United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R05-90/150
September 1990
<& EPA Superfund
Record of Decision
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50272-101
REPORT DOCUMENTAT1ON 1'. REPOATNO. 12.
PAGE EPA/ROD/ROS-90/1S0
3. RecilMnt'a Ac-*on No.
S. Report Da~
4. TIle end SubtIle
SUPERFUND RECORD OF DECISION
Bofors Nobel, MI
First Remedial Action
7. AUlllor(a,
9/17/90
6.
8. Pe,formill9 Organlzedon Repl. No.
t. Performing Orgalnlzedon ...- and Add....
10. Projec1lT..kIWork Unit No.
11. Cont..c~C) or Grant(G) No.
(C)
(G)
12. ~ng Org8niullon *- and Addreu
U.S. Environmental Protection
401 M Street, S.W.
washington, D.C. 20460
13. Type of Repor1 & Period Covered
Agency
800/000
14.
15. Supplementary No...
18. Ab81rac1 (UmI1: 200 _Ida)
The 8S-acre Bofors Nobel site is an active specialty chemical production plant in
Edelston Township, Muskegon County, Michigan. An inactive landfill is also located in
the eastern portion of the site. Onsite wetlands lie within ~the floodplain of Big
Black Creek, which runs through the southern portion of the site. The site overlies a
lacustrine aquifer, a potential drinking water source, which has been contaminated as a
result of site activities. During the 1960s and early 1970s, sludge, wastewater, and
waste liquids from plant operations were discharged into 10 onsite lagoons. Subsequent
investigations by EPA have identified eight of the onsite lagoons as potential sources
of ground water contamination. In 1976, the State restricted wastewater discharge from
the site, and a ground water pump and treatment system was installed to treat
contaminated ground water in the lacustrine aquifer. This Record of Decision (ROD)
addresses remediation of the lagoons, as well as upgrading the current ground water
treatment system. A subsequent final ROD will address other contaminated soil and
complete restoration of the aquifer. The primary contaminants of concern affecting the
soil, sludge, and ground water are VOCs including benzene.
(See Attached Page)
17. eoc-t An8Iy8Ie .. a ... '\.I
Record of Decision - Bofors Nobel, MI
First Remedial Action
Contaminated Media: soil, sludge, gw
Key Contaminants: VOCs (benzene)
b. 1dIn11l8nlOp8n-EndId T-
c. CooA 11 R8\d1Oroup
18. Avell8b111y seal-"
1 t. Sacurlty CI... (11\1. Report)
None
20. SecurIty CI... (11\18 Pafl8)
Nnnp
21. No. 01 P.f188
73
I
22. PrIce
(SH ANSl-Z3t.18)
SH/natrucliOM on Re-
-~-, (4-77)
(Form8riy Nl15-3S)
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EPA/ROD/R05-90/150
Bofors Nobel, MI
First Remedial Action
Abstract (Continued)
The selected remedial action for this site includes excavating approximately 101,000
cubic yards of sludge and berm material highly contaminated with VOCs, treating the
contaminated material onsite using incineration and low temperature thermal desorption,
disposing of the residual ash in an onsite landfill, and treating scrubber water from the
incinerator by precipitation; treating landfill leachate in the ground water treatment
system; excavating approximately 372,000 cubic yards of less VOC-contaminated soil and
sludge and disposing of these wastes onsite in the landfill; pumping and treatment of
ground water using ozone oxidation or a comparable treatment with onsite discharge to
surface water; monitoring ground water, surface water, and air; and implementing site
access restrictions including fencing. The estimated present worth cost for this
remedial action is $70,874,000, which includes an annual O&M cost of $313,000 for 43
years.
PERFORMANCE STANDARDS OR GOALS: Landfilled material must exhibit an excess lifetime
cancer risk of less than 10-6. Chemical-specific soil cleanup levels were developed
based on the type and location of contaminated media within or adjacent to the lagoons
including benzene 410 to 4,500 ug/kg. Ground water cleanup levels are based on proposed
Best Available Technology discharge standards including benzene 5.0 ug/l.
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DECLARATION FOR THE RECORD OF DECISION
SITE NAME AND LOCATION
Bofors-Nobel Site
Muskegon, Michigan
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for
the Bofors-Nobel site, in Muskegon, Michigan, chosen in accord-
ance with CERCLA, as amended by SARA and, to the extent practic-
able, the National Oil and Hazardous Substances Pollution
contingency Plan. This decision is based on the administrative
record file for this site.
The State of Michigan concurs on the selected remedy.
ASSESSMENT OF 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), may present an
imminent and substantial endangerment to public health, welfare,
or the environment.
/
DESCRIPTION OF THE REMEDY
This operable unit is the first of two operable units for the
site. This operable unit addresses contaminated sludges and
soils in the lagoon area, a major source of contamination at the
site. The second operable unit will involve remediation of
contaminated soils in the vicinity of the operating manufacturing
facility and remediation of the contaminated groundwater. The
respon~e action for this operable unit addresses the principal
threa~~~8maining at the site by treating the most highly contami-
nated sludqe. Treatment residuals, less-contaminated sludge, and
soils contaminated, at low levels will be disposed of in an on-
site landfill that will meet the intent of RCRA subtitle C
requirements.
The major components of the selected remedy include:
Excavation and treatment, via on-site thermal treatment, of
approximately 101,000 cubic yards of the most-contaminated
sludge from the lagoon area;
Disposal of approximately 19,000 cubic yards of less-
contaminated sludge, approximately 353,000 cubic yards of
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Upqrading of existing groundwater pumping and treatment
system.
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the
environment, complies with Federal and State requirements that
are legally applicable or relevant and appropriate to the
remedial action, and is cost-effective. This remedy utilizes
permanent solutions and alternative treatment technologies to the
maximum extent practicable and satisfies the statutory preference
for remedies that employ treatment that reduces toxicity,
mobility, or volume as a principal element. Because this remedy
will result in hazardous substances remaining on-site above
health-based levels, a review will be conducted within five years
after commencement of remedial action to ensure that the remedy
continues to provide adequate protection of human health and the
environment.
I~~j
Valdas V. Adamk
Regional Admini
. -~... '....' \.
..--~:...~-~:.
Ii-
J;r;;..k- 11, ~1f9o
Date
-------
STATE OF MICHIGAN
NATVtIAL "IIOURCU r C
THOMAS J ANDERSON
MARLENE J. FLUHARTY
GORDON E GUYER
KERRY KAMMER
ELLWOOD A MATTSON
o STEWART MYERS
RAYMOND POUPORE
at'
~
JAMES J. BLANCHARD. Governor
DEPARTMENT OF NATURAL RESOURCES
STEVENS T MASON BUILDING
POBOX 30028
LANSING. 1.41 .8909
DAVID F HALES. Dtr8CtO<
September 1~, 1990
Mr. Valdas Adamkus, Regional Administrator
U.S. Environmental Protection Agency
Region V, SRA-14
230 South Dearborn Street
Chicago, Illinois 60604
Dear Mr. Adamkus:
Bofors-Nobel Site.
Muskegon County, Michigan
The Michigan Department of Natural Resources (MDNR), on behalf of the State of
Michigan, has reviewed the proposed Record of Decision (ROD) for the
Bofors-Nobel site. The site response has been organized into two operable
units:
SUBJECT:
r
B.
lagoon Area Operable Unit which addresses contamination in the sludges,
lagoons, soils under and around the lagoons, and upgrading of the
existing groundwater pumping and treatment system.
Groundwater and Plant Area Operable Unit which addresses contamination of
the groundwater under the site and contamination in the soils in the
plant area.
A.
This ROQ~cqncerns the f1rst of these two operable units which addrp.sses the
major s~of conta8ination at the site. Michigan concurs with Alternative
4 selectel-tn the ROO. The remedy addresses the principal threat at the site
by treatfD9the lOst highly contaminated sludges and soils by on-site
incinerat1on/low-te8Perature thermal desorption, and upgrading of the existing
extract 10n and treatment system for the groundwater. Treatment res idua 1 s, :and
sludges and soils with lower levels of contamination will be disposed of in an
on-site landfill constructed in accordance with RCRA Subtitle C landfill
requirements.
The selected remedial action for this operable unit will provide protection of
human health and the environment through treatment and engineering controls.
Fl1028
3189
--
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Mr. Valdas Adamkus
-2-
September 14, 1990
It is the department's judgement that this action will significantly reduce or
eliminate the risks posed by the lagoon area sludges and soils.
I look forward to implementation of
Bofors-Nobel Site, and to selection
the site.
cc:
Mr. Jonas Dikinis, US EPA
Ms. Mary Elaine Gustafson, US
Dr. James Truchan, MOHR
Mr. Willia8 Bradford, MONR
Mr. Gerard Heyt, MOHR'
Mr. Roger Przybysz, MONR
.,,?;,.,.a.,*,,~ ,
.
this remedy for the lagoon area of the
and imPl~ion of a final remedy for
sincelelY,
..,
/6
oa~~I~~ -4
Director
517-373-2329
EPA/
-------
v
DECISION SUMMARY FOR THE RECORD OF DECISION
SITE NAME. LOCATION. AND DESCRIPTION
The Bofors-Nobel (Bofors) site is located 6 miles east of down-
town Muskegon on Evanston Road in Egelston Township, Muskegon
County, Michigan (see Figure 1). This 85-acre site includes a
currently operating specialty chemical production facility, an
unused landfill, a currently operating groundwater pumping and
treatment system, and 10 abandoned sludge lagoons. The southern
portion of the site is bounded by Big Black Creek. Pertinent
site features are shown on Figure 2. There are wetlands on
either side of Big Black Creek, within the Big Black Creek flood-
plain. The approximate location of wetlands within the site
boundary is shown in this figure. A lacustrine aquifer underlies
the site and is contaminated from previous site activities. The
existing groundwater pumping and treatment system prevents off-
site migration of the contaminated groundwater into Big Black
Creek. This portion of the aquifer is not currently being used.
A clay till approximately 150 feet thick underlies this lacus-
trine aquifer and separates it from the underlying Marshall
Sandstone, a drinking water aquifer. There appears to be an
upward hydraulic gradient through the till.
Big Black Creek is currently being used for recreational pur-
poses. This includes fishing and swimming. In addition, there
is evidence of transient residences on the south side of the
creek. ~
Approximately 1,800 people live within a 1~25-mile radius of this
site. The primary route of exposure for this population is
through inhalation of contaminated air from the site. Contami-
nated groundwater will not migrate off-site assuming the existing
pumping and treatment system remains operational.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
Lakew~emicals began producing industrial chemicals at the
site i~1960. Throughout the 1960s and early 1970s, ten on-site
lagooft&,were used for disposal of sludge, wastewater, and various
waste liquids. This practice resulted in contamination of the
groundwater underneath the site and, subsequently, Big Black
Creek. Because of this contamination, the State of Michigan
placed various restrictions on wastewater disposal from the site.
In 1976, wastewater from the plant was accepted at the Muskegon
County Wastewater Treatment Plant, and purge wells were installed
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LAKETON RD
CARR I.AKE
Q
CI:
EVANSTON
RD
BOFORS
SITE
~
N
La.
~
~
-~."~"'-'",
..~':~ ~
._""'" ....
~~~..
~~
SUMMIT
RD
"
-------
.,
EVANSTON ROAD
LOMAC PLANT
D
ruQ
G] []
UNUSED
LANDFILL
LAGOONS
BERMS
L.O.U.
BOUNDARY
SOILS AROUNO
LAGOONS
APPROXIMATE
'tYfTLAND
80UNDARY IN
VICINITY OF
AREA 10
-~;~~~~ \.
~
NUMBERS-SOURCE AREAS
Figure 2
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Bofors Industries, Inc., merged with Lakeway in 1977 and with
Nobel Industries in 1981. In 1985, Bofors-Nobel (Bofors) filed
for bankruptcy for reasons including reported environmental
expenditures in excess of $60 million. As part of the bankruptcy
settlement, the state of Michigan received $15 million and the
u.s. Environmental Protection Agency (U.S. EPA) received
$5 million to be used toward site remediation. As a result of
legal action in bankruptcy court, Bofors was allowed to sell the
operating chemical plant to Lomac, Inc. (Lomac). As part of the
sale, agreements were reached between Lomac, the Michigan
Department of Natural Resources (MDNR), and u.s. EPA that Lomac
would not be liable for cleanup of contamination existing prior
to the sale of the plant area property. These agreements allowed
Lomac to operate the plant independently of previous site activi-
ties. The site was nominated for the National Priorities List
(NPL) and was placed on the NPL in March 1989. The Remedial
Investigation/Feasibility Study (RI/FS) was initiated in
August 1987.
Bofors Lakeway, Inc., was a wholly-owned subsidiary of Bofors
America, Inc. (BAI). BAI was a wholly-owned subsidiary of Nobel
Industries Sweden A.B. (Nobel). Nobel is a Swedish corporation.
On May 18, 1990, U.S. EPA sent CERCLA Statute 104(e) information
requests to BAI and to Nobel. BAI responded to those CERCLA
Statute 104(e) information requests in part on June 21, 1990.
BAI filed a supplemental response on August 27, 1990. U.S. EPA
is currently evaluating those responses. u.S. EPA is planning to
fund the Remedial Design (RD) immediately.
HIGHLIGHTS OF COMMUNITY PARTICIPATION
"
The RI/FS and Proposed Plan for the Bofors site were released to
the public in July 1990. These two documents were made available
to the pUblic in both the administrative record and an informa-
tion repository maintained at the u.S. EPA Docket Room in
Region 5 and at the Hackley Public Library in Muskegon, Michigan.
The notice of availability for these two documents was published
in the Muskeaon Press on July 21, 1990. A public comment period
was he., ",from JUly 23 through August 23, 1990. In addition, a
publi-" . ing was held on August 1, 1990. At this meeting,
repre ... .... *ives from U. S. EPA and MDNR answered questions about
probl . *,-the site and the remedial alternatives under consi-
derati8~~: A response to the comments received during this period
is included in the Responsiveness Summary, which is part of this
Record of Decision (ROD). This decision document presents the
selected remedial action for the Bofors site in Muskegon,
Michigan, chosen in accordance with CERCLA, as amended by SARA
and, to the extent practicable, the National Contingency Plan
(NCP). The decision for this site is based on the administrative
record.
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SCOPE AND ROLE OF OPERABLE UNIT WITH SITE STRATEGY
As with many Superfund sites, the problems at the Bofors site are
complex. As a result, U.S. EPA organized the work into two
operable units (OUs). These are:
o
Lagoon Area Operable Unit (L.O.U.): contamination in the
sludges, in the lagoons, in the soils under and around the
lagoons, and upgrading of the existing groundwater pumping
and treatment system.
o
Groundwater and Plant Area Operable Unit (GW/PA O.U.):
contamination of the groundwater under the site and contami-
nation in the soils in the plant area.
This ROD concerns the first of these two operable units. This
operable unit addresses the principal threat through source
control. The location of the L.O.U. is shown in Figure 2.
As shown in Figure 2, the L.O.U. includes eight of the 10 lagoon
contaminant source areas investigated. The remaining two lagoons
did not contain detectable levels of contamination. The southern
portion of the L.O.U. is bounded by a groundwater extraction
system that controls the groundwater contamin~nt plume.
This area of the site poses a principal threat to human health
and the environment because of the risks from contaminant migra-
tion from the sludges and soils into the lacustrine aquifer
directly under site, that is a potential source of drinking
water. The contaminated groundwater, if it discharges into Big
Black Creek, also poses risk from ingestion of contaminated creek
water. There is also a threat because of the risks from inhala-
tion of volatilized contaminants from the sludges and soils. The
purpose of this response is to reduce contaminant migration into
the groundwater, surface water, and air, and prevent direct
contact with the contaminants.
SUMMARY OF SITE CHARACTERISTICS
The Rf~tncluded the following tasks:
o
o
o
o
o
o
o
o
o
o
Lagoon sludges and soils characterization
Plant area soil characterization
Air sampling and analysis
Surface water and sediment characterization
Surficial soil characterization
Aquifer characterization
Groundwater sampling and analysis
Wetlands survey
Baseline risk assessment
Treatability studies
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The results are summarized as follows.
Contamination and Affected Media
The lagoon area sludges and soils and the groundwater showed
detectable levels of contaminants related to the site. The
surface water sampling and analysis showed no detected contamina-
tion. The air analysis indicated contamination only from the
operating plant. Therefore, only a summary of contamination for
the lagoon area sludges and soils and the groundwater is pre-
sented.
Laaoon Area Sludaes and Soils
In the lagoon area, 10 potential source areas were identified.
In these 10 source areas, the sludge from the lagoons, the soil
beneath the lagoons, and the soil around the lagoons were sampled
and analyzed. The organic compounds detected for the lagoon
sludges and soils beneath and around the lagoons are presented in
Table 1. As discussed previously and as shown in Table 1, detec-
table levels of contamination were found in eight of the
10 lagoon areas. These source areas were subdivided into four
possible subareas: lagoon sludge, contaminated soil beneath the
lagoon sludge, contaminated soil around the lagoon sludge, and,
in some cases, a berm. These source areas and subareas are sho~
in Figure 2. The source areas were subdivided because the magni-
tude of contamination varies considerably among the eight source
areas and their subareas. From a treatment standpoint, risks
were calculated for each source area and subarea separately to
aid in selecting the most cost-effective remedial alternatives
which provide the greatest protection of human health and the
environment. Contaminated soils around the lagoons were identi-
fied using results from a 1-acre grid sampling interval; this
explains the irregular source area configurations shown in the
figure. The compounds of concern developed from the baseline
risk assessment are listed below:
o
o
o
o
o
o
Methylene Chloride
B~.ne
3 j-t""~D1chlorobenz idine
Aniline
Aa.oJ:Mmzene
Benaidine
(DeS)
These six compounds of concern were chosen because they are
highly toxic and drive the risk assessment for this site.
Methylene chloride, DCS, aniline, and azobenzene are potential
human carcinogens. Benzene and benzidine are known human
carcinogens.
