Superfund Record of Decision Tar Creek (Ottawa County) OU 2 Ottawa County OK


                                    EPA/ROD/R06-97/126
                                    1997
EPA Superfund
     Record of Decision:
     TAR CREEK (OTTAWA COUNTY)
     EPA ID:  OKD980629844
     OU02
     OTTAWA COUNTY, OK
     08/27/1997

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                                              RECORD OF DECISION
                                               RESIDENTIAL AREAS
                                                OPERABLE UNIT 2
                                           TAR CREEK SUPERFUND SITE

                                            OTTAWA COUNTY,  OKLAHOMA
                                                 Prepared by:

                                     U.  S.  Environmental Protection Agency
                                                   Region 6
                                               1445 Ross Avenue
                                              Dallas,  Texas  75202

                                                 AUGUST 1997

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                                              RECORD OF  DECISION
                                           CONCURRENCE DOCUMENTATION

                                                    FOR THE

                                           TAR CREEK SUPERFUND  SITE
                                            OTTAWA COUNTY, OKLAHOMA
                                      OPERABLE UNIT 2, RESIDENTIAL AREAS

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                                                  DECLARATION
                                           TAR CREEK SUPERFUND SITE
                                            OTTAWA COUNTY OKLAHOMA
                                               RESIDENTIAL AREAS
                                             RECORD OF DECISION

Statutory Preference for Treatment as a Principal Element is Not Met and Five-Year Review is not
Required.

SITE NAME AND LOCATION

Tar Creek Superfund Site
Ottawa County, Oklahoma
Residential Areas

STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected remedial action for the residential areas of the
Tar Creek Superfund Site (hereinafter, the "Site"), in Ottawa County, Oklahoma, developed in
accordance with the Comprehensive Environmental Response, Compensation, and Liability Act, as
amended by the Superfund Amendments and Reauthorization Act  (SARA),  ("CERCLA") , 42 U.S.C. °9601
et seq., and to the extent practicable, the National Continqency Plan  (NCP) 40 CFR Part 300.
This decision is based on the Administrative Record for the Site.

The State of Oklahoma and the Indian Tribes involved with the Site concur on the selected
remedy.

ASSESSMENT OF THE SITE

Actual or threatened releases of hazardous substances from the Site, if not addressed by
implementinq the response action selected in this Record of Decision ("ROD"), may present an
imminent and substantial endanqerment to public health, welfare,  or the environment.

DESCRIPTION OF THE REMEDY

The remedy addresses the contamination from mininq waste in the residential areas of the Site.
The major components of the selected remedy include:

       S    Excavation of lead-contaminated surface soil in residential areas;
       S    Replacement of excavated soil with clean soil and restoration of the remediated
            areas;
       S    Disposal of excavated soil on-Site in dry mininq waste areas remote from the
            residential areas or, in the event of inability to dispose of excavated materials
            on-Site, disposal off-Site in an approved landfill;
       S    Coverinq or replacement of mininq waste in traffic areas located near residences;
       S    Restriction of access to mininq waste areas located near residences by use of
            physical barriers (e.q., fences and warninq siqns); and,

       S    County-wide implementation of institutional controls, includinq community protective
            measures, to supplement enqineerinq response actions.

STATUTORY DETERMINATIONS

The selected remedy is protective of human health and the environment,  complies with Federal and

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State requirements that are legally applicable or relevant and appropriate to the remedial
action,  and is cost-effective.  The selected remedy utilizes permanent solutions and alternative
treatment technologies to the maximum extent practicable for the Site; however,  because
treatment of the soil lead in the residential areas was not found to be practicable or cost
effective, this remedy does not satisfy the statutory preference for treatment as a principal
element of the remedy.  High concentrations of soil lead are addressed under the remedy selected
in this ROD; however, the mobility of the soil lead is low, and the concentrations of lead are
not so high as to be several orders of magnitude above levels that allow for unrestricted use
and unlimited exposure.  Therefore, the soil lead is not considered a principal threat under the
NCP; consequently, there is no expectation under the NCP that the soil lead be treated.

