I I
I I I J
-------
The No Action (SM-l/GM-l) and soil Limited Action (SM-2)
Alternatives and the Asphalt Cap Alternative (SM-4) do not pro-
vide overall protection to human health and the environment.
These alternatives rely on physical barriers and institutional
controls to reduce or minimize the threat of contact with the
contaminated materials. They do not significantly reduce the
risks to human health or the environment represented by site
conditions, and.therefore unacceptable residual risk remains.
The soil alternatives (SM-I, SM-2, and SM-4) do not provide
any technology which would treat the PCB contamination to
decrease its toxicity, mobility or volume. The PCB contamination
would not be reduced with direct contact limited only by an
asphalt cap or perimeter fencing. The fence would not provide a
barrier to migration of the contaminated soils by either wind or
runoff. Cracking and deterioration of the cap would expose the
underlying contaminated soils. Construction of a cap would
require greater use of institutional controls and the potential
for exposure would still exist. The source of VOC contamination
to the ground water would not be removed by capping the site.
The No Action ground water alternative in unacceptable
because of the uncertainty of possible exposures. Available
information on regional geologic conditions indicates that there
is not a barrier in the limestone bedrock to prevent downward
migration of the contamination for a depth of approximately 1,000
feet. Should no ground water barrier be present, the exposure
and potential exposure to contaminated ground water has not been
adequately addressed.
The ground water Limited Action Alternative (GM-2) may be
considered to be protective of human health and the environment.
While it relies on institutional controls and physical barriers
to minimize the threat of contact with the contaminated
materials, it also incorporates frequent monitoring of the ground
water conditions. The monitoring data would be used to indicate
if the contamination is posing additional risk to human health or
the environment.
Soil Alternatives SM-S, SM-IO and SM-ll, all use techno-
logies that would destroy the PCBs bound to the soils and sedi-
ments. Institutional controls, such as deed restrictions, would
be required for the residually contaminated property because the
residual concentrations would result in unacceptable risk levels
for residential use. However, with institutional controls there
would be no long-term risk above acceptable levels. These tech-
nologies would result in the permanent elimination of the risks
posed by the PCB contamination.
Ground water Alternatives GM-5, GM-6 and GM-7 would provide
permanent elimination of the risks posed by the ground water
contamination by removal and destruction of the volatile organic
40
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compounds.
levels.
The long-term residual risk would be below acceptable
soil Alternative SM-7 would provide long-term reduction of
risks presented by direct contact with PCBs. However, the 99+
p~~rcent destruction of PCBs in the soil and sediment is consid-
ered to be more protective of human health and the environment
than simply encapsulating the contamination in a stabilized soil
monolith.
Neither soil Alternative SM-4 nor ground water Alternative
GH-3 would permanently eliminate residual risk.
9.2
compliance with ARARS
The selected remedies will comply with all federal and state
applicable or relevant and appropriate requirements (ARARs).
Applicable requirements are those state or federal requirements
legally applicable to the release or remedial action contemplated
that specifically address a hazardous substance, pollutant,
cC1ntaminant, remedial action, location or other circumstance
found at the site. If it is determined that a requirement is not
applicable, it may still be relevant and appropriate to the
circumstances of the release. Requirements are relevant and
appropriate if they address problems or situations sufficiently
similar to the circumstances of the release or remedial action
contemplated and are well-suited to the site.
Chemical-specific ARARs associated with the Site include the
Toxic Substances Control Act: the National Ambient Air Quality
Standards: and the National Emission standards for Hazardous Air
Pollutants. Also identified as ARARs for the Site are the
Missouri State Water Quality Standards. As an EPA policy, the
TSCA PCB Spill Cleanup Policy, 40 CFR Part 761, is to be
considered in evaluating alternatives. .
No federal location-specific ARARs were identified for the
Site. However, the presence of a wetland south of the Site must
be considered as the selected remedy cannot adversely affect the
wetland area. A state location-specific ARAR, Protection of
Lakes and streams, Missouri Water Quality standards (10 C.S.R.
20-7.031), was identified for the site.
The federal action-specific.ARARs for the site are: all
pertinent Occupational Safety and Health Act requirements: the
Cl,ean Water Act Regulations applicable to discharges to POTWS:
all pertinent requirements in the Toxic Substances and Control
Act, including its land disposal and incinerator standards for
PCBs: and the Clean Air Act requirements applicable to
incinerators. TSCA .requires that thermal treatment destroy PCBs
at an efficiency of 99.9999 percent with less than 2 ppm resid~,.
toncehtration of PCBs in the ash. A trial burn will be conduct.. :
to demonstrate that this requirement can be satisfied.
41
-------
The No Action and Limited Action alternatives for soil and
ground water do not satisfy chemical-specific ARARs. Nor does
alternative GM-3 (extraction of ground water with discharge to
surface water).
Offsite landfilling of the excavated soils, onsite stabili-
zation/fixation, solvent extraction, and in-situ vitrification
(soil Alternatives SM-6, SM-7, SM-8, and SM-10) and ground water
Alternatives GM-4, GM-6 and GM-7 (extraction with discharge to
POTW, liquid phase carbon adsorption, and ultraviolet catalyzed
oxidation) would meet the chemical-specific, action-specific and
location-specific ARARs identified in Appendix A.
six alternatives, three soil and three ground water, did not
meet threshold criteria. Specifically, these alternatives are:
No Action for both soils and ground water (SM-l and GM-l);
Limited Action for both soils and ground water (SM-2 and GM-2) ;
Asphalt Cap for soils (SM-4); and ground water extraction with
discharge to surface water (GM-3). Because these alternatives
did not meet threshold criteria, they were not considered further
in the comparative analysis of alternatives.
The second category of criteria is Drimary balancing
criteria. The following five criteria are used to evaluate the
alternatives to determine the option that provides the best
balance of trade-offs for the Site.
9.3
Long-Term Effectiveness and Permanence
The selected remedies will eliminate long-term risks associ-
ated with direct contact and potential migration of contaminants
by destroying the PCB contamination through incineration of the
soils onsite and by permanently removing and destroying the VOC
contamination in the ground water by air-stripping followed
through carbon adsorption.
Solvent extraction and in-situ vitrification of the soil
(soil Alternatives SM-8 and SM-10), both involve treatment to
destroy or remove the PCB-molecules. These alternatives would
also eliminate the risks associated with the PCB-contamination.
Soil Alternative SM-7 (stabilization/fixation) would
immobilize the PCB-contaminated soils by stabilizing them.
However, the PCBs would not be destroyed. Accordingly, long-term
monitoring, maintenance and institutional controls would be
required. Degradation of the soil cover over the stabilized
soils could expose the monolith to precipitation runoff (erosive
forces), and freeze/thaw and wet/dry cycles. These forces have
been shown to adversely affect the integrity of stabilized soils.
Moreover, the Site is located in a seismic area. As a result the
integrity of the monolith could be adversely affected by an
earthquake.
42
-------
Offsite landfilling of the contaminated soils (soil
Alternative SM-6) , would remove the contaminated soils from the
Site. However, long-term effectiveness of this alternative is
questionable since landfilling does not destroy or treat the
contaminants.
Ground water alternatives GM-4 (extraction with discharge to
POTW) , GM-6 (extraction with liquid phase carbon adsorption) and
GM-7 (extraction with ultraviolet catalyzed oxidation) would
remove and treat the contaminants. However, long-term effec-
tiveness at the place of disposal for GM-4 is questionable
because the treatment of the ground water contamination would not
be directly controlled by EPA. Alternatives GM-6 and GM-7 would
provide long-term protection.
9.4
Reduction of Toxicity, MObility, or Volume
The selected remedies will achieve reduction of toxicity,
mt:>bility, and volume of contaminants at the Site.
Soil Alternatives SM-8 and SM-lO (solvent extraction and
in-situ vitrification) would treat the contaminated soils to
ac:hieve a reduction in toxicity, mobility and volume. Solvent
extraction would remove the PCBs from the soils and consolidate
them in a liquid form. The liquid would be incinerated offsite,
thereby destroying the PCBs. In-situ vitrification would destroy
the majority vf the PCB contamination by subjecting it to high
tE:amperatures. However, the technology has not been approved by
TSCA as a technology equivalent to incineration or landfilling in
a permitted chemical waste landfill. The residual contamination
would be encapsulated in a vitrified mass, similar to volcanic
glass. A volume reduction of 20 to 40 percent is expe~ted with
in-situ vitrification.
As stated above, soil Alternative SM-7 (stabilization/
fixation) would result in a reduction in the mobility of the
PCBs. However, there would be no reduction in the toxicity of
the PCBs. Moreover, it would result in an increase in the volume
ot: PCB-contaminated materials.
Soil Alternative SM-6
reduction in the mobility,
the contamination from the
landfill.
(offsite landfilling) provides no
toxicity or volume. It merely moves
Site to a permitted chemical waste
Ground water Alternatives GM-4, GM-6, and GM-7 would treat
the contaminated ground water to achieve a reduction in toxicity,
mobility and volume. Liquid phase carbon adsorption (GM-6) woulJ
reduce the toxicity, mobility and volume of the contaminants by
ca.pturing the VOCs on an activated carbon filter and then
"recharging" the spent filter with thermal treatment which will
destroy the VOCs. Ultraviolet catalyzed oxidation (GM-7) woulJ
43
-------
reduce the toxicity, mobility and volume of the VOCs by sub-
jecting them to a chemical reaction process which will destroy
the VOCs present in the ground water.
