United States
.Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R05-88/073
September 1988
&EPA
Superfund
Record of Decision
U.S. Aviex, Ml
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. - "•-'J'"" '"'-'• 2- , 3. R»c.oi«nt's Accession No.
PAGE ; SPA/ROD/R05-38/073 , I
4. Till, and Subtitle | 5. Report Oft,
SUPERFUND RECORD OF DECISION i 09/0//3S
U..S. Aviex, MI
First Remedial Action - Final
Author(j) 3. Performing Organization Reot. No
i. Performing Organization Name and Address I JQ. Proiect/Tjsk/Work Unit No.
, 11. Contract(C) or Grant(G) No.
i
JCO
! (G) '
12. Sponsoring Organization Nam* and Address i 13. Type of Report & Period Covered
U.S. Environmental Protection Agency j
4:01 M Street, S.W. ' • J 300/000
'Washington, D.C. 20460 f-^;
IS. Supplementary Notes
16. Abstract (Limit: 200 words)
The six-acre U.S. Aviex site is located in the City of Niles, Howard Township, Cass
County, Michigan. The site lies in a residental neighborhood with single family homes
100 feet to the south, east, and north. Because there are no storm or sanitary sewers
nearby, surface runoff from the site and surrounding areas flows toward Borne-Huntly
Drain, a tributary of St. Joseph River, and ultimately Lake Michigan. U.S. Aviex
produced non-lubricating automotive fluids from the early 1960s until 1973. During
operations at the plant, chlorinated hydrocarbons, including trichloroethane (TCA), were
leased into the vadose zone south of the process room. The subsurface soil still
tatains significant quantities of TCA, TCE, and PCE. In July 1972, an underground
pipeline containing diethyl ether was broken during excavation near the west wall of the
packaging room. Over the next several years, diethyl ether contamination was identified
in downgradient residential wells southwest of the plant, approximately 0.5 mile away.
U.S. Aviex installed six monitoring wells on the site beginning in 1972 and also
provided alternate water supplies to homes with contaminated wells. In November 1973, a
fire occurred on the site, and the large volumes of water used to extinguish the fire
flushed unknown amounts of chemicals contained in barrels and tanks into the soil.
Following the fire, chlorinated hydrocarbons were detected in domestic wells. Based on
(See Attached Sheet)
17RlceoT<3ntoAf "b'e'c i's f
U.S. Aviex, MI
First Remedial Action - Final
Contaminated Media: gw, soil
Key Contaminants: VOCs (benzene, TCA, TCE, toluene, xylenes)
b. Identifiers/Open-Ended Terms
e. COSATI Field/Group
•liability Statement
19. Security Class (This Report)
None
20. Security Class (This Page)
None
21. No. of Pages
53
22. Price
(See ANSI-Z39.18) See Instructions on Reverse OPTIONAL FORM 272 (4-771
(Formerly NTIS-35)
Department of Commerce
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- U..-W4JH. - - iL
M KC.J"vJK
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EPA/ROD/R05-88/073
U.S. Aviex, MI
irst Remedial Action - Final
f
6. ABSTRACT (continued)
data developed during a ground water investigation in 1982, a purge and treatment system
using air stripping and discharge to surface water was designed and installed to contain
the contamination. Contaminated ground water, however, is currently flowing offsite to
the southwest into residential areas. The primary contaminants of concern affecting
soil and ground water are VOCs including benzene, PCE, TCA, TCE, toluene, and xylenes.
The selected remedial action.fbr this site includes: soil flushing of approximately
11,500 yd-3 of contaminated onsi^e soil; and collection of onsite and offsite ground
water and fluids from the soil flushing process with treatment onsite by air stripping,
and discharge to surface water. The estimated present worth cost for this remedial
action in $3,024,000.
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RECORD OF EHUSICN
J3CTCD REMEDIAL ALTB^KITVE
Site Name and Location
U.S. Aviex
Niles, Michigan
Scatement of Basis and Purpose
This decision document presents the selected remedial action for the
.U.S. Aviex Site in Niles, Michigan, developed in accordance with the
Comprehensive Environmental Response, Compensation and Liability Act of
1980, 42 U.S.C. (9601 et seq. , (OECLA) as amended by the Superfund
Amendments and Reauthorization Act of 1986 (SARA), and, to the extent
practicable, the National Contingency Plan (40 CFR Part 300).
This decision is based on the administrative record for the U.S. Aviex
Site. The attached index identifies the items which comprise the
administrative record upon which the selection of the remedial action is
based.
The State of Michigan has concurred on the selected remedy. A letter
of concurrence is attached.
Description of the Selected Remedy
The selected remedy treats the on-site soil contaminated with volatile
organic compounds (\KXs) by flushing. Groundwater, both on-site and off-
site, contaminated by VXs and fluids from the soil flushing alternative
are collected and treated on-site by air stripping. A public water supply
has been provided to the affected area under a separate action.
Declaration
The selected remedy satisfies the requirements of Section 121(a) of
CEPCLA as amended by SARA. The selected remedy is protective of human
health and the environment, attains Federal and State requirements that are
applicable or relevant and appropriate to this.- remedial action and is cost-
effective. This remedy satisfies the statutory preference for remedies
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-2-
that employ treatment, that reduce toxicity, mobility or volume as a
principal element and utilize permanent solutions and alternative treatment
technologies to the maximum extent practicable. The soil flushing
alternative will be reviewed after five years of operation to ensure that
human health and the environment are being protected by the remedial
action.
7
Date L* valdas V. Mamkus
Regional administrator
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SLMftRY Of REMEDIAL ALmfcPOTVE SELBCTICN
U.S. AVTEX SITE
NTLES, MICHIGAN
August 9, 1988
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TPELE, OF OCNUNTS
Page No.
I. Site Location and Description 1
II. Site Background 2
A. Site History and Enforcement Activity 2
B. Current Site Status 3
C. Public Health and Environmental Impact 5
III. Comnunity Relations History 7
IV. Scope of Response Action 7
A. Selection of Purge Well Locations 8
B. Estimation of Initial Treatment Concentrations 9
C. Groundwater Remediation Goals '. 10
V. Screening of Alternatives 12
VI. Description of Alternatives 14
VII. Summary of the Comparative Analysis of Alternatives 20
VIII. The Selected Remedy ._ 25
IX. Statutory Determinations 26
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Of REMEDIAL ALTEJ&WnVE SELECTION
U.S. AVTEX SITE
Niles, Michigan
I. Site Location and Description
The U.S. Aviex Site is located at 1056 Huntly Road, City of Niles,
Howard Township, Cass County, Michigan in a residential neighborhood made
up of essentially single family hones. The nearest hones are within 100
feet south, east and north of the approximately six acre property. Minor
agricultural and horticultural activities take place in the general
vicinity of the site. There are three schools approximately 2.0 miles
west of the U.S. Aviex site. Two schools are located about 1.5 miles
northwest of the site. There are no storm or sanitary sewers nearby.
Surface runoff from the U.S. Aviex site and nearby areas flows toward the
Bame-Huntly drain and subsequently into Brandywine Creek, which begins
about 0.5 mile east of the site. Brandywine Creek flows into the St.
Joseph River in Niles. The St. Joseph River flows into Lake Michigan at
St. Joseph, Michigan. See Figure 1 for a map of the U.S. Aviex plant
site.
Baron Lake, a seepage lake with no surface inlets or outlets, is
about 0.5 miles northeast of the site. The lake has a surface area of 199
acres and a maximum depth of 28 feet. There is a small wetlands west of
the lake.
Site topography is generally level, with occasional low rises and
gentle depressions. Very generally, the surface elevation rises 15-18
feet per mile from east to west in the vicinity of the site.
The site is located in an area of glacial deposits. Two broad types
of deposits occur: glacial outwash and ice contact outwash. Typically
these deposits are stratified and exhibit varying degrees of sorting
between individual units, with considerable lateral variation. The upper
unit of sand and gravel contains discontinuous clay layers and lenses;
within this unit the vadose zone is 15 to 45 feet thick.
The water table aquifer is defined by a discontinuous sandy clay
layer. The saturated thicJmess of the aquifer is 70 to 90 feet near the
site, increasing to 100 feet in the western portion of the study area.
Groundwater flow is southwest to west from the site becoming westerly
approximately 0.5 miles downgradient. Transmissivity in the area is
between 225,000 gal/day/ft and 31,000 gal/day/ft with a flow velocity of
approximately 0.5 ft/day. Limited data indicates the presence of an
artesian aquifer below the sandy clay layer with a flow pattern similar to
the upper aquifer. The replacement residential wells are placed in this
aquifer.
While the plant is no longer in operation, some buildings on the site
are used for storage of non-production related materials. The original
structures are shown in Figure 2. The structures presently in place
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> •0*6^ rV -
l\i^.« b5Jl_If>-^^'
ft .. ...-.^^^
i;«J* • . 1-—s.
\ '^
I * j -
• • • -^ • - • •
Adapted from EDI (1987b)
FIGURE 1 LOCATION OF THE U.S. AVIEX PLANT SITE
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Gravel Parking
14 Gravel Drive
Tank Farm
Non - Awocol Filling Room
EatlWarthout* OfflCM
I-Bay
Truck Dock
OBD
1 -JdllM
rm.Knji.n
Adapted from EDI (1987b)
FIGURE 2 DETAIL OF U«>. AVI EX PLANT SITE
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include the west warehouse, the concrete slabs from the middle and east
warehouses, the offices, batch room, aerosol filling room, packaging room,
truck docks, and the concrete, bituminous, lawn, and most of the gravel
surfaces. The tank farm and part of the gravel parking area now consist
of uneven ground and a bermed impoundment used for temporary storage of
non-hazardous groundwater produced during an aquifer test performed on the
site.
II. Site Background
A. Site History and Enforcement Activity
U.S. Aviex produced non-lubricating automotive fluids at the Huntly
Road Plant from the early 1960s until late 1978. Activities at the plant
included the repackaging of bulk products and the formulation of new
products from bulk ingredients.
Sometime during the operation of the plant in the 1960s or 1970s,
chlorinated hydrocarbons, including Trichloroethane (TCA), were apparently
released into the vadose zone beneath the bituminous pavement south of the
process rooms. These soils still contain significant quantities of TCA,
Trichloroethylene (TCE), Perchloroethylene (PCE) and dichloro-compounds.
In July 1972, an underground pipeline containing diethyl ether was
broken during excavation on the southeast side of the plant site near the
west wall of the packaging room. Within a few months, diethyl ether (DEE)
was detected in nearby residential wells on Lilac Street. Over the next
several years, diethyl ether contamination was identified in downgradient
residential wells southwest of the plant as far as Blanchard Street and
Almaugus Drive, approximately one half mile away. Under an agreement with
the Michigan Department of Public Health (MDPH), U.S. Aviex installed six
monitoring wells on the site beginning in 1972 and also began supplying
bottled water to homes with contaminated wells. In addition, U.S. Aviex
installed new wells in a lower, uncontaminated aquifer for selected
residences.
On November 28, 1978 a fire occurred on the site. The large volumes
of water used to extinguish the fire washed unknown amounts of chemicals,
released from barrels and tanks in the process buildings, onto unpaved
areas. Following the fire, chlorinated hydrocarbons were detected in
domestic wells as far west as Bame Street.
Early in 1982, the State of Michigan initiated legal action against
U.S. Aviex and reached an agreement for a groundwater investigation of the
site. On the basis of data developed during this investigation, an on-
site groundwater purge and treatment system was designed and installed to
contain the contamination outlined in the groundwater investigation. The
system pumps up to a combined 200 gal/min through two purge wells from the
contaminated upper portion of the aquifer. The water is then treated by
air stripping and discharged to the surface water in compliance with a
NPDES permit issued by the State of Michigan.
-------
Tne U.S. Environmental Protection Agency (USEPA) initially became
involved in the U.S. Aviex Site in 1984 as a result of its being placed on
the Superfund National Priorities List. In 1985, U.S. Aviex agreed to
fund a Remedial Investigation/ Feasibility Study (RI/FS) under an
Administrative Order on Consent. The goal of the RI/FS was to determine
the nature and extent of the threat to the public health or welfare or the
environment caused by contamination from the U.S. Aviex plant site and to
evaluate alternatives to establish the appropriate remedial actions to
prevent or mitigate the migration or release of contamination from the
site.
