r* r^
*l PflO^°
HAZARDOUS
SITE cortftrof
DIVISION
Remedial
Planning/
Field
Investigation
Team
(REM/FIT)
ZONE II
VOLUME II
APPENDIXES
FEASIBILITY
STUDY FOR
SUBSURFACE CLEANUP
WESTERN PROCESSING
KENT, WASHINGTON
EPA 37.0L16.2
March 6, 1985
CONTRACT NO.
68-01-6692
CH2MBHH1
Ecology&
Environment
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VOLUME II
APPENDIXES
FEASIBILITY
STUDY FOR
SUBSURFACE CLEANUP
WESTERN PROCESSING
KENT, WASHINGTON
EPA 37.0L16.2
March 6, 1985
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W60816.F5
EWB
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PREFACE
This volume of the Western Processing Subsurface Cleanup
Feasibility Study contains Appendixes A through G. Volume I
contains Chapters 1 through 7, and an Executive Summary is
bound separately.
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CONTENTS
Appendix A.
Appendix B.
Appendix C.
Appendix D.
Appendix E.
Appendix F.
Appendix G.
PRP Remedial Action Plan Development
Process (Prepared by PRP Group)
Summary of Applicable Regulations
Detected Indicator Compounds in Soils
and Groundwater
Environmental Migration and Fate of
Indicator Chemicals
Estimating Lifetime Average Water and
Soil Intake
Methods, Assumptions, and Criteria for
Contaminant Source Quantification,
Groundwater Quality Analysis, Battelle
Groundwater Flow/Transport Model
Methods, Assumptions, and Criteria for
Groundwater Treatment Process Selection/
Design
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Appendix A: PRP Remedial Action Plan
Development Process
(Prepared by PRP Group)
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APPENDIX A
PRP REMEDIAL ACTION PLAN
This appendix is divided into two parts. Part I, the PRP Remedial
Action Plan Development Process, describes the alternative evaluation
criteria and process that led to the selection of the PRP remedial
action plan included in this feasibility study as example alternative 4.
Part II provides background information on the analyses of contaminant
concentrations and the evaluation of contaminant excavation and ground-
water extraction effectiveness performed as part of PRP remedial action
plan development process.
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PART I
PEP REMEDIAL ACTION PLAN DEVELOPMENT PROCESS
INTRODUCTION
The PRP remedial action plan for the Western Processing site was developed
by the consulting engineering firms of Landau Associates and Dames &
Moore. The plan is based on these consultants' understanding of the
distribution of contamination at the site, the surface water hydrology and
biology, the groundwater hydrology, the geology and soil conditions, and
the prevailing and likely future land and water uses in the site vicinity.
Using contamination data obtained from the federal and state governments
and from a review of historical site operations to form this
understanding, the consultants examined alternative programs and tech-
nologies for subsurface cleanup. The basic aspect of the consultants'
understanding of onsite and site vicinity conditions are outlined in Table
1.
ALTERNATIVES EVALUATION CRITERIA AND PROCESS
The following sections described the alternatives review and evaluation
process and explain how the PRP plan was developed. The alternative eva-
luation process followed by the consultants included the following steps:
1. Potential alternative cleanup schemes and technologies were iden-
tified and evaluated (some sequentially, others concurrently.)
TABLE 1
CONDITIONS AT AND IN THE VICINITY OF WESTERN PROCESSINGC1)
Condition Interpretation
I. Contamination Distribution Computer run analyses of contaminant
In Soil depth profiles provided evidence of
significant contamination in the
deepest samples from many onsite
borings and a pattern of increasing
concentrations of individual con-
taminants with depth in many borings.
The largest quantities of heavy metals
appear to be present in the northern
half of the site, with larger quan-
tities of organics present in the
southern half of the site.
II. Contamination Distribution In general, organics concentrations are
In Groundwater higher in groundwater beneath the site
iBased primarily on EPA data (EPA 1983).
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III. Subsurface Soil and
Geological Conditions
IV. Groundwater Hydrology
V. Surface Water Hydrology
VI. Surface and Groundwater Use
than in soil beneath the site. The
reverse is generally true for metals.
Subsurface soil at the site exhibits
highly varying permeabilities, ranging
from the low permeabilities of clay and
silt to the relatively high per-
meabilities of the granular soil. No
continuous low permeability layer is
known to be present beneath the site at
shallow to moderate depths (15 to 100
feet); a low permeability layer is
known to be present to the east and
south of the Western Processing site at
a depth of between 150 to 200 feet and
is inferred to be present beneath the
site.
Groundwater mounding is present at the
site.
Regional groundwater flow is to the
west and north at a rate of about 100
feet per year.
The region is characterized by a two
aquifer system; a lower, artesian
aquifer and an upper, water table
aquifer. The piezometric surface of
the lower aquifer is substantially
higher than that of the upper aquifer
at the eastern margin of the Kent
Valley; this condition is inferred to
extend to the Western Processing site
area.
Groundwater flow in the vicinity of the
Western Processing site is primarily to
the west-northwest. Mill Creek is nor-
mally a discharge point for groundwater
in the immediate vicinity of the site;
during periods of high flow, the creek
probably discharges to the groundwater
system.
Mill Creek flows vary widely but are
probably less than about 10 cfs in the
summer. EPA measurements in May 1982
indicated that the creek flow increased
by about 10 percent from groundwater
contribution in the reach adjacent to
the site.
The rivers and tributary streams in the
Kent Valley support spawning runs of
A-2
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anadromous trout and salmon species.
The Green River is used for
recreational fishing; it is also a
discharge point for treated industrial
waste water.
Drinking and agricultural water
supplies are drawn from the lower,
artesian aquifer. The City of Kent has
installed three new wells into the
lower aquifer approximately 1 1/4
miles upgradient from the Western
Processing site. The planned future
pumping from these wells is not
expected to cause drawdown in the lower
aquifer beneath the site; therefore,
the pumping would not draw contaminants
in the upper aquifer into the lower
aquifer.
The upper aquifer is not presently
known to be used as either a public or
private water supply in the site vici-
nity; it is not likely to be used for
water supply in the future because of
the abundance of cleaner water in the
lower aquifer and from other sources.
Multiple non-point sources of con-
tamination are present in the Kent
Valley and are contributing to the
degradation of water quality in the
upper aquifer.
VII. Land Use Tne Kent Valley in the Western
Processing site area has changed from
an agricultural to a commercial/light
industrial area over the past 20
years. Tnis use is projected to con-
tinue for the foreseeable future.
A-3
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2. Alternative technologies under each scheme were evaluated and com-
pared in terms of the following screening criteria:
a. technical feasibility
b. previous use
c. reliability
d. potential for public acceptance
e. future productive site use
f. installation time
g. future liability for PRPs
3. The most favorable alternative cleanup scheme that resulted from
the screening process was evaluated in terms of its capability to
eliminate the potential for harm at identified receptors. Because
the upper aquifer in the site vicinity is not used as a source of
municipal or private water supply for human or other uses, and is
not likely to be useable for human consumption without treatment,
the receptors of concern were identified as Mill Creek and the
Green River. Because these two receptors are not sources of water
for human consumption, the consultants focused on the potential
for harm to aquatic organisms as the measure of impact.
Freshwater aquatic water quality criteria were identified for com-
parison to projected and predicted contaminant levels at the
receptors. Two-dimensional contaminant transport modeling was
performed to evaluate contaminant concentrations at the Green
River following completion of the cleanup scheme. A "no action"
scheme was also modeled for comparison.
The computer modeling indicated that the most favorable alternative scheme
would reduce contaminant concentrations to acceptable levels in Mill Creek
and the Green River; the most favorable alternative was therefore adopted
as the PRP remedial action plan. Refinements to the plan were subsequently
made following review by the PRPs and during the development of design
specifications for the plan.
POTENTIAL CLEANUP SCHEMES
Following the consultants' review of available hydrological and hydro-
geological information on the Kent Valley and the EPA report
"Investigation of Soil and Water Contamination at Western Processing, King
County, Washington, September to November; 1982" (EPA 1983), potential
cleanup schemes were identified. As indicated below, the general cate-
gories of potential cleanup schemes consisted of containment or removal of
the contaminated material, although only the removal option was considered
for Mill Creek.
1. Containment - surrounding the contaminated onsite materials and
soil with an impermeable barrier or chemically stabilizing the
contaminated materials.
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2. Removal - removal of contaminated onsite materials and soil by
excavation or other means, removal and treatment of contaminated
groundwater.
3. Mill Creek cleanup - removal of contaminated sediments.
ALTERNATIVES ANALYSIS
For each of the potential cleanup schemes there were several alternative
technologies that could be employed to provide the identified type of
cleanup. A list of these alternatives is provided in Table 2.
The alternative technologies evaluated for each potential cleanup scheme
and the major advantages and disadvantages of each alternative are
described in the following subsections. An evaluation of the alternatives
in terms of the previously identified screening criteria is provided in
Table 3.
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Table 3
EVALUATION SUMMARY
POTENTIAL CLEANUP SCHEMES AND ALTERNATIVE TECHNOLOGIES
WESTERN PROCESSING SITE
Technical
Feasibility Previous Use
A. Containment
1. Impermeable cap Not feasible Cutoff walls
and cutoff wall at Western and impermeable
Processing caps have had
because of widespread ap-
lack of con- plication and
tinuous imper- demonstrated
meable success in re-
stratum ducing or elim-
inating ground
and surface
water flow into
and out of a
site
2. PCRA landfill Feasible Demonstrated
technology
Potential
Installation for Public
Reliability Time Acceptance
High contaminant Could be in- Evaluated to
concentrations stalled in be low because
and pH range less than one all contami-
could reduce year nated material
long-term effec- remains on-
tiveness of cut- site, with
off wall potential for
eventual es-
cape if cutoff
wall fails
Assumed to have May require Evaluated to
reasonable more than one be low because
reliability year to all contami-
install nated material
remains on
site; public
distrust of
landfill
technology
Future
Site Use
Site would re-
main hazardous
waste disposal
site and not
be available
for future
use
Site would re-
main a RCRA
hazardous
waste site and
not be avail-
able for
future use
Liability
for PRPs
Site would
require main-
tenance and
monitoring for
at least
30 years as
required under
RCRA. Long-
term potential
for liability
associated
with cover de-
generation and
cutoff wall
failure
Site would
require main-
tenance and
monitoring for
at least
30 years as
required by
RCRA. Long-
term liability
associated
with necessity
to repair
and/or replace
liners
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Technical
Feasibility
3. Stabilization Questionable
feasibility,
given range of
contamination
chemistry and
concentrations
and pH range
B. Removal
1. Excavation of Feasible; ex-
contaminated tensive dewa-
material and tering and
soil to a spe- large volume
cific concen- water treat-
tration level ment required
for probable
concentration
cutoff levels
Table 3
(continued)
Installation
Previous Use Reliability Time
Not previously If successful Likely to re-
used at site stabilization quire more
with comparable product is iden- than one year
chemical tified through to install
complexity testing, would
be considered to
have good long-
term reliability
Extensive pre- High reliability Could be ac-
vious use in terms of complished in
source removal; less than one
does not address year
contaminant in
groundwater
beneath site
Potential
for Public Future
Acceptance Site Use
Evaluated to Site would re-
be low because main a RCRA
site remains a hazardous
hazardous waste site and
waste site not be avail-
under RCRA able for
future use
High potential Unrestricted
for public ac- future use
ceptance, pro-
vided that the
cutoff level
selected re-
duces receptor
impacts to
nonharmful
levels
Liability
for PRPs
Site would
require main-
tenance and
monitoring for
at least
30 years under
RCRA. Lowest
potential
long-term lia-
bility from a
technical
standpoint of
the contain-
ment
alternatives
Potential
long-term lia-
bility because
groundwater
contamination
is not
addressed
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Table 3
(continued)
Technical
Feasibility Previous Use
2. Excavation of Technically Each component
fill and hot feasible previously
spots; cutoff used; limited
wall; ground- use of all
water pumping three in
combination
C. Hill Creek Cleanup
1. Sediment re- Technically Commonly used
moval only feasible; sim- for contaminant
plest cleanup removal
alternative
2. Sediment re- Feasible Not as commonly
moval with used as sedi-
creek liner ment removal
Reliability
Because alterna-
tive removes all
mobile contami-
nants, long-term
reliability is
good
Combined with
the onsite
cleanup plan,
sediment removal
will allow Mill
Creek water
quality to
recover
Liner could de-
teriorate with
time
Potential
Installation for Public
Time Acceptance
Can be in- Good, because
stalled in receptor im-
one year, pacts reduced
with ground- to nonharmful
water removal levels
for several
additional
years
Of the three Should be
alternatives, acceptable to
sediment re- the public
moval only
requires the
shortest
installation
time
Requires more Should be
time for in- acceptable
stallation
than removal
only, but
less time
than creek
diversion
Future Liability
Site Use for PRPs
Site available No long-term
for some fu- liability for
ture produc- site mainte-
tive uses nance or sys-
tems failures
NA Because the
contamination
is removed, no
long-term
liability is
associated
with this
alternative
NA Potential
requirement
for liner
maintenance
activities
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3. Creek diversion
Technical
Feasibility Previous Use
Feasible but Not as commonly
more difficult used as sedi-
than sediment ment removal
removal only
Table 3
(continued)
Installation
Reliability Time
Reliable Would require
longer to in-
stall than
other two
alternatives.
Long poten-
tial delays
associated
with need to
obtain prop-
erty or ease-
ments for new
creek bed
Potential
for Public Future
Acceptance Site Use
Should be ac- NA
ceptable, with
the possible
exception of
landowners on
whose property
the new creek
bed would be
constructed
Liability
for PRPs
No long-term
liability
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Containment Scheme
As identified in Table 2, three containment technologies — enclosing the
contaminated materials in place so that future contaminant releases are
prevented — were evaluated: (1) enclosing the site with a cutoff wall and
copaivering the site with an impervious cap, (2) confining the contaminated
materials within a RCRA landfill, and (3) chemically solidifying the
contaminated materials.
Impervious Cap with Cutoff Wall
To completely enclose the contaminated materials by means of an impervious
cap and cutoff wall, a low permeability soil or rock layer must be present
continuously beneath the site to be enclosed. When such a low
permeability layer or stratum is present, the cutoff wall can be tied in
to this stratum, thereby forming a subsurface "vault." With the cutoff
wall and an impermeable cap in place, neither surface water nor
surrounding groundwater will flow into and through the contaminated
materials. With no water flow through the site, mobile contaminants in
the soil and contaminants in the groundwater beneath the site would have
no means of offsite transport except by diffusion (a slow process that is
very minor relative to groundwater flow).
Cutoff walls have been used extensively to stop the flow of groundwater
into excavation sites, to divert groundwater flow around a site, and to
prevent migration of water or liquid wastes through dikes or out of
impoundments. More recently they have been used at hazardous waste sites
to divert groundwater flow around a site and/or to prevent the migration
of leachate from a contaminated site. Thus, the technology is well
demonstrated in terms of its capability to block the flow of water or
certain liquid waste materials. However, the long term effectiveness of a
cutoff wall to block groundwater flow and prevent the migration of
contaminants at hazardous waste or Superfund sites has not been
demonstrated. Materials evaluated for the cutoff wall included sheet
piling, concrete, cement/bentonite, soil/bentonite, asphalt, and a
synthetic membrane.
The use of impervious caps or covers to reduce or eliminate rainfall
infiltration is a proven, reliable technology. An asphaltic concrete
cover was contemplated under this scheme.
Although this type of scheme is feasible in concept, it was rejected for
the Western Processing site because the data supplied by EPA in their 1983
report did not confirm the presence of a continuous low permeability layer
at a reasonable depth beneath the site. With no such layer to serve as
the bottom of the vault, this scheme was not viable for the Western
Processing site.
In addition to the above consideration, the consultants were concerned
about the long term reliability of the cutoff wall, given the nature of
the chemical contamination and pH conditions beneath the site. No
previous use of a cutoff wall at a site with a similar large number of
contaminants (both metals and organics) and high contaminant
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concentrations, plus both low and high pH conditions, was identified.
There was considerable doubt regarding whether, over the long term, any
type of cutoff wall could maintain the desired level of impermeability (at
least 1x10 on/sec.) while continuously exposed to these conditions.
Because the contaminated materials would remain onsite, this alternative
would be regulated as a RCRA disposal site. Therefore, productive future
use of the land would be precluded.
Onsite RCRA Landfill
At the same time the impervious cap/cutoff wall scheme was being
investigated, the consultants also were evaluating the possibility of
enclosing the contaminated materials in an onsite landfill designed to
RCRA specifications (40 CFR 264). Use of this technology would involve
excavating the contaminated material and soil and stockpiling them on the
site; this would be followed by the construction of a clay base, a
synthetic liner, and a leachate collection system. The contaminated
material would then be placed in the lined excavation. An impervious cap
consisting of a clay base, synthetic liner, drainage layer, and topsoil
layer would then be constructed over the top of the contaminated material.
The contaminated material would, by this means, be completely enclosed and
isolated fron contact by surface water or groundwater. Excess moisture
present in the contaminated material when placed in the lined excavation
would slowly migrate to the bottom of the landfill and be collected in the
leachate collection system. No contaminant migration from the site would
occur.
Because the landfill design selected was that mandated under RCRA, the
landfill technology was deemed to be a technically feasible, previously
used, and reliable alternative for use at the Western Processing Site.
Technical difficulties that would have to be addressed included the
necessity of constructing the landfill in stages, so that the excavated
contaminated material could be stockpiled onsite before being replaced in
the lined excavation. Because the bottom of the landfill would need to be
above the seasonal high groundwater table, which is close to the land
surface, much of the landfill would have to be constructed as an above-
ground mound.
Like the encapsulation alternative, the RCRA landfill alternative would
leave the site as a permanent hazardous waste disposal facility,
eliminating productive future use of the site. As such, the site would
also remain a potential long-term liability to the PRPs.
Stabilization
Under this alternative, onsite contaminated material would be excavated,
mixed with a material that would immobilize (stabilize) the contaminants,
and replaced in the excavation. The site would then be capped with an
asphaltic concrete cover. Portland cement, asphalt-based lime, fly ash,
gypsum, and polymer stabilization agents were evaluated.
This alternative, like the other containment alternatives, had the
advantage of eliminating the risks and costs associated with transporting
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and disposing of the contaminated material at an offsite hazardous waste
facility. Under some stabilization methods, the cost of stabilization was
considerably less than the cost of offsite transportation and disposal on
the basis of vendor cost estimates. However, stabilization was rejected
for the following reasons:
1. Oily one of the stabilization methods, cement, had been demonstrated
at a site with the chemical complexity of the Western Processing
site. This stabilization method can be very costly. The time
required to develop and test suitable formulae for other potential
stabilizers would be lengthy, with no guarantee that a successful
product—one with a high probability of long-term effective
operation—could be developed.
2. While some of the stabilization methods (e.g., lime and fly ash)
were relatively inexpensive, compared to the cost of offsite
transportation and disposal, others were more expensive. The less
expensive methods were evaluated to have a lower probability of
effective, long-term binding of all of the chemical contaminants at
the Western Processing site.
3. Where chemical stabilization has been or is proposed for use at
other hazardous waste sites around the country, the EPA is requiring
that the sites be considered RCRA landfills. Thus, the
stabilization alternative would involve all of the components and
costs of the RCRA landfill alternative plus the difficulties,
uncertainties, and cost of chemical stabilization. Although these
two technologies combined would result in a state-of-the-art
containment scheme with a high probability of successfully
containing contaminants on the site over the long term, the site
would still be left as a hazardous waste disposal site and hence not
available for productive use. As such, the site would be a long-
term potential liability for the PRPs.
Removal Schemes
Two types of removal schemes were evaluated for the Western Processing site:
excavation of contaminated soil to depths defined by a selected contaminant
concentration "cutoff" level, and excavation of probable buried waste
locations combined with a program to remove contaminated groundwater and
flush mobile contaminants from unexcavated soil. Removal schemes are
normally focused on removing a specified amount of the contaminants present
at a site. A decision regarding how much needs to be removed is made on the
basis of regulatory requirements or guidelines and the potential for harm to
humans and the environment. Normally the contaminated material is taken to
a hazardous waste facility for disposal by landfilling.
At the Western Processing site, the EPA's onsite data indicated that
contaminants had migrated to at least 30 feet below ground surface. A
number of individual contaminant concentrations showed a pattern of increase
with depth in onsite borings, suggesting that high concentrations could be
expected in soil below 15 feet. However, any excavation at the site deeper
than 8 to 10 feet below the ground surface during the drier summer season
would encounter groundwater. During the wet winter season, groundwater
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would be encountered at shallower depths. Excavating to depths below the
groundwater table would require dewatering of the excavations and
consequently slower construction techniques. Most significantly, the
groundwater that would have to be removed to dewater the excavations would
be contaminated and would have to be either treated prior to discharge or
transported to a hazardous waste facility.
Analysis of the data developed by EPA on the distribution of contaminants in
surface and subsurface soils had indicated that there was no clear pattern
of contaminant distribution on which to base a removal scheme, other than
that the majority of metals contaminants were in the soil while the majority
of organics were in the groundwater.
Excavation to Contaminant Cutoff Level
The contaminant cutoff scheme initially evaluated for the Western Processing
site focused on levels of metals in the soil. The consultants evaluated
removal schemes that involved excavation to two cutoff levels: 5000 ppm and
2000 ppm of total priority pollutant metals. The following table shows the
amount of contaminated material that would need to be excavated, and the
maximum depth of the excavation, for these contaminant cutoff levels:
Total Priority Pollutant Volume of Maximum Depth
Contaminant Level (ppm) Excavation (cu.yds) of Excavation
5,000 105,000 11 feet
2,000 145,000 13 feet
As can be seen, these alternatives would involve the removal of very large
quantities of material that would subsequently have to be shipped to a
hazardous waste facility for disposal. Moreover, the excavations would
extend below the groundwater table. Thus, large quantities of water would
have to be pumped (and subsequently treated or shipped to a hazardous waste
facility) in order to dewater the excavations.
Furthermore, the contaminant cutoff levels were chosen somewhat
arbitrarily—there are no guidelines that specify acceptable residual
contamination levels for Superfund sites. At the time, the Washington
Department of Ecology's policy for cleanup of soil contamination was to
clean a site to levels no higher than 10 times the water quality criterion
for the contaminant in question, or to a background level established by
measuring soil samples that were representative of the site area. Despite
the large quantities and depths that would be involved in the previously
cited options, none would have satisfied the DOE policy.
Excavation of Waste Materials Combined with a Pumping/Flushing Scheme
At the same time that the depth/concentration questions were being
evaluated, pumping and treatment of contaminated groundwater were also being
evaluated. Because most of the organics (by mass) were present in the
groundwater, according to EPA's data, no program of soil removal alone would
remove these contaminants from the site. Therefore, groundwater pumping was
deemed necessary to remove the organics from beneath the site.
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Groundwater removal can be accomplished by three general methods: gravity
collection (drains), vacuum pumping (well point system), or positive
displacement (individual wells with submerged pumps). Which method or
combination of methods is appropriate for a particular site depends on the
objectives for the installation and performance of the system. For the
Vfestern Processing site, the following objectives are applicable to the
groundwater removal system.
a. The method selected should, in conjunction with other components of
the cleanup plan, minimize the quantity of groundwater pumped.
b. It should be reliable and easily serviceable.
c. It should be flexible and adaptable.
d. It should allow groundwater samples to be collected conveniently.
e. It should be cost-effective to install and maintain.
Gravity collection satisfies several of these objectives, but would be
unable to withdraw contaminated groundwater below a depth of about 15 feet.
Gravity collection would, however, be effective in eliminating the
groundwater mound present at the site.
A well point system satisfies all of the above objectives. It would be
particularly effective in minimizing the quantity of groundwater pumped.
Such a system is adaptable, reliable, and conveniently serviceable. The
system can be designed so that individual well points can be sampled at
various locations on the site. Because of the large number of well points
that would be installed, clogging or other failure of a few of the well
points would not adversely affect the performance of the system. The ease
of installation and low individual cost allow uncomplicated and inexpensive
replacement if necessary.
The well point system would be particularly useful for identifying the
effectiveness of the pumping in all areas of the site. Individual well
points or sections of the system could be closed off to allow selective
recovery from specific portions of the site if necessary to optimize the
recovery of contamination remaining after soil removal.
Deeper wells with submerged pumps also satisfy most of the above criteria,
but less effectively than the well point system. Because of the cost of an
individual well installation and the greater drawdown afforded by each
individual well, the number of wells installed would be considerably less
than for the well point system; the deep well system would, therefore, be
less flexible and adaptable. The failure of an individual deep well would
have a greater impact on the overall performance of the system, and the cost
of service and replacement would be greater than for the well point system.
As the consultants considered the technical aspects of groundwater removal
as well as the infeasibility of excavating enough soil from the site to
remove the majority of contamination in the soil, they realized that they
could also use the groundwater removal system to remove mobile contaminants
frcm the soil by a soil flushing process. This involves removing the
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contaminated groundwater from beneath the site and then drawing cleaner
water frcm outside the site through the contaminated soil. As this cleaner
water passes through the soil, it will remove the mobile contaminants that
had been leached by infiltrating rainwater fron the surface or from buried
wastes and had subsequently become physically or chemically bound to the
soil particles. This soil flushing process would partially reverse the
mechanism which conveyed the contaminants to their present location within
the soil profile.
To maximize the depth of contaminated soil through which the cleaner water
would be drawn, the consultants determined that construction of a "hanging"
cutoff wall would be useful. Unlike the cutoff wall contemplated under the
containment scheme, this cutoff wall would be constructed only to a depth
equal to or slightly greater than the depth at which contaminants were still
found in relatively high concentrations. Because the contaminated
groundwater would be withdrawn from beneath the site in a relatively short
period of time, the cutoff wall would not be subjected to the same degree of
chemical attack that was of concern to the containment scheme. Further, the
wall would only need to maintain a very low permeability for the duration of
the limited pumping/flushing period.
In the absence of definitive data on the depths to which high concentrations
of contaminants occur on the site, a depth of 40 feet was selected for the
hanging cutoff wall. While there is evidence suggesting that the high
concentrations decrease between 25 and 30 feet below the ground surface, a
40-foot depth was chosen to be conservative.
The decision to use a groundwater removal system to also remove mobile
contaminants from contaminated soil at the site made the well point system
the definitely preferable alternative for groundwater removal. In
addition, the consultants determined that, for the reverse leaching scheme
to work at the Western Processing site, very high concentrations of
contaminants and all buried wastes would have to be removed. This is
because any contamination that had entered the subsurface by a means other
than leaching would not be amenable to removal by the reverse leaching or
soil flushing process. Thus, an excavation plan that would complement the
groundwater pumping/soil flushing plan was developed concurrently.
This excavation plan involves the excavation of all fill areas on the site
to the original ground contours prior to the first use of the site as an
anti-aircraft artillery (AAA) installation. Aerial photographs of the site
over the years frcm 1946 to 1982 showed continuous excavation and filling
operations. It was reasoned that fill areas, whether natural depressions or
excavations, would be the most likely location of buried materials. The
excavation plan also included removal of "hot spots"—areas of significantly
higher contaminant concentrations—identified on the basis of EPA's data.
Mill Creek Cleanup
Measures to clean up Mill Creek were deemed appropriate due to relatively
high concentrations of contaminants in sediments in the creek adjacent to
and downstream of the Western Processing site. Three cleanup alternatives
were evaluated: sediment removal only, sediment removal in conjunction with
placement of a synthetic bottom liner, and sediment removal associated with
A-15
-------
permanent creek diversion. All three alternatives involve diversion of the
creek, although diversion in the first two alternatives is temporary. Mill
Creek cleanup is essentially independent of the technologies for onsite
contaminant containment or removal; it was thus evaluated separately.
Sediment removal only was selected because of its cost effectiveness and
relative ease and feasibility of construction. It can be accomplished
independently of the onsite work. Because this method requires temporary
diversion of Mill Creek, it is best implemented during the summer to
minimize the need to divert high flows and handle precipitation into and
runoff from the cleanup area. Permits to divert the flow and cross private
and public property with the diversion pipeline would be necessary for this
as well as the other alternatives.
Addition of a liner after sediment removal would reduce the amount of
residual contamination entering Mill Creek via groundwater. However, after
the onsite remedial activities are implemented, the transport of
contamination to the creek by groundwater will be significantly reduced.
Therefore, only a small amount of residual contamination would enter Mill
Creek, if unlined; this contamination would remain in the groundwater if a
liner is placed in the creek. For these reasons, placement of the liner is
not deemed appropriate.
Permanent creek diversion (rerouting) could potentially eliminate residual
contamination entering the creek. However, the reasons for rejecting the
liner alternative are the same as for rejecting the permanent diversion
alternative. Additionally, permanent diversion would require obtaining
easements or rights-of-way or acquisitions of property; it might also
interfere with the City of Kent's plans to modify the Mill Creek system to
improve storm water drainage in the Kent Valley. While it would obviously
be desirable to coordinate permanent diversion of the creek with the
drainage system improvements, plans for the latter have not been developed
and will not be until after implementation of the remedial action plan.
Thus, permanent diversion during cleanup is unwise frcm a long-range
planning standpoint as well as being unwarranted technically.
A-16
-------
PART II - BACKGROUND INFORMATION
ON STUDIES PERFORMED AS PART OF THE PRP
REMEDIAL ACTION PLAN DEVELOPMENT PROCESS
The studies described in the following sections were based on con-
taminent data developed by the USEPA and published in May 1983 in the
two part document entitled "Investigation of Soil and Water
Contamination at Western Processing, King County, Washington."
Subsequent investigations conducted by USEPA have produced additional
contaminant data; these data are not reflected in the following
discussions. In addition, at the time these studies were performed, the
degree of influence exerted by Mill Creek on local groundwater flow pat-
terns was not known; subsequent ongoing studies are refining the results
of the effectiveness analyses performed to evaluate the PRP plan to take
into account this new information regarding Mill Creek's effect on local
groundwater flow.
The studies described in this part are the following:
1. The method of calculating onsite average contaminant con-
centrations in soil and groundwater.
2. The contaminant ranking procedure.
3. Post-excavation soil concentrations.
4. Flushing program effectiveness evaluation.
ONSITE AVERAGE CONTAMINANT CONCENTRATIONS
Need for Average Concentrations
The data for soil and groundwater contaminant concentrations at
the Western Processing site reported in the USEPA May 1983 report
reflect large quantitative variations among different samples. These
are demonstrated in highly skewed frequency distributions of con-
centrations for most of the measured contaminants. Analyses based only
on maximum concentrations would not reflect this distribution of con-
A-17
-------
taminant concentrations; some measure of typical concentrations at the
site for both soil and groundwater contaminants was desirable in order
to supplement the analyses based on maximum concentrations alone.
The variation of contaminant concentrations in samples from dif-
ferent onsite locations diminishes in importance with increasing
distance from the site. A variety of physical and chemical processes
act to "average" the disparate concentrations, reducing the variability
characteristic of individual measured concentrations. A calculation of
onsite average concentrations may be used as a first approximation of
this phenomenon. Moreover, information on the average concentrations by
contaminant in soil and groundwater provides data helpful for selecting
appropriate parameters for groundwater modeling for use in evaluating
the effectiveness of a remedial action. Such modeling still may account
for the geographic variability in contaminant concentrations across the
site. However, parameter values determined using the data for onsite
average concentrations incorporate site conditions (e.g., soil types)
and thereby supplement parameters derived from theory alone and improve
modeling predictions.
General Approach
A weighting factor approach, with the sum of the weights equal to
one, was used to calculate a single average concentration from the
multiple onsite sample values for each contaminant.1 Considerations of
geographic proximity and past activities and uses of the site led to the
development of two different sets of weights. The first was based on a
geometric partitioning of the site into contiguous areas surrounding
each available sampling location. The values at a sampling location
were assumed to be representative of the area defined around it, and the
appropriate weight therefore became the proportional site area included
in the partitioned cell surrounding the sample location. This method
accounted for the assumed proximity relationship (nearby locations
should have more similar pollutant concentrations than distant loca-
tions, on average); however, the partitioned cells often included only a
The average value of contamination C is calculated by the formula Cave.
= iW-j^C^, where W^ is the weight for well number i and C^ is the con-
centration of contaminant C at well number i.
A-18
-------
part of an area of significant site use (e.g., surface impoundment) or
included multiple site uses, and therefore do not reflect appropriately
the influence of site history.
A second approach used information on past site activities and uses
to derive a set of weights. Rather than assigning a single
(area-derived) weight to each sampling location directly, the site
history approach focused on identifying distinct subareas of the site
used for surface impoundments, waste piles, tanks, or other significant
uses. A set of one or more sampling locations deemed representative of
each subarea was identified, based on the correspondence of site history
for the subarea and sampling locations. The proportional area of each
site-history derived cell was then allocated equally to each of the
representative sampling locations. For example, the reaction pond area
constituted approximately 6.95 percent of the total site area. Wells
10, 14, and 16 were deemed representative of this impoundment area; each
was allocated a weight equal to one-third of the reaction pond's propor-
tional area, or 0.0695 divided by 3 equals 0.0232. A single sampling
location could be representative of more than one site use subarea;
in such cases, the final weight assigned to that sampling location was
the sum of its partial weights.
In most instances, the set of representative sampling locations
consisted of adjacent or nearby wells, preserving the assumed proximity
relationship even though assigning weights somewhat differently. In a
few cases, however, no nearby wells represented similar site used; in
these cases, the representative sampling locations used were from more
distant portions of the site. Given the available sampling locations,
both site history and proximity relationships could not be preserved in
all cases.
The weights resulting from these two approaches showed considerable
differences. However, the onsite average concentrations calculated for
each contaminant using these two sets of weights are generally similar,
differing most significantly for a few contaminants detected only at low
concentrations or at only a few locations. The calculated average con-
taminant concentrations, along with maximum concentrations, are listed
in Table A-1.
A-19
-------
TABLE A-1
MAXIMUM AND AVERAGE CONTAMINANT CONCENTRATIONS IN ONSITE SOIL
-------
TABLE A-1, continued
Maximum Concentration^1
Contaminant
2, 4-Dichlorophenol
2, 4-Dimethylphenol
Phenol
Aldrin
Dieldrin
4, 4 -DDT
4,4-DDD
Heptachlor
Lindane
PCB-1242
PCB-1254
PCB-1248
PCB-1260
PCB-1016
Acenaphthene
He xach lor oe thane
1 , 2-Dichlorobenzene
Fluoranthene
Naphthalene
Bis-2 (ethyl hexyl)
phthalathe
Benzylbutylphthalate
Benzo (a ) -anthracene
Chrysene
Anthracene
Flourene
Phenanthrene
Pyrene
Surface
0
11,000
19,000
0
145
0
0
0
34
137
3,300
2,046
2,030
0
5,090,000
0
2,200
234,000
6,200,000
860,000
884,000
1,210,000
0
8,600,000
20,000,000
16,000,000
Subsurface
Soil
7,900
10,000
65,000
2,860
3,340
129
100
2,960
11.8
1,780
407
19,600
1, 710
3,160
8, 700
1,800
565,000
7, 700
13,000
410,000
9,100
4,000
2,500
1,600
16,900
62,400
1 1,000
^ Average Concentration ^r J
Site Percent
Geometric (d ' History ^Difference ^e
208.60
218.15
1652
6.08
7.10
2.92
0.77
6.23
0.09
79.03
4.33
341.27
38.13
50.32
75.86
19.17
13,007
155.75
226.52
12,238
79.35
47.84
29.90
19.14
147.37
719.80
184.42
164.39
168.67
1210
9.58
11.19
4.12
0.84
9.82
0.10
50.51
1.89
292.32
33.25
42.31
116.75
8.35
10,780
165.88
196.88
4,635
122.12
35.28
22.05
14.11
226.80
954.30
212.89
21.2
22.7
26.8
57.6
57.6
41.1
9.1
57.6
11.1
36.1
56.4
14.3
12.8
15.9
53.9
56.4
17. 1
6.5
13.1
62.1
53.9
26.3
26.3
26.3
53.9
32.6
15.4
* ' Values in ppb.
A-21
-------
TABLE A-1, continued
Maximum Concentration (* 1
Surface
Contaminant Soil^c^
Benzene
1,1,1 -Trichloroe thane
1 , 1 -Dichloroe thane
Chloroform
Trans-1 , 2-Dichloroethene
Ethylbenzene
Methylene chloride
Flor otri chlorome thane
Tetrachloroethene
Toluene
Trichloroe thene
0
0
0
0
0
13
130
25
99
0
37
Subsurface
Soil
199.5
174,000
17.3
18,000
34
37,000
49,000
73
72,000
394,000
580,000
' Average Concentration^* '
Site Percent
Geometric (d > History (d >Dif f erence (e
1.53
2,870
0.13
143.25
0.99
523.87
1,486
3.21
1,196
6,437
19,267
1.67
2,411
0.14
155.81
0.51
570.13
1,435
1.90
976.28
6,817
17,853
9.2
16.0
7.7
8.8
48.5
8.8
3.4
40.8
18.4
5.9
7.3
Available Data
The locations of available data for soil and groundwater con-
taminant concentrations in the upper zone differ slightly. For EPA
Wells 27 and 28, which are immediately adjacent to the western boundary
of the site, groundwater data are available but no soil values were
reported.^ These wells, because of their location near the site boun-
dary, provided useful data for calculating onsite groundwater con-
centrations. Therefore, the weights for soil and groundwater averages
are slightly different, reflecting the inclusion of EPA Wells 27 and 28
in the latter case only. A total of four distinct sets of weights—
using geometric and site history approaches for both soil and ground-
water data—were derived.
Data from more distant offsite wells, including Wells 13 and 19
which provide the only offsite soils information included in the data
base of this study, were not used in the calculation of onsite average
concentrations for the upper zone.
^EPA's May 1983 report, "Investigation of Soil and Water Contamination
at Western Processing, King County, Washington," shows that a total of 5
soil samples were taken (see Part I, Table 2, p. 15) at Wells 27 and 28.
However, no data were reported for these soil samples.
A-22
-------
Limited groundwater data were available for several deeper zones at
approximately 30 to 150 feet below ground surface. Five onsite wells
(1, 11, 17, 22, and 25) provided information for the 30-foot zone; the
50- and 130-foot zones were each characterized by three offsite wells
from the set of four Wells 31 through 34. A set of weightings for each
of these deeper groundwater zones was derived using a geometric par-
titioning approach. No comparable data for deeper soil contaminant con-
centrations were available; except for Well 17, the deepest soil samples
were for 15 feet below ground surface.
Weightings Used in Calculating Average Concentrations
Soil Average Concentrations. Each onsite well provided soil contaminant
data for a series of sampling depths. For the purpose of calculating
onsite averages of contaminant concentrations in soil, this depth pro-
file information was not preserved. The concentrations within each well
were averaged and then multiplied by the appropriate weight; the sum of
these values was then used to represent the onsite average con-
centration.-^ Sixty-eight contaminants (51 priority pollutants, 8
nonpriority pollutant inorganics, 9 nonpriority pollutant organics) were
quantified in the data base for this study at concentrations above
detection limits in onsite subsurface soils.
The same weights can be used to calculate average soil con-
centrations before and after the soil removal phase of remedial actions
onsite, thus providing one measure of the effectiveness of surface
cleanup and soil removal.
Figure A-1 shows the partitioning of the site used to derive a set
of geometric weights for calculating soil averages. Table A-2 lists
both the geometric and site history weights by well location. A com-
parison of the two sets of weights in Table A-2 shows that there are
significant differences in the weights derived by the two approaches.
Groundwater Average Concentrations. Onsite groundwater average con-
centrations were calculated for the upper zone, using the data from the
limitations of available data with depth are accepted in performing
this calculation; no attempt was made to project contaminant con-
centrations for depths below the sample locations. Thus, the calcula-
tion provides an "upper-zone" average concentration in soils.
A-2 3
-------
Geometric Partitioning of
for Calculating Soil
Average Concentrations
South 196-th Street
ence
Line
0 150 300
Scale in Feet
Figure A-1
-------
26
27(b)
TABLE A-2
WEIGHTINGS FOR CALCULATING ONSITE SOIL AVERAGES
(SUBSURFACE)
Well
1
2
3
4
5
6
7
8
9
10
11
12
14
15
16
1 7
18
19
-------
uppermost screened interval in each of the wells. Since the data for
only a single sample within each well were used, no averaging of values
within the well was necessary. Each value was multiplied by the
appropriate weight; the sum of these contributions over the site repre-
sents the (upper zone) average groundwater concentration. A total of 46
priority pollutants, 8 nonpriority pollutant inorganics, and 10
nonpriority pollutants organics were quantified at concentrations above
detection limits in the groundwater data.
Figure A-2 shows the partitioning of the site used to derive a set
of geometric weights for calculating upper zone groundwater averages.
This is identified to Figure A-1 for soils, except in the vicinity of
Wells 27 and 28, located on the western boundary of the site. Table A-3
lists both the geometric and site history weights, again illustrating
that significant differences in weights result from the two approaches
to calculating onsite averages.
For deeper groundwater zones at approximately 30, 50, and 130 feet
below ground surface, only a geometric partitioning assignment of
weights was used since the available data were quite limited. Table A-4
identifies the wells and weights used for these three deeper zones to
calculate average concentrations. All of the data used in calculating
groundwater average concentrations for the deeper zones (50- and
130-foot) represent offsite sampling locations.
CONTAMINANT RANKING
Although 46 EPA priority pollutants^ were encountered in the
groundwater, including known and suspected carcinogens, there is a wide
range of contaminant concentrations and toxicities. Because of this
toxicity range and the large number of contaminants encountered, a
classification system was established to identify which contaminants
would be analyzed in detail. This "priority ranking" was determined
using a subjective analysis that included the following considerations,
listed in order of decreasing importance:
4A11 13 EPA priority pollutant metals and 33 of the EPA priority pollu-
tant compounds were found in quantifiable concentrations in groundwater.
A-26
-------
1. Diminution factor, which is the average concentration of the
contaminant in the groundwater in the upper zones of onsite
monitoring wells divided by either the human health criterion
or the aquatic criterion for that contaminant, whichever is
lower. The resulting factor indicates the ratio by which the
contaminant must be diluted or otherwise attenuated to meet
the criterion. Assuming all other issues related to con-
taminants are equal, contaminants with the highest diminution
factors are of greatest concern.
2. Average concentration of the contaminant in the onsite ground-
water.
3. Comparison of concentrations in the onsite groundwater with
background concentrations at receptors.
4. The number of wells in which the contamination was found.
5. Whether there is a water quality criterion for the specific
contaminant or only for a related compound or element.
A-27
-------
-South 196th Street
Geometric Partitioning of Site
lor Calculating Ground Water $/j
Average Concentrations
Fence
Line
Figure &-
-------
TABLE A-3
WEIGHTINGS FOR CALCULATING ONSITE UPPER ZONE
GROUNDWATER AVERAGES
Well
1A
2
3
4
5
6
7
8
9
10
11A
12
13(a)
14
15
16
17A
18
20
21
22A
23
24
25A
26
27
28
Sum of weights
Geometry
0.0195
0.0076
0.0074
0.0201
0.0065
0.0085
0.0178
0.0187
0.0167
0.0221
0.0436
0.0054
0.0532
0.0473
0.0399
0.0750
0.0653
0.0700
0.0598
0.1282
0.0759
0.0569
0.0612
0.0399
0.0261
0.0074
1.00
Weightings
Site History
0.0549
0.0169
0.0134
0.0549
0.0134
0.0134
0.0169
0.0549
0.0230
0.0174
0.0671
0.0169
—
0.0173
0.0392
0.01 74
0.0793
0. 1 1 80
0.0455
0.0441
0.0441
0.0441
0.0241
0.0840
0.0491
0.0134
0.0173
1.00
(a)Wells 13 and 19 ire off site (as are Wells 29 and 30) and do not
contribute to the
calculation of onsite
averages.
A- 29
-------
TABLE A-4
WEIGHTINGS FOR CALCULATING ONSITE
DEEPER ZONE GROUNDWATER AVERAGES CONCENTRATIONS
-------
As a result of this analysis, three categories of contaminants were
established: Priority Levels 1, 2, and 3. Detailed analyses of con-
taminant concentrations and migration were conducted for contaminants of
greatest concern, i.e., those in Priority Levels 1 and 2.
Priority Level 1 contaminants were considered to be of greatest
concern and were thus subjected to the most rigorous analyses throughout
studies. Priority Level 2 includes contaminants that are of potential
concern, but that appear to represent less of a threat than those in
Level 1. Priority Level 3 contaminants are those not expected to sig-
nificantly affect potential receptors and were not subjected to detailed
analyses. Because the diminution factors for Priority Level 3 con-
taminants are relatively low, it is expected that the remedial measures
adopted for Priority Level 1 and 2 contaminants will also be effective
for Priority Level 3 contaminants. Table A-5 lists the priority levels,
average concentrations, water quality criteria, and diminution factors
for all EPA priority pollutant metals and organics in the shallow
groundwater.
In addition, several contaminants not on the priority pollutant
list were measured in the groundwater. The following eight non-
priority pollutant metals were measured in the groundwater:
aluminum barium cobalt
iron manganese boron
vanadium tin
Since aluminum was found at such high concentrations in the groundwater
and could be a human health concern, it was included in the groundwater
contaminant ranking. Average concentrations for barium, vanadium, and
tin were below the level of concern. There are no established criteria
for cobalt or boron; therefore, a detailed analysis was not made for
them. The concentrations of iron and manganese were greater than
drinking water standards, but since these standards are based on aes-
thetic considerations rather than human health or aquatic toxicity,
these metals also were not analyzed in detail.
