Superfund Record of Decision: National Zinc Corp, OU 2, Bartlesville, OK (10/2/1997)


EPA  Superfund
       Record of Decision:
       National Zinc Corp, OU 2
       Bartlesville, OK
       10/2/1997
                                 PB97-964202
                                 EPA/541/R-97/119
                                 January 1998

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OKLAHOMA DEPARTMENT OF ENVIRONMENTAL
QUALITY
RECORD OF DECISION
FOR OPERABLE UNIT TWO OF
THE NATIONAL ZINC SITE
SITE NAME AND LOCATION

National Zinc Site
Bartlesvilie/ Oklahoma
and portions of Washington and Osage Counties, Oklahoma

STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected remedial action for
the second operable unit of the National Zinc Site, in Bartles-
ville, Oklahoma, developed in accordance with Comprehensive Envi-
ronmental Response, Compensation, and Liability Act (CERCLA) as
amended by Superfund Amendments and Reauthorization Act (SARA) and,
to the extent practicable, the National Oil and Hazardous Sub-
stances Pollution Contingency Plan (NCP). This decision is based
on the administrative record for the site.
• ';
ASSESSMENT OF THE SITE

Actual or threatened releases of hazardous substances from this
site, if not addressed by implementing the response action selected
in this Record of Decision (ROD), may present an imminent and
substantial endangermen.t to public health, welfare, or the environ-
ment .

DESCRIPTION OF THE REMEDY

This operable unit is the second of two for the site. The first
operable unit addresses the portions of the site that are most
likely to impact human health. The function of the first operable
unit is to reduce the risks to human health associated with expo-
sure to the contaminated materials. The ROD for Operable Unit One
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was written on December 13, 1994, and is being implemented at
this time. While the Operable Unit One remedy does address the
principle threats at the Site, the Second Operable Unit will
involve continued study and possible remediation of the portions of
the site that may pose undue risks to environmental receptors. The
second operable unit will also address any issues involving con-
tamination of ground water since it poses a potential ecological
threat. Ground water in the vicinity of the site is not used for
public or private drinking water supply but does discharge into
surface water in certain areas.

The major components of the selected remedy are as follows:

This ROD describes the remedial action selected for addressing
elevated metals concentrations in surface water and sediments at
Operable Unit 2 (OU2) of the National Zinc Site (the Site) in
Bartlesville, Oklahoma. The selected remedy is removal of con-
taminated sediment and offsite disposal for the impacted streams
and tributaries. Clean fill will be imported to replace the
excavated material in the lower reach of the North Tributary.
This remedy will allow the excavated sediment (treated as needed)
to be transported to an approved offsite disposal facility.
Additionally, the natural recovery option will be used for Eliza
Creek. During the remedial design, additional information will
be gathered to designate the actual areas to be removed. If the
destruction of the stream habitat will be too great in some
areas, then DEQ may choose to limit removal in sensitive portions
of the lower reach of the North Tributary. DEQ's goal is to
maximize removal of contaminated sediments and to minimize damage
to the ecosystem as much as possible.

AGRICULTURAL

Sampling of the agricultural areas will be done during the
remedial design. With this information, a site-specific agricul-
tural remedial action workplan shall be prepared and submitted
to the ODEQ.
STATUTORY DETERMINATIONS

The selected remedy is protective of human health and the environ-
ment, complies with Federal and State requirements that are legally
applicable or relevant and appropriate to the remedial action, and
is cost-effective. This remedy utilizes permanent solutions and
alternative treatment technologies to the maximum extent practica-
ble for this site. However, because treatment of the principal
threats of the site was not found to be practicable, this remedy
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does not satisfy the statutory preference for treatment as a
principle element of the remedy.

Because the remedy will result in hazardous substances remaining
on-site above ecologically based levels, a review will be conducted
five years after the commencement of remedial action to ensure that
the remedy continues to provide adequate protection of human health
and the environment.
Mark S.Coleman, Executive Director DATE
Oklahoma Department of Environmental Quality
•••a
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HIGHLIGHTS OF THE SELECTED REMEDY
The site is separated into operable units. This Record of
Decision is for Operable Unit Two which deals with ecologi-
cal concerns.
Remediation levels are being established for two different
land uses. These land uses are ecological areas and agri-
cultural areas.

Remediation Levels (mg/kg)
Ecological Agricultural

Lead 692 5000
Cadmium 100 305
Selenium 29.2 NA
Zinc 12,000 NA
Arsenic NA 200

The remedy selected for the ecological areas of the im-
pacted streams and tributaries is removal of the contami-
nated sediment and offsite disposal. Additionally, the
natural recovery will be used for Eliza Creek. Sampling of
the agricultural areas will be done during the remedial de-
sign. With this information, a site-specific agricultural
remedial action workplan will be prepared and submitted to
the ODEQ. More detail on these remedies will be provided
in the upcoming Remedial Design.
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THE DECISION SUMMARY
SITE LOCATION AND DESCRIPTION

This Record of Decision (ROD) addresses the National Zinc Site
(the Site) in Bartlesville, Oklahoma, and portions of Washington
and Osage Counties in Oklahoma. The National Zinc facility was
located on the western edge of the City of Bartlesville. The
location of the former National Zinc facility coincides with the
current location of the Zinc Corporation of America (ZCA) facili-
ty (Figure 1). The Site consists of those areas that have
concentrations of lead/ cadmium/ arsenic, selenium, and zinc in
soil and/or sediment, which exceed the remediation levels estab-
lished in this ROD, within approximately a 3-mile radius of the
ZCA facility. The ZCA facility is not a subject of this ROD or
of the subsequent remedial action; it is being addressed under
the authority of the Resource Conservation and Recovery Act of
1976 (RCRA), as amended. The term Site, as used in this ROD,
includes only areas beyond the boundary of the ZCA facility. The
former Somex facility location is not considered part of the ZCA
facility and is, therefore, part of the Site.

The Site covers a large area and is composed of a mixture of
properties used for residential, commercial, industrial, recre-
ational, and agricultural purposes. There are also some undevel-
oped lands which serve as wildlife habitat. The ZCA-facility is
now bounded to the west, northwest, and south by industrial and
commercial properties. Further to the west and south land uses
are primarily rural.-and agricultural. Residential properties
border the ZCA facility to the north, northeast, east, and south-
east. T\e central, eastern, and northern portions of the Site
are primarily urban. The main commercial district in the area is
in the center of Bartlesville approximately 1.5 miles to the east
of the ZCA facility. The population of Bartlesville is approxi-
mately 35,000. The City is essentially bisected from north to
south by the Caney River. Portions of the site lie within the
flood plain of the Caney River.