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Unlls: ppb TABl£ I
SUMMARY OF MAXIUUM lAGOON SlUDGE AND SOIl COMPOUNDS AND CHEMICAlS
OAGANIC COMPOUNDS
lAGOON I lAGOON :s lAGOON 5 lAGOON 8
Sl sa SA B Sl sa SA B Sl sa SA B Sl sa SA B
1 U81hvl8n" r.hInridA 0 0 N" .. .. 10 IN" 0 4 4 IN" 0 ;;;;n In IN" 1'100
hi. 10 0 N& 0 0 ,.. NA 0 0 0 INA 0 0 0 INA 0
Acelone 70 N& 10 0 0 NA 0 0 0 NA 0 0 0 INA 0
BenzeM 0 NA 0 980000 130 NA 0 23 0 NA 0 0 0 NA 0
2-Bulanone '-. 0 NA 0 0 0 NA 0 0 0 NA 0 0 0 NA 0
Eth-'... Ia.- " 0 NA 28 0 0 NA 0 0 0 NA 0 9200 0 NA 4.1IlOO
T"""'" 1_' 170 N& 44eo 1100000 0 NA 0 11 3 NA 0 130000 0 NA 1e5.mo
X"""" "'mnl I.- 38 NA 1110 0 0 NA 0 14 0 NA 0 !IIIIIOO 1200 NA I"",,""
2-chloroanllln8 1- 2300 NA 130 000 220000 270000 3500 0 0 0 ~ 0 220M 21000 ~ 11 000
3 3' -Olchlorab8ru1d1n8 1- 0 21000 5000 830000 1100000 2700000 0 930000 33000 15QOQO 0 21000 390000 I~ 10500
12.4-Trlchlorab8nz- 0 0 NA 0 0 3:10 0 0 0 0 150 0 0 0 150 0
Bls12-c I.. -
-dIaI_-I-01dde 0 0 NA 1500000O 340000 450000 0 13000 0 8600 0 130000 81000 9800 385 000
3 3' -DIchIar-.zldlne '-'*8 I_ :MIIO NA 32 500 260000 93000 0 0 950000 52000 0 0 100000o 264000 0 500 000
(3-ch1orophenyl)(4-C~ 3000lIO MOO NA leo,ooo 8100000 1800000 2ll00OOO 0 330000 2BOO 11000 0 1300000 280000 II 000 850,000
.me\'->0n8
Aniline 0 1180 NA 0 0 9200 5:10 0 0 0 0 0 0 0 0 0
Alab8n..... 0 113 NA 0 1200000O 100000o 99000 0 110000 5500 3800 0 880000 220M 3800 340 000
Ben.ldlne 0 0 0 0 3400000 5I10OOO 410 0 0 2100 0 0 10000 1800 0 :l!looo
AlINI Ben- _IS 0 0 NA 0 0 148000 48l1OOO 0 0 0 0 0 123000 88400 0 81500
AloJNberu- 0 0 NA 0 890000 480000 170000 0 0 0 0 0 0 0 0 0
Sulfur 0 5100 NA 0 0 0 0 0 0 0 0 0 0 0 0 0
_blSI2'melhun-Benl8ne 0 0 NA 0 I.. 0 0 0 0 0 0 0 0 0 0 0
lAGOON 7 LAGOON 8 lAGOON 8 lAGOON 10
Sl sa SA B Sl sa SA B Sl sa SA B Sl sa SA B
Math""'na Chloride 18 0 0 0 1200 0 0 800 0 0 0 0 0 0 0 0
T et.achlor08lhulane 0 0 82 0 680 0 0 340 0 0 0 0 0 0 0 0
Acetone 0 0 0 0 0 0 0 0 81 0 0 0 0 11 0 0
Benl.ne 0 0 0 0 2800 0 0 1400 890 0 120000 0 8 8 0 4
2.Butanona 0 0 0 0 0 0 0 0 25 0 0 0 0 0 0 0
Elhvtban..n. 0 0 I 0 0 0 0 0 0 0 0 0 0 0 0 0
Toluene 0 0 0 0 1- 0 0 40 000 1200 18000 18QOOOO 0 8 2tO 0 5
X"""'""omDI 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
2-ch1oroanH1n8 0 0 240 0 12000 12000 1800 8000 2300000 58QOO 38QOOO 0 24000 4300 0 12000
3 3' .00001orab8n.1dIna 260000 10000 150000 0 1500000 90000 680000 150 000 1100000o 18000 180000 0 2900000 1100 380000 1 450 000
1 24-Trlchloroba",- 0 0 0 0 1100 1100 0 3550 83000 0 250000 0 0 0 0 0
8IsO-chlornnt--.ull-dIaI...-I-oxlda 82000 0 0 0 0 0 1100 0 0 0 45000 0 0 0 0 0
33' -Olchloroban.ldine - 100000 5100 0 0 1100000 13000 0 850 000 2300000 0 1800 0 :I!IOOOOO 113200 110000 1 150 000
(3.chIorophanyt)(4-chlon>p/l8nyt) 520000 \MOO 64000 0 28000 18000 34000 13,000 0 0 8200000 0 180000 9300 88000 85,000
-me\'->0n8
Aniline 0 0 0 0 1100 0 350 850 '3800000 Il8OO 0 0 '1100 3400 350 850
AlDban.... 220M 0 130 0 33000 4300 3400 18500 8200000 14000 780 0 230000 ~ 3400 115000
Ben.ldlne 0 0 0 0 13000 0 0 8500 '1300000 5500 1300 0 '13000 2200 0 8500
Alkyt Ben.... _IS 0 0 0 0 14 7000 147000 107000 73,500 0 0 14IIQOOO( 0 0 4400 0 0
0
Alo"",,",n.e.. 0 0 0 0 0 0 0 0 0 0 J8000 0 85000 10000 0 42 500
Sulfur 0 8300 0 0 0 0 0 0 0 0 1500 0 0 0 0 0
1 l' -SunonvlblsI2-melhvtl-Be"'ene 0 0 0 0 0 0 0 0 0 0 0 0 82000 0 0 41000
SL: Sludge.
58: Soil benealh lagoons
SA: Soil around lagoons.
H. Berms
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The Toxicity Characteristic Leaching Procedure (TCLP) was
performed on selected lagoon area sludges and soils to evaluate
the potential mobility of metals in the waste material. The
results of TCLP testing were compared to TCLP standards which can
be used as a measure of metal mobility. The concentrations of
metals in the waste were found to be below the TCLP standards.
Therefore, metals in the sludges and soils are not anticipated to
be compounds of concern at this site.
As discussed previously, these lagoon area sludges and soils are
a major source of contamination to the groundwater under the site
and, therefore, a source of contamination for Big Black Creek if
the groundwater pumping and treatment system is turned off. The
lagoon sludges and soils are also a potential source of contami-
nation to air in the vicinity of the site.
The volume of each lagoon subarea was estimated using data
generated during Phase I and II RI activities. The volumes and
surface area associated with each lagoon subarea are shown in
Table 2. The volumes for the soils beneath the lagoons include
material extending from the bottom of the sludge to the average
water table depth. The soil volumes around each lagoon were also
calculated using a depth of contamination of five feet in each
area, except in the area between Lagoons 6, 8, and 9. In that
area, the soil around the lagoons is assumed to be contaminated
to the water table, because of the proximity of the lagoons to
each other and possible overlapping of the lagoon boundaries.
The assumption of contamination only in the top 5 feet for the
rest of the soil around the lagoons is bpsed on evaluation of the
contaminant transport mechanisms by which the contamination
migrated to these soils. These soils are estimated to be
contaminated by surficial mechanisms such as trackout and
airborne contamination. This assumption will need to be verified
during the remedial design. The berm volumes were calculated by
direct measurement off the site topographic map and only include
material above grade. Volumes calculated for soils around the
lagoons are based on limited information and should be considered
as approximate values only.
ApproXtii~.lY 454,200 yd3 of total contaminated media is
estimat~.~o be at this site. Approximately 22 percent
(101,500yd3) represents contaminated sludge; 34 percent
(156,200 yd3) represents contaminated soil beneath the lagoons;
39 percent (178,500 yd3) represents contaminated soil around the
lagoons; and 4 percent (18,000 yd3) represents contaminated berms
around the lagoons. The volume of contaminated media may be
further refined prior to remedial design.
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TABLE 2
SOURCE AREA VOLUMES (yd3)
BOFORS SITE
Muskegon, Michigan
Soil Soil Percent
Source Beneath Around Total of Total
~ Sludqe Berms Laqoons Laqoons Volume Volume
1 3,400 300 9,300 7,700 20,700 L6
3 7,600 0 10,700 3,900 22,200 L9
5 8,000 0 14,400 6,300 28,700 6.3
6 3,400 2,300 5,400 17 , 900 29,000 6.-l
7 7,000 0 26,400 12,600 46,000 10.1
8 28,400 5,500 28,400 14,400 76,700 16.9
9 9,600 0 30,500 33,1.00 73,200 16.1
10 34,100 9,900 31,100 82,600 157,700 3Li
Total 101,500 18,000 156,200 178 ~500 454,200
Percent
of Total
Volume 22.3 4.0 34.4 39.3
Note: Soil volume around the lagoons \oIas calculated assuming only the top
5 feet of soil is contaminated.
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Groundwater
Monitoring and purge wells were sampled and analyzed during the
RI. The organic compounds detected in the groundwater are
presented in Table 3. The extent of contamination in the ground-
water appears to be bounded by the plant area to the north and
the groundwater pumping and treatment system to the south.
Contaminated groundwater at the site appears to be captured by
the groundwater pumping and treatment system. At the present
time, approximately 1 million gallons of groundwater per day is
collected by the existing groundwater pumping and treatment
system and is pumped to a PACT? treatment system owned by Lomac
that also treats Lomac wastewater. The treatment effluent is
discharged to the Muskegon County Wastewater Treatment Plant.
Based on historical data and groundwater modeling, if the
groundwater pumping and treatment system is turned off, the
contaminated groundwater will discharge into Big Black Creek, and
the creek will become contaminated.
Potential Routes of Miaration
Potential routes of migration and contaminant fate and transport
were evaluated for the Bofors site. Based on this evaluation,
the most significant pathways for release of contaminants at the
Bofors site are through the air, surface water, and groundwater
pathways. The Phase I baseline risk assessment indicated that
the risks associated with ingestion of the sludge and soils was
significantly less than the risks assoc~ted with the ground-
water, surface water, and air pathways.. Fate and transport
mechanisms are summarized below for each of these three pathways.
Air Pathway
Contaminants can be released to the air in two ways, either by
particulate or volatile emissions. Risks from particulate
emissions were estimated for exposure by inhalation. These risks
were estimated as approximately 100 times less than the risks
from.i~lation of volatile emissions. Therefore, volatilization
appear.~tabe the primary release mechanism to the air pathway
from tb. lagoon area sludge and surficial soils surrounding the
lagoons. Benzene, methylene chloride, and azobenzene are classi-
fied as highly volatile compounds and may readily volatilize from
the sludge and contaminated surface soils. Aniline may also
volatilize from the sludges, but to a lesser extent, and DCB and
benzidine may volatilize to a limited extent. Even though these
moderate and low volatility compounds may volatilize to a lesser
degree, there may be significant mass loading to the atmosphere
because of the large surface area and high concentrations of
these compounds in the lagoons. Modeling of emission rates and
contaminant transport via the air pathway have shown that the
lagoon areas, due to their considerable surface area, present a
-------
PIIQ8 I 01 !I
TABlE 3
SUMMARY OF DETECTED GROUNDWATER COMPOUNDS
Bolan SIt.
Mu8Ugon, MIchigan
JunelJuIy 11181
VOlATIlE 0FI1ANIC CDUPOUNDS
Un,,: mg/IIg IJIPmI
~ -+tr~ WC2" WC27" lWI ~-2!L~~ ~~~.2!!. ~~ ~~
H8Ioaen818d V""'1I88
C8rban 0I8uIIId8 . ' .
- - ~~- .. -- .. .. 1000 .. .. .. -- .. .. -. .. .. - -
~ .. - - .. .- .. .. - 820 .. 2~ .. .. .. .. .. .. - -
1,2.0IchIcx8Ih8n8 - - .. .. .. .. .. -- .. .. 110 -- !i!i .. -- .. .. .. -
1,2-Dk:h1o
-------
20111
T AIII.E 3
SUMMARY OF DETECTED GROUNDwATER COWI'OUNDs
Boba SIIe, MutIIegon, MIdIIg8n
..Iun8I.IuIy, 11188
SEMIIIOlATIlE ORJANIC COMPOuNDs
UnII8: rng/Irg (ppm)
-';;J
n'" "0 . .'" WC2" WC21. lWI lW3 lW4 PW31 PW33 PWJ8 PW41 uwo.. UWIDO. t/NI1
11 ":, ,- .
H8Ioa8n818d SenWoIaIIIn "'I~'~ .
~-r '.r
. f .
2-Ch101081.... NDtI ...... NO-I4J """"3000 1200 130 110.1 13.1 1300 114 3CIOO 4.1
4~
1.2-D1cNooot....,z- «10
3,3'-DIchIoxabenzId Nl).1.., 83OJ- 1IlOO 440 22J 80J 1110 400 3.1
1.2,'" Trlchbob8nz-.. NO-3OJ CI8J
3,3'-DIctIIorobenzI........ Nl).12J 14OJ-aOJ 8IIOJ 24.1 CIIIOJ 880J 2IJOOJ
3,3'-DIchIoIabenzId '-ner fconI'd).. 88J IIIOJ
13-0lIo.......... oyI) Of 14-<:h1orophen~M8Ih8nane.. NO-1OQJ
T rIchkxo- 1 1JfOPefI8 '-ner
NontIaIoQenaI8d SemIvoI8I11n
Ac.naphthe... 20
~ 21
Aniline 8800-10000 ICIOO 64J
AnUv- 14.1
Azobenz- IIIJ 20.1
Benzidine NO-IIOJ 88 240 230
Benzol8j~ 19J
B8nzol8j~ 230
~
Benzyt Alcohol :IJ
8Ia(2-E1hylhexyl)f'h1h81818 NO-I.I No-l88 IJ8.2.J8 400QJ
ChIyMne 19J
DIbenzohnn IIIJ
DImeChyI PhIh8I8I. NO-4J 12.J 4.1 120.1
Dl-n-BuIytphthaIeI
FIour..u- IIIJ
Flour.... IIIJ
bophofone 114.110 450 1400 !)JJ 280
2.MelhytnaphlhaJene ~ 12.J 8J
2-Melhyfphenol 13.1.410 ND-a2J !)JJ I1J
4-Methytphenol No-I10 :IJ
Naphthatene 20.1-650 22 t3J
-------
301&
TABlE 3
SUMMARY OF DETECTED GROUNDWATER COMPOUNDS
BoIoI8 SIIe, Muobgon, MIchIgan
J~1I88
SEMIVOlAT1lE 00MP0UND8
U"': mg/IIg (ppm)
" "
,
FI8Id oJ (~
. ~
..... ~t.f: r WC2" WC27" lWI lW3 lW4 PW31 PW33 PW311 PW41 MWI)4" MWOII" tIW7
... If"
N-Nllr08O-Ol-n-Propyt8mlne
~- 18J
Ph8naI NI).aJ l70J
Pyr8ne 27
1,1' -OIphenyI 2,2-0IamIne"" 870J
4-U8IhyI-3-pen1en-2-one ND-17OJ
4-Hydroxy-4_hyl-2-penI8non8"" ND-18OJ
3,3,11- TrIm8II1yIcydohexanone" ~ 430J 11000J 32000J 11IOJ
Trtmp 18om8f(8)" 100J 5&OJ 50QJ 88
Trtmp lIom8r(a) (conl'd)" 34O.J 200QJ 1400J 34QJ
2,3-Dlhydfodlmethyl-1 H-'nd8ne" ND-42J
IlenZ8088C8.k: Acid" ND-14OJ
I-Melhylm8phlh8lene" NI).49QJ
N,N-DIme1hyllOfmamlde"" ND-1!!OJ 45O.J
Dlmelhylbenzeneaml... laome," ND-I2OJ 780J
1,2,3-Benzolhladlezole &7OJ-I3OOJ
I-MeIho"Yf1ll.obenze... borne,." ND-22OODJ 300J
SuI...." 18OJ-I4OOJ 1800J
1,2,4-TrtlhIoIane" ND-42OJ
1,3,~TrtI~"" ND-I00J ,
Melhoxybenzeneamlne I.......,." 21 OOOJ
2-Hydfo~""
Dlmethy1m8phlh8lene" " ND-!i2J
-------
40111
TA8l£ 3
SlA8MR'( OF DETECTED OROUNOWATER COMPOUNDS
EIaIora 81., MuIIIegon, MIchIg8n
J~8B8
SEMIYOlATILE OOMPOUNDI
Unb: mg/IIg CPPmI
'.'
~ MW41 MW!I1. MW84. MW81. MWI02" MWI03. MWI04. MWI~. MWI06. MWllle. MW110
..~. ';:r- ,', .;
Ha1a118n818d s.m~ ..,. ":" :. ,." f
2~". 41 '! 780 13OJ.13OOOJ 3.1-100 410-1800 ..1800 12-GOO
40110raen111n8 IIJ NI).42J N[)'23 N[).14J
1.2~
3.3' -DIc:I1Iooab8ru 3J N[).2(IO NO.JIIO 2&-140 12J-2eO
1.2,4- TrIchIorobellz- NO-48J
3,3' -Dlc:hlarab8nZtd1n8 18am8f". NO-32OJ 21J N[).8IIOJ N[).!IOOJ N[).1000J
~QfI4~~" N[).2!IJ
Trlchloro+prapene I8arI* N[).2!IJ N[).38J
NcInh8IaII8n8I8 S8nWoI8III88
Acen8phIh8n8
Ac8n8phIhyI8n8
AnIlIne ND.78 N()'23
An1hracene
Azabenz-
Benzidine 14G-24OJ ND-6J 35J.~ 100-1300 71-890
Benzo(ajAnUu_ne
BenzolajPyra...
8anlyI Alcohol
Bb(2-Elhylhaxyl)PhlhaIaI8 4000J N[).2J ' NO-2.I N[).5J NO-I ClJ IJB,2JB ND-8JB N().3J
a..y.-
Dlbenzaluran
Dlmelhyt PhIhaI8J8 2JB
Dk>-8u1ytph1h818 N[).5J ND.4JB
FIaufanI'-
FIaur-
~one N[).3J
2-Malhy1naph1h818n8 IIJ
2-u.thy1phana1
4-MeIhy1ph8naI
Naphlhalena 1301
Nd.abenzene 2J
-------
lIofS
TABlE 3
SUa&tARY Of DETECTED GR:XJNOWATER COMPOUNDS
BoIors SIt', Mu8bgon, IoIichIg8n
JUI18/JuIy, 1988
BEUMJlATI..E ORGANIc: CXU'OUN08
UnII8: mg/IIg IPPmI
.""
~
MW41
~1"
MW84" MW111" MWI02" MWI03" MWI04" MWI011" MWI06' MWI08" MW110
N[).I40
81J.32OOJ 14OJ-04OJ N[).35OJ
Phen8ntIII8n8
Phenol
Pyr-
1,I'-OIphenyt 2,2.DI8mIn8""
4-Melhyt-3-penlen-2-one
4-HydrO"Y-4-m8Chyt.2-......--""
3,3,:>- T.-hylcydoh8xanone"
TIImp 18om8f1a1"
TIImp e-n.rlsllconrd)u
2,3.Dlhydrodlm8lhyt-IH-Ind8n8"
N[)'31J
N[).I9J
Benz--Ic: Acid"
I-Melhytmaphlhal8ne"
N,N-DimelhytloonamIde'"
Dimelhy\b8nz....emine ~"
Hl).34O.J
1,2,3-Benzofhledlazol8
I-Melho"Y""'obItnze... ...........
SuIfu...
1,2,4-Trlthlolan."
t.3.5-T.hhlane..
MeIho>
-------
significant source of volatile contaminant transfer to the air.