In 1986, U.S. Aviex filed Chapter 11 bankruptcy with the Bankruptcy
Court for the Eastern District of Michigan. Funds had been previously set
aside by U.S. Aviex to pay for the RI/FS so that the bankruptcy action did
not stop the ongoing RI/FS at the site. Over the past two years, the
federal government has been actively negotiating with U.S. Aviex and its
creditors to reach an agreement to be approved and filed with the
Bankruptcy Court, allowing for reimbursement of USEPA »s costs of
overseeing the RI/FS and sane allowance for the anticipated clean-up
costs.
Pursuant to Section 121 of SARA, a responsible party is ordinarily
afforded the opportunity to negotiate an agreement with USEPA regarding
the design and implementation of the selected remedial action. Due to the
bankruptcy status of U.S. Aviex, however, the USEPA determined that
negotiations for the funding would prove futile since the company does not
possess available funds to pay for the clean-up.
Also, in 1985, under Michigan Act 307, the State of Michigan took
steps to provide a public water supply and distribution system to the
affected area. TJie system distributes water from the City of Niles public
water supply to an estimated 220 homes in the area. Ine system is now
complete and area residences have been connected to it.
B. Current Site Status
Chemicals originating in the soil at the U.S. Aviex plant site have
contaminated groundwater beneath the site, formed a plume with the
groundwater in the upper aquifer and are flowing off-site in a
southwesterly direction. Tnis plume is bounded on the north by a line
from the site northwest to near the intersection of Janellen and Carberry
Road, on the southeast by an irregular line extending from the site in a
southwestern direction, and on the west by Carberry Road. Ine compounds
within the plume have been identified as chlorinated hydrocarbons, diethyl
ether and other volatile organic compounds in concentrations in the range
of 0.001 mg/L to 5.6 mg/L.
Chemicals in the plume, if unabated, will continue to flow southwest
down the hydraulic gradient into farther reaches of the neighborhood. Tne
estimated speed of groundwater movement down the centerline of the plume
in the study area is approximately 0.5 feet per day. Table 1 shows
concentrations of the indicator compounds at three down-gradient exposure
-------
points as determined by modeling.
Significant quantities of chlorinated hydrocarbons remain in the
vadose zone beneath the entrance driveway to a depth of twenty feet near
.the southeast process buildings. There are about 10,000 cubic yards of
contaminated soils in this area and about 1,500 cubic yards of
contaminated soil in the truck dock near the west warehouse.
Concentrations of volatile organics in these soils range from 0.01 mg/kg
to 13.0 mg/kg.
In addition, a source of DEE may ranain on the site in the north
central area east of the former tank farm (see Figure 2). Additional
investigation during the Remedial Design (RD) stage will be necessary to
quantify this source and further define the on-site and off-site
contamination of the soil and groundwater.
Operation of the purge wells and stripping tower on the site
continues as provided for in the 1982 agreanent between the State of
Michigan and U.S. Aviex. The locations and spheres of influence of the
purge wells during typical operation in Septanber 1986 is shown in Figure
3. Containment is essentially complete for the most highly contaminated
zone beneath the southeast entrance driveway area as this zone of
contamination is within the sphere of influence of the purge wells.
However, containment of the contaminants at the west boundary of the
property is not complete because the extent of contamination west of the
property boundary extends beyond the sphere of influence.
The RI identified twenty-five (25) volatile and said-volatile
organic chanical compounds in the on-site subsurface soils or the on-site
and/or off-site groundwater. Table 2 summarizes these contaminants in
each medium.
Of these twenty-five (25) volatile and sard-volatile organic chanical
compounds, ten (10) were selected as indicator compounds to meet the
objectives of the RI. Each indicator compound was selected because it
meets one or more of the following criteria:
* It is a known or suspected carcinogen.
* It is a compound for which the USEFA has established drinking
water Maximum Concentration Levels Goals (MCLGs) nr proposed
Maximum Concentration Levels (MZLs) or proposed MCLGs.
* It has a Safe Drinking Water Act Water Quality Criteria
value (for drinking water only, no risk consumption).
* It is a compound identified at more than one sample location.
* It is a compound which occurs in extranely high concentrations.
The indicator chanical compounds selected for detailed study are:
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Trans-l,2-dicHloroetnylene (Trans-1,2-DCE)
Benzene Trichlorofluoronetnane (TCFM)
1,2-Dichloroethane (1.,2-DCA) .Dichlorofluorcmethane (DCFM)
1,1-Dichloroethylene (1,1-DCE) Diethyl ether (DEE)
1,1,1-Triciiloroethane (1,.1,1-TCA) Perchloroethylene (PCE)
Tricnloroethylene (TCE)
C. Public Health and Environmental Impact
No land uses other than the ones currently existing at exposure
points are assumed. The U.S. Aviex plant is inactive but manufacturing
facilities remain on-site and are presently used for storage only. There
is no indication that anyone has been present on the site for an entire
year. The land surrounding the site is a developed residential area and
is likely to remain as such.
Potential exposure pathways based on estimates of exposure point
concentrations in on-site and off-site ground water, in on-site air, and
in on-site soils are ranked in approximate order of importance:
* Ingestion and associated contact with contaminated groundwater
* Direct contact with on-site soils
* Inhalation of airborne contaminants from soil volatilization
and stark gas
* Inhalation of volatiles from ground water
* Ingestion of and contact with surface water
* Ingestion of contaminated fish and crops
In the absence of rigorous quantitative risk assessments, risk is
assessed in two ways in accordance with the guidelines contained in the
Super fund Public Health Evaluation Manual (USEPA 1986). First, the
exposure point concentrations in various media are compared to the
Applicable or Relevant and Appropriate Requirements (ARARs). The
resultant ratio (exposure level/acceptable level) is not a quantitative
measure of the incidence or severity of effects, but a numerical indicator
of the transition between acceptable and unacceptable exposure levels.
Any ratio greater than 1.0 indicates an unacceptable exposure level.
Second, chronic and subchronic chemical intakes are calculated from
exposure point concentrations and standard human intake factors. Non-
carcinogenic risks are assessed by calculating the ratio of human intake
to the route specific Acceptable Intake for Subchronic Exposure (AIS) and
the Acceptable Intake for Chronic Exposure (AIC) values and the ratio is
summed to provide a total hazard index for that exposure route. The
assumption that the adverse effect is proportional to this sum is
consistent with USEPA's risk assessment guidelines for chemical mixtures,
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lndlc.il or riirralc.il
M"i|i-l 1: Inst.inraneiiiis
Uon/riio
I , I dl'flilororlli.ino
I ,?-l»i. liloro'Mli.inc
1,1 -Olclilorpethylone
Hl.yl cil.or . ,
IVtrai-hliiroetliylrnc
1,1,1-Trlcliloioetbaue
T-- i ..I. I AB..A.*.* I... I ^...» * *• '
Trli'hloroethy I cue
Trlchlorof liioromi'th.ine
(e)
2: Cnntliiuous Release
1 ,l*l)lchlorr>elli.ini>
1 ,2-IXclilornetliane
I . I -Olchloroeiliylenc
F.tliyl ether /e»
Tor rachloroethylrne
I ,1 ,1 -Trlchloioctbaue
Trlclilnroethylemr . .
Trlchlorof luorowplli.ine
I.F. J MODELED GROUND-WATER CONCENTRATIONS AT THREE EXPOSURE POINTS
Alm/uiguit St. (0.33 ill le.i)
lirst ( )
Estimate,1*'
mg/L '
ase
0.00052
O.O1)
0.113
0.012
1.07
0.004
0.309
0.013
O.OH9
0.004
1.46
2.58
0.747
6.41
0.039 i
2.76
0.171
0.773
llppet/h»
Bound,
ng/L
0.001
0.236
0.674
0.038
4.210
0.009
0.680*
0.029
0.195
0.007
2.95
3.5
0.497
10
0.064
4.55
0.2
1.27
[hit nFlou, »
of I'ula-e/0'
yeara
2-
7-
4-57
10-
4-
2-
2-
2-
2-
2-
8-
5-
11-
5-
2-
2-
2-
2-
Carlterry Pd. (1 mile)
llest
Estimate,
atg/L
4.70xlO~5
0.00094
O.OJ6 ,
4.7xlO"5
0.168
0.00037
0.028
0.0012
0.008
0.00042
0.00553
0.803
0.00023
0.563
0.00369
0.26
0.011
0.073
Upper
Round,
"B/l
0.00013
0.011
0.12
0.00068
0.733
0.0011
0.082
0.004
0.024
0.002
0.078
3.31
0.0043
4.33
0.018
1.25
0.055
0.35
lhjr.it (on
of Pulse,
years
15-
44-
25-
55-
28-
15-
15-
15-
15-
17-
43-
25-
53-
29-
17-
17-
17-
17-
Huiilclp.il W-lls (7
best Hppor
Estimate, Buiind,
ng/L mp/l.
2.60xlO"B 3.50xlO~7
2*'ol Arrlvrd-
3.50x10 0. 00(111
-Not Arrlvrd-
:Not Arrivrd-
2.10x10, 2.H*IO~b
1.60x10, 0.00071
6. 80x10"' 9.0x10"^
4.50x10"" 6.0x10°
9.38xlo"8 1.44xlo"6
iNot Arrlved-
1.48x10*' 0.00051
-Not Arrlved-
iNot Arrlvetjt
8.20x10"' 1.76x10 '
5.86x10° 0.0009
7.58x10", 3.97x10"'
1.64x10"' 0.00025
V
mllrs)
l/iir.if I'-u
of |>u ISP,
_Xc;lr';
55-
65-
55-
55-
55-
55-
53-
63-
53-
53-
53-
53-
(.1) Soveiity-ycar wean.
(It) H.i x I mum concentration In 70 years. .
(r) Tit* tl.ite of the st.irt and end of the arrival concentration* >10
coul Inurs p.i.tt 70 yrjr*.
(d) Compounds r<-|p.isc(4 during spllH, but not after purge wella operate. •
(i>) C.i I fit I.it I'd (I'. Inj' s.im<» pi Mint" tr
-------
74543
^623
Legend
\
Purgo Woll
Moniloilng Well
Groundwaler Conlbur
70 gpm rialo of Pumping
on or hoar lha
Dalo Shown
744.76 Waiar Tablo Elovalloos
Observation Dnlo:Scpicmbcr 23. 1906
EastCompanlon Woll
- r ni
A Science
figuro J
Purge Well Capture Zone
US. Avlox
-------
TABLE 2. SUMMARY OF ANALYTICAL RESULTS FOR CHEMICAL COMPOUNDS
On-SHe Wells
Off-Site Wells
Chemical Compounds
Acetone
Benzene
Carbon tetrachlorlde
Chloroethane
Chloroform
Methyl cyclohexane
Dlchlorodl fl uoromethane
1,1-Dichloroethane
1,2-01chloroethane
1,1-Dlchloroethylene
Trans-1,2-dlchloroethylene
01 chi orofl uoromethane
Dimethyl disulfide
Ethyl benzene
Ethyl ether
Isopropanol
Methylene chloride
Tetrachloroethylene
Toluene
1,1,1-Trlchloroethane
Trlchloroethylene
Trlchlorofl uoromethane
2,2,4-Trlmethyl pentane
2,2,4-Trlmethyl pentane
Xylene
Range
(•g/L)
0-0.190
0-0.029
NO
0-0.050
0-0.001
0-0.011
0-1.000
0-3.100
0-1.600
0-5.200
0-0.570
-
0-0.003
0-1.900
0-5.700
ND
0-0.002
0-31.00
0-1.600
0-200.00
0-0.880
0-27.000
0-0.005
-
0-1.600
Mean
(•g/L)
0.011
0.003
-
0.004
4.5x10-5
0.003
0.143
0.366
0.089
0.278
0.059
-
0.001
0.146
0.661
.