HISTORY AND ENFORCEMENT ACTIVITIES

There has been a long and complex history of metal processing
operations at the location of the present ZCA facility. In ap-
proximately 1907, three horizontal retort zinc smelters commenced
operation at this location. Two of the smelters appear to have
ceased operations in the 1920s. In 1976, the remaining horizon-
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tal retort zinc smelter was converted to an electrolytic zinc
refinery, which is not currently operating. During the time the
horizontal retorts were in operation, metals contained in the
airborne emissions from the smelter were deposited over much of
the area of Bartlesville which lies west of the Caney River.

The Site has been the subject of various prior studies and
investigations. These investigations revealed elevated con-
centrations of metals in the soil and sediment, including asso-
ciated surface waters, in portions of the area within approxi-
mately a three-mile radius surrounding the ZCA facility. The
metals include lead, cadmium, arsenic, and zinc. Soil sampling
showed that elevated concentrations of these metals were typical-
ly found in the uppermost few rnches of soil.

Historical sources of metals at the National Zinc site included
ore concentrates delivered to the facility by railcar, dust from
the transport and storage of ore concentrates and solid waste
materials at the facility, metals emissions from roasting and
smelting processes, airborne particulates from smelting and
sintering processes, and various solid waste materials (e.g.,
retort and sinter residues, slag, crushed retorts, and condenser
sands). Current potential sources of metals at the ZCA facility
are being addressed by EPA pursuant to RCRA under a Consent Order
with ZCA, the current owner and operator of the facility.

On May 10, 1993, the United States Environmental Protection
Agency (EPA) proposed that the Site be placed on the National
Priorities List (NPL). Subsequently, a memorandum of understand-
ing (MOU) was signed between EPA and DEQ to conduct a national
pilot project to complete a Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) quality investigation
and remediation of the Site under state authority. EPA agreed to
not make a final determination to list the Site on the NPL as
long as the pilot project proceeds in a timely manner and
achieves CERCLA quality results.

A remedial investigation and feasibility study (RI/FS) was
conducted by PTI Environmental Services (PTI) on behalf of the
potentially responsible parties (PRPs), Cyprus Amax Minerals Com-
pany, Salomon Inc, and the City of Bartlesville. The RI/FS was
conducted pursuant to a Consent Agreement and Final Order for
Remedial Investigation, Feasibility Study, and Remedial Design
(Case No. EH 94 106) entered into with DEQ. DEQ is responsible
for the oversight of the RI/FS and remedy selection for the Site,
under the State Pilot Project being conducted in conjunction with
the EPA.
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In addition to the investigations conducted at the Site, removal
actions for OU1 have been and are currently being conducted to
address areas that have elevated concentrations of metals in
soil. In 1992, EPA evaluated soils at 54 high access areas and
the decision was made to take actions on soils at 25 of those
locations. In 1993, soils in 22 residential yards were evaluated
by EPA and the decision was made to remediate soils at 10 of
those residences. The high-access areas include places where
children congregate such as schools, day care and family care
centers, and parks. In 1994, Mintech, Inc., acting on behalf of
Cyprus Amax Minerals Company, Salomon Inc, and the City of
Bartlesville, began a second round of removal actions for certain
residential yards under a Unilateral Administrative Order from
EPA. This second round of removal actions consists of removing
soil from yards where at least one soil sample contains elevated
concentrations of metals (i.e., greater than 1,500 mg/kg lead or
90 mg/kg cadmium) and replacing it with clean soil and sod.

In 1995, the third round of removal actions began under the same
Unilateral Administrative Order that was in effect in 1994. On
August 7, 1995, a Consent Agreement and Final Order between ODEQ
and Cyprus Amax Minerals Company and the City of Bartlesville was
issued with removal of contaminated soils continuing. The
remedial action levels for Operable Unit One are 925 mg/kg for
lead, 100 mg/kg for cadmium, and 60 mg/kg for arsenic. The
removal of soils is still ongoing at this time.

COMMUNITY PARTICIPATION

The involvement of local citizens in this project has been a
major goal of both DEQ and EPA. The scope and complexity of this
project necessitated more intensive efforts to involve the
community than is-typical of most projects. In 1992, DEQ estab-
lished a steering committee of local representatives which
attempted to include all potentially affected stakeholders in the
community of Bartlesville. The steering committee serves as a
mechanism to voice local concerns directly to the regulatory
agencies throughout the project. Public meetings are also held
in the evening following steering committee meetings and the
general public has been provided information on the project in
smaller portions and in a more timely manner than is typical of
most projects. DEQ and EPA have jointly participated in numerous
meetings with the public throughout the project. Much of the
information that is included in the remedial investigation and
feasibility study reports was released and discussed with the
public several months before the completion of the final docu-
ments .
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The Remedial Investigation and Feasibility Study report was
released in spring of 1996. The proposed plan was released to
the public for review and comment on May 2, 1996. The adminis-
trative record and copies of these two documents are available at
two public repositories in the City of Bartlesville, the Bartles-
ville Public Library and the Bartlesville Chamber of Commerce.
These documents are also available for public review at the DEQ
central office. The potentially responsible parties (PRPs) have
also established a public information office staffed by a local
representative to assist citizens in obtaining information and
answering questions regarding the site. The notice of availabil-
ity was published in the Bartlesville Examiner-Enterprise. A
public comment period was held from May 2, 1996, to June 2, 1996.
A public meeting, held on May 2, 1996, presented the proposed
plan to the public and invited comment. Responses to comments
received are included as part of this ROD in the Responsiveness
Summary.

SCOPE AND ROLE OF OPERABLE UNIT WITHIN SITE STRATEGY

Due to the complexity of the site and the desire to expedite
cleanup in residential areas, the site has been divided into two
operable units. They are:

Operable Unit 1 - Residential, Commercial, and Industrial areas;
Operable Unit 2 - Ecologically Sensitive and Agricultural areas

This ROD details the remedy selected for Operable Unit 2.
Operable Unit 1 was addressed in the Record of Decision dated
December 13, 1996. An evaluation of the use of groundwater in
the vicinity of the site did not identify any active public or
private water wells. No viable groundwater resources have been
identified beneath the site. Therefore, ground water issues will
be evaluated and addressed as part of Operable Unit 2. Groundwa-
ter is not used as a water supply and only potentially impacts
environmental receptors when it discharges to surface waters.

SUMMARY OF SITE CHARACTERISTICS

The remedial investigation revealed that sediment contamination
by lead, cadmium, selenium, and zinc is present, in elevated
concentrations, over a relatively widespread area. Airborne
emissions from historical smelting operations and associated
activities appear to be a significant mechanism of dispersal of
the contaminants across the site. In addition, spillage and wind
transport of ore concentrates from rail cars may have also
contributed to elevated metals at the site. It is also likely
that solid waste materials from the smelters were physically
moved to areas within the site boundaries for use as fill or for

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other purposes. Lead, cadmium, and arsenic may also have other
non-smelter related sources in a typical urban and rural envi-
ronment. The concentrations of metals are not uniform across the
site and some areas within the site boundaries are not signifi-
cantly impacted.