Because hazardous substances will not remain in the residential areas above concentrations that
pose a risk to human health, five-year reviews are not necessary for the selected remedy.

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                                              TABLE OF CONTENTS

       TITLE                                                                 PAGE

I.     Site Name,  Location,  and Description	1

II.    Site History and Enforcement Activities	1

III.   Highlights  of Participation 	  4

IV.    Scope and Role of Operable Units	6

V.     Summary of  Site Characteristics	7

VI.    Summary of  Site Risks	14

VII.   Description of Alternatives	21

VIII. Summary of Comparative Analysis of Alternatives	30

IX.    Selected Remedy	41

X.     Statutory Authority Findings and Conclusions of Law	44

XI.    Documentation of Significant Changes	49

                                          LIST OF TABLES  AND FIGURES

TABLES

Table 1   Summary of Analytical Results for Lead
Table 2   Remedial Action Alternative Cost Summary
Table 3   Potential Chemical-Specific ARARs
Table 4   Potential Location-Specific ARARs
Table 5   Potential Action-Specific ARARs


FIGURES

Figure 1 Tar Creek Superfund Site Map


APPENDIX

A.  Responsiveness Summary
B.  ODEQ Comment Letter
C.  ITEC Comment Letters
D.  Quapaw Tribe Comment Letter
E.  Wyandotte Tribe Comment Letter
F.  Administrative Record Index

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DECISION SUMMARY
TAR CREEK SUPERFUND SITE
OTTAWA COUNTY, OKLAHOMA
RESIDENTIAL AREAS

I. SITE NAME, LOCATION AND DESCRIPTION

The Tar Creek Superfund Site (the "Site") is located in Ottawa County, Oklahoma. The U.S.
Environmental Protection Agency (EPA) is addressing the contamination from mining waste in the
residential areas of the Site. The Site is composed of the Oklahoma portion of the Tri-State
Mining District. The Site consists of the areas of Ottawa County impacted by mining waste. The
Site includes all of the area (approximately 40-sguare miles) in northern Ottawa County where
lead and zinc mining operations were conducted (the "mining area"). The approximate boundaries
of the mining area are shown on Figure 1. The Site also includes communities in Ottawa County
outside the mining area that are also contaminated with mining waste. The Tri-State Mining
District covers hundreds of sguare miles in southwestern Missouri, southeastern Kansas, and
northeastern Oklahoma. The principal on-Site cities located in the mining area include Picher,
Cardin, Commerce, Quapaw, and portions of North Miami. Other on-Site cities, including Miami,
are located in proximity to the mining area and have been impacted by the mining waste disposed
of on the Site. Approximately 15,000 people live on-Site in the mining area and in communities
in close proximity to the mining area on-Site. According to available literature, mining began
at the Site in the early 1900's and ceased in the 1970's. The ore removed from the mines was
milled locally to produce ore concentrates, which were generally shipped to other locations
outside of Ottawa County for smelting.

II. SITE HISTORY AND ENFORCEMENT ACTIVITIES

The Tar Creek Superfund Site first came to the attention of the State of Oklahoma and EPA
in 1939 when acid mine drainage began flowing to the Site surface from underground mines through
abandoned mine shafts and boreholes. The Governor of Oklahoma formed the Tar Creek Task Force
to investigate the effects of acid mine drainage on the area's surface and ground water. Based
upon the information discovered by the Tar Creek Task Force, EPA proposed, in July 1981, to add
the Site to the Superfund National Priorities List (NPL), 40 CFR Part 300, Appendix B. The NPL
means the list, compiled by EPA pursuant to CERCLA section 105, of uncontrolled hazardous
substance releases in the United States that are priorities for long-term remedial evaluation
and response. The Site was added to the NPL in September 1983.