9.5
Short-Term Effectiveness
The short-term risks associated with the selected remedies
would include the normal construction hazards associated with
excavation of contaminated soils and construction of wells and
installation of a filtration system. Workers onsite could be
exposed to contaminated soils and ground water; these exposures
can be reduced and controlled by use of appropriate health and
safety procedures.
There are risks associated with incinerator operation. .
Improper operation of the incinerator represents the principal
risk. However, these risks are controlled by frequent testing of
the gaseous incinerator emissions and monitoring of the opera-
tions. Employees involved with the incinerator operation will be
required to wear protective clothing as safeguards. As a result,
risks to the public and the environment can be
effectively minimized.
The preferred soil alternative would require approximately
one to two years to complete. The time estimate for installation
of wells and filtration system is two months. The time required
to achieve a reduction in contaminant levels to health-based
levels in the ground water is uncertain, but is expected to take
approximately 15 years. However, extraction of the ground water
should preclude migration of the contaminant plume.
All other alternatives would also have minimal short-term
risks as described above. However, as previously noted, compli-
ance with the action-specific ARARs would effectively minimize
and control the exposures.
The remaining soil alternatives would take about two months
for excavation and stockpiling of the soils. Soil Alternative
SM-6 would be essentially complete at the end of the two-month
time period. It is estimated that soil Alternatives SM-7, SM-S,
and SM-10 would require approximately one year to implement. All
ground water alternatives would take similar amounts of time
(estimate: 15 years) to implement.
9.6
Implementability
Implementation of the selected remedies would involve
use of conventional construction techniques and proven technolo-
gies for the wastes being treated. The reliability and adequacy
of controls on mobile incineration units have been established
through pilot and full-scale tests at several sites. Mobile
incineration units are currently available from several vendors.
Air-stripping of the water followed by carbon adsorption of the
44
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vapor phase is a process used frequently to treat contaminated
ground water.
Soil Alternative SM-7 would require treatability studies to
identify and determine the optimum mixtures of the stabilization
and/or fixation agents to be used. These treatability studies
would probably be performed in two or more phases. The first
phase would be to identify the most effective stabilization and
fixation agents. The second and any following phases would be
nceeded to identify the optimum mixtures or ratios of the
stabilization/fixation additives.
Soil Alternative SM-8 would require a treatability study to
evaluate the effectiveness and implementability of the process for
site-specific soils. The equipment for this process is available
fJrom a limited number of contractors. If equipment is unavailable
at the time of remedial action, then delays would result.
Bench and pilot scale tests for similar cases indicate that
the technology used in Soil Alternative SM-IO (in-situ vitrifica-
tion) would likely be effective for the MEW Site. Power needs
for this alternative are readily available. However, only one
vendor is licensed to use the technology and it currently has
only one unit. This could cause delays at the time of remedial
ac:tion.
Analytical testing of the ground water would be required for
ground water Alternative GM-4. The testing would be needed prior
tC) the local POTW agreeing to accept the ground water for
treatment and processing.
Ground water Alternative GM-6 (liquid phase carbon. adsorp-
tion) is a proven technology. The equipment and materials needed
to effect this remedial alternative are readily available. It
should be implemented relatively easily.
Ground water Alternative GM-7 (ultraviolet catalyzed
oxidation) would require treatability studies to identify any
site-specific operational problems prior to implementation.
Ha.ndling of the hydrogen peroxide could represent some potential
problems; however, use of standard industrial procedures should
minimize any problems and are considered safe. The equipment
used for this technology is fragile and may need to be replaced
du.ring implementation.
9.7
Cost
The costs of the selected remedies would include the
costs associated with onsite thermal treatment, $8..4 million, and
the costs for air-stripping followed by carbon treatment of the
ground water, $730,000. These costs reflect the estimated present
worth of pumping and treating ground water for 15 years.
45
-------
The range of present worth costs for the soil alternatives
is $4.4 million for soil Alternative SM-7 to $11.1 million for
soil Alternative SM-10. The estimated present worth for the
remaining ground water alternatives is $850,000 for Alternative
GM-7 and $1.1 million for Alternative GM-4. Both selected
remedies achieve permanent reduction in the toxicity, mObility
and volume of contaminants at costs that are proportional to
their overall effectiveness.
The following summary is provided of the evaluation of the
soil and ground water alternatives with-respect to the five
primary balancing criteria:
Soils/Sediments
Alternatives SM-8, SM-10 and SM-11 (solvent extraction,
in-situ vitrification, and onsite incineration) would perform
equally with respect to long-term effectiveness; Alternatives
SM-7 and SM-6 (stabilization/fixation and offsite landfill) would
provide less permanent lo~g-term effectiveness. Alternatives
SM-7, SM-8, SM-10, and SM-11 would all reduce the mobility of the
PCB contaminants; SM-6 would not reduce contaminant mobility.
Toxicity and volume of the PCB contaminants would be reduced by
alternatives SM-8, SM-10 and SM-11; no toxicity reduction would
be achieved by SM-6 or SM-7. Alternative SM-6 affords no volume
reduction of the PCB contaminants, while SM-7 would result in an
increase in the volume of PCB-contaminated material. All soil
alternatives considered in conjunction with the primary balancing
criteria would provide short-term effectiveness. Alternative
SM-10 has not been used for a full-scale site cleanup; problems
with this technology could arise which would decrease its ability
to be implemented. Alternative SM-8 may not be effective given
the cohesive nature of the site soils. Residual solvent concen-
trations could remain in the soils making it less attractive.
Alternative SM-7 is the least expensive soil alternative with a
cost of $4.4 million. Soil Alternative SM-10 is the most expen-
sive with a cost of $11.1 million. Onsite incineration costs
fall in the middle of the costs for the alternatives considered.
This remedy provides the best balance of trade-offs among the
alternatives, particularly with respect to long-term effec-
tiveness and the permanent reduction of toxicity, mobility and
volume. .
Ground Water
Ground water Alternatives GM-5, GM-6, and GM-7 were consid-
ered to perform equally with respect to long-term effectiveness:
Alternative GM-4 was considered to be potentially less effective
over the long-term since less control over the process would be
exer~ised by EPA or the MEWSC. All ground water alternatives
considered were judged to provide equal reduction of mobility,
toxicity and volume of the VOC contamination. The short-term
effectiveness of all ground water alternatives was considered t
be equal. All ground water alternatives can be implemented.
46
-------
GW-5 (air-stripping followed by vapor phase carbon adsorption)
was the least expensive alternative, with an estimated cost
$730,000. Alternative GM-4 was the most expensive with an esti-
mated cost of $1.1 million. Remedy GM-5 provides the best
balance of trade-offs among the ground water alternatives, par-
ticularly with respect to long-term effectiveness and permanent
reduction in toxicity, mObility and volume.
The third category of criteria is modifvina criteria. The
following two criteria are considered when evaluating the alter-
natives and are used to help determine the final remedies for the
Site.
9.8
state Acceptance
The State of Missouri has been informed of EPA's selected
remedies: onsite incineration of the PCB-contaminated soils and
air-stripping followed by vapor phase carbon adsorption of the
VOC-contaminated ground water. The State of Missouri has offi-
cially notified EPA of its concurrence with the selected remedial
actions.
9.9
Community Acceptance
The community and other interested citizens or parties were
given the opportunity to review the Proposed Plan and supporting
documents of the Administrative Record. A thirty-day comment
period was available for the public to comment on these docu-
ments. A Public Hearing was held in Cape Girardeau on August 30,
1990 to discuss the Proposed Plan and the preferred remedial
alternatives. No comments on the Proposed Plan were received at
that Public Hearing. There have been no comments indicating
st.rong opposition from the general public to the preferred
alternatives identified in the Proposed Plan. Comments that were
su.bmitted are addressed in the Responsiveness Summary.
10.0
THE SELECTED REMEDY
soils/Sediments
10.1
The remedial action selected for the soil cleanup will
provide overall protection of human health and the environment by
eliminating, reducing and controlling all current and potential
ri.sks posed by the exposure path~ays at the Site, and will be in
compliance with all applicable or relevant and appropriate
re:quirements (ARARs). The long-term effectiveness and permanence
of the selected soil remedy were determined to be critical
factors in balancing the trade-offs among the other soil
alternatives.
The statutory preference of CERCLA ~121(b) to permanently
and significantly reduce the volume, toxicity, or mobility of the
ha~ardous substances through treatment technologies (to the
maximum extent practicable) is satisfied by the selected soil
47
-------
remedy. The technology selected is a proven technology. Case
studies of other cleanups indicate that onsite incineration is a
consistent practical approach to permanent destruction of PCBs.
This remedy should be relatively easy to implement from both a
technical and administrative point of view. Mobile incineration
units are available from several vendors and therefore should be
readily available.
The cost of implementing the selected soil remedy, onsite
incineration, was considered during EPA's evaluation process.
The results of this comparative analysis indicated that while the
costs associated with onsite incineration do exceed the cost
associated with the other source control alternatives analyzed
(stabilization/fixation and solvent extraction), these costs are
proportional to the overall greater effectiveness of onsite
incineration.