Even though air analysis indicated contamination only from the
operating plant, sampling and analysis of this medium contains
uncertainties.
Photolysis, or the breakdown of compounds through exposure to
light, may also be a loss mechanism for benzidine, azobenzene,
and DCB in the sludge and surficial soils. This mechanism may be
partially responsible for the general absence of benzidine in the
surficial soils. However, the breakdown products from photolysis
of these compounds are hazardous. Oxidation may be a loss
mechanism for benzene, benzidine, and aniline, especially in the
lagoons with high iron content such as Lagoons 3 and 9.
Groundwater Pathway
Another contaminant migration route is through the groundwater
pathway. contaminant release to the groundwater has occurred
from the lagoon sludge, soils beneath the lagoons, and contami-
nated soils around the lagoons due to infiltration of water
through these media into the groundwater.
Sorption significantly decreases the mobility of azobenzene and
DCB, especially in the sludge, because these compounds strongly
sorb to organic material. This may be the reason these chemical
are currently present in such large concentrations in the lagoon
sludges. Methylene chloride and benzene sorb to the sludge but
less strongly. Benzidine and aniline do not appear to strongly
sorb to lagoon sludges. Sorption has a lesser effect in soils
beneath the sludge due to the low organic content of these soils.
However, even if soils have low organic content, sorption may be
significant for DCB and azobenzene because of the high affinity
of these compounds to even small amounts of soil organic
material.
Dissolution and leaching of compounds from the sludge and soil
appear to be the primary transport mechanism to the groundwater
in the upper lacustrine aquifer. The contaminated groundwater in
this ~~fer does not appear to be a potential source of contami-
nants"t8~th. Marshall Sandstone drinking water aquifer due to the
upwar«~.!draulic gradient through the clay till that underlies
the up,.* lacustrine aquifer. Furthermore, diffusion of contami-
nants through the till is expected to be extremely slow.
Surface Water Pathway
During the RI, no surface water runoff was observed. The primary
route of contaminant release to the surface water appears to be
groundwater discharge. As noted previously, contaminated ground-
water is not presently being released to Big Black Creek since i~
is being intercepted by the groundwater pumping and treatment
system. Therefore, groundwater discharge is not considered a
-------
potential route for migration as long as the groundwater pumping
and treatment system is in operation. However, past site condi-
tions and computer modeling performed for the baseline risk
assessment have shown that, if the groundwater pumping and treat-
ment system is turned off, groundwater will be a major contamina-
tion migration route to the surface water.
Potential ReceDtors
Populations that could be affected, if exposed, include:
o
Industrial workers (Lomac, Sun Chemical, Eagle, commercial
facilities north of Evanston Road).
Residents on Wolf Lake, Laketon, Carr, Evanston, Mill Iron,
Summit, and Ravenna Roads within 1-1/4 miles of the site.
Residents of the trailer park to the northwest of the site.
Transient residents on the southern side of Big Black Creek.
Residents using groundwater or surface water at the site at a
future date.
o
o
o
o
Environmental areas that could be affected, if exposed, are
primarily Big Black Creek, the wetlands around Big Black Creek in
the immediate vicinity of the site, down-stream surface water
bodies, and wildlife associated with these areas.
SUMMARY OF SITE RISKS
Human Health Risks
,
Contaminant Identification
The media of concern in this operable unit are the contaminated
sludges and berms in the disposal lagoons and the contaminated
soils around and under the sludge lagoons. As discussed
previously, six contaminants of concern were identified in the
baseline risk assessment from a list of 27 organic compounds
detected in the RI. These compounds are:
o
o
o
o
o
o
Aniline
A%o6enzene
Benzene
Benzidine
3,3'-Dichlorobenzidine
Methylene Chloride
(DCB)
The concentrations of these compounds of concern that were used
for the risk assessment are presented in Tables 4 (air),
5 (groundwater), and 6 (surface water). The maximum concentra-
tions were used during the risk assessment to develop risks for
this operable unit.
-------
TABLE 4
ANNUAl AIR CONCENTRATION
(ug/m3)
Bofors Site
Muskegon, Michigan
(AzImuth - 0)
Receptor: r '" 402.34m '.'
Azimuth - 0 ,\
'i
f .
;'
'.
Compound ~1 Lagoon 3 Lagoon 5 Lagoon 6 Lagoon 7 Lagoon 8 Lagoon 9 Lagoon 10
SLUDGE ONL V
Methylene Chloride ND ND 3.8E-03 3.7E-02 1.2E-02 1.3E.o1 NO NO
Benzene ND 1.1E+00 3.8E-03 NO NO 8.0E.o2 8.4E-02 3.1 E-03
3,3' -Dlchlorobenzldlne 2.6E.()5 4.9E.()5 3.3E.05 1.0E.Q5 4.4E.05 6.6E.05 1.6E.04 5.0E.05
Aniline ND ND ND NO ND 6.6E.o2 7.7E +00 5.0E.o2
Azobenzene ND 6.OE + 00 5.4E.o1 4.8E.o1 2.4E.o1 4.8E.o1 1.3E+01 8.6E.o1
Benzidine NO 2.4E-03 ~ 4.9E.04 ~ 1.2E-03 5.2E-03 8.2E.04
Total 2.6E.()5 7.1E+00 5.5E.o1 5.1 E.o1 2.5E.o1 7.6E.o1 2.1E+01 9.2E.o1
SOIL BENEATH LAGOONS
Methylene Chloride ND ND 6.3E-03 NO NO NO NO NO
Benzene ND 1.8E-02 NO NO NO NO NO 5.5E-03
3,3' -Dichlorobenzidine NO 3.6E.05 2.1E.05 1.4E.05 3. 1 E.o& 3.0E.Q5 2.9E.05 2.4E.05
Aniline 4. 1 E..02 2.2E.o1 NO NO NO NO 2.5E.ol 1.1E.ol
Azobenzene 2.1E-03 2.5E +00 1.4E.ol 1.3E.o1 ND 1.7E.o1 8.1E.o1 7.4E.ol
Benzidine ND 1.4E-03 4.2E.04 3.9E.04 ~ ~ 7.4E.04 6.2E.04
Total 4.3E..02 2.7E +00 1.5E.o1 1.3E.o1 3.1E.o& 1.7E.o1 1.1E+00 8.6E.o1
BERMS
Methylene Chloride ND NP NP 7. 1 E.o2 NP 1.2E.o1 NP NO
Benzene ND NP NP ND NP 1.0E.o1 NP 2.4E-03
3,3' -Dichlorobenzldine 7.9E.06 NP NP ' 1.3E.05 NP 6.2E.05 NP 2.6E.05
Aniline ND NP NP ND NP 1.8E.o1 NP 1.7E.o2
Azobenzene ND NP NP 8.1E.o1 NP 2.6E.o1 NP 6.4E.o1
Benzidine ~ NP NP 5.5E.04 NP ND NP NO
Total 7.9E.06 NP NP 8.8E.o1 NP 7.2E.o1 NP 6.6E.o1
SOIL AROUND LAGOONS
Methylene Chloride ND ND ND ND ND ND ND ND
Benzene ND ND ND ND ND ND 1.1E+01 NO
3,3'-Dichlorobenzidine 1.0E.04 2.7E.05 5.2E.05 8.4E.05 8.SE.05 2.1 E.oS 6.1E.05 2.8E.04
Aniline ND 1.4E.o2 ND ND ND 8.4E-03 ND 9.0E.o2
Azobenzene ND 2.9E.o1 1.SE.o1 2.6E.o1 1.4E-02 4.5E.o2 6.9E.o2 7.1E.o1
Benzidine ~ 1.2E.04 ~ ~ t:!IL- ~ 6.1 E.04 NO
Total 1.0E.04 3.1E.o1 1.5E.ol 2.6E.o1 1.4E-02 S.3E.o2 1.1E+Ol 8.0E.o1
ND: Contaminant not detected in sample(s) from that lagoon.
-------
TABLE 5
GROUNDWATER CONCENTRATIONS OBTAINED FROM THE AT 123D MODEL (PPM)
Bofors Site
Muskegon, Michigan
Unite: ppm
Compound lagoon 1 . Lagoon 3 lagoon 5 lagoon 6 Lagoon 7 lagoon 8 Lagoon 9 Lagoon 10
SOIL AND SLUDGE .r
Methylene Chloride O.OE +00 Q.GE +00 3.7E.()6 2.3E-G4 5. 1 E-as 1.9E.OJ O.OE+OO O.OE + 00
Benzene O.OE +00 e.2E~1 3.4E.()6 O.OE +00 O.OE + 00 4.0E.OJ 4.5E~ 3.4E.Q6
3,3'-Dichlorobenzldine UE-G4 8.3E~ 1.1E~ 2.2E.OJ 8.3E~ 2.6E~ 1.0E+00 3.5E.Q2
Aniline 2.5E.OJ O.OE+oo O.OE + 00 O.OE+OO O.OE +00 O.OE + 00 2.1E+00 1.3E.Q2
Azobenzene 8.5E-G4 7.5E-G4 8.5E~ 1.8E-G4 3.8E~ 2.2E.OJ 1.6E~ 2.9E-oJ
Benzidine O.OE + 00 1.0E+00 1.1E.03 1.6E-G4 O.OE +00 O.OE + 00 1.3E.Q1 3.9E.Q2
SLUDGE ONLY
Methylene Chloride O.OE +00 O.OE +00 1.5E.()6 2.3E-G4 5.1E.Q6 1.9E.OJ O.OE+OO O.OE +00
Benzene O.OE +00 2.6E.Q1 3.4E.()6 O.OE +00 O.OE + 00 4.0E.OJ 4.5E~ 2.0E~
3,3' -Dichlorobenzldine 5.8E-G4 1.2E.OJ 6.7E-G4 2.8E-G4 '1.7E-oJ 3.4E.OJ 2.4E-oJ 4.7E-oJ
Aniline O.OE +00 O.OE +00 O.OE+OO O.OE+OO O.OE + 00 2.3E.OJ 2.1E+00 4.2E.Q3
Azobenzene O.OE + 00 1.2E.04 1.2E.04 3.1E~ 3.8E.04 3.8E.04 2.8E~ 5.3E~
Benzidine O.OE + 00 6.7E~ O.OE +00 6.1E.OJ O.OE +00 2.1E~2 1.3E.Q1 4.1 E.Q2
SOIL BENEATH LAGOONS
Methylene Chloride O.OE + 00 O.OE + 00 2.2E.Q6 O.OE +00 O.OE + 00 O.OE + 00 O.OE +00 O.OE + 00
Benzene O.OE+OO 8.8E~ O.OE + 00 O.OE+OO O.OE+OO O.OE + 00 O.OE+OO 2.3E~
3,3' -Dichlorobenzidine O.OE + 00 1.3E~ 7.7E.03 3.1 E.OJ 8.3E-oJ 3.6E~2 6.7E.Q2 4.8E.Q2
Aniline 2.5E.OJ 5.7E.Q2 O.OE + 00 O.OE + 00 O.OE+OO O.OE + 00 1.3E~ 5.7E.OJ
Azobenzene 8.5E-G4 7.5E.04 8.5E~ 2.5E-G4 O.OE + 00 2.9E.OJ 2.1 E-oJ 4. t E-oJ
Benzidine O.OE + 00 1.2E.Q1 6.8E.04 1.2E.OJ O.OE+OO O.OE + 00 7.2E-oJ 3.6E.OJ
BERMS ,
Methylene Chloride O.OE+OO NP NP 3.0E.Q2 NP 7.8E.05 NP O.OE + 00
Benzene O.OE+OO NP NP O.OE+OO NP 5.4E.04 NP 2.1E~
3,3'-Dichlorobenzidine 4.3E~ NP NP 4.5E.04 NP 2.9E.OJ NP 5.1 E-oJ
Aniline O.OE + 00 NP NP O.OE + 00 NP 1.6E-G4 NP 4.6E~
Azobenzene O.OE + 00 NP NP 6.9E~ NP 2.8E.04 NP 5.0E~
Benzidin6 O.OE + 00 NP NP 1.8E.04 NP 1.3E.OJ NP 3.94E-oJ
SOIL AROUND LAGOONS
Methylene Chloride O.OE + 00 O.OE + 00 O.OE + 00 O.OE +00 O.OE + 00 O.OE + 00 O.OE + 00 O.OE + 00
Benzene O.OE+oo O.OE+OO O.OE + 00 O.OE+OO O.OE +00 O.OE + 00 4.2E.Q1 O.OE + 00
3,3' -Dichlorobenzidine 1.4E~2 1.4E.Q2 8.4E-oJ 1.5E.Q2 2.4E.Q2 8.6E.04 3.6E.Q2 1.8E.Q 1
Aniline O.OE + 00 2.5E~ O.OE + 00 O.OE + 00 O.OE + 00 2.2E.OJ O.OE + 00 7.9E~
Azobenzene O.OE +00 6.9E.04 6.9E~ 1.2E.OJ 1.5E~ 8.5E.04 9.7E~ 1.3E.Q2
Benzidine O.OE + 00 1.8E.04 O.OE +00 O.OE + 00 O.OE+OO O.OE + 00 2.0E-oJ O.OE + 00
-------
Units: ppm
Compound
SOIL AND SLUDGE
Methylene Chloride
Benzene
3,3'.Dlchlorobenzldlne
Aniline
Azobenzene
Benzidine .
SlUDGE ONLY
Methylene Chloride
Benzene
3,3'.Dtchlorobenzldlne
Aniline
Azobenzene
Benzidine
SOIL BENEATH LAGOONS
Methylene Chloride
Benzene
3,3'.Dichlorobenzidine
Aniline
Azobenzene
Benzidine
BERMS
Methylene Chloride
Benzene
3.3'.Dlchlorobenzidine
Aniline
Azobenzene
Benzidine
SOIL AROUND LAGOONS
Methylene Chloride
Benzene
3,3'-Dichlorobenzidine
Aniline
Azobenzene
Benzidine
TABLE 6
SURFACE WATER CONCENTRATIONS OBTAINED FROM THE AT123D MODEL (PPM)
Bofors Site
Muskegon, Michigan
lagoon 1 ..' ~3
""'11. .~
" . "
, ~ :-
O.OE+oo 1_+00
O,OE+oo UEG
5.ee-oe 1.3E.
2,5E~ O.OE +00
8.5E.oe 7.5E.oe
O.DE+OO 1.OE.Q2
O.OE +00
O.DE +00
5.ee-oe
O.DE +00
O.DE +00
O.DE +00
O.OE +00
O.OE + 00
O.DE+OO
2.5E-05
8.5E.oe
O.DE +00
O.DE +00
O.DE +00
4.3E~1
O.DE +00
O.DE +00
O.DE+OO
O.OE +00
O.DE+OO
1.4E~
D.Of +00
O.OE +00
D.DE + 00
O.OE+oo
2.6EG
1.2E.
O.DE + 00
1.2E.06
6.1E~
O.DE + 00
8.8E-D1
1.3E~
5.1E~
1.5E.06
1.2E~
NP
NP
NP
NP
NP
NP
O.DE +00
O.DE +00
1.4E-D4
2.5E.06
6.9E.06
1.8E.06
NP = Berms not present in these source areas.
Lagoon 5
3.1E.oa
3.4E.oa
1.1E-D4
O.DE +00
8.se.oe
1.1E-05
1,5E.oa
3.4E.oe
8.7E.oe
O.DE +00
1.2E.06
O.DE +00
2.2E.oa
D.DE+OO
1.1E-05
D.DE + 00
8.5E.06
6.8E.06
NP
NP
NP
NP
NP
NP
D.DE + 00
D.DE + 00
8.4E-05
D.DE + 00
6.9E.06
D.DE + 00
Lagoon 6
2.3E.06
D.DE +00
2.2E-05
D.DE +00
1.8E.oe
1.6E~
2.3E.06
D.DE +00
2.8E.oe
D.OE +00
3.1E~7
6.1 E-05
O.OE+OO
O.OE+OO
3. 1 E-05
D.OE+OO
2.5E.06
1.2E-05
,
3.0E-D4
D.DE +00
4.5E.06
D.OE+OO
6.9E~1
1.8E~
D.OE+OO
O.OE+OO
1.5E-D4
D.OE + 00
1.2E-05
D.OE + 00
Lagoon 1
5.1 E.oa
O.OE+OO
8.3E-05
O.Of +00
3.8E.o&
D.Of +00
5. 1 E.oa
D.Of +00
1-.1E.05
O.DE+OO
3.8E.o&
D.DE +00
D.DE+OO
D.DE+OO
8.3E-05
O.DE +00
D.DE +00
O.OE+OO
NP
NP
NP
NP
NP
NP
D.DE + 00
D.OE + 00
2.4E-D4
D.DE+OO
1.5E.06
D.OE+OO
lagoon 8
1.9E-05
4.DE-05
2.6E~
D.DE + 00
2.2E-05
D.DE +00
1.9E-05
4.DE-05
3.4E.05
2.3E.05
3.8E.06
2.1E~
D.DE+OO
D.DE + 00
3.6E-D4
D.DE +00
2.9E.05
D.DE +00
1.8E-Dl
5.4E.06
2.9E.05
1.6E.()6
2.8E.()6
1.3E~
D.DE+OO
D.DE +00
8.6E.()6
2.2E-05
8.5E-D6
D.DE +00
Lagoon 9
D.DE + 00
4.5E.06
1.0E.02
2.1E.02
1.6E-05
1.3E~
D.DE + 00
4.5E-D6
2.4E.05
2.1E-D2
2.8E-D6
1.3E~
D.DE+OO
D.DE -i 00
6.1E-D4
1.3E-D4
2.1 E-05
1.2E.05
NP
NP
NP
NP
NP
NP
D.DE + 00
4.2E~
3.6E-D4
D.DE+OO
9.7E-D6
2.DE.05
Lagoon 10
O.DE + 00
3.4E.oa
3.5E-D4
1.3E-D4
2.9E-05
3.9E-D4
D.DE + 00
2.DE-D1
4.1E.05
4.2E.05
5.3E-D6
4.1 E-D4
D.DE +00
2.3E-D1
4.8E-D4
5.7E.05
4.1E.05
3.6E.05
D.DE + 00
2.1E-D7
5.1 E.05
4.6E-D6
5.0E.06
3.94E~
D.OE +00
D.OE + 00
1.8E~
1.9E-D6
1.3E-D4
-------
The main health effects of these six compounds are as follows:
o
Aniline: Attacks the blood, liver, kidneys, and cardiovascu-
lar system. May cause anoxemia, central nervous system
depression, or cyanosis. Headaches, irritability, dyspnea,
unconsciousness, and even death may result from cyanosis.
Aniline is considered a potential human carcinogen.
o
Azobenzene: Can irritate the eyes, skin, and respiratory
tract. Azobenzene may also cause blood disorders. Azoben-
zene is considered a potential human carcinogen.
o
Benzene: Acute exposures produce primarily central nervous
system effects such as dizziness, nausea, headaches, loss of
balance, narcosis, coma, and death. Benzene is also a known
human carcinogen and causes several forms of leukemia.
o
Benzidine: Direct contact may cause contact dermatitis and
primary irritation or sensitization. Benzidine is also a
known urinary tract carcinogen with an average latency period
of 16 years.