In the early years from about 1918 to about 1930, over 200 mills were operating at the
Site. Many of the mining operations were conducted underground at depths ranging from
approximately 90 to 320 feet below ground surface. It has been estimated that underground lead
and zinc mines underlie approximately 2,540 acres in Ottawa County, Oklahoma.

The by-products of the mining operation were discarded mining and milling tailings
(mining, milling, and possible smelter wastes, are collectively referred to in this document as
mining wastes). The mill tailings, locally know as chat, are primarily composed of small chert
fragments, intermingled with sand-sized particles. After the excavated rock was processed and
the metal ore extracted, the mining tailings that remained were deposited into piles that were
up to 200 feet in height. Many of these chat piles remain on the Site, including some piles
which are over 100 feet high. An inventory conducted in the 1980's indicated that approximately
2,900 acres in Ottawa County, Oklahoma were at one time covered by mining waste. The inventory
also indicates that there were approximately 265 chat piles in existence during the mining
period and that only 119 were still in existence in 1980. This same inventory indicated that
approximately 48 million cubic yards of chat remained on about 900 acres on the Site. In
addition to piles of mining wastes, a large but lesser guantity of floatation pond tailings from

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the floatation milling process was produced. Most of the floatation ponds have since evaporated
leaving behind a very fine mining waste sediment which remains on the Site. A numerical
guantity estimate is not available, although the guantity of floatation pond tailings probably
measures in the millions of tons. The 1980 inventory indicated that approximately 800 acres
were utilized for tailings ponds. Over the years, the mining wastes have been used or continue
to be used for a variety of purposes including the following: railroad ballast; concrete and
asphalt aggregate; sandblasting sand; sandbag sand; roadway, driveway, alleyway, and parking lot
aggregate; general fill material in residential areas; and impact-absorbing material in
playgrounds. The EPA believes that there are uses of mining waste that can be protective of
human health or the environment. Such uses include use as construction material when the mining
waste is bound up with other materials and solidified (e.g., when it is used in concrete or
asphalt). The mining waste should not be put to uses where it is exposed in an unbound state
(e.g., it should not be used as fill in residential areas, as gravel for driveways, as gravel
for roads or alleyways in residential areas, or as playground material).

Enforcement

The previous work at the Site, addressed in the June 6, 1984 Record of Decision (ROD), is
referred to in this 1997 ROD as Operable Unit Number 1 (OU1). OU1 addressed the on-Site surface
water impacted by mine discharges and the ground water on the Site. The EPA entered into a
consent decree under Sections 107 and 122 of the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) , 42 U.S.C.00 9607 and 9622, with six mining companies
(hereinafter the Companies), settling their liability for costs paid by the United States in
responding to the release or threat of release of hazardous substances as described in the 1984
ROD (i.e., the costs related to OU1). In 1996, EPA settled its claims regarding the Site with a
bankrupt mining company which had the largest operation at the Site. On August 25, 1995, EPA
issued a notice to the Companies or to their corporate successors (hereinafter the Companies and
their corporate successors are referred to as the Companies), and to the U.S. Department of the
Interior (DOI) which may be a potentially responsible party (PRP) under CERCLA's liability
provisions. In that notice, EPA gave the Companies and DOI the opportunity to conduct or
finance the removal activities described in EPA's August 15, 1995, Action Memorandum. The
Action Memorandum generally called for the excavation and on-Site disposal of lead-contaminated
soil in High Access Areas (HAAs) (HAAS are areas which children freguently visit such as
playgrounds, day-cares, and parks). The Companies and DOI did not undertake the removal;
conseguently, EPA proceeded with the removal action for the HAAs on its own.