9.1x10-5
1.042
0.073
15.026
0.135
1.756
0.001
-
0.080
Range
2/20
9/32
0/22
3/22
1/22
1/4
2/7
18/32
7/32
10/32
11/32
0
1/4
7.29
15/28
0/20
1/22
11/32
1/22
13/32
12/29
12/32
1/4
0
1/20
0-0.33
0-0.005
ND
0-0.013
ND
.
0-0.003
0-1.700
0-1.700
0-0.330
0-0.110
0-0.070
-
0-0.090
0-4.800
ND
0-0.004
0-0.040
0-0.004
0-3.00
0-0.130
0-0.860
0-0.008
0-0.002
0-0.010
Mean
{mg/L)
1.9x10-4
3.9x10-5
-
7.3x10-5
_
5.0x10-4
0.025
0.024
0.004
1.4xlO-3
0.019
-
0.001
0.036
_
3.4x10-5
4.lxlO-4
2.8x10-5
0.026
0-0.001
0-0.009
0-0.002
0-0.001
1.1x10-4
Nj/N2
1/171
3/178
0/178
1/178
0/178
0/0
1/5
12/178
9/178
4/178
4/178
2/4
0/0
6/171
8/158
0/178
2/178
4/178
2/178
18/1 7ft
4/178
4/168
1/4
1/4
2/178
Range
(mg/kg)
(2)
.
0-1.230
_
_
_
•
0-0.120
_
0-0.045
_
_
0-0.170
—
—
_
0-10.200
0-0.005
0-23.800
0-1.650
0-0.160
«.
—
0-0.010
Soil
Mean
(nig/kg)
_
0.041
_
_
_
_
0.012
_
0.005
_
—
0. OUH
_
_
0.761
1.7xlO-4
1.631
0.095
0.014
_
_
3.6x10-4
«,H2
_
I/JO
_
.
_
r,/^«)
_
'j/?'J
„
—
_
f)/:'(i
.
_
\i\l\i
I/,11)
i i/ii
6/.II
7/29
..
_
\I2\\
(1) Nj = number of samples In which contaminant was detected;
analyzed.
(2) -, Compound not analyzed for.
(3) ND = Not detected.
number of samples
-------
Three of the exposure routes can be quantified. These routes are (1)
possible ingest ion of contaminated groundwater, (2) direct contact with
contaminated on-site soils, and (3) inhalation of volatile emissions from
site soils and stack gases.
1. Ingestion Route for potential ground-water and surface-water
exposure via drinking water: The most appropriate ccrrparison values are
the MZLs of the Safe Drinking Water Act. Since these Federal drinking
water •standards and criteria are based on lifetime exposures, it is
appropriate to use a ratio of long-term water concentration to the
standard. Ratios were calculated in two ground-water transport models
(instantaneous -ind continuous release) at 0.33, 1.0 and 2.0 miles from the
site. On-site ratios are comparable to those calculated at 0.33 miles.
Upper-bound estimates are calculated based on the maxiirun concentration
levels experienced by the three locations in seventy (70) years.
Incremental cancer risks exceeding 10~6 indicate potential endangerment
(USEFA 1986). Carcinogenic risks from ground-water ingestion exceed 10~6
at Almaugus Street (0.33 miles) and Carberry St. (1.0 miles), assuming
either continuous or instantaneous release. In the worst case (continuous
release) scenario, 1,2-DCA, 1,1-DCE, FCE, ICE and benzene all exceed the
critical risk 0.33 miles from the site, and all but benzene and 1,1-DCE
exceed this level 1.0 miles from the site. At the municipal wells 2.0
miles from the site, no contaminants of concern are at unacceptable levels
now or at the end of the seventy-year period.
Hazard indices for individual indicator chemicals are sumned and
calculated to provide the total hazard index for the ground-water
ingestion route. The noncarcinogenic chronic hazard index exceeds 1.0
only for the worst case scenario 0.33 miles from the site. Two indicator
chemical compounds, 1,1-DCE and 1,1-DCA, contribute most heavily to the
noncarcinogenic risk index. The chronic hazard index does not exceed 1.0
in seventy years at the more distant locations; the subchronic index does
not exceed 1.0 at any location. These conclusions would be the same for
resident children even though they have a daily intake about four times
that of adults.
2. Soil Contact Route: There are no unacceptable risks for the soil
contact route. Since there are no ARARs with which to conpare soil
contact risk, a comparison was made between the chronic acceptable oral
intake values and calculated chemical intakes at the site to determine the
potential endangerment to adults by direct contact with on-site soils.
Miltiplying chronic daily intakes in mgAg/day by the oral or
inhalation cancer potency factor for the appropriate contaminant, yields
the incremental lifetime cancer risk associated with ingestion or
inhalation of that contaminant (USEEA 1986). Individual contaminant risks
are surnned so that the total risk due to carcinogen ingestion or
inhalation for a particular route are obtained.
3. Inhalation Route: The potential endangerment from the inhalation
-------
route is low. since there are no ARARs with which to compare ambient air
concentrations resulting from soil volatilization and stack gas emissions
daily intakes are calculated using the USEPA's risk assessment guidelines
for chemical mixtures (USEPA 1986). Neither subchronic or chronic total
noncarcinogenic hazard indices approach 1.0 for either soil volatiles or
stack gas. Soil volatiles contribute more contaminants to the air than
stack gases but the numbers are very small. Adding the two totals to
reflect exposure to both sources has little effect on the index as the
totals never exceed 0.05 for best estimates or 0.6 for upper-bound
estimates.
Cancer risks from purge well stack emissions are low (2.63 x 10~8).
The highest estimate of incremental cancer risk from inhalation of soil
volatiles is 4.76 x 10~7. Total upper-bound risk, calculated using the
highest measured soil concentrations, is 4.72 x 10~6. 1,1-DCE is the
major contributor to this risk. The air inhalation route, therefore,
presents a low risk of potential endangerment. The highest cancer risk,
estimated from mean soil concentrations of cancer risk from dermal contact
with soil, is 1.9 x 10~8.
III. Community Relations History
Public participation requirements set out by Sections 113 and 117 of
CEECLA, as amended, were satisfied during the remedial action process and
include the following: Potentially affected persons and the public where
notified of the remedial action through two notices published in the local
Niles community newspaper; interested persons on the Agency's mailing list
received direct mailings; information repositories for public review were
established at the Howard Township Hall and the Niles Community Library;
the U.S. Aviex Administrative Record was made available to the public and
is housed at the Niles Community Library, and Fact Sheets were distributed
at public meetings. Two public meetings were held ori June 15 and July 12,
1988 to discuss the Proposed Plan and the RI/FS, and accept comments.
A twenty-one (21) day public cocment period for the Proposed Plan
commenced on June 6 and ended on June 26, 1988. As a result of public
interest in the U.S. Aviex remedial action, the public comment period was
extended through July 18, 1988. A Responsiveness Summary detailing the
Agency's response to significant comments submitted during the Garment
period, is attached to the RCD.
IV. Scope of Response Action
At the U.S. Aviex site there is a potential public health hazard from
exposure to contaminated groundwater. The public health risk results from
the possibility of persons in the effected area consuming contaminated
groundwater and the long-term potential impact on the City of Niles
municipal water supply wells. The 'purpose of the overall remedial
objectives are to provide:
* On-site control of the source of contamination by minimizing
leachate production of contaminated groundwater under the site in
-------
to off-site areas.
* Off-site management of plume migration. Purging and treating
groundwater within the 10~6 and/or noncarcenogenic threshold value
plume to meet Federal or State drinking water quality standards and
criteria will reduce the potential for human exposure to
contaminants and reduce the impact on groundwater resources by
minimizing migration of off-site contaminants.
To evaluate the remedial action alternatives for the off-site control
of groundwater, analytical modeling simulation of the aquifer along with
the addition of hypothetical purge wells to capture the contaminant
plumes, was done.
Permeability data, developed during the modeling of the aquifer in
the RI, was reviewed and a representative value used, along with the
typical aquifer thickness, to obtain a transmissivity (T) value of 90,000
gal/day. A storage factor(s) of 0.13, used in RI modeling, and an
alternate value of 0.2 were employed along with the T value in an
analytical well-field model, developed by EDI, which is based on Theis and
Jacobs modified nonequilibrium equation. The relative position of the
computer generated capture plumes was nearly the same under the
alternative storage factor assumptions.
Other assumptions included -in the model are a pumping time period of
two weeks (T+14 days) and recharge due to precipitation at twelve inches
per year. Several trial runs resulted in alternative scenarios for
groundwater capture on-site and off-site using up to five wells, producing
in the range of 60 to 180 gal/tain.
The remainder of this section discusses the factors considered in the
selection of purge well locations, the procedure used to estimate the
initial treatment concentrations and the remediation goals for the ground-
water and effluent.
A. Selection of Purge Well Locations
The purge wells were located in the areas best suited for evaluating
the groundwater capture alternatives and to recover DEE from the semi-
isolated shallow groundwater zone area of Purge well 82-3 (See Figure 4.)
Purge well 3A (See Figure 4) will be installed to operate as a
supplemental well to the pair of purge wells currently on site. This well
will effect continued cleanup of groundwater beneath the site,
intercepting chemicals leaching from the vadose zone in the existing
entrance driveway area, capturing contaminants at and beyond the southwest
corner of the site. The total groundwater flow rate will be approximately
250 gal/min. The groundwater capture zone, for this alternative is assumed
to be just beyond the site boundaries.
Four purge wells are located in the contaminant plume of
toxi co logical and risk-assigned chemicals up to and including
-------
concentrations at the 10 6 level and corresponding toxicological threshold
values. The position of the estimated area of groundwater capture and
approximate well locations are shown in Figure 5. Purge well IB. the
existing east purge well, is designed to operate at 60 gal/min. and
contain the source of contaminants in the entrance driveway area. Purge
well 2B. to be located near the intersection of Same Avenue and Lilac
Street, is in the higher concentration zone of the dichlorinated volatile
organic compounds (VDCs). The well is designed to operate at 120 gal/fttin.
Purge well 3B is located a little beyond the downgradient lijnit of the 10"
6 risk area on Blanchard Street and is intended to produce at 180 gal/roin,
Purge well 4B is located on the north/south leg of Blanchard Street in the
higher concentration zone of contamination of the \/DCs. and is intended to
operate at 120 gal/min.
The total pumpage from the four purge wells is 480 gal/min. When
combined with the shallow ether-capture wells on site, the estimated total
flow to treatment will be 500 gal/min.
Five purge wells are sited to capture primary groundwater
contamination. The position of the estimated area of groundwater capture
and approximate well locations are shown in Figure 6. Wells 1C and 2£
correspond to Wells IB and 2B, respectively, and will fulfill the same
functions as in the 10~6 risk-related alternative. Well 3C is sited
approximately 600 feet northwest of its 3j3 counterpart and off the center
of the plume. Well 4C is sited approximately 600 feet northwest of the
Yankee Street homes (2379 and 2383) that showed the 1,1,1-TCA. Well 5C is
located approximately 350 feet north of Almagus Drive and Lilac Avenue to
intercept the low levels of PCE.
Wells 3C and 4£ have been shifted to the north of the plume center
to effect a continuous groundwater capture zone with Well 5C and maintain
an area of influence that extends a sufficient southward distance to
capture all the primary plume.
B. Estimation of Initial Treatment Concentration
Treatment influent and effluent data from the existing operational
purge and treat system were used to estimate initial concentrations under
the groundwater capture alternatives. Concentrations insignificant for
developing treatment alternatives were not considered and included very
low levels of chlorinated organics and DEE.
The estimation procedure consisted of:
* Assigning concentrations, by compound, to each proposed purge
well based on the local groundwater quality data collected in
1986.
* Weighing the combined influent concentrations to the proposed
purge wells according to individual purge well flows.
* Reducing the weighted results by 50%.