3.3'-Dichlorobenzidine (DCB): Direct contact may cause
allergic skin reactions. DeB may contribut~ to bladder
cancer and is considered a potential carcinogen.
o
o
Methvlene Chloride: Repeated contact may cause dermatitis
and eye and upper respiratory irritation. Methylene chloride
is also a mild narcotic; effects incaude: headache, giddi-
ness, stupor, irritability, and numbness. Exposure may cause
elevated carboxyhemoglobin levels. Methylene chloride is
considered a potential human carcinogen.
Excosure Assessment
Based on the baseline risk assessment, several exposure pathways
were evaluated, including:
o
ai~.s a result of volatilization of organic compounds from
tb4r_8Urface of the lagoons;
wetland sediments through resolubilization of contaminants
and transport downstream in Big Black Creek;
groundwater through direct use of the groundwater,
surface water, through potential contamination of Big Black
Creek by contaminated groundwater;
direct contact with waste, and
ingestion of waste.
o
o
o
o
o
-------
Three of these pathways presented the most significant risks to
potentially exposed populations:
o
ingestion of contaminated groundwater from infiltration of
contaminated precipitation from the lagoon area:
ingestion of contaminated surface water:
inhalation of contaminated air from volatilization of organic
compounds from the lagoon area surface.
o
o
Potentially exposed populations used in the baseline risk assess-
ment included adults living on- and off-site. Groundwater, air,
and unsaturated-zone transport modeling was performed for the
compounds of concern to characterize exposure point concentra-
tions. Modeling procedures were developed to evaluate receptor
exposure to the chemicals of concern for the lagoon sludge,
berms, soil beneath the sludge, and soil around the lagoons for
each lagoon area. The emission rates into the air or water from
the sludge, soils and berms were first calculated, then the
transport through the air and groundwater was evaluated.
A computer program was developed to calculate volatile air
emission rates from each lagoon source area. A 70-year average
emission rate was determined for each source area. Air risks
were determined from the downwind concentrations at receptor
locations.
Risks from dust emissions were estimated for exposure by inhala-
tion. These risks were estimated as approximately 100 times less
than the risks from inhalation of volatile emissions. Risks from
inhalation of metals within the dust are expected to be less than
risks from inhalation of organic compounds adsorbed to dust
particles, because metals have higher settling velocities and are
not transported as easily.
Chemical emissions from the unsaturated zone to the groundwater
were also estimated. Simulations were run for each lagoon source
area to determine the contaminant mass input to the groundwater
from the sludge and soil beneath the lagoons, the sludge only,
the~o'" beneath the lagoons only, the berms, and the soils
aro - . .' lagoons. The 70-year average mass inputs were then
calcul~ "and the results were used as input to a groundwater
model~' The~ groundwater risks were then calculated using the
maximua groundwater concentrations determined with the ground-
water model.
Surface water risks were evaluated using average contaminant
concentrations in groundwater expected to enter Big Black Creek,
accounting for dilution by clean upstream water and groundwater
on the opposite side of Big Black Creek. The dilution rate was
estimated to be approximately 100, therefore, the surface water
concentrations are 100 times lower than the corresponding groun~
water concentration.
-------
The major assumptions used in these models were:
o
The contamination is uniformly distributed within the soil or
sludge matrix. .
The contaminant of interest is assumed to be bound to either
the soil or the sludge.
The waste does not flow within
The adsorption isotherm of the
linear within the depth of the
time.
No flow of gas is induced within the waste matrix.
The diffusion coefficient does not vary with either concen-
tration or time.
The concentration of the constituent of interest in the gas
phase at the surface of the lagoon is much lower than the
concentration of the constituent of interest in the gas phase
within the waste matrix.
No diffusion of the contaminant into depths below the waste
layer is assumed.
contaminant vapor, waste, solid, and water equilibrium is
established at all times within the waste matrix.
Hydrolysis, biodegradation, and ligand formation were assumed
to be insignificant mechanisms at this site.
The aquifer is infinitely wide.
o
o
o
the carrier matrix.
constituent of interest is
waste and does not change with
o
o
o
o
o
o
o
The assumptions made for the risk assessment include:
o
People would be exposed to areas where the highest levels of
contamination were found, i.e., maxtmum concentrations were
used during the risk assessment to generate risks.
o
70-kg adult resident is exposed daily over a 70-year
lifetime.
o
Daily intake is 2 liters per day of groundwater or surface
water and 20 cubic meters per day of air.
100 percent absorption is assumed.
~~9roundwater pumping and treatment system is turned off.
o
o
These conservative assumptions allow the risk assessment to
emphasize health protection.
Toxicitv Assessment
All of the six compounds of concern are known or potential human
carcinogens. Cancer potency factors (CPFs) have been developed
by U.S. EPA's Carcinogenic Assessment Group for estimating excess
lifetime cancer risks associated with exposure to potentially
carcinogeni21chemicals. CPFs, which are expressed in units of
(mg/kg-day) , are multiplied by the estimated intake of a poten-
-------
tial carcinogen, in mg/kg-day, to provide an upper-bound estimate
of the excess lifetime cancer risk associated with exposure at
that intake level. The term "upper bound" reflects the conserva-
tive estimate of the risks calculated from the CPF. Use of this
approach makes underestimation of the actual cancer risk highly
unlikely. Cancer potency factors are derived from the results of
human epidemiological studies or chronic animal bioassays to
which animal-to-human extrapolation and uncertainty factors have
been applied. The cancer potency factors for these compounds are
presented in Table 7. RFDs were not used because the carcino-
genic toxic effects of the compounds of concern far exceeded the
non-carcinogenic toxic effects.
This table also presents information on whether the compound is a
known or potential carcinogen. As shown in the table, benzene
and benzidine are known human carcinogens (A); the other com-
pounds of concern are potential human carcinogens (B2). Benzi-
dine is the most carcinogenic compound and DCB is the second most
carcinogenic compound of the compounds of concern. Benzidine and
DCB are several orders of magnitude more carcinogenic than the
other compounds. These two compounds, and particularly benzi-
dine, therefore, provide the highest risks at the site and drive
the level of remediation required.
RISK CHARACTERIZATION
Excess lifetime cancer risks are determined by multiplying the
intake level with the cancer potency factor. These risks are
probabilities_Ghat are generally expres$ed in scientific no~gtion
(e.g., 1 x 10 ). An excess lifetime cancer risk of 1 x 10
indicates that, as a plausible upper bound, an individual has a
one in one million chance of developing cancer as a result of
site-related exposure to a carcinogen over a 70-year lifetime
under the specific exposure conditions at a site. Only potential
future land use was evaluated since there is no current land use.
Potential Future Conditions - Residential EXDosure Scenario
As d=-". ..d previously, the site was divided into eight source
area '<.,~ir subareas. The carcinogenic risks were developed
for e . Att the contaminants of concern for each of these
subar""'.f.or each of the three exposure pathways. A discussion
of the risks. associated with the future. use- residential exposure
scenario tor each of these pathways are presented below.
Air Inhalation Risks
Air inhalation risks are
table, these risks range
lagoon sludge posing the
lowest risks.
presented in !~ble 8. As sh~wn in the
from 1.2 x 10 to 7.9 x 10 , with the
highest risks and berms posing the
-------
TABLE 7
COMPOUNDS OF CONCERN AND CARCINOGENICITY
Bofors Site
Muskegon, Michigan
Compound Potency Slope (mQ/kQ/day) EPA Classification
Aniline 0.0057 B2
Azobenzene 0.17 B2
Benzene 0.029 A
Benzic:llne 230.0 A
3.3'-Oichloro~nzidlne (DCS) 3.5 B2
Methylene Chloride 0.0075 B2
A:
Known human carcinogen.
Sa:
Known animal carcinogen; Probable human carcinogen ~rom Risk Assessment Guidance for Superfund, 1989)
;'
-------
TABLE 8
AIR RISKS
Bofors Site
Muskegon, Michigan
(AzImuth '" 0)
Receptor: r = 402.34
Azimuth - 0
I~ t
Compound ~ Lagoon 3 Lagoon 5 Lagoon 6 Lagoon 7 Lagoon 8 Lagoon 9 Lagoon 10
SLUDGE ONLY
Methylene Chloride NO NO 1.5E.Q8 1.5E~7 4.9E.Q8 5.1E~7 NO NO
Benzene NO 8.2E.
-------
Groundwater Inqestion Risks
Groundwater ingestion ris~f are present~g in Table 9. These
risks range from 9.9 x 10 to 3.11x 10 . Overall, the sludge
presents a total risk of 9.9_~ 10 , the soil beneath the lagoons
has a total risk of 6.6 x 10 , aD2 the soil around the lagoons
presents a total_~isk of 1.7 x 10 and the berms present a total
risk of 1.2 x 10 . The sludge and soil beneath the sludge pose
the greatest overall risk for groundwater ingestion. Total
groundwater ingestion risks resulting from sludge, soil beneath
lagoons, soil around lagoons, or berms are all above acceptable
limits. The highest magnitude of risk is associated with
benzidine. DCB poses the next highest risk.
Surface Water Inqestion Risks
Surface water ingestion risks are presented in Table 10. These
risks assume that the groundw~ter pumping and treatIDint system is
turned of;. The calculated r~sks range from 1 x 10 to
3.4 x 10-. Benzidine is the chemical which drives the overall
risk for surface water~2 Benzidine's combined risk for all source
areas exceeds 2.5 x 10 . Thus, even though the surface water
poses risks substantially lower than the groundwater, the risks
from surface water ingestion are above the acceptable range by at
least four orders of magnitude.
Combined Risks
The highest excess cancer risks developed were associated with
the groundwater exposure pathway. The combined carcinogenic
risks reflecting all the contaminants of concern and all_rxposure
pathways of concern are estimated to be approximately 10 excess
cancer risk. Non-carcinogenic effects are estimated to be
insignificant in this operable unit, since the metals in the
sludges and soils do not appear to exhibit significant mobility.
If mobile, the non-carcinogenic effects would become significant.
Therefore, non-carcinogenic effects were not used to estimate the
level of remediation required.
~. '"" \ -
.".' ~.
Risks and risk-based cleanup criteria should be considered
approximations due to the limitations and uncertainties of the
manner in which these concentrations are computed. When modeling
contaminant transport, when estimation was necessary, a value was
chosen to provide the most conservative realistic risk estimate.
Tests with the model have shown that contaminant concentrations
within the soil and sludge have the greatest effect on overall
risks. Other parameters, such as permeability, organic carbon
content, surface area, and volumes may have significant effects
on calculated risks.
-------
TABLE 9
EXCESS CANCER RISKS FROM GROUNDWATER INGESTION
Bofors Site
Muskegon, Michigan
Compound Lagoon t Lagoon 3 Lagoon 5 Lagoon 6 Lagoon 7 Lagoon 8 Lagoon 9 lagoon 10
SOIL AND SLUDGE
Methylene Chloride NO \: NO 1.6E-09 4.9E~ 1.1E-09 4.1E-07 ND ND
Benzene NO I t;. 5.2E-04 2.9E-09 ND ND 3.4E-06 3.8E-07 2.9E-09
3,3-Dichlorobenzldine ue.GJ r\' 8.4E-04 1.1E-03 2.2E-04 8.4E-04 2.6E-03 1.0E-01 3.5E-03
Aniline 4. 1 E-07 NO NO ND NO ND 3.4E-04 2.1 E-06
Azobenzene 2.~ 2.4E-06 2.7E-06 5.7E-07 1.2E-06 6.9E-06 5.0E-06 9.4E-06
Benzidine tIL- 1.0E+oo 7.2E-03 1.0E-01 ND ND ~ ~
Total 8.2E.Q5 1.0E+oo 8.3E-03 1.0E-01 i4e.04 2.6E-03 6.7E-01 2.3E-01
SLUDGE ONLY
Methylene Chloride NO NO 7.0E-10 4.9E-06 1.1E-09 4. 1 E-07 ND ND
Benzene NO 2.2E-04 2.9E-09 ND NO 3.4E-06 3.8E-07 1.7E-08
3,3-Dichlolobenzldine 5.9E.Q5 1.2E-04 8.8E-05 2.8E.Q5 1.7E-04 3.4E-04 2.4E-04 4.8E-04
Aniline NO NO ND ND ND 3.8E-07 3.4E-04 6.9E-07
Azobenzene NO 3.8E-07 3.8E-07 1.0E-07 1.2E-06 1.2E-06 8.9E-07 1.7E-06
Benzidine ND 3.6E-01 !m..- 4.0E-02 ND 1.3E-01 5.9E-01 2.4E-01
Total ~ 3.6E-01 6.8E.Q5 4.0E-02 illi)i 1.3E-01 5.9E-01 2.4E-01
SOil BENEATH LAGOONS
Methylene Chloride NO NO 9.0E-10 ND ND ND ND ND
Benzene ND 7.4E-08 ND ND ND ND ND 1.9E-08
3,3-Dichlorobenzidine NO 1.3E-03 7.8E-04 3.1 E-04 8.4E-04 3.6E-03 6.8E-03 4.9E-OJ
Aniline 4.1 E-07 9.5E-06 ND ND ND ND 2.2E-06 9.4E-07
Azobenzene 2.7E-06 2.4E-06 2.7E-06 8.0E-07 ND 9.4E-06 6.6E-06 1.3E-OS
Benzidine NO ~ ~ lli:m !m..- !m..- 4.7E-02 2.4E-02
Total 3. 1 E-06 5.4E-01 5.3E-03 8.4E-03 8.4E-04 3.6E-03 5.4E-02 2.9E-02
BERMS
Methylene Chloride ND NP NP , 6.6E.Q6 NP 3.3E~ NP ND
Benzene NO NP NP NO NP 4.7E-07 NP 1.8E-08
3,3-Dichlorobenzldine 4.4E-o& NP NP 4.6E.Q5 NP 2.9E-04 NP 5.2E-04
Aniline ND NP NP ND NP 2.6E~ NP 7.5E-08
Azobenzene ND NP NP 2.2E-07 NP 8.9E-07 NP 1.6E-06
Benzidine ~ NP NP 1.2E-02 NP 8.6E-03 NP 2.5E'{)2
Total 4.4E-o& NP NP 1.2E-02 NP 8.9E-03 NP 2.5E'{)2
SOil AROUND LAGOONS
Methylene Chloride NO NO ND ND ND ND ND ND
Benzene NO NO ND ND ND ND 3.5E-04 ND
3.3-Dichlorobenzidine 1.4E..()3 1.4E-03 8.5E-04 1.5E-03 2.4E-03 8.7E-05 3.6E-03 1.8E'{)2
Aniline ND 4.1E-08 ND ND ND 3.6E.{)7 ND 1.3E'{)7
Azobenzene ND 2.2E-06 2.2E-06 3.9E-06 4.9E-07 2.7E-06 3.1 E-06 4.3E-OS
Benzidine !':!!L- 1.2E-03 till.- till..- till..- till..- 1.3E'{)2 till.-
Total 1.4E..()3 2.6E-03 8.5E-04 1.5E-03 2.4E-03 9.0E'{)5 1.7E'{)2 1.8E'{)2
NO: Contaminant not detected in sample(s) from that lagoon.
-------
TABLE 10
EXCESS CANCER RISKS FROM SURFACE WATER INGESTION
Bofors Site
Musekgon, Michigan
Compound Lagoon 1 Lagoon 3 Lagoon 15 Lagoon 6 lagoon 7 Lagoon 8 Lagoon 9 lagoon 10
SOIL ANO SLUDGE
Methylene Chloride NO .~ ~ NO 3.0E-10 4.9E-10 1.1E-11 4.1E.oJ NO NO
Benzene. NO ... 5.2E.()6 2.9E-11 NO NO 3.4E.()8 3.8E.oo 2.9E-11
3,3-Dichlorobenzldlne U6G7 ~. 9.4E.()6 1.1E~ 2.2E.()8 8.4E.()8 2.6E.()5 1.0E.03
! 3.5E.()5
Aniline 4. tE-G8 NO NO NO NO NO 3.4E.()6 2.1 E.Q8
Azobenzene 2.~ 2.4E.()6 2.7E~ 5.7E.oJ 1.2E.Q8 6.9E.Q8 5.0E.Q8 9.4E.()8
Benzidine NO 1.0E-42 7.2E.05 1.0E.03 ~ mL- 5.7E.03 2.3E.03
T ot81 i.2Ei7 1.iie.Q2 8.3E~ 1.0E.03 8.4E.()6 2.6E.()5 6.7E.03 2.3E.03
SLUDGE ONLY
Methylene Chloride NO NO 1.0E-10 4.9E-10 1.1E-11 4. 1 E.oJ NO NO
Benzene NO 2.2E.()6 2.9E-11 NO NO 3.4E.()8 3.8E.oo 1.7E.10
3.3-Dichlorobenzldine 5.9E~7 1.2E.()6 6.8E~7 2.8E~7 1.7E«i 3.4E«i 2.4E.()6 4.8E«i
Aniline NO NO NO NO NO 3.8E.oJ 3.4E«i 6.9E.oo
Azobenzene NO 3.8E.09 3.8E.oo 1.0E.oo 1.2E.()8 1.2E.Q8 8.9E.oo 1.7E-08
Benzidine NO 3.6E.03 ~ 4.0E~ ~ 1.3E.03 5.9E.03 2.4E.03
T otat 5.9E~7 3.6E.03 6.8E~7 ~ 1.7E«i 1.3E.03 5.9E.03 2.4E.03
SOIL BENEATH LAGOONS
Methylene Chloride ND NO 2.0E-10 NO NO ND ND NO
Benzene NO 7.4E-10 ND NO ND ND ND 1.9E-10
3.3-Dichlorobenzidine ND 1.3E.()5 7.8E.()6 3.1 E«i 8.4E«i 3.6E.()5 6.8E.()5 4.9E-05
Aniline 4. 1 E.oo 9.5E.()6 ND NO ND ND 2.2E-08 9.4E~
Azobenzene 2.7E.Q8 2.4E.()6 2.7E.Q8 8.0E~ NO 9.4E-08 6.6E-08 1.3E~7
Benzidine ND 5.4E-03 4.5E.()5 8. 1 E-05 ND mL- 4.7E-&I 2.4E-04
Total 3.iE-Oi 5.4E-03 5.3E.05 8.4E-05 8.4E«i 3.6E-05 5.4E-&I 2.9E-04
BERMS
Methylene Chloride ND NP NP ' 6.6E-08 NP 3.3E-10 NP . NO
Benzene ND NP NP NO NP 4.7E.oJ NP 1.8E-10
3.3-Dichlorobenzidine 4.4E.Q8 NP NP 4.6E~7 NP 2.9E«i NP 5.2E-06
Aniline NO NP NP NO NP 2.6E-10 NP 7.0E-10
Azobenzene ND NP NP 2.2E~ NP 8.9E~ NP 1.6E-08
Benzidine ~ NP NP 1.2E-04 NP 8.6E.()5 NP 2.4E-03
Total 4.4E.Q8 NP NP 1.2E-04 NP 8.9E-05 NP 2.4E-03
SOIL AROUND LAGOONS
Methylene Chloride ND NO ND NO NO ND NO NO
Benzene NO NO NO NO NO ND 3.5E.()6 NO
3.3-Dichlorobenzidine 1.4E-05 1.4E.05 8.5E-06 1.5E-05 2.4E-05 8.7E-07 3.6E-05 1 8E-04
Aniline ND 4.1E-10 NO NO NO 3.6E~ NO 1.3E-09
Azobenzene ND 2.2E~ 2.2E-08 3.9E-08 4.9E~ 2.7E-08 3. 1 E-08 4.3E-07
Benzidine ~ 1.2E.05 ~ NO NO ND 1.3E-&I !:ill-
Total 1.4E-05 2.6E.05 8.5E-06 15E-05 2.4E-05 9.0E-07 1.7E-04 1.8E-04
NO: Contaminant not detected in sample(s) from that lagoon.