Soil, surface water, and sediments are considered media of
potential concern for the Ecological Risk Assessment for Operable
Unit 2. Shallow groundwater is also a medium of potential
concern for Operable Unit 2 because metals may be transported
from the ZCA facility to the surface water south of the facility.
Metals concentrations measured in air have not exceeded regulato-
ry limits. Groundwater at the Site is not used for drinking
water because aquifers under the Site yield only small amounts of
poor quality water due to natural geologic conditions and histor-
ical oil production activities.

TABLE 1.
REMEDIATION LEVELS FOR PROTECTION OF ECOLOGICAL AND AGRICULTURAL AREAS

Arsenic
Cadmium
Lead
Selenium
Zinc
Ecological
NA
100
692
29.2
12,000
Agricultural
200
305
5000
NA
NA
Note: Concentration measurements in mg/kg.
NA not applicable
Areas and volumes o-f •potential concern were estimated for soil
based on preliminary remediation goals for the ecological areas.
The purpose of this estimation was only to develop cost estimates
and to allow comparisons among remedial alternatives. The actual
areas to be remediated will be defined during the remedial design
phase based on data available at that time including the scree-
ning data from the current removal action.

SUMMARY OF SITE RISKS TO HUMAN HEALTH
DESCRIPTION OF ALTERNATIVES
In the Focused Feasibility Study (FFS), several methods for
remediation of the Site were described and evaluated. A summary
of the remedial action alternatives is presented here. A list of
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the alternatives is shown in Table 2. The FFS report contains a
more detailed description of the alternatives.

Alternatives include Sd-1, no action; Sd-2, institutional con-
trols; Sd-3, partial removal, stabilization, and offsite dis-
posal, and partial natural recovery; Sd-4, partial removal,
stabilization, and offsite disposal, and partial rechanneliza-
tion; Sd-5a, removal, stabilization, and offsite disposal; and
Sd-5b, removal, stabilization, and onsite disposal. Alternatives
Sd-2 through Sd-5b assume that any required source control
activities at the ZCA facility will be implemented in accordance
with RCRA Permit No. OKD000829440 issued July 14, 1995. Any
required corrective measures would commence at approximately the
end of 1997. Alternatives Sd-2 through Sd-5b also assume that
source control measures at adjacent industrial areas, if re-
quired, will be implemented pursuant to the Consent Agreement and
Final Order ;CAFO) for Remedial Action between DEQ, Cyprus Amax
Minerals Company, and the City of Bartlesville entered into on or
about August 7, 1995. Remediation of sediments (and surface
water, if necessary) will be deferred until source control
activities are implemented. Subsequent references to source
control activities refer to the source control activities at the
ZCA facility and adjacent industrial areas.

Alternative Sd-1: No Action

The no-action alternative is required to be considered by EPA as
a baseline to which all other alternatives must be compared. No
further efforts would be conducted at the Site under the no
action alternative. Monitoring would not be included in this
alternative. Some natural recovery could occur by sediment
transport and deposition processes.
• ^
Alternative Sd-2: Institutional Controls

Institutional controls would include deed restrictions for
properties where sediment with elevated chemicals of potential
concern (CoPCs) is left in place, as appropriate, to restrict the
future use of the property. This alternative assumes that source
control activities will be implemented. In addition, ongoing
monitoring of sediment and surface water would be conducted.
Monitoring would be conducted in the same areas annually for 3
years and, if needed, biannually for up to 7 more years, and in
other areas would be conducted biannually for 10 years. Some
natural recovery could occur by sediment transport and deposition
processes.
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Common Components of Active Soil Remediation Alternatives

Components that are common to the active remediation alternatives
(those alternatives involving removal of sediment as a component
of the alternative) are discussed here as a group in order to
limit redundancy in the subsequent discussion of the individual
alternatives. These components are:

• Source control activities will be implemented.
Remediation of sediments (and surface water, if nec-
essary) will be deferred until source control ac-
tivities are implemented.

• The construction season would be during the dry sea-
son, which is approximately from the middle of June
to the middle of October.

• Work would be conducted using an appropriate level
(Level D) of personal protective equipment (PPE)
based on previous experience with the removal ac-
tions conducted at the Site. The level of PPE may
be revised during the course of remediation based on
the health and safety monitoring conducted at the
Site.

• Access agreement(s) for sediment sampling and reme-
diation would be requested from the property
owner(s). Remediation of a tributary segment would
begin only after all access agreement(s) have been
obtained for that segment.

• Photographic records would be made prior to and upon
completion of remediation activities.
' • "•
• During remediation activ cies, fugitive dust from
the work areas (e.g., haul roads) would be con-
trolled through a water spray by a tank truck or
comparable equipment.

» Equipment would be decontaminated prior to being re-
leased from the Site. It. is anticipated that decon-
tamination would consist of scraping the residual
sediment off the equipment and rinsing it with clean
water. Decontamination residues that are generated
would be incorporated into the removed or contained
sediment, where possible.

• After source control activities are implemented and
sediment is removed from the upper reaches of the
North Tributary, surface water and sediment would be

11
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monitored to determine whether the RAOs are
achieved. If RAOs are not achieved, additional
measures would be taken, which may include source
identification and construction of a passive metals
treatment system most likely in the upper reaches of
the North Tributary to control potential ongoing
sources of dissolved metals (particularly cadmium)
in surface water. The tributary channels would be
widened to form flow-equalization ponds. The outlet
of the ponds would be directed into channels con-
taining adsorptive media (e.g., peat, activated car-
bon, and/or pea gravel coated with hydrous-ferric-
oxide- (HFO-) to attenuate the concentrations of
cadmium, lead, and zinc in the surface water.

In addition, the following components are common to Alternatives
Sd-4, Sd-5a, and . i-5b.

• Restoration would be conducted in the lower reach of
the North Tributary in disturbed areas following
sediment removal; it would not be conducted in the
upper reaches of the North Tributary. Restoration
would include supplying and placing an equivalent
volume of large woody debris as in the original
channel. The toes of near-vertical banks would be
armored, as required, to provide protection against
erosion during floods. Banks that are steeper than
2:1 (2 horizontal:! vertical) may require erosion
control such as blankets or mulch to allow estab-
lishment of vegetation. Restored floodplain areas
would be revegetated with an appropriate native
grass/forb seed mixture. Noxious or invasive weed
species in the floodplain upstream of the restored
section may need to be eradicated for the revegeta-
tion effort to be successful. Willow sprigs may be
planted on the stream banks, if appropriate.

• Restoration design would include mapping and survey-
ing the existing stream channel (the lower reach) to
determine characteristics and dimensions of the re-
stored stream, mimicking the existing channel.
Alternative Sd-3: Partial Removal, Stabilization, and Partial Natural
Recovery

This alternative would include a combination of technologies to
take into account the site-specific conditions of the different
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segments of the North Tributary. The sediment in the upper
reaches of the North Tributary would be removed, stabilized to
pass the Toxicity Characteristic Leaching Procedure (TCLP) test
as needed/ and disposed of offsite as in OU1 or at the ZCA
facility, subject to ZCA and any required regulatory approval.
After this sediment is removed, the lower reach would recover
with the transport and deposition of clean sediment. Figure 2
shows the locations of the areas considered for sediment removal
or natural recovery as defined under the Feasibility Study
Report. Actual areas for remediation and other areas will be
further refined during remedial design.