-------
NW
i. -10 A
A
West Companion Well A
2A
— CDI Enrjlnccrlng A Science
0
I
Ramp
HO
Legend
9 Shallow Exploration Wells •» Ul Pha;.o
O Shallow i:>|»loralion Wulls - 2nd PJtas-i
Existing Monitor ing Well
,' / DEE Capluro Area
1A
liani Companion Woll
A-:O
( IQIIIO 4
On-Sllc Purno Well
and Dm Cnplurc Zone
US. Avic-x *
-------
t:
» v..
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! pt,u to o" [Iu jj
•" 6»'.LZ'^^
£"%. ^-~"~m •
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— =^r!" =-=-.-— S^: •
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-CO) Cngln««r
-------
\
\\
\
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\
-SOI Cngltmilny » Science <
• Puig«wt«
C • Cjpllll* Innt
•* _ -*•
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Puig* Wtll iaciiiohi *rid ittilniii
US *v.,i
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-------
10
Table 3 includes the :data involved in the compound concentration
estimates.
C. Groundwater Remediation Goals and Minimum Treated Effluent
Discharge Goals
The groundwater cleanup strategy for the U.S. Aviex site is to
install and operate purge wells in the plume that will collect and treat
oil-site and off-site contaminated groundwater found within the U.S. Aviex
related 10~6 risk plume and in the primary plume, out to its projected
limits, (see Figure 7) to comply with existing drinking water standards or
EPA or MCNR water quality criteria values for human health (see Figure 8).
Table 4 lists the clean-up goals for the chemical compounds of concern.
GROJNDWATER CLEAN-UP GCKLS
CdiiLOund
Concentration
(mg/1)
Benzene
EthyUbenzene
Toluene
Xylene
Chloroform
1,2-DCA
1,1-DCE
TCE
PCE
Trans-l,2-DCE
1,1,1-TCA
DEE
TCFM
DCFM
0.005
0.680
2.0
0.440
0.002
0.005
0.007
0.005
0.00088
0.70
0,200
0.043
32.0
3.0
Risk level
4 x 10~6
1 x 10-6
1 X 10~5
1 X 10~4
2 X 10~6
1 X 10~6
Basis
MIL
Proposed MZLG
Proposed MZLG
Proposed MZLG
Water Quality
Criteria for
Human Health
MZL
MZL
MZL
Water Quality
Criteria for
Human Health
Proposed MZL
MZL
MDNR Rule 57-HLSC*
MCNR Rule 57-HLSC*
MDNR Rule 57-HLSC*
* Concentrations proposed but never adopted due to insufficient data.
The proposed groundwater cleanup alternatives(s) will be in operation
until the water quality within the plume is remediated to a level that
equals or exceed the individual compound concentrations listed in Table 4.
In the process of achieving groundwater ..cleanup goals, the purged ground-
water would be treated to meet minimum concentrations for the various
chemicals of concern prior to discharge, based on either NPDES permit
limits or POIW industrial pretreatment standards. The minimum effluent
goals for this site are presented in Table 5. City of Niles POIW
pretreatment standards are shown in Table 6.
-------
Purge Nell Compound Concentration Estimation Data/Summary
FlOWS
A Nells In B Wells In
Purge Concentration Alt C-1/C-2
Nell Compound (mg/1 ) Data Source Alt B-1/B-2 10 Risk Plume
1 1,1,1-TCA
1,2-OCA
1,1-DCA
1,1-OCE
TCFH
2(B,C) DEE
,1.1-TCA
,2-DCA
,1-DCA
,1-OCE
CFM
38 ,1,1-TCA
,2-DCA
DCFM
3C B-T-X
(Beniene,
toluene,
xylene)
«B DEE
1,1,1-TCA
1,2-DCA
«C 1,1,1-ICA
5C PCE
0.8
0.012
0.0%
0.015
0.09
5.6
2.0
I.S
0.5
O.I
0.09
0.1
0.5
0.00)
0.1
1.0
0.5
2.0
0.01
0.0*
Existing 100 60
Purge Mel It
EiiUtlng
Purge MelU
Existing
Purge Nells
Existing
Purge MelU
dlttlng
Purge MelU
86-3 - 170
Fig. 21 (Ml)
86-3
Fig. 22 (Rl)
Fig. 2* (Rl)
86-2
Fig. 21 (Rl) - 180
Fig. 23 (Rl)
, Fig. 25 (Rl)
M»
Almagut
Fig. 20 (Rl) - 170
Fig. 21 (Rl)
Fig. 23 (Rl)
Fig. 21 (Rl)
Fig. 25 (Rl)
C Nells
Alt C-1/C-2
Primary Plume Remark*
60 Existing combined purge i*e11 Influent
(*/87) H 2 to estimate PM 1 valve
Existing combined purge Nell Influent
(*/»/) ii 2 to estimate PM 1 value
Existing combined purge net! Influent
(W87) x 2 to estimate PM 1 value
Existing combined purge *ell Influent
(*/87) x 2 to estimate PW 1 vaUe
Existing combined purge well Influent
(4/87) x 2 to estimate PM 1 vaUe
120 86-3 well Is the same as on-slte
monitoring well E-40A
"
ISO Mell 3C's location Is north of the
m«ln plume to effect a combined c«p-
ture tone wlthVfell SC. Mall 1C ««y
Intercept B-I-H bated on pre-1986
house well testing by HOPtl.
•
150
120
-------
TABLE 3 (CONT'D)
DONS
A Wells In B Wells In
Purge Concentration *lt C-1/C-2
Well Compound (mg/l) Data Source Alt B-1/B-2 10 ° Risk Plume
3A 1,2-DCA
1.1 -OCA
trans~
1,2-DCE
Beniene
Cluster DEE
•t 82-3
Existing On-»lte
West Purge Well
Total Flows
(gal./mln.)
DEE
1.1.1-TCA
1,2-DCA
1,1-DCA
1,1 -DCE
TCFM
DCFM
PCE
tr.nt-1,2-DCE
B-l-X
1.6
1.1
0.2
0.01
5.7
A Wells
B-1/B-2
O.M
0.3
0.)
0.22
0.006
0.0)3
-
-
0.037
-
Table 1 (Rl) SO
TabU 1 (Rl)
Table 1 (Rl)
TabU 1 (Rl)
Table 1 (Rl) 20 20
100 _^_
270 500
Total Concentrations
B Wells C Wells
C-1/C-2 C-1/C-2
i
1.8 1.3
0.61 0.47
1.02 0.29
0.13 0.10
0.026 0.023
0.032 0.026
0.001
0.008
-
0.024
C Wells
Alt C-1/C-2
Primary Plume Remarks
July 1986 monitoring
E-40A
July 1986 monitoring
E-40A
July 1986 monitoring
E-SOA
July 1986 monitoring
E-40A
20 July 1986 monitoring
_-__
620
A Wells B Wells
B-1/B-2 C-1/C-2
0.21 0.9
0.15 0.31
0.15 0.51
0.11 0.065
0.003 0.013
•
0.017 0.016
0.0005
-
0.018
-
results E-tO*
results E-*0,
results E-*0,
results E-»0,
results 82-3
C Wei It
C-1/C-f
0.65
0.24
0.15
0.05
0.012
0.011
-
0.004
-
0.012
-------
NOTE: H<>kConlou'V«nls
-BCM Enqln»»rlofl * Sctanc* •
loBjrhqtound
1.10" linj«
I • 10 ' IvtlOOOO
i. to ' luiionoor)
1.10 • IMI oooono
M
0 400
S< JltflK t fl
EitlmjIedC
Total HumjiFii-
with MjumumC
o' Cj'cinogen
Oelcctrdin Ciou
US «..
•i'. socialnl
>• rnlrclloiij
t iimpouitil'
.I98i»
-------
-
ac?
10 a
n
a
*^
- f Ol CnglnMtlng 4 »ct.n««
,-
£. '
£?
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•i«
•.->!
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o <^
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+ "1J J
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o too tap nn
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By Compuunri: 1986
Con<(>4ii)i.ill«irti«,ii..ii>i:r><
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-------
11
MINIMUM EFFLUENT GOALS (surface water)
Concentration
Compound (mg/L) - Basis
Benzene 0.051 MCNR Rule 57 - ACV
EthyLbenzene 0.062 MCNR Rule 57 - ACV
Toluene 0.100 MCNR RULE 57 - ACV
Xylene 0.040 MENR Rule 57 - ACV
Chloroform 0.043 MCNR Rule 57 - CRV
1,2-DCA 0.560 MCNR Rule 57 - CRV
1,1-DCE 0.003 MCNR Rule 57 - CRV
TCE 0.094 MCNR Rule 57 - ACV
PCE 0.020 MCNR Rule 57 - CRV
Trans-1,2-DCE 0.090 MCNR Rule 57 -TLSC
1,1,1-TCA 0.120 MCNR Rule 57 - ACV
DEE ' 0.275 Technology Based*
TCFM 0.020 Technology Based*
DCFM 0.020 Technology Based*
AVC - Aquatic Chronic Valve
CRV - Cancer Risk Value
TLSC - Terrestrial Life Cycle Safe Concentration *Based on Air Stripping
Diethyl ether (DEE) at 5-6 mg/L persists in a shallow, thin, saturated
zone of ground water (5-15 feet thick) at depths ranging from 20 to 40
feet in the area of on-site monitoring well 82-3 (See Figure 4). This
saturated zone is underlain with clay. The continued presence of the DEE
is due to the poor hydraulic connection between the DEE zone and the part
of the aquifer in which the existing purge wells are operating.
Four shallow exploration borings and wells are proposed, see Figure 3,
to identify the limits of the TTFT* zone in the first phase of
investigation. The drilling would use hollow-stem auger with split-spoon
sampling and field screening of soils at five foot intervals. Two-inch
galvanized steel casing with three foot stainless steel well points would
be installed, the top of the screen three feet below the water table or
with the well point in clay, which ever is more shallow.
These wells will be sampled and analyzed for volatile organics,
including DEE, n-propanol, xylene and TCFM. .Up to six selected soil
samples will be analyzed for the same parameters, if needed to verify the
presence of contaminants in the unsaturated zone. Based upon the results
of the investigation, up to three additional borings and wells will be
installed, sampled, and analyzed as above to establish the spatial limits
of on-site DEE contamination.
When the extent of soil and groundwater contamination is determined,
-------
iMT 3::::yi;:£ L:»ITS
City of Hiies
Aujust 1985
Arsenic
Surcharge above 300 «g/l
Surcharge above 350 09/1
Surcharge above 20 mg/1
Surcharge above 20 ag/1
(total)
Copper
Lead
Nickel
Silver
Zinc
Cyanide
BOD(5)
Suspended Solids
Phosphorus
Armenia
COO
Chlorine Demand
Fats. Oils, Grease
pH (must be)
Neat: Limited to 104°' at plant influent
Halogenated Hydrocarbons*
Chloroform
TMchloroethylene
Tetrachloroethylene
1,2-Oichloroe thane
Carton Tetrachloride
8TX
Aromatlcs*
Benzene
Chloro benzene
Oichloro benzene
5-Tetrachlorobenzene
Pentach 1 brobenzen*
Hexach 1 orobtnzent
Aromatlcs*
Benzene
Oil ore benzene
Dicnlorobenzene
5-Tetrachlorob«nzene
Pentach 1 orobenzeni
Hexachlorobenzent
Phenols*
Phenol
2-Chlorophenol
4-Chlorophenol
2.4-Oichlorophenol
2.4,6-Trichlorophenol
2.3-Oichloropnenol
1.1 og/1
0.69 ng/1
2.77 »g/l
3.38 »9/l
0.69 39/1
3.98 eg/1
0.43
2.61
1.20
Upper licit 1.000 09/1
Upper lieu 1,000 019/1
Upper liff.it 100 mg/1
Upper liait 100 09/1
450 »9/1
16.0 ag/1
100 ag/1
6.0 to 9.5
'No discharge above ISO0*
1.9 ug/1
27.0 U9/1
8.0 ug/1
9.4 ug/1
4.0 ug/1
13.0 ug/1
6.6 ug/1
20.0 ug/1
400.0 ug/1
38.0 ug/1
74.0 ug/1
7.2 ug/1
6.6 ug/1
20.0 ug/1
400.0-ug/l
38.0 ug/1
74.0 ug/1
7.2 ug/1
0.3
0.1 ug/1
0.1 ug/1
0.3 ug/1
0.1 ug/1
0.04 ug/1
940 ug/1
Pthalate Esters*
• Data obtained from U.S. EPA Treatability Manual, Volume 1.