-------
Environmental Risks
Based on the preliminary evaluation performed for the preliminary
risk assessment, site contamination does not appear to have
affected critical habitats or endangered species. The State
completed a qualitative evaluation of the likelihood and magni-
tude of each identified exposure pathway on endangered species.
No adverse affects on wildlife were identified in this prelimi-
nary assessment.
The wetlands on this site are located in the floodplain on both
sides of Big Black Creek. A portion of these wetlands are
located within the L.O.U., as shown in Figure 2. These wetlands
consist of a variety of plant communities with good species
diversity. The entire valley area is composed of a complex
mosaic of different wetlands, ranging from forested wetlands to
small ponds. There are mature communities as well as recently
developed wetlands, and wetland formation is still occurring
within this active floodplain area. These wetlands appear to be
relatively undisturbed by site contamination. However, U.S. EPA
believes that, if the extraction system were turned off, impact
to wetlands might occur from discharge of contaminated
groundwater.
Although an animal study was not conducted on the site, past
experience indicates that these types of wetlands would support
good populations of various animal species. The relatively
isolated and undisturbed nature of these wetlands, their
proximity to upland woods, and the cont~uous band they form
along Big Black Creek indicate potential for supporting good
populations of deer, fur bearers, songbirds, migratory water
fowl, herons, egrets, reptiles, amphibians, and a variety of
invertebrates. Most likely, this wetland band also serves as a
pathway for local movement of animals.
None of the wetland types or species encountered on the project
site are unique or rare in the Upper Midwest. It is possible,
however, that individual plant or animal species occurring in
these wetlands may be federally protected or state protected
speci~:.<-~,
SU_-r:y
Actual or threatened releases of hazardous substances from this
site, if not addressed by implementing the response action
selected in this ROD, may present an imminent and substantial
endangerment to public health, welfare, or the environment.
-------
FEASIBILITY STUDY ISSUES
Remedial Action Obiectives
To evaluate the effectiveness of the technologies assessed in the
treatability study, the groundwater ingestion risks were used to
estimate the post-treatment chemical concentrations necessary to
meet specified risk levels. As described previously, the ground-
water ingestion route of exposure poses the greatest risks to
human health and the environment.
The cleanup crit~iia developed are presented in Tables 11 (10-6
Risk) and 12 (10 Risk). These are the concentrations to which
the sludge, berms, or soil must be treated to achieve the
indicated risk level. In these tables, when the u.s. EPA
Contract Laboratory Program (CLP) contract-required quantitation
limit (CRQL) for the compound is higher than the risk-based
cleanup criterion, the CRQL is used as the cleanup criterion.
Each chemical and subarea where the cleanup concentration
exceeded the concentration found in the original samples is
designated by NA (not appropriate). These areas do not exceed
the specified risk level and do not require treatment.
The distribution of the contaminants within each subarea was used
in conjunction with the risk-based cleanup criteria to determine
the technology combinations presented in the following alterna-
tives.
The mass of each contaminant in each lagoon subarea was calcu-
lated from the RI data and the distribution of each compound in
each of the four types of subareas were calculated, as presented
in Table 13. As shown in this table, the sludge and berms
account for 64 percent of the contamination by the compounds of
concern. The soils under and around the sludge account for
36 percent of the contamination by the compounds of concern.
Benzidine drives the remediation because of its extremely high
toxicity. Of the total benzidine distribution at the site,
83 percent is present in the sludges and berms. These figures
clearly indicate that the majority of the contamination is
pres.n~~inthe sludges and berms and that the soils beneath and
around'the sludge are significantly less contaminated than the
sludq..: and berms.
ADDlicable or Relevant and Aoorooriate Reauirements
section 121(d) of SARA mandates that, for all remedial actions
conducted under the CERCLA, cleanup activities must be conducted
in a manner that complies with applicable or relevant and
appropriate requirements (ARARs). The NCP and SARA have defined
both applicable requirements and relevant and appropriate
requirements a~ follows:
-------
UnIIa; ppb TABlE 11
SOURCE 0CNTR0t. Q..EANUP CATEAIA TO ACHIEVE 10" FISI<8
801.... SIIe
.........., UicIIIg8n
OACJUONATER INOESTION
Compound LIgaan 1 l.8goon 3 l.8goon II Lagoon II
8l 88 " ".- 8 8l 88 8l& sa SA 8 Sl se Bl&se SA 8 8l 88 Bl&se SA 8
'
Melhyl8ne ChlorIde NO NO ... '1 "- NJ NO NO NO NO -- NA NA NA NO - NA NO NA NO 110
8enz- NO NO ND' ~. J NJ 4!100 NA 180 NO -- NA NO NA NO -- NO NO NO NO NO
3,3' -Olchlorobenzidine : NO "- :,. 3Il8OO R 3Il8OO 101 3Il8OO tal 3Il8OO IQI -- _:b:l3ll8OO tal 3Il8OO tal ~Jd 3Il8OO 101 3Il8OO PI 3Il8OO 101 ;.",'.:,'.:.'.:..:.". 3Il8OO R
AnIlIne NO NA .. 1M NJ NO 110 880 NA --- NO NO NO NO - NO NO NO NO NO
~ NO " ",, " NO NJ NA GOOOO 2,~lo" NA
: 40000 - aooo 24000 1100 - NA NA NA 1000101 NA
Benzidine NO NO NO NO NJ .:A: "':':"':p: ijijiCiG'Ja ~A: -- NO 1.iR) ~:Ar NO .:fj:t: IOiOQp, : '*~\ NO 1~:A}
-
OACJUONATER INOESTION
Compound I.8goan 7 l.8goon II l.8goon 1 lAgoon 10
81. 88 81.&88 SA 8 8l S8 8l& S8 SA 8 81. sa Sl&S8 SA B 8l 58 Sl&58 SA B
MeIhyI8ne ChlorIde NA NO NA NO -- INA NO NA NO II NO NO NO NO - NO NO NO NO NO
Benz- NO NO NO NO --- Ie20 NO 410 NO NA NA NO NA 825 IQI - NA NA NA NO NA
3,3' -OIchlofobenzldJne - ~iii' ,..~'.: ~iI: --- 3Il8OO 101 iiiliGiib 3Il8OO 101 1800 3Il8OO 101 48000 3Il8OO PI 3Il8OO PI 3Il8OO PI - 3Il8OO IQI 880 PI 880PI -tQI 3Il8OO (0)
AnIlIne NO NO NO NO --- NA NO NA NA NA 30000 IQI 4!500 2800 NO .- 2!500 NA 1200 NA NA
Azobenz- 18000 NO 3800 NA -- 28000 1000 PI 2100 '~ NA NA 11000 400000 1000 PI .- NA 3800 1!5000 1000 PI 1!5000
Benzidine NO NO NO NO ..-- ~:b NO 1~t'i NO ~~iI\ 1~iat? I~a 'Wiil' ~f.j ~Iii»:,~'::, ND 1~R
legend;
NA: No! applicable; cI88nup r;oncen,8IIon8 hI8fI8Ilh8n GOnC8I1IJ8IIona d888c:I8d In""'.
NO: Hal delec:18d In orIgIn8I umpIe.
Sl ; Sludge. ,
S8: SolI b8n8a1h 18gaon.
Sl& 58; Sludge 8nd aoII b8nNIh I8goon combIn8d.
SA: SolI ..ound 18goon.
B ; Berm.
EIl indicates 8xposure roule, compound, IIIId cI88nup 8I8nd8rd which drM r8m8dl8llon. b888d on rtab.
-------
UnlIt: ppb TABlE 12
SOURCE CX»IfROl ClEANUP CRTEAA TO ACHIEVE 10" RlSInI*1II8IlontI detected In sample.
NO: Nal d818Cled In 0IIg1n8I sample.
"
Sl: Sludge.
00: SolI ~ Iegoon.
Sl&oo: Sludge end 8011 bene8lh I8goon combin8d.
SA: SoIl 8Iound Iegoon.
B: Bean.
Cl 1nd1c8l.. ..posur. rouI8, compound, end clMnup ........ds which drive r.rn8dlalIon.
-------
TABLE 13
CONTAMINANT MASS DISTRIBUTION BY SUBAREA
Bofors Site
Muakegon, Michigan
Units: mgJkg (ppm) 'j.:,.
!i;'c .$:1 T olal Mass Percent Mass
\,f: -,'j t.--:: .
!:~ J' -': -~ ':;
SL sa B SA SL SB B SA
Methylene Chloride 43.0 0.1 3.7 92.0'110 0.2 8.0 0.0
Benzene 7782.3 2.0 10209.8 43.0'110 -0.0 0.0 57.0
DCB 2712333.0 24171.0 20905.0 253513.0 48.0'110 4.0 4.0 44.0
Aniline 38770.8 626.6 14.8 132.0 98.0'110 1.6 -0.0 0.3
Azobenzene 188478.8 18193.4 2264.8 4250.3 88.4'110 8.5 1.1 2.0
Benzidine 40654.5 81226 ---2Qa.2 121.1 ~ ~ Q.! .JU
Percent of Total Mass 61.5'110 5.7'110 2.6'110 30.1 'It
LEGEND:
SL: Sludge.
,
SB: SoU ........ath lagoon.
B: Berm.
-------
o
Applicable Requirements are those federal and state require-
ments that would be legally applicable, either directly or as
incorporated by a federally authorized state program, if the
response action was not undertaken pursuant to Section 104
or 106 under CERCLA.
o
Relevant and Appropriate Requirements are those federal and
state requirements that, while not legally "applicable", are
designed to apply to problems sufficiently similar to those
encountered at CERCLA sites that their application is appro-
priate. Requirements may be relevant and appropriate if they
would otherwise be "applicable" but for jurisdictional
restrictions associated with the requirement.
other Requirements to be Considered are federal and state
non-regulatory requirements, such as guidance documents or
criteria. Advisories or guidance documents do not have the
status of potential ARARs. However, where there are no
specific ARARs for a chemical or situation, or where such
ARARs are not sufficient to be protective, guidance or
advisories should be identified and used to ensure that a
remedy is protective.
o
The pertinent ARARs are' summarized in the des~ription of each
alternative and addressed in detail in the section on Comparative
Analysis of Alternatives.
Resource Conservation and Recoverv Act Issues
;
The applicability of the Resource Conservation and Recovery Act
(RCRA) hazardous waste regulations to the treatment, storage, and
disposal of contaminated sludge, soil, and berms at this site was
reviewed. Several sludge/soil samples were tested for ignitabil-
ity, corrosivity, reactivity, and toxicity to determine their
classification as a RCRA characteristic hazardous waste. Only
one sludge sample showed a RCRA hazardous characteristic
(reactivity). All the samples tested for the other characteris-
tics, including TCLP, showed negative results. Since only one
samp~~,,~~ted positive as a RCRA characteristic hazardous waste,
and ortly for one characteristic, it is not expected that the
waste at this site is a RCRA characteristic hazardous waste.
Howev.r~ this should be confirmed during the design. If the
waste is a RCRA characteristic waste, then treatment and disposal.
must comply with RCRA requirements.
-------
After treatment, the resulting ash may exhibit the characteristic
of toxicity through TCLP testing for metals, because the metals
may be concentrated in the ash and their mobility increased.
This should also be confirmed during the design phase.
RCRA U-listed hazardous wastes are discarded commercial chemical
products, off-specification species, container residues, and
spill residues that contain substances listed in 40 CFR
261.33(f). While the sludge and berms contain constituents
included in the list of U wastes contained in 40 CFR 261.33(f),
it is unlikely that the contaminated media in the L.O.U. were
discarded commercial products, off-specification species,
container residues, and spill residues. Rather, the sludge in
the L.O.U. is production waste from the manufacture of DCB and
benzidine.
Treatabilitv Studies
Treatability testing has been performed to evaluate treatment of
the groundwater. Ozone oxidation, UV/peroxide oxidation, and
carbon adsorption were evaluated at the bench-scale. This
testing indicated that ozone oxidation offers the best combina-
tion of cost-effectiveness and performance of the technologies
tested at this site.
Treatability testing has also been performed to evaluate treat-
ment of the sludges and soils in this operable unit. Soil
washing, low temperature thermal desorpbion, and solidification/
stabilization technologies were evaluated at the bench-scale.
These tests indicated that soil washing has limited applicability
to this site, that LTTD may be suitable as a remedial technology
at this site, and that stabilization is not suitable for use at
this site. .
o
o
DESCRIPTION OF ALTERNATIVES
The remedial alternatives considered for this operable unit are:
,-.'
Ai~ative 1: No Action.
A~t8r.native 2: Capping: Institutional Controls on Ground-
wa~8r U.. and Site Access: Pump and Treat Groundwater
Perpetually.
Alternative 3: On-Site Incineration/Low-Temperature Thermal
Desorption: Capping: Pump and Treat Groundwater for a Finite
Period.
Alternative 4: On-Site Incineration/Low-Temperature Thermal
Desorption: On-Site Landfilling: Pump and Treat Groundwater
for a Finite Period.
o
o
All the remedial alternatives contain the same following
components:
-------
o
Maintaining a fence around the site. The existing fence
would be maintained around the site to prevent trespassing on
the site. The fence includes signs warning potential tres-
passers about contamination and threats to human health and
the environment at the site.
Monitoring groundwater and surface water. Samples from
existing monitoring wells would be collected to assess the
effectiveness of the remedial action, if applicable. Samples
would be collected four times during the first year of
monitoring and twice annually in subsequent years. To
monitor surface water quality, samples from two locations
would be collected in Big Black Creek. The surface water
samples would be collected on four occasions during the first
year of monitoring and twice annually in subsequent years.
o
Remedial Alternatives 2, 3, and 4 contain the following addi-
tional components:
o
Constructing on-site roads. About 4,500 feet of roads would
be constructed on the site, primarily near the sludge
lagoons, to accommodate truck traffic on the site during the
remedial action cleanup.
o
Monitoring air. Air samples would be collected from the work
zone and perimeter of this site during excavation of the
contaminated material. Air samples would also be collected
to measure the potential emissions from the treatment facili-
ties. These samples would be collected from the facility
stack and from the site perimeter. The frequency of sampling
would be determined prior to construction.
o
Groundwater pumping and treatment. The groundwater is
currently being pumped using the existing groundwater extrac-
tion system. For this remediation, the pumping system would
be upgraded and the distribution system would be relocated to
accommodate excavation and treatment of the lagoons. A new
treatment system would be built. Treatability studies
indicated that ozone treatment will achieve effluent concen-
t~lons below detection limits. Therefore, the groundwater
would be treated using an ozone oxidation treatment system or
a system that achieves equivalent performance. The treated
effluent would then be discharged to Big Black Creek.
Although a National pollutant Discharge Elimination System
(NPDES) permit is not required because treatment and dis-
charge of the effluent occurs on-site, the substantive
requirements of the permit will be met. The proposed Best
Available Technology (BAT) discharge standards for the
indicator chemicals are as follows: Methylene Chloride, 5.0
ug/l: Benzene, 5.0 ug/l: DCB, .06 ug/l: Aniline, 4.0 ug/l:
Benzidine, .04 ug/l: discharge standards for Azobenzene are
in the process of being developed. The groundwater treatment
-------
system will be operated to achieve these standards.
Alternative 1:
No Action
The no action alternative involves leaving the L.O.U. contaminant
source areas intact and terminating operation of the existing
groundwater pumping and treatment system which currently controls
groundwater migration off-site. Groundwater and surface water
monitoring will be performed semiannually to evaluate impacts of
terminating operations of the groundwater pumping and treatment
system. Therefore, the potential for release of contamination to
air, groundwater, and surface water pathways and for exposure to
compounds above acceptable risk levels will continue to exist.
This alternative will not meet target risk levels and no reduc-
tion of toxicity, mobility or volume of site contaminants ~ill
occur. Risk levels predicted £~r this alternative are 10- for
the air inhalat!2n pathway, 10 for the groundwater ingestion
pathway, and 10 -lfor the surface water ingestion pathway, for a
total risk of 10 . This alternative is included as a NCP
requirement and also to provide a baseline against which other
alternatives may be compared.
Alternative 2: CaD. Institutional Controls. FumD and Treat
Groundwater PerDetuall y .
The components of this alternative are presented in Figure 3.
The components presented in this figure are approximate and may
be modified during design or construction.
Treatment ComDonents
;
There is no treatment of the sludges and soils in this alterna-
tive. Fluids generated from sludge compaction during the
construction of the cap will be treated in the groundwater treat-
ment system. This is estimated to be 3.1 million gallons over a
two-year period. The groundwater will be pumped and treated
perpetually using an ozone oxidation or equivalent treatment
system. Treatment levels will be determined in the next operable
unit.
~~~:~...;,'.~
.. .
Con~ainment ComDonents
All eiqht laqoon source areas (Lagoon Areas 1,3,5,6,7,8,9,10)
will be capped (approximately 23 acres of contaminated sludges
and soils). The cap, designed to meet the intent of RCRA Sub-
title C, and constructed to meet U.S. EPA guidance provided in
40 CFR 264.310, will consist of an upper 2-foot vegetated soil
layer underlain by filter fabric and a 12-inch sand layer over a
low permeability layer. The low-permeability layer will be
composed of a synthetic liner (minimum thickness of 20 mil) over
a 2-foot compacted clay layer (i.e., soil liner) with a permea-
bility less than or equal to 1 x 10-7 em/sec. .
-------
~~.
$
!