A-31
-------
GROUND WATER CONTAMINANT RANKING*"'
Mets 1 s
Cadmium
Aluminum"'
Hexavalent chromium
Arseni c
Human Health
Crlterle(b)
10
200 (WHD-
aesthetlcs's'
5,000 (NAS 7-day
health advisory)
50
0.0022
Freshwater
Aquatic Criteria'0'
Existing Proposed <
-------
TABLE A-5. Continued
OrganJ _c_s ( cont 1 nued )
2,4,6-Trl chlorophenot
Chloromethana
Vinyl chloride
2,4-Dlch lorophenol
Pentoch lorophanot
1,1,2-Trlchloroethane
1 , 1, 1-Trlchlcro*thene
4-Nltrophenol
2,4-Dlmethylphenol
To) Uene
1 , 2-0 1 ch 1 oro benzene
Isophorone
Ethyl benzene
Heptachlor epoxlde
BIS-2 (EM) Phthalate '
Carbon tetrachlorlde
Acenaphthy tene (PAH)
Human Health
Criteria""1
1.2
0.19
2
0.3 (taste)
30 (taste)
0.6
18,400
13.4
(strictest nltro-
phenol class)
400 (taste)
14 1 300
400
5,200
1,400
0.000278
(heptachlor )
15,000 (dl-)
0.40
0.0028 i
(301
Freshwater
Aquatic Criteria'0'
Existing Proposed""
970
11,000
no standard
70
3.2
9,400
18,000
190 (algae)
230
2,120
17, 500
763
117,000
32,000
0.0038
(heptachlor)
3
35,200
0 salt nater)
Average Diminution
Concentration Factor
In Ground «5H Avg./
Water Strictest Existing
On Slte KP Criteria)
118 9.8 x ID1
14.27 7.5 x I01
31.70 1.6 x 101
3.81 1.3 x I01
18.76 5.9 x 10°
2.47 4.1 x 10°
18,904 1.1 x 10°
125 9.3 x 10°
179 4.5 x 10"'
2 324 1.6 x 10"'
6.27 1.6 x 10'2
9.34 1.8 x 10'3
0.43 3.1 x ID"4
(none found on site) —
(none found on site)
(none found on site) ~
Prlorlty
Level Connent
3 —
3 —
3 — --
3 —
3 —
3 —
2 High concentration only at Mel 1 1
3 —
3 __
several wel Is
3 —
3 —
3 — •
3 —
3 —
3
3 ~—
-------
TABl£ A-5, Continued
Orqanlcs
Trans-1,2-
Dlchloro«thena
Methyl ene chloride
Chloroform
Tr 1 ch 1 oroethene
1, 1-Olchloroethane
Dleldrln
A 1 dr 1 n
1,2-Olchloroethane
Human Health
Criteria"5'
0.33
0.19
0.19
2.7
0.94'"'
(for 1,2 DCS)
0.000071
0.000074
0.94
Fluorotrlchloromethane 0.19
Benzene
0.66
1,1-Olchl oroethene 0.033
Phenol
Meptachlor
Cyanide
TetracM oroethene
2-Nltrophenol
300 (taste)
0.000278
200
0.8
13.4
(strictest
nltrophenol class)
Freshwater
Aquatic Criteria'0'
Existing Proposed1"1
11,600
11,000
1,240
21,900
(behavioral)
20,000
0.0019
3
20,000
11,000
5,300
11,600
2,560
0.0038
3.5 4.2
840
150 (algae)
230
Average
Concentration
In Ground
Water
On Site'8'
17,963
46,682
2,135
27,859
1,484
0.06
0.06
627
72.96
199
8.47
72,350
0.06
689
92
17,428
Diminution
Factor
«3W Avg./
Strictest Existing Priority
WQ Criteria) Level Comnent
5.4 x 105 2 High concentration only at Well 2
2.5 x 105 1
1.1 x I04 1 —
1.0 x 104 1 —
1.6 x 103 3 High concentration only at Well 1
8.5 x I02 3 Quantifiable concentration only
at Well 28
8.1 x 102 3 Quantifiable concentration only
at Well 28
6.7 x I02 3 Quantifiable concentration only
at Well 15
3.6 x 102 3 Quantifiable concentration only
at Well 17
3.0 x I02 2
2.5 x 102 3 —
2.4 x 102 2 —
2.2 x I02 3 —
2.0 x Id2 3 —
1.2 x I02 3 —
1.3 x 103 3 High concentration only at Well 2
(J) No criterion available; criteria listed Is for » related compound. Trans-1-2 dlchloroethene Is
and much less toxic than 1-1-DCE.
(k) No criteria available, criterion listed Is for a related compound. A conservative criterion Is
reported to be noncarcl nogenl c
probably 10 times that shovn.
-------
The following 10 organic contaminants, which are not on the
priority pollutant list, were measured in the groundwater:
acetone
2-butanone
4 methyl phenol
o-xylene
benzoic acid
2-hexanone
styrene
benzyl alcohol
2 methyl phenol
2,4,5 trichlotophenol
Because there are no established water quality criteria for these com-
pounds, a detailed analysis was not conducted for them. Because these
compounds are closely associated, both chemically and physically, with
priority pollutant compounds measured at the site, the cleanup of
priority pollutants is expected to affect these non-priority pollutants
in a similar manner.
POST EXCAVATION CONTAMINANT CONCENTRATIONS
Surficial soils/fill will be removed from the entire site to a
depth equal to elevation 22 above mean sea level; subsurface fill
materials will be excavated from locations identified by the analysis of
historical site development and use. Figure A-3 indicates by location
the approximate depth of excavation.
The maximum concentrations of contaminants in subsurface soil on
the Western Processing site, both before and after excavation, are shown
in Table A-6. The maximum surface soil concentrations are also shown
for comparison. Soil removal will substantially reduce the maximum con-
centrations of inorganic contaminants in subsurface soil; for example,
cadmium will be reduced by 76 percent, nickel by 83 percent, and zinc by
92 percent. The organic contaminants, which often were detected and
quantified in only a few of the soil samples, reflect a contrasting pat-
tern. Many of the maximum organic concentrations were found at signifi-
cant depths, that is, below the levels to be excavated. In these cases,
the maximum concentrations will not be reduced at all. For those organ-
ics found only at a few locations higher in the soil depth profile, all
quantified concentrations will be removed and the resulting maximum
post-excavation concentration will be 0 (detection limit), or 100 per-
cent reduction. Thus, the resulting post-excavation pattern for organ-
ics is strongly bimodal, yielding either nearly 0 or nearly 100 percent
reduction in maximum concentration.
A-35
-------
-South 196th Street
.•/if:
Proposed
Site Excavation Plan
Note:
Elevations shown are in feet
above Mean Sea Level and
rep-resent the approximate
bottom of excavation
in that area of the site.
22
./ :^Hrea previously
/| excavated,
' I backfilled,
' I and paved
o>
-------
TABLE A-6
COMPARISON OF PRE- AND POST-EXCAVATION SOIL CONTAMINANT CONCENTRATIONS
BASED ON MAXIMUM CONCENTRATION
Contaminant
Al
Cr
Ba
Co
Cu
Fe
Ni
Mn
Zn
B
V
Ao
As
Sb
Se
Tl
Hg
Sn
Cd
Pb
CN
Surface
Samples
(in ppm) ^a'
4,700
5,300
150
16
890
18,900
740
2,900
81 ,000
170
140
6.1
38
98
1
0
0. 14
19
420
31,000
15
Subsurface
Samples
Pre- Post-
excavation excavation
19,500
7,600
180
12.4
5,700
13,400
1,900
2,800
40,500
240
76
1.4
102
130
30.5
1.5
0.36
10
402
141,000
179
6,200
1,300
84
0
1,240
10,500
320
1,400
3,100
170
0
1.4
6.8
3.4
0
1.5
0.36
3.2
98
5,200
22
Percent
Reduction
68.21
82.89
53.33
100.00
78.25
21.64
83.16
50.00
92.35
29.17
100.00
0.00
93.33
97.38
100.00
0.00
0.00
68.00
75.62
96.31
87.71
(a) The following contaminants, with maximum concentrations indicated, were found
only in surface soils:
17,000 ppb
2,600 ppb
29,000 ppb
200,000 ppb
130,000 ppb
The excavation plan would include removal of surface soil (1 foot)
over the entire site.
(b) Data shown are for 103 onsite subsurface soil sampling locations (excluding
offsite Wells 13 and 19).
(c) Values in ppm.
pentachlorophenol
di-N-butyl phthalate
di-N-octyl phthalate
benzo-B-fluoranthene
benzo-K-fluoroanthene
A-37
-------
TABLE A-6, Continued
Contaminant
2, 4-Dichlorophenol
2, 4-Dimethylphenol
Phenol
Aldrin
Dieldrin
4, 4 -DDT
4,4-DDD
Heptachlor
Lindane
PCB-1242
PCB-1254
PCB-1248
PCB-1 260
PCB-101 6
Acenaphthene
He xachloroe thane
1 , 2-Dichlorobenzene
Fluoranthene
Naphthalene
Bis (2-ethyl hexyl)
phthalate
Benzylbutylphthalate
Benzo(a ) -anthracene
Chrysene
Anthracene
Fluorene
Phenanthrene
Pyrene
Surface
Samples
(in ppm)*a)
0
1 1 , 000
19,000
0
145
0
0
0
34
137
3,300
2,046
2,030
0
5,090,000
0
2,200
234,000
6, 200,000
860,000
884,000
1,210,000
0
8,600,000
20,000,000
16,000,000
Pre-
excavation
7.900
10,000
65,000
2,860
3,340
129
100
2,960
11.8
1,780
407
19,600
1,710
3,160
8,700
1,800
565,000
7,700
13,000
410,000
9,100
4,000
2,500
1,600
16,900
62,400
11,000
Subsurface Samples (b'
Post-
excavation
7,900
10,000
65,000
0
0
129
0
0
0
810
0
1,510
111
0
8,700
1,800
0
7,300
13,000
31,000
9,100
0
0
0
16,900
62,400
11,000
d)
Percent
Reduction
0.00
0.00
0.00
100.00
100.00
0.00
100.00
100.00
100.00
54.49
100.00
92.30
93.51
100.00
0.00
0.00
100.00
5.19
0.00
92.44
0.00
100.00
100.00
100.00
0.00
0.00
0.00
(d) Values in ppb.
A-38
-------
TABLE A-6, Continued
Contaminant
Surface
Samples
(in ppm) (a^
Subsurface Samples (b»
Pre- Post-
excavation excavation
d)
Percent
Reduction
Benzene 0 199.5 199.5
1,1,1-Trichloroethane 0 174,000 16,000
1,1-Dichloroethane 0 17.3 17.3
Chloroform 0 18,000 18,000
Trans-1,2-Dichloroethene 0 34 34
Ethylbenzene 13 37,000 37,000
Methylene chloride 130 49,000 49,000
Fluorotrichloromethane 25 73 59
Tetrachloroethene 99 72,000 1,300
Toluene 0 394,000 394,000
Trichloroethene 37 580,000 558,000
0.00
90.80
0.00
0.00
0.00
0.00
0.00
19.18
98.19
0.00
3.79
A-39
-------
The effectiveness of the excavation plan in reducing contaminant
concentrations was also evaluated using average onsite soil concentra-
tions. The pre- and post-excavation comparisons of average soil con-
taminant concentrations are shown in Table A-7 (geometric averages) and
Table A-8 (site history averages). The pattern of results in these two
tables is very similar; the two approaches to calculating average con-
centrations yield consistent estimates of the percent reduction in
onsite soil contamination. Average inorganic contaminant concentrations
will be substantially reduced. The percent reduction for cadmium will
be 79 or 88 percent, for nickel 75 or 84 percent, and for zinc 78 or 84
percent; the analysis based on site history generally shows marginally
smaller reductions in average contaminant concentrations. The results
for organic contaminants are similar to those based on maximum con-
centrations. In most cases, the reduction in the average soil con-
centration of an organic contaminant will be either minimal or nearly
total; that is, the percent reduction achieved by excavation will be
near 0 percent or near 100 percent. This is a consequence of the
distribution of organic contaminants in onsite soils, a distribution
markedly different than for inorganic contaminants.
FLUSHING PROGRAM EFFECTIVENESS
The concept of reverse flushing that is incorporated in the PRP
groundwater extraction component, and the analytical and computer
modeling methods used to evaluate the effectiveness of this component,
are discussed in this section. The relative value of flushing to the
PRP plan is dependent on the implementation of other components of the
plan, particularly the excavation and diversion barrier components.
Flushing Concepts
The PRP groundwater extraction component includes a "reverse
flushing" concept for removing contaminants from groundwater and sub-
surface soil, including contaminants remaining after completion of the
soil excavation program.
The design of the flushing procedure to be used at the site has
assumed that a 40-foot deep diversion barrier (referred to hereinafter
as a "cutoff wall") will be installed around the entire site. This
A-40
-------
TABLE A-7
.COMPARISON OF PRE- AND POST-EXCAVATION SOIL CONTAMINANT CONCENTRATIONS
BASED ON GEOMETRIC AVERAGE CONCENTRATIONS
Contaminant
Al
Cr
Ba
Co
Cu
Fe
Ni
Mn
Zn
B
V
Ao
As
Sb
Se
Tl
Hg
Sn
Cd
Pb
CN
Pre-
excavation^3^
3,263
594.26
36.37
0.57
332.93
4,373
94. 1 1
368.32
2,578
60.68
2.40
0.01
3.28
8.59
0.83
0.01
0.01
0.81
34.72
5,451
11.16
Post-
exca vation ^a » ^ )
1,602
88.13
12.42
0
46.03
2,126
15.38
67.58
420.20
31.52
0
0.01
0.79
0.03
0
0.01
0.01
0.03
4.02
107.25
1.59
Percent
Reduction
50.90
85.17
65.86
100.00
86.17
51.38
83.66
81.65
83.70
48.06
100.00
0.00
75.91
99.65
100.00
0.00
0.00
96.30
88.42
98.03
85.75
(a) Values in ppm.
(b) The calculation of post-excavation average concentrations assumed clean back-
fill soils had zero concentrations of all contaminants.
A-41
-------
TABLE A-7 (Continued)
Contaminant
2, 4-Dichlorophenol
2, 4-Dimethylphenol
Phenol
Aldrin
Dieldrin
4,4-DDT
4,4-DDD
Heptachlor
Lindane
PCB-1242
PCB-1254
PCB-1248
PCB-1260
PCB-1016
Acenaphthene
He xachloroe thane
1 , 2-Dichlorobenzene
Fluor anthene
Naphthalene
Bis (2-ethyl hexyl) phthalate
Benzylbutylphthalate
Benzo(a) anthracene
Chrysene
Anthracene
Fluorene
Phenanthrene
Pyrene
Benzene
1,1,1 -Trichloroethane
1 , 1 -Dichloroe thane
Chloroform
Trans-1, 2-Dichloroethene
Ethylbenzene
Methylene chloride
Fluorotrichlorome thane
Tetrachloroethene
Toluene
Trichloroethene
Pre-
exca vation ( c '
208.60
218.15
1,652
6.08
7.10
2.92
0.77
6.23
0.09
79.03
4.33
341.27
38.13
50.32
75.86
19.15
13,007
155.75
226.52
12,238
79.35
47.84
29.90
19.14
147.37
719.80
184.42
1.53
2,870
0.13
143.25
0.99
523.87
1,486
3.21
1,196
6,437
19,267
Post-
excavation'"'c '
91.39
218.15
1,641
0
0
2.63
0
0
0
20.49
0
14.83
2.26
0
75.86
19.15
0
63.66
226.52
1, 386
79.35
0
0
0
147.37
636.08
95.92
1.53
126.34
0.13
143.25
0.71
521.98
670.96
1.79
51.62
5,378
7,282
Percent
Reduction
56.19
0.00
0.67
100.00
100.00
9.93
100.00
100.00
100.00
74.07
100.00
95.65
94.07
100.00
0.00
0.00
100.00
59.13
0.00
88.67
0.00
100.00
100.00
100.00
0.00
1 1.63
47.99
0.00
95.60
0.00
0.00
28.28
0.36
54.85
44.24
95.68
16.45
62.20
(c) Values in ppb.
A-42
-------
TABLE A-8
COMPARISON OF PRE- AND POST-EXCAVATION SOIL CONTAMINANT CONCENTRATIONS
BASED ON SITE HISTORY AVERAGE CONCENTRATIONS
Pre- Post- Percent
Contaminant excavation^3' excavation'3'*3' Reduction
Al
Cr
Ba
Co
Cu
Fe
Ni
Mn
Zn
B
V
Ag
As
Sb
Se
Tl
Hg
Sn
Cd
Pb
CN
3,353
438.90
34.49
0.44
294.25
4,198
63.94
255.18
2,043
69.88
1.99
0.01
1.98
3.02
0.31
0.01
0.01
0.38
20.21
2,729
6.37
1,947
98.38
16.81
0
59.05
2,572
15.88
72.62
440. 13
41.67
0
0.01
0. 76
0.02
0
0.01
0.01
0.03
4.23
82.57
2.31
41.93
77.58
51.26
100.00
79.93
38.73
75.16
71.54
78.46
40.37
100.00
0.00
61 .62
99.34
100.00
0.00
0.00
92. 1 1
79.07
96.97
63.74
(a) Values in ppm.
(b) The calculation of post-excavation average concentrations assumed clean back-
fill soils had zero concentrations of all contaminants.
A-43
-------
TABLE A-8 (Continued)
Contaminant
2, 4-Dichlorophenol
2, 4-Dimethylphenol
Phenol
Aldrin
Dieldrin
4,4-DDT
4,4-DDD
Heptachlor
Lindane
PCB-1242
PCB-1254
PCB-1248
PCB-1260
PCB-1016
Acenaphthene
He xachloroe thane
1 , 2-Dichlorobenzene
Fluor an thene
Naphthalene
Bis (2-ethyl hexyl) phthalate
Benzylbutylphthalate
Benzo(a) anthracene
Chrysene
Anthracene
Fluorene
Phenanthrene
Pyrene
Benzene
1,1,1 -Trichloroe thane
1 , 1 -Dichloroe thane
Chloroform
Trans-1, 2-Dichloroethene
Ethylbenzene
Methylene chloride
Fluorotrichlorome thane
Tetrachloroe thene
Toluene
Tri chloroethene
Pre-
excavation^c)
164.39
168.67
1,210
9.58
11.19
4.12
0.84
9.82
0.10
50.51
1.89
292.32
33.25
42.31
116.75
8.35
10,780
165.88
196.88
4,635
122.12
35.28
22.05
14.11
226.80
954.30
212.89
1.67
2,411
0.14
155.81
0.51
570.13
1,435
1.90
976.28
6,817
17,853
Post-
excavation (b, c )
77.95
168.67
1,204
0
0
3.80
0
0
0
11.91
0
18.15
3.27
0
116.75
8.35
0
97.97
196.88
853.62
122. 12
0
0
0
226.80
892.56
147.62
1.67
137.84
0.14
155.81
0.30
569.40
672.31
0.82
30.17
5,862
7,921
Percent
Reduction
52.58
0.00
0.50
100.00
100.00
7.77
100.00
100.00
100.00
76.42
100.00
93.79
90.17
100.00
0.00
0.00
100.00
40.94
0.00
81.58
0.00
100.00
100.00
100.00
0.00
6.47
30.66
0.00
94.28
0.00
0.00
41.18
0.13
53.15
56.84
96.91
14.01
55.63
(c) Values in ppb.
A-44
-------
cutoff wall, which will not be keyed into a continuous, low-permeability
stratum, will inhibit the horizontal migration of residual contamination
in the onsite soil and groundwater. Therefore, contaminant migration
beneath will occur vertically in contrast to the normally dominant hori-
zontal routes. The cutoff wall will also isolate the remaining con-
taminated groundwater and soil from the surround-ing shallow groundwater
flow. Thus, installation of the cutoff wall would significantly reduce
the rate of migration of remaining contamination, even without flushing
(groundwater extraction).
The excavation program will have little effect on the existing
levels of contamination in groundwater beneath the site. Unless addi-
tional remedial measures are implemented, this contaminated groundwater
would eventually escape into the upper aquifer by moving vertically
downward under the bottom of the cutoff wall, and into the existing
groundwater flow. The vertical migration route requires more time than
the existing groundwater flow for contaminants to leave the site.
Thus, without flushing, contaminant migration with a cutoff wall in
place would result in the release of lower concentrations of con-
taminants but over a longer time period as compared to the present site
conditions.
During groundwater extraction, the contaminated groundwater
pumped from within the cutoff wall will be replaced by relatively uncon-
taminated groundwater from outside and below the cutoff wall. Because
the contamination in the groundwater and soil is in general
equilibrium, "flushing" the soil with less contaminated groundwater
pumped from outside the cutoff wall will establish a new equilibrium by
"leaching" contaminants from the soil. Thus, the net effect of the
pumping will be to flush the mobile contaminants from the soil with
groundwater and pump the contaminated groundwater to a treatment
facility to remove contaminants prior to approved discharge.
The groundwater extraction program will not remove all of the con-
tamination remaining after the surface cleanup and onsite soil excava-
tion for two main reasons. First, the mechanisms by which the
contamination in groundwater and soil establish equilibrium are pro-
bably only partially reversible for most contaminants. In addition,
A-45
-------
these mechanisms, which include adsorption and chemical reactions, are
probably hysteretic and/or non-linear. Thus, adsorption and desorption
are not simple "reversing" mechanisms. Second, the release and migra-
tion of contaminants are time dependent. The proposed groundwater
extraction program will not continue long enough to have a significant
effect on the concentrations of contaminants of low mobility.
A general evaluation of the effectiveness of the groundwater
extraction/flushing operation can be made by comparing the current rate
of infiltration with the rate of water withdrawal during pumping. About
6 inches of precipitation per year is estimated to infiltrate through
the site surface. This value is slightly higher than the regional
infiltration rate because of higher infiltration through the bare soil
of the site. This higher infiltration rate at the site is documented by
the groundwater mound beneath and in the vicinity of the site.
Assuming a rate of 6 inches per year and a site area of 13 acres,
the total average yearly infiltration is approximately 2 million
gallons. At the pumping rate of 1 million gallons per week included in
the PRP plan, the ratio of groundwater withdrawal rate to the current
rate of infiltration will be 52:2. Thus, the "reverse" flow rate during
each year of pumping will be equivalent to about 26 years of the normal
infiltration rate.
Groundwater Flow Model
A two-dimensional finite-element groundwater flow model was used
to assist in assessing the effectiveness of the proposed flushing
program. The model used, acronymed FPM, is part of the six-model Colder
Groundwater Package (Colder Associates, 1983). The FPM program is based
on mathematical equations by Bredehoeft and Pinder (1973) that are valid
for general three-dimensional, variable-density groundwater flow.
However, the FPM program is written for two-dimensional flow in a ver-
tical planar or axi-symmetric section. It is capable of performing both
steady state and transient analyses. The solutions to the basic
equations are approximated by a Galerkin optimization procedure.
A-46
-------
The limitations and assumptions on which the solution of the
general flow equations are based are as follows:
1. Darcy's Law is valid.
2. The solid skeleton of the aquifer deforms linearly and elasti-
cally.
3. The groundwater obeys a linear equation of state.
4. The aquifer properties are independent of pressure and salinity
changes.
5. Groundwater flow due to gradients of salinity, temperature, or
electric potential is negligible.
The finite-element mesh used for the analysis of the effectiveness
of flushing was developed using subsurface information from several
shallow borings drilled on and immediately adjacent to the Western
Processing site by the Environmental Protection Agency (EPA). The mesh
is shown on Figure A-4.
Use of the model is predicated on the identification and quantifi-
cation of several boundary conditions. The driving forces for ground-
water flow within the mesh are the regional groundwater gradient, esti-
mated to be parallel to the ground surface with a slope of approximately
1.25 feet per 1,000 feet, and the quantity of water pumped from within
the cutoff wall in the proposed flushing program. The quantity pumped,
1 million gallons per week, was assumed to be pumped or removed from the
mesh nodes indicated on Figure A-4.
Physical Properties
The aquifer properties requiring definition for use of the model
are hydraulic conductivity, storativity and/or specific yield, and poro-
sity. The hydraulic conductivity of the five different soil types and
the cutoff wall used in the flushing model were estimated using empiri-
cal relationships based on grain size interpreted from the written soil
descriptions in the EPA exploration logs. No laboratory or field
test data were available to corroborate these estimates at the time the
modeling was accomplished. Table A-9 summarizes the values of hydraulic
conductivity and the values for other key variables used in the model.
Artesian conditions were not modeled for the analysis of the flushing
A-4 7
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o 200 400
Horizontal Seal* In F««t
Finite Element Grid for the Flushing Model
Figure A-4
-------
TABLE A-9
FLUSHING MODEL PHYSICAL PARAMETERS
Parameter
Soil Unit (a>
A B C D E F
Effective porosity
Horizontal hydraulic
conductivity (cm/sec)
Vertical hydraulic
conductivity (cm/sec)
Longitudinal disper-
sivity (ft)
Transverse disper-
sivity (ft)
Density (grams/cc)
Percent organic carbon
0.25 0.27 0.35 0.35 0.30 0.35
3.5x10-3
1x10~7 3.5x10~4 5x10~3 2x10~3
3.5x10-4 1x1O-3 1x10~7 3.5x10~5 5x10~4 2x1O"4
40
50
1
8 10
1.60 1.51
1 1
30
40
1 6 8
1.58 1.31 1.44
3 2 1
10
2
1.27
3
(a) See Figure A-4 for soil unit designations.
program, so an estimate of the value or values of storativity for the
different soil types is not required. However, a value for specific
yield, sometimes referred to as drainable porosity, is required for the
evaluation of non-pressured groundwater. A specific yield value of
0.10 was used for each of the six soil types (including the cutoff
wall).
The porosities of the soil units modeled were estimated from an
evaluation of the degree of saturation, moisture content, and dry den-
sity of numerous soil samples obtained from reports describing borings
drilled in the vicinity of the Western Processing site. The borings
used were drilled for numerous other projects and purposes in the site
vicinity; they were not drilled during the EPA investigation. A summary
of this analysis is shown on Figure A-5. The effective porosities used
for the various soil types (listed in Table A-9) were assumed to be two-
thirds of the total porosities estimated as described above.
A-49
-------
The FPM program is capable of considering hydrologic factors such
as precipitation and evapotranspiration. The net effect of average
annual precipitation, runoff, and evapotranspiration was incorporated
into the model using a net inflow of 4.5 inches per year for infiltra-
tion outside of the cutoff wall. Inside the cutoff wall, recharge due
to the planned disposal of storm runoff from the site surface through an
onsite infiltration system was calculated to be 35 inches per year (90
percent of the annual average precipitation) and used as model input.
Contaminant Transport-Solute Model
The solute transport model used, acronymed SOLTR, is also a primary
component of the Colder Groundwater Package. It is capable of esti-
mating a steady state or transient solution of solute concentrations
based on chemical properties specific to the contaminant being analyzed
and on boundary conditions established by the results of hydraulic
modeling. A solution to the groundwater flow model is required as
input to the solute transport model. Since the model is capable of ana-
lyzing the distribution of only a single contaminant at one time, the
interaction between different contaminants was not modeled.
In SOLTR, contaminant movement is modeled as the combination of
advection (the bulk movement of the contaminant with flowing ground-
water) and hydrodynamic dispersion (the movement of the contaminant in
response to concentration gradients). The model is written so that dif-
fusion can be incorporated into the latter term, although diffusion is
generally not significant. For the analysis of contaminant movement
from the Western Processing site, diffusion was not considered. An
important feature of the solute transport model is that it is capable of
considering the effects of (1) physical retardation, or (2) chemical or
biological decay, also a form of retardation. The "loss" of con-
tamination by chemical or biological decay was not considered in the
analysis of the Western Processing situation; however, physical retar-
dation is a very important aspect in the estimation of contaminant move-
ment.
Retardation. Physical retardation is assumed to be a linear rela-
tionship and is defined as the ratio of the rate of movement of ground-
A-50
-------
120-1
110 -
100 -
O BO
U
g so
0
§
O
5 70
tu
O
>- eo
S
60 -
40 ~
Legend:
OL - Organic silt
SP - Poorly-graded sand
PT - Peat
ML - Silt
SM - Sllty sand
8W - Well-graded aand
I
I
I
0.20
0.30
0.40 0.60 0.60
POROSITY
-------
water to the rate of movement of the contaminant. Physical retardation
occurs primarily as a result of chemical reactions between the con-
taminant and the aquifer soil matrix, and adsorption-desorption activity
between the contaminant and the aquifer matrix. The general mathemati-
cal formulation of retardation is as follows:
Rd = 1 + -„ Kd
Where:
R<3 = retardation coefficient or factor
Kjj = partition coefficient
= soil mass density (grams/cc)
n = soil effective porosity
As indicated by this relationship/ the retardation of an individual con-
taminant in a particular type of soil is directly related to a value
referred to as the partition coefficient. This coefficient is a measure
of the affinity of the particular contaminant for a particular soil.
However, the determination of this coefficient is relatively difficult.
Partition Coefficients: Metals
Several factors are important when considering the partitioning of
metals in the soil-groundwater medium. The element's combination with
other ions, and thus its movement, is largely dependent upon the pH,
quantity of clay and organic matter, and the oxidation-reduction status
of the soil. In general, when the pH of the soil is greater than
approximately 6.5, most heavy metals are bound to the soil and are not
readily "available" to the groundwater. Availability also decreases
with increasing cation exchange capacity (CEC, the total exchangeable
cations that each soil unit can hold by adsorption) of the soil. CEC
increases as the organic and clay content of the soil increase.
Aluminum, iron, and manganese hydroxides also play an important role in
combining with trace metals and decreasing their mobility. In addition,
a well-aerated soil will generally decrease mobility of trace metals by
decreasing the metals' solubilities as a result of increasing the oxida-
tion state.
A- 52
-------
EPA measurements at Western Processing show that the pH of the
groundwater varies widely, from 4.6 to 13, indicating that the availa-
bility of the metals to the groundwater, and the form of the cations,
varies significantly from one area to another. The pH of the soil plays
a key role in the leachability of the metals. By decreasing the pH in
areas of alkaline groundwater, the metals concentrations in the ground-
water will significantly increase, although the amount of increase is
dependent upon the specific metal and the mechanisms by which it is
bound in the soil.
The CECs have not been established specifically for soil units on
the site. However, the CEC for a silt loam and a gravelly loam sand in
King County is reported to vary between 6.0 and 36.6 milliequivalents
(meq)/100 gm (U.S. Department of Agriculture, 1973). These values apply
to near-surface soil which is high in organic matter due to tillage; the
CEC for soil at depth is probably lower. By totaling the average
meq/100 gm for each cation reported in the EPA's analysis of soil
samples from the site (see Table A-10), a value of 34.5 meq/100 gm is
obtained. This is near the upper end of the expected range of CEC for
the soil (6.0 to 36.6 meq/100 gm), but does not include other signifi-
cant cations (calcium, sodium, potassium, and magnesium) that are pro-
bably present. Therefore, it is a conservative total of cations that
are available for adsorption to exchange sites. Because the total
cation pool exceeds the expected CEC of the soil, precipitation by
various anions (e.g., sulfate, phosphate, and nitrate), adsorption by
hydroxides, and/or chelation by organic compounds must also be important
mechanisms for binding metals contaminants at the Western Processing
site.
To assess the availability of the various cations, critical
limiting factors for availability must be evaluated for each cation
separately. To determine which cations are most important to evaluate,
several factors were used to assess relative potential environmental
impact. The most important of these are: (1) a ratio of the average
groundwater concentration of the element (weighted on the basis of site
history) and the lowest freshwater criterion for each of the priority
pollutant metals, and (2) a ratio of the average soil concentrations at
A-53
-------
the site after soil excavation and the recommended maximum residual soil
concentrations based on current literature (EPA 1983) and experience.
The results of the ranking are presented in Table A-11.
TABLE A-10
EXCHANGEABLE CATIONS
Average g/g
in Onsite Soil Cations
Metal After Fill Removal in meg/100 gm
Al 3+
Cr 3+
Cu 2+
Fe 2+ (a)
Ni 2+
Mn 2+ (a)
Zn 2+
B 3+
Pb 2+
1,947
98.
59.
2,572
15.
72.
440.
41.
82.
4
1
9
6
1
7
6
21.
0.
0.
9.
0.
0.
1.
1.
0.
65
57
18
21
05
26
35
16
08
Total 34.5
(a) Reduced valence state of Fe and Mn used (assumes
anaerobic conditions).
TABLE A-11
RELATIVE RANKING OF METALS
Rank
1
2
3
4
5
6
Metal
Cd
As
Zn
Ni
Pb
Cu
Method A
-------
With the exception of arsenic, both ranking systems used had the
same five elements in the five highest ranks, although the order of
these elements differed between the two systems. Arsenic concentrations
in the soil are generally low and arsenic ranks low relative to the
recommended maximum soil concentration (ratio = 0.003). Thus, although
arsenic was present in a few groundwater samples from the Western
Processing site at elevated levels, the levels in the soil indicate that
the long-term potential for arsenic contamination is not significant.
Zinc and lead are the only metals whose concentrations would be
greater than the suggested maximums for soil to be left at closure of a
waste site (EPA 1983). For these and the metals below the maximum
suggested concentrations, some form of immobilization is necessary to
minimize or prevent environmental contamination off site.
Lead concentrations will be the most difficult to decrease in the
soil. Lead strongly adsorbs to the soil when present as a cation and,
depending on the anions present, could remain in the soil as insoluble
sulfates, phosphates, or carbonates. Hydrous iron oxides and hydrous
aluminum oxides also will strongly bind lead (the selection sequence for
hydrous iron oxides has been found to be: Pb> Cu> Zn> Ni> Cd [Nriagu
1980]; aluminum hydrous oxide adsorbs metals in a slightly different
sequence: Cu> Pb> Zn> Ni> Cd, with lead being only slightly less closely
held than copper).
Lead is found in groundwater at the Western Processing site at
elevated levels as deep as 130 feet, indicating that it has probably
been in the soil for an appreciable length of time. The movement of
lead may also have been aided by burial of lead-laden material or by the
occurrence of acidic conditions.
Cadmium and nickel are bound much less strongly than lead by soil
adsorption and hydrous oxides. The quantities of cadmium and nickel
remaining after flushing are expected to be associated mostly with pre-
cipitated metals (e.g., cadmium carbonate, cadmium phosphate, and/or
cadmium sulfide) rather than that adsorbed to the soil. The low con-
centrations of cadmium and nickel in the deep wells (130 feet) indicate
that the cadmium and nickel have not migrated far through the ground-
water.
A-55
-------
For those remaining trace metals of concern (copper and zinc), the
extent of removal by flushing will vary based on the same considerations
of chemical precipitation as lead, cadmium, and nickel, with the
strength of adsorption to the soil intermediate between the relatively
strong adsorption of lead and the relatively weak adsorption of cadmium
and nickel.
Aluminum occurs at elevated levels throughout the groundwater at
the site. Because the aluminum values reported for the soils were not
determined using a total acid digestion of the soil, the total amount of
aluminum in the soils cannot be assessed. Based on the groundwater
data, aluminum is present at depths as great as 130 feet, indicating
that leaching of aluminum has been occurring for many years. At a pH of
from 4 to 10, aluminum is not readily available to the groundwater, but
is instead bound in the form of hydrous oxides. These hydrous oxides
will adsorb metals from the groundwater, thus greatly increasing the
potential for metal fixing. As aluminum is flushed from the groundwater
system, additional metals could be released as the aluminum
hydroxides solubilize. However, since the hydrous oxides are soluble
only at the extreme ends of the pH range, aluminum should be strongly
bound in the neutral pH range expected during flushing. An exception
would be if large amounts of fluoride are present. Because fluoride was
not analyzed by the EPA, it is not known whether enough fluoride is pre-
sent to affect the aluminum solubility.
Overall, if the pH of the soil and groundwater at the site
equilabrates to a pH of 6.5 or greater, the trace metals of most concern
(Cu, Ni, Pb, Cd, and Zn) that remain after flushing will form hydroxides
and will not be available to the groundwater. Large quantities of
sulfates, carbonates, or phosphates could keep the metals fixed in the
soil.
The above discussion provides a background on the mechanisms that
control the partitioning of metals between groundwater and soil. To
estimate the retardation of individual metals migrating in groundwater,
it is necessary to quantify these mechanisms.
No method could be found in the literature to adequately address
the inherent variation in partition coefficient for a specific metal in
A-56
-------
relation to soil type, environmental conditions (particularly pH), and
the presence of other contaminants. For this reason, the partition
coefficients for metals were estimated using available data for onsite
measurements of contamination in both the soil and groundwater. A
significant effort was expended in attempting to identify the form and
variation in the partition coefficients over the wide range of physical
and environmental conditions and concentrations existing at the site.
Multivariate regression analyses were attempted using various environ-
mental parameters as covariants. With few exceptions, these efforts did
not provide usable relationships. As a result, the partition coef-
ficients for metals were established on the basis of the ratio of the
average concentration of a contaminant in the soil to that in the
shallow groundwater. As indicated in Table A-12, the partition coef-
ficients for metals are all larger than 1. For comparison, Table A-12
also lists partition coefficients for organics determined in the same
manner, although these were not used in the analyses. In the case of
lead, the coefficient is over 7,000. Partition coefficients of 10 or
more generally indicate a contaminant with very low mobility in an
aqueous environment.
Partition Coefficients: Organics
Organic compounds may have many different fates in the soil and
groundwater environment: (1) they may be adsorbed to the soil, (2)
they may be leached through the groundwater, (3) they may volatilize
and be lost to the atmosphere, (4) they may be broken down by organisms,
and (5) they may undergo chemical reactions with other materials.
Volatilization of the compounds to the atmosphere would be ex-
tremely limited at the site because most of the volatile contamination
is present well below the ground surface. The breakdown of chemicals by
organisms would also be severely limited without flushing, since there
would be toxic quantities of trace metals and solvents remaining in the
soil. For example, microbial metabolism of organic chemicals can be
inhibited by values of 0.5 mg/1 of copper or 5.0 mg/1 of zinc in the
groundwater (Matthess 1982). Without flushing, the concentrations of
these metals would be expected to be much greater than these values.
A-57
-------
TABLE A-12
PARTITION COEFFICIENTS BASED ON CONCENTRATION RATIOS
Average Concentrations (ppm)^a^
Contaminant Shallow Wells
Cadmium
Zinc
Nickel
Chromium
Arsenic
Lead
Copper
Mercury
Aluminum
Methylene chloride
Chloroform
Trichloroethene
Trans -1 , 2-dichloroethene
Benzene
Phenol
1,1,1 -Trich lor oe thane
Toluene
2.1
139.7
15.5
4.25
0.014
0.36
1.47
0.00036
71.6
46.7
2.14
27.9
18.0
0.20
72.4
18.9
2.32
Soil Samples
20.2
2,043
63.9
439
1.98
2,729
294
0.010
3,350
1.4
0.16
17.9
0.0005
0.0017
1.2
2.4
6.8
Partition
Coefficient(b>
10
15
4
103
141
7,456
201
28
47
0.030
0.075
0.64
0
0.008
0.02
0.13
2.9
(a) Weighted on basis of site history.
(b) Partition coefficient calculated as follows:
concentration in soil
concentration in shallow wells
The organic chemicals will probably undergo various chemical reac-
tions during the period of time they remain in the soil, with the speci-
fic reactions dependent primarily upon the pH and the presence of other
chemical species. Chemical degradation has been shown to occur slowly
in sterile anaerobic soils for phenol and its chlorinated derivatives
such as 2,4,6-trichlorophenol and pentachlorophenol (EPA 1983).
However, the reactions and degradations that might occur at the site are
not possible to predict since such a wide range of chemical environments
is present.
The tendency for an organic compound to partition between water and
soil solids can be estimated using solubility relationships. The more
soluble a chemical, the greater tendency it will have to be in the water
phase. However, partitioning is also directly related to the organic
carbon content in the soil; the higher the organic carbon content, the
more an organic compound will be bound by the soil solids.
A-58
-------
To estimate the degree that an organic compound is adsorbed to
soil, the partition coefficient, Kd, can be determined by the following
relationship (Conway 1982):
Koc
Kd = x (% Organic Carbon)
100
where:
Kd = partition coefficient (amount adsorbed by the soil [oven-dry
basis] divided by the amount of the chemical in the water
[units of grams/cubic centimeter])
KOC = soil adsorption coefficient
KOC constants for various organic chemicals can be obtained
indirectly by estimation from known values for water solubility (S).
The octanol-water ratio (KQW) can also be used, but since KOW is a more
difficult value to determine and since a direct relationship between Koc
and solubility (S) in water has been demonstrated (Chiou 1977), solubi-
lity values were used to assess KOC. The following regression equation
was used to estimate KQC (Conway 1982):
log KQC = 3.64 - 0.55 (log S)
where:
S = solubility in water (ppm at 25° C)
Using this relationship to obtain KQC, Kd was calculated for the
Priority Level 1 and 2 organic. A listing of the partition coefficients
using percent carbon as a variable is shown in Table A-13. The com-
pounds most readily available to the groundwater are those with the
lowest partition coefficients.
Retardation Coefficients
Using the physical properties of the soil units listed in Table
A-9, the partition coefficients for metals listed in Table A-12, and the
partition coefficients for organics listed in Table A-13, the retar-
dation coefficients for use in the flushing model were estimated using
the previously described relationship. These are summarized in Table
A-14.
A-59
-------
TABLE A-13
PARTITION COEFFICIENTS FOR ORGANICS (SOLUBILITY METHOD)
Organic Chemical
Phenol
Methylene chloride
1 , 2-dichloroe thane
Chloroform
1 / 1 -Dichloroe thane
1,1,1 -Trich lor oe thane
Benzene
Tri chloroethene
2, 4, 6-Trichlorophenol
Trans-1 , 2-dichloroe thene
Toluene
Pentachlorophenol
Partition Coefficient'3)
1%C
0.08
0.21
0.30
0.31
0.38
0.43
0.85
0.93
1.10
1.29
1.38
10.2
2%C
0.16
0.42
0.60
0.62
0.76
0.86
1.70
1.86
2.20
2.58
2.76
20.4
3%C
0.24
0.63
0.90
0.93
1.14
1.29
2.55
2.79
3.30
3.87
4.14
30.6
AUC i^ai *~L U.LVJ11 WWCi J-X^-LCIIU XO XJCl&CU *JI1 aU-LUJ.
of percent organic carbon in the soil (%C).
TABLE A-14
RETARDATION COEFFICIENTS FOR THE FLUSHING MODEL
Retardation Coefficient by Soil Unit'a>
Contaminant
Cadmium^
Zinc(b)
Nickel
-------
The retardation coefficients for organic compounds were also deter-
mined using partition coefficients estimated from the water and soil
concentrations reported by EPA for organic compounds found at the site.
Retardation coefficients determined by both methods (for organics) and
by site data (for metals) are summarized in Table A-15 for comparison
purposes. Overall, those based on the soil and water data from the site
are lower than the values based on solubility relationships for organic
contaminants. The lower values could be due to (1) the loss of the
volatile compounds from the soil during sampling and handling, and/or
(2) lower laboratory recovery rates from the soil matrix analyses in
comparison to rates associated with water sample analyses. (These types
of losses do not occur as easily when sampling and analyzing for trace
metals. )
TABLE A-15
TYPICAL
Substance
Cadmium
Zinc
Nickel
Chromium
Arsenic
Lead
Copper
Mercury
Aluminum
Methylene chloride
Chloroform
Tri ch lor oe thene
Trans-1 , 2-dichloroe thene
Benzene
Phenol
1,1,1 -Trichloroethane
Toluene
RETARDATION COEFFICIENTS
Retardation
From Onsite
Measurements
49
73
20
500
678
36,000
1,000
135
225
1.2
1.4
4.1
1.0
1.0
1.1
1.6
15.0
Coefficient*3'
Based on
Solubility
._
—
—
—
—
—
—
2.0
2.5
5.5
7.2
5.1
1.4
3.1
7.6
(a) Retardation coefficients vary with soil type. Typical values listed
in this table are for a silty sand assuming an effective porosity
(n) = 0.30, a bulk dry density ( ) = 1.44 grams per cubic cen-
timeter, and (for organics based on solubility) an organic carbon
content in the soil of 1 percent.
Dispersion. Hydrodynamic dispersion is a combination of diffusion and
the physical spreading of a contaminant by mixing within the pore spaces
A-S1
-------
of the aquifer matrix. Diffusion is strictly a function of the dif-
ference in concentration between two points, whereas the physical mixing
occurs in response to the velocity of groundwater flow as well as con-
centration gradients. Dispersion is strongest in the direction of
groundwater flow, but also occurs in the direction normal
(perpendicular) to groundwater flow. This so called transverse disper-
sion is less than that in the primary direction of flow, referred to as
longitudinal dispersion.
Dispersion is described by dispersion coefficients, which are
required input parameters to the SOLTR model. Neglecting diffusion, the
value of the coefficients of longitudinal and transverse dispersion are
equal to the groundwater flow velocity multiplied by the longitudinal
and transverse dispersivity, the units of which are length. Disper-
sivity values are dependent on the type of aquifer material and are dif-
ficult to estimate. For the analysis of contaminant movement from the
Western Processing site, the values for dispersivity and therefore the
dispersion coefficient were estimated on the basis of published infor-
mation for an investigation of contaminant migration in soil similar to
that at the site (Perlmutter and Lieber 1970). The values used in the
flushing model are listed in Table A-9. Although it is believed that
the values used are reasonable, substantiation of their accuracy would
require additional data, analyses, and possibly field testing.
Initial Contaminant Concentrations. The initial concentrations of con-
taminants used in the analysis of the effectiveness of the proposed
flushing operation were established using the chemical data developed by
the EPA during the initial site investigation. Estimates of con-
tamination levels were for depth intervals below the site ground surface
inside the site fence line, as previously described. For the purpose of
the analysis of flushing effectiveness, the average concentration at the
10-foot depth was assumed to apply to the depth zone from the water
table to a depth of 25 feet, and the average concentrations for the 30-,
50-, and 130-foot depths were assumed to apply between 25 and 45 feet,
45 and 80 feet, and below 80 feet, respectively.
A-62
-------
Results
The higher partition coefficients of the metal contaminants indica-
te that they would not be likely to move rapidly from the Western
Processing site to distant receptors. Conversely, the generally low
retardation characteristic of the various organic contaminants suggests
that relatively rapid movement of these contaminants in groundwater can
be expected. Although the lower retardation factors suggest that the
organic contaminants, particularily the volatile organics, will move in
groundwater more rapidly than the metals, they also indicate that the
flushing operation will be more rapid and effective for organics than
for metals.
The flushing model indicates that most of the residual Priority
Level 1 and 2 organic contaminants remaining after excavation are
reduced by at least 85 percent assuring 5 years of flushing, whereas the
reduction of remaining metal contaminants is generally below 50 percent
of post-excavation levels.
Table A-16 provides a summary of the contamination concentration
averages, partition/retardation coefficients, water quality criteria,
and diminution factors previously discussed. It also provides the
calculated pre- and post-excavation mass for each Priority Level 1 and 2
contaminant, and the post-flushing (post groundwater extraction) con-
taminant mass that would be achieved by the PRP plan.