EPA-£00/2-82-001a. September 1981.
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12
to four 4-inch galvanized steel wells with 4-inch diameter stainless steel
screen three feet long will be installed to dewater. Actual field
information may suggest more effective groundwater removal could be
accomplished with one or two sump wells.
Depending upon the amount of DEE and its concentration in soils above
the water table, it may be desirable to add an independent recovery process
to purge the aerated soils of volatiles. Except for a zone of sand with
clay binder at 11 to 13.5 feet, the profile above the clay at 23.5 feet is
logged as granular iwith fine or fine to medium sand and occasional gravel.
Either an enhanced volatilization or soil flushing method could be used.
, \
V. Screening of Alternatives
From the remedial action technologies evaluated, potential alter-
natives were identified that meet the remedial action objectives. These
potentially applicable alternatives were screened to determine those which
should be evaluated in detail. The following screening criteria were used
to eliminate those technologies not applicable to the U.S. Aviex site:
1. Technology not practical for this site because of site
characteristics.
2. Technology uses unproven technology.
3. Technology not consistent with the clean-up criteria established by
the Superfund Amendments and Reauthorization Act (SARA) of 1986.
"While the basic framework (of the remedial process) remains intact,
SARA does arM some new features and emphasis. The most significant
emphasis of SARA is on risk reduction through destruction or
detoxification of hazardous waste by employing treatment
technologies which reduce toxicity, mobility or volume rather than
protection achieved through prevention of exposure. SARA calls for
the Agency to prefer remedies that use treatment to permanently and
significantly reduce the toxicity, nobility, or volume of wastes
over remedies that do not use such treatment. In addition, SARA
requires that the Agency select a remedy that utilizes permanent
solutions and alternative treatment technologies, or resource
recovery technologies, to the maximum extent practicable." (From a
memorandum issued by J. Winston Porter, Assistant Administrator,
EPA: Titled: Interim Guidance to Agency Regional Offices Discussing
Issues Related to Selecting Superfund Site Remedies; dated Dec. 24,
1986.)
4. Requires excessively long periods of time to implement or to
effectively clean up site in relation to remedial action objectives.
5. Excessive relative costs.
6. Environmental considerations.
-------
13
If a particular remedial action alternative met one or more of the
above criteria then it was considered not appropriate for the site. A
summary of remedial alternative screening is presented in Table 7. The
following alternatives were deemed not appropriate for use at the U.S.
Aviex site.
On-Site Soils
No Action; No Treatment of On-site Soils
i
Not consistent with the clean-up criteria established by SARA of 1986.
Does not destroy or detoxify the waste, or provide a permanent solution.
Also is not consistent with remedial action objectives established for this
site.
Control leachate by removal of soils and off-site disposal in an
Act 64 landfill.
Not consistent with the clean-up criteria established by SARA of 1986.
Does not destroy or detoxify the waste, reduce its volume, or provide a
permanent solution in keeping with cradle-to-grave responsibilities.
Qn-Site.Groundwater
No Action A: No Treatment of Cn-site Groundwater.
Not consistent with the clean-up criteria established by SARA of 1986:
Does not destroy or detoxify the waste or reduce its mobility or volume.
Also not consistent with the remedial action objectives established for
this site.
No Action B: Continue with Existing Purge and Treatment System
Capture and treatment of on-site groundwater will continue to be
needed but in a combined configuration with off-site purge wells that could
result in elimination of an existing pur?6 well.
Collection with On-site Purge Well and Disposal by Qn-site Deep-well
Injection: Excessive relative cost (approximately $2,000,000 to permit and
install only). Not consistent with clean-up criteria established by SARA
of 1986. Does not destroy or detoxify the waste, or reduce its volume and
excessive time (up to two years) is required to obtain approval, if at all,
due to permit requirements.
Collection with On-site Purge Well and Disposal by Off-site Deep-well
Injection: Excessive relative cost (approximately $2,000,000 to permit and
install only). Not consistent with clean-up criteria established by SARA
of 1986. Does not destroy or detoxify the waste or reduce its volume,
excessive time required to obtain approval, if at all, (up to two years)
due to permit requirements. Capture and treatment of on-site groundwater
will continue to be needed but in a combined configuration with off-site
purge wells that could result in elimination of an existing purge well or
-------
LE 7
Remedial Alternative
On-Site Source Control-Soils
•-No Action
In-si tu-Aeration
In-situ-Flushing
Capping
Removal/Of f -Site
Disposal
- Aeration/641 Landfill
- Incineration/641 Landfill
I.A.3.C Removal/Of f-Slte
Landfill
Site
Conditions
SUMMARY
Tech
OF REMEDIAL ALTERNATIVE SCREENING
Implementation
' SARA Time frame
Relative
Cost
Not Consistent
Not Permanent Selection
Amenable
Amenable
With Modlf .
Amenable
Amenable
Amenable
Amenable
Proven
Proven
Proven
Proven
Proven
Proven
Consistent
Consistent
Not Consistent
Not Permanent Sol.
Not Consistent
Not Fully Consistent
Not Consistent
Acceptable
Acceptable
Acceptable
Moderate
Moderate
Moderate
Acceptable
Acceptable
High
High
High
High
Environmental Screen
Consideration Decisi >
Inconsistent with
remedial action obj.
Good
Good
Does not el Imlnate
source
Uses up Landfill Space,
Release of VOC's
Uses up Landfill Space
Uses up Landfill Space,
Release VOC's
E
R
R
R
R
R
E
Cn-Site Source Control -Groundwater '!
No Action A
No Action B
On-Site Collection,
Treatment with Off-Site
Disposal
On-Site Collection with
Off-Site Treatment/
Disposal
On-SCle Collection,
Disposal by On-Slte
Deep Well Injection
' On-Site Collection,
Disposal by Off-Site
Deep Well Injection
-
Amenable
i
Amenable
Amenable
Available
Underground
Formation-
Questionable
Available
Underground
Formation
Questionable
•
Proven
Proven
Proven
Proven with
Reservations
Proven with
Reservations
Not Consistent
Not Permanent
Consistent
Consistent
Consistent
Not Consistent
Not Consistent
-
Long-term
Long-term
Long-term
Moderate-term
Moderate-term
-
Acceptable
POT* High
Drain Acceptable
POTW High
Drain Acceptable
Excessive •
Excessive
Inconsistent with
Remedial Action Obj.
Need to Expand
Existing System to
Comply
Good
May not meet POIN
Standards
Questionable
Questionable
E
E
R
R
E
C
-------
Table 7 (Cont'd)
Remedial Alternative
Collect, Store, and
Disposal Untreated by:
Off-Site Deep Hell
Injection
. On-Site Deep Well
Injection
Site
Conditions
Available
Underground
Formation
Questionable
Available
Underground
Formation
Questionable
Tech SARA
i
Proven with Not Consistent
reservations
Proven with Not Consistent
reservations
Implementation
Time frame
Long-term
Long-term
Collect, Temporary Amenable
Storage, Discharge
Untreated Croundnater to
Surface Drain
Collect, Temporary Amenable
Storage, Discharge to
Nilcs POTW
Collect, Transport
Dack to Site, Store,
Treat/Disposal
Air stripping with
Dome-Huntly discharge
Air stripping with
Niles POTW discharge
Steam stripping with
Dome-Huntly discharge
Steam stripping with
Niles P01W. discharge
Carbon adsorption
with Uomo-Muntly
discharge
Carbon adsorption Amenable
with Niles P01W
discharge
Proven, storage
not required
Proven, storage
not required
Not consistent
Consistent
Proven, storage
not required
Consistent
Long-term
Long-term
Long-term
Relative
Cost
Excessive
Excessive
High
Amenable
Amenable
Amenable
Amenable
Amenable
Proven, storage
not required
Proven, storage
not required
Proven, storage
not required
Proven, storage
not required
Proven, storage
not required
Consistent
Consistent
Consistent
Consistent
Consistent
Long-term
Long-term
Long-term.
Long-term
Long-term
Acceptable
High
Acceptable
High
Aoceptable
High
Environmental Sere
Consideration Dec(|
Questionable
Questionable
Acceptable Would hot meet HPOES
POTW may not accept
Good
POTW may not accept
Good
POTW may not accept
Good
POfW may not accept
H
R
A
ft
R
-------
Table 7 (Cont'd)
Remedial Alternative
Management Migration Croundwater
(off-iite/on-iitc)
No Action
Monitor Only
Collect, itorc, trans-
port to treat system
via pipeline with off-
site treat/disposal
Air stripping tilth
Bame-Huntly discharge
Air stripping with
Niles POTN discharge
Steam stripping with
Dome-Huntly discharge
Steam stripping with
Niles POIW discharge
Carbon adsorption
wiIn Game-Hunt Iy
discharge • .
/
Carbon adsorption
with Niles POTW
discharge
Site
Conditions
Tech
SARA
Implementation
Tlmeframe
Relative
Cost
Amenable
Amenable
Amenable
Amenable
Amenable
Amenable
Amenable
No Clean-up
No permanent solution
Not consistent
Not • permanent
•olutlon, not
consistent
Proven, but
Impractical|
storage not
required
Proven, but
Impractical|
storage not
required
Proven, but
Impractical)
storage not
required
Proven, but
Impractical|
storage not
required
Proven, but
Impractical |
storage not
required
Proven, but
Impractical\
storage not
required
Consistent
Consistent
Consistent
Consistent
Consistent
Consistent
Long-term
Acceptable
Long-ton*
Long-term
!' Long-term
Long-term
Long-term
Long-term
Acceptable
High
Acceptable
High
Acceptable
High
Environmental
Consideration
Inconsistent with
Remedial Action Obj.
Inconsistent with
remedial action obJ.
Scrreii
Decision
Siting
POTN may not accept
Siting
POTN may not accept
Siting
POTN may not accept
-------
TabU - (Cont'd)
Site j if Implementation
Remedial Alternative Conditions T^rf II me frame
Relative
Cost
Alternative Drinking Water Supplies
Howard Tnp.
Municipal Well Syst.
Connect to Nllos
Municipal Syst.
Install deepened
Municipal Syst.
Individual Domestic
Well Treatment
Provide Bottled Water
to Affected Residence
Relocate Affected
Residence
Pro
Provs
Proven
• Proven but
limited
Proven but
not desirable ,
Not Feasible No realistic
solution, not
consistent
Short-term
Permanent
Short-term
Permanent
Short-term
Permanent
Short-term
Short-term
Long-term
Permanent
f $1,000,000
> $1,000,000
< $1,000,000
< $1,000,000
Excessive
Relative Cost
Excessive
Relative Cost
' Environmental Sc|»
Com 1 deration 6cg 1$
Meets remedial
• action ob'ji
. Meets remedial
> act 1 Oft obj.
Must confirm deep
aquifer protected
Marginal
Soclaily unacceptable
Socially unacceptable
fl
R
n
R
E
E
C « Eliminate from further consideration,"
R - Retain for detailed evaluation.
-------
14
increasing the flow to the existing air stripper.
Cm-Site and Off-Site Groundwater
No Action A: No treatment of on-site or off-site groundwater.
Not consistent with clean-up criteria established by SARA of 1986.
Does not destroy or detoxify the waste, reduce its volume or mobility, or
provide a permanent solution. Also not consistent with the remedial action
objectives established for this site.
Monitoring Only: Not consistent with clean-up criteria established by
SARA of 1986: Does not destroy or detoxify waste, reduce its volume or
mobility, or provide a permanent solution. Also not consistent with the
remedial action objectives established for this site.
Collection with Purge Well(s) and Disposal by Off-site Deep Well
injection: Excessive relative cost (approximately $2,000,000 to permit and
install only). Not consistent with clean-up criteria established by SARA
of 1986. Does not destroy or detoxify the waste, or reduce its volume,
excessive time required to obtain approval, if at all, (up to two years due
to permit requirements).