Rotary kiln incinerators are probably the most common type
of equipment used for mobile incineration because they have been
commercially proven, provide flexibility in handling many types
of materials and provide good mixing and long residence times for
solids. Rotary kilns are equally applicable to solids, sludges,
and slurries and are capable of receiving and processing liquids
and solids simultaneously. The five basic components of the
rotary kiln system are: 1) rotary kiln (primary combustion
chamber): 2) secondary combustion chamber: 3) heat recovery
boiler: 4) air pOllution control train: and 5) effluent neutrali-
zation chamber. The soil is fed into the rotary kiln that is
mounted on an incline. Temperatures range from 1,200 to 1,800
degrees Fahrenheit and the residence time depends on the contami-
nants being treated. Typical feed rates for soils are 1,300 to
1,400 pounds per hour. The soil is removed at the lower end of
the kiln and the vapors desorbed from the soil then enter the
secondary chamber, at temperatures of 1,500 to 3,000 degrees
Fahrenheit, to complete oxidation. As the exhaust gases exit the
.secondary chamber, they are directed through a pollution control
train which may consist of a water quench, a packed scrubbing
tower or an ejection scrubber system.
Implementation of onsite incineration at the MEW site would
consist of the following tasks. preparation of the site will be
performed by clearing trees and vegetation in the area where the
incinerator is to be placed. contaminated soils will be
excavated and consolidated onsi~e with provisions to minimize
migration of the contaminated materials. The incinerator will be
brought to the Site, at which time trial burn(s) will be
performed, tested and evaluated before the incineration of the
PCB-contaminated soils will be done. When the incineration is
complete, the incinerator will be removed from the Site. The
Site will be restored and revegetated. Figure 11 is a flow-
diagram of the PCB-contaminated soil remedial action.
48
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OBSITE IBCIBBRATION
~SSOURI ELECTRIC WORIB SITE
I SITE PREPARATION
SOIL EXCAVATION/
CONSOLIDATION
MOBILIZATION OF
INCINERATOR
I
I TRIAL I
BURN
t TESTING I
I
REVIEW ,
EVAWATION
MODIFICATIONS AS
NECESSARY
INCINERATION OF PCB-
CONTAMINATED SOILS
TESTING/
ANALYSES
EVALUATION
DEMOBILIZATION OF
INCINERATOR
INCINERATOR
ASH USED
TO BACKFILL
EXCAVATED
AREAS
REMOVAL/DISPOSAL
OF CONCRETE PAD
Missouri Electric Works Site
Record Of Decision
I 81'1'2
RESTORATION
Figure 11 - Flow Diagram of
PCB-Contaminated Soils-
Remedial Action
49
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site preparation activities would consist of clearing an
area approximately one acre in size where the incinerator would
be setup. Contaminated soils from this area would be stockpiled
in the immediate vicinity to await processing when the
incinerator is in-place and operational. A concrete pad would be
constructed in the cleared area to support the processing
equipment. other Site preparation activities would include
removal of trees and miscellaneous trash and debris present on
the Site in those areas with PCB levels greater than 10 ppm.
Excavation and consolidation of all on and offsite contami-
nated soils with PCB concentrations greater than 10 ppm would
have to be performed. Excavation of the soils and any other
contaminated materials would be accomplished using conventional
heavy construction equipment. Excavated materials would be
staged for processing near the incinerator in stockpiles. These
stockpiles would be established, with appropriate runoff and wind
dispersion protective devices, for both contaminated feed
materials (contaminated soils) and the process residuals. The
residuals would be used to backfill the onsite excavated areas.
Clean soils would probably be required to complete Site
restoration and final grading.
Permitting for the onsite incinerator will not be required,
as this remedial action will be performed onsite. However, a
trial burn will be required, as will frequent monitoring and
analytical tests, to establish that the incinerator complies with
all substantive requirements applicable to a TSCA incinerator.
After constructing the concrete pad in the processing area,
the incinerator will be mobilized to the Site. The incinerator
will be brought to the Site using highway or railroad
conveyances. Upon arrival at the site, the incinerator will be
setup in its working configuration.
A trial burn will be performed after incineration set-up is
complete. The primary reason for a trial burn is to provide
data, both operational and analytical, that verifies that the
incinerator complies with all substantive requirements of a
permitted TSCA incinerator. In addition, the data generated will
be used to identify the residence time needed to meet PCB
destruction requirements and to monitor the emissions from the
incinerator.
.
After the data generated by the trial burn has been reviewed
and evaluated by State and Federal authorities, approval to begin
"production-type" operations will be given, if all substantive
requirements of a permitted unit have been met. Operations will
consist of sizing of the stock-piled contaminated materials in
preparation for incineration. These sized materials will be fed
into the incinerator using equipment similar to a pug-mill. Feed
rates will be monitored continuously. Emissions from the incin-
. erator, both ash and gases, will be monitored frequently (not
less than daily) to document that destruction efficiencies and
50
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air emissions standards are complied with. In addition, the ash -
residuals will be tested to identify its leaching characteristics
and to identify the compounds within the ash. The leaching
characteristics will be identified using the Toxicity
Characteristic Leaching Procedure (TCLP).
After the PCB-contaminated soils and other materials have
been destroyed by incineration, the incinerator and other appur-
tenant equipment will be demobilized and removed from the site.
The concrete pad will be tested to ascertain whether it was
contaminated during incineration operations. If it is not con-
1:aminated, the concrete pad will be removed and disposed of in a
sanitary landfill. If the concrete pad is found to be contami-
nated, disposal in a licensed chemical waste landfill will be
necessary.
As the residual ash from incineration operations is produced
and tested, it will be used to backfill the excavated areas on
the Missouri Electric Works, Inc., property. The residual ash
will be spread and compacted using conventional heavy construc-
tion equipment. Soil, that has been verified as being uncontami-
nated with analytical tests, will be used to backfill other
portions of the Site. The entire Site will be restored to its
original grade using this verified "clean" material. The soil
will be spread and compacted using conventional means.
The final grading of the site will be such that the natural,
drainage of the site is controlled or managed. This will be done
to ensure that erosional features, similar to those presently
existent at the Site, do not reform.
A 6- to 12-inch layer of topsoil will be spread over the
entire Site. This topsoil will be seeded or sod will be placed
to revegetate the Site.
Institutional controls, such as deed restrictions and/or
zoning restrictions will be imposed to limit use of the Site to
industrial or commercial purposes.
10.2
Ground Water
The selected ground water remedy will provide overall
protection of human.health and the environment by reducing and
controlling all potential risks.posed by ingestion of the ground
water. The selected remedy will comply with all applicable or
re!levant and appropriate requirements (ARARs). The selected
remedy will use a proven technology that is readily available
from several vendors at a costs that is proportional to its
overall effectiveness.
This remedial technology involves collection of ground wat~:
utilizing an extraction well network, temporary storage, folIo..,:
by removal of volatile organics utilizing an air-stripper with
gas phase carbon adsorption from the air stream. Polishing of
51
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the liquid stream utilizing liquid phase carbon adsorption can
also be included, as necessary. Volatile contaminants are trans-
ferred from the ground water to the air, via continuous contact
in the tower. The ground water stream is introduced at the top
of the tower while air is blown into the base of the tower and
flows upward, contacting with the water.
Air-stripping is an efficient means of removing volatiles
for compounds with Henry's Law Constants greater than 0.001
(applies to all the VOCs at the MEW Site). The air-stripper
off-gas is treated by vapor phase carbon adsorption to prevent
release of the stripped contaminants to the atmosphere.
Prior to the installation of the ground water remediation
system, additional investigation of the hydrogeologic regime in
the vicinity of the MEW Site will be performed. The purpose of
this investigation will be to identify the vertical extent of
contamination; confirm the presence or absence of a continuous
aquiclude within the upper 200-300 feet of the bedrock; perform
pump tests to determine the flow rates and hydraulic conductivity
of the aquifer; confirm the flow direction of the aquifer; and
identify other data that will be necessary for the design of the
ground water remediation system.
Elements required for implementation of the ground water
remedy include the following:
The aquifer will be tested, either by pump or' slug tests, to
identify flow rates and hydraulic conductivity of the
aquifer. This information will be needed to design the
extraction well network to optimize its removal efficiency.
In addition, the water extracted during the pump tests will
be sampled and analyzed to better identify the contaminants
and associated concentrations present in the ground water.
Design parameters affected by the results of this testing
include: the size of the wells, pumps and storage tanks; the
length of pumping time; the size of the air stripping tower;
and the amount of activated carbon needed to filter the vapor
phase.
Ground water from the Site will be used in a bench-scale air-
stripper test to evaluate the effectiveness of the system on
the site contam~nants. The information gathered from these
tests will be used to adjust design parameters to achieve
optimum contaminant reduction and removal.
After the data from these tests are available, a conceptual
design of the extraction well network will be produced. This
conceptual design will be studied and reviewed to identify if
a more efficient or cost-effective option exists. When this
peer review is complete, the extraction well system will be
designed. This design will include well locations, pump
sizes, pumping frequency, location and sizes of connecting
52
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piping, the size and location of the storage tank and the
location of the air-stripper.
The data gathered during the aquifer tests and the treat-
ability study will be used to develop the specifications for
the air-stripper to be used at the Site. These specifica-
tions will be used to identify the venaor with the most
appropriate unit for the Site. An air-stripper, modified as
necessary to meet Site criterion, will then be purchased.
The purchased air-stripper system will be assembled onsite.
The air-stripper will have piping for discharge of the proc-
essed water to the local POTW or to the wetland area via a
surface water discharge.
The extraction wells will be strategically located to inter-
cept the contaminated ground water. The storage tank will be
installed with piping connected to the air-stripper.
After the extraction wells and appurtenant piping and utili-
ties and the air-stripper system are installed the entire
system will be connected. Pressure testing or visual inspec-
tion of all connections will be performed as appropriate.
The system then will be started-up and cleanup of the ground
water initiated.