Line 11 on Table A-16 lists the total mass in pounds for each con-
taminant in the groundwater. This total mass was obtained by summing
the weights of the contaminant in each depth zone to 200 feet. The
depth zones used were: 10 to 25 feet, 25 to 45 feet, 45 to 80 feet, and
80 to 200 feet. The concentrations used for each depth zone are listed
in Lines 1, 3, 4, and 5, respectively. The total contaminant mass for
each zone was obtained by using the following equation:
A-63
-------
TABLE A-16
CONTAMINANT CONCENTRATIONS AND EFFECT OF PRP
EXCAVATION AND GROUNDWATER EXTRACTION PROGRAMS
Parameter No. and Description
1
2
3
4
5
6
7
8
9
to
II
12
13
14
15
16
17
18
19
AYG. CONTAM. CONCENTRATION* b>
SH, Shallow GW (ppb)
SH. Soil (ppb)
Geom., 30- ft GW (ppb)
Geom., 50- ft GW (ppb)
Geom., 130- ft GW (ppb)
PARTITION/RETARDATION
Ratio Cone. Sol I/GW
Partition Coefficient (Kd)
Retardation Factor (Rp)
QUALITY/DIMINUTION
Water Quality Criteria (ppb)
Diminution Factor
PRE-EXCAVATION MASS
Mass In GW (Ibs)
Mass In Soil (Ibs)
Total Mass (Ibs)
POST-EXCAVATION MASS
Mass In GW (Ibs)
Mass In Soil (Ibs)
Total Mass (Ibs)
POST-FLUSHING MASS
Mass In GW (Ibs)
Mass In Soil (Ibs)
Total Mass (Ibs)
Cd
2,100
20,210
1,011
0.41
6.28
9.6
10
49
0.012
175,000.00
483
11,660
12,143
483
2,440
2,923
362
1,830
2,192
Al
71,564
3,353,000
101,662
29,530
19,579
46.9
47
225
1
72,000
59,700
1,930,000
1,989,700
59,700
1,120,000
1,180,700
57,320
1,075,000
1,132,320
Cr+6<»>
4,251
438,900
366
29
27
103.2
103
494
0.29
15,000
688
253,000
253,688
688
56,700
57,388
688
56,700
57,388
As
14
1,980 2
13
20
57
139.7
140
678
0.0022
6,400
73
1,140 1
1,213 1
73
438
511
73
438
511
Zn
139,732
,043,000
124,928
190
279
14.6
15
73
47
3,000
42,640
,180,000
,222,640
42,640
254,170
296,810
34,111
203,000
237,111
Nl
15,471
63,940
14,795
10
64
4.1
4
20
13.4
1,200
4,930
36,900
41,830
4,930
9,170
14,100
2,610
4,860
7,470
Pb
366
2,729,000
275
76
57
7,456.3
7,456
36,000
0.75
490
189
1,570,000
1,570,189
189
47,570
47,759
189
47,570
47,759
Cu
1,467
294,250
787
101
79
200.6
201
966
5.6
260
469
170,000
170,469
469
34,100
34,569
469
34,100
34,569
Cr*3<8)
4,251
438,900
336
29
27
103.2
103
495
44
97
688
253,000
253,688
688
56,700
57.388
688
56,700
57,388
Ag
1.54
10
0.00
0.00
0.00
6.5
6.5
31
0.12
13
2.12
5.77
7.89
2.12
5.77
7.89
1.27
3.46
4.73
He
0.04
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.007
5.9
0.005
0.00
0.005
0.005
0.00
0.005
0.00
0.00
0.00
Hg
0.36
10
13
0.13
0.00
27.8
28
135
0.14
2.54
2.50
5.77
8.27
2.50
5.77
8.27
2.4
5.48
7.88
(a) The data reported by EPA on Cr concentrations are represented In both Cr+6 and Cr+3 columns. EPA (1983) stated that samples
containing chromium were checked for hexavalent chrome, but none was found. Therefore the CR*3 Is probably more appropriate
for evaluating the Western Processing site.
(b) SH » site history based; geom. • geometric-based.
-------
TABLE A-16 (continued)
Parameter No. and Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
AVG. CONTAM. CONCENTRATION*6'
SH, Shallow GW (ppb)
SH, Sol 1 (ppb)
Geom., 30- ft GW (ppb)
Geom., 50- ft GW (ppb)
Geom., 130- ft GW (ppb)
PARTITION/RETARDATION
Ratio Cone. Sol I/GW
Partition Coefficient (Kd)
Retardation Factor (Rp)
QUALITY/DIMINUTION
Water Quality Criteria (ppb)
Diminution Factor
PRE -EXCAVATION MASS
Mass In GW (Ibs)
Mass In Sot 1 (Ibs)
Total Mass (Ibs)
POST-EXCAVATION MASS
Mass In GW (Ibs)
Mass In Sol 1 (Ibs)
Total Mass (Ibs)
POST-FLUSHING MASS
Mass In GW (Ibs)
Mass In Soil (Ibs)
Total Mass (Ibs)
Trans- 1,2-
Dlchloro- Methyl ene Chloro-
ethene Chloride form
17,963
0.51
157
0.00
21
0.000028
1.29
7.2
0.033
544,000
2,530
0.29
2,530
2,530
0.17
2,530.17
304
0.02
304.02
46,682
1,435
50,660
0.00
19
0.030
0.21
2.0
0.19
246,000
15,780
828
16,608
15,780
388
16,168
1,420
35
1,455
2,135
156
2,193
0.00
0.00
0.075
0.31
2.5
0.19
11,000
697
90
787
697
90
787
35
4.5
39.5
Trlchloro- 1
ethene
27,859
17,853
7,740
49
0.00
0.64
0.93
5.5
2.7
10,000
5,280
10,300
15,580
5,280
4,530
9,812
845
725
1,510
1,2-01-
1, 1-Dlchloro- chloro-
ethane Dleldrln Aldrln ethane
1,484
0.14
0.00
0.00
0.00
0.00009
0.38
2.8 1,
0.94
1,600
205
0.08
205.08
205
0.00
205
12
0.005
12.005
0.06
11.19
0.00
0.00
0.00
186.5
350
700
0.000071
845
0.008
6.50
6.508
0.008
0.00
0.008
0.008
0.00
0.008
0.06
9.58
0.00
0.00
0.00
160.0
330
1,600
0.000074
811
0.008
5.50
5.508
0.008
0.00
0.008
0.008
0.00
0.008
627
0.00
0.00
0.00
0.00
0.00
0.30
2.4
0.94
667
86
0.00
86
86
0.00
86
4.30
0.00
4.30
Fluro-
trlchloro-
methane Benzene
72.96
1.90
0.00
0.00
0.00
0.026
0.93
5.5
0.19
384
10
1.1
11.1
10
0.47
0.47
0.00
0.00
0.00
199
1.67
0.00
0.00
0.00
0.008
0.85
5.1
0.66
302
28
0.96
28.96
28
0.96
28.96
2.80
0.096
2.896
I.I-OI-
chloro-
ethene Phenol
8.471
0.00
0.00
0.00
0.00
0.00
1.60
8.7
0.033
257
1.20
0.00
1.20
1.20
0.00
1.20
0.22
0.00
0.22
72,350
1,210
1,547.6
0.0
0.0
0.0
0.0
1.3
300
241
10,270
698
10,968
10,270
695
10,965
308
21
329
-------
TA9LE A-16 (continued)
Parameter No. and Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
AVG. CONTAM. CONCENTRATION*1"'
SH, Shallow GM (ppb)
SH, Soil (ppb)
Geom., 30-ft GW (ppb)
Geom., 50-ft GW (ppb)
Geom., 130-ft GW (ppb)
PARTITION/RETARDATION
Ratio Cone. Sol 1 /GW
Partition Coefficient (Kd)
Retardation Factor (Rp)
QUALITY/DIMINUTION
Water Quality Criteria (ppb)
Diminution Factor
PRE-EXCAVATION MASS
Mass In GW (Ibs)
Mass In Sol 1 (Ibs)
Total Mass (Ibs)
POST-EXCAVATION MASS
Mass In GW (Ibs)
Mass In Sol 1 (Ibs)
Total Mass (Ibs)
POST-FLUSHING MASS
Mass In GW (Ibs)
Mass In Sol 1 (Ibs)
Total Mass (Ibs)
Heptachlor
0.06
9.82
0.00
0.00
0.32
164.0
300
1,400
Cyanide
689
6,370
17
0.00
742
9.2
9.2
45.0
0.000278 3.5
216
0.008
5.70
5.708
0.008
0.00
0.008
0.008
0.00
0.008
197
916
3,680
4,596
916
1,330
2,246
640
930
1,570
Tetra-
chloro-
ethene
92.43
976
0.00
0.00
0.00
10.6
3.0
15.0
0.8
116
12.8
563
575.8
12.8
17
29.8
4.1
17
21.1
2-Nltro-
phenol
17,428
0.00
77
0.00
0.00
0.00
0.21
2.00
13.4
1,300
2,420
0.00
2,420
2,420
0.00
2,420
48
0.00
48
2,4,6-Trl-
chloro-
phenol
118
0.00
0.00
0.00
0.00
0.00
1.10
6.29
1.2
98
16
0.00
16
16
0.00
16
1.92
0.00
1.92
Ch 1 oro-
metnane
M.27
0.00
0.00
0.00
0.00
0.00
0.36
2.70
0.19
75
2
0.00
2
2
0.00
2
0.10
0.0
0.10
Vinyl
chloride
31.7
0.00
0.00
0.00
0.00
0.00
0.93
5.50
2
16
4.4
0.00
4.4
4.4
0.00
4.4
0.00
0.00
0.00
2,4-DI-
chloro
phenol
3.81
164.39
0.00
0.00
0.00
43.1
0.42
3.00
0.3
13
0.53
95
95.53
0.53
45
45.53
0.03
2.70
2.73
Penta-
chloro-
phenol
18.76
0.00
0.00
0.00
0.00
0.00
10.20
50.00
3.2
5.9
2.6
0.00
2.6
2.6
0.00
2.6
1.82
0.00
1.82
1,1,2-Trl-
chloro-
ethane
2.47
0.00
0.00
0.00
0.00
0.00
2.37
12.4
0.6
4.1
0.34
0.00
0.34
0.34
0.00
0.34
0.00
0.00
0.00
1,1,2-Trl-
chloro-
ethane
18,904
2,400
1,047
0.00
0.00
0.127
0.43
3.07
18,000
1.1
2,790
1,390
4,180
2,790
83
2,873
112
3.3
115.3
Toluene
2,324
6,800
332
0.00
0.00
2.93
1.38
7.63
14,300
0.16
382
3,930
4,312
382
3,380
3,762
150
1,350
1,500
-------
Groundwater
contaminant area of site zone soil
mass for = (421,250 ft2) X thickness X porosity
Zone A (Ibs) (ft) (0.35)
weight of average containment
water X concentration in Zone A
(62.4 lb/ft3) (ppb) x 10-9
The total contaminant mass in the soil for each contaminant is
listed in Line 12 on Table A-16. These data were calculated using the
following equation:
Soil
contaminant = area of site X average depth of X
mass (Ibs) (421,250 ft2) soil sampled
(13.7 ft)
weight of soil X soil average site
(100 lb/ft3) history concentration
(Line 2, ppb) x 10-9
Line 13, the sum of Lines 11 and 12, represents the total contaminant
mass for each contaminant at the site. All contaminant mass calcula-
tions are based on concentration values as reported by EPA (EPA 1983),
and therefore do not adjust for the sensitivity of laboratory analytical
methods or other factors. To the extent they are included in the
reported values, normal background concentrations are included in the
mass calculations.
Line 14 is the total mass of contaminants in the groundwater after
planned subsurface excavation and material removal. The values in
Line 14 are equivalent to those in Line 11, since the mass of con-
taminant in the groundwater will not be changed significantly by the
excavation program.
As previously discussed, excavation of fill will substantially
reduce the amount of contamination on site; however, not all of the con-
tamination will be removed. To calculate the mass remaining in the soil
after excavation, the fraction of each contaminant remaining was
multiplied by Line 12, the pre-excavation mass. The results are listed
on Line 15. The total mass of each contaminant remaining on site after
excavation was calculated by adding Lines 14 and 15 for each con-
taminant. These values are listed on Line 16.
A-67
-------
Line 17, the mass remaining in the groundwater, was obtained by
multiplying Line 14, the mass of contaminants in the groundwater after
excavation, by the fraction of each contaminant not removed with
flushing. The fraction of contaminant not removed with flushing is
dependent upon the retardation factor (RD, Line 8) and was obtained as
follows: (1) using the contaminant reduction curve presented on Figure
A-6, the percent of contaminant reduction was determined for each con-
taminant based on its retardation factor (expressed as a decimal), and
(2) the value obtained in (1) was subtracted from 1.0.
Line 18, the mass remaining in soil, was similarly calculated:
Line 15, the post-excavation mass in soil, was multiplied by the frac-
tion of each contaminant not removed with flushing.
The total mass of contaminants remaining after flushing, Line 19,
was calculated by adding Lines 17 and 18.
A-6 3
-------
1000
500
100
50
10
Lea<
•
i
•
•
*
*
*
• Aim
V i
X
ninum
»Zinc
Ca<
Jmium
•*,
Nit
;kel •**
***•<
IJolue
"x.(
Methy
le
lene Cl
Ti
rans-1,
2 Dichloroethene
**« • Benzene
Trtehloroethene
•i
>loride
\01, 1, 1-Trichloroethane
8» Chloroform
1 '• 1
«J Phenol
10 20 30
40 50 60 70
Percent Reduction
80 90 100
Not««: (1) RD r Soil retardation coefficient
(2) Reduction* shown ere based on
concentrations remaining In aoll
after proposed flushing
Summary of Contaminant Reduction
FigureA-:
-------
REFERENCES CITED
Bredehoeft, J.D., and G.F. Finder, 1973. Mass transport in flowing
ground water. Water Resources Research, 9.
Chiou, Gary T., et al, 1977. Partition coefficient and bioaccumulation
of selected organic chemicals. Environmental Science and
Technology, Vol II, No. 5, May.
Conway, Richard A. (editor), 1982. Environmental risk analysis for che-
micals. Van Nostrom - Reinhold, New York.
Colder Associates, 1983. Colder groundwater computer package, user and
theory manuals. Seattle, WA.
Matthess, Georg, 1982. The properties of groundwater. John Wiley &
Sons, New York.
Nriagu, Jo 0. (editor), 1980. Zinc in the environment. Wiley Press,
New York.
Perlmutter, N.M. and M. Lieber, 1970. Dispersal of plating waste and
sewage contaminants in ground water and surface water, South
Farmingdale - Massepequa Area, Nassau County, New York. Water
Supply Paper 1879-G, U.S. Geological Survey, Washington, D.C.
U.S. Department of Agriculture, 1973. Soil survey, King County area,
Washington. Soil Conservation Service. Seattle, WA.
U.S. Environmental Protection Agency, 1983. Hazardous waste land treat-
ment. SW-874, Office of Solid Waste and Emergency Response,
Washington, D.C., April.
A-7Q
-------
Appendix B: Summary of Applicable Regulations
-------
APPENDIX B
SUMMARY OF APPLICABLE REGULATIONS
This appendix summarizes regulations of Federal, state, re-
gional, and local agencies that would apply to the potential
remedial action alternatives for cleanup at the Western Pro-
cessing site. Chapter 6 of this feasibility study describes
how these regulations apply to each of the specific alterna-
tives. Standards for contaminant levels that are referred
to in this section, but which are not included in this sec-
tion, are contained in Chapter 2. This appendix contains a
summary of the following regulations:
Federal
Resource Conservation and Recovery Act, 40CFR Parts 260
to 264
National Pollutant Discharge Elimination System
(NPDES), 40 CFR Part 122
National Emissions Standards for Hazardous Pollutants,
40 CFR Part 61
EPA Groundwater Protection Strategy
Implementation of the Uniform Relocation Assistance and
Real Property Acquisition Policies Act of 1970,
40 CFR 4
Intergovernmental Review of Environmental Protection
Agency Programs and Activities, 40 CFR Part 129
Statement of Procedures on Floodplain Management and
Wetlands Protection 40 CFR 6, Appendix A
National Environmental Policy Act (NEPA)
Effluent Guidelines and Standards, CFR 40 Subchapter N
Part 400
Hazardous Materials Regulations, 49 CFR Parts 170
to 179
State
National Pollutant Discharge Elimination System (NPDES)
Permit Program, Chapter 173-220 WAC
Water Quality Standards of the State of Washington,
Chapter 173-201 WAC
B-l
-------
Hydraulics Permit, Chapter 220-110 WAC
State Flood Control Permit, Chapter 508-60 WAC
Washington Industrial Safety and Health Act
Washington State Department of Ecology (WDOE) Final
Cleanup Policy, July 10, 1984
Dangerous Waste Regulations, Chapter 173-303 WAC
Washington State Implementation Plan, Puget Sound Air
Pollution Control Agency (PSAPCA)
Regional
Industrial Waste Discharge Permit and Discharge Limita-
tions, Metro
Regulation I and Regulation II of the Puget Sound Air
Pollution Control Agency
Local
City of Kent Ordinances, Regulations, and Permit
Approvals
FEDERAL
RESOURCE CONSERVATION AND RECOVERY ACT, 40 CFR, PARTS 260 TO
264
CERCLA specifically requires (in Section 104(c)(3)(B)) that
hazardous substances from removal actions be disposed at
facilities in compliance with Subtitle C of the Solid Waste
Disposal Act and which are acceptable to the President
(EPA). CERCLA makes no statement, however, on requirements
of other environmental laws when the selected CERCLA remedy
is not a removal. To address this issue, EPA has formulated
a policy that requires examination of CERCLA remedies (both
removal and nonremoval) in light of applicable and relevant
standards of other environmental laws. Recognizing that
RCRA is often the most relevant of the other laws in remedial
actions, EPA has issued guidance that at least one RCRA-
compliant alternative be considered in CERCLA feasibility
studies.
There are four major technical requirements under RCRA which
are pivotal in the following analyses of selected CERCLA
remedial measures. Those requirements are:
o Closure performance standard (as specified in
40 CFR 264.111)
B-2
-------
o Groundwater protection standard (as specified in
40 CFR 264.92)
o Point of compliance (as specified in 40 CFR
264.95)
o Design requirements
Landfills (as specified in 40 CFR 264.301)
The regulatory language and technical implications for each
requirement are as follows.
CLOSURE PERFORMANCE STANDARD
40 CFR 264.111 states:
The owner or operator must close the facility in
a manner that:
(a) Minimizes the need for further maintenance,
and
(b) Controls, minimizes or eliminates, to the
extent necessary to prevent threats to human
health and the environment, post-closure escape of
hazardous waste, hazardous waste constituents,
leachate, contaminated rainfall, or waste decompo-
sition products to the ground or surface waters or
to the atmosphere.
These requirements clearly preclude any closure of a regu-
lated facility which leaves waste in the ground without a
durable, engineered barrier or containment system. Further,
agency interpretation concludes that in cases of landfills
(or soils where hazardous contaminants are present) an engi-
neered cap must be part of that system. Additional guidance
has also been issued "that such a cap must have at least a
synthetic layer, a drainage layer, and a vegetative support
layer. (Notwithstanding the much more loosely stated re-
quirement of 40 CFR 264.310 (a) (5) which states the cap must
have a permeability less than or equal to any bottom liner
or natural subsoils present.) All these layers together
must be specified, sized, and sloped to minimize short- and
long-term maintenance.
Alternatively, one can meet the closure performance standard
by removing all hazardous waste and waste constituents from
the facility. Historically, EPA has interpreted this
removal to be complete when contaminant levels reach "back-
ground" for the area in question.
The fact that 264.11 is noted as a performance standard also
implies that if, for any reason, the cap or other closure
system fails, noncompliance is automatic. A remedy would be
required to return to RCRA compliance.
B-3
-------
GROUNDWATER PROTECTION STANDARD AND POINT OF COMPLIANCE
40 CFR 264.92 states:
The owner or operator must comply with condi-
tions specified in the facility permit that are
designed to ensure that hazardous constituents
under § 264.93 entering the groundwater from a
regulated unit do not exceed the concentration
limits under § 264.94 in the uppermost aquifer
underlying the waste management area beyond the
point of compliance under § 264.95 during the com-
pliance period under § 264.96. The Regional Admin-
istrator will establish this groundwater protec-
tion standard in the facility permit when hazard-
ous constituents have entered the groundwater from
a regulated unit.
Sections 264.93 through 264.96 which are cited above read as
follows:
§ 264.93 Hazardous constituents.
(a) The Regional Administrator will specify in
the facility permit the hazardous constituents to
which the groundwater protection standard of
§ 264.92 applies. Hazardous constituents are con-
stituents identified in Appendix VIII of Part 261
of this chapter that have been detected in ground-
water in the uppermost aquifer underlying a regu-
lated unit and that are reasonably expected to be
in or derived from waste contained in a regulated
unit, unless the Regional Administrator has ex-
cluded them under paragraph (b) of this section.
(b) The Regional Administrator will exclude an
Appendix VIII constituent from the list of hazard-
ous constituents specified in the facility permit
if he finds that the constituent is not capable of
posing a substantial present or potential hazard
to human health or the environment. In deciding
whether to grant an exemption, the Regional
Administrator will consider the following:
(I) Potential adverse effects on groundwater
quality, considering:
(i) The physical and chemical characteristics
of the water in the regulated unit, including its
potential for migration;
(ii) The hydrogeological characteristics of the
facility and surrounding land;
(iii) The quantity of groundwater and the di-
rection of groundwater flow;
(iv) The proximity and withdrawal rates of
groundwater users;
B-4
-------
(v) The current and future uses of groundwater
in the area;
(vi) The existing quality of groundwater, in-
cluding other sources of contamination and their
cumulative impact on the groundwater quality;
(vii) The potential for health risks caused by
human exposure to waste constituents;
(viii) The potential damage to wildlife, crops,
vegetation, and physical structures caused by ex-
posure to waste constituents;
(ix) The persistence and permanence of the po-
tential adverse effects; and
(2) Potential adverse effects on hydraulically-
connected surface water quality, considering:
(i) The volume and physical and chemical char-
acteristics of the waste in the regulated unit;
(ii) The hydrogeological characteristics of the
facility and surrounding land;
(iii) The quantity and quality of groundwater,
and the direction of groundwater flow;
(iv) The patterns of rainfall in the region;
(v) The proximity of the regulated unit to sur-
face waters;
(vi) The current and future uses of surface
waters in the area and any water quality standards
established for those surface waters;
(vii) The existing quality of surface water,
including other sources of contamination and the
cumulative impact on surface-water quality;
(viii) The potential for health risks caused by
human exposure to waste constituents;
(ix) The potential damage to wildlife, crops,
vegetation, and physical structures caused by ex-
posure to waste constituents; and
(x) The persistence and permanence of the po-
tential adverse effects.
(c) In making any determination under para-
graph (b) of this section about the use of ground-
water in the area around the facility, the Regional
Administrator will consider any identification of
underground sources of drinking water and exempted
aquifers made under § 144.8 of this chapter.
§ 264.94 Concentration limits.
(a) The Regional Administrator will specify in
the facility permit concentrations limits in the
groundwater for hazardous constituents established
under § 264.93. The concentration of a hazardous
constituent:
(1) Must not exceed the background level of the
constituent in the groundwater at the time that
limit is specified in the permit; or
B-5
-------
(2) For any of the constituents listed in
Table B-l, must not exceed the respective value
given in that Table if the background level of the
constituent is below the value given in Table B-l;
or
Table B-l
MAXIMUM CONCENTRATION OF CONSTITUENTS
FOR GROUNDWATER PROTECTION
Constituent
Arsenic
Barium
Cadmium
Chromium
Lead
Mercury
Selenium
Silver
Endrin (1,2,3,4,10, 10-hexachloro-l,7-epoxy-
1,4,41,5,6,7,8,9a-octahydro-l, 4-endo,
endo-5,8-dimethano naphthalene)
Lindane (1,2,3,4,5,6-hexachlorocyclohexane,
gamma isomer)
Methoxychlor (1,1,l-Trichloro-2,2-bis
(p-methoxyphenylethane)
Toxaphene (C H Cl , Technical chlorinated
camphene, 67-69 percent chlorine)
2,4-D (2,4-Dichlorophenoxyacetic acid)
2,4,5-TP Silvex (2,4,5-Trichlorophenox
propionic acid)
Maximum
Concentra-
tion
(milli-
gram/
liter)
0.05
1.0
0.01
0.05
0.05
0.002
0.01
0.05
0.0002
0.004
0.1
0.005
0.1
0.01
(3) Must not exceed an alternate limit estab-
lished by the Regional Administrator under para-
graph (b) of this section.
(b) The Regional Administrator will establish
an alternate concentration limit for a hazardous
constituent if he finds that the constituent will
not pose a substantial present or potential hazard
to human health or the environment as long as the
alternate concentration limit is not exceeded. In
establishing alternate concentration limits, the
Regional Administrator will consider the following
factors:
B-6
-------
(1) Potential adverse effects on groundwater
quality, considering:
(i) The physical and chemical characteristics
of the waste in the regulated unit, including its
potential for migration;
(ii) The hydrogeological characteristics of the
facility and surrounding land;
(iii) The quantity of groundwater and the direc-
tion of groundwater flow;
(iv) The proximity and withdrawal rates of
groundwater users;
(v) The current and future uses of groundwater
in the area;
(vi) The existing quality of groundwater,
including other sources of contamination and their
cumulative impact on the groundwater quality;
(vii) The potential for health risks caused by
human exposure to waste constituents;
(viii) The potential damage to wildlife, crops,
vegetation, and physical structures caused by ex-
posure to waste constituents;
(ix) The persistence and permanence of the po-
tential adverse effects; and
(2) Potential adverse effects on hydraulically-
connected surface-water quality, considering:
(i) The volume and physical and chemical char-
acteristics of the waste in the regulated unit;
(ii) The hydrogeological characteristics of the
facility and surrounding land;
(iii) The quantity and quality of groundwater,
and the direction of groundwater flow;
(iv) The patterns of rainfall in the region;
(v) The proximity of the regulated unit to sur-
face waters;
(vi) The current and future uses of surface
waters in the area and any water quality standards
established for those surface waters;
(vii) The existing quality of surface water,
including other sources of contamination and the
cumulative impact on surface water quality;
(viii) The potential for health risks caused by
human exposure to waste constituents;
(ix) The potential damage to wildlife, crops,
vegetation, and physical structures caused by ex-
posure to waste constituents; and
(x) The persistence and permanence of the
potential adverse effects.
(c) In making any determination under para-
graph (b) of this section about the use of ground-
water in the area around the facility the Regional
Administrator will consider any identification of
underground sources of drinking water and exempted
aquifers made under § 144.8 of this chapter.
B-7
-------
§ 264.95 Point of compliance.
(a) The Regional Administrator will specify in
the facility permit the point of compliance at
which the groundwater protection standard of
§ 264.92 applies and at which monitoring must be
conducted. The point of compliance is a vertical
surface located at the hydraulically downgradient
limit of the waste management area that extends
down into the uppermost aquifer underlying the
regulated units.
{b) The waste management area is the limit pro-
jected in the horizontal plane of the area on
which waste will be placed during the active life
of a regulated unit.
(1) The waste management area includes horizon-
tal space taken up by any liner, dike, or other
barrier designed to contain waste in a regulated
unit.
(2) If the facility contains more than one reg-
ulated unit, the waste management area is
described by an imaginary line circumscribing the
several regulated units.
§ 264.96 Compliance period.
(a) The Regional Administrator will specify in
the facility permit the compliance period during
which the groundwater protection standard of
§ 264.92 applies. The compliance period is the
number of years equal to the active life of the
waste management area (including any waste manage-
ment activity prior to permitting, and the closure
period.)
(b) The compliance period begins when the owner
or operator initiates a compliance monitoring pro-
gram meeting the requirements of § 264.99.
(c) If the owner or operator is engaged in a
corrective action program at the end of the com-
pliance period specified in paragraph (a) of this
section, the compliance period is extended until
the owner or operator can demonstrate that the
groundwater protection standard of § 264.92 has
not been exceeded for a period of three consecu-
tive years.
In short. Sections 264.92 through 264.96 require that the
owner or operator of a RCRA-regulated facility not contami-
nate groundwater at the point of compliance beyond concen-
tration limits set by the Regional Administrator. (Usually,
background determines the limits.) Further,- the owner or
operator must prove that he is meeting the established con-
centration limits by instituting a groundwater monitoring
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program at the "point of compliance." A point of compliance
is really a perimeter around a waste management unit or
units (grouped together). This perimeter extends downward
vertically into the groundwater body and monitoring must
take place here. If established concentration limits are
exceeded at this point of compliance, corrective action must
be initiated.
These RCRA requirements are analogous to the CERCLA issue of
"How clean is clean?"
DESIGN REQUIREMENTS—LANDFILLS
40 CFR 264.301 states:
(a) A landfill (except for an existing portion
of a landfill) must have:
(1) A liner that is designed, constructed, and
installed to prevent any migration of wastes out
of the landfill to the adjacent subsurface soil or
groundwater or surface water at anytime during the
active life (including the closure period) of the
landfill. The liner must be constructed of mate-
rials that prevent wastes from passing into the
liner during the active life of the facility- The
liner must be:
(i) Constructed of materials that have appro-
priate chemical properties and sufficient strength
and thickness to prevent failure due to pressure
gradients (including static head and external hy-
drogeologic forces), physical contact with the
waste or leachate to which they are exposed, cli-
matic conditions, the stress of installation, and
the stress of daily operation;
(ii) Placed upon a foundation or base capable
of providing support to the liner and resistance
to pressure gradients above and below the liner to
prevent failure of the liner due to settlement,
compression, or uplift; and
(iii) Installed to cover all surrounding earth
likely to be in contact with the waste or leach-
ate; and
(2) A leachate collection and removal system
immediately above the liner that is designed, con-
structed, maintained, and operated to collect and
remove leachate from the landfill. The Regional
Administrator will specify design and operating
conditions in the permit to ensure that the leach-
ate depth over the liner does not exceed 30 cm
(one foot). The leachate collection and removal
system must be:
(i) Constructed of materials that are:
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(A) Chemically resistant to the waste managed
in the landfill and the leachate expected to be
generated; and
(B) Of sufficient strength and thickness to
prevent collapse under the pressures exerted by
overlying wastes, waste cover materials, and by
any equipment used at the landfill; and
(ii) Designed and operated to function without
clogging through the scheduled closure of the
landfill.
(b) The owner or operator will be exempted from
the requirements of paragraph (a) of this section
if the Regional Administrator finds, based on a
demonstration by the owner or operator, that al-
ternative design and operating practices, together
with location characteristics, will prevent the
migration of any hazardous constituents
(see § 264.93) into the groundwater or surface
water at any future time. In deciding whether to
grant an exemption, the Regional Administrator
will consider:
(1) The nature and quantity of the wastes;
(2) The proposed alternate design and opera-
t ion ;
(3) The hydrogeologic setting of the facility,
including the attenuative capacity and thickness
of the liners and soils present between the land-
fill and groundwater or surface water; and
(4) All other factors which would influence the
quality and mobility of the leachate produced and
the potential for it to migrate to groundwater or
surface water.
(c) The owner or operator must design, con-
struct, operate, and maintain a run-on control
system capable of preventing flow onto the active
portion of the landfill during peak discharge from
at least a 25-year storm.
(d) The owner or operator must design, con-
struct,- operate, and maintain a run-off management
system to collect and control at least the water
volume resulting from a 24-hour, 25-year storm.
(e) Collection and holding facilities (e.g.,
tanks or basins) associated with run-on and run-
off control systems must be emptied or otherwise
managed expeditiously after storms to maintain
design capacity of the system.
(f) If the landfill contains any particulate
matter which may be subject to wind dispersal, the
owner or operator must cover or otherwise manage
the landfill to control wind dispersal.
(g) The Regional Administrator will specify in
the permit all design and operating practices that
are necessary to ensure that the requirements of
this section are satisfied.
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The obvious intent of the above regulations is that new haz-
ardous waste landfills be lined and have a leachate collec-
tion system. However the parenthetical statement in para-
graph (a) "except for an existing portion of a landfill" is
key to many CERCLA actions. This statement was included in
the regulations is because it was recognized that unearthing
large volumes of already buried hazardous waste might pre-
sent more undesirable effects than securing it (to the
largest degree possible) in place. Thus RCRA does allow for
leaving buried hazardous waste in place without meeting the
above-cited design standards. It should be noted, however,
that the other technical standards of RCRA must be ade-
quately addressed and that if the material is unearthed for
the purpose of being land disposed the design standards do
apply. Additionally, if the material is unearthed for
treatment or another form of disposal the pertinent RCRA
regulations apply fully for that treatment or disposal.
In studying the RCRA implications for each alternative it
must be remembered that RCRA was not formulated with reme-
dial actions in mind; consequently some interpretations of
applicability (or nonapplicability) are open to debate. The
basis for the interpretations presented here are taken
largely from the memorandum titled: "CERCLA Compliance With
the Requirements of Other Environmental Statutes" issued by
Lee M. Thomas, U.S. EPA Assistant Administrator.
Note 1: In all cases where hazardous wastes are being
transported away from the Western Processing site
for treatment or disposal all the current RCRA
regulations (for generation, transportation, and
disposal) and the requirements of the 1984 Amend-
ments to the Solid Waste Disposal Act must be con-
sidered. Further, DOT regulations as appropriate
are applicable.
The 1984 amendments have significant requirements
for land disposal facilities that become effective
at 6 and 12 months (and several later) from the
date of enactment. The amendments were signed in
November of 1984.
Note 2: In the case where a remedial action is undertaken
by the EPA, that agency must assume generator re-
sponsibility. In the case where a remedial action
is undertaken by the PRP's, that group (or a rep-
resentative of that group) must assume generator
responsibility.
Note 3: The U.S. EPA has published guidance documents for
design and installation of caps for hazardous
waste landfills. This guidance is substantially
more specific than the general regulatory
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requirements and is not at all performance
oriented. Deviations in cap design from published
guidance might well meet the regulatory perform-
ance standard but put EPA in the position of
justifying doing something other than it recom-
mends in its own guidance.
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES),
40 CFR PART 122
Discharge of treated water from the site into Mill Creek
will require an NPDES permit. The NPDES permit program es-
tablishes effluent guidelines and standards of pretreatment
for new and existing sources. Compliance with the NPDES
permit constitutes compliance with Sections 301, 302, 306,
307, 318, 403, and 405 of the Clean Water Act (CWA) except
for any toxic effluent standards and prohibitions imposed
under Section 307 CWA. Table 2-1 (Chapter 2) shows the
toxic pollutant effluent standards and water quality cri-
teria adopted under CWA Section 304 as set forth in 40 CFR
part 129 and in the Federal Register, November 28, 1980.
The Washington State Department of Ecology (WDOE) has been
authorized to administer the NPDES program. The state is
required to conduct the program in accordance with the Fed-
eral NPDES program but is not precluded from adopting or
enforcing requirements which are more stringent or more ex-
tensive. The State-adopted NPDES program is discussed in
this appendix.
NATIONAL EMISSIONS STANDARDS FOR HAZARDOUS POLLUTANTS,
40 CFR PART 61
The provisions of this part apply to the owner or operator
of any stationary air emissions source for which a standard
is prescribed under this part. This part establishes
emission standards for asbestos, beryllium, mercury, and
vinyl chloride. Owners and operators of facilities which
emit these pollutants are prohibited from operating any new
source in violation of these standards. They are required
to submit to the EPA technical information including
calculations of emissions estimates and provide facilities
for testing emissions following construction of the source.
EPA GRQUNDWATER PROTECTION STRATEGY
The Groundwater Protection Strategy (GWPS) has been deve-
loped by EPA to increase state and Federal capability for
coping with groundwater problems and to improve the coher-
ence and consistency of EPA programs dealing with ground-
water. The objective of the GWPS that is most likely to
affect remedial action at the Western Processing site is the
adoption of guidelines which would define appropriate
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protection strategies for different classes of aquifers.
The three classes of aquifers are:
Class I, Special Groundwaters—those which are
highly vulnerable to contamination and are charac-
terized as either irreplaceable sources of drink-
ing water or ecologically vital.
Class II, Current and Potential Sources of
Drinking Water—all other groundwaters that are
currently used or potentially available for
drinking water.
Class III, Groundwater not a potential source of
drinking water and of limited beneficial use--
groundwaters that are saline or otherwise contam-
inated beyond reasonable use as drinking water or
other beneficial purposes. In addition, the ground-
water must not be connected to Class I or Class II
groundwater or to surface water in a way that
would allow contaminants to migrate to these
waters and potentially cause adverse effects on
human health or the environment.
Under this ruling, the degree of cleanup and/or protection
of groundwater resources to be achieved is generally keyed
to the classification of the affected or potentially affect-
ed aquifer. Cleanups at sites which lie over Class I, Spe-
cial Groundwaters, will be to drinking water standards or
background levels, as appropriate. In unusual cases, clean-
up to a less stringent level may be considered if the alter-
native would not:
o Preclude fund-balancing
o Be technically infeasible
o Cause unacceptable environmental impacts
o Constitute a final cleanup but rather an
interim measure
o Create overriding public health concerns at
an enforcement site
For remedial actions at sites over current or potential
sources of drinking water (Class II groundwaters), the goal
of CERCLA cleanups is drinking water quality and background
levels, as appropriate, with allowance for modifications
based upon the factors cited above. The exemptions are ap-
plied less stringently for potential sources of drinking
water (Class II) as compared to current sources of drinking
water (Class I).
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For CERCLA sites located over groundwaters which are not
considered potential sources of drinking water (Class III
groundwaters), CERCLA remedial actions will generally not
involve groundwater cleanup. The priority of these sites
for remedial action implementation is low, in the absence of
other hazards to human health and the environment (e.g.,
surface water contamination, fire, or explosion).
Groundwater at the Western Processing site is classified as
Class II. Based on this policy, the cleanup goal for the
site would be drinking water quality or background levels.
IMPLEMENTATION OF THE UNIFORM RELOCATION ASSISTANCE AND REAL
PROPERTY ACQUISITION POLICIES ACT OF 1970, 40 CFR 4
This part applies to EPA projects and to EPA-assisted proj-
ects which cause the displacement of persons or the acquisi-
tion of real property- It may be necessary to acquire prop-
erty off the Western Processing site for construction of the
wells, cap, or treatment plant, or to remove offsite contami-
nants. If EPA acquires offsite property, it is required to
provide the current owner with just compensation disregarding
any decrease or increase in the value of the property caused
by the project. The compensation must be based on the fair
market value of the property and it cannot be less than the
approved appraised value of the property.
INTERGOVERNMENTAL REVIEW OF ENVIRONMENTAL PROTECTION AGENCY
PROGRAMS AND ACTIVITIES, 40 CFR PART 29
These regulations implement Executive Order 12372. The
stated purpose of the regulations is:
To foster an intergovernmental partnership and a
strengthened Federalism by relying on state processes
and on state, areawide, regional, and local coordina-
tion for review of proposed federal financial assis-
tance and direct federal development.
The regulations authorize adoption by the states of a pro-
cess to review and coordinate proposed federal developments.
If a state adopts such a process, EPA is required, to the
extent permitted by law, to:
o Use the state process to determine official views
of state and local elected officials.
o Communicate with state and local elected officials
as early in a program planning cycle as is reason-
ably feasible to explain specific plans and
actions
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o Make efforts to accommodate state and local elect-
ed officials' concerns with proposed federal
financial assistance and direct federal develop-
ment
In addition to communication with the state agency, the EPA
is required, to the extent practicable, to consult with and
seek advice from all other substantially affected federal
departments and agencies in an effort to assure full coordi-
nation between such agencies and EPA.
At this time, an intergovernmental review process for the
Western Processing site cleanup has not been adopted. If
site cleanup is funded with federal or state funds or
through a cooperative agreement, then an intergovernmental
review process will be established by the state. The review
process will be established by the State Office of Planning
and Community Affairs.
STATEMENT OF PROCEDURES ON FLOODPLAIN MANAGEMENT AND
WETLANDS PROTECTION 40 CFR 6, APPENDIX A
Executive Order 11988, entitled "Floodplain Management" and
dated May 24, 1977, requires federal agencies to evaluate
the potential effects of actions it may take in a flood-
plain. The purpose is to avoid wherever possible adversely
impacting floodplains, and to ensure that its planning pro-
grams and budget requests reflect consideration of flood
hazards and floodplain management. Executive Order 11990,
entitled "Protection of Wetlands" and dated May 24, 1977,
requires federal agencies to take action to avoid adversely
impacting wetlands wherever possible, to minimize wetlands
destruction, to preserve the values of wetlands, and to pre-
scribe procedures to implement the policies and procedures
of this Executive Order.
In order to determine whether an action will be located in
or affect a floodplain or wetlands, the agency must use the
Federal Insurance Administration maps showing flood hazard
boundaries. The majority of the Western Processing site is
not designated as a flood hazard area. Areas designated as
flood hazard areas are along the Mill Creek channel and the
drainage ditches along the eastern and southern edges of the
property.
The site does not include wetlands designated by the Fish
and Wildlife Service.
To the extent that the remedial actions require acquiring
land or constructing improvements in the designated flood
hazard areas, the regulations require that the agency incor-
porate floodplain management goals and wetlands protection
considerations into its planning, regulatory, and decision-
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making processes. It shall also promote the preservation
and restoration of floodplains so that their natural and
beneficial values can be realized. To the extent possible
EPA shall:
1. Reduce the hazard and risk of flood loss and,
wherever it is possible, avoid direct or indirect
adverse impact on floodplains
2. Where there is no practical alternative to loca-
ting in a floodplain, minimize the impact of
floods on human safety, health, and welfare, as
well as the natural environment
3. Restore and preserve natural and beneficial values
served by floodplains
4. Require the construction of EPA structures and
facilities to be in accordance with the standards
and criteria of the regulations promulgated pur-
suant to the National Flood Insurance Program
NATIONAL ENVIRONMENTAL POLICY ACT (NEPA)
Superfund-financed remedial actions are generally exempt
from NEPA requirements to prepare an environmental impact
statement (EIS). This is based on numerous court decisions
that found that the agency carries out the functional equiv-
alent of a NEPA review in its permitting and regulatory ac-
tivities. Under this exemption, the EPA is not obligated to
comply with formal EIS procedures if two criteria are met.
The first criterion is that the authorizing statute (i.e.,
CERCLA) must provide substantive and procedural standards to
ensure full and adequate consideration of environmental
issues and alternatives. The second criterion is that the
public must be afforded an opportunity for participation in
the evaluation of environmental factors and alternatives
prior to arriving at a final decision.
Performance of the following steps is expected to ensure
that fund-financed remedial actions meet these criteria and
achieve functional equivalency with EIS requirements:
1. The process for determining the appropriate extent
of remedy required by CERCLA section 105(3) and
described in Section 300.68 of the NCP must be
followed. To meet the first criterion of NEPA
functional equivalency, this process embodies the
necessary and appropriate investigation and
analysis of environmental factors as they specif-
ically relate to a Superfund site and alternatives
that are being considered to correct the
situation.
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2. To meet the second criterion, a meaningful oppor-
tunity for public comment on environmental issues
must be provided prior to the final selection of a
remedial alternative. To meet this requirement,
EPA regions must allow both the opportunity and
adequate time for the public to review draft fea-
sibility studies. This should be accomplished as
part of the community relations program that is
required at all Superfund response sites.
EFFLUENT GUIDELINES AND STANDARDS; 40 CFR SUBCHAPTER N
PART 403
These regulations prescribe effluent limitations guidelines
for existing sources, standards of performance for new
sources, and pretreatment standards for new and existing
sources pursuant to the Clean Water Act. The regulations
apply specifically to: (1) pollutants from non-domestic
sources covered by pretreatment standards which are dis-
charged into publicly-owned treatment works (POTWs), and
(2) any new or existing source subject to pretreatment
standards.
Water discharged from the Western Processing site into the
Metro sewer system would be subject to the pretreatment
standards and therefore must also comply with the effluent
guidelines and standards established under this section.
Metro has been given the authority and has established ef-
fluent standards which comply with 40 CFR Part 400. These
are discussed in this appendix under "Regional."
HAZARDOUS MATERIALS REGULATIONS; 49 CFR PARTS 170 TO 179
These regulations are administered by the U.S. Department of
Transportation.
All interstate transport of hazardous materials must be con-
ducted according to the provisions of 49 CFR Parts
170 to 179. These regulations apply to the transport of
hazardous materials via all carriers (e.g., air- motor ve-
hicle, rail) and to the packaging and reporting procedures
required. Intrastate transport via motor vehicle is regu-
lated by WDOE's Dangerous Waste Regulations, WAC 173-303.
Transport of hazardous wastes from the Western Processing
site to Arlington, Oregon, or any other regulated offsite
disposal facility outside Washington state would be regulat-
ed under the federal regulations. The Washington State Uti-
lities and Transportation Commission and the Washington State
Patrol follow the federal regulations and the WDOE regulations
in controlling the transportation of hazardous materials.
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STATE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES)
PERMIT PROGRAM, CHAPTER 173-220 WAG
WDOE is authorized to administer the NPDES permit program as
set forth in the Federal Water Pollution Control Act based
on the authority granted to WDOE by RCW 90.48, Water Pol-
lution Control. The purpose of the permit program is to
regulate the discharge of pollutants, wastes, or other sub-
stances from point sources into navigable water. Discharge
of treated groundwater into Mill Creek or the Green River
will require an NPDES permit.
Chapter 173-200 WAC does not establish effluent limitations
or water quality standards. The regulation does, however,
require that the effluent standards set forth in the FWPCA
are met where applicable. On this subject. Chapter 173-220
states the following:
WAC 173-220-130 Effluent limitations, water quality
standards, and other requirements for permits.
(1) Any permit issued by the department shall apply
and insure compliance with all of the following,
whenever applicable:
(a) Effluent limitations under Sections 301, 302,
306, and 307 of the FWPCA. The effluent lim-
itations shall not be less stringent than
those based upon the treatment facility
design efficiency contained in approved engi-
neering plans and reports or approved revi-
sions thereto. The effluent limits shall
reflect any seasonal variation in industrial
loading.
(b) Any more stringent limitation, including
those:
(i) Necessary to meet water quality stan-
dards, treatment standards or schedules
of compliance established pursuant to
any state law or regulation under au-
thority preserved to the state by Sec-
tion 510 of the FWPCA; or
(ii) Necessary to meet any federal law or
regulation other than the FWPCA or regu-
lations thereunder; or
(iii) Required to implement any applicable
water quality standards; such
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limitations to include any legally
applicable requirements necessary to
implement total maximum daily loads
established pursuant to section 303(d)
and incorporated in the continuing
planning process approved under sec-
tion 303 (e) of the FWPCA and any regula-
tions and guidelines issued pursuant
thereto;
(iv) Necessary to prevent or control pollu-
tant discharges from plant site runoff,
spillage or leaks, sludge or waste dis-
posal, or raw material storage;
(v) Necessary to provide all known, avail-
able and reasonable methods of treatment
(c) Any more stringent legal applicable require-
ments necessary to comply with a plan
approved pursuant to section 208 (b) of the
FWPCA; and
(d) Prior to promulgation by the administrator of
applicable effluent standards and limitations
pursuant to sections 301, 302, 306, and 307
of the FWPCA, such conditions as the depart-
ment determines are necessary to carry out
the provisions of the FWPCA
(2) In any case where an issued permit applies the
effluent standards and limitations described in
subparagraph (a) of paragraph (1) of this section,
the department shall make a finding that any dis-
charge authorized by the permit will not violate
applicable water quality standards.
(3) In the application of effluent standards and
limitations, water quality standards and other
legally applicable requirements pursuant to para-
graphs (1) and (2) hereof, each issued permit
shall specify average and maximum daily quantita-
tive (in terms of weight) or other such appropri-
ate limitations for the level of pollutants and
the authorized discharge.
Chapter 173.220 requires that any person proposing a dis-
charge of pollutants into navigable waters submit an NPDES
permit to the WDOE. Based on this initial submission, the
WDOE will make a tentative determination to issue or deny
the permit. If the tentative determination is to issue the
permit, proposed effluent limitations will be established at
that time.
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In order to establish effluent limits, the WDOE uses the
toxic pollutant effluent standards (40 CFR Part 129) and the
Water Quality Criteria (Federal Register, November 28, 1980)
for 64 toxic pollutants. For those pollutants contained in
a proposed discharge that are not identified in the above
sources, WDOE would research other published data to deter-
mine effluent limits.
WATER QUALITY STANDARDS FOR WATERS OF THE STATE OF
WASHINGTON, CHAPTER 173-201 WAG
The purpose of this regulation is to establish surface water
quality standards and classifications for surface waters of
the state pursuant to the provisions of Chapter 90.48 RCW.
Mill Creek is in the water quality criteria Class A (excel-
lent) . Waters in this class are characterized as follows:
WAC 173-201-045 general water use and criteria classes
Class A (excellent)
(a) General characteristic. Water quality of this
class shall meet or exceed the requirements for all or
substantially all uses.