The EPA also issued a Special Notice to the Companies and to DOI on November 17, 1995. In
the Special Notice, EPA gave the Companies and DOI the opportunity to undertake the Remedial
Investigation and Feasibility Study (RI/FS) and remedial design (RD) for the remedial response
action to address contamination in the residential areas on the Site. The Companies and DOI did
not undertake the RI/FS/RD. As an alternative to RI/FS/RD, the Companies and DOI offered to
perform a Community Health Action and Monitoring Program (CHAMP). The CHAMP generally calls for
monitoring the health of the children in the contaminated residential areas, for thorough
cleaning of homes in the contaminated area, and for education of the residents regarding the
avoidance of contamination. The EPA encouraged the Companies and DOI to undertake the CHAMP,
which they did; but, housecleaning and education do not provide the sort of permanent remedy
that the Superfund law reguires. Conseguently, EPA went forward with RI/FS/RD on its own.

In order to address the imminent and substantial endangerment to human health posed by the
lead-contaminated soil in the residential areas on the Site, EPA issued a March 21, 1996, Action
Memorandum calling for a removal action to address the contamination. At the time the Action
Memorandum was issued, EPA sent a letter to the Companies and DOI notifying them that EPA was
proceeding with the removal in residential yards. In the letter, EPA told the Companies and DOI
that EPA would not delay the removal action in order to negotiate; however, EPA gave the

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Companies and DOI the opportunity to conduct or finance the removal activities in progress. The
Companies and DOI did not offer to take over the removal actions.

III. HIGHLIGHTS OF COMMUNITY PARTICIPATION

This decision document or ROD presents the EPA-selected remedial action for the
residential areas of the Tar Creek Superfund Site, Ottawa County, Oklahoma chosen in accordance
with CERCLA, as amended by the Superfund Amendments and Reauthorization Act (SARA) and, to the
extent practicable, the National Contingency Plan (NCP). The decision for the Site is based on
the Administrative Record. An index to the Administrative Record is included as Appendix F to
this ROD.

The public participation reguirements of CERCLA Subsection 113(k) (2) (B) (i-v) and 117, 42
U.S.C. Subsection 9613(k)(2)(B)(i-v) and Section 9617, were met during the remedy selection
process, as illustrated in the following discussion.

Beginning in Spring 1994, and continuing to the present, EPA has conducted a series of
community meetings and discussions near the Site. In these meetings, the Oklahoma Department of
Environmental Quality (ODEQ) and EPA officials met with citizens, local officials, Tribal
leaders, Tribal members, and State and Federal agencies regarding Site issues. The EPA
completed a Community Relations Plan (CRP) for the Site residential remedial action in June
1995, and released the CRP to the public. The CRP was prepared in order to identify and address
community concerns. Copies of the CRP are located in the information repository maintained at
the Site at the Miami Public Library in Miami, Oklahoma and at the EPA Region 6 Office in
Dallas, Texas. A series of seven community meetings have been conducted over the course of the
project at the Site. During these meetings, EPA informed the public of the progress of the
removal activities and the RI/FS. The EPA distributed fact sheets at these meetings. The fact
sheets summarized the progress of the project up to the date of the meeting in guestion and also
explained the data that had been gathered. At the community meetings, EPA discussed field work
and asked community members for information about the Site. The EPA mailed a fact sheet, which
summarized EPA's Proposed Plan of Action to address contamination in the residential areas, to
all individuals on the Site mailing list. The Site mailing list contains names of those who
have submitted comments to EPA, the Companies and DOI, State and local officials, natural
resource trustees, Tribal officials, and those community members who have attended meetings
regarding the Site.

The Site mailing list has been continuously updated as Site activities progress. On May
1, 1995, EPA published a notice in the Miami News-Record, a major local newspaper of general
circulation, which announced to the public that Technical Assistance Grants were available. The
EPA may provide Technical Assistance Grants, under Section 117 of CERCLA, 42 U.S.C. Section
9617, to any group of individuals that may be affected by a release of hazardous substances in
order for such a group to obtain technical assistance in interpreting information with regard to
the nature of the hazard and the CERCLA remediation process.