Discharges from the air-stripper system will be monitored
frequently, both the vapor and liquid phase. The analytical
data from monitoring will be evaluated to ensure that the
discharges are in compliance with the regulations for surface
water and air emissions. Adjustments to the system will be
made to ensure that all appropriate regulations are complied
with. Those portions of the system with a finite operational
life, i.e., activated carbon filters, water filter; water
pumps, etc., will be replaced as necessary to keep the system
operational.
Samples of the ground water will be obtained and analyzed to
evaluate the performance of the air-stripper system. The
extraction and air-stripping of the ground water will con-
tinue until risk criteria or regulatory limits are met.
After regulatory limits are met and maintained for a period
no less than one year, the system will be shut-down. After
shut-down the ground water will be monitored on a quarterly
basis for a period of at least two years. If during this
time, the contaminant concentrations do not increase above
regulatory limits, the air-stripping system will be decommis-
sioned and the extraction wells abandoned in compliance with
the requirements set forth by the State of Missouri.
Pursuant to CERCLA ~l21, any remedial action that results :~
any hazardous substances, pollutants, or contaminants remaining
at the Site shall be reviewed no less often than five years aft.,:
the initiation of such remedial action to ensure that human
5J
-------
health and the environment are being protected by the remedial
action being implemented.
Because the remedial actions for the site will result in
hazardous substances remaining in the onsite ground water and
will require that institutional controls be placed on the Site
the overall Site conditions will be reviewed at least once every
five years after the initiation of the remedial action at the
Site. This review will be consistent with the CERCLA standards
applicable for five-year site reviews in effect at the time of
the review. The extent and nature of this review program will be
developed during the design phase of the selected remedy, but
will include at a minimum, those data collected during the moni-
toring programs identified above for the ground water and the
onsite incinerator.
11.0
STATUTORY DETERMINATIONS
The remedial actions selected for implementation at the
Missouri Electric Works site are consistent with CERCLA and, to
the extent practicable, the NCP. The selected remedies are
protective of human health and the environment, attain ARARs, and
are cost-effective. The selected remedies also satisfy the
statutory preference for treatment which permanently and signifi-
cantly reduce the toxicity, mobility, or volume of hazardous
substances as a principle element.
The selected remedies for the site will address the release
or threat of release posed by the contaminated soils, sediments
and ground water. The remedies selected are thereby protective.
The soil and sediment cleanup levels to be attained through
excavation and onsite incineration will reduce the risks associ-
ated with these contaminated materials to a level protective of
human health and the environment. These cleanup levels address
the risks from direct contact, inhalation and ingestion of the
contaminated soils or sediments or the vapors originating from
the contaminated soils and sediments.
The extraction and onsite
comply with the cleanup levels
cleanup levels are the Federal
criteria.
treatment of the ground water will
established for the site. These
MCLs and the Missouri ground water
The selected remedies will meet or attain all applicable or
relevant and appropriate Federal and state requirements that
apply to the Site. Federal and State laws which are applicable
or relevant and appropriate are identified in Appendix A.
. .
12.0
DOCUMENTATION OF SIGNIFICANT CHANGES
There were no significant changes made to the Proposed Plar.
in this Record of Decision.
54
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APPENDIX A
SUMMARY OF APPLICABLE OR RELEVANT AND
APPROPRIATE REQUIREMENTS (ARARs)
AND liTO BE CONSIDERED" (TBC) CRITERIA
-------
TABLE. 1
FEDERAL CHEMICAL-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
STANDARD, REQUIREMENTS,
CRITERIA. Q! LIMITATION
CITATION
National Primary Drinking
Water Standards
1,0 CFR Part 11,1
National Secondary Drinking
Water Standards
1,0 CFR Part 11,3
Maximum Cont8lllinant Level
Goals
1,0 CFR Part 11,1
>
I
~
Water Quality Criteria
1,0 CFR Part 131
Quality Criteria
for Water, 1986
Releases frOB Solid Waste
Management Units
1,0 CFR Part 264
Subpart F
National Ambient Air
Qual i ty Standards
1,0 CFR Part 50
National Emission Standards
for Hazardous Air Pollutants
1,0 CFR Part 61
DESCRIPTION
Establishes health-based
standards for public water
systems (maximum contaminant)
levels).
Establishes welfare-based
standards for public water
(secondary maximum contaminant
levels).
Establishes drinking water
quality goals set at levels of
no known or anticipated
adverse health effects with an
adequate margin of safety.
Sets criteria for water quality
based on toxicity to aquatic
organisms and human health.
Establ ishes maximum contaminant
concentrations that can be
released from hazardous waste
units in Part 264, Subpart F.
Establishes primary (health
based) and secondary (wel fare
based) standards for air quality.
Establishes emission levels for
certain hazardous air
pollutants.
APPLICABLE
RELEVANT AND
APPROPRIATE
Yes
Yes
Yes
Yes
Yes
Yes
Yes
page 1 of 2
£!!!!ill
The MCLs for organic and
inorganic contaminants are
relevant and appropriate for
ground water.
Secondary MCLs for these
parameters/contaminants may be
relevant and appropriate for
ground water.
Proposed MClGs for organic
contaminants should be treated as
"other criteria, advisories
and guidance".
AWCs may be relevant and
appropriate for surface water
discharges.
Onsite hazardous waste
IIIBnagement uni t may be
considered. Same levels as MCLs.
Standards for particulate matter
RUst be monitored .ct..lring some
remedial activities.
Standards for some chemicals may
relevant and appropriate to the
Site.
-------
TABLE A-I (continued)
FEDERAL CHEMICAL-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
STANDARD, REQUIREMENTS,
CRITERIA. Q! liMITATION
CITATION
DESCRIPTION
Occupational Health and
Safety Regulations
29 CFR 1910.1000
Subpart Z .
Establishes permissible
exposure limits for work-place
exposure to many chemicals.
Toxic Substances Control Act
CTSCA)
Establishes prohibitions of
of and requirements for the
manufacture, processing,
distribution in commerce, use
disposal, storage and marking
of PCB items. Sets forth PCB
Spill Cleanup Policy.
40 CFR Part 761
>
I
N
AWLI CABLE
RelEVANT AND
APPROPRIATE
Yes
Yes
page 2 of 2
~
listed chemicals detected on-
site. Standards applicable to
remedial worker exposure.
The PCB Spill Cleanup Policy
(Part 761.25) is a TBC which
establishes cleanup guidelines
for nonregulated access areas.
Part 761.60 requirements for the
storage and disposal of PCB-
contlllllinated soi l and provides a
basis for utilizing alternative
technologies for PCB treatment.
Part 761.70 establishes
requirements for PCB incin-
erators, which are applicable if
onsite or offsite incineration
is involved.
Part 761.75 establishes require-
ments for chemical waste land-
fills for land di~posal of PCBs
at concentrations of less than
500 ppn.
-------
STANDARD, REQUIREMENTS,
CRITERIA. Q! liMITATION
CITATION
Missouri S.fe Drinking ~.ter
Act and Missouri Yater
Quality St.ndards
10 CSR
20-7.031
Missouri H.z.rdous ~.ste
Management Regul.tions
10 CSR
25-10.010
TABLE A-2
STATE CHEMICAL-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
DESCRIPTION
Maximum chemical
contaminant levels
and monitoring
requirements
Procedures for
obtaining state approval for
remedial actions at abandoned
or uncontrolled sites.
Procedures and requirements for
managing waste oil, which .re in
addition to Federal requirements
on used oil.
>
I
W
Missouri H.z.rdous Yaste
Management Regulations .
10 CSR 25-11.010
Standards for management of
waste materials or waste
manufactured items containing
PCBs at concentrations of fifty
parts per million or more.
Missouri Haz.rdous Waste
Management Regul.tions
10 CSR 25-13.010
Missouri H.z.rdous ~aste
Management Regulations
10 CSR 25-6.263
Standards for Transporters
of Hazardous Yaste
APPLICABLE
RelEVANT AND
APPROPRIATE
Yes
Yes
Yes
Yes
Yes
9!!!lli
The requirements may
be relevant and
appropriate for the
MEY Si te.
The requirements may
applicable for the MEY Site.
These procedures may be
applicable for the MEY site if
removal of non PCB-contaminated
oil is involved as a remedial
action.
These standards may be applicable
or relevant and appropriate
requirements for the MEY Site.
These requirements may be
applicable for the HEY Site if
removal offsite of hazardous waste
non-PCB contaminated oils or PCB
materials.
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TABLE A-3
FEDERAL LOCATION-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
STANDARD, REQUIREMENTS,
CRITERIA. 2! LIMITATION
APPLICABLE
RELEVANT AND
APPROPRIATE
CITATION
DESCRIPTION
Protection of Wetlands
40 CFR 6.302(a)
and Appendix A
Requires Federal agencies to
avoid, to the extent possible,
the adverse impacts associated
with the destruction or loss of
wetlands and to avoid support
of new constr'JCtion in wetlands
if a practical alternative exists.
Exec. Order
No. 11,990
Yes
»
I
~
~
The U.S. Army Corps of Engineers
has identified a jurisdictional
wetland near the MEW Site.
-------
TABLE A-4
STATE LOCATION-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
STANDARD, REQUIREMENTS,
CRITERIA. Q! LIMITATION
CITATION
Protection of Lakes
and Streams
Missouri Water
Quality Standards
10 CSR 20-7.031
>
I
VI
DESCRIPTION
Promulgates rules to protect
quality of lakes and streams.
Beneficial uses of Cape La Croix
Creek listed as livestock and
wildlife watering and warm water
fishing.
APPLICABLE
RELEVANT AND
APPROPRIATE
Yes
m!!lli
Chemical specific ARARs are
listed in Table A-2.