Prior to sediment removal, the stream flow would be diverted as
required and the sediments would then be excavated; It may be
necessary to further evaluate potential stream dewatering and
flow diversion options during remedial design. The sediment
would be removed using a Bobcat* loader, backhoe, or mechanical
dredge. The backhoe or mechanical dredge would also be able to
remove debris, as necessary, in order to gain access to the
sediments. Sediment resuspension would be controlled by divert-
ing the stream flow (if any) around the area being excavated. In
addition, silt curtains may be used further downstream to reduce
the transport of residual suspended solids, if any.

Mechanical excavation would remove the sediment at near in situ
densities (U.S. EPA 1993). The sediments would be hauled in end-
dump trucks equipped with watertight tailgate seals and tarps to
the OU1 temporary storage area. For this evaluation, it was
assumed that sediment dewatering and particle size reduction
would not be-conducted. Enhanced dewatering techniques would not
be required. The sediments would be stabilized using lime,
cement, fly ash, or other stabilization agents to pass the TCLP
(as necessary), or mixed with dry soil. The pore water in the
sediments would be -incorporated into th« stabilization process or
the dry soil. The specific stabilization agent, application
rate, and curing time would be determined by treatability studies
during remedial design. For the purposes of the FFS, it is
assumed that stabilization would be needed for 20 percent of the
sediments in the upper reaches of the North Tributary.

The sediment would be transported to an appropriate non-hazardous
waste disposal site which would include either the ZCA facility,
subject to ZCA and any required regulatory approval, or the OU1
non-hazardous waste landfill. If disposed of at the ZCA facil-
ity, the sediment would be disposed of in a manner that is
compatible with closure activities at the facility. The sediment
would be transported in trucks using appropriate preventive
measures. The trucks would be covered with tarps.
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With removal of contaminated sediment from the upper reaches of
the North Tributary (an erosional segment of the stream), sedi-
ment deposited in the future in the lower'reach (the depositional
segment of the stream) will have reduced concentrations of
metals. This clean sediment will, in time, provide a natural
cover of the contaminated sediment now present in the lower
reach. This will limit exposure of benthic organisms in the
lower reach to site metals without disrupting the favorable
habitat that already exists in the lower reach. Studies of site-
specific partioning coefficient or Kds have indicated that site
sediments have a high adsorption capacity. Because the contami-
nated sediment in the upper reaches will be removed, it is
expected that dissolved site metals will not be present at
concentrations high enough to result in significant adsorption to
sediments in the stream.. If dissolved site metals are still
present at elevated concentrations, then additional measures
would be taken, which may include construction of a passive
metals treatment system in t. 2 upper.reaches of the North Tribu-
tary. There will likely be a slow net reduction in metals
concentrations in the sediments currently present in the lower
reaches due to a slow desorption of metals from these sediments.

Ongoing monitoring of the sediment and surface water would be
conducted after completion of remediation to demonstrate that the
RAOs and final remediation levels have been met. (Monitoring
would be conducted in the same areas annually for three years
and, if needed, biannually for up to seven years, and in other
areas would be conducted biannually for 10 years.) Monitoring
would evaluate channel stability and reduction of metals concen-
trations in surficial sediment (the biologically active zone) and
surface water.

Alternative Sd-4: Partial removal, Stabilization, and Offsite disposal
and Partial tributary rechannelization, and Capping the existing
channel with soil

Like the previous alternative, this alternative would also
include a combination of technologies to take into account the
site-specific conditions of the different segments of the North
Tributary. The sediment in the upper reaches of the North
Tributary would be removed, stabilized to pass the TCLP test as
needed, and disposed of offsite or at the ZCA facility, subject
to ZCA and any required regulatory approval. Remediation of the
lower reach of the North Tributary would involve creating a new
tributary channel and using the excavated soil to fill the
existing tributary channel. The new channel would be constructed
adjacent to the existing channel as shown in Figure 3.
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Removal of the sediment in the upper reaches of the North Tribu-
tary would be conducted in the same manner as discussed in the
preceding alternative. After removal of the sediment, the lower
reach would be rechannelized. Prior to excavation for rechan-
nelization, the stream flow would be temporarily diverted as
required to allow the remediation activities to be conducted. One
stream bank would be excavated down to the hard bottom using
conventional excavation equipment to create a new tributary
channel (small equipment such as a Bobcat* loader may be neces-
sary in limited-access areas). Alternate stream banks may be
excavated, as appropriate/ to avoid excavating around trees. The
excavated material would be used to cap the existing channel
sediments and floodplain soils as shown in Figure 3. A 3-in. cap
of topsoil would be placed over the capped area and restoration
activities would be conducted. The cap would be armored as
required to provide protection against erosion. Turbidity
controls and long-term monitoring would be the same as in the
preceding alternative.
Alternative Sd-5a: Removal, Stabilization, and Offsite Disposal

This alternative would include the same removal and disposal
components as Alternative Sd-3 (Partial Removal and Partial
Natural Recovery), except that removal would occur throughout the
entire tributary segments targeted for remediation (i.e., the
upper reaches and the lower reach of the North Tributary). A
cross section of the lower reach of the North Tributary for
sediment removal is shown in Figure 4. Clean fill would be
imported to replace the excavated material in the lower reach of
the North Tributary. The imported fill would be similar to the
excavated sediment. .sFor the purposes of the FFS, it is assumed
that 20 percent of t&e fill would be topsoil to reconstruct the
floodplain areas. The remaining portion of the fill would be
sand. After placement of the fill, the stream restoration
activities would be conducted in the lower reaches of the tribu-
taries.
Alternative Sd-5b: Removal, Stabilization, and Onsite Disposal

This alternative would be the same as Alternative Sd-5a (Removal
and Offsite Disposal) except that the excavated sediment (treated
as needed) would be transported to the ZCA facility for disposal,
subject to ZCA and any required regulatory approval. The sedi-
ment would be disposed of in a manner that is compatible with
closure activities at the facility.

15
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DEQ's Preferred Alternative

Data collected during FFS field sampling and during previous
investigations at the Site indicate that sediments in two main
areas of the North Tributary have metals concentrations that
exceed PRGs: the two upper reaches located near the ZCA facil-
ity, which are erosional areas not considered to be important
habitat areas, and the mainstream of the North Tributary from
sampling station RD5 to the confluence with Eliza Creek (the
"lower reach"), which is a depositional area with generally
favorable habitat. The middle section of the North Tributary,
from the junction of the upper reaches down to KD4, is not a
depositional area and metals concentrations in this section do
not exceed PRGs. Elevated metals concentrations in surface water
have been observed coincident with elevated metals levels in
sediment.