(b) Characteristic uses. Characteristic uses shall
include, but not be limited to, the following:
(i) Water supply (domestic, industrial, agricul-
tural)
(ii) Stock watering
(iii) Fish and shellfish:
Salmonid migration, rearing, spawning, and
harvesting
Other fish migration, rearing, spawning, and
harvesting
Clam, oyster, and mussel rearing, spawning,
and harvesting
Crustaceans and other shellfish (crabs,
shrimp, crayfish, scallops, etc.) rearing,
spawning, and harvesting
(iv) Wildlife habitat
(v) Recreation (primary contact recreation, sport
fishing, boating, and aesthetic enjoyment)
(vi) Commerce and navigation
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(c) Water quality criteria
(i) Fecal coliform organisms
Freshwater—Fecal coliform organisms shall
not exceed a geometric mean value of 100 or-
ganisms/100 mL, with not more than 10 percent
of samples exceeding 200 organisms/100 mL
(ii) Dissolved oxygen
Freshwater—Dissolved oxygen shall exceed
8.0 mg/L
(iii) Total dissolved gas shall not exceed 110 per-
cent of saturation at any point of sample
collection
(iv) Temperature shall not exceed 18.0 degrees C
(freshwater) due to human activities. Tem-
perature increases shall not, at any time,
exceed t=28/(T+7) (freshwater).
When natural conditions exceed 18.0 degrees C
(freshwater) no temperature increase will be
allowed which will raise the receiving water
temperature by greater than 0.3 degrees C.
For purposes hereof, "t" represents the per-
missive temperature change across the dilu-
tion zone; and "T" represents the highest
existing temperature in this water classi-
fication outside of any dilution zone.
Provided that temperature increase resulting
from nonpoint source activities shall not
exceed 2.8 degrees C, and the maximum water
temperature shall not exceed 18.3 degrees C
(freshwater).
(v) pH shall be within the range of 6.5 to
8.5 (freshwater) or 7.0 to 8.5 (marine water)
with a man-caused variation within a range of
less than 0.5 units.
(vi) Turbidity shall not exceed 5 NTU over back-
ground turbidity when the background turbi-
dity is 50 NTU or less, or have more than a
10 percent increase in turbidity when the
background turbidity is more than 50 NTU.
(vii) Toxic, radioactive, or deleterious material
concentrations shall be below those of public
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health significance, or which may cause acute
or chronic toxic conditions to the aquatic
biota, or which may adversely affect any
water use.
(vii) Aesthetic values shall not be impaired by the
presence of materials or their effects, ex-
cluding those of natural origin, which offend
the senses of sight, smell, touch, or taste.
Generally, waste discharge permits issued pursuant to the
NPDES program are conditioned to authorize discharges which
meet the water quality standards for a particular stream
classification. This is consistent with the antidegradation
policy of the state as guided by Chapter 90.48 RCW. How-
ever, WAC 173-201-035(8) states:
(d) Whenever the natural conditions of said waters are
of a lower quality than the criteria assigned, the
natural conditions shall constitute the water
quality criteria.
(e) The criteria and special conditions established in
WAC 173-201-045 through 173-201-085 may be modi-
fied for a specific water body on a short-term
basis when necessary to accommodate essential ac-
tivities, respond to emergencies, or to otherwise
protect the public interest. Such modification
shall be issued in writing by the director or his
designee subject to such terms and conditions as
he may prescribe.
(f) In no case, will any degradation of water quality
be allowed if this degradation interferes with or
becomes injurious to existing water uses and
causes long-term and irreparable harm to the
environment.
Section (d) above states that if the existing water quality
is lower than the water quality expected based on the stream
class, then the discharge need only be as good as the exist-
ing water quality in the stream. Also a permit modification
can be requested to temporarily violate the otherwise
applicable standards. However, as stated in (f) above,
water quality degradation is not allowed if it has an
adverse effect on existing water uses or causes long-term
damage to the environment. WAC 173-201-035 (12) states that
deleterions concentrations of toxic or other nonradioactive
materials shall be determined by WDOE in consideration of
the Quality Criteria for Water published by EPA 1976 and as
revised.
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HYDRAULICS PERMIT, CHAPTER 220-110 WAG
A hydraulics permit issued by the Washington State Depart-
ment of Fisheries is required for projects that would use,
divert, obstruct, or change the natural flow or bed of any
river or stream as authorized under RCW 75.20.100. Projects
in Mill Creek that might be proposed as part of the remedial
actions are dredging, temporary diversion, and/or construc-
tion of outfall structures to the creek. The following
regulations of Chapter 220-110 WAC would be used to evaluate
and place conditions on the hydraulics permit:
WAC 220-110-080. CHANNEL CHANGE—TEMPORARY AND PERMA-
NENT. The following technical provisions may apply to
channel change—temporary and permanent projects:
(1) Permanent new channels shall be similar in
length, width, depth, gradient, and meander
configuration as the old channel.
(2) The new channel shall provide fish habitat
similar to that which previously existed in
the old channel.
(3) During construction, the new channel shall be
isolated from the flowing stream by plugs at
the upstream and downstream ends of the new
channel.
(4) Diversion of flow into a new channel shall be
accomplished by: (a) First removing the
downstream plug; (b) removing the upstream
plug; and (c) closing the upstream end of the
old channel.
(5) Filling of the old channel shall begin from
the upstream closure and the fill material
compacted. Water discharging from the fill
shall not adversely impact fish life.
(6) Before water is diverted into a permanent new
channel, the banks shall be armored to pre-
vent erosion.
(7) The angle of the structure used to divert the
water into the new channel shall allow a
smooth transition of water flow.
(8) After completion of the permanent new channel
and filling of the old channel, all unpro-
tected banks shall be revegetated or other-
wise protected to prevent erosion.
B-23
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(9) The applicant shall have fish capture and
transportation equipment ready and on the job
site. Captured fish shall be immediately and
safely transferred to free flowing water.
WAC 220-110-130. DREDGING. The following technical
provisions may apply to dredging projects:
(1) Dredging shall not be conducted in fish
spawning areas.
(2) During the dredging of a lake or pond, a boom
or similar device shall be installed to con-
tain floatable materials.
(3) Dredged bed materials shall be disposed of at
Department of Natural Resources open water
disposal sites or upland sites approved by
the Department.
(4) Dredging shall be conducted with dredge types
that cause the lowest mortality on fish life.
(5) Dredging shall stop when distressed or dead
fish are observed in the work area. The De-
partment shall be notified immediately.
(6) If a hydraulic dredge is used, it shall be
operated with the intake on or below the sur-
face of the material being removed. Reverse
purging of the intake line shall be held to a
minimum.
(7) If a dragline or clamshell is used, it shall
be operated to minimize turbidity. During
excavation, each pass with the clamshell or
dragline bucket shall be complete. Dredged
material shall not be stockpiled in the
water.
(8) Upon completion of the dredging the water-
course bed shall not contain pits, potholes,
or large depressions.
WAC 220-110-170. OUTFALL STRUCTURES. The following
technical provisions may apply to outfall structure
projects:
(1) The outfall structure shall be designed and
constructed to prevent the entry of fish.
(2) The watercourse bank and bed at the point of
discharge shall be armored to prevent
scouring.
B-24
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(3) Excavation for placement of the structure or
armoring materials shall be isolated from the
wetted perimeter.
(4) Alteration or disturbance of banks or bank
vegetation shall be held to a minimum, and
all disturbed areas shall be revegetated or
otherwise protected from erosion.
(5) Structures containing concrete or wood pre-
servatives shall be cured prior to water
encroachment.
These regulations are intended to protect aquatic life and
habitat. They are technical provisions that may be applied
to a project before permit approval is granted. However,
they are not required and are subject to interpretation by
the Department of Fisheries and the Department of Game.
STATE FLOOD CONTROL ZONE PERMIT, CHAPTER 508-60 WAC
Compliance with this regulation is required by WDOE but the
completed permit is submitted to the City of Kent. A flood
control zone permit is required for projects which include
the following:
Construction, operation and maintenance of any works,
structures and improvements, private or public, to be
created or built or to be reconstructed or modified
upon the banks or in or over the channel or over and
across the flood plain or floodway of any stream or
body of water within an established flood control zone.
This permit would apply to the construction of an outfall
into Mill Creek and to the construction of any facilities in
the designated flood control zone. Facilities that might be
constructed at the Western Processing site are a groundwater
treatment plant and a landfill. These facilities would be
described in a flood control zone permit and submitted to
the City of Kent. The City determines whether the structure
lies within the flood control zone, which is the 100-year
flood plain. For those facilities that lie in the flood
control zone, special measures are required in order to pro-
tect structures against flood damage.
Based on the Flood Insurance Study for the City of Kent,
Federal Emergency Management Agency, 1980, the majority of
the site is outside the 100-year flood plain. Mill Creek
and the drainage ditches along the eastern and southern side
of the property have associated floodways that may be con-
sidered to be flood control zones. If these are considered
flood control zones, then flood protection measures may be
required of structures in these areas.
B-25
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WASHINGTON INDUSTRIAL SAFETY AND HEALTH ACT
Health standards applicable to hazardous waste site activity
are contained in Chapter 296-24 WAC, General Safety and
Health Standards, and Chapter 296-62, General Occupational
Health Standards. These regulations require the following:
o An accident prevention program or site safety plan
must be prepared before site activity begins
(WAC 296-24-040).
o A hazard evaluation of the site should identify
known and potential hazards from gases, chemicals,
and other materials, and the safety plan should
instruct workers on safe practices and emergency
actions following accidental exposure
[WAC 296-24-040(iv)].
o Training programs to improve the skill and compe-
tency of the workers should be completed before
work is commenced (WAC 296-24-02).
o Workers are required to use personal protective
equipment, eye and face protection, and should be
instructed in the safe use of respirators for rou-
tine and emergency use (WAC 296-07501, -07801,
-07115).
o Deluge showers and eye wash fountains are required
to be available for emergency operations
(WAC 296-62-130) .
o Operational procedures, training, and signage must
be implemented, and medical surveillance provided
for areas where any of the 14 identified carcino-
gens are present (WAC 296-62-073).
o Personnel requirements and general precautions for
operations in confined areas must be established
(WAC 296-62-145) .
o Operational procedures must be established to
ensure that the permissible exposure limits are
not exceeded for various substances
(WAC 296-62-07005, -0721, -07347, -07517, -080).
These regulations are enforced by WISHA inspectors. The
Federal Occupational Safety and Health Administration (OSHA)
regulations have been incorporated into and are enforced
through WISHA regulations. OSHA regulations would not apply
to site activities except possibly to the work of any federal
employees.
B-26
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WASHINGTON DEPARTMENT OF ECOLOGY (WDOE) FINAL CLEANUP
POLICY, JULY 10, 1984
See Chapter 2 for a discussion of the WDOE cleanup policy.
DANGEROUS WASTE REGULATIONS, CHAPTER 173-303 WAC
The Dangerous Waste Regulations were prepared under the
authority of the Hazardous Waste Disposal Act, Chap-
ter 70.105 RCW, which authorized WDOE to develop standards
for "dangerous waste" (DW) and "extremely hazardous waste"
(EHW). The general purpose of the Dangerous Waste Regula-
tions is to: (1) operate a state program for controlling DW
and EHW, (2) to provide a means of defining and designating
DW and EHW, (3) to establish a system for tracking DW and
EHW shipments, (4) to develop standards for proper treat-
ment, storage, and disposal of DW and EHW, (5) and to allow
issuance of permits to facilities that treat, store, and
dispose of DW and EHW.
For the purpose of this discussion, the wastes at Western
Processing are assumed to be EHW. The main technical re-
quirements of Chapter 173-303 WAC for such wastes that could
apply to remedial actions at the Western Processing site
are:
o Transportation Manifest, WAC 173-303-180
o Groundwater Protection, WAC 173-303-645
o Closure and Post Closure, WAC 173-303-610
o Design and Operation of Landfills, WAC 173-303-665
Transportation Manifest, WAC 173-303-180
This regulation requires that a manifest be prepared for the
transport of dangerous waste to a disposal facility. The
manifest required is the EPA Form 8700-22 as described in
the Uniform Manifest Appendix of 40 CFR part 262.
Groundwater Protection, WAC 173-303-645
This section of the dangerous waste regulations applies to
the operation of landfills. It establishes groundwater con-
centration limits for 14 contaminants and describes required
groundwater monitoring.
The owner and operator of a landfill or waste storage facil-
ity must comply with conditions specified in the facility
permit that are designed to ensure that dangerous constitu-
ents entering the groundwater from a regulated unit do not
exceed the concentration limits under WAC 173-303-180(5)
(see Table B-2).
B-27
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Table B-2
MAXIMUM CONCENTRATION OF CONSTITUENTS FOR
GROUNDWATER PROTECTION
Maximum
Concentration
(in milligrams
Constituent per liter)
Arsenic 0.05
Barium 1.0
Cadmium 0.01
Chromium 0.05
Lead 0.05
Mercury 0.002
Selenium 0.01
Silver 0.05
Endrin 0.0002
Lindane 0.004
Methoxychlor 0.1
Toxaphene 0.005
2,4-D 0.1
2,4,5-TP Silvex 0.01
Note: These are the same as the concentrations
identified in 40 CFR Part 264.94
These concentration limits cannot be exceeded in the upper-
most aquifer underlying the waste management area beyond the
point of compliance established by WDOE. WDOE will specify
in the facility permit concentration limits for dangerous
constituents in the groundwater. The owner or operator must
monitor the groundwater to determine whether regulated units
are in compliance with the groundwater protection standard.
Landfills, WAC 173-303-665
These regulations apply to owners and operators of facili-
ties that dispose dangerous wastes in landfills. The regu-
lations prohibit the disposal of EHW in landfills in Wash-
ington State other than at the Hanford Landfill (not yet
constructed). This could be interpreted as precluding the
construction of a landfill at Western Processing for the
disposal of EHW. The regulations require that a landfill
for DW be double lined and contain a lechate detection sys-
tem and include groundwater monitoring.
B-28
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Closure and Post Closure WAG 173-303-610
If wastes are allowed to remain on site in an approved land-
fill then the facility would have to be closed according to
WAG 173-303-610. The owner or operator is required to close
the facility in a manner that:
A) Minimizes the need for further maintenance;
B) Controls, minimizes, or eliminates (to the extent
necessary to prevent threats to human health and
the environment) post-closure escape of dangerous
waste, dangerous waste constituents, leachate,
contaminated rainfall, or waste decomposition
products to the ground, surface water, ground
water, or the atmosphere; and
C) Returns the land to the appearance and use of sur-
rounding land areas to the degree possible given
the nature of the previous dangerous waste
activity.
The closure standards can also be met by removing contami-
nants from the site. This removal must be done such that
the levels of dangerous waste or dangerous waste constitu-
ents or residues do not exceed background levels
[WAC 173-303-6102 (b) (i)].
REGIONAL
INDUSTRIAL WASTE DISCHARGE PERMIT AND DISCHARGE LIMITATIONS,
METRO
Metro is authorized under Chapters 90.48.165 RCW,
35.58.180 RCW, and 35.58.200 to establish standards for
pretreatment and to require approval of industrial waste
discharge permits prior to discharge of industrial waste
into the Metro sewer system. Based on this authority and
Public Laws 92-500 and 92-217 (Clean Water Act), which
require that Metro discharge achieve certain standards,
Metro has adopted Resolution No. 3374 "Regarding the control
and disposal of industrial waste into the Metropolitan
Sewerage System." Based on this resolution, all persons who
discharge industrial wastes into the sewer system must
obtain a waste discharge permit. Resolution 3374 and amend-
ments to it identify the following prohibited discharges:
3-01. Prohibited Substances
No person shall discharge any of the following prohib-
ited substances directly or indirectly into any public
sewer, private sewer, or side sewer tributary to the
Metropolitan Sewerage System:
B-29
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3-01.01 - Flammable or Explosive Materials
Any liquids, solids or gases which by reason of their
nature or quantity are, or may be, sufficient either
alone or by interaction with other substances to cause
fire or explosion or be injurious in any other way to
the POTW or to the operation of the POTW. Prohibited
materials include, but are not limited to, gasoline,
kerosene, naphtha, benzene, toluene, xylene, ethers,
alcohols, ketones, aldehydes, peroxides, chlorates,
perchlorates, bromates, carbides, hydrides and sulfides
and any other substances which the City and the State
or EPA have notified the User are a fire hazard or a
hazard to the system.
3-01.02. Substances Which Can Cause Obstruction or
Interference
Any solid or viscous substances in quantities, either
by itself or in combination with other wastes, which
are capable of obstruction of flow or of interfering
with the operation or performance of sewer works or
treatment facilities, including, but not limited to,
the following: ashes, cinders, sand, mud, straw, grass
clippings, shavings, metal, glass, tar asphalt, plas-
tics, cloth, wood, and chemical residues.
3-01.03. Odorous Substances
Any noxious or malodorous gas or substance which either
by itself or by interaction with other wastes, is capa-
ble of creating a public nuisance or hazard to life or
of preventing entry by authorized personnel to pump
stations and other sewerage facilities.
3-01.04. Toxic Vapor
Any gas or substance which either by itself or by in-
teraction with other wastes can produce a toxic vapor.
These substances include, but are not limited to, chlo-
rinated hydrocarbons, hydrogen sulfide, sulfur dioxide,
and cyanide compounds.
3-01.05. Corrosive Substances
Any gas or substance which either by itself or by
interaction with other waste may cause corrosive struc-
tural damage to sewer works or treatment facilities,
but in no case waters with a pH lower than 5.5.
3-01.06. Excessive Waste
Wastes at a flow rate and/or pollutant discharge rate
which are excessive over relatively short time periods
B-30
-------
so that there is a treatment process upset and subse-
quent loss of treatment efficiency.
3-01.07. High Temperature
Heat in amounts which will inhibit biological activity
in treatment plant facilities resulting in an interfer-
ence in the treatment process and specifically includ-
ing heat in such quantities that the temperature at the
treatment works influent exceeds 40 degrees C (104 de-
grees F) or the temperature exceeds 65 degrees C
(150 degrees F) at the point of discharge from the in-
dustrial source of public sewers and/or the Metropoli-
tan Sewerage System.
The following restricted substances can be discharged only
in the quantities shown or lesser amounts:
4-01. Restricted Substances
No person shall discharge wastes containing restricted
substances directly or indirectly into any public
sewer, private sewer, or side sewer tributary to the
Metropolitan Sewerage System, in excess of limitations
specified by conditions of the waste discharge permit
or published by the Executive Director or in excess of
limitations specified by conditions of the waste dis-
charge permit or published by the Executive Director or
in excess of other Metro, state or federal standards.
Discharge limitations established by local public
agencies which are more stringent than a National
Pretreatment Standard or Metro's limitations shown
below will apply to those industrial users within the
jurisdiction of that public agency. All other users
will comply with the following limitations expressed as
milligrams per liter.
Arsenic 1 mg/L
Cadmium* 3 mg/L
Chromium 6 mg/L
Copper 3 mg/L
Lead* 3 mg/L
Mercury 0.1 mg/L
Nickel 6 mg/L
Silver 1 mg/L
Zinc 5 mg/L
Cyanide 2 mg/L
*Metro is considering changing the standard for cadmium
to 1.2 milligrams per liter and the standard for lead
to 0.6 milligram per liter.
B-31
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An industrial discharge permit issued in June 1982 currently
authorizes a discharge from the Western Processing site of
140,000 gallons per day. This discharge has not been
carried out because water treatment facilities which would
provide pretreatment of the discharge have not been
installed.
REGULATION I AND REGULATION II OF THE PUGET SOUND AIR
POLLUTION CONTROL AGENCY
The Puget Sound Air Pollution Control Agency (PSAPCA) as
authorized by the Washington Clean Air Act, RCW 70.94, regu-
lates the emission of air contaminants in King, Snohomish,
and Pierce Counties except for emissions caused by vehicles,
pulp and paper industries, and aluminum smelters. WDOE is
authorized to regulate these sources.
PSAPCA requires all non-exempt air contaminant sources to be
registered with the agency under Regulation I, Section 5.03.
New emissions sources are approved and registered with the
agency through submission of a notice of construction and
application for approval. All sources registered with the
agency are subject to annual or periodic reports discussing
their emissions.
Components of the alternative remedial actions that may be
considered new sources include air stripping storage piles,
air stripping equipment, and other stationary equipment that
emits contaminants. For those sources requiring prior
approval by PSAPCA, the application for approval must
include a description of air emissions control equipment. A
source test demonstrating the effectiveness of emission
control devices in attaining PSAPCA air emissions standards
may be required.
PSAPCA has adopted ambient air quality standards for sus-
pended particulates, lead, carbon monoxide, ozone, nitrogen
dioxide, and sulfur dioxide. Emissions standards are
established for sulfur dioxide and particulates. Other
emissions fall under the general provision of Regulation I,
Section 9.11 which states:
It shall be unlawful for any person to cause or
allow the emission of any air contaminant in suf-
ficient quantities and of characteristics and
duration as is, or is likely to be, injurious to
human health, plant or animal life, or property or
which unreasonably interferes with enjoyment of
life and property-
New sources which do not require approval prior to construc-
tion are regulated under the general provision stated above.
All potential sources are required to employ the best
B-32
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available control technology in order to comply with PSAPCA
emissions standards. Compliance with these standards is
monitored through spot surveillance of potential sources and
by investigation of complaints regarding emissions.
LOCAL
CITY OF KENT ORDINANCES, REGULATIONS, AND PERMIT APPROVALS
Engineering Department
The following permits and regulations of the Kent Engineer-
ing Department could apply to remedial actions at the West-
ern Processing site:
o Grade and fill permit
o Temporary erosion control requirements
o Stormwater ordinance No. 2130
o Side sewer permit
o Street use and street cut permit
The grade and fill permit application requires a description
of site work including a calculation of the volume of mate-
rial moved and drawings showing current and proposed eleva-
tions. The standards used in evaluating the grade and fill
permit are those stated in Chapter 70 of the Uniform Build-
ing Code.
A temporary drainage and erosion control plan must be sub-
mitted with the grade and fill permit. The City of Kent
requires that the plan satisfy the requirements of the King
County Storm Drainage Control Requirements and Guidelines.
These requirements describe methods for erosion control and
control of offsite transport of silt. Since these guide-
lines are not designed to regulate the release of contami-
nated silt or surface water, the regulations are generally
less restrictive than the measures that the remedial actions
are expected to include.
Storm drainage ordinance No. 2130 requires submittal of a
storm drainage plan with any grade and fill permit. The
Stormwater ordinance requires that storm drainage plans for
new development include retention and/or detention facili-
ties that will maintain surface water discharge rates at or
below the preconstruction design storm peak discharge. A
variance from this requirement can be granted if it can be
shown that there is sufficient capacity in downstream facili-
ties to handle additional Stormwater runoff.
Connection to the City sewer line requires approval of a
sewer use permit. Approval of this permit is based primar-
ily on the City's calculation of the capacity of the sewer
to handle an additional discharge. A temporary sewer use
B-33
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permit was granted in winter 1984-1985 for the initial
removal actions which limited the discharge to 140,000 gpd.
This was based on the capacity of the City system and the
Metro interceptor.
A street use and street cut permit was also granted for ac-
tivities during initial removal. The purpose of this permit
is to provide a fund for street repair following potentially
damaging construction activity. Permit approval requires
posting a bond to cover these estimated costs.
Planning and Building Departments
The following permits and regulations of the Kent Planning
and Building Departments could apply to remedial actions at
the site:
o Special use permit
o Water Quality and Hazard Area Development (Chap-
ter 15.08.270 Kent City Zoning Code)
o Building permits
Construction of a solid waste landfill or a water treatment
plant would require a special use permit since neither of
these uses is allowed outright in the manufacturing zone
which is the zoning designation of the site. The approval
process for granting a special use permit includes a public
hearing with the decision to grant or deny the permit being
made by the hearing examiner and city council. The hearing
examiner uses the following criteria to make a decision to
grant or deny a special use permit:
o The proposed use will not be detrimental to other
uses legally existing or permitted in the zoning
district.
o Adequate buffering devices such as fencing, land-
scaping, or topographic characteristics protect
adjacent properties from adverse effects of the
proposed use.
o The size of the site is adequate for the proposed
use.
Under the Water Quality and Hazardous Area Development Ordi-
nance, impervious surfaces (buildings, parking lots, etc.)
are required to be at least 50 feet away from the ordinary
high water mark of a major creek which has been relocated
(Mill Creek is considered a major creek). The City requires
that all such relocation actions are done in accordance with
the recommendations of the Washington State Departments of
B-34
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Fisheries and Game as prescribed during approval of a
hydraulics permit (see discussion of state regulations in
this appendix).
Construction permits that would be required to construct a
landfill or groundwater treatment facility are a building
permit, plumbing permit, and mechanical permit. An elec-
trical permit is also required by the City but is reviewed
by the state.
B-35
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Appendix C: Detected Indicator Compounds
in Soils and Groundwater
-------
EPA-07
06) 22.0
09) 9.2
EPA-10
03) 22.
06) 39.
09) 25.
12) 52.
15) 27.
WP-MB-02
O0.)12.6
05.J5.1
15.J6.5
EPA-20
03) 58.0
06) 8.4
09) 13.0
12) 4.9
EPA-21
03) 226.
06) 63.
09) 38.
WPO-SS-008A
00) 90.
WPO-SS-008B
00)82.
EPA-19
03) 8.8
06) 8.2
EPA-03
06) 44.0
09) 5.7
WP-SB-01
09.)5.2
14.)66.2
EPA-05
06) 49.0
09) 7.3
12)98.0
WP-SB-06
04.)4.5
EPA-01
06) 8.2
09) 23.0
12 5.4
WP-SB-04
04.) 16.8
09.)7.7
INTERURBAN TRAIL
WP-MB-03
O0.)11.4
05.J24.3
10.)194.6
15.)60.0
20.)11.4
EPA-06
06) 5.2
09) 6.0
12)28
EPA-12
09) 5.1
12) 22.0
15) 8.4
I V VACANT HOUSES
EPA-02
12) 13.0
15)13.0
EPA-BERM-1
00) 13.0
WP-SB-17
O0.)5.5
EPA-BERM-8
00) 14.0
EPA-09
06) 7.0
09) 4.1
EPA-BERM-2
00) 8.6
WP-SB-14
00.13.6
EPA-BERM-9
00) 22.0
EPA-BERM-3
00) 17.0
EPA-SS-02
00) 50.0
EPA-14
03) 15.0
06) 4.8
09) 7.1
12) 9.5
15) 9.6
WP-IB-01
OOJ4.2
O9.)4.0
O4.)1.8
EPA-15
03) 8.3
06) 170.0
09) 200.0
EPA-16
03) 20.
06) 20.
09) 6.9
12) 5.5
EPA-BERM-4
00) 49.0
WP-MB-01
05.)8.4
10.)5.9
15.)29.9
INDUSTRIAL PARK
EPA-SS-06
00) 6.1
WP-SB-02
09.) 3.9
14.) 13.9
EPA-17
03) 8.3
06) 18.0
09) 13.6
12) 8.0
15) 12.8
18) 11.5
21) 11.1
24) 3.4
EPA-SS-04
00) 30.0
EPA-18
03) 3.5
06) 3.1
09) 4.3
EPA-BERM-5
00) 30.0
EPA-22
03) 79.0
06) 134.0
09) 402.0
12) 93.0
15) 10.6
WESTERN PROCESSING
OLD SANITARY
DISCHARGE LINE
EPA-SS-07
00) 6.8
WP-SB-09
OO.J4.5
19.12.9
EPA-BERM-6
00) 5.7
Legend
Data are organized at shown below:
Sample ID
EPA-23
03) 8.9
06) 16.0
09) 7.6
EPA-SS-05
00) 420.
Depth Beneath
Ground Surtace
EPA-BERM-7
00) 71.
Abbreviations.
•Indicates compound detected
but concentration not quantilied
ex 30-
EPA-SS-10
00) 4.3
EPA-SS-12
00) 10.1
SCALE: 1" = 200 FT.
Note: Off-property sediment samples are not included
(S) indicate., value presented is a sum.
FIGURE C-1
DETECTED CONCENTRATIONS^
CADMIUM IN SOILS (Atg/kg)
-------
EPA-12
06) 300
09) 220
12)48
15)79
EPA-10
03) 660
06) 42
09) 148
12) 850
15) 270
EPA-17
03) 150
06) 250
09) 140
12) 150
15) 220
18) 450
21) 370
24) 58
30)37
WP-SB-19
O0.)180
WPO-SS-10
00) 218
WP-SB-04
04.)2944
09.)227
INTERURBAN TRAIL
WPO-SS-08A
00)549
EPA-03
06) 370
09)93
WPO-SS-08B
00) 547
\ VACANT HOUSES J V* j
EPA-06
06) 130
09) 580
12)69
EPA-BERM-1
00)54
EPA-07
06)64
09) 150
EPA-08
06) 1170
09) 192
WP-SB-01
O9.)2203
WP-SB-14
00.1111
EPA-BERM-2
00) 102
EPA-BERM-9
00) 5300
EPA-BERM-3
00) 110
EPA-SS-02
00) 1100
EPA-15
03) 110
06) 7600
09) 6500
EPA-14
03) 190
06) 210
09) 130
12) 200
15)360
EPA-16
06) 600
09) 240
12) 200
15) 620
EPA-BERM-4
00) 250
INDUSTRIAL PARK
WP-MB-01
O5.)6025
10J1399
15.)1521
25.)36
EPA-SS-06
00) 210
EPA-SS-03
00) 78
EPA-SS-04
00)68
EPA-18
03) 320
06) 980
09) 140
EPA-BERM-5
00)98
EPA-20
03)97
06) 150
WESTERN PROCESSING
EPA-SS-08
00) 60
OLD SANITARY
DISCHARGE LINE
EPA-SS-05
00) 190
EPA-SS-07
00) 46
EPA-BERM-6
00)36
WP-SB-09
O0.)397
14.)36
EPA-23
03) 230
06) 510
09) 550
WP-SB-08
09.) 42
EPA-BERM-7
00) 160
EPA-SS-12
00) 450
SCALE: 1" = 200 FT.
WP-SB-12
O0.)47
EPA-21
03) 370
06) 570
09) 340
12)54
WB-MB-03
O0.)538
O5.)531
10.J7339
15.J2039
20.)95
EPA-05
03)38
06) 400
09)70
12) 1300
EPA-11
03) 140
06) 340
08) 220
10) 36
12.) 100
WP-MB-02
O0.)1210
O5.)1607
10.J1450
15.J837
25.)63
EPA-22
03) 1150
06) 2400
09) 3900
12) 560
Legend:
Data are organized ds shown below:
Sample ID
WP-MB-03
00) 11.4^ Concentration
Depth Beneath
Ground Surface
Abbreviations:
•Indicates compound detected
but concentration not quantified
ex 30*
Note:
EPA-SS-10
00)55
EPA-SS-11
00) 39
Off-property sediment samples are not included
(SI indicates value presented is a sum.
FIGURE C-2
DETECTED CONCENTRATIONS OF
CHROMIUM IN SOILS (mg/kg)
-------
EPA-01
06.) 130
09.) 150
EPA-08
06.) 170
09.) 87
WP-SB-14
O0.)88
EPA-11
06.) 105
08.) 80
10.) 460
12.) 79
WP-MB-02
00.) 559
05.) 170
EPA-21
03.) 500
06.) 450
09.) 388
EPA-03
03J210
06.) 380
O9.)148
EPA-05
03.) 140
06.) 600
09.) 250
12.) 570
EPA-02
03.) 210
12.) 83
15.) 79
INTERURBAN TRAIL
WP-SB-04
05.) 436
09.) 125
WP-MB-03
00.) 332
05.) 389
I VACANT HOUSES
SOUTH 196TH
\ f
EPA-12
03.)77
09.) 124
EPA-BERM-1
00.) 190
EPA-06
06.) 100
09.) 108
12.) 78
WP-SB-16
00.) 1,325
EPA-BERM-8
00.) 590
EPA-10
03.) 210
06.) 220
09.) 280
12) 1240
EPA-07
06)350
09)160
EPA-BERM-2
00.) 210
EPA-BERM-9
00.) 890
EPA-BERM-3
00.) 140
EPA-14
03.) 137
12.) 110
15.) 130
EPA-SS-02
00.) 320
EPA-15
03.) 3,700
06.) 5,100
09.) 5.700
EPA-16
O3.)150
O6.)260
EPA-BERM-4
00.) 180
EPA-SS-06
00.) 340
WP-MB-01
05.) 514
INDUSTRIAL PARK
EPA-17
06.) 112
18.) 77
EPA-18
06.) 325
09.) 221
EPA-20
03.)87
06.)85
EPA-SS-04
00.) 84
EPA-BERM-5
00.) 570
EPA-SS-05
00.) 580
WESTERN PROCESSING
Legend:
Data are organized as shown below:
Sample ID
WP-SB-09
00.) 80
OLD SANITARY
DISCHARGE LINE
EPA-22
03.) 103
06.) 149
09.) 335
12.) 122
EPA-SS-07
00.) 240
WP-MB-03
00.) 11.4
A
EPA-SS-09
00.) 86
EPA-SS-08
00.) 220
EPA-BERM-6
00.) 105
EPA-SS-12
00.) 560
EPA-SS-10
00.) 880
EPA-BERM-7
00.) 250
SCALE: 1" = 200 FT.
Concentration
Depth Beneath
Ground Surface
Abbreviations
•Indicates compound detected
but concentration not quantified
ex 3.0*
EPA-SS-11
00.) 200
Note: Off-property sediment samples are not included
(S) indicates value presented is a sum.
FIGURE C-3
DETECTED CONCENTRATIONS OF
COPPER IN SOILS (mg/kg)
-------
EPA-16
03.) 84,000
06.) 141,000
09.) 850
12.) 5^00
15.) 232
EPA-17
03.) 200
06.) 190
09.) 87
18.) 167
21.) 82
EPA-20
03.) 1,900
06.) 240
09.) 67
12.) 190
EPA-22
03.) 16,000
06.) 12JDOO
09.) 24000
12.) 5,600
WP-SB-10
O0.)73
WPO-SS-008A
00.) 4,000
WPO-SS-008B
00.) 3,700
WP-SB-04
05.1413
INTERURBAN TRAIL
WPO-SS-006
00.) 120
WP-MB-03
O0.)1215
05.1193
EPA-03
03.) 78.
06.) 110
09. 110
VACANT HOUSES
EPA-BERM-1
00.) 220
EPA-BERM-8
00.) 230
WP-SB-17
OOJ290
EPA-BERM-2
00.) 470
EPA-BERM-9
00.) 170
WP-SB-14
OO.J308
EPA-SS-02
00.) 10300
WP-SB-15
OOJ128
EPA-BERM-3
00.) 3300
WP-SB-13
00.1102
EPA-15
03.) 72.
06.) 1,500
09.) 4800
EPA-14
03.) 340
06.) 76
EPA-BERM-4
00.) 1090
WP-MB-02
O0.)1,624
OO.J474
EPA-SS-06
00.) 450
WP-MB-01
05.)3.852
10.)436
INDUSTRIAL PARK
EPA-18
03.) 1,130
06.) 4,500
09.) 630
EPA-SS-3
00.) 2400
EPA-SS-4
00.) 31,000
EPA-BERM-5
00.) 3,000
WESTERN PROCESSING
WP-SB-09
00.1261
EPA-SS-05
00.) 17.000
EPA-SS-08
00.) 870
EPA-SS-07
00.) 660
EPA-SS-09
00.) 120
EPA-BERM-6
00.) 770
EPA-21
03.) 6400
06.) 1000
09.) 1,010
WP-SB-12
14.) 190
EPA-BERM-7
00.) 51
EPA-SS-10
00.) 5.900
EPA-5
03.) 91.
06.) 140
09.) 66.
12.) 101
Legend:
Dala are organized as shown below:
Sample ID
WP-MB-03
00) 11.4^ Concentration
* Depth Beneath
Ground Surface
Abbreviations
'Indicates compound detected
but concentration not quantified
ex 3.0*
Note: Off-property sediment samples are not include'!
IS) indicates value presented is a sum.
EPA-23
03.) 45,600
06.) 480
09.) 121
EPA-SS-12
00.) 1,300
EPA-SS-11
00.) 190
FIGURE C-4
DETECTED CONCENTRATIONS OF
LEAD IN SOILS (mg/kg)
-------
WP-SB-04
05.)42.
EPA-11
10) 74.
12) 43.
EPA-10
03) 41.
06) 270.
09) 148.
12) 320.
15) 140.
WP-SB-15
O0.)91.
EPA-14
03) 150.
12) 49.
15)70.
WP-MB-02
O0.)310.
05.)94.
EPA-22
03) 500.
06) 219.
09) 390.
12)87.
WPO-SS-08A
00) 184.
WPO-SS-08B
00) 156.
WP-MB-03
O0.)331.
05.)279.
10.) 795
15.) 252
20.)44.
INTERURBAN TRAIL
WP-SB-17
O0.)67.
EPA-BERM-1
00) 140.
I I VACANT HOUSES
EPA-05
06) 133.
09) 74.
12)270.
WP-SB-14
O0.)70.
EPA-BERM-9
00.) 34.
EPA-BERM-3
00) 200.
EPA-SS-02
00) 78.
EPA-15
03) 170.
06) 400.
09) 500.
EPA-16
06) 76.
09) 41.
EPA-SS-06
00) 58.
INDUSTRIAL PARK
EPA-17
06) 46.
09) 40.
EPA-BERM-5
00) 180.
EPA-SS-05
00) 57.
EPA-SS-08
00) 49.
EPA-SS-04
00) 740.0
WESTERN PftOCESSING
EPA-SS-07
00) 49.
LD SANITARY
DISCHARGE LINE
EPA-21
06) 1,900.0
EPA-BERM-6
00) 290.
EPA-SS-10
00) 64.0
SCALE: 1" = 200 FT.
EPA-BERM-7
00) 160.
EPA-SS-12
00) 74.
EPA-03
03) 72.
06) 120.
09)71.
EPA-BERM-2
00) 140.
WP-MB-01
O5.)90.
10.)62.
15.J42.
EPA-BERM-4
00) 240.
Legend
Data are organized as shown below.
-Sample ID
WP-MB-03
00) 11 4-* 'Concentration
* Depth Beneath
Ground Surface
Abbrevialions.
* Indicates compound detected
but concentration not quantified
ex 30*
Noto: Off-property sediment samples are not included
(S) indicates value presented is a sum.
FIGURE C-5
DETECTED CONCENTRATIONS OF
NICKEL IN SOILS (mg/kg)
-------
EPA-10
03) 610.
06) 2,600.
09) 1,500.
12) 3,100.
15) 1.400.
EPA-16
03) 210.
06) 130.
09) 240.
12) 234.
15) 105.
WP-MB-02
0006,882
O5.)4,059
10.)1,256
15.)1,024.
200270.
WP-IB-02
000104.
090514.
14)946.
WP-SB-09
O0.)885.
29.)268.
34.)108.
EPA-21
00) 40,500.
06) 10,900.
09) 6,500.
12) 460.
15)312.
EPA-01
03) 130.
06) 160.
09)381.
12) 150.
WPO-SS-08A
00)21,000.
WP-SB-05
O0.)229.
O4.)200.
EPA-19
03) 1,200.
06) 1,900.
09) 430.
12) 860.
WP-MB-03
O0.)925.
10.)11,607.
15.)2,430.
20.)1,575.
25.)101.
EPA-06
06) 131.
09) 176.
12)262.
EPA-05
03) 510.
06) 1,300.
09) 350.
12) 2,000.
EPA-11
06) 180.
08) 150.
10) 1.200.
12) 410.
WP-SB-19
00.) 125
WPO-SS-08B
00) 20,800.
WPO-SS-10
00) 103.
EPA-13
03) 360.
06) 96.
WP-SB-04
O4.)2,035.
09.)937.
14)138
EPA-12
03) 340.
09) 117.
12) 180.
WP-SB-06
O4.)507.
WPO-SS-07
00) 158.
EPA-02
03) 260.
06) 88.
12) 200.
15) 99.
WP-SB-17
O0.)1,150.
INTERURBKN TRAIL
EPA-09
06) 390.
09) 280.
12) 190.
EPA-03
03) 420.
06) 1,500.
09) 440.
EPA-BERM-1
00) 510.
WP-SB-16
O0.)128.
WP-SB-01
O9.)361.
14)2720.
19.1648.
WP-SB-14
O0.)506
EPA-BERM-8
00) 540.
WP-SB-15
O0.)367.
EPA-14
03) 1,700.
06) 700.
09) 440.
12) 730.
15) 1,040.
EPA-BERM-2
00) 1,700.
EPA-07
06) 330.
09)210.
EPA-BERM-9
00) 1,190.
EPA-SS-02
00) 6,200.
EPA-BERM-3
00) 2,900
WP-MB-01
O5.)6,790.
10.)1,535.
15.)1,549.
EPA-15
03) 3,800.
06) 6,800.
09) 9,100.
WPO-SS-05
00) 132.
EPA-SS-03
00) 27,600.
EPA-17
03) 1,100
06) 1,600
09) 1,900
12) 1,000
15) 1,190
18) 1,370
21) 1,030
24) 400.
27) 169.
30) 280.
EPA-BERM-4
00) 13,300.
EPA-SS-06
00) 1,400.
INDUSTRIAL PARK
EPA-SS-04
00) 6.800.
EPA-18
03) 3,300.
06) T;OOO.
09) 2700.
EPA-BERM-5
00) 7800
EPA-SS-08
00) 4,700.
EPA-20
03) 1.330
06) 1,750
09) 1,300
12)2,100
15) 360.
EPA-SS-05
00)81,000.
WESTERN PROCESSING
WP-SB-11
O0.)101.
OLD SANITARY
DISCHARGE LINE
EPA-SS-07
00) 2,000.
EPA-BERM-6
00) 1900.
WP-SB-03
0.1100.
EPA-SS-12
00) 2400.
EPA-SS-10
00) 820.
EPA-26
06) 240.
09) 1,800.
WP-SB-07
000155.
EPA-24
06) 120.00
EPA-SS-11
00) 760.
SCALE: 1" = 200 FT.
WP-IB-01
O0.)679.
04.)559.
O9.)1,918.
19.)149.
WP-SB-02
O.)106.
O9.)2300.
14.)3563.
19.) 183.
EPA-22
03) 2300.
06) 5,700.
09) 11,200.
12)2,900.
15) 350.
EPA-23
03) 2,000.
06) 1,400.
09) 520.
EPA-BERM-7
00) 16,000.
Legend
Data are organized as shown below
-Sample ID
Concentration
Depth Beneath
Ground Sutlace
Abbreviations
•Indicates compound delected
but concentration not quantified
ex 30'
EPA-25
03) 560.
06) 210.
09) 290.
Note: Off-property sediment samples are not included
IS) indicates value presented is a sum.
FIGURE C-6
DETECTED CONCENTRATIONS OF
ZINC IN SOILS (mg/kg)
-------
EPA-14
09.) 4.5
12.) 10.0*
OLD SANITARY
DISCHARGE LINE
EPA-05
12.) 34.00
EPA-11
12.) 18.20
03.) 2.5'
06.) 2.5*
08.) 10.*
EPA-BERM-3
00.) 2.60
EPA-15
06.) 174,000.0
03.) 3.1*
09.) 15000.0
EPA-17
09) 16,000.0
12.) 332.5
21.) 40.0
06.) 15000.0*
EPA-SS-04
00.) 2.5*
EPA-12
15.) 3.8
Legend.
Data are organized at shown below:
-Sample ID
WP-MB-03
00) 11.4-
-Concentration
- Depth Beneath
Ground Surface
Abbreviations:
•Indicates compound detected
but concentration not quantified
ex.30*
EPA-26
06.) 17.0
09.) 7.4*
Note: Off-property sediment samples are not included
IS) indicates value presented is a sum.
FIGURE C-7
DETECTED CONCENTRATIONS OF
1 1,1 — TRICHLOROETHANE
IN SOILS (M9/kg)
-------
WPO-BC.035
50.) 29.9*
60.) 40.1
70.) 18.1*
80.) 7.7*
INTERURBAN TRAIL
f t VACANT HOUSES JI
WP-SB-14
00.) 320.
04.) 390.
14.) 11.
19.) 5.
WP-SB-15
04.) 41.0
29B) 1.80
WP-IB-03
59.) 11. *
WP-IB-02
39.) 7.4
WP-SB-08
19.) 4.9*
24.) 18.0
29.) 59.
WESTERN PROCESSING
OLD SANITARY
DISCHARGE LINE
EPA-21
09.) 24.
29.) 59.
WP-SB-12
14.13.6'
SCALE: 1" = 200 FT.
EPA-24
09.) 28.0
12.) 34.0
15.) 2.5*
EPA-01
03.) 2.5*
EPA-02
12.) 9.2*
15.) 2.7*
EPA-03
9.) 2.5*
EPA-08
03.) 2.5*
EPA-17
12.) 2.5*
EPA-22
09.) 2.5*
EPA-25
09.) 8.1*
Legend.
Data are organized as shown below:
- Sample ID
WP-MB-03
00) 11.4-
4 '
-Concentration
- Depth Beneath
Ground Surface
Abbreviations.
'Indicates compound detected
but concentration not quantified
ex. 3.0*
Note: Off-property sediment samples are not included
(S) indicates value presented is a sum.
FIGURE C-8
DETECTED CONCENTRATIONS OF
TRANS -1,2, DICHLOROETHENE
IN SOILS (ug/fcg)
-------
EPA-09
09.) 3.4
EPA-10
12.) 2.5*
15.) 2.5*
WP-SB-14
00.) 1.4
04.) 20.0
EPA-SS-02
00.) 99.
EPA-16
03.) 3.7
WP-IB-02
09.) 29.9
14.) 219
19.) 4.4
EPA-20
03.) 509
06.) 530
09.) 1300
12.) 484
15.) 123
EPA-21
09.) 2.5
WP-SB-08
29.) 5.4*
EPA-24
09.) 77
12.) 280
15.) 2.5'
I \ VACANT HOUSES J(
EPA-11
12.) 81
06.) 2.5*
08.) 2.5*
OLD SANITARY
DISCHARGE LINE
EPA-02
12.) 88
EPA-25
09.) 2.5*
EPA-05
06.) 2.5*
09.) 2.6'
12.) 19.0
EPA-15
06.) 72,000
09.) 14,000*
EPA-14
03.) 49
06.) 48
09.) 113
12.) 274
EPA-18
03.) 2.5*
06.) 2.5*
Legend:
Data are organized *\ shown below
-Sample ID
WP-MB-03 '
00) 11 4 ^ Concentration
* Depth Beneath
Ground Surface
Abbreviations
•Indicates compound detected
but concentration not quantified
ex 30*
Note: Off-property sediment samples are not included
(S) indicates value presented is a sum.
FIGURE C-9
DETECTED CONCENTRATIONS OF
TETRACHLOROETHANE IN SOILS (Ltg/kg)
-------
EPA-0-
09 i 2.i
WP-SB-14
2,500.0
50,000.0
26.0
12.0
9.1
12.0
12.3
uC
04
14
19
EPA-16
03.) 4.6*
15.) 6.5*
WP-SB-09
14.) 37.9
29.) 58.5
34.) 13.9
WP-SB-12
14.) 16.0*
29.) 6.9*
WP-SB-04
09.) 2.5*
INTERURBAN TRAIL
EPA-01
03.) 3.4
06.) 2.5
VACANT HOUSES J I
EPA-02
15.) 80.00
EPA-BERM-1
00.) 2.5
EPA-BERM-8
00.) 21.