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TABLE A-5
FEDERAL ACTION-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
APPLICABLE
STANDARD, REQUIREMENTS,
CRITERIA. Q! LIMITATION
DESCRIPTION
RElEVANT AND
APPROPRIATE
CITATION
CLEAN WATER ACT
33 USC 1251-1376
National Pollutant Discharge
Elimination System (NPDES)
40 CFR Part 125
Requires permits for the
discharge of pollutants for any
point source into waters of the
United States.
Yes
National Pretreatment 40 CFR Part 403 Sets standards to control Yes
Standards pollutants which pass through or
> interfere with treatment
I processes in public treatment
C3'
works or which may contaminate
sewage sludge.
SOLID WASTE DISPOSAL ACT ("SWA") 42 USC 6901-6987
Criteria for Classification of 40CFR Part 257 Establishes criteria for use in Yes
Solid Waste Disposal facilities determining which solid waste
and Practices disposal facilities and practices
pose a reasonable probability of
adverse effects on public health
or the environment and thereby
constitute prohibited open dumps.
Standards Appl icable to 40 CFR Part 262 Establishes standards for No
Generators of Hazardous generators of hazardous waste.
Waste
'.. . ..,.. -I, .' ~(I1A ''''ulel'on.. 10 wasles found on the site is will be determined after receipt of TeLP data.
page 1 of 3
£f!!!!lli
Permit not required for CERCLA
activities; however, technical
requirements for discharge must
be met if onsite water treatment
occurs and is discharged to
surface water.
Only if the treated ground water
is discharged to a publicly
owned treatment works.
The soil selected remedy will
involve onsite disposal of
incinerator ash.
The selected remedies do not
involve offsite transportation
of either sailor ground water
for treatment or disposal.
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TABLE A-5 (continued)
FEDERAL ACTION-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
APPLI CABLE
STANDARD, REQUIREMENTS,
CRITERIA. Q! LIMITATION
CITATION
DESCR IPTION
Standards Applicable to
Transporters of Hazardous
Yaste
Establishes standards which apply
to transporters of hazardous waste
with the US if the transportation
requires a manifest under
40 CFR Part 262.
40 CFR Part 263
Contingency Plan and
Emergency Procedures
Subpart 0
II
Manifest System, Record-
II
Subpart E
>
I
'-J
Subpart I
II
Use and Management of
Containers
Tanks
Subpart J
II
Yaste Piles
Subpart L
II
Incinerators
Subpart 0
II
Land Disposal
40 CFR Part 268
Establishes restriction for
burial of wastes and other
hazardous materials.
RELEVANT AND
APPROPRIATE
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
page 2 of 3
~
The selected remedies do not
involve offsite transportation
of hazardous wastes for treatment
and/or disposal.
If onsite ground water treatment
system produces hazardous waste.
If the selected remedies
the offsite transport of
hazardous waste.
involve
If the selected remedies involve
storage of containers.
If the selected remedies
involve the use of tanks to treat
or store hazardous materials.
If the selected remedies would
treat or store hazardous
materials in piles.
The selected remedy for soils is
onsite incineration. Also
covered by CFR 761.70.
If the selected remedies would
offsite burial of contaminated
soils or residues containing
prohibited wastes, a CERClA
waiver may be required.
-------
TABLE A-5 (continued)
FEDERAL ACTION-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
page 3 of 3
APPLI CABLE
STANDARD, REQUIREMENTS, RELEVANT AND
CRITERIA. Q! LIMITATION CITATION DESCRIPTION APPROPR I ATE C(JtMENT
OCCUPATIONAL SAfETY AND 29 USC 651-678 Regulates worker health and Yes Under 40 CfR 300.38, requirements
HEALTH ACT (OSHA) 29 CFR Par 1910 safety at hazardous waste sites. of the Act apply to all response
activities under the NCP.
HAZARDOUS MATERIALS TRANS~TATION ACT 49 USC 1801-1813
Hazardous Materials 49 CfR Parts 171-178 Regulates transportation of Yes If selected remedy would involve
Transportation Regulations hazardous materials. transportation of hazardous
materials.
TOXIC SUBSTANCES CONTROl ACT 13 USC Sec. 2601-2629
» PCB Requirements 40 CfR Part 761 Establishes storage and disposal Yes Treatment and disposal method-
I
ex; requirements for PCBs. ologies must meet substantive
requirements set forth by
40 CfR 761.
PCB Spill Cleanup Policy 40 CFR 761 Establishes cleanup procedures Yes Specifies soil cleanup levels
for PCB spills. and excavation requirements.
-------
TABLE A-6
STATE ACTION-SPECIFIC ARARs
MISSOURI ELECTRIC WORKS SITE
APPLICABLE
STANDARD, REQUIREMENTS,
CRITERIA. Q! LIMITATION
CITATION
DESCRIPTION
Missouri Hazardous Waste
Management Regulations
10 CSR 25-10.010
Procedures for obtaining State
approval for remedial actions at
abandoned or uncontrolled sites.
Missouri Hazardous Waste
Management Regulations
10 CSR 25-11.010
Procedures and requirements for
managing waste oil, which are in
addi t i on to Federal requi rements
on used oi I.
Missouri Hazardous Waste
Management Regulations
10 CSR 25-13.010
Standards for management of waste
materials or waste manufactured
items containing PCBs at
concentrations of fifty parts per
million or more.
>
I
\D
Missouri Hazardous Waste
Management Regulat ions
10 CSR 25-6.263
Standards for Transporters
of Hazardous Waste.
RELEVANT AND
APPROPRIATE
~
Yes The requirements may be appl ic-
able for the MEW Site.
Yes
Yes
Yes
The procedure may be applicable
for the MEW Site if removal of non
PCB-contaminated oil is involved.
These standards may be applicablel
relevant and appropriate
requirements for the MEW Site.
These requirements may be
applicable for the MEW Site if
removal offsite of hazardous
waste, non-PCB contaminated oil
or PCB materials.
-------
RECORD OF DECISION
REMEDIAL ALTERNATIVE SELECTION
THE RESPONSIVENESS SUMMARY
MISSOURI ELECTRIC WORKS SITE
CAPE GIRARDEAU, MISSOURI
prepared By:
U.S. Environmental Protection Aqency
Reqion VII
Kansas City, Kansas
september 1990
-------
1.0
2.0
3.0
3.1
3.2
MISSOURI ELECTRIC WORKS SITE
RECORD OF DECISION
RESPONSIVENESS SUMMARY
TABLE OF CONTENTS
Page
OVERVI EW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
BACKGROUND ON COMMUNITY INVOLVEMENT...................1
SUMMARY OF COMMENTS RECEIVED DURING THE
PUBLI C COtJIMENT PERIOD................................. 2
Comments
from Interested citizens.....................2
Comments from Potentially Responsible Parties.........5
-------
Missouri Blectric Works site
Cape Girardeau, Missouri
Responsiveness Summary
1.0
OVERVIEW
In the Proposed Plan released to the pUblic, the
Environmental Protection Agency (EPA), with Missouri Department
of Natural Resource (MDNR) concurrence, made a preliminary selec-
tion for the preferred alternative for remedial action at the
Missouri Electric Works site. EPA's recommended alternatives
addressed the PCB-contaminated soils and sediments and the con-
taminated ground water at the Site. The preferred alternative
involved excavation and onsite incineration of the PCB-contami-
nated soils and sediments and extraction and treatment, using an
air-stripper, of the contaminated ground water.
Judging from the comments received during the public comment
period, the residents of Cape Girardeau generally accepted the
preferred alternative as presented. With the exception of one
comment, opposition to the preferred alternative for the soils
and sediments was not indicated.
2.0
BACKGROUND ON COMMUNITY INVOLVEMENT
EPA and the Missouri Department of Health held meetings with
adjacent property owners and other interested citizens in Cape
Girardeau, Missouri on July 11 and 12, 1989. The purpose of
these meetings was to discuss the site conditions and the health
risks that the Site represented to the general public. EPA staff
participated in two local Cape Girardeau, Missouri radio talk
shows during July 1989; interested citizens were able to
"call-in" and ask questions of the EPA staff concerning the
Missouri Electric Works site and the related activities.
The Administrative Record was placed in the Cape Girardeau
Public Library on August 11, 198!!). The documents contained in
the administrative record identified the need for a Remedial
Investigation/Feasibility Study (RI/FS). A public meeting was
held in Cape Girardeau on september 19, 1989 to inform the public
of the details of the ongoing remedial investigation and to
identify possibly remedial alternatives that would be considered
during the feasibility study. A second public meeting was held
1
-------
on June 11, 1990 to inform the public of the remediai investiga-
tion findings and to again identify the remedial alternatives
that would be considered during the feasibility study. Fact
sheets, identifying significant Site activities, were issued to
everyone on EPA's mailing list for the Site in June, August, and
November 1989 and March, May and July 1990.
The RI/FS and Proposed Plan for the Missouri Electric Works
site were released to the public during August 1990. These three
documents were made available to the public in the administrative
record and its addendum located in the EPA Record Center, Region
VII and at the Cape Girardeau, Missouri Public Library. The
notice of availability for these three documents was published in
the News Guardian and the Southeast Missourian on August 19,
1990. A public comment period was held from August 19 to
September 17, 1990. In addition, a public hearing was held on
August 30, 1990. At this meeting, representatives from EPA, the
Missouri Department of Natural Resources, the Missouri Department
of Health and the Agency for Toxic Substances and Disease
Registry (ATSDR) were available to answer questions about prob-
lems at the Site and the remedial alternatives under
consideration.