Collection with Purge Well(s), and Discharge of Untreated Groundwater
to a Surface Drain: Not consistent with clean-up criteria established by
SARA of 1986. Does not destroy the waste, reduce its volume, or provide a
permanent solution and is not consistent with remedial action objectives
established for this site.
Provide Bottled Water to Affected Residents: Not consistent with
clean-up criteria established by SARA of 1986. Does not destroy or
detoxify the waste, reduce its volume or mobility, or provide a permanent
solution. The cost is excessive when compared to other alternatives.
Relocate Affected Residents: Not consistent with clean-up criteria
established by SARA of 1986. Does not destroy or detoxify the waste,
reduce its volume or mobility, or provide a permanent solution. The cost
is excessive when compared to other alternatives-.
VI. Description of Alternatives
Acceptable alternatives to address the remedial oojectives at the U.S.
Aviex site have two goals or objectives. First, they must control the on-
site source of contamination, and second, they must control and treat the
on-site and off-site contaminant plumes. The on-site control alternatives
are directed toward sub-surface soil contamination through in-situ
treatment or through leachate control by capping or- excavation and
incineration. An outline and discussion of these alternatives follows.
A. On-site Source Control - Soils
1. In-situ treatment
a. Aeration
-------
.15
b. Soil flushing
2 . Leachate Control
a. Capping
b. Excavate and Incinerate
B. Qn-site Source Control - Groundwater
1. On-site Collection and Treatment, Off -site Disposal
a. Air Stripping
b. Steam stripping
c. Carbon Adsorption
C. Management of Migration - Cn-site and Off-site Groundwater
1. Cm-site and Off-site Collection, On-site Treatment with
Off-site Disposal
Alternative A. 1 . a. Aeration
An aeration system pulls air through the unsaturated soils, extracting
volatile organic compounds (VCCs) from the pore spaces in the soil. The
aeration equipment includes a system of air intake wells, air withdrawal
wells, piping and a blower. Air intake wells are placed around the
perimeter of the contaminated areas. Air withdrawal wells are placed in
the center of the contaminated areas. A blower draws atmospheric air into
the intake wells, through the soil pore space, and into the withdrawal
wells. A vapor carbon absorber in line with the blower would remove the
\JOCs from the air before discharging into the atmosphere. A plastic
membrane placed over the contaminated area ensures that air removed from
the withdrawal well is drawn through the pore space and not from the
surface near the withdrawal wells.
Alternative A. l.b. .Soil
A soil flushing system removes VXs from the contaminated soils by
allowing water (possibly mixed with surfactants) to flow through the soil
pore space. The contaminated water is then removed from the ground by the
on-site purge wells and treated in the selected treatment system. Soil
flushing takes place to some extent naturally due to the infiltration of
rainwater in the cracks of the existing pavement that covers the
contaminated areas. Soil flushing would be accomplished by an underground
system of perforated pipelines below grade in the areas of contamination.
The water supply could be obtained from an on-site well drilled to the
uncontaminated aquifer or by connecting to the Niles Municipal Water
System. The well would be constructed in such a way as to prevent
contamination of the lower aquifer. Water (with a surfactant supplied
through a chemical feed pump if required) would be continually applied to
the subsurface soils.
Leachate production from the contaminated soils can be controlled by
capping the surface to minimize surface water infiltration or eliminated by
removing the soils.
Alternative A. 2. a. Capping
The capping alternative reduces the permeability of the site surface,
-------
16
minimizing infiltration. The multi-layered cap would consist of four feet
of clay, a twenty mil PVC synthetic membrane, eighteen inches of sand., and
six inches of top soil. The top of the cap would be seeded, nulched aiad
fertilized. Post closure nonitoring would .be required to ensure continued
effectiveness of the cap. The capping alternative would require excavation
of approximately six feet of soil prior to installation because of site
limitations. The excavated soil would be incinerated at a RCRA compliant
facility.
Alternative A.2.b. Excavation and Incineration
Excavation of the contaminated soils is complicated by the depth of
the soils to be removed and their proximity to buildings. Sheet piling
will be necessary to protect the adjacent buildings during excavation.
Since the required excavation depth, twenty feet, exceeds the depth that
cantilever sheet piling may be used, a braced cofferdam system on all sides
of the excavations will be necessary. Excavated soils would be disposed of
at a RCRA approved landfill after treatment by incineration. The excavated
area would be bacJcfilled with off-site granular soils and the asphalt and
concrete surfaces restored as required.
Alternative B.I. On-site Collection and Treatment with Off-site
Disposal
On-site treatment can be accomplished with air stripping, steam
stripping, or carbon adsorption. Off-site disposal options include
discharge to the St. Joseph River via the Bame-Huntly Drain or to the Niles
wastewater treatment plant POTW. All three treatment options require
removal of the groundwater with on-site purge wells and from a separate
well point purge area on-site designed specifically to capture the zone of
DEE found and isolated on-site.
The following values were used as the basis of the design and cost analysis
for each treatment system:
Flow Rate 270 gal/min
Temperature 55 *F
Contaminant Loading
1,2-DCA 150 ppb
1,1.1-TCA 150 ppb
1,1-DCE 3 ppb
Trans-l,2-DCE 18 ppb
PCE <1 ppb
B-T-X <1 ppb
(Benzene-Toluene-Xylene)
DEE 210 ppb
TCFM 17 ppb
DCTM <1 ppb
Effluent concentrations from each treatment system treating the 10~6 risk
plume groundwater are estimated below:
Air Steam Carbon
stripping stripping Artenrpt ion
-------
17
1,2-DCA 50 ppb <1 ppb <1 ppb
1,1,1-TCA <1 ppb <1 ppb <1 ppb
1,1-DCE <1 ppb <1 ppb <1 ppb
Trans-1 , 2-DCE <1 ppb <1 ppb
-------
18
shallow groundwater zone underlain by clay.
Effluent from any of the treatment options could be discharged to the
Bame-Huntley Drain or to the Niles wastewater treatment plant. Discharge
to the Bame-Huntley Drain would require a National Pollution Discharge
Elimination System (NPDES) permit. U.S. Aviex has a NPDES permit for its
present discharge, This permit would have to be modified for the increased
flow and contaminant loading. To discharge to the Niles wastewater
treatment plant, a pipeline must be constructed to the nearest sewer with.
adequate capacity for the flow. This sewer is located near the inter-
section of 17th and Oak Streets, approximately 2.5 miles from the U.S.
Aviex site. Currently the wastewater treatment plant has sufficient
capacity to accept the wastewater flow.
Flow rate and influent concentration would be identical to that of the
on-site treatment alternatives. Off-site treatment would be at the Niles
wastewater treatment plant. A pipeline would be constructed to discharge
the purged groundwater to the plant. An existing sanitary sewer has
adequate capacity to handle this flow.
Alternative C.I. Management of Migration of Groundwater. On-site
Treatment with Off-site Disposal
This alternative may be divided into two options. The difference
between the options is the extent of the contaminant plume capture. In the
first option, the wells would be placed off-site_to capture the 10~6 risk
plume. In addition, one of the on-site wells would control the on-site
leachate (4 wells total). A total volume of 500 gal/min of groundwater
would be treated and disposed of. The second option would also use one on-
site well but would involve four wells to control off-site leachate
migration (5 wells total). These wells, placed at different locations than
the wells in the first option, would collect groundwater at a rate of 620
gal/min, capturing the migrating flow from the primary contaminant plume.
Each option also requires the wellpoint collection of 20 gal/tnin of on-site
groundwater contaminated'with DEE.
The following values were used as the basis for the design and cost
analysis for each treatment system for the 10~6 risk plume:
Flow Rate 500 gal/tain
Temperature 55°F
Contaminant Loading
1,2-DCA . 510 ppb
1,1,1-TCA 240 ppb
1,1-TCE 13 ppb
Trans-l,2-DCE <1 ppb
PCE <1 ppb
B-T-X <1 ppb
DEE 900 ppb
TCFM 16 ppb
-------
19
B-T-X <1 ppb
DEE 900 ppb
TCFM 16 ppb
DCFM <1 ppb
Effluent concentrations from each treatment system treating the 10~6 risJc
plume groundwater are estimated to be:
Air Steam Carbon
Compound Stripping Stripping Adsorption
1,2-DCA 160 ppb <1 ppb <1 ppb
1,1,1-TCA <1 ppb <1 ppb <1 ppb
1,1-DCE <1 ppb <1 ppb <1 ppb
Trans-l,2-DCE <1 ppb <1 ppb <1 ppb
PCE <1 ppb <1 ppb <1 ppb
B-T-X <1 ppb <1 ppb <1 ppb
DEE 275 ppb <1 ppb <1 ppb
TCFM <1 ppb <1 ppb <1 ppb
DCFM <1 ppb <1 ppb <1 ppb
The following values were used as the basis for the design and cost
analysis for each treatment system for the primary plume:
Flow Rate Total 620 gal/tain
Temperature 55°'
Contaminant Loading
1,2-DCA 150 ppb
1,1,1-TCA . 240 ppb
1,1-DCE 12 ppb
Trans-l,2-DCE <1 ppb
PCE 4 ppb
B-T-X - 10 ppb
DEE 650 ppb
TCFM 13 ppb
DCFM <1 ppb
Effluent concentrations for each treatment system treating the primary
plume groundwater are estimated to be:
Air Steam Carbon
Compound Stripping Stripping
1,2-DCA 50 ppb <1 ppb <1 ppb
1,1,1-TCA <1 ppb <1 ppb <1 ppb
1,1-DCE <1 ppb <1 ppb <1 ppb
Trans-l,2-DCE <1 ppb <1 ppb <1 ppb
PCE <1 ppb <1 ppb <1 ppb
B-T-X <1 ppb <1 ppb <1 ppb
DEE 200 ppb <1 ppb <1 ppb
TCFM <1 ppb <1 ppb <1 ppb
DCFM <1 ppb <1 ppb <1 ppb
Each of these alternatives has several options. Qn-site treatment can
be accomplished by air stripping, steam stripping, or carbon adsorption.
Off-site disposal options include discharge to the St. Joseph River via
the Bame-Huntley Drain or discharge to the Niles wastewater treatment
plant as described earlier. In either collection alternative, 10~6 risk
plume control or primary plume control, a groundwater monitoring program
-------
20
will be implemented to ensure that the desired degree of plume capture is
occurring.
An alternative with off-site treatment and disposal is also considered
for the combined collection alternative. The collection is the same as
above but flushing fluids discharge to the Niles FUIW.
•
VII. Sunrrory of the Comparative Analysis of Alternatives
Hie alternatives described above were found, in the FS screening, to
merit detailed analysis. The analysis of these alternatives measured
against the appropriate criteria follows.
1. Overall Protection of Human Health and the Brwironnent addresses
whether or not a remedy provides adequate protection, and describes how
risks are eliminated, reduced or controlled through treatment engineering
controls, or institutional controls.
The soil is treated to eliminate the risk from exposure through
ingest ion or inhalation of contaminated soil. Alternatives for treatment
of the contaminated soil through in-situ treatment reduce the risk to the
public health and the environment.
The capping alternative prevents exposure to contaminated soil and
reduces the production of contaminated grouhdwater (leachate). The
continued effectiveness of this alternative is dependent upon land use
restrictions and maintaining the integrity of the cap.
The on-site treatment of contaminated groundwater alternatives reduce
the risk to human health and the environment by eliminating the source of
exposure as well as eliminating potential contamination of off-site
groundwater. Restricting the use of on-site groundwater during the period
of treatment eliminates the risk of exposure through ingestion.
Management of the migrating off-site groundwater contaminants through
collection and treatment protects the public health and the environment.
During the period of treatment, groundwater use will be restricted through
institutional controls.
2. Compliance with ARARs addresses whether or not an alternative will
meet all of the applicable or relevant and appropriate requirements of
other environmental statutes and/or provide grounds for invoking a waiver.
ARARs are summarized in Table 8 for each alternative.