The recommended remedial alternative lor the Site includes parts
of Alternative Sd-3 Partial removal, Stabilization, and Offsite
Disposal, and Partial Natural Recovery and Sd-5a, Removal,
Stabilization, and Offsite Disposal. This alternative would
include the same removal and disposal components as Alternative
Sd-3 (Partial Removal and, Stabilization, and Offsite Disposal,
and Partial Natural Recovery), except that removal would occur
throughout the entire tributary segments targeted for remediation
(i.e., the upper reaches and the lower reach of the North Tribu-
tary) . The upper and lower reaches are shown in Figure 6. Clean
fill.would be imported to replace the excavated material in the
lower reach of the North Tributary. The imported fill would be
similar to the excavated sediment. For the purposes of the FFS,
it is assumed that 20 percent of the fill would be topsoil to
reconstruct the floodplain areas. The remaining portion of the
fill would be sand. After placement of the fill, the stream
restoration activities would be conducted in the lower reaches of
the tributaries. This alternative would allow the excavated
sediment (treated as needed) to be transported to an approved
offsite disposal facility. Additionally, the natural recovery
option will be used 'for Eliza Creek. During the remedial design,
additional information will be gathered to designate the actual
areas to be removed. If the destruction of the stream habitat
will be too great in some areas, then DEQ may choose to limit
removal in sensitive portions of the lower reach of the North
Tributary. DEQ's goal is to maximize removal of contaminated
sediments and to minimize damage to the ecosystem.
16
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REMEDIAL ACTION OBJECTIVES AND RISK-BASED CONCENTRATIONS FOR
AGRICULTURAL AREAS

For agricultural areas, media of concern for protection of humans
is the soil. Remedial Action Objectives (RAOs) and Preliminary
Remediation Goals (PRGs) for soil were established using informa-
tion from the land application of sludge. RAOs are chemical- and
medium-specific goals for protecting human health and the envi-
ronment, and typically specify the exposure routes, receptors,
and risk levels of concern. RAOs provide the basis for deriving
risk-based concentrations (RBCs), which are specific contaminant
concentrations that are protective of human health and the
environment and comply with applicable or relevant and appropri-
ate requirements (ARARs).

The RAOs for agricultural soils are:

• Prevent plants grown for direct human consumption from uptak-
ing elevated concentrations of CoPCs that may be present in
the soils

• Prevent human ingestion of animals that have eaten plants
grown in the soil which may uptake elevated concentrations of
CoPCs that may be present in the soils

• Prevent the equipment operator from being exposed to dust from
soils with elevated concentrations of CoPCs while working the
ground

PRGs for soil were based upon risk-based concentrations for
metals in soil. These values were taken from the technical
support document for land application of sewage sludge prepared
by the Eastern Res.ea.rch Group for the U.S. Environmental Protec-
tion Agency (November 1992). The PRG values are:

• Cadmium— 305 mg/kg dry weight

• Lead— 5,000 mg'kg dry weight

• Arsenic— 200 mg/kg dry weight.

Sampling of the agricultural, areas by the potentially responsible
parties (PRPs) shall be conducted during the remedial design.
With this information, a site-specific agricultural remedial
action workplan shall be prepared and submitted by the PRPs to
the ODEQ.
17
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SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES

The alternatives in the feasibility study were evaluated based on
the criteria described in Table 3. The following is a summary of
the evaluation.

Overall Protection of Human Health and the Environment

Alternatives Sd-3, Sd-5a, and Sd-5b would all achieve approxi-
mately the same level of overall long-term protection of the
environment, but would differ significantly regarding their
short-term effects during remediation. Alternative Sd-3 would
rank the highest because it would be protective in the long term
and have minimal short-term effects on human health and the
environment because only the upper reaches of the. North Tributary
(essentially intermittent drainage ditches wi.;h little or no
aquatic habitat value) would be disturbed during remediation.
Alternatives Sd-5a and Sd-5b would also provide long-term protec-
tion. However, under those alternatives, some of the habitat in
the lower reach (mature trees along the riparian zone that
provide important bird habitat and aesthetic values) would be
destroyed during remediation and there would be a greater poten-
tial impact on Eliza Creek because of the location of the lower
reach (it flows directly into Eliza Creek), and the size of the
lower reach would make it more difficult to control during
remediation. Alternatives Sd-5a and Sd-5b would also have
greater short-term effects on the riparian area and upland fields
adjacent to the North Tributary and to the construction workers
and community during the removal and transport of the large
volume of sediment. Alternative Sd-4 could be protective in the
long term, but there is a greater degree of uncertainty associ-
ated with rechanneli.zation; it would require a significant amount
of maintenance to ensure the capped sediments are adequately
contained. . Alternative Sd-4 would also have the same short-term
detrimental effects on the lower reach as Alternatives Sd-5a and
Sd-5b. Alternatives Sd-1 and Sd-2 would not be protective of the
environment.

Compliance with ARARs

The active sediment alternatives (Alternatives Sd-3 through Sd-
5b) are essentially comparable for this criterion. Alternatives
Sd-4, Sd-5a, and Sd-5b may have a greater chance for short-term
exceedances of surface water quality standards during remedia-
tion. Institutional controls (Alternative Sd-2) may not comply
with ARARs. The no-action alternative (Alternative Sd-1) would
not comply with ARARs.

18
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Cost

The estimated costs for the alternatives are presented in Table
4. Alternatives Sd-1 and Sd-2 have the lowest estimated costs.
Of the active remediation alternatives (Alternatives Sd-3 through
Sd-5b), Alternative Sd-3 has the lowest estimated costs. Alter-
natives Sd-5a and Sd-5b are essentially comparable in estimated
costs. Alternative Sd-4 has the highest estimated costs.
TABLE 4.
COST OF ALTERNATIVES
Al ternatives
Sd-1 No Action
Sd-2 Institutional Controls
Sd-3 Partial Removal and Partial
Natural Recovery
Sd-4 Partial Removal and Partial
Rechannelization
Sd-5a Removal and Offsite Dis-
posal
Sd-5b Removal and Onsite Disposal
DEQ's Preferred Alternative
Cost($ Million)
0
0.06
2.3
3.3
2.8
2.7
2.8
Long-Term Effectiveness and Permanence

This evaluation criterion addresses the results of a remedial
action in terms of the risk remaining at the Site after the final
remediation levels have been met. Since the chemicals of poten-
tial concern are metals and they cannot be destroyed, permanence
of remedial alternatives must be judged in terms of the elimina-
tion of exposure to these compounds and/or altering their bio-
availability.