EPA-09
09.) 2.8
12.) 7.*
EPA-12
15.) 38.0
12.) 4.9
EPA-11
06.) 19.0 03.) 4.0
08.) 38.0 10.) 9.5
12.) 312.0
EPA-10
12.) 4.6*
15.) 2.5*
EPA-SS-02
00.) 2.5*
EPA-14
03.) 11.0*
06.) 6.9*
09.) 44.0
12.) 169.00
EPA-15
06.) 580,000.
09.) 180,000.
WP-MB-01
05.) 62*
10.) 50*
WP-MB-02
15.) 28.00
EPA-BERM-4
00.) 37.
INDUSTRIAL PARK
WP-SB-02
09.) 7.1*
14.) 34.C
WP-IB-02
09.) 88.00
14.) 206.00
EPA-20
06.) 27.
09.) 676.
12.) 544.
15.) 69.
EPA-BERM-5
00.) 3.1
WP-SB-11
09.) 7
19B) 16.0
WESTERN PROCESSING
OLD SANITARY
DISCHARGE LINE
EPA-SS-07
00.) 2.5*
WP-SB-08
14.) 8.2*
19.) 8.7*
24.) 5.7*
29.) 57.
EPA-21
09.) 116.
12.) 1520
15.) 37.
EPA-BERM-6
00.) 2.6
EPA-24
09.) 4.7*
12.) 5.5*
15.) 4.8*
EPA-SS-12
00.) 2.5*
EPA-26
03.) 124.
06.) 180.
09.) 77.
DITCH
SCALE: 1" = 200 FT.
WP-SB-20
29.) 15.6
EPA-17
06.) 558,000
09.) 350,000
12.) 25300.
15.) 4,760.
21.) 1,406.
24.) 62.
WP-MB-03
05.) 3.*
10.) 21000.0
20.) 3.6*
EPA-03
06.) 2.5*
09.) 2.5*
WP-SB-01
14.) 39.0
19.) 7.1*
EPA-05
12.) 192.0
09.) 2.5*
EPA-BERM-9
00.) 6.2
EPA-BERM-3
00.) 18.
WP-IB-01
04.) 12.2
09.) 862.0
14.) 79.8
19.) 31.6
EPA-18
03.) 15.
06.) 13.
09.) 21.
EPA-SS-04
00.) 10.*
EPA-22
03.) 2.5*
06.) 7.6*
09.) 8.2*
12.) 5.2*
15.) 2.5*
EPA-BERM-7
00.) 2.5
Legend:
Data are organized as shown below:
-Sample ID
WP-MB-03
00.) 11.4 •* Concentration
* Depth Beneath
Ground Surface
Abbreviations.
'Indicates compound detected
but concentration not quantified
ex. 3.0*
EPA-25
06.) 213.0
09.) 6.4*
Note: Off-property sediment samples are not included
(S) indicates value presented is a sum.
FIGURE C-10
DETECTED CONCENTRATIONS OF
TRICHLOROETHENE IN SOILS
-------
v,'P-iB-02
14.) 38.0
19.) 16.4
29.) 4.7
39.) 94.7
44.) 6.1
43.) 7.8
54A, 3.7
546) 6.9
WPO-BC-040
40.) 6.2*
WP-SB-14
00.) 3.60
04.) 24.0
14.) 2.20
19.) 1.80
29.) 2.20
WP-SB-20
09) 38.4
19) 289.0
2'-) ) 28 3
WPO-BC-036
30.) 23.*
OFF MAP
WP-SB-05
14)4.
19AI88
198)8.2
INTERURBAN TRAIL
l_ VACANT HOUSES JI
SOUTH 1MTH ST.
\
WP-MB-03
10.) 11,000*
EPA-11
06.) 2.5'
08.) 6.1'
10.) 10.'
12.) 83.00
EPA-10
12.) 68.0
15.) 19.0
09.) 3.7*
EPA-15
06.) 48.000
09.) 9100*
EPA-14
12.) 27.0
09.) 4.1*
WP-MB-02
05.) 74.
10.) 5.
15.) 160.
20.) 6.*
25.) 7.*
40.) 1.*
INDUSTRIAL PARK
EPA-18
03.) 2.5'
09.) 2.5*
WP-IB-03
44.) 23.*
EPA-SS-04
00.) 2.8*
WP-SB-11
09.) 200.
19A) 1070.
19B 430.
WESTERN PROCESSING
EPA-20
06.) 2.5*
12.) 6.4*
OLD SANITARY
DISCHARGE LINE
WP-SB-09
14.) 13.9
19.) 15.7
24.) 18.3
29.) 8.3
34.) 57.1
WP-SB-08
29.) 4.5
EPA-23
03.) 2.5'
06.) 10.*
09.) 25.00
WP-SB-12
14.) 13*
EPA-25
06.) 216.00
09.) 19.50
SCALE: 1" = 200 FT.
WP-SB-06
00.) 3.1
04.) 3.6
14.) 12.2
19.) 3.7
24.) 24.6
29.) 196.0
34.) 118.0
WP-SB-01
14.) 3.6*
Legend
Data are organized ds shown below:
-Sample ID
WP-MB-03
00) 11 4 •* Concentration
^ Depth Beneath
Ground Surface
Abbreviations
'Indicates compound detected
but concentration not quantified
ex 30*
Note: Off-property sediment samples are not included
IS) indicates value presented is a sum.
EPA-BERM-8
00.) 2.5*
EPA-SS-02
OOJ2.5*
WP-MB-01
5.) 80.0*
10.) 74.0*
15.) 298.
20.) 8.4*
25.) 5.0*
30.) 220.
35.) 70.
40.) 17.*
50)8.1*
60.) 18.0*
70.) 25.0*
80.) 13.0*
100) 20.0
• WP-IB-01
00.) 3.1
04.) 11.0
09.) 16.8
14.) 5.3
19.) 41.7
29.) 7.0
34.) 10.2
39A) 18.8
398) 15.7
59.) 4.8
EPA-17
03.) 39,000.
06.) 394,000.
09.) 280.000.
12.) 19,900.
15.) 3,128.
21.) 891.
24.) 90.
27.) 222.
30.) 203.
EPA-22
03.) 4.2*
06.) 11.0*
09.) 43.
12.) 26.
15.) 2.5*
EPA-26
03.) 5.0*
06.) 5.2*
WPO-BC-44-050
15.4
FIGURE C-11
DETECTED CONCENTRATIONS OF
TOLUENE IN SOILS ( ug/kg)
-------
WP-SB-14
00.) 5.
14.) 1.6
19.) 2.
29.) 6.1
WP-SB-15
29B) 2.8
EPA-24
12.) 2.5
OLD SANITARY
DISCHARGE LINE
EPA-15*
06.) 5,000
WP-1B-01
09) 7.1
EPA-14
09.) 3.8*
12.) 42.
WP-SB-02*
14) 3.5
EPA-17
09) 18
12) 505
21)65
EPA-SS-04'
00) 5.10
Legend
Data are organized as shown below.
-Sample ID
WP-MB-03
00) 11.4-
- Concentration
- Depth Beneath
Ground Surface
Abbreviations.
•Indicates compound detected
but concentration not quantified
ex. 3.0*
Note: Off-property sediment samples are not included
(SI indicates value presented is a sum.
FIGURE C-12
DETECTED CONCENTRATIONS OF
CHLOROFORM IN SOILS (ug/kg)
-------
EPA-10
12.) 4500.
15.) 7,900.
03.) 440 *
EPA-22
15.) 1,000*
EPA-21
12) 1,000.
15)2,600.
WP-SB-08
09) 6,660
L VACANT HOUSES J (
OLD SANITARY
DISCHARGE LINE
WP-SB-04
00) 2500
EPA-03
09.) 760 '
EPA-12
12.) 400 '
EPA-11
12.) 600.'
EPA-14
03.) 400"
15.) 400'
WP-MB-02
05.) 95.*
EPA-17
09.) 440.'
EPA-SS-08
00) 11,000.
EPA-SS-07
00.) 510 *
EPA-SS-11
00) 1,070.
Legend.
Data are organized as shown below:
- Sample ID
WP-MB-03
00) 11.4-* Concentialion
* Depth Beneath
Ground Surface
Abbreviations.
•Indicates compound detected
but concentration not quantified
ex 3.0*
Note: Off-property sediment samples are not included
IS) indicates value presented is a sum.
FIGURE C-13
DETECTED CONCENTRATIONS OF
2,4 — DIMETHYLPHENOL
IN SOILS
-------
EPA-SS-08
00.) 884,000
EPA-21
06.) 400
EPA-SS-11
00.) 76,000
OLD SANITARY
DISCHARGE LINE
WP-MB-03
00.) 770*
EPA-11
12.) 840'
EPA-SS-04
00.) 400*
EPA-SS-07
00.) 720*
EPA-23
03.) 400*
EPA-SS-12
00.) 4,400
Legend
Data are organized at shown below:
-Sample ID
WP-MB-03
00) 11.4 •
— Concentration
* Depth Beneath
Ground Surface
Abbreviations:
'Indicates compound delected
but concentration not quantified
ex 30*
Note: Off-property sediment samples are not included
(S) indicates value presented is a sum.
FIGURE C-14
DETECTED CONCENTRATIONS OF
BENZO (A) ANTHRACENE
IN SOILS (Atg/kg)
-------
WP-SB-12A
00) .1'
EPA-09
03) 1,510
WP-SB-17
00) 28.6
WP-SS-02
00) 500
WP-SS-03
00) 1,000
WP-SB-14
00) 4,100
WP-SB-04
00) 13,900
34) 121.5
WP-MB-03
005) 17,000
010) 1M,000(S)
015) 4,800
I l\ VACANT HOUSES J (
n
EPA-15
03) 532
06) 4,870
09) 1'8,600
OLD SANITARY
DISCHARGE LINE
EPA-25
09) 111
EPA-BERM-6
00) 137
Legend
Data are organized as shown below:
-Sample ID
WP-MB-03
00) 11.4^ Concentration
* Depth Benenth
Ground Surlace
Abbreviations.
'Indicates compound detected
but concentration not quantified
ex 3.0*
Note: Off-property sediment samples are not included
(S) indicates value presented is a sum.
FIGURE C-15
DETECTED CONCENTRATIONS OF
TOTAL RGB'S IN SOILS
-------
EPA-10
oe.) epoo
12.) 16,000
EPA-20
03.) 200
06.) 5,800
09.) 6,800
12.) 13,000
15.) 34,000
EPA-21
12.) 4,400
INTERURBAN TRAIL
VACANT HOUSES J {
SOUTH 196TH ST
' N f
EPA-09
06.) 400
09.) 60,000
EPA-17
03.) 300
12.) 300
24.) 49,000
27.) 39,000
30.) 21,000
WP-IB-02
14.) 42,243
INDUSTRIAL PARK
WP-SB-11
19.)2400B
19.) 13POOM
24.) 2600
WESTERN PROCESSING
WP-SB-09
14.) 8,387
00.) 73.
09.) 3,900
19.)29.
34.137.
OLD SANITARY
DISCHARGE LINE
EPA-22
03.) 92,000
09.) 39,000
15.) 400
WP-SB-08
09.) 2/00
29.) 1,200
SCALE: 1" = 200 FT.
WP-SP-04
29.) 39,000
EPA-02
06.) 950
09.) 3,600
12.) MOO
WP-MB-03
10.) spoo
EPA-05
09.) 1£00
12.) 12,000
WP-SB-01
14.) 1.100M
EPA-12
12.) 1,400
EPA-08
06.) 230
EPA-11
03.) 14,000
12.) 20,000
WP-1B-01
19.) 280
WP-MB-02
15.) 1,400
WP-MB-01
10.) 180
WP-SB-02
09.) 2,700
EPA-SS-03
00.) 400
EPA-SS-04
00.) 1,600
EPA-23
03.) 700
Legend
Data are organized as shown below:
- Sample ID
WP-MB-03
00) 11.4-
-Concentration
- Depth Beneath
Ground Surface
Abbreviations.
'Indicates compound detected
but concentration not quantified
ex. 3.0*
Note: Off-property sediment samples are not include
(S) indicates value presented is a sum.
FIGURE C-16
DETECTED CONCENTRATIONS OF
OXAZOLIDONE IN SOILS ()Ug/kg)
-------
EPA-28-S
10.) 5,600
EPA-28-S
10.) 53.7 •
WPO-GW-035
65.) 4.1
EPA-27-S
10.) 320
EPA-27-S
10.) 918
WPO-GW-036
84.) 2
WPO-GW-040
30.) 2.3
WPO-GW-38
45.) 1.2
(OFF MAP)
WPO-GW-33-D
601.) 5.6
WPO-GW-37
85.) 3.9
(OFF MAP)
EPA-03-S
10.) 94
EPA-29-S
10.) 1.6
EPA-29-S
10.) 76
WPO-GW-32-D
101.) 9.5
EPA-12-S
09.) 210
EPA-11-S
10.5) 4,800
EPA-11-D
27.5) 3,100
EPA-14-S
13.) 12,000
EPA-22-D
25.) 77
EPA-22-S
3.5) 18
Legend
Data are organized as shown below:
- Sample ID
WP-MB-03
00.) 11 4-
-Concentration
-Depth Beneath
Ground Surface
Abbreviations.
'Indicates compound detected
but concentration not quantified
ex 3.0*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-17
DETECTED CONCENTRATIONS OF
CADMIUM IN GROUNDWATER
-------
WPO-GW- 41
85.) 12
EPA-12-S
09.) 57
WPO-GW-34-D
129.) 15
WPO-GW-34-D
129.) 32
WPO-GW-34-S
57.) 52
WPO-GW-36
84.) 27
EPA-30-S
9.5) 16
(OFF MAP)
WPO-GW-38
45.) 10
(OFF MAP)
WPO-GW-037
85.) 10
(OFF MAP)
EPA-19-S
04.) 98
04.) 15
WPO-GW-32-D
101.) 13
WPO-GW-32-S
23.) 30
EPA-13-S
04.) 545
WPO-GW-031-D
135.) 14
WPO-GW-31 -S
50.) 59
INTERURBAN TRAIL
VACANT HOUSES
^ SOUTH 196THST. , j_ / /
EPA-01-S
10.5) 70
EPA-03-S
10.) 2,200
WPO-GW-39
30.) 35
EPA-29-S
10.) 15
EPA-08-S
14.5) 26
EPA-06-S
10.) 40
EPA-05-S
10.) 400
EPA-07-S
10.) 260
EPA-10-S
13.) 17,000
EPA-11-S
10.5) 1,400
EPA-28-S
10.) 39.9*
EPA-28-S
10.) 6,100
EPA-11-D
27.5) 770
EPA-14-S
13.) 65,000
EPA-16-S
13.) 600
EPA-15-S
14.5) 170
WPO-GW-035
65.) 26
INDUSTRIAL PARK
EPA-27-S
10.) 224
EPA-17-S
13.5) 32,000
EPA-17-D
28.5) 680
WESTERN PROCESSING
OLD SANITARY
DISCHARGE LINE
WP-MB-03
00)11.4
EPA-22-S
13.5) 78
EPA-22-D
25.) 22
EPA-23-S
13.5) 400
EPA-21-S
13.) 160
WPO-GW- 44
25.) 15
Legend
Data are organized as shown below:
Sample ID
Concentration
Depth Beneath
Ground Surface
Abbreviations:
indicates compound detected
but concentration not quantified
ex.30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
WPO-GW- 33-D
601.) 11
WPO-GW-33-S
60.) 22
FIGURE C-18
DETECTED CONCENTRATIONS OF
CHROMIUM IN GROUNDWATER (jjg/L)
-------
EPA-34-S
57.) 102
EPA-34-D
129.) 103
WPO-GW-34-D
129.) 62
WPO-GW-34-S
57.) 166
EPA-06-S
10.) 51
EPA-04-S
13.) 50
WPO-GW-31-D
135.) 67
WPO-GW-31-S
50.) 171
EPA-17-D
28.5) 240
EPA-17-S
13.5) 7,200
WPO-GW-33-D
60.) 83
EPA-03-S
10.) 3,800
EPA-29-S
10.) 55
WPO-GW-32-S
23.) 75
EPA-05-S
10.) 13,000
EPA-11-D
27.5) 3,600
EPA-11-S
10.5) 4,200
EPA-18-S
14.5) 50
Legend:
Data are organized as shown below:
- Sample ID
WP-MB-03
000 11.4"
-Concentration
-Depth Beneath
Ground Surface
Abbreviations:
•Indicates compound detected
but concentration not quantified
ex.30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-19
DETECTED CONCENTRATIONS OF
COPPER IN GROUNDWATER (ng/L)
-------
EPA-28-S
10.) 294
10.) 6.5
WPO-GW-35
65.) 15
65.) 164
WPO-GW-34-D
129.) 70
WPO-GW-34-S
57.) 51
WPO-GW-36
84.) 70
WPO-GW-38
45.) 9
(OFF MAP)>
EPA-17-S
13.5) 1£00
EPA-17-D
28.5) 210
WPO-GW-34-D
129.) 5.7
129.) 10
WPO-GW-044
25.) 10
EPA-30-S
09.5) 84
09.5) 21
'(OFF MAP)
WPO-GW-31-D
135.) 61
WPO-GW-31-S
50.) 198
WPO-GW-32-S
23.) 63
WPO-GW-32-D
101.) 32
WPO-GW- 37
85.) 8
(OFF MAP)
Legend:
Data are organized at shown below:
- Sample ID
WP-MB-03
00) 11.4-* Concentration
* Depth Beneath
Ground Surface
Abbreviations
'Indicates compound detected
but concentration not quantified
ex. 3.0*
WPO-GW-33-S
33.) 52
WPO-GW-3-D
601.) 18
60.) 47
Note: Data are provided for wells sampled mon
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-20
DETECTED CONCENTRATIONS OF
LEAD IN GROUNDWATER (»ig/L)
-------
EPA-04-S
13.) 160
EPA-16-S
13.) 2,500
EPA-27-S
10.) 4,500
10.) 6400
EPA-22-D
25.) 280
EPA-19-S
04.) 629
04.) 860
WPO-GW-31-S
50.) 58
WPO-GW-31-D
135.) 68
EPA-30-S
09.5) 210
09.5) 134
(OFF MAP)
EPA-12-S
09.) 620
Legend:
Data are organized as shown below:
- Sample ID
WP-MB-03
00.) 11.4-^ Concentration
* Depth Beneath
Ground Surface
Abbreviations:
•Indicates compound detected
but concentration not quantified
ex. 30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
EPA-25-D
14.5) 40
FIGURE C-21
DETECTED CONCENTRATIONS OF
NICKEL IN GROUNDWATER (fjg/L)
-------
WPO-GW-41
85.) 69
WPO-GW-38
45.) 77
(OFF MAP)
WPO-GW-42
60.) 124
(OFF MAP)
EPA-01-S
10.5) 1,000
EPA-01-D
28.5) 48
WPO-GW-34-S
57.) 177
57.) 136
WPO-GW-34-D
129.) 91
129.) 122
129.) 206
WPO-GW-44
25.) 177
EPA-30-S
9.5) 32
9.5) 187
(OFF MAP)
EPA-26-S
14.) 34JOOO
WPO-GW- 37
85.) 39
(OFF MAP)
WPO-GW-31-S
50.) 241
WPO-GW-31-D
135.) 50
135.) 212
EPA-03-S
10.) 5£00
WPO-GW-32-S
23.) 115
WPO-GW-32-D
101.) 548
101.) 79
WPO-GW-36
84.) 70
WPO-GW-43
25.) 166
WPO-GW-40
30.) 85
INTERURBAN TRAIL
EPA-19-S
04.110QOOO
04.) 78.2*
VACANT HOUSES
I SOUTH 196TH ST , , / J
EPA-02-S
10.) 110
WPO-GW-39
30.) 381
EPA-29-S
10.) 350,000
18.) 426*
EPA-04-S
13.) 38
EPA-06-S
10.) 190
EPA-08-S
14.5) 2,800
EPA-05-S
10.) 650
EPA-09-S
13.) 1500
EPA-12-S
09.) 8400
EPA-10-S
13.) 400,000
EPA-07-S
10.) 700
EPA-11-S
10.5) 350.000
EPA-28-S
10.) 510,000
10.) 298 *
EPA-15-S
14.5) 260
EPA-11-D
27.5) 375,000
EPA-16-S
13.) 64,000
EPA-14-S
13.) 380000
WPO-GW-35
65.) 97
65.) 2,260
INDUSTRIAL PARK
EPA-27-S
10.) 94,000
10.) 58.3'
EPA-18-S
14.5) 510,000
EPA-17-S
28.5) 360,000
EPA-17-D
28.5) 160,000
WP-MB-03
00)11.4
A
WESTERN PROCESSING
EPA-20-S
13.) 11,000
OLD SANITARY
DISCHARGE LINE
EPA-22-S
13.5) 2,000
EPA-22-D
25.) 30,000
EPA-23-S
13.5) 240
EPA-21-S
13.) 390
EPA-25-S
14.5) 23
WPO-GW-33.5
33.) 48
EPA-25-D
14.5) 160
WPO-GW-33-D
60.) 155
601.) 86
Legend.
Data are organized as shown below:
Sample ID
Concentration
Depth Beneath
Ground Surtace
Abbreviations:
'Indicates compound detected
but concentration not quantified
ex.30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-22
DETECTED CONCENTRATIONS OF
ZINC IN GROUNDWATER (/ug/L)
-------
EPA-09-S
13.) 5,500
EPA-10-S
13.) 5.*
EPA-14-S
13.) 750
EPA-27-S
10.) 5200
10.) 20,000
OLD SANITARY
DISCHARGE LINE
EPA-29-S
10.) 5 '
EPA-06-S
10.) 170
EPA-11-S
10.5) 73,000
EPA-11-D
27.5) 5 200
Legend.
Data are organized at shown below.
- Sample ID
WP-MB-03
00) 11 4 -
4
-Concentration
-Depth Beneath
Ground Surface
Abbreviations
"Indicates compound detected
but concentration not quantified
ex 30*
Note. Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-23
DETECTED CONCENTRATIONS OF
1,1, 1, — TRICHLOROETHANE IN
GROUNDWATER (jtig/L)
-------
WPO-GW-35
65.) 901
65.) 260
WPO-GW-34-S
57.) 3,080
*
WPO-GW-34-D
129.) 86
129.) 30
ISOUTH196THST., . VACANT HOUSES ,
OLD SANITARY
DISCHARGE LINE
EPA-23-S
13.5) 85
EPA-25-S
14.5) 72
EPA-06-S
10.) 21 *
EPA-12-S
09.) 72
Legend:
Data are organized as shown below:
- Sample ID
WP-MB-03
00.) 11.4-
-Concentration
- Depth Beneath
Ground Surface
Abbreviations:
indicates compound detected
but concentration not quantified
ex. 3.0*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-24
DETECTED CONCENTRATIONS OF
TRANS — 1,2, DICHLOROETHENE IN
GROUNDWATER (jjg/L)
-------
WPO-GW-042
60.) 5 *
WPO-GW-39
30.) 5 *
EPA-08-S
14.5) 6.5*
EPA-28-S
10.) 90
10.) 50
EPA-16-S
13.) 7.7*
OLD SANITARY
DISCHARGE LINE
WPO-GW-33-D
60.) 5 '
WPO-GW-44
25.) 6 '
WPO-GW-32-S
23.) 50
WPO-GW-32-D
101)5*
EPA-05-S
10.) 37
Legend:
Data are organized as shown below:
-Sample ID
WP-MB-03
00.) 11.4«* Concentration
* Depth Beneath
Ground Surtace
Abbreviations:
•Indicates compound detected
but concentration not quantified
ex.30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-25
DETECTED CONCENTRATIONS OF
TETRACHLOROETHENEIN
GROUNDWATER (/ug/L)
-------
EPA-12-S
09.) 480
EPA-09-S
13.) 17,000
EPA-28-S
10.) 840
EPA-28-S
10.) 700
EPA-27-S
10.) 8,800
10.) 140,000
EPA-01-S
10.5) 3,900
EPA-01-D
28.5) 46
WP-GW-03
68.) 140
WPO-GW-32-S
23.) 2,000
EPA-11-S
10.5) 80,000
EPA-02-S
10.) 3,600
INTERURBAN TRAIL
EPA-29-S
10.) 170
EPA-29-S
10.) 120
y^SOUTH 196TH ST. , , VACAMT HOUSES / i
\ f
D
EPA-04-S
13.) 1300
EPA-5-S
10.) 16,000
EPA-7-S
10.) 1500
EPA-10-S
13.) 910
EPA-11-D
27.5) 14 000
EPA-15-S
14.5)210,000
EPA-14-S
13.) 3,400
WP-GW-02
45.) 10 *
EPA-16-S
13.) 990
WP-GW-01
85.) 10 '
EPA-18-S
14.5) 900
WPO-GW-34-S
57.) 70
EPA-17-S
13.5) 42,000
EPA-17-D
28.5) 830
EPA-20-S
13.) 1,100
Legend:
Data are organized as shown below:
Sample ID
EPA-22-D
20.) 17,000
OLD SANITARY 1
DISCHARGE LINE '
WP-MB-03
00) 11.4
A
EPA-21-S
13.) 17qOOO
EPA-26-S
14.) 1,300
EPA-25-S
14.5) 8.5'
Concentration
Depth Beneath
Ground Surface
Abbreviations:
'Indicates compound detected
but concentration not quantified
ex 3.0*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-26
DETECTED CONCENTRATIONS OF
TRICHLOROETHENE IN GROUNDWATER (jug/L)
-------
WPO-GW-'42
60.) 5 *
(OFF MAP)
EPA-11-S
10.5) 2,800
EPA-11-D
27.5) 1,100
EPA-28-S
10.) 180
EPA-28-S
10.) 110
WPO-GW-35
65.) 5 '
65.) 5 *
WPO-GW-34-D
129.) 5 *
129.) 5*
WPO-GW-34-S
57.) 5 *
WPO-GW- 44
25.) 5 *
EPA-05-S
10.) 4,100
Legend:
Data are organized as shown below:
- Sample ID
WP-MB-03 '
00) 11 4-* Concentration
* Depth Beneath
Ground Surlace
Abbreviations.
'Indicates compound detected
but concentration not quantified
ex 30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-27
DETECTED CONCENTRATIONS OF
TOLUENE IN GROUNDWATER
-------
WPO-GW-42
60.) 5 •
(OFF MAP)
EPA-04-S
13.) 17 *
EPA-14-S
13.) 1,700
EPA-27-S
10.) 1,700
EPA-27-S
10.) 6/00
VACANT HOUSES
SOUTH 196THST./I
WPO-GW-44
25.) 5 *
EPA-29-S
10.) 29
WPO-GW- 32-D
101.) 5*
EPA-08-S
14.5) 56
EPA-17-S
13.5) 12,000
EPA-17-D
28.5) 130
Legend:
Data are organized at shown below:
• Sample ID
WP-MB-03 '
00.) 11.4.
-Concentration
- Depth Beneath
Ground Surface
Abbreviations:
•Indicates compound detected
but concentration not quantified
ex. 3.0*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-28
DETECTED CONCENTRATIONS OF
CHLOROFORM IN GROUNDWATER
-------
EPA-04-S
13.) 1,000 *
EPA-12-S
O9.)1,100
EPA-08-S
14.5) 98
EPA-27-S
10.) 190
EPA-21-S
13.) 1,000
VACANT HOUSES
ISOUTH 196TH ST , i /
EPA-5-S
10.) 520
EPA-11-S
10.5) 200
EPA-11-D
27.5) 45 *
Legend:
Data are organized at shown below:
-Sample ID
WP-MB-03
00.) 11.4^ Concentration
* Depth Beneath
Ground Surface
Abbreviations:
'Indicates compound detected
but concentration not quantified
ex 30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-29
DETECTED CONCENTRATIONS OF
2,4 — DIMETHYLPHENOL IN
GROUNDWATER (*ig/L)
-------
EPA-4-S
13.) 22
EPA-09-S
13.) 20
EPA-10-S
13.) 140
EPA-14-S
13.) 20
EPA-27-S
10.) 9,100
EPA-20-S
13.) 10,000
EPA-22-D
25.) 350
EPA-24-S
13.5) 800
EPA-25-D
14.5) 110
EPA-02-S
10.) 83
EPA-07-S
10.5)620
EPA-08-D
14.5) 275
Legend:
Data are organized as shown below:
-Sample ID
WP-MB-03
00) 11.4«
A L
-Concentration
- Depth Beneath
Ground Surface
Abbreviations:
* Indicates compound detected
but concentration not quantitied
ex. 30*
Note: Data are provided for wells sampled more
than once. Well point samples taken in
Mill Creek are not included.
FIGURE C-30
DETECTED CONCENTRATIONS OF
OXAZOLIDONE IN GROUNDWATER (/ug/L)
-------
Appendix D: Environmental Migration and
Fate of Indicator Chemicals
-------
Appendix D
ENVIRONMENTAL MIGRATION AND
FATE OF INDICATOR CHEMICALS
This appendix contains migration and fate profiles that out-
line the general environmental behavior of the 17 indicator
parameters discussed in Chapters 2 and 3. Given the nature
of the contamination at Western Processing, their behavior
in soils, groundwater, and aquatic systems is emphasized.
The behavior of each chemical is discussed in terms of its
mobility, or rate of movement relative to that of water, and
its persistence, or the length of time the chemical may
exist in the environment. Mobility is important because it
determines the rate of chemical migration away from a site.
Persistence is important because it determines if a chemical
will remain in the environment long enough to reach a
receptor.
Potential interactions between chemicals are given only
minor consideration in constructing the migration and fate
profiles. The effect of organic complexation and competing
ions on metal mobility is discussed briefly. Other poten-
tial interactions (e.g., co-solvent effects and transforma-
tion byproduct formation) are not considered. The impact of
these interactions on chemical mobility and persistence at
Western Processing is uncertain. However, it should be recog-
nized that important interactions may occur.
Table D-l lists some of the key physical-chemical properties
of each organic indicator chemical. The properties of oxa-
zolidone are not included due to a lack of literature data.
The properties of the metal indicators are not included be-
cause they are not as relevant in determining their environ-
mental behavior. In addition, properties like solubility
can vary significantly depending upon a number of factors,
including pH, metal concentration, oxidation-reduction po-
tential, soil type, and the presence of competing and com-
plexing ions. With the exception of the data for PCB's,
Callahan et al. (1979) were the source of the information in
Table D-l. Mackay et al. (1983) were consulted to obtain
the physical properties for PCB's. The properties in
Table D-l do not reflect any potential interactions between
chemicals.
Tables D-2 and D-3 provide summaries of the environmental
behavior of the indicator organic compounds and metals, re-
spectively. Summaries are provided for three key sectors of
the environment: subsurface soils and groundwater, surface
soils, and aquatic systems. Potential transformation and
transfer mechanisms are listed for each indicator chemical.
Transformation mechanisms act to change the form of a chemi-
cal, while transfer mechanisms partition the chemical between
media (e.g., volatilization is a water-air transfer; sorption
D-l
-------
Table D-l
PHYSICAL-CHEMICAL PROPERTIES OF INDICATOR ORGANICS
Volatile Organics
1,1,1-trichloroethane
Trans-1,2-dichloroethene
Tetrachloroethene
Trichloroethene
Toluene
Chloroform
Acid Compounds
2,4-dimethylphenol
Base/Neutral Compounds
Benzo(a)anthracene
Other Organics
Molecular
Weight
133.41
96.94
165.83
131.39
92.13
119.38
122.16
288.28
189-499 558-729
Boiling
Point
(°C)a
74.1
47.5
121.0
87.0
110.6
61.7
210.93
Vapor Pressure
(torr)D
97.0"
200.0:j
s?:^
28.7°
150.5d
0.0621U
5 x 10
1.7xlO"2-3xlO~7
Solubility
(mg/L)
480-4,400^
600Q
150-200
1,100,
535*
8,200r
4,200
0.014-0.009
7.2-2 x 10
-4
Log Row
2.17
1.48
2.88
2.29
2.69
1.97
2.50
5.61
4.66-9.60
Boiling point at 760 torr.
torr = 1 mm of mercury (Hg).
cKow octanol-water partition coefficient.
dVapor pressure/solubility at 20°C.
eVapor pressure at 14°C.
fVapor pressure/solubility at 25°C.
gRanges from Mackay et al. (1983).
is a water-soil transfer). The persistence of a chemical in
a given sector of the environment is generally controlled by
transformation mechanisms and volatilization. Chemical mo-
bility in a given sector is mainly controlled by sorption.
Both tables list if the mechanism has a significant (S),
insignificant (I), or moderate (M) impact on behavior. In
cases where the significance is uncertain or dependent on
environmental conditions, the mechanism is denoted as pos-
sible (P) .
Generic environmental behavior profiles are provided below
for each indicator chemical. This appendix concludes with a
brief discussion of how these chemicals are likely to behave
at the Western Processing site.
D-2
-------
Table D-2
SUMMARY OF ENVIRONMENTAL BEHAVIOR OF INDICATOR ORGANIC COMPOUNDS IN
SUBSURFACE SOILS, GROUNDWATER, SURFACE SOILS AND AQUATIC SYSTEMS
Subsurface Soils and Ground»ater
Surface Soils
Compound Oxidation
l,l,l,Trichloroethane I
Trans-l,2-Dlchloro-
ethene P
Tetrachloroethene 8.8 BOS.
Trichloroethene 10.7 BOS.
Toluene I
Chloroform I
2 ,4-Dioethylphenol I
Benzo (a) anthracene I
Polychlorinated
Biphenyls I
Oxazolidone
Trans f o mat ion
Hydrolysis Blodegradatlon
a
6 BOS. P
I p"
I p"
I Pa
I
1-3,500 yrs. P1
I P
I P
I Days-Mos.b'"
P
Transfer
Sorptlon
I
I
I
I
I
I
M
S
S
-
Ox idat ion
I
P
P
P
P
I
P
P
I
-
Transformation
Hydrolysis Photolysis
P I
I I
I I
I I
I P
P I
I P
I P
I Pe
-
Transfer
Blodegradation
I
I
I
I
Pb
P"
P
P
Days-Mos. *
P
Volatilization
S
S
S
S
S
S
I
I
Mos.-Yrs.
-
Sorptlon
I
I
I
I
I
I
M
S
S
-
"Under anaerobic conditions.
D
Under aerobic conditions.
Clear, well aerated systems.
Haters high In Iron and copper.
Depends on degree of chlorinatlon.
Notes: S = Significant
I = Insignificant
H = Moderate
P = Possible
-------
Table D-2
(continued)
Aquatic Systems
Transformation
Compound Oxidation Hydrolysis
l,l,l,Trlchloroethane t 6 mos.
Trans-1 ,2-Dichloro-
ethene P I
Tetrachloroethene 8.8 mos. I
Trichloroetbene 10.7 nos. I
Toluene P I
Chloroforn I l-3f500 yrs.
2,4-Dl»ethylphenol pd I
Bento(a) anthracene 38 brs. I
Polychlorlnated
Biphenyls I I
Oxazolidone
Photolysis Blodegradation
I P"
I P"
I P"
I P"
P PL
I P
PC P
10-50 hrs P
Pe Days-Mos."'6
P
Transfer
Volatilization Sorption
Min.-Hrs. I
Min.-Hrs. I
Min.-Hrs. I
Mln.-Days I
Hrs 1
Min.-Hrs. I
I M
90 hrs. S
Mos. -Yrs. S
-
Dnder anaerobic conditions.
under aerobic conditions.
Clearr veil aerated systems.
Haters high In iron and copper.
Depends on degree of chlorination.
Notes: S = Significant
I « Insignificant
M = Moderate
P = Possible
-------
Table D-3
SUMMARY OF ENVIRONMENTAL BEHAVIOR OF INDICATOR METALS IN
SUBSURFACE SOILS, GROUNDWATER, SURFACE SOILS, AND AQUATIC SYSTEMS
Subsurface Soils and Groundirater
Surface Soils
Aquatic Syste
Compound
Arsenic
Cadmlu*
Chromium
Copper
Nickel
Lead
Zinc
Transformation
Oxidation-
Reduction Blotransformation
S P
I I
S I
S I
I I
I P
I I
Transfer
Sorption
S
S
S
S
S
S
S
Transformation
Oxidation-
Reduction Blotransformation
S P
I I
S I
I I
I I
I P
I I
Transfer Transformation
Volatll- Oxldation-
Ization Sorption Reduction Biotransformatlon
P S S P
I S I I
I S S I
I S I I
I S I I
P 5 I P
I S I I
Transfer
Volatil-
ization Sorption
P S
I S
I S
t S
I S
P S
I S
S - Significant
I •= Insignificant
P - Possible
-------
1,1,1-TRICHLOROETHANE
The behavior of 1,1,1-trichloroethane is largely controlled
by its high vapor pressure. 1,1,1-trichloroethane will not
persist in surface soils and aquatic systems because of its
tendency to volatilize. Callahan et al. (1979) give an
aquatic volatilization half-life on the order of several
minutes to a few hours, depending upon the degree of agita-
tion. Once in the atmosphere, 1,1,1-trichloroethane will
tend to slowly degrade via photo-oxidation, with a reported
half-life ranging from 1.1 to 8 years (Callahan et al., 1979).
Oxidation and hydrolysis of 1,1,1-trichloroethane in soils
and aquatic systems proceed at rates that are slow relative
to volatilization. The maximum reported half-life for
hydrolysis is 6 months; the half-life for oxidation is
unknown, but is reported to be very slow (Callahan e_t al. ,
1979). Thus, these fate mechanisms are insignificant in
aquatic systems. Photodissociation in water or air is not
expected to occur (Jaffe and Orchin, 1962).
Based on its octanol-water partition coefficient, sorption
of 1,1,1-trichloroethane is expected to be limited. Dawson
et al. (1980) state that sorption of 1,1,1-trichloroethane
will be proportional to the organic content of soils and
surface area of clays. Thus, its mobility in aquatic systems
will be controlled mainly by the rate of water movement
rather than sediment movement.
The persistence of 1,1,1-trichloroethane in subsurface soils
and groundwater will be controlled by hydrolysis. Biodegra-
dation has been found to occur, but usually under anaerobic
conditions as a result of reductive dehalogenation (Bouwer
and McCarty, 1983). Thus, biodegradation will not be impor-
tant in aerated subsurface soils and groundwater. The rate
of biodegradation is difficult to estimate on a site-
specific basis.
The mobility of 1,1,-trichloroethane in subsurface soils and
groundwater will be high because it has little tendency for
sorption.
TRANS-1,2-DICHLOROETHENE
The behavior of trans-1,2-dichloroethene is largely controlled
by its high vapor pressure. Trans-1,2-dichloroethene will
not persist in surface soils and aquatic systems because of
its tendency to volatilize. Reported volatilization half-
lives in water are several minutes to a few hours, depending
on the degree of agitation (Callahan et al., 1979). Once in
the atmosphere, trans-1,2-dichloroethene is photo-oxidized
by hydroxyl radicals, resulting in the formulation of formic
acid, hydrochloric acid, carbon monoxide and formaldehyde.
D-6
-------
The half-life for this photo-oxidation reaction is on the
order of a day (Callahan et al., 1979) .
Limited data are available on the transformation rates of
trans-1,2-dichloroethene in aquatic systems. Callahan et
al. (1979) use the behavior of two analogues to infer its
behavior: tetrachloroethene and trichloroethene. Such an
approach would suggest that trans-1,2-dichloroethene will
oxidize, but at a very slow rate relative to volatilization.
Callahan et al. (1979) cite oxidation half-lives of
10.7 months and 8.8 months for trichloroethene and tetra-
chloroethene, respectively. They also state that the oxida-
tion of both analogues is accelerated in the presence of
sunlight, and that the less-chlorinated trans-1,2-dichloro-
ethene is likely to be even more susceptible than its ana-
logues. The relative contribution of hydrolysis is unclear
given the available data. One of the analogues, trichloro-
ethene, was not hydrolyzed in water (EPA, 1975). Thus,
hydrolysis is not a significant degradation mechanism.
Photodecomposition is also likely to be insignificant given
the behavior of the two analogues (Jensen and Rosenberg,
1975).
Sorption of trans-1,2-dichloroethene will be limited as
reflected by its relatively low octanol-water partition
coefficient. Thus, its mobility in aquatic systems will be
controlled mainly by water (rather than sediment) movement.
The persistence of trans-1,2-dichloroethene in subsurface
soils and groundwater will depend upon the degree of aeration,
Under anaerobic conditions, trans-1,2-dichloroethene will be
highly persistent, unless biodegradation occurs. Bouwer and
McCarty (1983) have shown that chloroaliphatic compounds can
be degraded under anaerobic conditions as a result of reduc-
tive dehalogenation. Rates of biodegradation are difficult
to estimate on a site-specific basis. Under aerobic condi-
tions, trans-1,2-dichloroethene may degrade as a result of
oxidation.
The mobility of trans-1,2-dichloroethene in surface soils
and groundwater will be high because of its limited tendency
for sorption.
TETRACHLOROETHENE
The behavior of tetrachloroethene is largely controlled by
its vapor pressure. Tetrachloroethene will not persist in
surface soils and aquatic systems because of its tendency to
volatilize. The volatilization half-life for tetrachloro-
ethene in water is on the order of several minutes to a few
hours, depending upon the degree of agitation (Callahan et
al. , 1979). In the atmosphere, tetrachloroethene has a
half-life of about 10 days (Callahan et al., 1979). Its
D-7
-------
degradation in air is a result of photo-oxidation forming
trichloroacetylchloride and some phosgene.
While tetrachloroethene will degrade via photo-oxidation in
surface soils and aquatic systems, the rate of degradation
is slow relative to its rate of volatilization. Callahan et
al. (1979) give a maximum oxidation half-life of 8.8 months.
The relative contribution of hydrolysis is unclear given the
available data. It is expected to be insignificant in sur-
face soils and aquatic systems, as is photodecomposition.
Sorption of tetrachloroethene will be limited as evidenced
by its octanol-water partition coefficient. Sorption will
largely be controlled by the organic matter content of soils
or sediments. Thus, its mobility in aquatic systems will be
controlled by water (rather than sediment) movement.
The persistence of tetrachloroethene in subsurface soils and
groundwater will be controlled by the degree of aeration.
Under anaerobic conditions, tetrachloroethene will be highly
persistent, unless biodegradation occurs. Biodegradation of
tetrachloroethene is possible under anaerobic conditions as
a result of reductive dehalogenation (Bouwer and McCarty,
1983) . It has been demonstrated that tetrachloroethene
degrades to form trichloroethene (Bouwer and McCarty, 1983).
Rates of biodegradation are difficult to estimate on a site-
specific basis. Under aerobic conditions, tetrachloroethene
may degrade as a result of oxidation.
The mobility of tetrachloroethene in subsurface soils and
groundwater will be high because of its limited tendency for
sorption.
TRICHLOROETHENE
The behavior of trichloroethene is largely controlled by its
vapor pressure. Trichloroethene will not persist in surface
soils and aquatic systems because of its tendency to volatil-
ize. Its reported volatilization half-life from water is on
the order of several minutes to a few days, depending upon
the degree of agitation (Callahan et al., 1979). Once in
the atmosphere, trichloroethene rapidly degrades via a photo-
oxidation reaction that produces dichloroacetyl-chloride and
phosgene. Callahan et al. (1979) give a 4-day half-life for
this reaction.
While trichloroethene will degrade via photo-oxidation in
surface soils and aquatic systems, the rate of degradation
is slow relative to volatilization. Callahan et al. (1979)
give a maximum oxidation half-life of 10.7 months. The rel-
ative contribution of hydrolysis is unclear given the avail-
able data. It is expected to be insignificant in surface
soils and aquatic systems, as is photodecomposition.
D-8
-------
Sorption of trichloroethene will be limited due to its low
octanol-water partition coefficient. Organic content will
tend to control the extent of sorption. When the organic
content is small compared to the clay content (less than 1
to 5), the inorganic fraction will control trichloroethene
sorption (Richter, 1981) . Its mobility in aquatic systems
will be controlled by water (rather than sediment) movement.
The persistence of trichloroethene in subsurface soils and
groundwater will be controlled by the degree of aeration.
Biodegradation can occur under anaerobic conditions as a
result of reductive dehalogenation (Bouwer and McCarty,
1983). Rates of biodegradation are difficult to estimate on
a site-specific basis. Under aerobic conditions, trichloro-
ethene may degrade as a result of oxidation.
The mobility of trichloroethene in subsurface soils and
groundwater will be high because of its limited tendency for
sorption.
TOLUENE
The behavior of toluene is controlled by its vapor pressure.
Toluene will not persist in surface soils or aquatic systems
because of its tendency to volatilize. Its estimated half-
life in water is on the order of a few hours (Callahan et
al. , 1979) . Photo-oxidation of toluene in the atmosphere is
rapid, with a half-life of about 15 hours (Callahan et al.,
1979); this value is inferred based on the relative reactiv-
ity of toluene and reported conversion rates for m-xylene
and 1,3,5-trimethylbenzene. Benzaldehyde is the major
photo-oxidation byproduct for toluene (Laity et al., 1973).
While oxidation and photodecomposition are possible in water,
the rates of degradation are probably slow relative to vola-
tilization (Callahan et al., 1979). No rate data are avail-
able for either process. Hydrolysis is not expected to
occur, according to Callahan et al. (1979). Thus, the per-
sistence of toluene in surface soils and aquatic systems is
largely controlled by volatilization.
Sorption of toluene will tend to be limited given its low
octanol-water partition coefficient. Its mobility in aquatic
systems will be controlled by water (rather than sediment)
movement.
Toluene persistence in subsurface soils and groundwater will
be high due to the insignificance of hydrolysis as a degra-
dation mechanism. In addition, oxidation appears to occur
only in the presence of sunlight. Biodegradation is possible
given appropriate acclimation of soil bacteria and aerobic
conditions (Callahan et al., 1979; Dawson et al., 1980).
D-9
-------
Rates of biodegradation are difficult to estimate on a
site-specific basis.
The mobility of toluene in subsurface soils and groundwater
will be high. Sorption is directly related to organic matter
content (Callahan et al., 1979). Given its density (0.866
g/cm ), toluene could float on water if present in the pure
form (Dawson et al., 1980).
CHLOROFORM
The behavior of chloroform or trichloromethane will be con-
trolled by its vapor pressure. Chloroform will not persist
in surface soils or aquatic systems because of its tendency
to volatilize. Callahan et al. (1979) give a volatilization
half-life in water on the order of several minutes to a few
hours depending upon the degree of agitation. In the atmo-
sphere, chloroform degrades rapidly as a result of photo-
oxidation by hydroxyl radical attack producing phosgene and
chlorine oxide. Callahan et al. (1979) give a photo-oxidation
half-life on the order of several months.
While hydrolysis of chloroform in water is possible, the
rate of degradation is slow relative to volatilization.
Callahan et al. (1979) present a minimum half-life of
15 months based on experimental work by Billing et al. (1979).
A maximum half-life of 3,500 years is also given based on an
extrapolation made by Radding et al. (1977). Dawson et al.
(1980) give a hydrolysis half-life of 18 months. Oxidation
and photodecomposition are not significant, if they occur at
all.