The Clean Air Act, 40 CFR 50 and 52, which implements and sets rules
for regional air pollution control and establishes Ambient Air Quality
Standards, is applicable to discharges of toxic substances to the
atmosphere during waste handling or treatment. Tnis Act is administered
by Michigan Department of Natural Resources (MDNR) Air Quality Division
under Michigan Act 348. The Air Quality Division is authorized to ensure
that a person does not cause or permit the emissions of an air contaminant
in quantities that will cause injurious effects to human health or safety,
-------
21
|l life, plant life of .significant economic value, or property "or
unreasonable interference with "the comfortable enjoyment of- life and
property." The Air Quality Division requires appropriate air monitoring
of emissions and compliance with Federal .PSD regulations, Federal NSPS,
aod NESHAP standards.
These standards will be met during treatment of soil and groundwater
through the use of discharge control systems designed to meet the
requirements of Rules 201 and 203 of Michigan Act 348. Tne capping and
excavation and incineration alternatives will not meet Michigan Act 348
requirements and standards. However, only air monitoring to demonstrate
compliance with Rule 901 of Act 348 has been required for installation of
slurry walls.
The Clean Water Act 40 CFR regulates point discharges to navigable
waters. This Act is administered by the MDNR under Michigan Act 245 and
establishes surface water quality standards "to protect the public health
and welfare, to enhance and maintain the quality of the water, to protect
the State's natural resources." The MDNR oversees point discharge
standards as promulgated by the Federal NPDES program under this Act. The
groundwater treatment alternatives (air stripping, steam stripping, and
carbon adsorption) will provide levels of efficiency meeting NPDES permit
standards. Part 9 of Michigan Act 245 requires reporting of critical
materials. At this site the defined critical materials include benzene,
Trichloroethylene, and Tetrachloroethylene. The alternatives"
meet the requirements for an effluent discharge permit and the terms
and conditions of the permits effluent standards and limitations.
The State has identified Michigan Act 245, Part 22, which regulates
groundwater quality, as an ARAR. The purpose of the groundwater quality
regulations is "to protect the public health and welfare and to maintain
the quality of groundwater in all usable aquifers for individual, public,
industrial and agricultural water supplies and provide for the
nondegradation of groundwater quality in usable aquifers" by preventing
discharge into the groundwater. Michigan Act 245 is not applicable since
*no discharges into the groundwater are proposed. Michigan Act 245 is not
relevant or appropriate to establishing clean-up levels or areas of
attainment at the site since no standards • are provided. However, the
'groundwater treatment alternative proposes treatment to the 10~6 risk
levels which will reduce contaminant concentration levels below the MCLs.
Installation of all wells in the aeration, flushing, and groundwater
treatment alternatives will conform to Michigan Act 315 and the
administrative rules which regulate construction, operation, and
abandonment of such wells.
Michigan Act 98 regulates supervision and control over sewage systems
including planning, construction, operation and maintenance. The
Jwater treatment alternatives (air stripping, steam stripping and
adsorption) will meet the requirements of this Act.
Michigan Act 346 regulates inland lakes and streams. Act 346 requires
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TAULE 8
ARARs FOR THE U.S.
Regulation
FEDERAL
Clean Air Act,
Section 101
40 CFR 52
40 CFR SO
Clean Water Act,
Section 208
40 CFR 122
40 CFR 125
40 CFR 131
40 CFR 136
40 CFR 261
40 CFR 262
40 CFR 263
Requirement
Implementation of regional
air pollution control
programs.
Rules for Implementation of
regional air quality plan.
Air quality standards.
Actions consistent with
water quality management
program.
NPUES permit regulations.
Criteria for NPDES permit.
Enforcement jurisdiction over
Discharges granted to States.
Adherence to sampling
Procedures.
Definition and Identification
of ha zards( waste.
Regulations for generation
of haiardous waste
Regulations for transport of
hazardous waste
Regulated Action
or Condition
Emissions during excavation,
treatment of soil and
groundwater
Emissions during excavation,
treatment of soil and
groundwater
Emissions during excavation,
treatment of soil and
groundwater
Discharges to Bame-lluntley Drain
Discharges to Barae-lluntley Drain
Discharges to Bame-lluntley Drain
Discharges to Bame-lluntley Drain
Discharges to Bame-lluntley Drain
Excavated materials and groundwater
treated residuals.
Groundwater treatment residuals hauled
off-site.
Groundwater treatment residuals hauled
off-site.
Alternative
A.I.a.
X
A.l.b. A.2.a* b.aiicj C.
X
X
X
X
X
X
x
X
X
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Table 8 (Page 2 of 3)
RcgufaTlon
40 CFfl 264
Subpart X
40 CFR 268
Subparts C
and D
40 CFR 403
40 CFR 141
Requirement
Standards for environmental
performance of miscellaneous
treatment units.
Land-banned waste Materials.
Pretreatment standards for
discharge to local POTU.
Established maximum contami-
nant levels (HCls) for
drinking water quality.
H^fa
Regulated Act
or,Condition
Physical/chemical treatment.
Would apply to certain solvent-
was les.
Discharges to POTW after Installation
of extraction wells .but before
Installation of on-slte groundwater
treatment plant.
Groundwater at the site.
Al tentative
.A.I.a. A. l.b. A.2.a. O.and C. A.2.b.
Executive Order Requires state and local
12372 coordination and review of
40 CFR 29 EPA-asslsted projects.
U.S. Avtex Site Is a CEHCLA site.
State
ACT 348
ACT 31S
Act 64
Part 2 and 3
Regulates air emissions and
requires monitoring of air.
Regulates permitting, construc-
tion, and abandonment of wells.
Requirements for Identifica-
tion, recordkeeplng, and
management of hazardous waste.
In-sltu soil treatment RCRA, Cap
Monitoring wells on-slte and near
site. Groundwater extraction wells.
Generated groundwater treatment
residuals and excavated materials.
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Table 8 (Page 3 of 3)
Regulation Requirement
ACT 64, Regulations for con-
Part 5 struction and licensing
treatment facility.
ACT 64, Specifies technical
Part 6 standards for locating
operating and closing
a hazardous waste
facility.
ACT 245 Rules for reporting
Part 9 discharges to state
waters.
ACT 245, Rules for NPOES permit.
Part 21
ACT 98 Supervision and control
of sewage systems
ACT 346 Permit for construction
Section 3 in "bottom land."
ACT 368 Authority to safeguard
public health, determine
imminent danger.
Regulated Action
or Condition
Groundwater treatment
Groundwater treatment
Alternative
A.2.a. A.l.b. A.2.a O.and C. A.2.b.
Discharges from groundwater
treatment.
Discharges from ground-
water treatment.
Construction and operation
of groundwater treatment.
Buried pipeline for groundwater
water collection and discharge.
Any activity
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22
"construct., enlarge, extend, remove, or-place a structure on bottomland."
•rompliance with permit regulations to "dredge or fill bottomland" or to
^it_ - - - - - - --
Act 346 specifies the technical information and criteria required for
evaluating and reviewing the proposed activities. The construction of
surface water discharge piping for disposal of treated ground-water will
meet these requirements.
40 CFR 260-264 RCRA Subtitle C, regulates the generation,
transportation, storage, treatment and disposal of hazardous wastes
generated in the course of remedial action. The program is administered
under Michigan Act 64. The administrative rules requiring identification
of hazardous wastes and compliance with management requirements will be
met for carbon adsorption from the groundwater treatment alternative and
for the emission control system of the air stripping or steam stripping
alternatives. Requirements for construction and operation of a hazardous
waste treatment facility in Part 5 and Part 6 of Michigan Act 64 will be
met by the treatment alternatives.
The Safe Drinking Water Act, 40 CFR 141, establishes Maximum
Contaminant Levels (MCLs) for drinking water quality. The treatment
alternatives for on-site and off-site groundwater will meet the MCLs
within the area of attainment based upon clean up levels of 10~6 total
risk. Risks associated with the MCLs range from 10~4 to 10~6.
3. Long-term Effectiveness and Permanence refers to the ability of a
remedy to maintain reliable protection of human health and the environment
over time once cleanup goals have been met.
Both the soil flushing and the aeration alternative for on site soil
source control provide long-term effectiveness and permanence through
treatment. Under the soil flushing alternative levels of contamination
are reduced until the generated leachate (flushing fluids) no longer acts
as a source of groundwater contamination.
Aeration, through enhanced volatilization of the contaminants in the
vadose zone, removes the source of the contamination. Leachate will no
longer be produced.
The RCRA cap reduces the amount of surface water percolating through
the contaminated vadose zone soil and the leachate production. Untreated
contaminated soils will remain on the site, however, posing a long term
threat to groundwater quality. The cap maintenance required also reduces
the permanence of this alternative.
The excavation and incineration alternative effectively and
permanently treats the contaminated soil on the site. Disposal~~of the ash
off-site represents a future environmental hazard and adds to the problem
of hazardous waste disposal.
The pump and treat alternatives provide for containment and treatment
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23
of the 'on-site contaminant groundwater and the off-site plume, treating to
levels which permanently reduce the potential for further degradation of
the aquifer,. The pump and treat alternatives also eliminate the health
risks of consuming contaminated groundwater and reduce the threat to
downgradient municipal wells. Discharge concentrations levels from the
treatment methods comply with NPDES permit standards. When clean-up
levels have been reached, this alternative will provide both long term
effectiveness and permanence.
4. Reduction of Toxicity, Mobility or Volume is the anticipated
perform- ance of the treatment technologies a remedy may employ. Toxicity
of con- taminants in the on-site soil will be reduced through treatment.
The soil flushing alternative reduces the potential for off-site movement
of the contaminants from soil by treatjnent of the flushing fluids.
Groundwater treatment through pump and treat alternatives reduces the
contamination of groundwater under the site and controls migration of the
off-site plume.
5. Short-term Effectiveness involves the period of time needed to
achieve protection as well as the adverse effect on human health and the
environment that may be posed during the construction and implementation
period until cleanup goals are achieved.
Short-term effects of the in-situ soil source control alternatives
would be negligible. Contaminants are immobilized in the subsurface area
and carried to the surface for treatment by a closed circuit extraction
system which minimizes the potential for risk to the public health and the
environment. Treatment of. the VCCs in the aeration alternative and
contaminant- ladened fluid in the flushing alternative, operate in
compliance with appropriate permit requirements.
The RCRA cap alternative introduces minor increases in the potential
for exposure to subsurface soils and increases in the risk to the
environment during the excavation period. The excavation and incineration
alternatives could increase the risk of exposure to low levels of \TOCs
through either vapor emissions or particulate dispersion.
Qn-site groundwater source control and plume migration management
alternatives depend upon groundwater usage restriction, in the form of
advisories, for short term effectiveness. Emission treatment on the
discharge side of the stripping tower will minimize exposure due to on-
site treatment. The design of this system will mee_ the technical
requirements of applicable air emission control regulations.
Short term effectiveness of the on-site groundwater treatment
alternatives assumes that discharges of treated water from the larger
capacity stripping system required to treat the on-site and off-site
groundwater and the soil flushing fluids, will remain within the limits of
the NPDES permit in effect for the currently operating system.
6. Implementability is the technical and administrative feasibility of a
remedy,including the availability of goods and services needed to
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24
implement the chosen solution.
A purge and treat system for the groundwater is a necessary component
of the in-situ treatment of soil contamination by soil flushing. This
system may be difficult to design due to the stratigraphic variability at
the site. A pilot study may be required to determine the number of wells,
air f-low rates, and other parameters.
While capping or excavation and incineration are available
technologies for leachate control, a limiting factor is the availability
of a landfill and incinerator.
On-site groundwater control and on and off-site management of
migration alternatives, properly designed, will provide containment,
collection, and treatment, and meet the objectives of site remediation.
Air stripping technology can be designed to improve removal efficiency
to meet POIW pretreatment standard and NPDES permit requirements.
Discharge alternatives require use of existing lines to surface drainage
or the construction of a pipeline to the existing sewer line.
7. Cost includes capital, operation and maintenance costs.
Total costs for the alternatives other than no action are compared
in Table 9 below.