Figure 3
Components of Alternative 2
All Source Areas; Capping with
23 Acres 01
Contaminated RCRA Subtitle C -
Sludge & Soil Cap
. Organic Compounds (ppb): . Grading
Methylene Chloride: ND-2200 . Cap Construction
Benzene: ND-980.000 l
Aniline: ND-3.900.000 I
Azobenzene: ND-12.000.000
Benzidine: ND-3.400.000
DCB: ND-3.500.000
.10-1 Carcinogenic Risk level
r-
Ozonation
Contaminated Groundwater or
Groundwater Extraction Equivalent
Treatment
. Upgrade Present Disch
System Effluent Dete
. Perpetual Operation Ope
to Contain Plume
. Cleanup Criteria Discharge to
lor Groundwater Big Black
Determined in Final Creek
Operable Units
. Lon~erm O&M - groundwater monitoring
- cap integrity monitoring
eachate generated
rom .
compaction during
construdion
. Institutional
Controls - deed restrictions on groundwater use
- access restridions
. 1o-e carcinogenic risk level assuming no failure of purge well system.
cap or institutional controls
. $12.091.000 Capital
. $429.000 Annual O&M
. $19.890.000 Present Worth
,
arge Standards
rmined in Final
rable Unit
. 1o-e Carcinogenic Level
. $1.218.000 Capital
. $357.000 Annual O&M
Time Until Cleanup Goals Met
I
Capping
=: 2 years
Groundwater
-------
To reduce water and wind-borne migration of contaminants off-
site, erosion controls will be used. As needed, dust suppression
techniques will be used to reduce airborne contaminant transport.
After the initial grading of the site, the area to be capped will
be further prepared. Initially, a foundation layer will be
formed using local or imported material capable of structurally
supporting the weight of the cap. This material will be spread
and graded to form a smooth subgrade prior to cap placement.
Final grading of the subgrade will be performed in accordance
with the proposed cap grades to provide positive surface drainage
off the cap. A drainage system will be constructed to collect
consolidation leachate.
The minimum post-compaction slopes for the cap will be 5 percent
where attainable; the maximum cap slope will be 25 percent. The
final capped area will rise approximately four feet above
existing grade. Stability of the soils on-site is not expected
to be a problem for the cap design for most of the site.
However, based on geotechnical testing, the sludges consist of
low-strength, highly compressible materials. These construction
concerns have been taken into account in the cap design and cost
estimate. After final grading is complete, the cap will be
fertilized, seeded, and mulched to promote vegetative growth.
Drainage pathways will 'be established to divert surface water
runoff away from the capped area on a permanent basis.
Groundwater Components
The groundwater is currently being pumpe~ using an existing
groundwater extraction system. For this remediation, the pumping
system would be upgraded to increase performance efficiency and
the distribution system would be relocated to accommodate excava-
tion and treatment of the lagoons. As previously mentioned, a
new treatment system would be built, using an ozone oxidation
treatment system or equivalent system to treat the groundwater.
The treated effluent would then be discharged to Big Black Creek.
In this alternative, the groundwater will be pumped and treated
perpetually to contain the groundwater plume.
~taJ.
Comconents
This al~ernative addresses all of the contaminated soils and
sludge.'in this operable unit through containment using capping
and groundwater extraction. Capping the eight source areas will
reduce air emissions and reduce infiltration of precipitation and
contaminants into the groundwater. However, the ~gduction in
infiltration will not be sufficient to achieve 10 risks for
groundwater or surface water ingestion. Therefore, the existing
pump and treat system will be operated perpetually and will
contain the groundwater contaminant plume to prevent groundwater
migration off-site and subsequent surface water contamination.
Institutional controls limiting on-site access and groundwater
-------
use will also be incorporated to prevent future development, site
access, and use of the contaminated groundwater. Placement of
the cap will involve alterations to the wetlands in source area
10.
This alternative is estimated to achieve a risk of 10-6, assuming
the cap, groundwater extraction and treatment system, and
institutional controls are successfully maintained. This
reElesents a five order-of-magnitude reduction in risk from the
10 initial risk.
The cap will require periodic inspection and repair. Periodic
sampling, inspection, and maintenance of groundwater monitoring
wells and the groundwater extraction system will be required. As
noted previously, the cap will be constructed to meet the intent
of RCRA subtitle C. Although RCRA is not applicable or relevant
and appropriate for this operable unit, the level of technology
required by RCRA is proposed to be used to provide an increased
level of protection.
Institutional controls on groundwater use and site access may be
difficult to enforce over an extended time period. There is
significant uncertainty over the likelihood that the institu-
tional controls, the cap, and the groundwater extraction and
treatment system will be operated, maintained, and enforced
forever.
The costs and estimated implementation time frame for Alterna-
tive 2 are:
;
capital:
Annual O&M:
Present Worth:
Estimated Implementation
Time:
$12 million
$429,000
$20 million
2 years
ARARs
Alternative 2 will comply with the substantive requirements of an
NPDES,p'4iarmit (Clean Water Act), which is an applicable ARAR.
Sinc8.~ands on the north side of Big Black Creek will be
impacted during the construction of this alternative, the
subst~iv. requirements of a 404 permit will need to be satis-
fied, a. well as the requirements of the state Wetland Protection
Act, also applicable ARARs. The state Soil and Erosion Act is
relevant and appropriate to this alternative, which is expected
to comply with the requirements of this ARAR. The Clean Air Act
and state Air Pollution Control Act are applicable to this
alternative during construction of the cap. This alternative is
expected to comply with the requirements of these ARARs. The
Safe Drinking Water Act is a relevant and appropriate ARAR and
the State Water, Resources Commission Act is an applicable ARAR to
this alternative because of discharge of treated groundwater to
-------
Big Black Creek. The requirements of these ARARs are anticipated
to be met by this alternative. According to the State of
Michigan, the Michigan Act 307 requirements may not be met.
Alternative 3: On-Site Incineration/Low TemDerature Thermal
DesorDtion. CaD. PumD and Treat Groundwater
Alternative 3 consists of combined treatment and containment
technologies directed toward removal and treatment of the most
contaminated sludges, and capping of less-contaminated sludges
and soils. The components of this alternative are presented in
Figure 4. The components presented in this figure are approxi-
mate and may be modified during design or construction.
Treatment Comconents
Source Areas 3 and 9: Sludge, berms, and soils under the sludge
will be excavated and incinerated on-site. Low-temperature
thermal desorption (LTTD) may be used on either or both of these
source areas or subareas if pilot-scale testing indicates accep-
table performance by achieving the cleanup criteria. LTTD is a
volume reduction technology that removes contaminants from the
sludge or soil by volatilization and concentrates the contami-
nants in an aqueous phase which is then treated. This technology
can provide a less-expensive alternative to incineration when
there is sufficient performance to achieve cleanup criteria.
Source Areas 6 and 8: Sludge and berms will be excavated and
incinerated. On-site LTTD may also be uped on either or both of
these source areas or subareas if pilot scale testing indicates
acceptable performance.
Source Area 10: Sludge and berms will be excavated and treated
on-site using LTTD.
Fluids generated during the construction of the cap from sludge
compaction in Source Areas 1, 5, and 7 will be treated in the
groundwater treatment system.
Fluid~ated during LTTD will be treated on-site using the
ground~~_. treatment system. Scrubber water from the incinera-
tor wil1 be treated by precipitation or equivalent treatment.
Filter cak. from filtering the LTTD wastewater will be incine-
rated in the on-site incinerator. The groundwater beneath the
site will be collected and treated using ozone or equivalent
treatment.
-------
Saurc8 ANa I. 5 and 7:
4.07-
. av-ConI8mNnlllllllbl:
MIII¥IM CNond8: ..0.:.1'
s.n-: NO-U
DCB: NO-93II.OOO
Aniline: No-.iO
A~: ND-11O.000
B8nDdin8: ND-a.IOO
Saurc8 ANa 3. I.
8. I. 8Ad 10 Sails AI-.d
~ 8Ad I.'. 8IId 10
SoU II8nNitIl.8gcIaM
15.5-
. av- c...--.....(llllbl:
MIII¥IM CNarid8: NO'
s.n-: NO-I20.000
DCB: 7.100-2.100.000
AnIIn8: ND-3.4OO
AJDbeN-: 711G-4111.000
88nJidne: NO-7.800
Saurc8 ,.,... 3. 6.
8. I. 8IId 10 SIudg8 8IId
Berm.:
100.800
. av- eo.-II llIIIbl:
M8f¥8n8 CNond8: No.;.2.21111
Ben-: N~.OOO
DCB: '0.500-2.900.000
AnIIn8: ND-3.900.000
AmI8IZ-: 18.500-12.000.000
BenDCan8: 6.500-3.400.000
Saurc8 AI8M 3 8IId 1
SooI s.-II SIudg8:
41.200 yeP
. av- Con\8mIn8III(llllbI:
.......... CNond8: NO'
Ben-: ND-I30
DCB: 76.01»-1.100.000
AnIIn8: 9.200-9.800
AmbenZ-: 74.01»-1.000.000
B8nDdin8: 5.500-690 ,OlIO
ConI8mIn8I8d
GnIuNM-
Time Until Cleanu Goals Met
.' 1
~
Soil
u-.IDft
~
ex-
".. .'
;
1..
Figure 4
Components of Alternative 3
o..-siI8 ~
~.I~
~
W-
.-I
. Upgr8d8 PIn8nI s,- .CI88nup Cri8Ii8 lor
~d8"-
.~...~ mined in FiMI'--
Ao.....dI88Id ... UnII
L no FiIl8r
L no Cond8nI8I8I
PtI8M Sep8r8IDf
.-I FIu8S
,
~
SubIII8 C Cap
(23_.
0iIctI8tg8 ..
~
. 1()-8 C8R:IIIIIgeftC uo'"
. $1,2\8.000 C8P'181
. $357.000Mnu8lOlM
Ca i
and Incinerationll TTO
. 5 years
. Long-4eRn O&M .
- groundwater monitoring
- cap inlegrily monitoring
. 1 ()-4 Carcinogenic Risk Level
. $74,416,000 Capilal
. $344.000 Annual O&M
. $79,912.000 Present Worth
Groundwaler
-------
containment ComDonents
All material
other source
the ash will
The cap used
native 2.
will be capped in Source Areas 1, 5, and 7. For the
areas, after incineration of the sludges and soils,
be replaced, then each source area will be capped.
in this alternative is the same as the cap in Alter-
Groundwater ComDonents
The groundwater component for this alternative is the same as the
component described in Alternative 2, except the groundwater will
be pumped and treated for a finite period. The cleanup criteria
for the groundwater will be determined in the final operable
unit.
General ComDonents
This alternative addresses all the contaminated soils and sludges
in this operable unit through a combination of treatment and
containment.
This alternative is expected to achieve a risk of 10-4 in the
groundwater, because the capping component can achieve only this
risk level since the reduction in preciE~tation migratioD4throug
the cap is not sufficient to achieve 10 risks. The 10 risk
reEfesents a three order-of-magnitude reduction in risk from the
10 initial risk.
Source Areas 1, 5, and 7 will be capped/and the remaining Source
Areas (3, 6, 8, 9, and 10) which contain the most contaminated
materials in the L.O.U. will be treated. Capping after treatment
of the sludges and replacement of the ash will reduce infiltra-
tion through the soils underneath the sludge. Placement of the
cap will involve alterations of the wetlands in source area 10.
This alternative involves capping approximately 23 acres of
contaminated sludges and soils and excavating and incinerating or
LTTD of approximately 56,800 ydJ of sludge and berms (Source
Areas~, 8, 9) and 41, 200 yd J of contaminated soil beneath the
la90o~~~c. Areas 3, 9) and LTTD approximately 44,000 yd3 of
sludq8Y'" berms (Source Area 10). LTTD is proposed to be used
in adcSi'ftDn.to incineration to reduce treatment costs. As
indica~.d previously, LTTD may be used on other source area
media, it pilot-scale testing indicates acceptable performance.
pilot-scale treatability testing will be needed to determine the
applicability of LTTD and treatability testing will most likely
also be needed for incineration.
-------
The costs and estimated implementation time frame for Alterna-
tive 3 are:
Capital:
Annual O&M:
Present Worth:
Estimated Implementation
Time:
$74 million
$344,000
$80 million
5 years
ARARs
The ARARs presented for Alternative 2 also are pertinent to this
alternative. In addition, air emissions requirements concerning
construction of equipment that may be a source of air emissions
in the Clean Air Act and Michigan Air Pollution Control Act are
applicable to this alternative. RCRA is a potential ARAR for
this alternative if the ash tests positive as a RCRA characteris-
tic waste. According to the state of Michigan, this alternative
does not satisfy Michigan Act 307 requirements.
Alternative 4: On-site Incineration/Low Temoerature Thermal
Desorotion. On-site Landfill. Pumo and Treat Groundwater
Alternative 4 also consists of combined treatment and containment
technologies directed to treatment of the most contaminated
sludges and land filling of less contaminated sludges and soils.
The components of Alternative 4 are presented in Figure 5. The
components presented in this figure are approximate and may be
modified during design or construction.
Treatment Comoonents
".
Source Areas 3. 6. 8. and 9: sludge and berms will be excavated
and incinerated on-site. LTTD may be used on these source areas
if pilot-scale testing indicates acceptable performance.
Source Area 10: Sludge and berms will be excavated and treated
on-site using LTTD.
Fluids generated during LTTD will be treated on-site using the
grounQw8ter treatment system. Filter cake generated during LTTD
will b~1ncinerated on-site. Scrubber water from the incinerator
will b8'~r.ated by precipitation or equivalent treatment.
Landfill leachate will be treated in the groundwater treatment
system.
The groundwater from beneath the site will be pumped and treated
using ozone or equivalent treatment.
-------
ScIurw AlMa I, 5 8IId 7:
45.500 rcP
. ~=-~~:
e.nan.: ND-a
DC8: NG-83O,ooo
Aniline: No-.&O
Amb8nz_: NO-11O,ooo
118n1ic1n8: NO-2. 100
SluwANa 3, I.
I. t. 8IId 10 Soi8 AIDn8
l~rcP
. 0Ig8nic ~ 1JI1Ib1:
~ CIIIDrid8: NO-
e.nan.: NO-I20.ooo
DC8: 7.100-2,700.000
Aniline: NO-3,400
Amb8nz_: 710-81.000
118n1ic1n8: N0-7,IOO
ScIurw ANa 3, I.
I, t. 8IId 10 SaiII .......
'1~:
. =:'='=*Jr*I:
B8n_: NO-I30
DC8: 7,1110-1,100.000
Aniline: N0-9.1OO
Amb8nz_: -,301)..1,000.000
88NIdne: NI)-.68O.ooo
ScIurw Ar8u 3, I, I. t,
8IId 10 SbIge 8IId 88nna:
100,100
. 0Ig8nic c:or.-. Ippbl:
........... CNorid8: No.;.2,2oo
e.nan.: NI>-9IO.ooo
DC8: 10,~.900.ooo
AnIline: N0-3.IIOO,ooo
Amb8nz_: 16,5110-12.000,000
118ru1Gn8: 6,5110-3.«10.000
~
Gra&.ndIr-
Time Until Cleanup Goals Met
Soil
E---..
....~
~
u.-
. Upgr8d8,",-~
. s,.-~1nI
....... CoIIIIIIiA';'-...
AIr I N18d
..
...188 1'1
Figure 5
Components of Alternative 4
0It-SiIt.1Ci. JfiIIIiW
... T.....-
TIw1nII 0I88piaR
Scn8IIIr
--
-.J
Resicbll Ash
Replaced
lTTD CcIndInNW
.........
FUll
DiIcIwve III
Bog IIt8dI
c..-
IncinerationA. TTO and Landlilli"!)
-s
~ DIIIIGMI
In ACAA SuIIII8 C
~
. 1()-4 C8R:IIMIg8fIic L8wI
. $1.2I1,oooC8pdal
. S357,oooAnnu8l04M
. Long-term 0&..
- groundwater monitoring
- cap and Ine,
inlegrily moniIoring
. 1G-4can:inogenic risk leve'
. $65.752.000 Capital
. $313.000 An..,... 0&"
. $70.874.000 Present Worth
Groundwater
.
-------
containment ComDonents
All material in Source Areas 1, 5, and 7, including sludge,
berms, and soils, will be excavated and placed in an on-site
RCRA-type landfill. The ash from incineration and LTTD (Source
Areas 3, 6, 8, 9, and ,10) will be placed in the on-site RCRA
landfill. Soils beneath and around the lagoons in these source
areas will be excavated and also placed in the landfill. The
approximate location of the landfill is presented in Figure 6.
Groundwater ComDonents
The groundwater component for this alternative is the same as
described in Alternative 3.
General ComDonents
This alternative also addresses all the contaminated sludges and
soils in this operable unit through a combination of treatment
and containment. The risks remaining a~~er remediation using
this alternative are estimated to be 10 . This alternative will
require the excavation and treatment of approximately 100,800 ~d3
of sludge and berms and landfilling of approximately 18,700 yd
of sludge. The approximate volume of soil to be landfilled is
334,700 yd3. The volume of ash from incineration and LTTD that
will be landfilled is 73,100 yd3. The total volume of material
that will be landfilled is approximately 426,506 yd3. The
landfill will occupy approximately 8 acres. A minimum of 12-feet
separation between the landfill base and the water table will be
provided. Landfil1ing of soils in sourde area 10 will impact the
existing wetlands.
The costs and estimated implementation time frame for Alterna-
tive 4 are:
capital:
Annual O&M:
Present Worth:
Estimated Implementation
Time:
$65,752,000
$313,000
$70,874,000
5 years
.".;..,;..,',.;"..,.....
ARAR&
The ARARs presented for Alternative 3 also are pertinent to this
alternative except Michigan Act 307 requirements would be met.
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The following nine criteria were used to evaluate the four
alternatives:
1.
OVerall protection of human health and the environment:
addresses whether a remedy provides adequate protection and
-------
~
~ . Approximate landfill location . .
Figure 6 LocatIon 01 HCRA landfill
. ~:'-~{;t\:~,....
-------
describes how risks posed through each pathway are elimi-
nated, reduced, or controlled through treatment, engineering
controls, or institutional controls.
2.
Compliance with applicable or relevant and appropriate
requirements (ARARs): addresses whether a remedy will meet
all of the ARARs of other Federal and state environmental
laws and/or justifies a waiver.
3.
Long-term effectiveness and permanence: refers to expected
residual risk and the ability of a remedy to maintain
reliable protection of human health and the environment over
time, once clean-up goals have been met.
Reduction of toxicity, mobility, or volume through treatment:
is the anticipated performance of the treatment technologies
a remedy may employ.
4.
5.
Short-term effectiveness: addresses the period of time
needed to achieve protection and any adverse impacts on human
health and the environment that may be posed during the
construction and implementation period, until clean-up goals
are achieved.
6.
Implementability: is the technical and administrative feasi-
bility of a remedy, including the availability of materials
and services needed to implement a particular option.
7.
Cost: includes estimated capital anft O&M costs, as well as
present-worth costs.
8.
state Acceptance:
is used to indicate the state's comments.
9.
community Acceptance: summarizes the public's general
response to the alternatives described in the Proposed Plan
and RI/FS Report. The specific responses to public comments
are addressed in the Responsiveness Summary section of the
ROD.
Thresha1d Criteria
OVerall Protection of Human Health and the Environment
Alternative 1 provides no protection, sinc!6no action is taken.