As discussed previously, Alternatives Sd-3, Sd-5a, and Sd-5b
would provide long-term protectiveness. Alternative Sd-4 could
be protective in the long term, but there is a greater degree of
uncertainty associated with rechannelization; it would require a
significant amount of maintenance to ensure the capped sediments
are adequately contained. Alternatives Sd-1 and Sd-2 would not
be protective of the environment. The DEQ's preferred alterna-
19
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tive will eliminate exposure to significantly elevated levels of
the chemicals of potential concern.

Short-Term Effectiveness

Alternative Sd-3 would have minimal impact on human health and
the environment because only the upper reaches of the North
Tributary would be disturbed during remediation. Under this
alternative there would be minimal if any impact on the lower
reach of the North Tributary and Eliza Creek, which both have
established habitats that support a variety of aquatic and
terrestrial organisms. The location of the upper reaches (close
to access roads) would minimize impacts on the fields adjacent to
the North Tributary. The small size of the channels in the upper
reaches would enable remediation to be conducted in a controlled
manner that would prevent the release of CoPCs to the downstream
segment. Alternatives Sd-4, Sd-5a, and Sd-5b would a.M destroy
some of the habitat in the lower reach during remedio-ion. The
habitat would eventually be restored through post-remediation
restoration efforts. Under those alternatives there would also
be a greater potential impact on Eliza Creek because of the
location of the lower reach (it flows directly into Eliza Creek)
and the size of the lower reach would make it more difficult to
.control during remediation (i.e., there would be a greater chance
of releases of CoPCs to Eliza Creek during remediation). Alter-
natives Sd-4, Sd-5a, and Sd-5b would also have greater short-term
effects on the riparian area and upland fields adjacent to the
North Tributary during construction of access roads and use of
heavy construction equipment along the banks of the North Tribu-
tary. The additional construction activities would present a
greater risk to construction workers. Under Alternatives Sd-5a
and Sd-5b, there would also be a greater impact on the community
during the removal and transport of the large volume of sediment.
Alternatives Sd-1 'arid Sd-2 would have short-term effects result-
ing from the continued exposure of aquatic organisms and trans-
port of CoPCs in the North Tributary.

Reduction of Toxicity, Mobility, and Volume Through Treatment

All of the active alternatives (Alternatives Sd-3 through Sd-5b)
would have comparable reductions in toxicity and mobility result-
ing from stabilization of. excavated sediment and treatment of the
surface water using a passive metals treatment system, if neces-
sary. Alternatives Sd-1 and Sd-2 would not result in any reduc-
tions of toxicity, mobility, or volume through treatment.
20
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Implementability

Of the active remediation alternatives (Alternatives Sd-3 through
Sd-5b), Alternative Sd-3 would be the easiest.to implement
because of the location of the upper reaches (close to access
roads) and the smaller channels would enable remediation to be
conducted in a controlled manner. Alternatives Sd-4, Sd-5a, and
Sd-5b would be more difficult to implement because the degree of
difficulty is compounded by the location of the lower reach (it
is farther from existing roads), the larger size of the streambed
including the higher flow rate, the larger volume of sediment
that would be remediated, and the greater chance that the sedi-
ment from the lower reach would need to be dewatered and the
effluent treated. In addition, Alternative Sd-4 would require
extensive ongoing maintenance to ensure that the sediments are
adequately contained. Restoration efforts would also need to be
implemented for the lower reach to re-establish the existing
aquatic habitat. Alternatives Sd-1 and Sd-2 would be imple-
mentable from a technical standpoint*
Community Acceptance

The acceptance of the preferred alternative and/or other alterna-
tives by the Bartlesville Community was evaluated through the
public participation process and comments received during the
formal public comment period. These comments are addressed in
this ROD in the Responsiveness Summary. None of the comments*
received indicated a preference for another alternative over
DEQ's preferred alternative.

State/Federal Acceptance

This is typically a criteria used in the Superfund process.
However, because the project is being led by a state agency,
federal acceptance has been evaluated in lieu of state accep-
tance. Federal acceptance has been evaluated based on any com-
ments received during the formal public comment period from EPA
or other federal agencies. The comments received are addressed
in the Responsiveness Summary of this ROD.
21
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THE SELECTED REMEDY

The selected remedy is DEQ's preferred alternative. DEQ's
preferred alternative is a combination of two of the other
alternatives discussed in the Feasibility Study. The preferred
alternative includes elements of Alternatives Sd-3 (Partial
Removal and Partial Natural Recovery)and Sd-5a (removal and
offsite disposal).

The recommended remedial alternative for the Site is Alternative
Sd-5a, Removal and Offsite Disposal. This alternative would
include the same removal and disposal components as Alternative
Sd-3 (Partial Removal and Partial Natural Recovery), except that
removal would occur throughout the entire tributary segments
targeted for remediation (i.e., the upper reaches and the lower
reach of the North Tributary). The upper and lower reaches are
shown in Figure 6. Clean fill would be imported to replace the
excavated material in the lower reach of the North Tributary.
The imported fill wo\ild be similar to the excavated sediment.
For the purposes of the FFS, it is assumed that 20 percent of the
fill would be topsoil to reconstruct the floodplain areas. The
remaining portion or the fill would be sand. After placement of
the fill, the stream restoration activities would be conducted in
the lower reaches of the tributaries.. This alternative would
allow the excavated sediment (treated as needed) to be trans-
ported to an approved offsite disposal facility. Additionally,
the natural recovery option will be used for Eliza Creek. During
the remedial design, additional information will be gathered to
designate the actual areas to be removed. If the destruction of
the stream habitat will be too great in some areas, then DEQ may
choose to limit removal in sensitive portions of the lower reach
of the North Tributary. DEQ's goal is to maximize removal of
contaminated sediments and to minimize damage to the ecosystem as
much as possible.

22
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REMEDIAL ACTION OBJECTIVES AND RISK-BASED CONCENTRATIONS FOR
AGRICULTURAL AREAS

The RAOs for agricultural soils are:

• Prevent plants grown for direct human consumption from uptak-
ing elevated concentrations of CoPCs that may be present in
the soils

• Prevent human ingestion of animals that have eaten plants
grown in the soil which may uptake elevated concentrations of
CoPCs that may be present in the soils

• Prevent the equipment operator from being exposed to dust from
soils with elevated concentrations of CoPCs while working the
ground

PRGs for soil were based upon risk-based concentrations for
metals in soil. These values were taken from the technical
support document foreland application of sewage sludge prepared
by the Eastern Rese'arch Group for the U.S. Environmental Protec-
tion Agency (November 1992). The PRG values are:

• Cadmium— 305 mg/kg dry weight

• Lead— 5,000 mg/kg dry weight

• Arsenic- 200 mg/kg dry weight.

Sampling of the agricultural areas will be done during the
remedial design. With this information, a site-specific agricul-
tural remedial action workplan will be prepared and submitted to
the ODEQ.
23
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STATUTORY DETERMINATIONS

Protection of Human Health and the Environment

The selected remedy for Operable Unit Two will be effective in
eliminating or reducing risks to public health. The selected
remedy will achieve these goals through a combination of the
removal of contaminated soils, the use of engineering controls,
the use of institutional controls, and where appropriate the
treatment of contaminated soils. The remediation levels that
will be used are sufficiently protective of human health and fall
within the range of such standards established at similar sites
across the Nation.