In January 1987, EPA released the Remedial Investigation (RI) Report for the Site. In
February 1997, EPA released the Feasibility Study (FS) Report for the Site. On March 12, 1997,
EPA released its Proposed Plan for the remediation of the residential areas of the Site. The
EPA made the RI Report, the FS Report and the Proposed Plan, along with the administrative
record file, available to the public at information repositories maintained at the Miami Public
Library, Miami, Oklahoma, and at the EPA Region 6 Office in Dallas, Texas. The notice of
availability for these documents was published in the newspaper of record, the Miami March 16,
1997, and was also published in the Tri-State Tribune on March 13, 1997, through March 20, 1997.

On February 27, 1997, the ODEQ and EPA held an open house in Picher, Oklahoma to inform

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the public of the findings of the Remedial Investigation and Feasibility Study reports including
the results of the Baseline Risk Assessment.  The Baseline Risk Assessment is a study which
characterizes the current and potential threats to human health and the environment that may be
posed by the release of hazardous substances at a site.  A public meeting was held in Picher,
Oklahoma on March 27, 1997, to inform the public about the Proposed Plan of action for the
residential areas of the Site.  Also, at this Picher public meeting, representatives from EPA
solicited comments and answered guestions about the Site, about the remedial alternatives under
consideration, and about the Proposed Plan.  The EPA held a 30-day public comment period
regarding the Proposed Plan, the RI and FS Reports, and the Administrative Record from March 17,
1997, to April 16, 1997.  The public comment period was extended to May 16, 1997, due to a
reguest for an extension.  The public comment period was subseguently extended again to May 23,
1997, due to an additional reguest for an extension.  A notice announcing the extension of the
public comment period was published in the Miami New-Record, on April 16, 1997, and April 17,
1997.  A response to verbal and written comments received during the public comment period is
included in the Responsiveness Summary, which is part of this ROD  (Appendix A).

IV.    SCOPE AND ROLE OF THE OPERABLE UNITS

       The Tar Creek Superfund Site is a former lead and zinc mining district.  The years of
mining and milling activities on the Site resulted in widespread contamination of the
environment at the Site.  The Superfund response activities at the Site are complex and,
accordingly, they have been divided into functional units, called operable units, to facilitate
Site cleanup.  Each operable unit addresses a discrete release, threat of release, or a pathway
of exposure found at the Site.  The cleanup activities related to the millions of tons of mining
waste that were deposited on the surface of the ground at the Site have been designated as
Operable Unit 2 (OU2).  This ROD and the Proposed Plan were developed for the residential area
portion of OU2.  That is, the selected response for the residential areas in OU2 addresses only
a portion of the widespread contamination at the Site.  Additional response actions will be
reguired to address the remaining contamination in OU2 and in the rest of the Site.  For the
portion of OU2 which is the subject of this ROD, the land use is currently residential, and this
land is expected to remain in residential use in the future.  OU1 contains the portions of the
Site in which surface water and ground water have been contaminated as a result of mining
operations.  The EPA's 1984 ROD was intended to address the surface water and ground water in
OU1.   The remedial action which EPA has selected as documented in this ROD, addresses cleanup of
residential areas of the Site which are contaminated with mining wastes.  The term "residential
areas" as used in this ROD document is not limited solely to single-family residences, but also
includes other residential properties  (eg., apartments, and condominiums) and high access areas
(HAAs) which are places freguented by children such as day-care centers, playgrounds, and
schoolyards.

Remedial Action Objective

       A remedial action objective (RAO)  is a general description of what a given remedial action
will accomplish.  RAOs aimed at protecting human health and the environment should specify:  (1)
the contaminants of concern;  (2) exposure routes and receptors; and, (3) an acceptable
contaminant level or range of levels for  each exposure medium (i.e., a PRG)  (see 55 Fed. Reg
8666, 8712-8713, March 8, 1990).  Results of the Baseline Human Health Risk Assessment(BHHRA)
issued August 1996, indicate that exposure to lead in soil is the primary human health risk for
the Site.  The Remedial Action Objective (RAO)  for the Site is as follows:

              Reduce ingestion by humans,  especially children,  of surface soil in residential
              areas contaminated with lead at a concentration greater than or egual to 500 parts
              per million (ppm).