Sorption of chloroform will be limited given its octanol-
water partition coefficient. The extent of sorption is con-
trolled by the organic matter content and surface area of
clays (Dawson e_t a 1. , 1980). Chloroform mobility in aquatic
systems will be controlled by water (rather than sediment)
movement.
There is some uncertainty as to how persistent chloroform is
in subsurface soils and groundwater. While hydrolysis can
occur, it is difficult to estimate a rate of degradation.
Given appropriate acclimation, biodegradation of chloroform
is possible under anaerobic conditions (Bouwer and McCarty,
1983) .
The mobility of chloroform in subsurface soils and ground-
water will be high.
2 ,4-DIMETHYLPHENOL
A lack of literature data on 2,4-dimethylphenol makes it
difficult to generate a definitive environmental behavior
D-10
-------
profile. Callahan et al. (1979) developed an inferred pro-
file based on the behavior of unsubstituted phenol and
alkylbenzenes.
Their profile suggests that the persistence of 2,4-dimethyl-
phenol in surface water will be controlled by photo-oxidation.
Photodissociation of 2,4-dimethylphenol is most likely to
occur in clear, well aerated aquatic systems. Waters high
in iron and copper could also promote the oxidation of
2,4-dimethylphenol. No data were found on the rate of
photo-oxidation. 2,4-Dimethylphenol will have little
tendency to volatilize given its low vapor pressure and high
solubility. 2,4-Dimethylphenol should be resistant to
hydrolysis, and available information on the biodegradation
of 2,4-dimethylphenol is conflicting (Callahan et al. ,
1979) .
2,4-Dimethylphenol will have little affinity for sorption to
clays, assuming it behaves like an unsubstituted phenol. It
does, however, have an affinity for sediments high in organic
matter. Thus, its mobility in aquatic systems will be af-
fected by water movement and, possibly, sediment movement.
2,4-Dimethylphenol will tend to be highly persistent in sub-
surface soils and groundwater based solely on its limited
potential for hydrolysis. Highly aerated conditions and the
presence of iron and copper would be required for oxidation
to occur. While Tabak et al. (1964) and others have shown
that 2,4-dimethylphenol can biodegrade, statements as to its
persistence on a site-specific basis are difficult to make.
2,4-Dimethylphenol will be moderately to highly mobile in
subsurface soils and groundwater, depending upon the organic
carbon content.
BENZO(A)ANTHRACENE
The mobility and persistence of benzo(a)anthracene are con-
trolled by its affinity for sorption. Its high octanol/water
partition coefficient indicates that benzo(a)anthracene will
be strongly sorbed, especially to soils and sediments high
in organic matter. As a result, the mobility of benzo(a)an-
thracene in aquatic systems is controlled by sediment movement.
Under quiescent conditions, bed sediments can become aquatic
sinks for benzo(a)anthracene. Sorption will also limit the
mobility of benzo(a)anthracene in groundwater.
Sorption also affects the persistence of benzo(a)anthracene
by limiting its susceptibility to degradation by photolysis
and oxidation, and its susceptibility to volatilization.
The dissolved fraction may undergo rapid transformation in
aquatic systems. Callahan et al. (1979) report that the
dissolved fraction can transform via: 1) photolysis with a
half-life of 10 to 50 hours, and 2) oxidation with a
D-ll
-------
half-life of 38 hours. The volatilization half-life for
benzo(a)anthracene is about 90 hours. Benzo(a)anthracene
can also be biodegraded after long-term exposure of
microbes.
The persistence of benzo(a)anthracene in groundwater will
tend to be high because it is not amenable to hydrolysis.
There is some potential for biodegradation. However, on a
site-specific basis it is difficult to determine the signif-
icance of this mechanism.
POLYCHLORINATED BIPHENYLS
Polychlorinated biphenyls (PCB's) are a family of compounds
whose environmental behavior can vary widely depending upon
the degree of chlorination. In general, as the degree of
chlorination increases so does the persistence and affinity
for sorption; volatility and solubility decrease with degree
of chlorination.
The mobility of PCB's is largely controlled by their high
affinity for sorption and, to some extent, by their limited
solubility in water. PCB sorption is a function of organic
matter content and clay content, the former being the more
important (Griffin and Chian, 1980). The mobility of PCB's
in aquatic systems is controlled by sediment transport pro-
cesses. Areas of high sediment deposition can become sinks
of PCB and later sources as the PCB redissolves into the
water column. PCB mobility in subsurface soils and ground-
water is limited by sorption. However, under conditions
where PCB is present in excess of its solubility, there is
the potential for migration as a separate phase. Roberts et
al. (1982) found that the migration of PCB as a separate
phase in soil and groundwater explained why contamination at
a spill site was more widespread than would be expected given
its affinity for sorption.
Despite their relatively low vapor pressure and molecular
weight, PCB volatilization from water and soil can occur.
Adsorption dramatically reduces the rate of volatilization,
however. Pal et al. (1980) has summarized volatilization
half-lives for PCB's in water and soils. They range from
tens to hundreds of days depending upon the type of PCB mix-
ture and environmental conditions. Volatilization is an
important mechanism because of the lack of other mechanisms
that act to degrade PCB's.
The only important degradation process is biodegradation.
However, it is only significant for the mono-, di-, and tri-
chlorinated biphenyls. Biphenyls with five or more chlorines
are essentially unaffected, while tetrachlorobiphenyls are
moderately susceptible (Callahan et al., 1979). Leifer et
al. (1983) state that there is no evidence for PCB biodegra-
dation under anaerobic conditions, but that numerous aerobic
D-12
-------
microorganisms are capable of degrading PCB's. Table D-4
gives estimates for biodegradation half-lives in different
media.
Table D-4
HALF-LIVES OF PCB'S RESULTING FROM BIODEGRADATION
(Source: Leifer e_t al. , 1984)
Pentachloro
Mono- & Dichloro Trichloro Tetrachloro and Higher
Aerobic
Surface Waters
Fresh
Oceanic
Activated Sludge 1-2 days
Soil 6-10 days
Anaerobic
2-4 days 5-40 days 1 wk-2 + mos. >1 year
several months >1 year
2-3 days 3-5 days *
12-30 days >1 year
*It is not clear how long the highly chlorinated PCB's would last under
activated sludge treatment but there appears to be no significant
biodegradation during typical residence times.
More highly chlorinated PCB's in solution have been observed
to break down through photolysis. Sufficient data are not
available to estimate photolysis half-lives for environmental
conditions (Leifer et al. , 1983). PCB's are resistant to
both oxidation and hydrolysis (Callahan et al. ,
e_t a_l. , 1983) .
OXAZOLIDONE
(1979; Leifer
Few data are available for use in constructing an environ-
mental fate profile for 3- (2-hydroxypropyl) -5-methyl-2-oxa-
zolidionone (oxazolidone) . Literature on the persistence of
this compound do not exist. The compound may biodegrade in
the soil environment. The rate at which this process would
occur is unknown.
ARSENIC
In the natural environment, four oxidation states are possi-
ble for arsenic: -3, 0, +3, and +5. The +3 and +5 states
are most commonly found in aqueous solutions, with the +5
state being the most stable and dominant. The -3 state is
present in arsine (AsH ) and is stable only under highly
reduced conditions.
D-13
-------
The environmental behavior of arsenic is largely determined
by pH and the oxidation-reduction (i.e., redox) potential of
the system. Rai et al. (19841_state that under oxidizing
conditions, H^AsO^ 2Sn<^ HAsO. are the most common species,
while H,,AsO,/ HAsO. and H»AsO ~ are most common under re-
duced conditions. Biologically mediated reactions and dis-
solved organic matter also have a significant impact on
arsenic speciation.
Dissolved arsenic concentrations can be reduced by precipi-
tation/dissolution reactions. These reactions have not been
well characterized. Rai et al. (1984) state that FeAsO is
a possible solubility-controlling solid.
Dissolved arsenic concentrations can be further reduced by
sorption reactions. Rai et al. (1984) note that the iron
and aluminum hydrous oxide content of a soil or sediment
will control the extent of sorption. Organic matter content
and pH do not seem to have a significant impact. In general,
arsenic is strongly adsorbed with the As(V) species showing
a much greater affinity than As (III) species. Callahan e_t
al. (1979) conclude that arsenic adsorption will be most
significant in aerobic, acidic, fresh waters.
Arsenic mobility in aquatic systems will be controlled by
sediment movement. In subsurface soils and groundwater,
arsenic will be relatively immobile with the As(V) species
being less mobile than the As(III) species.
In areas of high biological activity, arsenic can be mobil-
ized through methylation reactions. Methylarsines can be
produced by a number of yeasts, bacteria, and fungi (Callahan
et al. , 1979). These compounds can readily volatilize from
water. Arsenic can also volatilize under highly reducing
conditions as arsine (AsH ). Arsine is rapidly oxidized,
however, upon introduction to aerobic waters or the atmos-
phere (Callahan et al., 1979).
CADMIUM
In aqueous solutions, cadmium exists only in the +2 state.
Dissolved cadmium can be in a free ionic form or an inorganic
or organic complex. Generally, the most dominant species is
Cd . As conditions become more alkaline (i.e., pH >8-9),
hydroxide and carbonate complexes become dominant. In or-
ganically polluted waters, cadmium can be readily complexed.
Most natural waters are undersaturated with respect to known
solubility controlling phases for cadmium (Callahan et al.,
1979). For alkaline soils, CdCO and, in some cases,
Cd (PO.)9 can be solubility-controlling solids (Rai et al. ,
1984) .
D-14
-------
Cadmium is adsorbed by soils and sediments containing alumi-
num, iron, and manganese oxides. In highly polluted aquatic
systems, sorption onto organic materials can be significant
(Callahan et al. , 1979). Rai et al. (1979) note that compe-
tition with other cations (e.g., copper, lead, and zinc) and
calcium and magnesium can reduce cadmium adsorption. They
further note that there is a close relationship between cad-
mium adsorption and the cation exchange capacity of a soil.
Cadmium adsorption shows a strong pH dependency with the
extent of adsorption decreasing with pH.
Cadmium mobility in aquatic systems will be controlled by
sediment movement. In subsurface soils and groundwater,
cadmium will be relatively immobile.
Cadmium is not transformed or attenuated via biological ac-
tivity. Thus, its persistence in soils, groundwater, and
aquatic systems will be high.
CHROMIUM
In aqueous systems, chromium exists in two oxidation states:
+3 and +6. Redox potential and pH both play an important
role in determining their relative presence and mobility -
Trivalent species can exist over a relatively wide range of
redox and pH conditions; hexavalent species occur only under
strongly oxidizing conditions.
Above a pH of 5, trivalent species rapidly precipitate as an
oxide or hydroxide solid. Cr,,0., is probably the solubility-
controlling solid under moderately oxidizing conditions,
while FeCr_0. may control under slightly reduced conditions
(Rai et aJLT, 1984) .
Under oxidizing conditions hexavalent chromium exists as
hydrochromate, chromate, and dichromate species. Their rel-
ative distribution varies with pH. In the pH range of natu-
ral waters, hydrochromate predominates, while chromate pre-
dominates in the alkaline range. Hexavalent chromium is a
moderately strong oxidizing agent that can react with reduc-
ing materials to form trivalent chromium.
Both trivalent and hexavalent chromium are adsorbed onto
inorganic solids, with trivalent chromium showing a stronger
affinity than hexavalent chromium. Trivalent chromium may
be strongly adsorbed by iron and manganese oxides (Rai et
al., 1984). The affinity for trivalent chromium adsorptTon
increases with pH. The presence of organic ligands can
result in the formation of complexes that will limit adsorp-
tion. Hexavalent chromium is specifically adsorbed by iron
oxides under acidic conditions; it is relatively mobile under
neutral and basic conditions (Rai et al., 1984). Hexavalent
D-15
-------
chromium adsorption may decrease in the presence of competing
ions like SO.
Chromium mobility in aquatic systems will be controlled by
sediment movement. In subsurface soils and groundwater,-
chromium will be relatively immobile.
Biotransformation is not an important mechanism for chromium.
Thus, its persistence in soil, groundwater, and aquatic sys-
tems will be high.
COPPER
Copper in aqueous solutions can exist in a +1 or +2 state.
It has a pronounced tendency to form a number of inorganic
and organic complexes. Under oxidizing^conditions, Cu or
a Cu(II) complex with OH~, CO., ~ or SO. ~ will dominate de-
pending upon the pH and_ligana concentrations; under reducing
conditions, Cu or a Cl complex will dominate.
Dissolved copper concentrations are typically controlled by
the formation of Cu(OH) . In waters containing organic
ligands, copper can form complexes that alter its solubility
and precipitation behavior.
According to Rai et al. (1979) , copper can adsorb to organic
matter and iron and manganese oxides. Its affinity for a£-
sorption is strongly-dependent upon speciation since CuOH
is preferred over Cu . Callahan et al. (1979) further note
that in organically rich waters the ultimate dissolved cop-
per concentration will be determined by competition between
organic ligands and organic sorbants and clay particles.
Thus, it is difficult to predict with certainty how copper
will behave in polluted waters. In general, its mobility in
aquatic systems will be controlled by sediment movement. In
subsurface soils and groundwater, copper will be relatively
immobile.
Biotransformation is not an important mechanism for copper.
Thus, its persistence in soil, groundwater, and aquatic sys-
tems will be high.
NICKEL
Nickel exists in aqueous solutions in the +2 valence state.
Under reduced conditions and in the presence of sulfide,
nickel forms an insoluble complex. Under oxidizing condi-
tions below a pH of 9, nickel will complex with hydroxide,
carbonate, and sulfate ligands. Nickel will also readily
complex with organic ligands. The resulting complexes are
highly soluble.
D-16
-------
Rai et al. (1984) found NiFeO? to be the most probable solu-
bility-controlling solid under oxidizing conditions; NiS
controls under reduced conditions.
Nickel can sorb on solids containing iron and manganese ox-
ides and organic material. Callahan et al. (1979) note,
however* that nickel is not extensively sorbed. Competition
with Ca and Mg and inorganic and organic complexation
can reduce nickel adsorption. Despite its relative mobility
compared to other metals, nickel mobility in aquatic systems
will be controlled by sediment transport. Nickel will be
relatively immobile in subsurface soils and groundwater.
Biotransformation is not an important mechanism for nickel.
Thus, nickel will be persistent in soil, groundwater, and
aquatic systems.
LEAD
Lead is largely present in a +2 valence state in most aqueous
solutions. The +4 state is stable only under highly oxidizing
conditions that are not environmentally significant. Lead
has a strong tendency to form hydroxide, carbonate, sulfide,
and sulfate complexes. It also has a strong tendency to
form organic complexes that can have a major effect on solu-
bility controls and sorption.
Rai et al. (1984) state that lead-phosphates are probable
solubility-controlling solids in noncalcareous soils, while
PbCO, appears to control in calcareous and alkaline soils.
Lead is strongly adsorbed to solids containing iron and
manganese oxides. According to Rai et al. (1984), it is
also retained by ion exchange; competing ions have little
effect on lead sorption at low concentrations. The affinity
of lead for adsorption increases with the degree of organic
complexation and with increasing pH. The mobility of lead
in aquatic systems will be determined by sediment movement.
Lead will be immobile in subsurface soils and groundwater.
Lead concentrations in surface soils and bed sediments can
be reduced as a result of biologically mediated reactions.
Lead methylation can produce a volatile compound (i.e., tri-
methyl lead) that either enters the atmosphere or is oxidized
in the water column. Sufficient data are not available to
determine under what exact conditions methylation will occur
or at what rate.
ZINC
Zinc has an oxidation state of +2 in aqueous systems. Zinc
can exist in its free ionic form or as an inorganic or or-
ganic complex. Under oxidizing conditions, hydroxide,
D-17
-------
carbonate, and sulfate complexes can form. The dominance of
a particular species will be determined by the pH and ligand
concentrations.
Zinc precipitation is important under reduced conditions in
the presence of sulfide. Zinc hydroxides and zinc carbonates
are the most likely solubility-controlling solids under oxi-
dizing conditions. However, relatively high zinc concentra-
tions are required for them to form.
Zinc is primarily adsorbed onto solids containing iron, alu-
minum, and manganese oxides, clay minerals, and organic
materials. Rai et al. (1984) note that while the effects of
competing ions are not well understood, it is likely that
cadmium and magnesium may reduce zinc adsorption through
competition; certain anions may act to enhance zinc adsorp-
tion. The affinity for adsorption of zinc increases with
pH. The mobility of zinc in aquatic systems will be con-
trolled by sediment movement. Zinc will be relatively
immobile in subsurface soils and groundwater.
Biotransformation is not an important mechanism for zinc.
Thus, zinc will be persistent in soil, groundwater, and
aquatic systems.
INDICATOR CHEMICAL BEHAVIOR
The site-specific behavior of the indicator chemicals can be
discussed in terms of the profiles presented earlier and
some basic site characteristics. It is convenient to group
the indicator chemicals as follows given similarities in
their behavior: volatile organics, 2,4-dimethylphenol,
benzo(a)anthracene, PCB's, and metals.
The key site characteristics are the travel time of ground-
water from the site to Mill Creek and the travel time of
water in Mill Creek as it passes near the site. Using an
average hydraulic conductivity of 2.5 feet per day, an
effective porosity of 0.25, and an average horizontal gradi-
ent of 0.03, the approximate time for groundwater near the
center of the site to travel to Mill Creek is 1.8 years.
This is only an approximation; vertical gradients will
lengthen the actual flow path and travel time for water
originating at the center of the site. Groundwater near
Mill Creek will have a shorter distance to travel, resulting
in a shorter travel time. Chemicals with degradation half-
lives in groundwater that are equal to or less than the
1.8-year travel time should experience some degradation
prior to reaching Mill Creek.
D-18
-------
Using an average flow rate of between 6 and 12 cfgj for Mill
Creek and an average cross-sectional area of 8 ft yields a
streamflow velocity of 0.75 to 1.5 ft/sec. Given that Mill
Creek intersects the contaminated portion of the site for a
distance of about 500 feet, the Mill Creek water travel time
past the site is between 5 and 11 minutes. Again, chemicals
with degradation or volatilization half-lives equal to or
less than this travel time should dissipate somewhat prior
to leaving the site.
As a group, the volatile organics will tend to migrate rap-
idly in groundwater towards Mill Creek. Along the way,
1,1,1-trichloroethane will likely experience some degrada-
tion given the magnitude of its hydrolysis rate relative to
the travel time. Because the groundwater is relatively
shallow, it is likely that aerobic conditions exist. If
this is the case, trans-1,2-dichloroethene, tetrachloroe-
thene, and trichloroethene may also experience some degrada-
tion prior to reaching Mill Creek. Neither toluene nor
chloroform should experience significant degradation.
The volatile organics that reach Mill Creek should volatil-
ize, although because the water travel time is short compared
to the volatilization half-lives of these compounds, no
detectable reductions in concentrations would be expected in
the Western Processing reach. Volatile organics should not
be found in high concentrations in Mill Creek sediments.
The volatile organics should not persist in surface soils at
the site.
2,4-Dimethylphenol in groundwater at Western Processing
should experience little attenuation through either sorption
or degradation. Its persistence in Mill Creek is difficult
to estimate. Oxidation is possible given the copper levels
in Mill Creek. Photolysis is likely to occur only to a lim-
ited extent given that Mill Creek is not a clear, well-aerated
stream. 2,4-Dimethylphenol should be relatively persistent
in onsite surface soils, assuming limited potential for
biodegradation.
Migration of benzo (a)anthracene in groundwater at Western
Processing is expected to be very slow with no significant
degradation losses. Benzo(a)anthracene that reaches Mill
Creek will be found primarily in the sediments. Under normal
and low flow conditions, benzo (a)anthracene would tend to
persist in Mill Creek, assuming limited potential for biode-
gradation. Under high flow conditions, sediment transport
could be such that benzo(a)anthracene may migrate downstream.
Benzo(a)anthracene persistence in surface soils will be
higher, unless biodegrading organisms have been sufficiently
acclimated.
D-19
-------
PCB's will tend to persist in Mill Creek sediments, surface
soils, subsurface soils, and groundwater at Western Process-
ing. The latter two media are likely to exhibit very high
persistence due to the lack of potential degradation through
volatilization, photolysis, and biodegradation. Some degra-
dation may be found in onsite surface soils, but it will be
limited. Sediment transport under high flow conditions will
determine the persistence of PCB's in Mill Creek.
As a group, the metals will tend to behave in a similar man-
ner. All of the metals will be highly persistent in ground-
water and will migrate very slowly towards Mill Creek.
Sorption and, in some cases, precipitation reactions (e.g.,
arsenic, copper and lead) may act to dramatically reduce
dissolved concentrations. Organics present in the ground-
water may complex many of the metals and reduce their ten-
dency to adsorb; competition between metals and other ions
may have the same effect.
Metals that do reach Mill Creek will tend to concentrate in
the sediments. Sorption reactions will be even stronger in
Mill Creek due to an increase in pH and oxidation potential.
Precipitation reactions could affect copper and zinc levels.
The persistence of the metals in Mill Creek will be deter-
mined by high flow events that transport sediments away from
the site.
With the exception of arsenic and lead, the metals will be
highly persistent in onsite surface soils. Some potential
exists for the biotransformation of arsenic and lead.
D-20
-------
Appendix E: Estimating Lifetime Average
Water and Soil Intake
-------
Appendix E
ESTIMATING LIFETIME AVERAGE WATER AND SOIL INTAKE
The lifetime average soil ingestion rate (LASI) in g/kg body
weight/day, and drinking water intake (LAWI) in L/kg/day
were estimated as:
LASI =
LAWI =
N
± Z
M . .
1=:
I ;
s.
-
b.
where
si
w.
b1
M
j
soil ingestion rate in year i (g/day)
drinking water intake in year i (I/day)
body weight in year i (kg)
final year of exposure (assume 70 for residential
scenario and 65 for industrial scenario)
years in a lifetime (assume 70)
starting year of exposure (assume 1 for lifetime
scenario and 25 for industrial scenario)
LASI was estimated as 0.028 g/kg/day for the residential
scenario and 0.00082 g/kg/day for the worker scenario. LAWI
was estimated as 0.035 L/kg/day for the residential scenario
and 0.016 kg/day for the worker scenario based on the data
in Table E-l. A range of soil ingestion rates from 0.1 to
5 g/day for children 2 to 6 years in age (zero for other
ages) has also been estimated (USEPA, November 1984) and was
included in the endangerment assessment (Chapter 4). With
an average body weight of 15 kg, this would lead to a life-
time soil ingestion rate ranging from 0.00048 to 0.024 g/kg/
day-
Table E-l
ESTIMATED SOIL AND WATER INGESTION BY AGE
Age
(years)
0-0.75
0.75-1.5
1.5-3.5
3.5-5
5-18
218
Body
Weight
(kg)
5
8
12
15
38
70
Ingested
Soil
(g/day)
0
1
10
I
0.1
0.1
Ingested
Drinking Water
(L/day)
1
1
1
1
1.4
2
Kimbrough, et al. (1983)
E-l
-------
Appendix F: Methods, Assumptions, and Criteria for
Contaminant Source Quantification,
Groundwater Quality Analysis,
Battelle Groundwater Flow/Transport Model
-------
Appendix F
METHODS, ASSUMPTIONS, AND CRITERIA FOR
CONTAMINANT SOURCE QUANTIFICATION,
GROUNDWATER QUALITY ANALYSIS,
BATTELLE GROUNDWATER FLOW/TRANSPORT MODEL
CONTAMINANT SOURCE QUANTIFICATION
A contaminant distribution analysis of the Western Processing
area was conducted to evaluate the effectiveness of various
excavation alternatives and to generate site average contam-
inant levels for use in the groundwater quality analysis.
The analysis estimates the mass and concentration distribu-
tions of 23 contaminants in soil and groundwater using data
from the 3013, IRI, and RI reports (USEPA, May 1983; CH2M
HILL, October 1983/April 1984 and December 1984) .
The 23 contaminants include 14 of the 16 indicator parameters
discussed in Chapter 3 (excluding oxazolidone and 2,4-
dimethylphenol) and nine other selected contaminants that
were detected 30 or more times in all of the soil samples.
The 23 contaminants are:
Phenol Pyrene
Methylene chloride Fluoranthene
Trans 1,2-dichloroethene Benzo(a)anthracene
Chloroform Bis(2-ethylhexyl)phthalate
Trichloroethene Nickel
1,1,1-Trichloroethane Cadmium
Toluene Zinc
Tetrachloroethene Chromium
Ethylbenzene Arsenic
Naphthalene Copper
Phenanthrene Lead
PCB
The contaminants were selected because their total mass rep-
resents the vast majority of site contamination. They also
were selected to represent the range of mobilities from each
major priority pollutant class (volatiles, base/neutrals,
acid extractables, and heavy metals). Oxazolidone was ex-
cluded because it is a tentatively identified compound and
not a priority pollutant. Phenol was substituted for 2,4-
dimethyphenol as being generally a more typical acid ex-
tractable compound.
METHODS AND ASSUMPTIONS
The analysis quantifies the distribution of contaminants in
the upper 30 feet of soil and groundwater. This represents
the major zone of contamination as identified in Chapter 3.
The analysis was not used to quantify the full extent of
F-l
-------
contamination because too few data exist at depth and on the
contamination fringe. Contaminant data are associated with
a depth below the land surface as it existed prior to surface
cleanup. Topographic variations across the site therefore
were not used in the analysis. The surface cleanup and grad-
ing conducted in the fall of 1984 greatly disturbed the exist-
ing surface. This analysis does not consider these changes
because surface soil analyses are not available from the
regraded site.
The analysis is based on the Thiessen polygon method. The
concentrations measured at a particular point are assigned
to polygons containing the sample location. The concentra-
tions are assumed to be uniform within each polygon. The
shape and size of individual polygons are determined by the
distribution of sample locations. In general, closely spaced
sample locations yield smaller polygons and more accurate
results.
The existing database (discussed in Chapter 3) contains val-
ues from many different depths at the various sampling loca-
tions, thus potentially requiring a different set of polygons
for each depth. To simplify the calculations, only three
sets of polygons were constructed for the soil data:
1. Surface polygons for sample locations where analy-
ses of samples collected from the surface were
available (Figure F-l)
2. Intermediate polygons for sample locations where
analyses of samples collected between one and
15 feet were available (Figure F-2)
3. Deep polygons for sample locations where analyses
of samples collected between 15 and 30 feet were
available (Figure F-3)
To further simplify calculation, the three polygon sets were
combined into one "base" polygon set. Because most soil
data were collected from one to 15 feet, the intermediate
polygons were used as the base.
The concentrations assigned to the intermediate base polygons
at the surface and deep layers were calculated as the area-
weighted average of overlapping polygons from the surface
and deep polygon sets. Because few data were collected below
15 feet, the concentrations in the 15- to 30-foot range were
assigned to the average depth of 22.5 feet. If more than
one value was available in the interval, the concentration
at 22.5 feet was assigned the arithmetic average of the
available values. The result of this process was a soil
concentration versus depth profile for each base polygon
F-2
-------
WP-SS-03
WP-SB-14
WP-SS-01
EPA-BERM-1
EPA-BERM-8
WP-SB-01
EPA-BERM-9
EPA-BERM-3
WP-IB-01
EPA-BERM-4
• WP-SB-02
EPA-SS-08
WP-SB-03
EPA-BERM-7
0 100 200
(Approximate Scale)
F-3
FIGURE F-1
SURFACE SOIL POLYGONS FOR
CONTAMINANT DISTRIBUTION
CALCULATIONS
WESTERN PROCESSING
Kent, Washington
-------
EPA-05
0 100 200
(Approximate Scale)
F-4
FIGURE F-2
INTERMEDIATE BASE
POLYGONS FOR CONTAMINANT
DISTRIBUTION CALCULATIONS
WESTERN PROCESSING
Kent, Washington
-------
WP-SB-14
WP-SB-15
0 100 200
(Approximate Scale)
FIGURE F-3
DEEP SOIL POLYGONS FOR
CONTAMINANT DISTRIBUTION
CALCULATIONS
WESTERN PROCESSING
Kent, Washington
F-5
-------
with a value assigned at zero and 22.5 feet, as described
above, and the actual values for depths between one and
15 feet.
The next step in the analysis was to generate soil concen-
trations at standard depths of zero, 3, 6, 9, 12, and 15 feet.
This was done by linear interpolation between values at the
depths where data were actually available. An average con-
centration was then calculated for each 3-foot-thick polygon
slice to 15 feet by averaging the concentration at the top
and bottom of each slice. The average concentration within
the 15- to 30-foot slice was assigned the value calculated
for 22.5 feet. The result of this step was an estimated
contaminant concentration for each soil block defined by the
base set of polygons and standard depth intervals described
above.
Two sets of polygons were constructed for groundwater: a
shallow set using monitoring wells that were screened at
depths less than 15 feet and a deep set between 15 and
30 feet (see Figures F-4 and F-5). The concentrations were
translated to the base polygons by area weighting as de-
scribed above. The result was a shallow and deep ground-
water concentration assigned to each base polygon.
Groundwater concentrations were assumed to be uniform from
the water table (at about 6 feet) to 15 feet and from 15 to
30 feet. They were assigned the values calculated in the
previous step. This assumption was necessary because detailed
(i.e., every few feet) groundwater quality versus depth data
are not available.
The final step was to calculate the total mass and average
concentration of each of the 23 contaminants in soil and
groundwater by polygon and by depth. Partial excavation of
a layer was approximated by using the ratio of removed thick-
ness to total layer thickness. These final calculations
were made assuming the following:
o Dry soil density = 1.44 g/cm
o Water density = 1.00 g/cm
o Total soil porosity = 0.30
RESULTS
The Western Processing area was divided into 10 areas for
purposes of alternative evaluation (see Figure 1-4). The
contaminant distribution analysis was conducted for Areas I
and II, Area V, and Area IX (onsite plus the east drainage
ditch, the area between the site and Mill Creek, and the
triangular area north of the site). Contaminant masses in
Area I/II are overestimated because area boundaries do not
F-6
-------
EPA-06
0 100 200
(Approximate Scale)
FIGURE F-4
SHALLOW GROUNDWATER POLYGONS FOR
CONTAMINANT DISTRIBUTION
CALCULATIONS
WESTERN PROCESSING
Kent, Washington
F-7
-------
0 100 200
(Approximate Scale)
F-8
FIGURE F-5
DEEP GROUNDWATER POLYGONS FOR
CONTAMINANT DISTRIBUTION
CALCULATIONS
WESTERN PROCESSING
Kent, Washington
-------
exactly coincide with polygon edges. The polygon area rep-
resenting Area I/II is about 15.5 acres. The actual area is
about 11.9. Concentrations are not affected because they
are calculated using the larger contaminant masses divided
by the larger soil volume times density.
The site average contaminant concentrations and total masses
in Areas I/II, V and, IX are summarized in Tables F-1A and IB.
The two tables present a range of possible results based on
the way non-detects were handled in the database. Table F-lA
summarizes the results where the concentrations of the non-
detects were set equal to the stated detection limit. These
results represent the high end of possible contaminant levels.
Table F-lB summarizes the results where the concentrations
of the non-detects were set equal to zero. These results
represent the low end of possible contaminant levels. The
actual contaminant levels are most likely between these
extremes.
Comparison of Tables F-lA and F-lB shows that the major dif-
ference in Area I/II occurs in the concentrations of the
base/neutrals (naphthalene, phenanthrene, pyrene, fluor-
anthene, benzo(a)anthracene, and bis(2-ethylhexyl) phthalate).
High detection limits were frequently associated with non-
detects in the base/neutral data base (especially in ground-
water) . The groundwater average often was skewed one to
three orders of magnitude higher than actual detected quanti-
ties when the non-detects were set equal to the detection
limit. The lower concentration values are also supported on
the basis of geochemical data that indicate the base/neu-
trals will be strongly adsorbed on soil. The actual ground-
water concentrations would be significantly lower than those
calculated with non-detects equal to detection limits if
they were in equilibrium with the measured soil concentra-
tions. All subsequent calculations used the lower values
for the base/neutrals in groundwater and soils. The values
presented in Table F-lA were used in subsequent calculations
involving the other 17 contaminants in Area I/II because
major changes did not occur. The use of these values also
yielded slightly more conservative results.
Major differences occur in the concentrations of most organic
contaminants in Areas V and IX. Like Area I/II, high detec-
tion limits were frequently associated with non-detects in
the organics data base (especially in soils). The soil
averages were often skewed one to three orders of magnitude
higher than actual detected quantities when the non-detects
were set equal to the detection limit. All subsequent cal-
culations involving Areas V or IX soils used the lower or-
ganic concentration values shown in Table F-lB.
The use of site average groundwater concentrations should be
done with caution. Because the shallow and deep polygons
F-9
-------
Table F-1A
TOTAL MASSES AND SITE AVERAGE CONTAMINANT CONCENTRATIONS
(NONDETECTS = DETECTION LEVEL) WESTERN PROCESSING, KENT, WASHINGTON
Area Contaminant
Total Mass
in Soil
0-6 ft.
(Kg)
Total Mass
in Soil
6-15 ft.
(Kg)
Total Mass
in Soil
15-30 ft.
(Kg)
Average Soil
Concentration
6-15 ft.
(yg/Kg)
Average Soil
Concentration
15-30 ft.
(yg/Kg)
Average
Groundwater
Concentration
6-15 ft.
(yg/U
Average
Groundwater
Concentration
15-30 ft.
(yg/D
I
H-»
O
I/II Volatiles
Phenol
Methylene chloride
Trans 1,2-dichloroethene
Chloroform
Trichloroethene
1,1,1-Trichloroethane
Toluene
Tetrachloroethene
Ethylbenzene
BN/AE
Naphthalene BN/AE
Phenanthrene
PCB
Pyrene
Fluoranthene
Benzo(a)anthrancene
Bis(2-ethylhexyl)
phthalate
Metals
Nickel
Cadmium
Zinc
Chromium
Arsenic
Copper
Lead
Total Mass
in Soil
0-6 ft.
(Kg)
758
364
67
74
2,292
423
1,044
205
129
8,754
22,887
59
17,496
1,487
1,751
4,571
19,426
4,739
777,160
76,329
1,381
51,046
1,358,397
Total Mass
in Soil
6-15 ft.
(Kg)
1,239
358
69
149
5,221
571
2,124
289
251
942
1,126
379
821
808
779
3,867
20,219
7,782
463,049
164,687
938
84,428
634,276
Total Mass
in Soil
15-30 ft.
(Kg)
460
62
2
3
19
2
22
2
3
348
374
8
348
348
353
453
5,147
610
93,713
16,681
1,808
10,678
5,290
5,011
1,447
215
601
21,112
2,307
8,590
1,168
1,017
3,813
4,555
1,132
3,319
3,266
3,155
15,637
81,756
31,466
1,872,331
665,907
3,795
341,383
2,564,678
1,116
149
5
6
46
5
55
4
7
845
907
20
845
845
857
1,097
12,486
1,480
227,355
40,469
4,387
25,905
12,834
Average
Groundwater
Concentration
6-15 ft.
(yg/U
109,383
56,886
20,312
2,394
29,521
21,624
1,646
125
19
2,570
2,570
0.22
2,758
2,570
2,585
2,570
15,132
2,392
126,448
5,253
20
1,357
342
Average
Groundwater
Concentration
15-30 ft.
(yg/D
1,501
48,974
158
2,015
7,245
1,017
317
5
5
29
20
0.10
20
20
40
20
14,263
964
117,687
316
18
785
266
-------
Table F-1A (cont.)
Area
Contaminant
Volatiles
Phenol
Methylene chloride
Trans 1,2-dichloroethene
Chloroform
Trichloroethylene
1,1,1-Trichloroethane
Toluene
Tetrachlorothylene
Ethylbenzene
BN/AE
Naphthalene
Phenanthrene
PCB
Pyrene
Fluoranthene
Benzo(a)anthracene
Bis(2-ethylhexyl)
phthalate
Metals
Nickel
Cadmium
Zinc
Chromium
Arsenic
Copper
Lead
Total Mass
in Soil
0-6 ft.
(Kg)
758
35
34
34
34
34
35
34
34
20
19
6
19
19
20
19
654
171
30,643
1,679
306
1,235
7,057
Total Mass
in Soil
6-15 ft.
(Kg)
1,239
60
56
56
58
56
57
57
56
42
42
1
42
42
42
40
654
47
7,747
923
324
1,172
796
Total Mass
in Soil
15-30 ft.
(Kg)
124
185
43
43
44
43
46
43
43
88
88
3
88
88
88
92
951
21
3,221
899
818
2,070
239
Average Soil
Concentration
6-15 ft.
(Ug/Kg)
2,140
985
930
930
953
931
950
945
930
696
693
24
693
693
695
667
10,840
773
128,439
15,318
5,382
19,440
13,200
Average Soil
Concentration
15-30 ft.
(yg/Kg)
1,229
1,845
429
426
431
426
462
426
426
882
882
25
882
882
882
920
9,456
203
32,041
8,946
8,135
20,591
2,376
Average
Groundwater
Concentration
6-15 ft.
(yg/L)
746,973
40,605
147,009
1,217
89,536
3,624
5
187
5
2,844
2,844
0.1
2,844
2,844
2,858
2,844
1,341
69
18,287
71
13
87
33
Average
Groundwater
Concentration
15-30 ft.
(ug/L)
57
127
5
3,789
8,312
5
48
5
5
31
20
0.1
20
20
40
20
478
119
30,876
84
21
69
25
-------
Table F-lA (cont.)
I
h-"
to
IX Volatiles
Phenol
Methylene chloride
Trans 1,2-dichloroethylene
Chloroform
Trichloroethylene
1,1,1-Trichloroethane
Toluene
Tetrachlorothylene
Ethylbenzene
BN/AE
Naphthalene
Phenanthrene
PCB
Pyrene
Fluoranthene
Benzo(a)anthracene
Bis(2-ethylhexyl)
phthalate
Metals
Nickel
Cadmium
Zinc
Chromium
Arsenic
Copper
Lead
Total Mass
in Soil
0-6 ft.
(Kg)
31
4
0.1
0.1
0.1
0.1
0.1
0.1
0.1
18
18
38
18
18
18
19
597
135
15,478
9,470
338
2,337
1,699
Total Mass
in Soil
6-15 ft.
(Kg)
42
3
0.1
0.1
0.2
0.1
0.1
0.1
0.1
26
26
1
26
26
26
26
582
82
14,221
3,767
444
1,758
480
Total Mass
in Soil
15-30 ft.
(Kg)
78
0.2
0.2
0.2
0.2
0.2
1
0.2
0.2
46
46
4
46
46
46
65
739
28
4,319
817
446
1,637
147
Average Soil
Concentration
6-15 ft.
(yg/Kg)
1,038
3
3
3
5
3
5
3
3
625
626
35
626
626
625
635
14,364
2,018
350,817
92,928
10,960
43,359
11,846
Average Soil
Concentration
15-30 ft.
(yg/Kg)
1,157
3
3
3
3
3
20
3
3
676
676
70
676
676
676
964
10,942
412
63,915
12,092
6,597
21,373
2,179
Average
Groundwater
Concentration
6-15 ft.
(yg/U
20
5
123
5
111
15
5
5
5
20
20
0.1
20
20
40
20
540
95
36,101
13
10
52
5
Average
Groundwater
Concentration
15-30 ft.
(yg/L)
20
5
18
5
46
7
5
5
5
20
20
0.1
20
20
40
20
40
1
48
10
10
50
5
-------
Table F-1B
TOTAL MASSES AND SITE AVERAGE CONTAMINANT CONCENTRATIONS
(NONDETECTS = 0) WESTERN PROCESSING, KENT, WASHINGTON
I
1-1
u>
I/II Volatiles
Phenol
Methylene chloride
Trans 1,2-dichloroethene
Chloroform
Trichloroethene
1,1,1-Trichloroethane
Toluene
Tetrachloroethene
Ethylbenzene
BN/AE
Naphthalene
Phenanthrene
PCB
Pyrene
Fluoranthene
Benzo(a)anthrancene
Bis(2-ethylhexyl)
phthalate
Metals
Nickel
Cadmium
Zinc
Chromium
Arsenic
Copper
Lead
Total Mass
in Soil
0-6 ft.
(Kg)
293
337
0.01
28
2,245
376
1,016
148
82
8,207
22,391
58
17,003
993
1,086
3,988
19,360
4,738
777,160
76,329
1,312
51,022
1,358,394
Total Mass
in Soil
6-15 ft.
(Kg)
724
358
1
99
5,220
883
2,122
271
203
369
549
279
83
135
4
3,207
20,164
7,778
494,287
164,679
855
84,395
636,033
Total Mass
in Soil
15-30 ft.
(Kg)
190
61
1
1
17
1
22
0.3
1
4
0
0
0
0
0
147
5,103
605
93,713
16,681
1,753
10,678
5,285
Average Soil
Concentration
6-15 ft.
(ug/Kg)
2,929
1,446
2
403
21,105
2,275
8,582
1,097
819
1,493
2,221
1,128
334
544
17
12,968
81,533
31,451
1,872,331
665,879
3,458
341,250
2,564,661
Average Soil
Concentration
15-30 ft.
(ug/Kg)
460
148
1
2
43
1
52
1
3
11
0
0
0
0
0
356
12,380
1,468
227,355
40,469
4,253
25,905
12,823
Average
Groundwater
Concentration
6-15 ft.
(yg/D
108,583
56,872
20,297
2,378
29,508
21,609
1,633
109
2
2
0
0
0
0
0.3
0
15,129
2,391
126,447
5,249
14
1,333
340
Average
Groundwater
Concentration
15-30 ft.
(yg/D
1,490
48,971
154
2,012
7,244
1,014
314
0
0
23
0
0
0
0
0
0
14,250
964
117,687
313
12
757
263
-------
Table F-lB (cont.)
I
h->
*»
Volatiles
Phenol
Methylene chloride
Trans 1,2-dichloroethene
Chloroform
Trichloroethylene
1,1,1-Trichloroethane
Toluene
Tetrachlorothylene
Ethylbenzene
BN/AE
Naphthalene
Phenanthrene
PCB
Pyrene
Fluoranthene
Benzo(a)anthracene
Bis(2-ethylhexyl)
phthalate
Metals
Nickel
Cadmium
Zinc
Chromium
Arsenic
Copper
Lead
Total Mass
in Soil
0-6 ft.
(Kg)
29
1
0
0
0.1
0
1
0.02
0
0
0.1
5
0.1
0.1
0
0.01
654
171
30,643
1,679
306
1,235
7,057
Total Mass
in Soil
6-15 ft.
(Kg)
75
4
0.01
0
1
0
1
1
0
0
0
0
0
0
0
0.04
654
46
7,747
924
324
1,172
796
Total Mass
in Soil
15-30 ft.
(Kg)
0
163
1
0
1
0
4
0.1
0
0
0
0
0
0
0
0
951
16
3,221
899
813
2,070
233
Average Soil
Concentration
6-15 ft.
(pg/Kg)
1,240
60
0.2
0
23
0
20
15
0
0
0.06
3
0.06
0.06
0
1
i 10,840
753
128,439
15,318
5,381
19,440
13,199
Average Soil
Concentration
15-30 ft.
(pg/Kg)
0
1,623
3
0
6
0
37
1
0
0
0
0
0
0
0
0
9,456
162
32,042
8,946
8,807
20,590
2,324
Average
Groundwater
Concentration
6-15 ft.
(yg/L)
745,954
40,603
147,005
1,213
89,535
3,620
1
183
0
0
0
0
0
0
0
0
1,327
68
18,284
66
5
42
29
Average
Groundwater
Concentration
15-30 ft.
(yg/D
39
122
0
3,787
8,310
0
44
0
0
23
0
0
0
0
0
0
461
119
30,876
80
15
24
21
-------
Table F-1B (cont.)
I
I—"
Ul
IX Volatiles
Phenol
Methylene chloride
Trans 1,2-dichloroethylene
Chloroform
Trichloroethylene
1,1,1-Trichloroethane
Toluene
Tetrachlorothylene
Ethylbenzene
BN/AE
Naphthalene
Phenanthrene
PCB
Pyrene
Fluoranthene
Benzo(a)anthracene
Bis(2-ethylhexyl)
phthalate
Metals
Nickel
Cadmium
Zinc
Chromium
Arsenic
Copper
Lead
Total Mass
in Soil
0-6 ft.
(Kg)
0
4
0
0
0.01
0
0.03
0
0.01
0.2
0.02
37
0.2
0.1
0.3
1
594
135
15,478
9,470
333
2,320
1,698
Total Mass
in Soil
6-15 ft.
(Kg)
0
3
0
0
0.1
0
0.1
0
0.01
0
0
0
0
0
0
1
547
81
14,221
3,767
435
1,738
479
Total Mass
in Soil
15-30 ft.
(Kg)
0
4
0
0
0.01
0
1
0
0
0
0
0
0
0
0
443
728
25
817
443
1,429
142
Average Soil
Concentration
6-15 ft.
(yg/Kg)
0
67
0
0
2
0
3
0
0.1
0
0
0
0
0
0
10,719
13,509
1,992
92,928
10,719
42,872
11,809
Average Soil
Concentration
15-30 ft.
(yg/Kg)
0
68
0
0
0.1
0
18
0
0
0
0
0
0
0
0
6,557
10,770
367
12,092
6,557
21,161
2,098
Average
Groundwater
Concentration
6-15 ft.
(yg/U
0
20
118
0.3
106
10
0.1
0
0
0
0
0
0
0
0
0
540
94
7
0
3
0
Average
Groundwater
Concentration
15-30 ft.
(yg/L)
0
5
18
0
46
7
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-------
are generally much larger than the base polygons (caused by
fewer groundwater data points) an extremely high contaminant
concentration at one monitoring well can disproportionately
affect a large area, particularly when the other wells have
relatively low concentrations of the same compound. An ex-
ample is trans 1,2-dichloroethene. Trans 1,2-dichloroethene
was detected in 12 of 26 onsite wells. The site average is
about 20,000 yg/L. Well 21 had a measured concentration of
390,000 yg/L. If this value is subtracted, the site average
concentration is about 1,000 yg/L. Other contaminants that
fall into this category are methylene chloride, and to a
lesser degree, 1,1,1-trichloroethane, toluene, chloroform,
and phenol.
The effectiveness of excavation in Areas I/II, V, and IX was
evaluated. The total contaminant masses remaining (by con-
taminant class) versus excavation depth are summarized in
Figures F-6, F-7, and F-8 and Table F-2A. The break in slope
at 15 feet shown in the figures followed by a straight line
decrease to 30 feet is caused by the use of the single con-
centration value at 22.5 feet to represent the 15- to 30-foot
layer. The site average contaminant concentrations remaining
versus excavation depth are summarized in Tables F-2B and
F-2C. Table F-2B shows that a 15-foot excavation of Area I/II
would remove the selected metals to background except for
zinc, which would remain at about two times background. All
metals are at background in Area V except zinc, which would
require excavation to 3 feet to reach background levels.
All metals are at background in Area IX except chromium and
zinc, which would require excavation to 9 and 12 feet, re-
spectively, to reach background levels.
Table F-2A
EXCAVATION SUMMARY—FRACTION REMAINING
IN GROUNDWATER AND SOIL BY CONTAMINANT CLASS
Excavation
Area
I/II
V
IX
Depth (ft.)