Any potential cross-media impacts that might occur as a result of
the implementation of the selected remedy can readily be con-
trolled through standard monitoring and engineering controls.
The selected remedy calls for air monitoring to be conducted
throughout construction activities and dust control measures to
be instituted when necessary. No unacceptable short-term risks
will be caused by the implementation of the selected remedy.
24
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Compliance with ARARs

The selected remedy will comply with the following ARARs.
CHEMICAL
SPECIFIC
ARARS
Standard/ Requirement,
Criteria or
Limitation

Federal
Citation
Application
Solid Waste Disposal Act
& Resource Conservation
and Recovery Act (RCRA)
40 CFR Part 261
Applicable. Some
of the soils that
will be removed
from the site
could exhibit the
characteristic of
toxicity. Any
soils that exhibit
this characteris-
tic will require
treatment.
Clean Air Act
National Ambient Air
Quality Standards
40 CFR Part 50
Relevant and
Appropriate during
construction
activities
State
Oklahoma Hazardous* Waste
Management Regulations
OAC 252:200
Applicable. Same
reason as above.
Oklahoma Environmental
Quality Code
27A Oklahoma
Statutes
Section 2-1-101
et seq.
Applicable. Soil
contamination is a
public nuisance.
Oklahoma Air Pollution
Control Regulations
OAC 252:100
Applicable if air
concentrations are
above the maximum
allowable increase
due to remedial
action.
25
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ACTION SPECIFIC
ARARS
Standard, Requirement,
Criteria, or Limitation
Citation
Application
Federal
Solid Waste Disposal
Act

RCRA Subtitle C
40 CFR Parts 261
264 & 265
Applicable.
Portions may be
relevant and
appropriate to
storage and treat-
ment of waste for
off-site shipment.
Occupational Safety and
Health Act (OSHA)
Regulations
29 CFR 1910
Applicable. It is
the responsibility
of employers
involved in activi-
ties on the site to
conform with the
requirements of
OSHA.
State
Oklahoma Environmental
Quality Code
27A Oklahoma
Statutes Section
2-1-101 et seq.
Applicable. Soil
contamination as a
public nuisance.
Oklahoma Hazardous
Waste Management Regu-
lations
OAC 252:200
See criteria for 40
CFR Parts 261, 264,
and 265
Oklahoma Air Pollution
Control Regulations
OAC 252:100
Applicable if
sufficient emis-
sions were gener-
ated as a result of
construction
activities.
Oklahoma Solid Waste
Management Regulations
OAC 252:500 & 510
Applicable to any
offsite disposal of
nonhazardous waste.
Relevant and
appropriate to any
possible onsite
disposal options.
26
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Cost-Effectiveness

The selected remedy is currently estimated to cost 2.8 million
dollars. The completion of the Remedial Design will provide more
accurate information to determine the degree to which removal
will take place. At that point a more accurate/ cost estimate for
the selected remedy can be incorporated into the Remedial Design.

Utilization of Permanent Solutions and Alternative Treatment Technologies or
Resource Recovery Technologies to the Maximum Extent Practicable (MEP)

As stated previously/ the Chemicals of Potential Concern are
metals and they cannot be destroyed/ permanence of remedial
alternatives must be judged in terms of the elimination of
exposure to these compounds and/or the degree of alteration of
their bioavailability. Removal of contaminated sediment from
streams is the most permanent solution possible in terms of the
elimination of the potential for exposure. The selected remedy
allows for monitoring of the streams to see if natural recovery
proves effective in reducing the bioavailability of the chemicals
of potential concern. Any sediments that are destined for
offsite disposal will be stabilized if they fail the toxicity
characteristic leaching procedure (TCLP).

Preference for Treatment as a Principle Element

At this time there is no known effective treatment technology for
the chemicals of potential concern that would allow treatment to
be a principle element of the selected remedy.
RESPONSIVENESS SUMMARY

The following questions were received by DEQ a the public meeting
held on May 2, 1996. No written questions were submitted. -

1. Citizen asked about EPA calculations for land application of
sludge containing heavy metals. Is there any effect when sludge
is applied time after time?
The Remedial Coals for agricultural land use
based on EPA's calculations for land application
of heavy metal containing sludge. The EPA figures
are based on maximum lifetime loading of sludge to
soil. In other words, while sludge may be applied
again and again, there is a limit to the total
amount of metal which can end up in soil. This
27
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limit is considered by EPA to be a safe level in
agricultural soil. That limit is the basis for
the Remedial Goals for agricultural lands. Please
refer to the Ecological Risk Assessment and Feasi-
bility Study for more details.

2. A citizens was concerned about Figure eight. The SP3 selec-
tion in Figure eight had the highest overall rating and the
highest threshold rating. Why was SP5a selected over SP3?

The actual selected remedy is a combination of Sd-3 and Sd-
5a. The main difference is the the lower reach will be re-
moved as well as the upper reach of the tributary. Total
removal will produce a higher overall rating and threshold
rating.

3. A citizen was concerned about control of airborne material
when soil removal was undertaken.

During removal, the control of airborne materials will be
done. The actual method will be presented in the Remedial
Design but one possible method is to keep the material damp
and the trucks hauling the material covered.

4. Citizen asked if was there a way to prevent any possible
pollution from being washed downstream during sediment removal
from creek beds.

This will be addresed in the Remedial Design but one possi-r
JbJe method will be coffer dams..

5. Citizen asked-about coordination between offsite and onsite
activities. Can ons'lte activities be taken care of to fit into
the offsite project timeline so that things do not have to be
done again. What is the timeline for this project?

The offsite activities will be coordinated with the schedule
of onsite activities as well as the Operable Unit One ac-
tivities. There -is no point in removing contamination down-
stream until the areas upstream are remediated. A schedule
of these activities will be in the Remedial Design.
28
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6. Citizen asked a question not directly related to the proposed
plan for OU2, "Have the piles at ZCA been sprayed recently, in
view of the inclement weather and reports of 100 mph winds, to
make sure they are not depositing any airborne material?

yes. The piles are sprayed on a regular basis and
air monitoring at the fence line is ongoing.
WHATS NEXT?

The Remedial Design report will be completed by spring of 1997.
The selected remedial action alternative will be implemented once
the Remedial Design is completed and approved by DEQ and the
remedial action for OU1 is complete along witii any action neces-
sary on the National Zinc Site.

FOR MORE INFORMATION

The RI/FS reports or any other documents contained in the updated
Administrative Record file for the National Zinc Site, are
available at the information repositories listed below.