Alternative 2, even though it attains a 10 risk, is the next
least protective because no treatment of the principal threat is
included in the alternative. If failure of the cap, institu-
tional controls, or pump and treat system occurs because the
original source is still present, the site could return to
curren~6risk levels. In addition, in this alternative, achieving
the 10 risk estimate assumes that institutional controls and
groundwater pumping and treatment will be maintained forever, an
-------
unlikely event. Alternative 3 is more protective than Alterna-
tive 2 because of the treatment of sludge, berms, and soils, and
the finite groundwater pumP1ig and treatment period. However,
Alternative 3 presents a 10 risk, two orders of magnitude
greater excess cancer risk than Alternatives 2 and 4. This
greater residual risk is due to the use of capping only as a
containment technology, rather than in combination with perpetual
groundwater pumping and treatment. Alternative 4 is the most
protective because it provides treatment of highly contaminated
materials, high degree of containment of less contaminated
materials through landfilling rather than capping, and does not
require perpetual pumping and treatment of groundwater.
ComDliance with ARARs
The substantive provisions of the following have been identified
as ARARs for this operable unit:
Federal:
o
o
o
Clean
Clean
Flood
4321)
Water Act (33 U.S.C. 1251)
Air Act (42 U.S.C. 7401)
Plain Management and Protection of Wetlands (42 U.S.C.
state:
o
o
o
o
o
Water Resources Commission Act (ACT 245)
Goemaere-Anderson Wetland Protection Act (ACT 203)
Michigan Environmental Response Act ~(ACT 307)
Soil Erosion and Sedimentation Act (ACT 347)
Air Pollution Act (ACT 348)
The following have been identified as potential ARARS for this
operable unit:
o
o
Resource Conservation and Recovery Act (42 U.S.C.6901)
Safe Drinking Water Act (42 U.S.C. 300(f)
<'~:~I;';~. .
Federal.:-
The Clean Water Act (CWA) regulates the chemical, physical, and
biological integrity of surface waters. Under Title III and IV
of this act, effluent standards and permits are required to be
established and applied to discharges to surface waters.
Section 404 of Title IV specifically regulates the discharge of
dredged or fill material into surface waters, including adjacent
wetlands. Title 40, Part 129 of the Code of Federal Regulations
(40 CFR 129) establishes effluent standards and ambient water
criteria for certain toxic pollutants, including benzidine.
-------
Alternative 1, the no action alternative, will affect the water
quality of Big Black Creek, a recreational-use stream, since this
alternative involves the discontinuation of the groundwater
pumping and treatment system. Alternatives 2, 3, and 4 include
pumping, treating, and discharging groundwater on-site to the Big
Black Creek. Therefore, this regulation is applicable to all the
alternatives for the L.O.U. 40 CFR 122, 125 and 136 establish
guidelines and procedures for the National Pollutant Discharge
Elimination System (NPDES). The NPDES program is a national
program for issuing, monitoring, and enforcing permits for direct
discharges. The substantive requirements of these regulations
must be met for on-site discharges. Therefore, the substantive
requirements of these regulations are applicable to Alterna-
tives 2, 3, and 4.
40 eFR 230 regulates the disposal of dredged or fill material in
surface water and wetland areas. Alternatives 2, 3, and 4
involve excavation and other remedial activities in the wetland
area. Therefore, the substantive requirements of this regulation
are applicable to these alternatives. The MDNR has assumed
administration over the wetlands in the State of Michigan because
of Act 203 and several other environmental statutes which
incorporate these Federal requirements. However, the Federal
government retains the authority to review and comment.
section 10 of the Federal River and Harbor Acti as amended,
regulates the obstruction or alteration of any navigable water in
the united States. The jurisdiction of navigable waters includes
connected wetlands. Alternatives 2 and 3 include activities
which" will cause alterations in the wetland area of the Big Black
Creek by capping the wetlands in Source~rea 10. Alternative 4
includes activities which will cause alterations in the wetlands
by excavating the wetlands in Source Area 10. Therefore, the
substantive requirements of 33 CFR 320 through 330 may be
applicable to these alternatives.
The Safe Drinking Water Act (SDWA) of 1974, as amended, was
enacted to assure high water quality in public water systems.
The National Primary Drinking Water Regulations specify the
maximum contaminant levels (MCLs) and the maximum contaminant
level~a (MCLGs) for public water systems for inorganic and
organic--chemicals. The surface water in Big Black Creek is not
curr~ly distributed through the public water supply systems.
Therefor., these regulations are not applicable to the site.
However, the surface water is a potential source of drinking
water. Therefore, these standards may be relevant and
appropriate for Alternatives 1, 2, 3, and 4. Benzene is the only
compound of the compounds of concern which has a MCL and MCLG.
According to the final NCP, MCLGs which have values of zero are
not relevant or appropriate at CERCLA sites (55 FR 8751) .
Since the MCLG for benzene is zero, this standard is not
relevant or appropriate to the L.O.U. The MCL for benzen~6is
5 ppb, which is equivalent to an excess cancer risk of 10 .
-------
Lagoon 3 soil and sludge and Lagoon 9 soil around the lagoon may
result in an excess cancer risk of benzene in surface water at
the same order of magnitude as the MCL. Based on this informa-
tion, Alternative 1, the no action alternative, may not comply
with MCLs. However, Alternatives 2, 3, and 4 are expected to
comply with MCLs.
The Clean Air Act (CAA) was enacted to protect and enhance air
quality. 40 CFR 6 requires that all Federal projects, licenses,
permits, plans, and financial assistance. activities conform to
any state Air Quality Implementation Plan (SIP). This require-
ment is action specific and therefore, is applicable to Alterna-
tives 2, 3, and 4. 40 CFR 50 establishes primary and secondary
ambient air quality standards. Since these requirements regulate
ambient air quality, these rules are applicable to all the
alternatives. It is expected that all the alternatives, except
Alternative 1, will be able to attain primary and secondary air
quality standards. 40 CFR 60.50-54 specify emission standards
for newly constructed incinerators. These rules are only
applicable to Alternatives 3 and 4 which include incineration of
soil and/or sludge and berms as part of the remedial alternative.
These alternatives are expected to comply with 40 CFR 60.50-54
rules. 40 CFR 61 specifies national emission standard for
hazardous air pollutants from stationary sources. The hazardous
air pollutant at this site specified under these regulations is
benzene. This regulation is applicable to Alternatives 3 and 4
which contain treatment systems for the groundwater, soil, and/or
sludge and berms which may emit hazardous air pollutants.
u.S. EPA's policies and procedures for zmplementing Executive
Orders 11988 (Floodplain Management) and 11990 (Wetlands Protec-
tion) and the Fish and Wildlife Coordination Act are provided in
40 CFR 6. The procedures provided in 40 CFR 6, Appendix A,
substantively require that U.S. EPA conduct its activities to
avoid long- and short-term adverse impacts associated with
actions in the wetland or floodplain areas. Because Alterna-
tives 2 and 3 involve capping in a portion of the wetland area
and Alternative 4 involves excavation in a portion of the wetland
area, .g~~pliance with the Wetland Act must be met for these
alte~.~.. and will require close interaction with the appro-
priat~.~atory agencies.
~'.
The Re80urce Conservation and Recovery Act (RCRA) is a potential
ARAR for Alternatives 3 and 4. After treatment in these alterna-
tives, the resulting ash may exhibit the characteristic of
toxicity for metals through TCLP testing, since metals may be
concentrated in the ash and their mobility increased. This will
be confirmed during the design phase. If the ash is a RCRA
characteristic waste, then Alternatives 3 and 4 must comply with
RCRA regulations concerning disposal.
-------
state
The Water Resources Commission Act was established to protect the
water quality of Michigan. Part 4 rules establish surface water
quality standards and regulate discharge to surface water bodies.
since surface water quality would be affected by the no action
alternative, Alternative 1 does not comply with these. water
quality requirements. Alternatives 2 through 4 include ground-
water pumping and treatment followed by discharge to Big Black
Creek, a recreational-use stream. Rule. 323.1057 (Rule 57) of
Part 4 establishes standards for toxic substances. Standards for
toxic substances are established on a site-specific basis.
NPDES permits are regulated by the State under the Part 4 Water
Quality rules. Because all remedial activities occur on-site,
permits are not required; however, the substantive requirements
of the NPDES permit will be met.
Act 203, the Goemaere-Anderson Wetland Protection Act, applies to
activities that result in discharge to the wetland area that
drains to the Big Black Creek. In Michigan, the MDNR has juris-
diction over the wetlands. All the alternatives result in
discharge to, excavation, or grading of a portion of the wetland
area of the Big Black Creek south of Lagoon 10 in some form. The
no action alternative may detrimentally affect the wetland area
by natural discharge of contaminated groundwater into the
wetlands. Therefore, this alternative may not comply with the
Wetland Protection Act. Alternatives 2, 3, and 4 include
remedial activities, i.e. excavation and/or filling in the
wetland area. These activities must meet the substantive
requirements of the Wetlands Protection~ct. Compliance with the
substantive standards of the Wetland Act must be met for
Alternatives 2, 3, and 4 and will require close interaction with
the appropriate regulatory agencies.
The substantive provisions of Parts 6 and 7 of the rules
promulgated under the Michigan Environmental Response Act (Act
307) are considered an ARAR for the remedial action to be
undertaken at this site. These rules provide, inter alia,
that remedial action be protective of human health, safety and
the environment, (Rule 299.5705 (1». The rules specify that
this8tlbaard is achieved by a degree of cleanup which conforms
to one-or aore of three cleanup types (Rule 299.5705(2». A type
A cleanup generally achieves cleanup to background (Rule
299.5707): a type B cleanup meets specified risk-based levels in
all media (Rule 299.5709); and a type C cleanup is based on a
site-specific risk assessment which considers specified criteria.
The selected remedy meets this ARAR.
The Soil Erosion and Sedimentation Act establishes general soil
erosion and sedimentation control procedures and measures for
specified activities which disturb one or more acres of land or
is within 500 feet of a lake or stream. Because the activities
-------
specified in Part 17 rules are not the activities which directly
correspond to the remedial alternatives, these rules are not
applicable to the alternatives for the L.O.U. However, Alterna-
tives 2, 3, and 4 will. disturb one or more acres of land and are
within 500 feet of a stream. Therefore, the requirements of
these rules are sufficiently similar to the site that they are
relevant and appropriate. It is expected that Alternatives 2, 3,
and 4 will comply with the requirements of Part 17 Soil Erosion
and Sedimentation rules.
The Air Pollution Control Act was enacted to control air pollu-
tion in Michigan. Part 2 Air Use Approval rules establishes
requirements for the installation or construction of equipment
which may be a source of an air contaminant. Alternatives 2, 3,
and 4 include ozonation for the groundwater. Alternatives 3 and
4 include LTTD and incineration of soil and/or sludges and berms.
These treatment systems may be sources of air contaminants,
therefore, Part 2 rules are applicable. Alternatives 2, 3, and 4
are expected to comply with the requirements of these rules.
Part 3, Emissions Limitations and Prohibitions for Particulate
Matter, establishes standards for the density of emissions and
emission of particulate matter. Alternatives 2, 3, and 4 include
activities which are sources of particulate matter, i.e.
processing, using, storing, transporting and/or conveying bulk
materials. Therefore, these rules are applicable to Alterna-
tives 2, 3, and 4. It is expected that these alternatives will
comply with the requirements of these rules. Part 7, Emission
Limitations and Prohibitions for New Sources of Volatile Organic
Compound Emissions provides general provisions for new sources of
volatile organic compound emissions. AYternatives 2, 3, and 4
may provide VOC emissions. Therefore, these rules are applicable
to these alternatives. It is expected that Alternatives 2, 3,
and 4 will comply with requirements of Part 7 rules. Part 9
Emissions Limitations and Prohibitions prohibits the emission of
an air contaminant or water vapor in a quantity that causes
injurious effects to human health and the environment. From the
risk assessment, the L.O.U. may provide an unacceptable risk to
human health and the environment via the air route of exposure.
Part 9. rules are applicable to the no action alternative, and
this ~ative does not comply with the requirements of these
rule.~:~'W1~ appropriate emissions controls, Alternatives 2, 3,
and 4 ~expected to comply with these rules. Part 10, Inter-
mitten~an4 Sampling rules give the commission the authority to
require performance tests of any source of an air contaminant.
Performance tests can be performed only on unit processes.
Therefore, these rules are applicable to Alternatives 2, 3, and 4
which include treatment systems. It is expected that these
alternatives will comply with intermittent testing and sampling
if and when the commission requires performance tests.
-------
PrimarY Balancinq Criteria.
Lonq-Term Effectiveness and Permanence
The evaluation of alternatives under this criterion addresses the
risk remaining at the site after response objectives have been
met. The primary focus of this evaluation is the extent and
effectiveness of the controls that may be required to manage the
risk posed by treatment residuals and/or untreated wastes.
Alternative 1 provides no long-term effect!yeness and would
result in continuation of the evaluated 10 risk levels that
exist at the Bofors site. Alternative 2 provides for insti-
tutional controls and permanent extraction and treatment of
groundwater as a means of perpetually managing the site. The
reliability of controls for this alternative for the most part
depend on the successful implementation of institutional controls
on the use of groundwater as a drinking water source and
continuation of groundwater pumping and treatment forever. There
will likely be difficulties in implementing and maintaining these
institutional controls and perpetual groundwater remediation.
Alternative 3 remediates the more contaminated areas of the
Bofors Site. Alternative 3 requires a finite groundwater extrac-
tion and treatment period, bU~4compromises the_gleanup level
attained in groundwater to 10 rather than 10' because of the
use of capping. Therefore, the residual risk of Alternative 3
must be recognized as two orders of magnitude greater than
Alternatives 2 and 4. Alternative 4 is the most comprehensive of
the alternatives relative to long-terw ~sks. This alternative
is projected to be able to attain 10 risk levels. This
alternative, like Alternative 3, minimizes long-term management
because the purge well and treatment system will be turned off
eventually. In addition, Alternative 4 uses a higher degree of
containment (landfilling), than Alternative 3 (capping).
Reduction of Toxicitv. Mobilitv. or Volume Throuqh Treatment
This evaluation criterion addresses the statutory preference for
selectiQ9 remedial actions that employ treatment technologies
that pilianently and significantly reduce toxicity, mobility, or
volum.-d the untreated wastes. The preference is toward
treat.eD~ processes which result in destruction of toxic
contaminants, reduction of toxic contaminants total mass,
irreversible reduction in contaminant mobility, or reduction of
total volume of contaminated media.
-------
All alternatives except Alternatives 1 and 2 provide, to varying
degrees, permanent and irreversible reduction of contaminants.
No significant destruction of toxic components or reduction in
total volume is achievable in Alternative 2. Alternatives 3 and 4
employ both containment and treatment technologies with treatment
of the principal threat.
Alternatives 3 and 4 include on-site treatment technologies
(incineration and LTTD) capable of significantly and irreversibly
reducing the toxicity and volume of the untreated source wastes.
The landfill component of Alternative 4 provides only permanent
containment, not destruction or reduction in volume. However,
this containment is more protective than the capping in Alterna-
tive 3, because the landfill has a cap and a bottom liner system,
providing a greater degree of containment.
Short-Term Effectiveness
This evaluation criterion addresses the effects of the alterna-
tive during the construction and implementation phases until
remedial response objectives are attained. Under this criterion,
alternatives are evaluated with respect to their effects on human
health and the environment.
Short-term effectiveness is not applicable to Alternative 1 sine
there is no remediation in this alternative. Alternative 2 does
not require excavation of contaminated material and therefore has
a lower potential risk to the on-site workers and the nearby
community. Some grading will be required that may generate some
air-borne contamination that must be corttrolled. Alternatives 3
and 4 both require excavation of contaminated material which
could generate air-borne contamination. Alternatives 3 and 4
also have the potential for air emissions from the incinerator
and LTTD units. Air emissions contr~ls will be implemented on
these systems as needed and these alternatives would be subjected
to community health and safety work plans for controlling
fugitive dust and air emissions and potential exposures.
Considerinq the time required for protection and the time until
the r8iil1al action objectives are met, Alternative 2 requires
perpetual~qroundwater extraction and treatment and is essentially
a manag...nt alternative that requires the establishment of a
permanent treatment facility, monitoring plan, site security,
etc. In contrast, Alternatives 3 and 4 require a finite period
of time for groundwater extraction and treatment. This can be
more easily managed. Both Alternative 3 and 4 are expected to
-------
require approximately the same remediation time period of 5 years
(not including the time to pump and treat groundwater).
ImDlementabilitv
This criterion addresses the technical and
feasibility of implementing an alternative
of various services and materials required
tation.
administrative
and the availability
during its implemen-
Technically, all site alternatives are easily implemented and
readily constructed of available materials. The technologies
considered (which include incineration, LTTD, capping, and
pumping and treatment of groundwater) are available from
commercial vendors. Those alternatives which employ incineration
and LTTD simultaneously present moderate site restrictions. As a
result of space constraints, these processes must be separated,
therefore construction will occur on opposite sides of the Bofors
site, warranting careful coordination between these construction
phases.
Groundwater treatment systems and long-term monitoring will be
required for each remedial alternative and do not present
constraints on implementation. However, approval of institu-
tional controls placed on groundwater under Alternative 2 may be
difficult to obtain, and the long-term reliability of these
controls is questionable.
,..
All remedial actions in Alternatives 2, .3, and 4 are proposed to
take place on-site. Therefore, no actual permits are required;
however, the substantive requirements of permits must be met.
Coordination with the local community may be required to ensure
the acceptability of incineration and LTTD in Alternatives 3 and
4 and the substantive requirements of the air permit will need to
be met for air emissions from implementation of these two
alternatives.
~~.
Capitar~ annual O&M, and present worth costs are summarized in
Table 14. Alternative 4 is the least expensive alternative of
the alternatives that provide treatment of the contaminated
material. Alternative 2 is less expensive than Alternative 4 but
contains no treatment of the principal threat and requires
perpetual pumping and treatment of the groundwater for contain-
ment of the plume.
-------
TABLE 14
ALTERNATIVE COST SUMMARY
Bofors Site
Muskegon, Michigan
AItW~. 10tal Present Risk Remaining
After Pathways
Alternative ~ns Capital Cost O&M Cost Worth Cost* Remediation Remedlated
Alternative 1 No Action. --- $27,000 $484,000 10-1 None
Alternative 2 Capping, Groundwater Institutional $12,091,000 $429,000 $19,890,000 1 ()-6 SW,A
Controls, Pump & Treat Ground-
water Perpetually.
Alternative 3 Capping, Incineration, L TTO, Pump $74,416,000 $344,000 $79,912,000 10-4 GW, SW, A
and Treat Groundwater for Finite
Period.
Alternative 4 Incineration, l TTO, landfill, Pump $65,752,000 $313,000 $70,874,000 1 ()-6 GW, SW, A
and Treat Groundwater for Finite
Period.