0-6
0-15
0-3
0-6
0-15
0-3
0-6
0-15
Metals
.40
.04
.48
.32
.13
.79
.49
.13
Volatiles
.82
.20
1.0
1.0
.10
.86
.76
.44
BN/AE
.17
.01
1.0
1.0
0
.45
.38
.37
F-16
-------
1.00
.75
•BASE NEUTRALS/ACID EXTRACTABLES
Z
<
IS
/VOLATILES
.50
u
tr
.25
AREA l/ll POLYGONS
EPA 1 TO 12
EPA 14 TO 18
EPA 20 TO 26
WP-SB-01 TO 03
WP-MB-01 TO 03
TOTAL SELECTED METALS
TOTAL SELECTED BASE NEUTRALS/ACID
EXTRACTABLES
TOTAL SELECTED VOLATILES
INITIAL MASSES (kg)
METALS = 4x106
B.N./A.E. =6x104
VOLS.= 3x104
10 15
EXCAVATION DEPTH (ft)
20
25
30
NOTE: SEE TEXT FOR LIST OF
23 SELECTED CONTAMINANTS
FIGURE F-6
EXCAVATION SUMMARY FOR AREA l/ll
WESTERN PROCESSING, KENT,WASHINGTON
F-17
-------
1.00
l
O o
o
oc
BASE NEUTRALS/ACID
EXTRACTABLES
AREA V POLYGONS
WP-SB-07 TO 12
WP-IB-02
TOTAL SELECTED METALS
TOTAL SELECTED BASE NEUTRALS/ACIl|
EXTRACTABLES
TOTAL SELECTED VOLATILES
INITIAL MASSES (kg)
METALS = 6 x 104
B.N./A.E. =6x103
VOLS.= 5 x 103
15 20
EXCAVATION DEPTH (ft)
NOTE: SEE TEXT FOR LIST OF
23 SELECTED CONTAMINANTS
F-18
FIGURE F-7
EXCAVATION SUMMARY FOR AREA V
WESTERN PROCESSING, KENT .WASHINGTON
-------
1.00
AREA IX POLYGONS
EPA 13
EPA 19
WP-SB-04 TO 06
WP-SB-19
A TOTAL SELECTED METALS
A TOTAL SELECTED BASE NEUTRALS/ACID
W EXTRACTABLES
• TOTAL SELECTED VOLATILES
a
5 yj
UJ Z
S. O
I °
O Z
O
O
e
BASE NEUTRALS/ACID EXTRACTABLES
INITIAL MASSES (kg)
METALS=6x104
B.N./A.E. =6x101
VOLS.= 2x101
EXCAVATION DEPTH (ft)
NOTE: SEE TEXT FOR LIST OF
23 SELECTED CONTAMINANTS
FIGURE F-8
EXCAVATION SUMMARY FOR AREA IX
WESTERN PROCESSING, KENT,WASHINGTON
F-19
-------
Table F-2B
SOIL EXCAVATION SUMMARY—
SITE AVERAGE INORGANIC CONCENTRATIONS REMAINING
Excavation
Depth
Area
I/II
IX
Background
Concentrations
(yg/kg)
From Table 3-5
Site Average Concentration Remaining in Soil
From Excavation Depth to 30 Feet (pg/kg)
(feet)
0
3
6
9
12
15
0
3
6
9
12
15
0
3
6
9
12
15
Cd
15,900
14,500
12,700
8,810
4,240
1,480
1,190
580
420
330
220
200
1,800
1,500
1,010
640
470
410
Cr
313,000
311,000
275,000
187,000
102,000
40,500
17,400
13,100
11,300
10,400
9,600
8,950
104,000
84,400
42,400
17,700
13,520
12,100
Cu
177,000
166,000
144,000
107,000
64,000
25,900
22,300
20,700
20,200
20,000
20,100
20,600
41,000
36,800
29,600
24,500
22,200
21,400
Ni
54,300
48,100
38,400
25,800
18,200
12,500
11,200
10,400
9,940
9,600
9,400
9,460
14,200
13,000
12,200
11,600
11,200
10,900
Pb
2,420,000
1,900,000
968,000
325,000
105,000
12,800
40,200
13,400
6,430
6,200
5,490
2,380
17,200
11,700
5,800
2,580
2,350
2,180
Zn
1,620,000
1,130,000
844,000
616,000
392,000
227,000
207,000
94,500
68,300
63,300
51,800
32,000
252,000
230,000
172,000
120,000
89,000
63,900
As
5,000
4,570
4,160
4,080
4,180
4,390
7,200
7,050
7,100
7,300
7,670
8,130
9,090
8,760
8,240
7,640
7,090
6,600
2,900 40,000 73,000 43,000
76,000
109,000 12,000
Note: Underscored values are first concentrations below background.
F-20
-------
Table F-2C
SOIL EXCAVATION SUMMARY—SITE AVERAGE ORGANIC CONCENTRATIONS REMAINING
Excavation
Site Average Concentration Remaining in Soil From Excavation Depth to 30 Feet (yg/kg)
Depth Methylene
Area (feet) Chloroform Ethylbenzene Chloride Phenol
I/II 0 270 465 950 3,000
15 67 150 1,100
V 0 0 0 830 520
15 00 1,600 0
IX 0 0 0 82 0
15 0 0 68 0
Excavation Site Average
Depth Benzo(a) Bis(2-ethyl-
1 Area (feet) anthracene hexyllphthalate
KJ
I/II 0 1,300 8,900
15 0 360
V 0 0 0
15 0 0
IX 0 2 180
15 0 340
Tetrachloro-
ethene
601
4
5
1
0
0
Concentration
Fluoranthene
1,400
0
1
0
1
0
Trans 1,2-
Toluene dichloroethane
3,870 170
55 5
26 2
37 3
10 0
18 0
Remaining in Soil (yg/kg)
Naphthalene PCB
10,400 400
11 0
0 25
0 0
1 270
0 0
1,1,1-Trichloro- Trichloro-
ethane ethene
1,200 9,100
5 46
0 11
0 6
0 0
0 1
Phenanthrene Pyrene
27,800 20,700
0 0
1 1
0 0
0 1
0 0
Note: Nondetects = 0 except for Area I/II volatiles where nondetects = detection limit.
-------
Table F-2C shows that with a 15-foot excavation of Area I/II,
all selected organics would be reduced to nondetected or low
levels except methylene chloride, phenol, and bis(2-ethyl-
hexyDphthalate. Methylene chloride in Area V and bis (2-
ethylhexyDphthalate in Area IX also would remain at levels
above 100 pg/kg..
GROUNDWATER QUALITY ANALYSIS
A geochemical model of the Western Processing area was pre-
pared to estimate contaminant concentration changes in sur-
face water and groundwater associated with Alternatives 1,
2, 3, and 5. The results were used to support initial treat-
ment process selection and conceptual design, to identify
contaminants that could be significantly reduced during var-
ious lengths of pumping, and to qualitatively evaluate ef-
fectiveness of remedial actions on Mill Creek water quality.
Accurate prediction of groundwater contaminant concentrations
versus time requires simulation of complex physical and geo-
chemical processes. These processes include: contaminant
partitioning between groundwater and the aquifer skeleton
and other sorption sites such as particulate organic carbon
and metal hydroxides; mixing processes such as dispersion
and diffusion; recharge dilution; chemical reactions such as
precipitation, hydrolysis, and chelation; cosolvent/common
ion effects; and biological degradation.
The geochemical model presented here required numerous as-
sumptions to make the problem tractable. Clearly most of
the assumptions are violated to some degree in natural sys-
tems; however, many are offsetting. The usefulness of the
model is its ability to estimate relative contaminant
behavior.
The geochemical model was developed in two ways: (1) using
a mass balance approach and (2) using an exponential decay
approach. Both yield exactly the same results. The mass
balance method is based on a series of recursive equations.
Mass is "removed" from the system at the first timestep.
The resulting mass then becomes the initial mass of the sec-
ond timestep and is allowed to equilibrate with groundwater.
The process is then repeated into the future. An exponential
decay function of the form C=Co exp(-at) can be written to
replace the recursive equations. The decay constant (a) for
each chemical is calculated based on the retardation factor
(velocity of water divided by the velocity of chemical).
ASSUMPTIONS
The mass balance method assumes that "equilibrated" ground-
water containing contaminants is removed from the contami-
nated soil volume or cell as a slug (i.e., no dispersion,
F-22
-------
diffusion, or recharge dilution). Groundwater free from
contaminants then is moved into the cell to fill the pore
space (one pore volume). Desorption equilibrium described
by a linear isotherm with a constant distribution
coefficient is assumed to occur between the aquifer skeleton
and the groundwater. Equilibrium is assumed fast compared
to groundwater flow and totally reversible. Cosolvent/
common ion effects and chemical and biochemical reactions
are also assumed to be insignificant. The groundwater and
aquifer skeleton equilibrium concentrations are determined
using the linear isotherm and total mass of contaminant
available in the cell (sum of contaminant adsorbed on the
aquifer skeleton and dissolved in groundwater). The equili-
brated groundwater containing contaminants then is removed
from the cell as a slug and the process repeated. Each
groundwater pore volume removes contaminants from the
system, thus changing the estimated soil and groundwater
concentrations with time in the cell.
The linear isotherm used here is:
Sc = Kd x We
where
_ mass of solute adsorbed or precipitated
~ unit dry mass of soil
mass of solute in solution
we = ~^^~^~———————^—^^-^^^^^^—^^^^^—
unit volume of water
Kd = distribution coefficient
The distribution coefficients for organic compounds were
estimated based on octanol/water partition coefficients,
where available, or on solubility (Karickhoff et al. , 1979).
The distribution coefficients for the metals were approxi-
mated based on ratios of the average shallow soil to shallow
groundwater concentrations determined from site-specific
data. The relative metal mobilities (Ni>Cd>Zn>Cu>Pb), as
represented by the distribution coefficients, agree with
those reported in the literature (e.g., Abd-Elfattah and
Wada, 1981; Huang et al., 1977; and Balistrieri and Murray,
1982).
Additional assumptions were as follows:
1) No slurry wall (Alternatives 2, 3, and 5)
2) Contaminated zone is 15 acres (11-acre site plus
4 adjacent acres) and 25 feet thick below the water
table
3) Effective porosity =0.25
F-23
-------
4) Pumping is distributed uniformly throughout the
contaminated area (Alternative 2 and less accurate
but applicable to Alternative 3)
5) Total pumping rate = 100 gpm; effective pumping
rate (i.e., removing water from or flushing only
the contaminated zone) = 70 gpm (Alternatives 2,
3, and 5)
6) No significant changes in pore volume
7) Pore volume flushing time = 0.8 year (based on
assumptions 1 through 6)
8) Site average contaminant distributions are
appropriate.
9) Insignificant contaminant contribution from the
unsaturated zone (i.e., contaminants in unsaturated
zone have either been removed or capped) (Alterna-
tives 2 and 3)
10) Soil density = 1.44 g/cm
11) Particulate organic carbon content of soil
= 1 percent
Mass Balance Equations
The derivation of the recursive equations used in the mass
balance approach was as follows:
Let
Total mass of contaminant = TMCONT
Mass of soil contaminant = MCSOIL
Mass of groundwater contaminant = MCGW
Density of soil = ps
Density of water = pw (assumed equal to one)
Volume of soil = Vs
Porosity of soil = ns
By definition:
TMCONT = MCSOIL + MCGW (1)
and
v, MCSOIL „ pw x ns x Vs
I\Q —
(2)
ps x Vs
MCSOIL
MCGW X
MCGW
ns
ps
F-24
-------
Rearranging Equation 2 yields:
MCSOIL = MCGW x Kdn* PS (3)
or
ns
MCGW = MCSOIL x
Kd x ps (4)
Substituting Equation 3 into Equation 1 yields:
TMCONT = MCGW x Kd X pS + MCGW
ns
urrw 1i a. Kd x psx
= MCGW (1+ —— ) (5)
Note: 1+ K ps is by definition the Retardation Factor (R)
Then per pore volume time (n):
MCGW(n+l) = TMCONT(n)/R (6)
MCSOIL(n+l) = TMCONT(n)-MCGW(n+1) (7)
TMCONT(n+l) = MCSOIL(n+l) (8)
Substituting Equation 4 into Equation 1 and proceeding as
above yields from the soil viewpoint:
MCSOIL(n+1) = TMCONT(N) x ((R-1)/R) (9)
MCGW(n+l) = TMCONT(n) - MCSOIL(n+l) (10)
TMCONT(n+1) = MCSOIL(n+1) (11)
Exponential Decay Equation
The relative decrease in mass (or concentration) with time
described by Equations 6 through 11 is constant, i.e., for
each pore volume the same ratio of mass is removed from the
system. With the constant ratio, the total mass removed per
pore volume decreases over time. This constant reduction
can be described by a first order exponential decay equation
of the form
Mt = Mo exp(-at) (12)
where
Mt = Contaminant mass at time t
Mo = Initial contaminant mass
a = Decay constant (first order)
t = Time
(Note: Concentrations can be substituted for mass in
Equation 12)
F-25
-------
The decay constant can be calculated as:
a = ln(Mo/Mp) (13)
where,
Mo = Initial total mass of contaminant
Mp = Total mass of contaminant remaining after I pore
volume
Using Equations 6, 7, and 8, Mo/Mp can be written as:
Mo/Mp = 1/(1-(1/R)) (14)
or using Equations 9, 10, and 11
Mo/Mp = R/(R-1) (15)
(Note: Equations 14 and 15 are equal)
Substituting Equation 15 into Equation 13 yields an expres-
sion for the decay constant in terms of the retardation
factor:
a = ln(R/(R-l)) (16)
Equation 16 can be substituted into Equation 9 and corrected
for fractional pore volume times to yield:
Mt = Mo exp(-(ln(R/(R-l)) x Time/
Pore volume time) (17)
GROUNDWATER PUMPING RESULTS
Equation 17 was used to calculate the fraction remaining and
concentrations versus time for the 23 contaminants discussed
in the Contaminant Source Quantification section of this
appendix. The results are presented in Tables F-3A, F-3B,
and F-3C. The results must be interpreted remembering the
assumptions and limitations of the analysis. They represent
relative behavior and should not be relied upon alone for
treatment process selection and conceptual design, or quan-
titative determinations of the effectiveness of groundwater
pumping as a remedial action component.
Table F-3A shows that after five years of source pumping any
contaminants with distribution coefficients less than
about 1.3 would be reduced to 50 percent of initial concen-
trations. Typically these are the low molecular weight vol-
atile organics (phenol through 1,1,1-trichloroethane on the
list of 23 selected contaminants). Thirty years of pumping
would reduce to 50 percent of initial concentrations those
F-26
-------
Table F-3A
GROUNDWATER PUMPING SUMMARY—ESTIMATED CONTAMINANT FRACTION
REMAINING IN SOILS AND GROUNDWATER VERSUS TIME
a
Compound/Element
Phenol
Methylene
chloride
Trans 1,2-
dichloroethene
Chloroform
Trichloroethene
1,1,1-Tri-
chloroethane
Toluene
Tetrachloro-
ethene
Ethylbenzene
Naphthalene
Phenanthrene
PCB
Pyrene
Fluoranthene
Benzo(a)
anthracene
Bis(2-ethylhexyl)
phthalate
Nickel
Cadmium
Zinc
Chromium
Arsenic
Copper
Lead
Fraction Remaining After Time (Years)
Kd
0.03
0.11
0.19
0.58
1.20
1.30
3.0
4.8
9.1
15
180
630
1,300
1,300
2,500
3,300,000
4
10
15
100
140
200
7,500
5
-6
8x10
-3
3x10
0.02
0.2
0.44
0.47
0.71
0.81
0.89
0.93
0.99
1
1
1
1
1
0.77
0.90
0.93
0.99
0.99
0.99
1
10
-
-5
1x10
-4
4x10
0.04
0.19
0.22
0.50
0.65
0.79
0.87
0.99
1
1
1
1
1
0.60
0.81
0.87
0.98
0.98
0.99
1
15
-
-
-g
7x10
Sxio"
0.08
0.10
0.34
0.52
0.71
0.81
0.98
0.99
1
1
1
1
0.46
0.73
0.81
0.97
0.98
0.98
1
20
-
-
-7
1x10
2xlO~
0.04
0.05
0.25
0.42
0.63
0.76
0.98
0.99
1
1
1
1
0.35
0.66
0.76
0.96
0.97
0.98
1
25
-
-
-
3xlO~4
0.02
0.02
0.18
0.34
0.56
0.70
0.97
0.99
1
1
1
1
0.27
0.59
0.70
0.95
0.96
0.97
1
30
-
-
_
7xlO~5
7xlO~
0.01
0.13
0.27
0.50
0.66
0.97
0.99
1
1
1
1
0.21
0.53
0.66
0.94
0.96
0.97
1
a
Indicator contaminants (from Chapter 3) and other selected contaminants identified in more than
30 soil samples from the site and vicinity.
Distribution coefficient.
Q
M/Mo or C/Co (mass or concentration basis).
F-27
-------
Table F-3B
GROUNDWATER PUMPING SUMMARY—
PREDICTED GROUNDWATER CONCENTRATIONS
WITH CAPPING OR 6-FOOT EXCAVATION
Di=t vi Dut i on L i-e-f f icier,t . (23
Im t la i Groundwater Concent rat ion t ug/ 1)
:HRS
1.
£.
3.
i*.
5.
10.
15.
£0.
£5.
3C1.
60.
££.
FRflCTION
REMfilNING
C/Co
. 096773330
.009365076
. 000906£30
.000087705
. 000008487
. 000000000
. 000000000
. 000000000
. 000000000
. 000000000
. 000000000
. 000000000
GW CONC
(ug/1)
4064.
393.
38.
4.
0.
0.
0.
0.
0.
0.
0.
0.
TRIChLOROETHYLENE
DistriDut ion Coefficient 1. £0
4£000. Initial Groundwater Concentration (ug/1)
YEflRS
1.
£.
3.
4.
5.
10.
15.
£0.
£5.
30.
60.
i£0.
FRflCTION
REMfllNINB
C/Co
. 648078£00
.719£36600
.603968300
.517301300
. 438712000
. 19£468£00
. 084438090
.037044000
.016£51640
.0071£9791
. 000050834
. 000000003
BW CDNC
(ug/1)
13569.
11508.
9760.
8£77.
7019.
3079.
1351.
593.
£60.
114.
1.
f,E7hYLENE CHLORIDE
D:st riOUT ion Coefficient = .11
I rat ial Groundwater Concent rat ion ( LID/ I)
1,1,1 TRICHLORQETHflNE
Distribution Coefficient = 1.30
£000. Initial Grounowater Concentration (ug/1)
*> EAn'S
2,
4.
5.
10.
15.
£0.
£5.
30.
60.
1£0.
TSC,,-^ 1
L i 5 t r i b '
I n 1 1 1 a i
YEflRS
1.
£.
2.
4.
5.
10.
15.
£0.
£5.
30.
6e.
1£0.
FRflCTION
REMAINING
C/Co
. 315048508
. 033£55530
. 031£70310
.009851661
. 003103750
. 000003633
. 000000030
. 000000000
. 000000000
. 000000000
. 000000000
. 000000000
,£ DICHLOROETHYLENE
jtion Coefficient =
BW CONC
( U D / i )
16383.
5161.
16£6.
51£.
161.
1.
0.
0.
0.
0.
0.
0.
. 19
Grounowat er Concentration (ug/1)
FRflCTION
REMOININS
C/Co
. 453147400
. £0534£600
. 033050490
.04£ 165530
.019107£30
. 000365086
.000006976
. 000000133
. 000000003
. 000000000
. 000000000
. 000000000
GW CONC
(ug/1)
3483.
1581.
716.
3£5.
147.
3.
0.
0.
0.
0.
0.
0.
YEflRS
1.
4.
5.
10.
15.
£0.
30.
60.
1£0.
FRflCTION
REWfllNING
C/Co
. 658£43000
.736581100
.63£i65700
.54£551800
.465641300
.£168,51800
. 100361E00
.047011700
.0£1830580
.010193160
. 000103901
. 000000011
BW CONC
(UO/1)
7467.
6408.
55012.
47£0.
4051.
1886.
878.
-409.
130.
89.
1.
0.
TOLUENE
Distribution Coefficient 3.00
77012. Initial Groundwater Concentration (ug/1)
YEflRS
1.
4.
5.
10.
15.
£0.
£5.
30.
60.
1£0.
FRRCTION
REMfllNINE
C/Co
.933693500
.871763500
. 813378600
.760006400
.703613000
. 503550600
. 3573£6100
.£53563300
.179931800
. 1£768£000
. 01630£680
. 000££5778
BW CONC
(ug/1)
766.
715.
667.
6£3.
58i.
413.
£93.
£08.
148.
105.
13.
0.
CHLOROFORM
Distribution Coefficient .58
Initial Groundwater Concentration (ug/1) =
YEflRS
1.
4.
10.
£0.
30.
FrtfiCTION
REMAINING
C/Co
.7£6637700
.5£800£300
. 3836.664^0
.£78786500
. ££
. 041037330
. 0083i3£07
.00:634063
. i?0i?^*T, 1 5£
. 00006311? =
. 0000'?00lZ'5
.000000000
BW CONC
(ug/1)
1533.
613.
446.
90.
TETRflCHLOROETHYLENE
Distribution Coefficient = 4.80
Initial Groundwater Concentration (ug/1)
YEflRS
1.
30.
60.
1£0.
FRflCTIOlM
REMfllNING
C/Co
. 957595800
.916983700
. 878105500
.840370100
. 805£13700
.648369100
. 5££075800
. 4£038£600
.336497600
.£7£563100
.074£90640
.005519039
GW CONC
(ug/1)
46.
4£.
44.
4£.
40.
£6.
17.
14.
4.
0.
F-28
-------
Table F-3B (Continued)
ETHY^BENZENE
Initial Groundwater Concentration (ug/1)
YEARS
1.
£.
3. .
4.
5.
10.
15.
20.
25.
30.
60.
120.
NflPTHflLENE
Initial Ground
YEflRS
1.
2.
3.
4.
5.
10.
15.
20.
25.
30.
60.
120.
FRflCTION
REKnlMNG
C/Co
977216700
954952400
933195500
91 1934200
891157300
794161300
707722700
630692200
562046000
500871400
250872100
062936830
GW CONC
( U D / I )
10.
10.
9.
9.
9.
8.
7.
6.
6.
5.
3.
1.
water Concentration (ug/1)
FRflCTION
REMfllNING
C/Co
986064400
972323000
958773100
945412000
932237100
869066100
810175700
755275800
704096100
6563B4600
430840700
185623700
GW CONC
fiNTHRflCENE
0. Initial
YEflRS
1.
£.
3.
4.
5.
10.
15.
20.
25.
30.
60.
120.
BIS12-E
FRflCTION
REMHINING
C/Co
. 999915200
.999830500
. 933745800
.999661000
. 9935763^0
.99915260^
.936729500
. 338306401?
.997863400
. 997460700
. 994927800
.989881300
THY^HEXYL) PTt-iflLflTE
Distribution Coefficient
0. Initial
YEflRS
I .
2.
2.
4.
5.
10.
15.
20.
c'5.
30.
60.
i2C.
Groundwater Concen
FROCTION
REMfllNING
C/Co
1 . 000000000
1. 000000000
1 . 000000000
1 . 000000000
1 . 000000000
1. 000000000
1 . 000000000
1 . 00000001?!?
1. 000000il?^l
1. 001?00I?1?00
1. 000000000
1. 00000000?
GW CONC
(ug/1 )
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
£.'500. 00
GW CONC
-------
Table F-3B (Continued)
NICr.El-
Distr .
>£-•;=
i;
3.
+ ,
5.
112.
if.
£0.
£5.
30.
j >.
i ^^ .
L1 i E T r i
YE-3E
1 .
=..
3.
4.
5.
1 0.
15.
££•.
£5.
22.
60.
i£3.
£!stn
V E H ^' b
1.
£,
3.
H .
-, £
15.
£i?.
25.
30.
60.
120.
CHRO*;
Distri
D'-'tion Coefficient
FRflCTlON
K£V^:N;NG
C/Co
. 9*1561000
. 856037300
. 81£8l£300
.771763300
. 5356£8800
. 459668t00
. 354773700
.£73803600
. 21 1313400
. 044653350
.001993922
D'.it ion Coefficient
FRfiCTION
C/Co
. 979228300
. 958888100
. 938370300
. 919466300
. 90036740^1
. 81 0661 b^0
.729893300
.65-172100
. 591696400
. 53274"*200
. 283316300
. 080551720
Dution Coefficient =
FRfiCTION
REMfilNING
C/Co
. 966064400
. 972323000
.958773100
. 945412000
. 9^2237-00
. 869066100
.6.0175700
. 755275800
.704036100
. 65636-*600
. 4306-0700
. 185623700
^
but ion Coef f 1C lent =
Initial Groundwater Concent rat
YEfiRS
1 _
£p
3.
4.
5.
10.
15.
20.
25.
30.
60.
120.
FRftCTION
REC.fi INING
C/Co
. 397886800
. 995778100
. 993673800
.99157330^
.989478500
. 979067800
. 968766600
. 958573800
. 948488200
.938508700
. 880798600
775806200
GW CONC
I UD / 1 )
13523!
12841.
i£192.
11577.
8334.
6895.
5322.
4107.
3170.
670.
30.
10. 00
Gw CONC
( u g / i )
1469.
1438.
1408.
1379.
1351.
1216.
1095.
586.
888.
799.
426.
121.
15. 00
GW CONC
-------
Table F-3C
GROUNDWATER PUMPING SUMMARY—
PREDICTED GROUNDWATER CONCENTRATIONS
WITH 15-FOOT EXCAVATION
E- i E - r i D '-i t ic.
n Cc.-i_Gr:IDc.
Di =-r i;:. ,'t lor. Coefficient .11
I r. 11 i a l Grc.uriCwa ' er Concent rat ic,r. t..iD/i> =
. 007451,665
.001456255
71.
14.
0.
0.
0.
C.
.000000000
.00OOOOC"0
s- CG..IC:
( U D / 1 )
.003715033
= - r1 out ion Coefficient
itial G~ouna*at e-- Cor.ce
C/Co
Gw
(i.lC/1)
1£73.
8- i.
0.
;00. Initial
YEfiRS
1.
£._
3.
4.
5.
10.
15.
£0.
25.
30.
60.
120.
Gr-ouncwater Concentrati.
FRACTION
REKfllNING
C/Co
. 792178700
.627547100
. 497123500
.393815300
. 31 1972100
.097326610
. 030363190
. 009472469
.002955147
.0009219E3
. 000000850
. 000000000
GW CONC
(ug/1)
5704.
4513.
3579.
2835.
2246.
70i.
£19.
68.
£1.
7.
0.
0.
1.1.1 TRICHLORQEThfl'ME
Dl St r 1 b
500. I r. ; t lai
YEARS
i.
2.
3.
i+.
5.
10.
15.
20.
£5.
30.
60.
IdO.
Tu^JE\2
SlST-l-
VESSS
1 .
£.
3.
£t.
5 .
10.
15.
20.
25.
30.
60.
12*.
i?
-------
Table F-3C (Continued)
- ' v~-
Irn t lal Cir
VEAS3
2.
2.
...
5.
10.
15.
20.
£5.
30.
60.
120.
ElBtr"^,^
VEA = 5
1 .
jj.
*+.
5,
10.
15.
20.
£5.
30.
60.
120.
0r^.,flkTrJ.,_
C ism out i
Initial 3 .-•
T En-5
i ,
£.
3.
4.
5.
10.
15.
20.
c.'5.
30.
£0.
120.
PCB
Dl St f i D'-lt 1
YEARS
i .
c.
3.
H.
5.
15.
£0.
£5.
30.
£0.
120.
~~
oun^ter^oncent,
FRACTION
REFINING
C. Co
. 96' 3n 1600
. 93691 1000
. 906675100
. 877602200
. 849661300
. 72 192^300
. 613391200
.52117-+700
H^.2822000
. 376246700
. 141563100
. 020040100
on Coef f 1C lent =
FRACTION
C/Co
. 961095600
. 94££ 14900
. 923705000
. 905558600
. 8£0036600
. 74£591300
.672460100
.606952100
. 55i*+H 1800
. 304088100
. 092469600
--E
on Coefficient
oi.'ncwater Concer.tt
t- nhC l l UN
C/Co
. 9963392010
. 99666 1200
. 995025900
. 993373400
. 991723600
. 983515700
. 975375700
. 967303*00
. 959297400
.951357800
. 905081700
. 819.72900
on Coefficient
RE".HiMMG
C/Co
. 99952500C
. 99905020.0
. 996575600
. 99610*300
. 997c,27200
. 9 rl'^t*00 ^.'t!'
. 992896400
.99054E500
. 966192100
96564730'C
. 971894900
. 944579600
9. ' 0
-at ion (ug/1 )
GW CONC
(ug/ 1)
5.
5.
5.
4.
4.
4.
3.
3.
2.
=;.
1.
0.
15.00
GW CONC
(ug/1 )
£2.
22.
21.
21 .
19.
1 7.
15.
14.
13.
7.
2.
130.00
-sti.;.r, (uo/1)
GW CDNC
(ua/1)
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
630.00
GW CO^C
(ug.- 1)
0.
0'.
0.
0'.
0.
0.
0.
0.
0.
0.
0.
0.
PV REME
Distri but ion Coefficient 13i2iZi. ftC
Initlai Groundwater Concent rat ion (uo/ i)
YEflRS
1.
S..
3.
4.
5.
10.
15.
20.
£5.
30.
60.
120.
FRflCTION
REFINING
C/Co
.999769900
. 999539700
.999309700
. 999079700
. 998849700
. 997700800
. 996S53200
. 995406900
. 994262000
.993118300
. 986264000
.972756100
GW CONC
(ug/1)
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
FLUORfiNTHRENE
Dist ri but
Initial G
YEflRS
1.
£.
3.
4.
5.
10.
15.
20.
25.
30.
60.
120.
BE'MtO "HI H
D 1 st r i bi.it
Initial b
YEARS
1 .
2.
3.
4.
5.
10.
15.
20.
25.
30.
60.
120.
ion Coefficient
round water Concent rat
FRACTION
REfifilNING
C/Co
.999769930
. 999539700
. 999309700
.999079700
. 998849700
. 997700800
. 996553200
. 995406900
. 994262000
.993118300
. 986264000
.972756100
ion Coefficient
rounoi«at er Concent rat
FRACTION
REXfilMNG
C/Co
. 9'33d6k.iCti0
. ggsTtO'.otf
. 9996-t060iO
. 99952060'0
. 999401100
. 993802500
. 996204300
. 997606500
. 997008900
. 996-rll800
. 992836500
. 9S5724300
1300.00
ion (ug/1)
GW CQMC
(ug/1)
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
£500. 00
ion
-------
Table F-3C (Continued)
Dist r i a-.it ion Cc-ef fid er,t - 4. i?C
Initial 5 co u no water Concent rat ion ( ug/ 1)
flPSENIC
Distribution Coefficient = 140.08
14iZiiZii?. Initial Ground water Concent rat ion ( ug/' 1)
FRfiC'IGN
R2'vh-:i»;^G
C/Co
. 9£3364800
. 863718900
. 80£7i)9900
. 7-r£010400
. £932 15600
. 460&8a600
. 233i£7700
. 23;059<~-00
160: r~-I'0
. ; 110£7400
.0! £333960
.00015£l76
.<_'r. Coefficient
FS.hlTION,
C, Co
" " rc " r"
. S-riST-cOO
. Sl^SiSSOO
. 6&6070000
. 86£1027f 0
. 743£2l000
. 6HO>732.900
.55£377500
. 47£20&£0?
. -iC528£0*
. I£65'r2000
. 0£8-*0£f00
SW CO.\C
(ud/1)
13011.
12C32.
11£38.
10444.
970£.
6730.
4£6£.
2225.
££43.
1555.
173.
1=:-
10.00
(uc: ii"
305.
678.
af.2.
£2S.
7l2.
£ * 5.
530.
457.
2r*r.
16£.
£7.
YEARS
1.
£.
2.
4.
5.
10.
15.
£0.
£5.
30.
60.
1£0.
COPPER
Dist r i but ion
YERRS
1.
2.
2.
4.
5.
10.
15.
£0.
£5.
30.
60.
1£0.
FRACTION
REMAINING
C/Co
.997865400
. 935735500
.993610000
. 931483100
. 98937£700
. 978858300
. 968455700
. 358163600
. 947980900
. 937906400
. 879668400
.773816500
Coefficient
FRACTION
REMAINING
C/Co
.998505100
.99701£400
. 9955£190ei
.994033700
. 99£547700
. 985150900
. 977809300
. 9705££3l30
. 963£89700
.956111000
.914148£00
. 835666800
Gw CONC
(UQ/1)
18.
18.
18.
18.
18.
18.
17.
17.
17.
17.
16.
14.
£00. 00
GW CONC
*+03£200
. 93iO£7600
. 988108100
GW CONC
(UD/1)
"313.
318.
317.
316.
3l5.
30.
60.
1£0.
. 835721900
.6984-7600
£93.
F-33
-------
contaminants with distribution coefficients less than
about 10. Typically these are the higher molecular weight
volatile organics and the most mobile heavy metals (toluene
through ethylbenzene, and nickel and cadmium on the selected
contaminant list).
Tables F-3B and F-3C present the estimated groundwater con-
centrations versus time for the capping or 6-foot excavation
and 15-foot excavation alternatives. The results indicate
that groundwater pumped from the source area would have con-
taminant levels requiring treatment (before discharge) even
after 30 years of pumping. The higher weight volatiles,
base/neutrals, and acid extractables would require treatment
for the capping or 6-foot excavation alternative. Lower
levels of heavy metals would result from the 15-foot excava-
tion alternative, but also would require treatment before
discharge. The capping and 6-foot excavation alternatives
yield the same results because it was assumed the soil zone
above the water table would not contribute contaminants due
to the cap or soil removal.
These results show that groundwater pumping is not an effec-
tive source reduction remedial action except for the most
mobile volatile organics. Excavation is probably the best
source reduction action for relatively immobile contaminants.
MILL CREEK RESULTS
The impacts of Alternatives 1, 2, 3, and 5 on Mill Creek
water quality were qualitatively analyzed using the results
of the geochemical model. The analysis assumed that ground-
water contaminant mass loading to the creek is directly pro-
portional to total contaminant mass in soil and groundwater
(source strength). This was based on the earlier assumption
of linear contaminant desorption isotherms. It also was
assumed that natural groundwater flow to the creek is about
70 to 100 gpm.
Table F-4 shows the number of times the source strength would
have to be reduced to meet modified ambient water quality
criteria for metals in Mill Creek. The table was prepared
by dividing the estimated monthly concentrations in Mill
Creek (Table 3-65) by the modified 24-hour and maximum con-
centration criteria in Table F-5. Table F-5 is based on the
criteria presented in Table 3-47 assuming a hardness of
100 mg/L as CaCO.,. Because the water quality of Mill Creek
is primarily controlled by groundwater, especially in summer,
average background groundwater concentrations were substituted
if they were higher than the Table 3-47 values. The average
concentrations, based on a log-normal distribution, were
calculated using the lowest reported values for wells 30S,
31D, 32D, 33S, 33D, 36, 37, 38, 40, 41, 42, 43, and 44.
F-34
-------
Table F-4
RATIO OF ESTIMATED MILL CREEK AVERAGE CONTAMINANT
CONCENTRATIONS TO MODIFIED AMBIENT WATER QUALITY CRITERIA
Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Zn
0.44b
2.0
0.47
2.4
0.56
3.4
0.78
4.9
1.1
6.4
1.5
9.6
2.2
12
2.8
12
2.8
10
2.3
4.2
0.97
2.2
0.50
Cr+3
0.11
0.0010
0.12
0.0011
0.15
0.0014
0.20
0.0019
0.30
0.0028
0.39
0.0036
0.57
0.0053
0.73
0.0068
0.70
0.0066
0.59
0.0055
0.25
0.0023
0.14
0.0013
Cr+6
0.37
0.23
0.41
0.25
0.50
0.31
0.67
0.41
1.0
0.62
1.3
0.81
1.9
1.2
2.5
1.5
2.4
1.5
2.0
1.2
0.85
0.52
0.46
0.29
Cu
0.029
0.029
0.032
0.032
0.039
0.039
0.052
0.052
0.079
0.079
0.10
0.10
0.15
0.15
0.20
0.20
0.19
0.19
0.16
0.16
0.065
0.065
0.035
0.035
Ni
0.13
0.0065
0.14
0.0070
0.17
0.0087
0.22
0.011
0.33
0.017
0.43
0.022
0.65
0.034
0.83
0.043
0.80
0.042
0.68
0.035
0.28
0.015
0.15
0.008
Pb
0.052
0.007
0.057
0.0076
0.070
0.0093
0.10
0.013
0.14
0.019
0.18
0.024
0.28
0.037
0.36
0.048
0.35
0.047
0.29
0.039
0.12
0.016
0.061
0.0081
Cd
0.54
0.50
0.61
0.56
0.75
0.70
1.0
0.93
1.5
1.4
1.9
1.8
2.9
2.6
3.6
3.3
3.6
3.3
3.0
2.8
1.3
1.2
0.64
0.60
a
24-hour criteria ratio.
b
Maximum criteria ratio.
Note: See Table F-5 for modified criteria and Table 3-65 for estimated Mill Creek
concentrations.
F-35
-------
Chromium +3 and +6 were set equal to the reported total chro-
mium because separate values were not reported. The ratios
in Table F-4 indicate that chromium +3, copper, nickel, and
lead are below the modified concentration criteria;
therefore, they were not considered further.
Table F-5
MODIFIED AMBIENT WATER QUALITY CRITERIA FOR METALS
IN MILL CREEK
Groundwater Criteria
Background 24-hour Maximum
Metal (yg/L) (yg/L) (yg/L)
Zinc 74 74* 321
Lead 23 23* 172
Nickel <40 96 1,844
Copper 75 75* 75*
Chromium3 13 44 (13*) 4,692 (21)
Cadmium 2.8 2.8* 3.02
Chromium +6 criteria in parentheses.
*Denotes values modified from Table 3-47-
Table F-6 shows the estimated times to meet modified ambient
water quality criteria in Mill Creek for the no action Alter-
native (Example Alternative 1). It shows that zinc, cadmium,
and chromium +6 would remain above the criteria within the
range of 60 to over 120 years.
Table F-7 shows the estimated pumping times to meet the mod-
ified criteria in Mill Creek after pumping stops for Alter-
natives 2 and 3. Capping or 6-foot excavation accounts for
a 58, 30, and 36 percent reduction in zinc, chromium +6, and
cadmium, respectively. The table shows that these metals
would remain above the criteria during summer within the
range of 30 to 120 years.
The effects of a 15-foot source removal in Area I/II (Alterna-
tive 5) also was evaluated. The results show that excavation
is sufficient by itself to reduce zinc, cadmium and chro-
mium +6 contamination to the levels required to meet modified
creek water quality criteria. Zinc, chromium, and cadmium
would be reduced about 93, 94, and 95 percent, respectively.
Some residual contamination would remain in the unexcavated
F-36
-------
Table F-6
ESTIMATED TIME TO MEET MODIFIED 24-HOUR AND MAXIMUM
AMBIENT WATER QUALITY CRITERIA IN MILL CREEK
(NO ACTION ALTERNATIVE)
Month
January
Zn
Time (years)
Cd
Cr+6
February
30-60
March
60-120
April
60-120
May
June
July
August
September
October
November
December
60-120
5-10
>120
25-30
>120
30-60
>120
60-120
>120
60-120
>120
30-60
60-120
30-60
15-20
10-15
30-60
30-60
30-60
30-60
60-120
30-60
30-60
30-60
30-60
30-60
5-10
4-5
_
1
>120
>120
60-120
>120
>120
>120
>120
>120
60-120
-
_
Based on 24-hour criteria.
Based on maximum criteria.
Note: "-" denotes modified criteria would be met without
remedial action.
F-37
-------
Month
Table F-7
ESTIMATED PUMPING TIME TO MEET MODIFIED 24-HOUR
AND MAXIMUM AMBIENT WATER QUALITY CRITERIA
IN MILL CREEK AFTER PUMPING STOPS
(ALTERNATIVES 2 AND 3)
Time (years)
January
February
March
Zn
a
"b
Cr+6
Cd
April
May
25-30
30-60
June
July
August
September
October
November
December
60-120
60-120
120
10-15
60-120
10-15
60-120
30-60
60-120
>120
20-25
>120
20-25
60-120
5-10
5-10
25-30
25
30-60
30-60
30-60
30-60
30-60
25-30
Based on 24-hour criteria.
Based on maximum criteria.
Notes: "-" denotes modified criteria would be met without
pumping.
Mill Creek water quality should meet criteria dur-
ing pumping.
F-38
-------
portions of Areas V and IX. This would be partially miti-
gated by dewatering pumping and treatment during the approx-
imate 4-year excavation process.
The predicted groundwater concentrations in Tables F-3B and
F-3C should not be compared with the Mill Creek impact as-
sessment results shown in Tables F-6 and F-7. The predicted
groundwater concentrations are representative of the site
average source, whereas the Mill Creek impacts are represen-
tative of conditions at the source edge. The Mill Creek
results also reflect an integration of all the physical and
geochemical processes that affect water quality changes.
GROUNDWATER QUALITY STANDARDS AND CRITERIA
Because the shallow aquifer may possibly be used as a future
potable water source, groundwater quality in Area I/II was
compared to the drinking water standards, criteria, and can-
cer risk levels discussed in Chapters 2 and 4. The contami-
nants considered all have published standards, criteria, or
cancer risk levels. They include 17 of the 23 indicator
contaminants discussed earlier in this appendix plus 12 addi-
tional contaminants. The known or suspected carcinogens are
listed in Table F-8 and noncarcinogens in Table F-9.
The standards, criteria, and cancer potencies include the
federal drinking water standards, acceptable daily intakes
(ADI's), excess lifetime cancer risks, drinking water qual-
ity criteria for human health, and suggested no adverse re-
sponse levels (SNARL's). The federal and state drinking
water standards are legally enforceable requirements and
apply to municipal and community drinking water systems.
Standards have been set for several priority pollutant me-
tals and a single indicator organic compound (chloroform).
The ADI's, water quality criteria, and SNARL's are advisory,
but address more of the organic priority pollutants found at
Western Processing.
The ADI's assume ingestion of 2 L/day, and the excess life-
time cancer risks were calculated using the worker scenario
discussed in Chapter 4. The mean observed onsite ground-
water concentrations are those used in Chapter 4. These
concentrations differ slightly from those presented earlier
in this appendix. However, the differences do not signifi-
cantly affect the results of this analysis.
The percent reduction needed to achieve a particular stan-
dard, criterion, or cancer risk level was first calculated.
The reductions were then compared to Table F-3A values to
estimate the years of pumping at 100 gpm needed to achieve
the target levels. The percent reductions and estimated
number of years are presented in Tables F-8 and F-9.
F-39
-------
Table F-8
REDUCTION IN GROUNDWATER CONCENTRATIONS REQUIRED TO ACHIEVE
SPECIFIED STANDARDS OR CRITERIA FOR KNOWN OR SUSPECTED CARCINOGENS
(Example Alternatives 2 and 3)
Mean Observed Excess Lifetiie Cancer Riskll » 18-5)le) Excess Lifetiie Cancer Riskll » 18-6)(e)
Benzene (a) 8,843
Chlorofon (b) 2
1,2-Dichloroethane 8.38
tethylene chloride (c) 34
Tetrachloroethene (c) 8.847
1,1,2-Trichloroethane (c) 8.8183
Trichloroethene (c) 18
Vinyl cnloride la) 8.023
Arsenic 8,817
Total
Current X Reduction to Pimping
Level Achieve TarjetTiielyrHf.g)
2.4E-«5
1.6E-83
2.3E-84
2.3E-84
l.BE-85
5. £-86
3.7E-83
4.4E-86
2.8E-43
58.89
99.37
95.56
95.71
44.13
8.88
99.73
8.88
99.64
(5
(28
(5
(5
(15
—
(48
—
Never
Current * Reduction to Puiping
Level Achieve Target Ti«e(yrl(f,i|)
2.4E-85
1.6E-83
2.3E-84
2.3E-84
1.8E-85
5.2E-86
3.7E-83
4.4E-86
2.8E-83
95.89
99.94
99.56
99.57
94.41
88.67
99.97
77.16
99.96
(5
(2«
(5
(5
(15
—
(48
—
Never
B.6E-83
99.99
8.6E-83
99. SB
I
*>
O
Cheiical
Benzene (a)
Chloroform (b)
1,2-Oichloroethane
Methylene chloride (c)
Tetrachloroethene (c)
1,1,2-Trichloroethane Ic)
Trichloroethere (c)
Vinyl chloride (al
Arsenic
Mean Observed
Dncite
Uiblvc
Concentration
(•g/L) (d)
8.843
2
8.38
34
8.847
8.88B3
18
8.«£3
8.817
Drinking Water Standard Suggested No
Standard * Reduction to Pwping 18-day J-Reduction t
(•9/LI Achieve Std. Tiie(yr) (i|/LI Achieve Crit.
8.23 8.88
8.1 95.24 (15 8.82 99.85
8. IB &tt
8.2 9B.S9
e.»5 8.88 -
Adverse Response Level (SNARL)
Puiping
Tiielyr)
(15
_
(38
Longer-ten t-Reduction t
lig/L) Achieve Crit.
8.87 8.88
8.82 S7.4S
8.8B 99.56
Puiping
TiK(yr)
(28
(48
(a) Cancer potency estimated fra the aibient Hater quality criteria docuient.
(b) Drinking Mater standard is for su» of concentrations of
chlorofon, broMdichloroiethane, dibroHchloroiethane and brwofor*.
(c) IARC believes that there is inadequate evidence to classify
as a huian carcinogen.
(d) Nondetects are set equal to the detection h.it.
(e) Lifetiie itater ingestion rate; 8.816 liters per kilograi body Height per day
Annual exposure fraction: 8.68
If) Puiping tin notes: < = less than; ) - greater than; )) = very iuch greater than
When a piuping tiK exceeds 38 years but is less than sow nuaber,
the puiping tiie is betHeen 38 years and the tiie shown.
(g) Puiping tiies assuie that a cap is in place and/or all materials in
the unsaturated zone have been renved. Tiies are based on Table F-3fl I F-3B.
-------
Table F-9
REDUCTIONS IN GROUNDWATER CONCENTRATIONS REQUIRED TO ACHIEVE
SPECIFIED STANDARDS OR CRITERIA FOR NONCARCINOGENS
(Example Alternatives 2 and 3)e
Mes
Cor
Cheiical 1
1, 1-Dichloroethane
Trans-l,2-dichloroeth
2,4-DiKthylphenollb)
Ethylbenzene
Phenol
Bis(2-ethylhe»yl)phth
Toluene
1, 1, 1-Trichloroethane
Boron
Cadiiui (c)
Chroiiui (assuied VI)
(assuwd III
Cobalt
Copper (b)
Cyanide
Iron
Lead
Manganese
Mercury
Nickel (g)
Zinc (b),ih)
in Observed
Onsite
centration
•g/L)(d)
8.62
14
8.93
8.8886
75
8.85
8.57
7.6
5.9
1.1
1.5
1.5
8.42
8.74
8.19
85
8.21
89
8.8877
11
93
Mater Quality Criteria for
Acceptable Daily Intake(a) Drinking Mater Standard Huian HealthlDrinking Uater Only) Suggested No Adverse Response Level (SNflRL)
Value I Reduction to
(ig/day) Achieve ADI (a)
1.6
7
42
38
38
8.17
8.175
125
7.6
8.1
8.82
1.5
8.88
95,33
8.88
8.88
8.88
NA
92.27
94.17
8.88
NA
NA
8.88
NA
76.19
NA
8.88
93.18
Puiping Standard * Reduction to Puiping Criteria * Reduction to
Tiie(yr) (ig/LI Achieve Std. Tiie(yr) lig/L) Achieve Crit.