3.0
SUMMARY OF COMMENTS RECEIVED DURING THE
PUBLIC COMMENT PERIOD
Comments raised during the public comment period on the
draft Feasibility study (FS) and Proposed Plan are summarized
below. The Public comment period was held from August 19 to
september 17, 1990.
3.1
Comments from Interested'citizens
Comment '1
Ruth Hathaway, Chairman of the Local Emergency Planning
Committee, and Bruce Hathaway, Associate Professor of Chemistry
at Southeast Missouri State University, wrote to express their
support of EPA's preferred alternative of onsite incineration.
They indicated that this alternative was an efficient and
effective way to dispose of PCBs.
Response
As indicated in the proposed plan, it is EPA's opinion that
onsite incineration is the alternative that meets threshold
criteria and provides the best balance between the "primary
balancing criteria" as identified in the NCP.
2
-------
C:ommen t .2
~[r. C. J. Morrill, who owns the property adjacent to the MEW
property and operates a construction business from that property,
asked several questions concerning specific details of the actual
remedial action.
Response
The proposed plan indicates that it is estimated that the onsite
incineration of PCB-contaminated soils will take about two years:
the ground water extraction and treatment is anticipated to
continue for approximately 15 years. It is not possible, at this
time, to answer the questions regarding the specifics of actual
remedial action items since the design has not been initiated nor
the contractor selected. The answers will remain unknown until
the design for the remedial action has been completed and with
respect to ground water, until the cleanup levels are achieved.
EPA will be overseeing and monitoring the remedial action efforts
while they are performed.
Comment .3
Mr. Morrill also asked some questions regarding onsite
incineration. Specifically, he wanted to have a detailed expla-
nation of what incineration involves: how it would be completed:
how the materials would be handled; how emissions would be
handled: when would the "burning" take place; what would happen
to the residues; what type of backfill material would be used;
would the area be revegetated; and concerns about his employees'
health and safety during remediation.
Response
There are five basic components to a rotary kiln incinerator
(which is the most common type of incinerator and may be chosen
for the remedial action). These components are: 1) the rotary
kiln (primary combustion chamber); 2) secondary combustion
chamber; 3) heat recovery boiler; 4) air pollution control train:
and 5) effluent neutralization chamber. The soil is fed in to
the rotary kiln that is mounted on an incline. Temperatures
range from 1,200 to 1,800 degrees Fahrenheit and the residence
time depends on the contaminants being treated. Typical feed
rates for soils is 1~300 to 1,400 pounds per hour. The soil is
removed at the lower end of the kiln and the vapors removed from
the soil. The vapors are then processed through the secondary
chamber at temperatures of 1500 to. 3000 degrees Fahrenheit, to
conplete oxidation. As the exhaust gases exit the secondary
chamber, they are directed through a pollution control train
which may consist of a water quench, a packed scrubbing tower or
3
-------
an injection scrubber system. Details of what is anticipated for
the onsite incineration system at the MEW Site are presented on
pages 47 through 51 of the Decision Summary and graphically on
Figure 11.
Conceptually, there are no plans to stop the onsite
incineration process once it begins. The soils will be
excavated, processed, incinerated, tested and used as backfill on
the MEW property.
Conceptual plans would be to stockpile excavated contami-
nated soils on the MEW property to await incineration. Only very
short haul distances are anticipated.
As indicated above, emissions from the incinerator would be
processed through a pollution control train to ensure that any
releases to the atmosphere are minimized and are in compliance
with the standards set by the Clean Air Act and the Toxic
Substances Control Act. Frequent monitoring of the emissions
will be performed. Analytical testing of the exhaust gases will
be done frequently.
The actual hours during the day that the incinerator will be
operating cannot be identified at this time. It is a question
that can be better answered after remedial design is completed
and the remedial action is underway.
The soil "ash" which remains after incineration will be
tested using Toxicity Characteristic Leaching Procedure (TCLP)
test methods. (A fact sheet on the final Toxicity Rule is
attached). This testing procedure will identify if the ash is
hazardous. It is anticipated that the ash will not be hazardous,
and, thus, it will be used as a backfill material on the MEW
property. A clean soil cap will be placed over the ash.
Specifics of Site restoration are not available and will not
be available until after the remedial design are complete. It is
anticipated that the excavated areas outside the MEW property
will be backfilled using a verified non-contaminated soil from a
relatively local borrow source. After backfilling operations are
complete, the area will be revegetated.
Compliance with the ARARs will minimize any risk during the
remedial action, as discussed in the Record of Decision. Risks
to Morrill Construction employees, on Morrill property, is not
anticipated to be significantly different during the remedial
action than they are now. Morrill employees should stay away
from the excavation and backfill operations on Morrill property
until they are complete. Morrill employees should also stay away
from the incinerator and associated operations. After the reme-
dial action, the threat to human health and the environment posed
4
-------
by the PCB-contamination will be eliminated.
C:omment '4
Mr. Brian Gardner, legal representative of Hall Street
A.ssociates which owns property adjacent to MEW property,
expressed concerns regarding the specific areas which would be
cleaned during the remedial action. His client was concerned
since EPA had notified it during 1987 that PCBs at concentrations
of 88 ppm had been detected on the Hall Street Association
property. Mr. Gardner was also concerned since his client had
not received analytical data from samples obtained during the
remedial investigation.
Response
The 10 ppm isoconcentration line indicated in the Proposed
Plan is only an estimate of the extent of remedial action for the
sClils. All surface soils contaminated with PCBs at concentra-
ti.ons exceeding 10 ppm will be excavated as part of the soil
re.medial action.
Analytical results from samples, if any, collected from the
Hall Street Association property will be forwarded to
Mr. Gardner, by EPA.
3.2
Comments from Potentially ResDonsib1e Parties
Comment '1
Dr. T. R. West, representing 12 Rural Electric Cooperatives
from the States of Illinois, Indiana, Ohio, and Tennessee, made
the following comments on EPA's Proposed Plan:
A.
Dr. West contends that the onsite incineration of the PCB-
contaminated soils will eliminate the source of contamination
in the ravine area. Natural attenuation by the clay soil and
chemical dispersion of the organic contaminants with time and
distance will reduce contaminant concentrations in the ground
water to the proposed action levels.
Dr. West states that the volatile organics contaminating the
ground water are industrial cleaning solvents and not con-
stituents from transformer oil or oil from other electrical
equipment.
B.
C.
The group of twelve rural electric cooperatives assert that
the transformers sent to MEW by them were sent before the
TSCA regulations became effective in 1979. Therefore, they
have no obligation to cleanup the Site.
5
-------
D.
Dr. West states that based on the information gathered during
the remedial investigation, the water bearing zone tested
does not qualify as an aquifer. It is not possible,
according to this commentor, for a sustaining well to be
developed in this zone. Therefore, there is no public health
or environmental threat to ground water, and no need to
collect and treat ground water from this water-bearing zone.
Response
A.
EPA concurs with the fact that onsite incineration will
eliminate the PCB contamination and any volatile organic
contamination that is present in the soils to be incinerated.
However, the depth to the ground water at the site is almost
40 feet. It is not anticipated that soils will be excavated
and incinerated to these depths. Furthermore, volatile
organic contamination was found in the soils adjacent to the
MEW structure and in the ground water northwest of the ravine
area. This indicates that there may be multiple sources of
volatile organics which are contaminating the ground water.
Onsite incineration of the PCBs will not necessarily remove
the volatile organic compound sources of ground water contam-
ination. Monitoring of the ground water will not actively
reduce the threats posed by the contaminants present.
B.
The question of liability for the contamination at the
site is not pertinent to the remedy selection and this Record
of Decision. Accordingly, this comment will.not be addressed
at this time.
C.
See Response to #1 - B ahove.
D.
MDNR has identified the ground water monitored at the MEW
Site as an aquifer. The information in the possession of
MDNR indicates that there is not a continuous aquiclude in
the bedrock, in the area of the MEW Site, for a depth of
approximately 1,000 feet. contamination in ground water
migrates both vertically and horizontally, which could impact
existing or future drinking water wells. There is no infor-
mation in the record or in Dr. West's letter that refutes the
MDNR data. Construction of deep exploratory borings with
subsequent installation of monitoring wells to be conducted
in the hydrogeological investigation during the remedial
design will provide information about the presence or absence
of an aquiclude in the bedrock in the vicinity of the MEW
site as well as provide data regarding the vertical extent of
ground water contamination. Therefore, EPA disagrees with
the statement "Therefore, there is no public health or envi-
ronmental threat to groundwater, and no need to collect and
treat ground water from this water-bearing zone."
6
-------
(~omment '2
stuart Hunt, legal counsel for Missouri Electric Works,
Inc., submitted the following comments regarding EPA's proposed
plan:
A.
Mr. Hunt indicated that the most glaring deficiency of the
Proposed Plan was that it recommends a remedy for the PCB-
contaminated soils that is not cost-effective when other
treatments are available that are equally protective of human
health and the environment.
B.
Mr. Hunt indicated that the Proposed Plan did not address the
air pollution that would be emitted from the incinerator and
its possible adverse effects to human health and the envi-
ronment and interfere with the ongoing businesses in the area
of the MEW Site.
C.
Mr. Hunt further states that according to EPA guidance con-
centrations of PCBs at industrial sites below 500 parts per
million represent "low threat" and could be addressed with
containment and site security. MEW believes that institu-
tional controls, fencing, asphalt capping and deed restric-
tions would adequately protect human health and the
environment at a far lower cost.