NOTES:
.,
* 1 Present Worth based on perpetual pump and treat for Alternatives 2 and 4; 43 years of pump and treat for other alternatives; variable times for flushing
options depending on time to enectively reduce contaminant concentrations; all present worth costs are calculated using an interest rate 5.5%. Cap
and landfill options provide Iong-tenn O&M for periods equal to the pump and treat times. 43-year groundwater pump and treat period is approximate
only and based on preliminary evaluations. This will be evaluated further in the Groundwater Operable Unit Feasibility Study.
2 The present worth analysis is used to evaluate expenditures that occur over different time periods by discounting all future costs to a common base
year. This allows the cost of remedial action alternatives to be compared on the basis of a single figure representing the amount of money that. if
invested in the base year and disbursed as needed, would be sunicient to cover all costs associated with the remedial alternative over its planned
life.
Ahernative 1 costs represent long-tenn monitoring.
Costs assume sludge. berms, and soils beneath the lagoons are contaminated above 1(}-6 risk level to the water table. Soils around are assumed
to be contaminated above 1 (}-6 risk level only in the top 5 feet.
GW: Grour
ter.
SW: Surface water.
-------
Modifvina criteria
state Acceptance
The state of Michigan has indicated it's acceptance of
Alternative 4 for remediation of the L.O.U. at the Bofors site
and a letter of concurrence is forthcoming.
Community Acceptance
There were several comments received from the community during
the public comment period. In summary, two who commented
perceive that there is a high level of cancer mortality in the
area and that more needs to be done to protect the community.
The third expressed that money could be spent on "better
priorities" than expanding wastewater facilities, and suggested
the use of bacteria to "eat up" contaminants. Several commenters
expressed objections to the use of incineration. However,
U.S. EPA is confident that the remedy will be protective of human
health and the environment. The complete comments are addressed
in the attached Responsiveness Summary.
THE SELECTED REMEDY
Based upon consideration of the requirements of CERCLA, the
detailed analysis of the alternatives, and public comments, both
U.S. EPA and the State have determined that Alternative 4:
Excavation, On-site Incineration/Low-Temperature Thermal Desorp-
tion, On-site Disposal, and pumping and 1reatment of Groundwater
is the most appropriate remedy for the Bofors site in Muskegon,
Michigan.
Approximately 100,800 cubic yards (yd3) of most-contaminated
sludge will be excavated from the lagoon area. The organic
compounds in the sludge will be treated using incineration and
low-temperature thermal desorption technologies. Approximately
64 percent of the organic compounds will be removed by this
treatment process. The treated sludges will be landfilled in an
RCRA l~dfill. It is estimated that 73,100 yd3 of treated ash
will ~andfilled. Approximately 334,700 yd3 of less-contami-
nated slQdq8S and soils will also be excavated and placed in the
RCRA laDdfill. This landfill will occupy approximately 8 acres
in the lagoon area.
Remediation Goals
The purpose of this response action is to control risks posed by
migration of organic compounds to groundwater and surface water
and through air. Existing conditions at the site have E!en
determined to pose an excess lifetime cancer risk of 10 from
ingestion of contaminated groundwater. This risk relates to the
organic compound concentrations (primarily benzidine and DCB) in
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TABLE 15
COST SUMMARY FOR THE SELECTED REMEDY
CAPTIAL COSTS:
Cost
Site Work
1. Site Preparation
2. Soil Excavation
3. Materials Transport
4. Materials Processing/Size
5. Site Monitoring
Reduction
S 2,090,400
S 4,731,000
S 2,752,400
S 555,400
S 7,241,000
Treatment Component
1. On-site Incineration
2. On-site LTTD
3. Pumping and Treatment Systems
S15,035,100
S11, 3.0,000
S 1,218,200
Containment Component
1. On-site Secure Landfill
2. Indirect Capital Costs
S 6,387,600
Sl-1,383,2JO
Subtotal
565,752,000
;
OPERATION AND MAINTENANCE COST:
1. Landf i 11 O&M
Leachate Pump & Treat: combined
wi~h groundwater pump' treat:
1.2 million gallons per year
Maintenance of Cap and Leachate
uU:!j;.~~..
eftvirOn8ental Monitoring
System
S 5,000/1'1:'
S 22,OOO/yr
S 10,000/)'r
S 10,000/1'1:'
Subtotal
5 ~7,OOO/yr
2. Pump and Treat O&M
S266,OOO/vr
Subtotal
5313,000/yr
Note:
Detail cost breakdowns are in Appendix F .~ the Feasibility Study.
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~
the sludges. Since no Federal or State chemical-specific ARARs
exist for sludge and soil that specify concentrations, the action
level for the organic compounds in sludge and soil was determined
through a site-specific analysis. This analysis used fate and
transport modeling to determine levels to which organic compounds
in sludges and soils should be reduced in order to ensure no
migration of contaminants to th6 primary pathways of groundwater,
surface water, or air above 10 levels.
The excavated contaminated sludges and berms will be treated
using incineration and low-temperature thermal desorption which
will remove approximately 64 percent of the organic compounds
from the sludge and berms. The ash from treated sludge and berms
will be excavated and landfilled in a on-site landfill that will
meet the intent of RCRA subtitle C requirements, along with the
less contaminated soils beneath and around the sludge.
A breakdown of capital, annual O&M, and present-worth costs for
the selected remedy are presented in Table 15.
THE STATUTORY DETERMINATIONS
Under its legal authorities, U.S. EPA's primary responsibility at
Superfund sites is to undertake remedial actions that achieve
adequate protection of human health and the environment. In
addition, section 121 of CERCLA establishes several other
statutory requirements and preferences. These specify that when
complete, the selected remedial action for this site must comply
with applicable or relevant and appropriate environmental
standards established under Federal and state environmental laws
unless a statutory waiver is justified. ' The selected remedy also
must be cost-effective and utilize permanent solutions and
alternative treatment technologies or resource recovery
technologies to the maximum extent practicable. Finally, the
statute includes a preference for remedies that employ treatment
that permanently and significantly reduce the volume, toxicity,
or mobility of hazardous wastes as their principal element. The
following sections discuss how the selected remedy meets these
statutory requirements.
prote~of Human Health and the Environment
The s~~~ remedy protects human health and the environment
througIJtreatment and landfilling of organic compound contami-
nated sludge, and landfilling the soils in the lagoon area. The
landfill will be constructed to meet the intent of RCRA Subtitle
C landfill requirements to reduce the likelihood of contaminant
migration.
Treatment of the most con~~minated sludge also will reduce the
risks to less than 1 x 10 . This level_!s within6the range of
acceptable exp~sure levels of between 10 and 10 . By land-
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filling the contaminated soils, the risks of ingestion of ground-
water contaminated from the soils will be further reduced. There
may be short-term threats associated with the selected remedy
during excavation; however, these can be controlled. No adverse
cross-media impacts are expected from the remedy.
ComDliance with ARARs
The selected remedy of excavation, on-site thermal treatment, and
landfilling will comply with all chemical-, action-, and
location-specific ARARs. The ARARs are presented below.
Action-SDecific ARARs:
Clean Water Act (CWA) of 1977, as amended [33 U.C.S. 1251]
40CRF122 + 40CRF125 - The National Pollutant Discharge
Elimination System (NPDES), which specifies the scope and
details of the NPDES permit applications, including limita-
tions, standards, and other permit conditions which are
applicable to all permits including specified categories of
NPDES permits. Also specifies schedules of compliance and
requirements for recording and reporting monitoring results.
Act 348 of the Public Acts of 1965, as amended:
tion Act
Air Pollu-
Part 2 - Air Use Approval, which specifies information
required for a permit to install, cqnstruct, reconstruct,
relocate, or alter any process, fuel burning or refuse
burning equipment, or control equipment which may be a source
of an air contaminant.
Chemical-SDecific ARARs:
Clean Water Act (CWA) of 1977, as amended [33 U.C.S. 1251]
40CFR129 - Toxic Pollutant Effluent Standards, which estab-
lishe. toxic pollutant effluent standards and prohibitions of
spC~1ic compounds for specified facilities discharging into
navigable waters. 40CFR129.104 sets the ambient water
cri~.rion for benzidine in navigable water as 0.1 ug/l.
Public Health Service Act: Title xrv, as amended by the Safe
Drinking Water Act [42 U.S.C. 300(f)] (Potential ARARs)
40CFR141 - National Primary Drinking Water Regulations, which
specify maximum chemical contaminant levels (HCLs) of public
water systems for inorganic and organic chemicals, maximum
contaminant level goals (HCLGs) of pUblic water systems for
organic chemicals, and establishes national revised primary
drinking water regulations of HCLs for organic chemicals.
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Clean Air Act of 1963, as amended [42 U.S.C. 7401]
40CFR50 - National Primary and Secondary Ambient Air Quality
Standards, which establish national primary and secondary
ambient air quality standards. The appendices provide
methods and procedures for measuring specific air pollutants.
40CFR60 - Standards of Performance for New Stationary
Sources, which indicate applicability, sets particulate
matter effluent standards, specifies monitoring requirements,
and outlines test methods and procedures for incinerators.
40CFR61 - National Emission Standards for Hazardous Air
pollutants, which identifies substances that have been
designated hazardous air pollutants, and for which a Federal
Register notice has been published, and specifies prohibited
activities, describes procedures for determining whether
construction or modification is involved, prescribes methods
of applying for approval, and covers manner in which start-up
notification is to be provided.
Act 245 of the Public Acts of 1929, as amended:
Resources commission Act
Water
Part 4, Rule 57 - Water Quality Standards (Surface Water
Quality Standards), which establishes limits for all waters
of the State for the following components: dissolved solids,
pH, taste and odor producing substances, toxic substances,
total phosphorous and other nutrienis, and dissolved oxygen.
Act 348 of the Public Acts of 1965, as amended:
tioD Act
Air Pollu-
Part 3 - Emission Limitations and Prohibitions - Particulate
Matter, which establishes standards for the density of
emissions and emission of particulate matter.
A~~07, Michigan Environmental Remediation Act, sets
r"",..ents for remediation of hazardous waste sites in
M~an. There are three types of remediation specified by
tlti~act: Type A, B, and C.
.
Loca~ioD-SDecific ARARs:
Clean Water Act (CWA) of 1977, as amended [33 U.C.S. 1251]
33CFR322 - Permits for structures or Work in or Affecting
Navigable Waters of the United states, which provide proce-
dures for the C.O.E. for reviewing permits to authorize
structures or work affecting navigable water, including
wetland areas.
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Floodplain Management, and 11990, Protection of Wetlands [42
U.S.C. 7401]
40CFR6 - Procedures for Implementing Requirements of the
Council on Environmental Quality on the National Environ-
mental POlicy Act, which provide policies and procedures for
floodplain management and wetland protection.
Act 203 of the Public Acts of 1979: . The Goemaere-Anderson
Wetland Protection Act - These rules apply to activities that
result in discharge to the wetland area that drains to the
Big Black Creek. These rules include permitting require-
ments, wetland determination, and mitigation.
Act 347 of the Public Acts of 1972:
Sedimentation Control Act
Soil Erosion and
Part 17 - Soil Erosion and Sedimentation Control - Estab-
lishes general soil erosion and sedimentation control
procedures and measures. Also, specifies earth change
requirements and soil conservation district standards and
specifications.
other criteria. Advisories or Guidance to be Considered
(TBCs): .
None.
Cost-Effectiveness
~
The selected remedy is cost-effective because it has been
determined to provide overall effectiveness proportional to its
costs, the net present worth value being $70,000,000. The
estimated costs of the selected remedy are within an order of
magnitude of the costs associated with treatment of sludge and
on-site capping of the contaminated soils, and yet the selected
remedy assures a lower residual risk after remediation is .
complete and higher degree of certainty that the remedy will be
e~fe~t!D.' ,in the long-term since more complete containment (land-
fl.ll~n81. used.
._~..-
util~on of Permanent Solutions and Alternative Treatment
Technoloaies (or Resource Recoverv Technoloaies) to the Maximum
Extent Practicable
u.S. EPA and the State of Michigan have determined that the
selected remedy represents the maximum extent to which permanent
solutions and treatment technologies can be utilized in a cost-
effective manner for the lagoon area operable unit at the Bofors
site. Of those alternatives that are protective of human healtt
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"
and the environment and comply with ARARs, u.s. EPA and the state
have determined that this selected remedy provides the best
balance of tradeoffs in terms of long-term effectiveness and
permanence, reduction in toxicity, mobility, or volume achieved
through treatment, short-term effectiveness, implementability,
cost, also considering the statutory preference for treatment as
a principal element and considering state and community accep-
tance.
The selected remedy offers a high degree of long-term effective-
ness and permanence since incineration is being used.
The selected remedy treats the principal threats posed by the
sludges, achieving significant organic compound reductions
(60 percent). The implementability of the selected remedy is
comparable to the nontreatment alternatives. The selected remedy
is also the least costly of the two alternatives.
The selection of treatment of the contaminated sludges is consis-
tent with program expectations that indicate that highly toxic
and mobile waste are a priority for treatment and often necessary
to ensure the long-term effectiveness of a remedy. Since the
selected remedy has the most complete containment, this remedy is
anticipated to have th~ best long-term effectiveness and
permanence and is therefore determined to be the most appropriate
solution for the contaminated sludges and soils at the Bofors
site.
Preference for Treatment as a princical Element
r
By treating the contaminated sludges in a thermal destruction
unit and landfilling the ash and contaminated soils, the selected
remedy addresses one of the principal threats posed by the site
through the use of treatment technologies. Therefore, the
statutory preference for remedies that employ treatment as a
principal element is satisfied.
.~:~t~..
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....' .4i;,
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RESPONSIVENESS SUMMARY
The Remedial Investigation/Feasibility study (RI/FS) and the
Proposed Plan for the BOfors-Nobel site were made available to
the public in July, 1990. The notice of availability for these
two documents was published in the Muskeqon Press on July 23,
1990. A public comment period was held from July 23 through
August 23 and a public meeting was held on August 1, 1990. At
this meeting, representatives from U.S.EPA and the Michigan
Department of Natural Resources (MDNR) answered questions about
problems at the site and the remedial alternatives under
consideration. Three comments were submitted at the public
meeting and several comments were received in the mail prior to
August 23, 1990, the last day of the public comment period.
Following are all the comments received and u.s. EPA's response
to each comment. .
Comment
The first comment related to contamination
chemical company and the fact that several
community have died of cancer.
in the air from the
people in the
Response .
There are several chemical companies and several Superfund sites
in the area and the Michigan Department of Public Health is
pursuing this issue.
Comment ~.
The second comment or felt the proposed alternative is not
protective enough, particularly concerning air exposure during
remediation. She indicated more should be done.
Response
U.S. EPA is very sensitive to the concerns of the pUblic and
believes the selected remedy is the most protective and will
alleviate any air emissions from the lagoon site as part of the
remedy. Because of the highly toxic nature of the material on
site, ,~..alternative uses incineration to destroy the most
hazar~'waste. State of the Art technology will be used to
elimina~-hazardous air emissions. Extensive air monitoring will
be performed to ensure control of air emissions during
construct:ion.
Comment
The third commenter questioned if bacteria could be used to eat
up the contamination and suggested bioremediation was not
selected due to costs.
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\J
Response
In fact, biological treatment methods were considered and
screened out early because they will not work efficiently and
are not cost effective. 3,3'-Dichlorobenzidine (DCB), which is
one of the major contaminants at the site, is present at the site
in a crystalline form. DCB requires the transfer from a
crystalline form into an aqueous matrix which would require a
soil washing pretreatment step. Soil washing treatability
studies have indicated that this technology cannot adequately
remove DCB from soil. In addition, heavy metals such as zinc,
chromium, and lead which are present at the site, can be toxic to
the microorganisms and additional treatment would probably be
needed for metal contamination. In both cases the concentrations
of contaminants are very high and the waste would be very
difficult to bioremediate.
Comment
Several commentors objected to incineration based on information
provided by the West Michigan Region Environmental network
concerning uncertainties, hazards and health risks associated
with incineration.
Response
As previously mentioned, u.s. EPA is very sensitive to the
concerns of the community. The agency believes the selected
remedy provides the best protection the u.S. EPA can provide.
Contrary to the information the citizens were given, incineration
will destroy the hazardous compounds and the incinerator will be
operated in such way to insure total de~ruction. Extensive
testing prior to start-up including treatability studies and
trial burns will be performed to determine the correct operating
procedures for the incinerator. This extensive testing is
designed to overcome the uncertainties involved in treatment of
hazardous waste. Extensive monitoring including air emissions
and other operating parameters will be performed to evaluate
incinerator performance and corrections will be made as
necessary.
Comment
sever." entors expressed concern over the fact the
groun . will not be addressed until much later.
'''~~.~
R ... "',
esponj-~l -
In fact, the contaminated groundwater is currently being
controlled by a pump and treat system which will be upgraded
during this remedy. In addition, the groundwater Remedial
Investigation/Feasibility Study (RI/FS) is currently underway.
Comment
A few citizens were concerned that the pollutants will drift into
populated areas, especially the Carr Elementary School.
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Response
The response to the comment regarding objection to incineration
applies to this comment.
Comment
One comment or stated that all landfills leak and
the material landfilled on site. This commentor
excavate and transport the hazardous material to
(emphasis added) landfill.
does not want
suggested we
an offsite
Response
Because it is known that landfills may leak, the U.S. EPA has
selected technology that provides the most protective type of
landfill. The landfill design that will be used in this remedy
will consist of a double lined containment system with a leachate
collection system between the two liners to prevent migration of
any leachate that might be generated. In addition the landfill
cap will be constructed to prevent infiltration of any
precipitation so that leachate generation is minimized.
Furthermore, there will be a detection system below the bottom
liner to provide backup monitoring for the system. In addition,
the majority of contamination will be destroyed through the
incinerator and the less contaminated material will be
landfilled.
The Comprehensive Environmental Response, Compensation, and
Liability Act of 1980 (CERCLA) as amended by the Superfund
Amendments and Reauthorization Act of 1986 (SARA) states in
section 121(b) (1) that remedial actions)n which treatment which
permanently and significantly reduces the volume, toxicity or
mobility of the hazardous substances, pollutants, and
contaminants, are to be preferred over remedial actions not
involving such treatment. The offsite transport and disposal of
hazardous substances or contaminated materials without such
treatment should be the least favored alternative remedial action
where practicable treatment technologies are available. u.S. EPA
does not recommend offsite landfilling of the hazardous material
because it would not comply with the law as incineration is a
proverf"t.eChno1ogy .
,..""",;""" .
Comment:-
One person indicated it is a disgrace that the Responsible
Parties wriggle out of cleaning up the site.
Response
It has not been established that liable parties exist for this
site. u.S. EPA will continue to explore the possibility of
naming potentially Responsible Parties in the future.
Comment
Several commentors requested an extension on the second to the
last day of the comment period.
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Response
The National Contingency Plan (NCP) allows for a 30 day extension
to a public comment period if requested in a timely manner. The
NCP defines a "timely" request as generally being within 2 weeks
after the initiation of the public comment period. u.s. EPA does
not believe a delay in this project will benefit the community.
The protection of public health and the environment will better
be served by moving ahead with the design and clean-up of this
site.
,
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