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Principal Threats

Principal threats are characterized as waste that cannot be reliably controlled in place,
such as liquids, highly mobile materials (eg., solvents), and high concentrations of toxic
compounds (e.g., concentrations several orders of magnitude above levels that allow for
unrestricted use and unlimited exposure) [(see 55 Fed. Reg. 8666, 8703 (March 8, 1990)]. The
lead-contaminated residential surface soil at the Site is generally classified as low level
threat waste rather than principal threat waste. Although the soil is contaminated above
health-risk-derived levels (i.e., the Remediation Goal level (see infra, Section VI)], it is not
contaminated an order of magnitude above the remediation goals. Also, the lead-contaminated
soil is not generally considered mobile due to the physical and chemical properties of the soil.
The soil is a solid and not a liquid; moreover, the lead strongly adheres to the soil particles
and does not easily migrate when subjected to ground water flow. The lead-contaminated soil
could physically be controlled in place with little likelihood of migration; however, the
practicability of containment of contaminated soil in a residential setting is doubtful for
reasons discussed later in this document under Section VIII ("Summary of Comparative Analysis of
Alternatives").

V. SUMMARY OF SITE CHARACTERISTICS

The EPA began environmental investigations at the Site in 1982. An RI/FS for the Site was
completed in December 1983. Based upon the 1983 RI/FS, on June 6, 1984, EPA issued a ROD
memorializing the remedy selected for certain portions (Operable Unit 1) of the Site. The
Operable Unit 1 ROD addressed two concerns: 1) the surface water degradation of Tar Creek, a
stream located on the Site, by the discharge of acid mine water; and, 2) the threat of
contamination of the Roubidoux Aquifer which lies under the Site. At the time the ROD was
issued, EPA was concerned that the Roubidoux Aquifer, which supplies water for domestic use in
the Site area, would be contaminated by downward migration of acid mine water from the
contaminated Boone Aquifer which is located in geologic strata which occur above the Roubidoux.
Specifically, EPA was concerned that contaminated ground water from the Boone would migrate to
the Roubidoux through abandoned wells connecting the Boone with the Roubidoux. Pursuant to
EPA's ROD for Operable Unit 1, in order to address the surface water contamination in Tar Creek,
dikes were constructed to reduce the inflow of surface water into collapsed mine shafts. By
reducing the flow of surface water into the collapsed shafts, EPA's intention was to eliminate
or reduce the outflow of contaminated water from the shafts to the surface and subsequently to
Tar Creek. Also pursuant to EPA's ROD, in order to address the potential contamination of the
Roubidoux Aquifer, abandoned wells which penetrated the Roubidoux formation were plugged. The
construction of the Operable Unit 1 remedy was completed in December 1986.

At the time that the 1984 ROD was written, EPA believed that the remedy in the 1984 ROD
would be protective of human health and the environment at the Site in general. The 1984 ROD
did not address the tailings piles (chat piles) and ponds (floatation ponds) and other mining
waste on the ground surface at the Site. In April 1994, pursuant to CERCLA Section 121(c), 42
U.S.C. ° 9621(c), EPA conducted a Five-Year Review of the remedial action for Operable Unit 1 to
assure that human health and the environment at the Site in general were being protected by the
remedial action being implemented at Operable Unit 1. New information gathered during the 1994
Five-Year Review, including information regarding elevated levels of lead in the blood of
children living on the Site, led EPA to the conclusion that additional investigations of the
effect of Site mining wastes on human health were necessary. Specifically, in 1994, EPA
received from the Indian Health Service test results concerning the concentration levels of lead
in the blood of Indian children living in the area. The test results indicated that
approximately 35 percent of the Indian children tested had concentrations of lead in their blood
which exceeded 10 micrograms per deciliter (ug/dL), which is the level considered elevated for
young children by the Centers for Disease Control (CDC) (see Preventing Lead Poisoning in Young

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Children, A Statement by the Centers for Disease Control, October, 1991).