Response
A.
For the reasons set forth in the Record of Decision, the best
balance between the primary balancing criteria identified in
the NCP, including cost-effectiveness, is provided by onsite
incineration. The stabilization/fixation alternative
provided some reduction in the mobility of the PCB-contamina-
tion, it did not reduce the toxicity and actually increases
the volume of PCB-contaminated materials. Its long-term
effectiveness , is less certain as a result of erosion,
possible seismic events and weather variations that may
threaten the integrity of the monolith. The costs presented
for solvent extraction do not include the construction of a
water treatment unit, which could amount to over $1 million.
Again, onsite incineration provided the best balance of
trade-offs, par~icularly with respect to long-term effective-
ness and the permanent reduction of toxicity, mobility and
volume. .
B.
Air pollution from the onsite incinerator is addressed in the
Record of Decision. A pollution control train will be part
of the onsite incinerator. The emissions from the incin-
erator will be monitored frequently to ensure proper
operation. It is unlikely that improper operation of the
7
-------
incinerator would occur with the amount o~ oversight and
monitoring that will be performed. Attempts will be made to
minimize the amount of interference with the business
activities of ongoing businesses, to the extent practicable.
The primary purpose of the remedial action is to cleanup the
site and to remove the threat to human health and the
environment. In accomplishing this directive, some short-
term interference may occur.
C.
The arithmetic mean of the sampling performed at the MEW Site
during the Remedial Investigation is over 500 parts per
million. As such the contamination at the MEW site does not
represent "low threat" concentrations. Construction of
fences, warning signs and an asphalt cap over the contami-
nated area would not be protective of human health or the
environment nor would it met applicable or relevant and
appropriate regulations (ARARs) which is the threshold
criteria that must be met according to the NCP. This
remedial alternative was eliminated from further consid-
eration during the comparative analysis in the Proposed Plan
because it did not meet threshold criteria.
Comment '3
Mr. Thomas Siedhoff, as representative of the MEW's PRP
Steering Committee, submitted several comments on the Proposed
Plan. These comments are summarized below:
A.
The Steering Committee believes that stabilization of PCB-
contaminated soils satisfies the statutory requirements of
CERCLA S121 and meets the selection criteria of the NCP.
B.
The Steering Committee states that the arithmetic mean
concentration of the PCB-contamination within the 10 ppm
isoconcentration line is roughly 522 ppm; the geometric mean
is about 20 ppm within this area. The blended soils will
have an average concentration of less than 50 ppm which would
"logically be considered to be. below the threshold of TSCA
incineration limits."
C.
The Steering Committee believes that incineration is a very
expensive option and feel that stabilization/fixation of the
soils and the long-term management controls for onsite
disposal should be minimal and should not be viewed as a
significant disadvantage.
D.
The Steering Committee states that the ground water is con-
taminated with chlorinated solvents. None of the PRPs sent
chlorinated solvents to MEW and therefore should not be
responsible for the ground water contamination. They feel
8
-------
that the remedial action can and
operable units; one for soil and
ination. They indicate that EPA
ground water remedy.
should be divided into two
one for ground water contam-
should select an appropriate
E.
The Steering Committee state that the MDNR Leaking Under-
ground Storage Tank Guidelines define an aquifer as a ground
water unit having a flow of 5 gallons per minute (qpm) or
more as a "usable" aquifer. The hydraulic data generated
during the RI indicates that the monitoring wells provided
water volumes substantially less than 5 qpm (about 1 qpm).
It questions whether the ground water contamination poses any
future risks to human health or the environment.
F.
While the Steering Committee admits that data gaps exist
regarding the vertical extent of the ground water contamina-
tion and the hydraulic parameters below a depth of 60 feet,
it believes that remediation of the soil contamination will
likely mitigate the source of the ground water contamination.
The existing ground water contamination should be allowed to
attenuate naturally after the soils have been remediated or
the ground water remedy should be selected after the results
of a supplemental hydrogeologic assessment of the site and
surrounding area have been made.
G.
The Steering Committee believes that it would be prudent for
EPA to defer the final selection of a ground water alterna-
tive until a more complete evaluation of the ground water
regime has been performed and a more thorough assessment of
the actual current and potential future risks posed by ground
water are evaluated.
Response
A.
For the reasons set forth in the Record of Decision, the best
balance between the primary balancing criteria identified in
the NCP, including cost-effectiveness, is provided by onsite
incineration. The stabilization/fixation alternative
provided some reduction in the mobility of the PCB-contamina-
tion, it did not reduce the toxicity and actually increases
the volume of PCB-contaminated materials. Its long-term
effectiveness is less certain as a result of erosion,
possible seismic "events and weather variations that may
threaten the integrity of the monolith. The costs presented
for solvent extraction do not include the construction of a
water treatment unit, which could amount to over $1 million.
Again, onsite incineration provided the best balance of
trade-offs, particularly with respect to long-term effec-
tiveness and the permanent reduction of toxicity, mobility
and volume.
9
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B.
EPA expressed its concerns regarding the apparently low value
of the arithmetic and geometric means for PCB-contamination
concentration levels in its comment letter on the Remedial
Investigation report. The calculated arithmetic and
geometric mean identified in this comment represent only
discrete sampling points, most of which were obtained during
RI sampling. The analytical data from EPA composite samples
were not included. It is EPA's opinion that the arithmetic
and geometric means presented by the Steering Committee
underestimate the concentrations of PCBs contaminating the
soils, particularly on the MEW property. The PCB concentra-
tions in the soils, in EPA's our evaluation of the data,
justify selection of the onsite incineration remedy.
The arithmetic mean of the sampling performed at the MEW Site
during the Remedial Investigation is over 500 parts per
million. As such the contamination at the MEW site does not
represent "low threat" concentrations.
C.
The stabilization/fixation alternative relies on encapsula-
tion of the contamination in a stabilized monolith. The
relative low leachability of the encapsulated materials
relies on the significantly reduced surface area available to
the leaching process. As mentioned in the Proposed Plan,
shrinkage cracks or fractures in the monolith as a result of
seismic activity as well as weathering forces will increase
the surface area susceptible to leaching. Over time these
weathering forces could significantly reduce the integrity of
the stabilized mass, thereby making it less effective as a
containment or encapsulating medium. As explained in the
Record of Decision, EPA considers onsite incineration of the
PCB-contaminated soils to be cost-effective.
D.
The question of liability for the contamination at the site
is not pertinent to the remedy selection and this Record of
Decision. Accordingly, this comment will not be addressed at
this time.
E.
Based on the data gathered during the various investigations
at the Site and the information in the possession of MDNR
regarding the hydrogeologic regime in the vicinity of the
Site, it was the opinion of EPA that both remedies can and
therefore should be selected at this time. However, provi-
sion has been made for additional investigation and
monitoring of ground water at the Site during the remedial
design process.
According to the State of Missouri, Geologic Survey, there is
no confining layer, such as a continuous shale bed, in the
vicinity of the MEW Site for a depth of 1,000 feet. This
lneans that there is no barrier between the contamination
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detected in the upper 30+ feet of bedrock and the ground
water being used in the lower portions of the a~ifer.
Therefore, EPA and MDNR believes that the contamination
present in the upper portion of the aquifer does represent a
risk to human health and the environment.
F.
EPA agrees that additional information about the hydrogeo-
logic regime in the vicinity of the Site would be helpful to
effectively design the remedy. A provision for additional
investigation into the ground water conditions, i.e,
horizontal and vertical extent of contamination, direction of
ground water flow, depth to a confining layer, etc. has been
included in the Record of Decision, in the selected ground
water remedy. These studies would be performed prior to the
initiation of ground water treatment.
EPA concurs with the fact that onsite incineration will
eliminate the PCB contamination and any volatile organic
contamination that is present in the soils to be incinerated.
However, the depth to the ground water at the site is almost
40 feet. The volatile organic compounds detected in the
ground water are classified as "sinkers"; which means that
these chemical compounds are heavier than water and tend to
sink to a confining layer and flow along it with dispersion
into the water as they sink. The data at the site indicates
that there may be multiple sources of ground water contami-
nation. The onsite incineration of the contaminated soils
may not remove all source areas and therefore should not be
considered a "fix" for the ground water contamination.
G.
EPA does not agree that the decision regarding the ground
water remedy selection should be deferred. Enough informa-
tion exists from which to select a ground water remedy.
However, EPA will consider additional data gathered in the
hydrogeological investigation during the remedial design
process.
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Unt!~ States
EnViron/il8ntal Protection
Agency
Offic8 01 Solid Waste
Office 01 Solid Wast.
and EI'T'8~enc:y ~8S00ns.
Washington DC 20460
EPA/S30.sw.eg.c:.s
March' 990
-EPA
Environmental
Fact Sheet
TOXICITY CHARACTERISTIC
RULE FINALIZED
The final Toxicity Characteristic rule adds 25 organic chemicals to the eight
metals and six pesticides on fhe existing list o( constituents regulated under
RCRA. The rule also establishes regulatory le'lel$ (or the new organic
chemicals list9d. and replaces the &traction Proc9dure leach test with the
Toxicity Characteristic Leachif)Q Procedure. Generators must comply with this
regulation within six months o( the date o( notice in the Federal Register: small
quantity Qenerators must comply within one year.
BACKGROUND
On June 13. 1986. the Environmental Protection Agency (EPA)
proposed to revtse the existing toxiCity characteristic. one of four
characteristics used by the Agency to identify hazardous waste to be
regulated under Subtitle C of the Resource Conservation and Recovery
Act (RCRA). The proposed rule was designed to refine and broaden the
scope of the RCRA hazardous waste regulatory program. and to fulfill
specific statutory mandates under the Hazardous and Solid Waste
Amendments of 1984.