TABLE 9
ALTERNATIVES TOTAL COST
Qn-site Source Control of Soils
In-situ aeration $ 515,000
In-situ flushing 163,000
RCKA cap 1,003,000
Excavation and incineration 21,105,000
On-site Source Control of Groundwater with Cn-site Treatment and
Off-site Disposal
Air stripping ;
surface discharge $ 2,369,500
POIW 5,237,700
Steam stripping
surface discharge 5,313,500
POIW 8,171,700
Carbon adsorption
surface discharge 3,180,100
POIW 6,048,300
* Relevant only if there is a No Action Alternative for off-site
groundwater treatment.
Management of Plume Migration with Off-site and On-site Collection and Cn-
site Treatment with Off-site Disposal
Air stripping
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25
surface discharge
10~6 plume 2,888,100
primary plume 3,359,500
POIW
10~6 plume 7,348,900
primary plume 8,651,900
Steam stripping
surface discharge
10~6 plume 8,321,600
primary plume 10,390,300
PCflW
10~6 plume 12,772,400
primary plume 15,672,700
Carbon adsorption
surface discharge
10~6 plume 5,714,300
primary plume 6,023,200
POIW
10~6 plume 10,175,300
primary plume 11,315,600
8. Support Agency acceptance indicates whether, based on its review of
the RI/FS, the support agency (State) concurs, opposes, or has no content
on the preferred alternative.
The State of Michigan has been notified of USEPA's choice of a
preferred alternative and concurs with tlie selected alternative.
9. Community acceptance
A Responsiveness Summary detailing USEPA's response to each
significant comment submitted during the comment period is attached to the
PCD.
VIII. The Selected Remedy
The selected remedy for the U.S. -Aviex site, soil flushing
(Alternative A.l.b.) and collection of on-site and.off-site groundwater
with treatment by air stripping (Alternative C.I-.'), addresses both sources
of contamination and the resulting off-site plume.
Control of the sources of contamination will be accomplished by
flushing the contaminants out of the vadose zone soil. Tnese flushing
fluids will then be collected along with the on-site contaminated
groundwater through a system of purge wells. Control and collection of
off-site contaminated groundwater will be accomplished by a series of
purge wells installed in the contaminant plume. Hie collection system
will be designed to contain the plume and prevent further degradation of
the aquifer. . :
The design phase will include studies of sufficient scope to
determine operating parameters and flushing system efficiencies. The
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26
effectiveness of the flushing systan will be evaluated after it has been
in operation for five years. This evaluation will be based on an analysis
of soil and groundwater samples for indicator chemicals. If there is no
significant reduction in the contaminant levels in soils and if, after
regular sanpling and analysis, we find that the groundwater contamination
continues to exceed 10~6 total risk, an alternate source control remedy
will be identified in a new Feasibility Study and justified in a new
Record of Decision.
The proposed area of attainment for treatment of the contaminated
groundwater is the 10~6 total risk plume. This 10~6 total risk plume is
that volume of water which contains contaminants at concentrations that
pose an increased lifetime risk of one cancer case in a population of one
million people. Restoration of the plume will meet drinking water
standards, eliminating the risk to public health through consumption of
contaminated groundwater. Impact, if any, on the Niles municipal wells
approximately two miles west of the site will also be reduced.
Determination of the potential impact on the Niles municipal wells in
the USEIA Ehdangerment Assessment was based on a worst case scenario - no
action with continuous release of contaminants at the site. Using this
scenario, analysis indicated that no contaminants of concern would be at
unacceptable levels at the municipal wells at the time of arrival of the
plume after approximately seventy years. The proposed alternative treats
the sources of potential contamination and virtually eliminates any
potential for impact on the municipal wells.
•Die contaminated groundwater collected from the on-site and off-site
purge wells will be treated on-site by air" stripping. The treated
groundwater will be discharged to the surface waters through local
drainage in compliance with NPDES permit requirements. The efficiency of
this treatment alternative will produce an effluent with contaminant
levels in an order of magnitude less than the chronic toxicity criteria.
Appropriate monitoring of the effluent will insure that permit
requirements are met during operation. Installation of purge wells and
collection or discharge systems for off-site groundwater will meet state
and local regulations regarding 'easements and construction standards.
Discharge of \KXs to the atmosphere will: be managed through emission
controls designed to meet the requirements of state construction and
operation air quality permits. Monitoring will insure that air quality
standards are met.
There will be no additional risks to the community or on-site workers
during the flushing, collection and treatment of the contaminated
groundwater by the air stripper. Workers will use appropriate protective
clothing (including respiratory protection) and adhere to an approved site
safety plan.
The total estimated cost for the proposed remedies is $3,024,100.
This estimated cost includes the on-site flushing of the contaminated soil
($163,000) and the cost of the treatment of on-site and off-site
contaminated groundwater ($2,888,100).
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IX. Statutory Determinations
Section 121 of CERCLA requires that, at a minimum, the selected
remedy shall:
* Be protective of human health and the environment.
* Attain ARARs or provide grounds for invoking a waiver.
* Be cost-effective.
* Utilize permanent solutions and alternative treatment
technologies or resource recovery technologies to the maximum
extent practicable.
* Address whether the preference for a treatment that reduces
toxicity, mobility, or volume as a principle element is
satisfied, or provides an explanation as to why it is not
satisfied.
A. Protection of Hunan Health and the Qrvironnent
The existing and potential risk to human health come about through
Exposure to contaminated groundwater and from the off-site plume through
consumption and domestic use. This risk is limited to accidental or
uninformed use only, since a municipal water system has been extended into
the affected area. On a long term- basis, there is the potential for
exposure beyond the current area of contamination if the plume continues
to migrate. The selected remedy eliminates potential risks and ensures
adequate protection of human health and the environment through
containment and ^reatment of the on-site plume within the area of
attainment to 10~6 risk levels. This level of treatment represents
contaminant levels which, at a minimum meet drinking water standards.
Short term risks may be posed during the treatment process by the
discharge of treated water to surface drainage and_by emissions to the
atmosphere from the air stripper. However, the treatment process will,
treat groundwater to levels which will meet the NPDES permit requirements
and cause no unacceptable short term risks by implementation of the
remedy. Atmospheric emissions will meet the standards of the Federal and
State Air Pollution Control Acts.
B. Attainment of Applicable or Relevant and Appropriate Requirements
The applicable or relevant and appropriate Federal and State
requirements (ARARs) that were considered for the U.S. Aviex site and
. satisfied through the selected remedy are listed in Table 10. The
^selected remedy attains Federal and State ARARs.
Chemical specific ARARs address the clean up levels for indicator
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10
U.S. Aviex
Selected Remedy ARARs
I. Federal Requirements
A. Groundwater Protection
1. Clean up levels for indicator
chemicals (Benzene, TCE, 1,2-DCA,
1,1-DCE, 1,1,1-TCA)
B; Surface Water Protection
1. Regional management program
2. NPDES - discharge of treated
groundwater
C. Construction of Treatment System
and Disposal of Treatment Residuals
D. Protection of air quality during
Treatment -
E. Generation, Transportation, Storage,
Treatment and Disposal of Hazardous
Wastes
II. State of Michigan Requirements
A. Surface Water Protection ?
1. Discharges from groundwater
treatment
B. Air Quality Protection
C. Treatment System Installation
D. Treatment Residuals
E. Hazardous Wastes
40 CFR 141
CWA, Section 208
40 CFR 122
40 CFR 125
40 CFR 131
40 CFR 236
40 CFR-260-263
Clean Air Act,
Section 101
40 CFR 50, 52
RCRA Subtitle C
40 CFR 260-264
Act 245, Part 9, 21
Act 348
Act 98
Act 846, Section 3
Act 315
Act 64, Parts 2, 3,
5, 6
Act 64
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28
deals. "Die Safe Drinking Water Act, 40 CFR 141, establishes maximum
inant levels (MGLs) for drinking water quality. MZLs will be
reached or exceeded within the 10~6 risk level area of attainment. Action
specific ARARs relate to the installation and operation of the groundwater
collection and treatment alternative, the discharge of treated
groundwater, air emissions, and disposal of treatment generated wastes.
Permit requirements for installation of wells in the groundwater
collection system pursuant to Michigan Act 315, are relevant and
appropriate and will be met. RCRA Subtitle C, 40 CFR 260 through 264 and
40 CFR 100 through 199, regulate the generation, transportation, storage,
treatment, and disposal of hazardous wastes generated in the course of
remedial action. The construction design, monitoring operation, and
closure of hazardous facilities is also regulated. This program is
administered by MDNR under Act 64. "Die requirements are applicable to the
groundwater system and to the disposal of treatment residuals. These
requirements will be met.
Discharge of treated groundwater to surface waters is regulated by
the Clean Water Act Section 402, 40 CFR 122 and 125, Subchapter N,
National Pollution Discharge Elimination System (NPDES) which regulates
point discharges to navigable waters. The Clean Water Act is administered
by MDNR under Michigan Act 245. NPDES requirements apply to discharges to
the Bame-Huntly drain. Treated waters will be discharged at levels which
permit requirements.
r
The Clean Air Act, 40 CFR 50 and 52, implements and sets rules for the
regional air pollution control program and establishes Ambient Air Quality
Standards. The program is administered by the MDNR under Michigan Act
348. These requirements are applicable to air emissions generated during
treatment of groundwater. Emissions during operation of the air stripper
will be monitored and controlled to comply with Federal PSD regulations,
Federal NSPS and NESHAP standards, and permitting requirements.
C. Cost Effectiveness
Total cost for the selected remedy is $3,024,100. The soil
flushing alternative for treatment of contaminated soil is $163,000 and
the treatment of on-site and off-site contaminated groundwater is
$2,888,100. This remedy provides the best overall effectiveness
conmensurate with costs such that it represents the most reasonable value
for the money.
A discussion comparing other alternatives considered for treatment of
on-site soil contamination follows below:
Aeration $ 515,000
RCRA Cap 1,003,000
Excavation and 21,105,000
Incineration
Costs for the RCRA cap are one order of magnitude greater than the
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29
lected remedy and offer less protectiveness. Incineration is two orders
magnitude greater than the .preferred remedy and offers no increase in
protectiveness. The cost differential between aeration and soil flushing
is a factor of two with no increase in protectiveness for the aeration
alternative.
Costs for collection of groundwater for on-site and off-site
control of migration are the same for each of the treatment alternatives.
Costs vary according to the treatment applied, the method of disposal, and
the volume of treated groundwater. No advantage in protectiveness results
from disposal at the POIW over discharge to surface waters. Both methods
of disposal meet NFDES permit requirements for discharge to surface
waters. The groundwater is treated to meet 10~6 risk levels providing
protectiveness to meet or exceed drirJcing water standards. Treatment
costs for contaminated groundwater are compared below:
Mr stripping $ 2,888,100
Steam stripping 8,321,600
Carbon adsorption 5,714,300
D. Utilize Permanent. Solutions and Alternative Technologies
The selected remedy provides a permanent solution employing alter-
native treatment or resource recovery technologies to the maximum extent
eticable and provides the best balance among the nine evaluation
eria of all the alternatives examined. The remedy is the most
opriate solution for the site. The in-situ soil treatment alternative
satisfies the preference for a permanent solution, alternative treatment
technology, and attains ARARs. The soil flushing alternative demonstrates
an advantage over the aeration alternative because of site conditions
which may reduce the effectiveness of the aeration alternative.
Design efficiencies for each of the treatment alternatives will meet
surface discharge permit requirements. Air stripping affords overall
effectiveness equal to the steam stripping and carbon adsorption
alternatives and is the most cost effective.
Groundwater treatment alternatives also satisfy the preference for
permanent solutions and alternative technology and attain ARARs. The air
stripping alternative is the most cost effective. The remedy satisfies
the preference for treatment that addresses the principal threats posed by
the site.
E. Reduction of Tbxicity, Mobility or Volume
Toxicity of contaminants in the on-site soil will be reduced through
treatment. The soil flushing alternative reduces the potential for off-
site movement of the contaminants from soil by treating the soil and the
flushing fluids. Groundwater treatment through pump and treat
•alternatives reduces the contamination of groundwater under the site and
Pontrols migration of the off-site plume.
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