—
(5
—
—
—
)128 8.81
Never 8.85
—
—
Never 8.85
8.882
<128(f)
8.4
1.4
3.5
21
15
19
99.89 »128 8.8154
96.67 Never 8.85
178
1
8.2
76.19 Never 8.85
8.88 - 8.81
8.8154
5
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
8.88
Puiping 18-day H-Reduction to Puiping Longer-ten It-Reduction to Puiping
Tiie(yr) («g/L) Achieve Crit. Tiie(yr) dg/L) Achieve Crit. Tiee(yr)
8.27 8.88 (18
(18
—
(5
—
- 2.2 8.88
—
H28
Never
—
—
—
Never
—
1128
1)128
8.34 8.88 (18
1 8.88 (15
la) Assuied ingest ion of 2 L/day.
(b) Uater quality criteria based on organoleptic considerations.
(c) ADI is not strictly an ADI but represents an oral threshold effect
level for stokers.
(d) Assmes nondetects are set equal to the detection liiit.
(e) The puiping tiies shown assuie a cap is in place and/or all uterials in
the unsaturated zone are reioved. Tiies are based on Table F-3A t F-3D.
If) Puiping tiie notes: ( = less than; ) = greater than; » - iuch greater than.
When a puiping tiie exceeds 38 years but is shorn as less than so«e nuiber,
the puiping tiie is betieen 38 years and the tiie shewn.
(g) The nickel detection hut in background saiples was too high to coipare
actual nickel background concentrations to criteria. If background is
is approniiately 48 ug/L, then puiping tiie is (128 years.
(h) The background concentration of zinc is above the Hater quality criteria
for drinking nater(8.874(bgnd) vs. 8.853(crit.) both ig/L). Puiping
UK to achieve background is still 1128 years. See also note (b).
-------
Four of the contaminants in Tables F-8 and F-9 that currently
exceed criteria are not listed in Table F-3A. To evaluate
these contaminants, their distribution coefficients were ob-
tained as described earlier in this appendix. The pumping
time for each contaminant was then interpolated from
Table F-3A. These contaminants and their distribution co-
efficients are:
Benzene 0.89
1,2-Dichloroethane 0.19
1,1,2-Trichloroethane 0.91
Vinyl chloride 0.025
A remedial action similar to Example Alternative 2 or 3
would reduce the concentrations of organic contaminants in
the groundwater in Area I/II to drinking water standards in
less than 15 years, and to the SNARL for longer term use in
approximately 40 years. Forty years of pumping would also
reducethe lifetime excess cancer risk for organics to
1 x 10 for the worker scenario.
Example Alternative 2 or 3 would not be effective in achiev-
ing drinking water standards for some metals. The lead and
chromium (if hexavalent) concentrations in Area I/II ground-
water would for all practical purposes never be reduced to
drinking water standards, and cadmium would require more
than 120 years of pumping. Zinc and nickel water quality
criteria are below background groundwater concentrations;
therefore, backgrounds were used as the appropriate target
levels. Approximately 120 years of pumping would reduce
zinc and nickel concentrations to background.
A slightly different approach was taken to estimate the ef-
fect of the 15-foot excavation and temporary dewatering of
the construction area included in Example Alternative 5.
For the contaminants with federal drinking water standards
or SNARL's, the percent reduction achieved by excavation was
calculated by dividing the contaminant mass removed from the
saturated zone by the total contaminant mass in the sat-
urated zone using data in Table F-1B. The groundwater con-
centrations were assumed to be directly proportional to
source strength (contaminant mass in soil) as in the Mill
Creek discussion. The percentage reduction achieved by
excavation was then compared to the percentage reduction
required to meet the target levels in Table F-9.
The excavation component of Example Alternative 5 would re-
duce the concentrations of lead, chloroform, tetrachloro-
ethene, toluene, and 1,1,1-trichloroethane in Area I/II to
below the federal drinking water standards or SNARL's. Exca-
vation and groundwater extraction would reduce trichloroe-
thene and trans 1,2-dichloroethene concentrations to below
the SNARL's. Cadmium and chromium (if hexavalent)
F-42
-------
may not be reduced sufficiently by Example Alternative 5 to
achieve federal drinking water standards.
BATTELLE GROUNDWATER FLOW/TRANSPORT MODEL
The groundwater flow and contaminant transport system was
modeled by Battelle (Bond et al., September 1984) . This
report is currently being extensively revised with a comple-
tion date estimated to be early 1985. The purpose of the
modeling was to evaluate the overall effectiveness of each
example remedial action in reducing contaminant concentra-
tions in Mill Creek. To date, only trichloroethene (TCE)
reductions have been simulated. The following brief discus-
sion is based on preliminary results obtained from Battelle
prior to issuance of their final report. The mechanics of
model development and discussion of assumptions and limita-
tions will be in the final Battelle report.
FLOW MODELING
The model area is 2,800 feet wide and 4,000 feet long. The
Western Processing site lies just south of the model
region's center. The model approximates site conditions to
a depth of 100 feet below the water table. Simplifying as-
sumptions were necessary because of hydrogeologic complexity.
The initial, boundary, and calibration data, however, were
all consistent with the results of the field investigations.
Subsurface conditions were represented as a two-layer system.
The upper layer- extending to 40 feet beneath the water table,
was classified as clay, silt, and sand. Beneath this layer
were more permeable sands extending to 100 feet below the
water table.
Horizontal and vertical hydraulic conductivities used in the
model are listed below. Vertical hydraulic conductivities
were assumed to range from one-tenth to one-twentieth of
horizontal hydraulic conductivities as typically reported in
the literature. The use of one-twentieth the horizontal
hydraulic conductivity for the vertical component of the
shallow unit is supported by the complex stratification that
restricts vertical flow. The hydraulic conductivities used
in the model are:
Depth
Below
Groundwater K-Horizontal K-Vertical
Layer (feet) (ft/day) (ft/day)
Sand, silt, and clay 0-40 2.5 0.13
Sand 40-100 25 2.5
F-43
-------
Mill Creek and the east drain were simulated using a stream
boundary option that considers the stream surface elevation,
stream width, bed thickness, and bed permeability. Prelimi-
nary model results indicate a flow increase for Mill Creek
in the model area of 0.3 cfs, which is close to the 0.5 cfs
measured in the field by USEPA in May 1982.
SOLUTE TRANSPORT MODELING
Trichloroethene (TCE) was chosen for transport modeling be-
cause it was widespread at high concentrations and because
the geochemistry of TCE is better understood than many of
the other site contaminants. The initial TCE distribution
and total mass are consistent with the results of the con-
taminant source quantification analysis discussed earlier in
this appendix.
Model results indicate that under existing conditions Mill
Creek is the primary receptor of TCE leaving Western Pro-
cessing. The east drain receives the remainder. The
calculated mass flux of TCE to the creek is about 0.7 pound
per day based on current assumptions of parameters that
affect migration rates.
The percent reduction during the 1988 to 1993 timestep rela-
tive to the no action alternative during the 1983 to 1988
timestep for Example Alternatives 1, 2, 4, and modified 5
(i.e., no-action; cap with pump and treat; PRP; and 6-foot
source removal with pump and treat) is presented below.
RELATIVE EFFECTIVENESS
Alternative Percent Reduction
1 (no action) 25
2 (cap, pump and treat) 96
4 (PRP) 70
5 (excavate, pump and treat) 95
It must be noted that TCE is currently below applicable am-
bient water quality criteria in Mill Creek. Moreover, be-
cause different contaminants will migrate at different rates
(different R values), the relative TCE reductions may not be
applicable to the other contaminants.
F-44
-------
Appendix G: Methods, Assumptions, and
Criteria for Groundwater
Treatment Process Selection/ Design
-------
Appendix G
METHODS, ASSUMPTIONS, AND CRITERIA FOR
GROUNDWATER TREATMENT PROCESS SELECTION/DESIGN
This section is divided into three subsections. The first
subsection discusses technical considerations that impact
the scope and cost of the groundwater treatment system. The
second subsection discusses individual treatment technologies
and their advantages and disadvantages for treating Western
Processing groundwater. The third subsection illustrates an
example groundwater treatment system that was used to develop
order-of-magnitude costs for Alternatives 2, 3, and 5 in
Chapter 6.
TECHNICAL CONSIDERATIONS
The process requirements, equipment sizing, and capital and
operating cost of a groundwater treatment system depend pri-
marily on the following four factors:
1. Groundwater flow rate to the treatment system
2. Groundwater quality
3. Treatment objectives
4. Duration of treatment
Each factor is discussed in the sections below.
FLOW RATE
The flow rate to the groundwater treatment system is con-
trolled by hydrogeologic factors and/or by hydraulic limi-
tations imposed by various discharge receptors.
Based on available hydrogeologic information, the ground-
water collection system can be pumped continuously at a
maximum rate of 0.5 gpm per well point. Therefore, for
Alternatives 2 and 5, the maximum flow rate is about 170 gpm
(340 well points). For Alternative 3 the maximum is 85 gpm
(170 well points). Groundwater can be extracted at a slower
rate by turning off portions of the well field.
There are several possible receptors for treated groundwater,
including the municipal sewer system, Mill Creek, the Green
River, and the groundwater aquifer below the site.
The Municipality of Metropolitan Seattle (Metro), which has
primary authority over the municipal sewage collection and
treatment system in the Seattle area, has indicated that for
hydraulic reasons discharge from Western Processing to the
municipal sewer system may be restricted to 140,000 gallons
per day (approximately 100 gpm). It is possible that addi-
tional hydraulic capacity could be gained by increasing sewer
G-l
-------
diameters or modifying pump stations, but this possibility
was not considered in this feasibility study. Also, further
investigation may reveal that additional hydraulic capacity
is available without modifications to the sewer system.
According to the Washington State Department of Ecology (WDOE),
any point source discharge from Western Processing to either
Mill Creek or the Green River must be restricted to no more
that 15 percent of the stream discharge rate. In Mill Creek,
measured flows during summer have been as low as 2 cfs, mean-
ing that during this time only 194,000 gallons per day, or
135 gpm, could be discharged. High flows could be accepted
during most of the year. The Green River could accept the
maximum flow of 170 gpm from the treatment system at all
times.
With a properly designed groundwater recharge system there
should be no flow restrictions if treated groundwater were
to be returned to the aquifer.
GROUNDWATER QUALITY
Available data show that existing groundwater quality is
highly variable throughout the site, especially with depth.
Also because of physical and geochemical factors groundwater
quality will be variable over time. For this reason, the
required treatment level will vary as a function of time.
Representative "worst case" initial groundwater quality for
the treatment system was estimated using site averages for
each constituent developed from the contaminant source
quantification analysis discussed above. Table G-la shows
average organic and inorganic contaminant concentrations for
Areas I and II with a 0- to 6-foot excavation depth.
Table G-lb shows average concentrations for Areas I and II
with a 15-foot excavation depth. The values represent a
typical composition that might be achieved during the early
stages of pumping.
No data are available for several parameters that could sig-
nificantly affect the groundwater treatment system. For
example, no groundwater samples were analyzed for 5-day bio-
logical oxygen demand (BODS), chemical oxygen demand (COD),
or total organic carbon (TOC). Without these parameters, it
is impossible to accurately predict chemical oxidant dosage
or to determine whether biological treatment is a viable
option. Additional analyses also are necessary to determine
the concentrations of major cations and anions present in
the groundwater. Without these data, any estimates of
precipitation chemical requirements, sludge generation rates,
and equipment sizing can only be tentative.
G-2
-------
Table G-la
GROUNDWATER CONTAMINANT CONCENTRATIONS, AREA I/II
WESTERN PROCESSING, KENT, WASHINGTON
(WITH A 0- TO 6-FOOT EXCAVATION)
Site Average
(in yg/L)
Volatiles
Methylene chloride 52,000
Trichloroethene 16,000
Trans 1,2-dichloroethene 7,700
1,1,1,-Trichloroethane 8,700
Chloroform 2,200
Toluene 820
Tetrachloroethene 50
Ethylbenzene 10
Nonvolatiles
Phenol 42,000
Bis(2-ethylhexyl)phthalate 0
Naphthalene 15
Metals
Zn 121,000
Ni 15,000
Cr 2,200
Cd 1,500
Cu 1,000
Pb 290
As 19
G-3
-------
Table G-lb
GROUNDWATER CONTAMINANT CONCENTRATIONS, AREA I/II
(WITH A 15-FOOT EXCAVATION)
Site Average
(in ug/L)
Volatiles
Methylene chloride 49,000
Trichloroethene 7,200
Trans 1,2-dichloroethene 160
1,1,1,-Trichloroethane 1,000
Chloroform 2,000
Toluene 320
Tetrachloroethene 5
Ethylbenzene 5
Nonvolatiles
Phenol 1,500
Bis(2-ethylhexyl)phthalate 0
Naphthalene 23
Metals
Zn 118,000
Ni 14,000
Cr 320
Cd 960
Cu 790
Pb 270
As 18
G-4
-------
There is a high probability of reactions taking place that
could affect the removal efficiency, chemical dose require-
ment, and overall viability of various treatment processes
due to the presence of numerous tentatively identified and
unidentified compounds in the groundwater. The only way to
determine the treatability of the groundwater is through
bench-, pilot-, and/or full-scale testing of various treatment
processes. At an absolute minimum, bench- or pilot-testing
will take 3 to 4 months to complete. Without bench- and/or
pilot-testing, the effectiveness of most treatment processes,
particularly chemical and biological oxidation, activated
carbon adsorption, and heavy metals precipitation, cannot be
assessed until the full-scale system is operational.
TREATMENT OBJECTIVES
The objectives of groundwater treatment can be based on
technical requirements (e.g., activated carbon treatment),
percent removal requirements (e.g., 99 percent removal of
all priority pollutants), or effluent concentration limita-
tions (e.g., Metro pretreatment requirements).
The effluent concentration limitations are different for
each potential discharge point. For discharge to the Metro
sanitary sewer system, preliminary effluent limitations are
shown in Table G-2. The effluent limitations were taken
from the current Metro discharge permit allowing discharge
of treated storm runoff from Western Processing to Metro.
Metro engineers have indicated that the effluent limitations
would probably remain the same for treated groundwater, but
they could not guarantee this until the actual permit appli-
cation is processed. The current permit expires in August
1985, and it is possible that different limits might be
imposed.
The Washington State Department of Ecology (WDOE) regulates
discharge of liquid wastewater into Mill Creek or the Green
River. The WDOE bases its NPDES discharge requirements on
USEPA ambient water quality criteria for the protection of
aquatic life or human health. These criteria are shown in
Table G-3. The maximum allowable concentration cannot be
exceeded in the effluent. In addition, 24-hour criteria
(Column 3 of Table G-3) cannot be exceeded at the edge of
the mixing zone. The mixing zone itself cannot be more than
15 percent of the stream width. This limitation could
severely restrict the degree of initial mixing obtainable in
Mill Creek.
The effluent requirements necessary for discharge to a
groundwater recharge/recirculating system would likely be
the same as the ambient water quality criteria 'used for Mill
Creek or the Green River.
G-5
-------
Table G-2
PRELIMINARY LIMITATIONS FOR DISCHARGE TO
METRO SANITARY SEWER SYSTEM
Compounds
Total oils and greases
pH range
Cyanide (total)
Total toxic organics (TTO)
Arsenic (As)
Cadmium (Cd)
Chromium (Cr)
Copper (Cu)
Lead (Pb)
Mercury (Hg)
Nickel (Ni)
Zinc (Zn)
Daily Maximum Concentration
100 mg/L
5.5-12.5
2.0 mg/L
2.13 mg/L
1.0 mg/L
1.2 mg/L
6.0 mg/L
3.0 mg/L
,0 mg/L
mg/L
6.0 mg/L
5.0 mg/L
Table G-3
CURRENT AMBIENT WATER QUALITY CRITERIA
FOR NPDES DISCHARGE
Compound
Cd
Cr
Cu
Pb
Ni
Zn
Chloroform
1,1,1-Trichloroethane
Trans-1,2-dichloroethene
Tetrachloroethene
Trichloroethene
Toluene
2,4-Dimethylphenol
Maximum
Allowable
Concentration
in Effluent
(pg/L)
3
21
22.2
172
1,844
321
28,900
18,400
11,600
5,280
45,000
17,500
2,120
02
Maximum Average
Concentration
at Edge of
Mixing Zone
3
96
47
1,240
840
0.0025
0.29
5.6
8
Assumes hardness to be 100 mg/L as CaCO3.
G-6
-------
Using the maximum allowable concentrations (that are likely
to be less severe for Mill Creek than the 24-hour average
concentrations), the degree of additional treatment required
to remove various heavy metals can be calculated. Table G-4
shows the additional removal efficiency required for various
heavy metals. (Specific criteria are not available to com-
pare organics.) The table shows that an extremely high-
efficiency heavy metals removal system will be required for
discharge to Mill Creek. This system is likely to include
expensive treatment processes, such as multiple ion exchange
units. It is likely that the amortized capital and operating
cost of additional treatment to allow discharge to Mill Creek,
the Green River, or to groundwater will exceed the user fee
for discharging to the Metro system, which is estimated to
be approximately $150,000 per year. For this reason, dis-
charge to Metro has been used to illustrate the treatment
level that might be required. The only drawback of discharg-
ing to Metro will be the 100-gpm hydraulic restriction cur-
rently imposed on wastewater flow. However, it is likely
that this restriction would not interfere with implementation
of remedial actions. Additional capacity might be also
obtainable by increasing the capacity of the sewage collec-
tion system, or by additional treatment and use of another
discharge point in excess of 100 gpm.
Table G-4
DEGREE OF INITIAL TREATMENT REQUIRED
FOR DISCHARGE INTO MILL CREEK VERSUS METRO
Minimum Percent Increase in
Removal Efficiency Required
Compound For Discharge to Mill Creek
Cd 99.7
Cr 99.7
Cu 99.3
Pb 94.3
Ni 69.3
Zn 93.6
PUMPING DURATION
USEPA has indicated that one goal for remedial actions is
that pumping and groundwater treatment continue until ground-
water concentrations are lowered to meet ambient water qual-
ity criteria. Tables G-5a and G-5b show the expected
Area I/II average groundwater concentrations at the end of
30 years at 100 gpm for 0- to 6-foot and 15-foot excavations,
respectively. These estimates were on the geochemical model
presented earlier in this appendix. The analysis predicts
that most volatile organics will be reduced to levels in the
G-7
-------
Table G-5a
PREDICTED AREA I/II GROUNDWATER CONCENTRATIONS
AFTER 30 YEARS OF PUMPING AT 100 GPM
(WITH 0- TO 6-FOOT EXCAVATION)
Volatiles
Methylene chloride
Trichloroethene
Trans-1,2-dichloroethene
1,1,1-Trichloroethane
Chloroform
Toluene
Tetrachloroethene
Nonvolatiles
Phenol
Bis (2-ethylhexyl)phthalate
Heavy Metals
Cd
Cr
Cu
Ni
Pb
Zn
Expected Average
Concentration (pg/L)
Initial
52,000
16,000
7,700
8,700
2,200
820
50
42,000
0
1,500
2,200
1,000
15,000
290
121,000
After 30 Years
0
110
0
90
0
100
14
0
0
800
2,070
970
3,170
290
79,400
G-8
-------
Table G-5b
PREDICTED AREA I/II GROUNDWATER CONCENTRATIONS
AFTER 30 YEARS OF PUMPING
(WITH 15-FOOT EXCAVATION)
Expected Average
Concentration (ug/L)
Volatiles Initial After 30 Years
Methylene chloride 49,000 <0.1
Trichloroethene 7,200 51
Trans-1,2-dichloroethene 160 <0.1
1,1,1-trichloroethane 1,000 10
Chloroform 2,000 <0.1
Toluene 320 41
Tetrachloroethene 5 I
Nonvolatiles
Phenol 1,500 <0.1
Bis(2-ethylhexyl)phthalate 0 0
Heavy Metals
As 18 17
Cd 960 511
Cr 320 300
Cu 790 765
Ni 14,000 2,958
Pb 270 270
Zn 118,000 77,453
G-9
-------
low mg/L range or lower. Phenols are predicted to be at
nondetectable levels. However, phthalates (and nonvolatile
chlorinated organics, which are not shown) will most likely
still be present at detectable levels in the groundwater.
Heavy metals will also be present in the groundwater, at
levels above ambient water quality criteria.
For ambient water quality criteria to be met, pumping and
groundwater treatment will probably be needed for more than
30 years. However, because the effect beyond 30 years on
the present worth economic analysis is minimal, only a
30-year planning horizon was used in this feasibility study.
AVAILABLE GROUNDWATER TREATMENT TECHNOLOGIES
As described in Chapter 5, there is a wide range of ground-
water treatment technologies that can be employed to reduce
contaminant concentrations to acceptable levels for discharge
to Metro, surface water, or groundwater.
This section briefly describes the primary treatment alter-
natives that were evaluated. The treatment alternatives are
divided into those primarily intended for metals removal and
those for organics.
HEAVY METALS REMOVAL
The basic removal processes for metals are precipitation and
concentration. The following treatment processes were eval-
uated for applicability to Western Processing.
o Alkaline precipitation
o Sulfide precipitation (Sulfex Process)
o Ion exchange
o Reverse osmosis
Alkaline Precipitation
Most metal hydroxides are insoluble at elevated pH levels.
Lime, sodium hydroxide, and magnesium hydroxide are alkaline
agents used to raise pH to precipitate metals. In this pro-
cess, the alkaline agent is added to water to achieve pH
levels from 8 to 11 to precipitate metal hydroxides. Lime
is the most commonly used alkaline agent in metals precipi-
tation because of low cost, relative ease of handling, and
good dewatering characteristics of the sludge. Concentration
reduction of metals actually attainable is a function of
lime dosage, operating pH, the presence of complexing agents
such as ammonia and organics, and the means employed to
remove the insolubles from the water. Lime precipitation is
effective for removing trivalent chromium, but ineffective
for removing hexavalent chromium. If there are significant
amounts of hexavalent chromium present, it will have to be
reduced chemically or electrochemically prior to alkaline
precipitation for this treatment process to be effective.
G-10
-------
Advantages and disadvantages of lime precipitation can be
summarized as follows:
Advantages
Disadvantages
o Proven technology
o Low capital cost
o Moderate operating cost
o Continuous method
o Moderate sludge volumes
Must be followed by fil-
tration to achieve low
concentrations
Dewatering and disposal
of potentially hazardous
sludge required
On wastes above approxi-
mately 1,500 mg/L sul-
fate, calcium sulfate
may precipitate and
cause severe scaling
problems and/or add sig-
nificantly to the volume
of sludge requiring
disposal
Sulfide Precipitation
Almost all metal sulfides are less soluble than metal hydrox-
ides. The use of sulfide ion as a precipitant for removal
of heavy metals can, therefore, accomplish more complete
removal than the use of hydroxide for precipitation.
The Sulfex Process, developed by Permutit, uses iron sulfide
to provide sulfide ion. Sufficient iron sulfide is added so
that all of the heavy metals present can be converted to
sulfide. By maintaining pH in the 8 to 9 range, excess iron
in the system will precipitate as iron hydroxide. For an
acidic waste, an alkali source is needed for maintaining
favorable pH conditions. The Sulfex Process is generally
less cost-effective than lime precipitation when total in-
fluent metal concentrations exceed 50 mg/L. The difficulties
encountered in removing hexavalent chromium by alkaline pre-
cipitation also apply to sulfide precipitation.
Advantages and disadvantages of sulfide precipitation are
summarized as follows:
Advantages
Most metal sulfides are
more insoluble than hy-
droxides, yielding better
theoretical removals
Disadvantages
Must be followed by fil-
tration to achieve low
concentrations
Chrome removals are no
greater than with lime
Potential exists for hy-
drogen sulfide evolution
G-ll
-------
Ion Exchange
The use of ion exchange resins to remove undesired constitu-
ents from waste streams is well established. Specific resins
for heavy metals removal have been developed by Rohm & Haas,
Dow, and Nalco, among others. In this process, most of the
metals are adsorbed on cationic resins, with the notable
exception of hexavalent chromium which is adsorbed onto anion
resin.
Performance of ion exchange systems is usually dependent on
pH, temperature, and ion concentrations. Pretreatment or
preconditioning of waste streams is often required to assure
satisfactory operation, especially when organics are present.
Significant quantities of spent regenerant requiring disposal
are produced during the regeneration of resins.
Advantages and disadvantages of ion exchange are summarized
as follows:
Advantages
High effluent quality
theoretically possible
Disadvantages
o High capital cost
o Requires pretreatment
o Produces a concentrated
solution that requires
disposal
o For wastes containing
many metals, in-bed
precipitates during
loading or regener-
ation can occur
Reverse Osmosis
Heavy metals can also be removed using reverse osmosis.
This process applies an external pressure to a solution in
contact with a semipermeable membrane to force water through
the membrane while dissolved solids and metals remain in the
waste brine reject solution. The reverse osmosis membranes
must be protected from fouling by prefiltration. Advantages
and disadvantages of reverse osmosis treatment are summarized
as follows:
G-12
-------
Advantages
High effluent quality
Disadvantages
o High capital and operat-
ing costs
o Requires pretreatment
o Produces a brine reject
flow that must be
treated, equal to 10 to
25 percent of raw water
flow
o High fouling potential
for mixed wastes
ORGANICS REMOVAL
Table G-6 contains a summary of the process technologies
evaluated for organics removal and identifies advantages and
disadvantages of each. Primary technologies considered are
described further in the following text.
Stripping
Volatile organic compounds can be removed from aqueous streams
by air or steam stripping. Steam stripping is technically
applicable but inappropriate for the Western Processing site
due to high energy costs. Air stripping usually is the least
expensive and most reliable method for removing volatile
organic compounds (VOC) from contaminated water and has been
used at a number of sites to clean up drinking water contam-
inated with these compounds. It is not effective for remov-
ing extractable organic compounds.
Air stripping takes place in a tower in which water cascades
down through packing material while air is forced up through
the packing. The large interfacial area created promotes
vapor-liquid equilibrium conditions that allow the volatiles
to escape into the flowing air stream. Generally the con-
centration of contaminants in the discharge air is below
emission standards, and it has usually been considered
environmentally acceptable to discharge this air directly to
the atmosphere. When emission control is required, the
volatile organics can be adsorbed in a vapor phase carbon
system on the vent. Such a requirement would significantly
add to the capital and operating costs.
Oxidation
Theoretically, all organic pollutants can be oxidized to
carbon dioxide. The methods normally used for oxidation are
chemical or biological.
G-13
-------
Chemical oxidation of organics in water involves chemical
reactions between the organic molecules and an oxidizing
chemical. The reaction may oxidize the original organic
molecule to a harmless compound, or may generate different
compounds, possibly even more toxic than the original mate-
rial. Oxidation products depend on the original molecule,
the type of oxidant used, and reaction conditions. Commonly
used chemical oxidants are ozone, hydrogen peroxide, chlo-
rine, and chlorine dioxide.
Ozone (O.j) is the triatomic form of oxygen (O-) . On a ther-
modynamic scale, ozone has approximately 1.5 times the oxi-
dizing potential of chlorine. Oxidation of organics in water
by ozone is normally carried out in contact tanks, in which
ozone is bubbled through a diffuser system. Multistage con-
tacting systems are usually required to properly utilize the
ozone. Recent developments in ozone-generating equipment
have reduced operating costs of ozonation to near that of
other chemical oxidants, but capital costs associated with
an ozonation system are high. Ozone must be generated at
the point of use.
Hydrogen peroxide (H_02) is a strong oxidant frequently used
in the chemical industry for waste treatment. Hydrogen per-
oxide is a relatively mild oxidant compared to ozone or
chlorine. The effectiveness of hydrogen peroxide on organics
other than phenol is not well reported. Hydrogen peroxide
and ozone have each been shown to be ineffective in oxidizing
some organics. While those oxidants have high oxidation
potentials, in some cases they do not possess the activation
energy required for reaction.
Chlorine (Cl?) is perhaps the most commonly used oxidizing
agent for wastewater treatment in the United States. The
technology of chlorine shipment, handling, measurement, and
application is well established and relatively reliable.
The use of chlorine to oxidize chlorinated hydrocarbon com-
pounds is ineffective on some of the chemical bonds, and
where effective, may generate additional chlorinated com-
pounds. These oxidation end-products may also require
removal because of their known or suspected toxicity.
Chlorine dioxide (C102) has been used experimentally to oxi-
dize phenolic compounds and other hydrocarbons in water.
Chlorine dioxide is an unstable gas which, like ozone, must
be generated onsite. Several chlorinated reaction products
have been identified from the oxidation reaction of hydro-
carbons with chlorine dioxide. Little is known about
G-14
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Table G-6
COMPARISON OF ORGANICS REMOVAL TECHNOLOGIES
PROCESS
COMPLEXITY
OF OPEJZATIOkJ
POO&A&ILJTf OF
AHHIEVIUC, OKIKED
RELATIVE.
RELATIVE
TYPE^ tPOTE-Ur/AL I/OLUMES OF RE-B/OueS &E*JERA1£O
ALKALIUE PRECIPITATION
AIR STRIPPluG
• SOLVEUT EXTRACTION
ADSORPTION
G.RAUULAR ACTIVATED
• POWDEftED ACTIVATED CARBOU
OUDEPEJJKMT PROCESS OK
ASAOJUtJCT TO HEA VY
METALS REMOVAL OK
BIOLOGICAL TKEATMEIJT)
OXIOAT/OU
• OZOAJE.
• WTDROSE.M PEKOK/DE
• C.HLOK.IUE.
• C.HLORJUE. DIOX.IOE
• OIOAJ£ WITH UV
PEROXIDE
WITH UV
MEMBRAUZ.
TREATMENT
LOW
LOW
HIGH
MODE.KATE.
ACTIVATED
. BIOLOGICAL
HIGH
LOW
HIGH
HIGH
Hl&t-t
HIGH
LOW
HIGH
MODERATE
LOW
LOW
LOW
MOO5.KATE.
LOW
LOW
LOW
LOW
HIGH
HI&H
MODERATE
MOD&WE
MODERATE
LOW
MODE ft ATE.
HIGH
MOOE.RA7E
MODE.RA7E.
HI&H
LOW
MODE-RATE.
HIGH
HIGH
HIGH
HIGH
MODERATE
HIGH
LOW
HIGH
HIGH
HIGH
MODEK&TE.
HIGH
HIGH
HIGH
MODERATE-
MODERATE.
RELEASE OP VAPOR &EARIUGOPF GASES
SOLVENT SEPARATION AUO H4UOLIUG
C.OMPOUUO
SELECTIVE. COMPOUND &REAJCTHROV6H
POTEUTIAL GEI-JERATIOU OP TOXIC REACTION PRODUCTS
POTEUTIAL GEUEKariOU OP TOXIC «E4C7VO»J PRODUCTS
POTENTIAL GEUEfiATlOU Of TOXIC REACTIOU PRODUCTS
POTEUTIAL &E/UEKATIOU OF TOXIC REACTIOU PRODUCTS
POTEJJTIAL &EJJE&OUT/OU OF- TDX/C KE4CTOU PRODUCTS
POTEUTIAL G&JERATICHJ Of TOXIC KEACTOJ PRODUCTS
MBt.1BK.AUE POULJUG
KUJLIUG
MBMBRAklE KXJL/UG
ORGAUICS Mr UHlBtT OR KJLL ORGAUI5MS
PRECIPITATION SLUDGE REQU/e/IU& DISPOSAL
POTENTIAL AIR caUTAMIkJATlOU
COUTAMUJATED SOU/OUT REQUIRItJG TREATMENT
OR. O/SPOSAL
SPEUT CAR3OU REOUIR/UG DISPOSAL OK
RE&E-UERATIOU COP^SITE)
SPEJJT CARBOU RESUIK.IUG DISPOSAL
tJOUE
/uo/ue
UOUE.
UOLJE
AJOUE
MODERATE. TO HIGH VOLUME REJECT STREAM
REQUIK.IU& SEPARATE.
SMALL VOLUME REJECT STKEAM REOLHRIUG
SEPARATE. TREATMENT
SMALL VOLUME. REJECT STREAM REQUlRHJS
SEPARATE TREATMENT
WASTE BIOLOGICAL SLUDGE
THE HEAVY METAL REMOVAL PROCESSES WILL
1UCIOEUTALLY REMOVE SOME
-------
oxidation of volatile chlorinated hydrocarbons with chlorine
dioxide, but it is likely that problems similar to those for
chlorine will also occur with chlorine dioxide.
Ozone has been used in combination with ultraviolet (UV)
radiation for oxidation of organics in water. The UV radia-
tion enhances the formation of chemical species that have a
higher oxidation potential than ozone alone. This technology
may be superior to ozone in oxidation performance while
retaining the advantage over chlorine in that no chlorinated
reaction products are formed.
Oxidation of organics in wastewater by hydrogen peroxide
(H_O2) and UV radiation has also been reported. A proprietary
process by Enercol, Inc., utilizes cavitational shock, an
organic catalyst, and UV radiation to form hydroxyl radicals
(OH") from hydrogen peroxide. The hydroxyl radicals are a
very powerful oxidizing species that react with organic mole-
cules, especially by reaction with single hydrogens on the
carbon chain or ring. Like ozone, hydrogen peroxide with UV
radiation may have the potential to be an effective oxidizing
system without the problem of chlorinated reaction products.
Pilot testing would be required to determine its actual
effectiveness.
Other oxidants include permanganate, chromate, bromine, and
persulfuric acid. None of these chemicals were considered
suitable for further investigation.
Biological oxidation is well-proven and relatively inexpen-
sive but may be difficult to operate in this application
because of potentially inhibitory and toxic effects of cer-
tain organic compounds and heavy metals, and because of waste
variability. A heavy metals pretreatment step, as previous-
ly described in this section, is a likely requirement for
successful biological treatment of Western Processing water.
It is possible that inhibitory organic removal by activated
carbon or other processes may also be required.
Aerobic, anaerobic, or a combination of both types of systems
are theoretically possible for organics removal. Anaerobic
systems are reportedly highly sensitive to feed variability
and inhibitory compounds and should not be considered further.
Standard aerobic oxidation, in its many variations as de-
scribed in sanitary engineering textbooks, is the preferred
approach.
One aerobic system, the PACT system, has technical merit for
this particularly difficult application. This process,
originally developed by DuPont and currently marketed by
Zimpro, uses powdered activated carbon as an additive to the
activated sludge process. In theory, the activated carbon
provides sites for biological growth and acts to adsorb the
G-17
-------
more refractory contaminants so that the biological organisms
can more easily oxidize them. The carbon is also believed
to protect the organisms from high loadings of highly con-
centrated toxic contaminants.
As with the chemical oxidation processes, biological oxida-
tion would have to be pilot tested to verify its applicabil-
ity and effectiveness for treating Western Processing
wastewater.
Adsorption
A common method of removing organics from water is adsorption
on activated carbon. This method has been used at hazardous
waste sites to clean up contaminated water. Generally, acti-
vated carbon is most effective for organic contaminants hav-
ing high molecular weight and low water solubility, polarity
and degree of ionization. Heavy metals can also be removed
by activated carbon, but at significantly lower removal rates
than are achievable with organics.
In water contaminated with a number of organics such as at
Western Processing, the effectiveness of carbon is less pre-
dictable because of preferential or competitive adsorption
behavior. Initially, high removals of most organics may be
achieved through a fresh bed of carbon. As the carbon be-
comes loaded with organics, contaminants with low adsorption
rates may begin to break through the carbon bed and appear
in the effluent. Because individual compound breakthrough
is governed by intrinsic chemical properties rather than by
desired order, it is commonly necessary to adsorb most of
the stream organics to obtain acceptable performance on the
target compounds. This leads to somewhat unpredictable, but
generally high, carbon dosages.
The two common commercial forms of activated carbon are
granular activated carbon (GAG) and powdered activated car-
bon (PAC). If GAG were used for this application, it would
be used in fixed or pulsed beds typical of those found in an
advanced wastewater treatment plant. Spent GAG may be re-
generated for reuse or disposed directly. Regeneration fa-
cilities can be onsite, or offsite through a contractor.
For this application, offsite regeneration would probably be
the preferred approach because direct disposal or onsite
regeneration are likely to be very expensive.
PAC can be used directly in its own process or as an adjunct
to another process. There are no theoretical limitations to
including PAC into the heavy metals removal processes previ-
ously described as a second additive for organics removal.
However, there is limited experience with this practice.
PAC could be added to its own flocculation and clarification
system to achieve organics removal. PAC can also be added
G-18
-------
to an activated sludge system as discussed above. PAC can
be regenerated or disposed of in a suitable landfill.
Solvent Extraction
Solvent extraction involves intimately contacting a liquid
stream with one or more solvents. The solvents preferen-
tially extract one or more components of the liquid stream.
The liquid stream and solvent are generally immiscible or
only slightly miscible. The solvents are recovered through
distillation or other techniques. Usually, residual solvent
is stripped from the raffinate stream (treated leachate in
this case). Different solvents will selectively extract
different organics. There also are solvents that will
extract certain metals. To find a solvent or solvents to
preferentially extract the compounds desired from a complex
leachate wastewater is almost impossible. For this reason
and because of high cost, this process will not be considered
further.
Membrane Separation
Separation of constituents from solutions can be achieved
through the use of polymeric membranes as in reverse osmo-
sis, electrodialysis, and ultrafiltration. Semipermeable
membranes allow the transport or separation of different
molecules depending on the material and pore sizes of the
membrane. The driving force through the membrane is pres-
sure, concentration, or voltage. The diffusion rate of
molecules is proportional to concentration. A relatively
concentrated waste stream is generated that contains most of
the separated organics.
All membrane processes are somewhat imperfect with respect
to organic separation, so the "dilute" stream will still
contain organics. Previous experience with membrane systems
indicates that severe organic fouling is likely unless sophis-
ticated pretreatment steps are used and precise operating
conditions are maintained. Considering the complex character
of Western Processing water, these processes would not be
applicable.
EXAMPLE TREATMENT SYSTEM
As previously discussed, there is insufficient information
at this time to size a treatment system with any degree of
certainty that the system will meet the required removal
efficiencies. To illustrate the cost of an example treatment
system and level of treatment that might be required, the
following major assumptions were made:
1. Groundwater flow rate to the system will be 100 gpm,
24 hours a day, 365 days a year.
G-19
-------
2. The treated groundwater will be discharged to Metro.
3. There are no complexing agents in the wastewater that
would reduce the efficiency of heavy metals precipitation.
4. Hydrogen peroxide dose is assumed to be two times the
stoichiometric dose required to oxidize phenol to carbon
dioxide and water. (NOTE: This could be low by several
orders of magnitude if high levels of TIC's appear in
the groundwater.)
5. Lime dose is assumed to be two times the stoichiometric
dose required to precipitate the known heavy metals in
the groundwater.
6. Sludge quantities are assumed to be two times the
stoichiometric reactions with known heavy metals.
7. Activated carbon dose is assumed to be 10 pounds of
carbon per 1,000 gallons of water.
8. The predicted site average groundwater quality presented
in Table G-4 is an accurate assessment of the variabil-
ity of groundwater composition with time.
Bench- or pilot-scale testing is essential to confirming
these assumptions.
Using these assumptions, an example conceptual groundwater
treatment system was developed. The treatment units were
selected and sized using the onsite average groundwater
contaminant concentrations shown in Tables F-2 and F-3
(Appendix F) and the effluent limitations for discharge to
the Metro sanitary sewer system shown in Table G-2. There
are likely to be other process configurations that could
achieve similar effluent quality and that could even be more
cost effective than this example.
A process schematic for the example treatment configuration
is illustrated in Figure G-l. The groundwater will be
treated for organics and heavy metals removal using a com-
bination of four unit processes:
o Air stripping for volatile organics removal
o Lime precipitation for heavy metals removal, fol-
lowed by clarification and filtration
o Chemical oxidation of organics using hydrogen
peroxide
o Granular activated carbon adsorption for additional
organics removal
G-20
-------
Ground water
From Wells
Air-
Air Stripping
(Volatile Organics
Removal)
Lime
Polymer
1 Ferric Sulphate
I
tn
to
Surge Tank
Filter
^^ ./r | — Precoat
__ „ mi .. , , _.,.. ^^ir^ 1 /"^^™~^" Sludge to
L Rapid Mix Flocculation Uantier | 1 I Disposal
_ ? Vacuum Filter
H2S04 H202
1 1
\ \ \ \
\_ ^ \ Effluent Discharge
M pH Adjustment Oxidation
(Non-volatile Granular
Urganics Activated
s: Removal) Carbon
rocess configuration shown is based on present (Organics
vledge of groundwater composition. Pilot Removal)
tests will be required to verify process selection.
It is possible that additional (or fewer) processes
will be required.
2. Sequence of processes is subject to variation
based on outcome of pilot tests.
FIGURE G-1
GROUNDWATER TREATMENT
PROCESS FLOW CHART
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ORGANICS REMOVAL
Removal of organics is required to comply with the total
toxic organics pretreatment criterion. This criterion re-
sults from USEPA's categorical determination of industries'
ability to meet such a specification. The complexity and
strength of Western Processing organics may render compliance
with this limitation difficult even with the best of demon-
strated treatment processes. Treatability test work is nec-
essary to determine whether this pretreatment criterion is
technically feasible.
Applicability of the total toxic organics criterion to West-
ern Processing groundwater may need to be evaluated further.
USEPA regulations specify that the intended manner for in-
dustry compliance with this criterion is through best manage-
ment practices rather than end-of-pipe treatment technology -
However, best management practices for total toxic organics
are not applicable because the extracted groundwater to be
treated contains contaminants that have been transported
from generators' facilities, deposited at the site, and re-
leased to the environment.
Air stripping has been selected for the removal of volatile
organic contaminants. It is a reliable method for removing
volatile organics from contaminated water and has been used
at a number of hazardous waste sites to clean up contaminated
groundwater. The air-stripping tower was sized for a vola-
tile organics removal efficiency of approximately 99.5 per-
cent. It has been assumed that the resulting vapor emissions
would be very dilute and will meet air quality standards on
both a concentration and a mass basis. No gas-phase scrub-
bing equipment was included in this design because other
stripping towers have been installed in the local area with-
out gas treatment. However, this assumption needs to be
confirmed with the local regulatory agencies.
Chemical oxidation with hydrogen peroxide is used to oxidize
nonvolatile organics such as phenol. Chemical oxidation has
the advantages of low capital cost and easy operation and
can be adjusted to handle fluctuating organic loadings. In
fact, it is possible that hydrogen peroxide chemical oxida-
tion may be discontinued after several years due to lowered
organic concentrations (especially phenol) in the ground-
water. However, hydrogen peroxide will not selectively oxi-
dize toxic organics. Reactions with other organic compounds
may also consume peroxide, increasing dosage requirements.
Granular activated carbon adsorption is included in the
treatment process as a polishing step to remove residual
organic contaminants still remaining after air stripping and
chemical oxidation. Adsorption of organics on activated
carbon has been used extensively in similar applications and
G-22
-------
the technology is well established. It may be possible that
adequate total toxic organics removal can be achieved by
activated carbon absorption without being preceded by chemical
oxidation using hydrogen peroxide. However, optimization
cannot be made until testing is conducted on actual ground-
water samples.
INORGANICS REMOVAL
The average cyanide concentration is less than the Metro
effluent limitation of 2 mg/L and therefore separate cyanide
removal processes have not been included in the treatment
configuration. There are apparently no boron effluent
standards for discharge to Metro and therefore specific boron
removal processes have not been included. If the groundwater
boron concentration is subsequently found to be unacceptable,
an additional boron removal process such as selective ion
exchange would be required.
Heavy metals will be removed using a lime precipitation,
clarification, and filtration process. Most metal hydroxides
are insoluble at elevated pH levels and in this process,
lime is added to raise the pH level to between 9 and 11 to
precipitate metal hydroxides. The metals hydroxides are
settled in a gravity clarifier and removed as sludge. A
vacuum filter has been provided to dewater lime sludge, which
can be trucked to landfill disposal. Heavy metals removal
by lime precipitation is a proven method with low capital
and moderate operating costs. In addition, the process can
be operated on a continuous basis. Effluent from the lime
precipitation is filtered prior to further treatment. pH
adjustment may be required prior to hydrogen peroxide addi-
tion and/or activated carbon treatment, but would not normally
be required to meet Metro's effluent pH range of 5.5 to 12.5.
SIZING ESTIMATE
Table G-7 shows preliminary equipment sizes for the 100-gpm
example groundwater treatment system. This information was
used to develop capital and operating costs presented in
Chapter 6 under the specific alternatives that employ ground-
water treatment at a 100-gpm flow rate (Alternatives 2 and 5).
For the 85-gpm system used in Alternative 3, the estimated
capital costs would be approximately 90 percent of those
used for a 100-gpm system.
G-23
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Equipment
Table G-7
EXAMPLE SIZING ESTIMATE
100 GPM EXAMPLE GROUNDWATER
TREATMENT SYSTEM
Example
Quantity Units Dimensions
Air Stripping
Pumps
Fans
Towers
Precipitation
Rapid Mix
Flocculation
Clarifier
Filtration
Filters
Surge Tank
Backwash Pump
Polisher Feed Pump
pH Adjustment
Mix Tank
Equalization Tank
Sludge Dewatering Filter
Lime Storage Bin
Ferric Sulfate Handling
Sulfuric Acid Handling
Polymer Storage
Sludge Storage
Control Building
Peroxide Contact Tank
Hydrogen Peroxide Feed
System
Activated Carbon Bed
2
2
1
2
2
2
2
1
2
2
1
1
1
4
6,000
1
Example
Sizing Criteria"
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
Each
sq ft
Each
Each
Each
8'D x 26'H
4'D x 4'6"H
7.5'D x 8'H
20'D x 10'H
6' x 8'
14'D x 14'H
1.5 hp, 100 gpm @50'TDH
5 hp, 2,700 cfm @8"
16" packing depth
3 min. detention
20 min. detention
460 gpd/sq ft
2 gpm/sq ft
2 hrs, 30 min detention
750 gpm @60'TDH, 20 hp
100 gpm @40'TDH, 2 hp
8'D x 10'H 30 min. detention
14'D x 14'H 150 min. detention
1,950 Ib/hr (wet
sludge 1.5%) vacuum
filter
10'D x 16'H 900 Ib/day, 27 t
storage
25 Ib/day, Drums
negligible amount
5 Ib/day
7.5'D x 8'H 1,350 Ib/day dry 6 t
storage
60' x 100'
7.5'D x 8'H 20 min detention
10.5'D x 12'H 1,517 Ib/day
Storage Tank 1 week storage when
down 1 truck
7.5' x 12' Contact time 15 min.
Loading: 2.3 gpm/sq ft
Bed depth: 5 ft
atJsed for example sizing purposes only. This information should not be used for
process design.
D = diameter.
H = height.
G-24
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