Under CWTent regulations. EPA uses two procedures to define wastes
as hazardous: Ust111g and hazardous character1stfcS. The listing
procedure Involves Ident1fy1ng indust:r1es or processes that produce
wastes that pose hazards to human health and the environment. The
second procedure Involves Ident1fy1ng propert1es or "characteristics"
that.. If exhibited by any waste. indJcate a potenttal hazard If the waste
Is not properly controlled. Tox!dty 15 one of four characteristics that
must be considered when Ident1fy1ng a waste as hazardous. The others
are IgnJtab1l1ty. reactMty. and corroslV1ty.
The proposed version of the new rule added 38 new substances to the
Toxicity Characteristic 11st: 13 of these constituents are not included in
the final version due to technica1 difficulties in establishing approprtate
regulatory levels. EPA bases all regulatory levels for hazardous
chemicals or. health-based concentration thresholds and a dilut10nl
atterwa.ttDn!a.ctor spedfic to each chemical. A concentration Uu'eshold
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indicates how much of the chemical adversely affects human health.
while the dilution/attenuation factor indicates how easily the chemical
could seep (or "leach") Into ground water. The levels set in the Toxicity
Characteli8t1c rrc) rule were detennined by multiplying the health-based
number by a dilution/attenuation factor of 100.
'The lntroduction of the TC rule in 1986 generated extensive publJc com-
ment on a variety of issues. The TC involves a new "modeUng" approach.
a mathematical computer model. to slmulate what happens to hazardous
waste in a landftll. Results from the TOxiCity Characteristic Leaching Pro-
cedure rrcLP). a new test that Is part of the TC role. are more reproduc-
Ible than results from the old Extraction Procedure (EP) leach test. and
the new test is easier to run.
Following the 1986 proposal. EPA published several supplemental no-
tices in an effort to evaluate and incorporate public comments before ft-
nal.izing the rule.
ACTION
EPA Is finalizing the regulatory levels for 25 of the 38 constituents of
concern that were IdentiBed in the proposed Toxicity Characteristic rule.
Regulatory levels for the remaJ.n1ng 13 constituents w1ll be proposed at a
later date.
A waste may be a 'ie waste" if any of the chemicals listed below are
present in waste sample extract or leachate resulting from application of
the TCLP to that waste. If chemicals are present at or above the specified
regulatory levels. the waste is a 'TC waste." and Is subject to all RCRA
hazardous waste requirements. Regulatory levels established under the
. EP tOxicity characteristic reD"aff1 the same. but require application of the
new test.
Waste generators who have already not1fted the Agency that they gener-
ate other hazardous wastes and who have obtained an EPA Identification
number for their fad11ty are not required by this rule to notify EPA that
they now generate a '1"C waste." Fad11ties that are permitted to treat.
store. or dispose of hazardous waste. however. may require new or modl-
Bed permJts to handle "TC waste." and should contact their EPA Regional
office for more inCormatlon.
Implementation of the TC n.a1e wtlllnJt1al1y be the responslbWty of EPA's
Regional offtces. State hazardous waste programs must modify their
regulations to reflect the requirements of the TC rule before they can be
authortzed for Implementation.
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"
The Jollawfng con.stt.tuents are nDW reguJ.a.ted LI11der the ToxU:t.4J Ch£JTacter1s~ rule. Was U
generators must det.erTTUne the levels present en the1r waste sample extract CT leachate.
based e~r on thetr Jawwledge oj the1r proces~s or by applfcal10n oj the TCLP.
New Conatitueata/fUruJatoryleYe1a
Benzene. . . 0.50 mg/l
Carbon tetrach]or1de . . . 0.50 mg/l
ChJon1ane. . .0.03 mg/1
ChJorobenzene. . . 100.0 mall
Chloroform. . .6.0 mg/1
m-cresoI. . . 200.0 mg/18
o-Cresol . . . 200.0 m &11
p-CresoJ. . .200.0 mg/l
1.4-Dlch1orobenzene...7.5mg/l
1.2.Dich.1oroethane. . .0.50 mg/l
1.1-Dich1oroethylene.. .0.70 mgll
2.4.Dtnftrotoluene. . .0.13 mg/l"
Heptachlor (and
1ts hydroxSde) . . . 0.008 mg/l
Ha:achloro-l.3-butadiene . . .0.5 ma/1
Hexacblorobenune. . .0.13 mgil..
Haac.h1oroethane. ..3.0 mg/1
M~yl ethyf ketone. . . 200.0 mg/J
Nitrobenzene. . . 2.0 mg/1
PentachlorophenaJ . . . 100.0 mg/18-
Pyr1d1ne . . . 5.0 mg/l-
Tetrac.h1oroethylene . . . 0.7 mg/1
Tr1ch1oroethy1ene. . . 0.5 man
2.4.5-Tr1chloropbeno1 . . .400.0 m&I1
2.4.6-TricbJorophmol. . . 2.0 mcJ1
Vinyl chlor1de . . .0.20 mall
\..
Old EP CoD8t1tueata/RefUIatory le.e18
Arsen1c . . . 5.0 mg/l
Barium... 100.0 mg/l
CadmJum.:. 1.0 mg/l
Chromtw::D . . . 5.0 mg/1
Lead. . . 5.0 mg/l
Mercury . . . 0.2 mg/1
Selemum . . . 1.0 mg/1
Silva' . . . 5.0 mg/1
Endnn. . .0.02 mg/l
Undane . . . 0.4 q/l
Methoxychlor. . . 10.0 mg/1
TODphene . . . 0.5 mg/1
2.4-Dtch1oropbenaxycetlc add . . 10.0 mg/l
2.4.5-Trk:hJoropbenaxyprop1Dmc
add . . . 1.0 mg/l
.
, .
Many Underground Storage Tank (uS'O sites are regulated under Sub-
title I of RCRA. The Tox1dty Charactertstic rule will not apply to usr pe-
troleum-contammated media and debris regulated under Subtitle I until
the Agency completes a number of studies of the Impacts of the TC on
these wastes. Dw1ng the study period. usr sites will conttnue to be
regulated under Subtitle I of RCRA.
Usted wastes. unl1ke characteristic wastes such as a 'i'C waste." can be
removed from EPA's lists of hsa7~rdOUS wastes through a process called
. Ito-.m-. and p~re801 concentraUoN cannot be ~erenuat.ed. the total aeeol concentrat1on
Is used. The reguJatmy ICY'eI for total aeeoll8 200.0 mg/L
- QuanUtation I.I.m.It II creet.er than the caJcu1at.ed ~t.ory level. The quanUtat10n 11m1t.
. then:(ore. becomee the regulatory 1eYei.
... The Agency Vr11I propoee a new recuJatDry level for UUa coNt1tuent. baaed on the latest
toX1dty 1nJ'ormatJt)n.
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delisttng. Delistlng determinations are made on a case-by-case. site-
specific basis. Although it is not discussed in the preamble to the TC
rule. the guidance for submitting deUsting petitions will be modified in
the near future to reflect the replacement of the EP leach test with the
TOxiCity Charactertstic Leaching Procedure. Notlftcation of the effective
date for this change will appear in a future Federal Register notice.
Hazardous V\
Information I
US EPA Regie
Philadelphio,~
CONCLUSION .
Based on consideration of 12 affected fndustrfes. EPA estimates that the
Toxicity Charactertstic rule will bring a significant volume of additional
wastewaters. solid waste. and sJudge under the control of its hazardous
waste regulations. The rule will bring a large number of waste generators
under Subtitle C regulation for the first time. and many treatment. stor-
age. and disposal facilities will require new or modified permits to handle
"TC waste."
The Agency strongly encourages industry to reduce the generation of all
hazardous wastes through pollution prevention and waste m.tn1m1zation
practices. For information and publications on pollution prevention op-
tions. contact the toll-free RCRA Hotline number listed below.
TC Impact on Used 011 Regulation
Used oU that Is dJsposed of. rather than recycled or burned for energy
recovery. Is regulated as a hazardous waste under Subtitle C if it exhibits
any of the four characteristics descrtbed above. The Toxic1ty Character-
istic rule adds a number of substances to the toxicity list that may bring
previousJy "nonhazardous" used oU under Subtitle C regulation.
Currently. hazardous used oil that is recycled by being burned for energy
recovery 1s m1n1mally regulated under RCRA (a variety of adm1n1strative
requirements must be met). Used oil tbat Is recycled in any other way Is
currently exempt from Subtitle C regulation. These regulations for re-
cycled oil are not affected by the Toxicity Characteristic rule. The Agency
Is currently determ1n1ng bow best to regulate used 011. and 15 working to
develop standards to ensure proper management of used 011 that may
pose a threat to human health or the enVironment.
CONTACT
EPA 15 distr1buttng information materials to trade associations represent-
ing those industries potent1ally affected by the ToxSdty Characteristic
rule. These mater1als describe constituents of concern specific to each
affected industry. and include compl1ance gwdel1nes for newly regulated
generators. To order copies of these materials. a copy of the Federal Reg-
. tster. notice. or (or further information. contact the RCRA HotJJne Mon-
day through Friday. 8:30 a.m. to 7:30 p.m. EST. The national toll-free
number 15 (800) 424-9346; for the hearing impaired. the number is roD
(800) 553-7672. In Washington. D.C.. the number is (202) 382-3000 or
TDD (202) 475-9652. .
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