Bartlesville Public Library
600 S. Johnstone
Bartlesville, Oklahoma 74005

Bartlesville Chamber of Commerce
201 S.W. Keeler
Bartlesville, Oklahoma 74004

Westside Community Center
501 s.w. Bucy .A
Bartlesville, 'Oklahoma 74004

Department of Environmental Quality
Waste Management Division
1000 NE 10th Street
Oklahoma City, Oklahoma 73117-1212

If you have any questions about this project/ please call:

Ms. Monty Elder at 1-800-869-1400 or
Mr. Scott Thompson at (405)271-7213.
29
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GLOSSARY

Apparent effects threshold (AET) Analogous to the preliminary
remediation goals (PRG).

Applicable or Relevant and Appropriate Requirement (ARAR) — The
federal and state laws or regulations that a cleanup must usually
attain. An applicable requirement is a promulgated federal or
state standard that specifically addresses a hazardous constitu-
ent, remedial action, location, or other circumstance at a site.
To be applicable, the remedial actions or the circumstances at
the site must be within the intended scope and authority of the
requirement. A relevant nnd appropriate requirement is a promul-
gated federal or state requirement that addresses problems or
situations similar to those encountered at a site, even though
the requirement is not legally applicable.

Operable Unit — (OU1 or OU2) A distinct portion of a Superfund
site or a distinct action at a Superfund site. An operable unit
may be established based on a particular type of contamination,
contaminated media (e.g., soils, water), source of contamination,
or some physical boundary or restraint;

Preliminary remediation goal (PRG) — An initial specific con-
taminant concentration (e.g., in soil) that is protective of
human health and the environment and complies with ARARs. Pre-
liminary remediation goals are used during the evaluation of
remedial action .alternatives.

Remedial action alternative — A potential method for cleaning up
a site. Remedial action alternatives are developed from general
response actions te.-g., removal and disposal), technologies
(e.g., chemical treatment), and process options (e.g., stabiliza-
tion) after screening. Possible remedial action alternatives
include no action, institutional controls, onsite containment
with no treatment, and removal and disposal options with or with-
out treatment.

Remediation level — The final cleanup level (i.e., specific con-
taminant concentration in soil) that is established upon comple-
tion of the remedial investigation, feasibility study and any
other necessary additional studies.
30
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Remedy or remedial action — Those actions consistent with the
permanent remedy taken instead of, or in addition to, removal
action in the event of a release of hazardous substances to the
environment so that they do not cause substantial danger to pre-
sent or future public health or welfare or the environment.

Removal action — The cleanup or removal of released hazardous
substances from the environment to minimize or mitigate damage to
the public health or welfare or to the environment.
LIST OF ACRONYMS

ARARs - applicable or relevant and appropriate requirements
CERCLA - Comprehensive Environmental Response, Compensation, and
Liability Act
CoPCs - chemicals of potential concern
DEQ - Department of Environmental Quality
EPA - Environmental Protection Agency
FFS - Focused Feasibility Study
HFO - hydrous-ferric-oxide-
MOU - memorandum of understanding
NCP - National Oil and Hazardous Substances Pollution Contingency
Plan
NPL - National Priorities List
OU1 - Operable Unit One
OU2 - Operable Unit Two
PRGs - preliminary remediation goals
PPE - personal protective equipment
PRPs - potentially responsible parties
PTI - PTI Environmental Services
RAOs - remedial action objectives
RBCs - risk-based concentrations
RCRA - Resource Conservation and Recovery Act of 1976
RI/FS - remedial investigation and feasibility study
ROD - Record of Decision
SARA - Super fund Amendments and Reauthorization Act
Site - National Zinc Site in Bartlesville, Oklahoma
TCLP - Toxicity Characteristic Leaching Procedure
ZCA - Zinc Corporation of America
31
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TABUS
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TABLE 2. SUMMARY OF REMEDIAL ACTION ALTERNATIVES FOR DETAILED ANALYSIS

Sediment Alternatives
Sd-1 No action (including natural recovery)
Sd-2 Institutional controls*
Sd-3 Partial removal, stabilization, and offsfte disposal6 and partial natural recovery*-0
Sd-4 Partial removal, stabilization, and offsfte disposal6 and partial tributary rechannelization
and capping the existing channel with soil*"
Sd-5a Removal, stabilization, and offsite disposal**6
Sd-Sb Removal, stabilization, and onstte disposala.c

a Alternative assumes that source control activities at the ZCA facility and adjacent industrial properties
will be implemented.
b Offsfte disposal is used as a representative disposal option and does not preclude the use of onsite
disposal.
c Alternative includes use of passive metal adsorption media after sediment removal to control potential
ongoing sources of dissolved metals in surface water.
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TABLE 3. EVALUATION CRITERIA
Threshold Criteria
1. Overall protection of human health and the environment
How well does the alternative protect human health and the environment, both during
and after construction?
2. Compliance with federal and state environmental standards
Does the alternative meet all applicable or relevant and appropriate state and federal
laws?
Balancing Criteria
3. Cost
What are the estimated costs of the alternative?
4. Long-term effectiveness and performance
How well does the alternative protect human health and the environment after
completion of cleanup?
What, if any. risks remain at the Site?
5. Reduction of toxicfty. mobility, or volume through treatment
Does the alternative effectively treat the contamination to significantly reduce the
toxicity, mobility, and volume of the hazardous substance?
6. Short-term effectiveness
Are there potential adverse effects to either human health or the environment during
construction or implementation of the alternative?
How fast does the alternative reach the cleanup goals?
7. Implementability
Is the alternative both technically and administratively feasible?
Modifying Criteria
8. State acceptance
Typically what are the state's comments or concerns about the alternatives
considered and the preferred alternative? Federal acceptance will be considered in
lieu of state acceptance.
9. Community acceptance
What are the community's comments or concerns about the preferred alternative?
Does the community generally support or oppose the preferred alternative?

Note: The Oklahoma Department of Environmental Quality (DEQ) uses nine criteria to evaluate the
remedial action alternatives. With the exception of the "no action" alternative, all alternatives must meet
the first two "threshold" criteria. DEQ uses the next five criteria as "balancing* criteria for comparing
alternatives and selecting a preferred alternative. After public comment, DEQ may alter its preference on
the basis of the last two "modifying* criteria.
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FIGURES
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^H Operable Unit 2 study area

vvV-v* Surface water drainage
evaluation area
Figure 1. Operable Unit 2 study area location.
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LEGEND
• Surface water/sediment
sampling stations

?••;•£;; Upper and tower reaches
ECOSIfX
we*--
700
Meet
Figure 2. Areas considered for sediment removal and natural recovery.
CS26-12-1001/1T/S6
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Clean material used for cap over
metals-enriched sediment and soils
Upland
New channel location
Metals-enriched sediments and soils
Not to scale
Figure 3. Cross section of lower reach of the North Tributary for rechannelization.
C626-H-10 01/17/98
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removed and replaced wtth dean fill
Figure 4* Cross section of lower reach of the North Tributary for sediment removal.
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