       The definition of elevated blood lead in young children is the threshold level at which
adverse health effects have been shown to occur.  The previous lead statement issued by CDC in
1985 had defined the level of 25 ug/dL as elevated.  When the ROD was signed in 1984, the level
of 30 ug/dL was considered elevated by CDC.  The EPA presented this new information, regarding
high concentrations of lead in the blood of Indian children who lived in the Site area, as part
of the Five-Year Review report for the Site which was published in April 1994.  In the Five-Year
Review report, EPA recommended, based on this new information, that the mining waste deposited
on the surface of the ground be investigated to determine if additional remediation, beyond the
remediation carried out, for Operable Unit 1, at the Site was needed to protect human health or
welfare, or the environment.

Site Assessment Activities

       From August 1994 through July 1995,  EPA through its removal program (the removal program
is generally the part of the Superfund program that conducts emergency or early response
activities whereas the remedial program is the part which conducts long-term response
activities) conducted sampling in order to determine the nature and extent of contamination at
the Site.  Sampling was generally divided into two phases.  The first phase (Phase I) of
sampling took place in High Access Areas (HAAs) which are places frequented by children such as
day-care centers, playgrounds, and schoolyards.  The second phase  (Phase II)  of sampling took
place in residential yards on the Site.  The site assessment activities were concentrated at
HAAs and residential properties since mining wastes had been observed in many of these locations
throughout the Site.  Moreover, the HAAs are frequented by young children, the residential
properties are inhabited or potentially inhabited by young children,  and young children are the
segment of the population most susceptible to lead poisoning.  A total of 28 HAAs and 2,070
residential properties were sampled during the site assessment. The site assessment data was the
basis of EPA's Baseline Human Health Risk Assessment (BHHRA) issued in August 1996 and EPA's
Residential RI Report issued in January 1997.

       The EPA's site assessment investigations explored the possibility that humans living on
the residential areas of the Site may be exposed to contamination through various exposure
pathways including ingestion of contaminated soil, surface water or ground water, inhalation of
contaminated dust in the air, and dermal contact with contaminated water or soil.  However, EPA
studies found that, under the conditions found in the residential areas of the Site, ingestion
of contaminated soil was the only exposure pathway that could pose a significant risk to human
health.

       The EPA's site assessment investigations, including the BHHRA,  led EPA to the conclusion
that lead contamination in soil in residential areas on the Site posed an imminent and
substantial endangerment to human health—especially to children's health; consequently, EPA
conducted the removal actions described in the Section of this ROD entitled "Current Removal
Actions" which is part of Section V ("Summary of Site Characteristics").  This same endangerment
is addressed by the remedial action selected for the remediation of the Site and described in
this Record of Decision (ROD).

Nature and Extent of Contamination

       Characterization of the nature and extent of contamination for the residential areas of
the Site is presented in the Residential RI Report and in the BHHRA Report.  During the site
assessment, field investigations consisted of the following main sampling elements:

       •    Sampling of Study Area homes - The Study Area means the mining area of Ottawa County

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which was the subject of the BHHRA.

• Sampling of Study Group homes - The Study Group is the 100 homes in Picher where
multi-media environmental samples were taken.

• Sampling of Reference Area/Background homes - The Reference Area/Background homes are
15 homes in Afton, Oklahoma. These 15 homes are outside of the mining area. The EPA
took multi-media environmental samples at these homes so that the samples could be
compared to samples taken within the mining area.

Ambient air sampling.

The Study Area consisted of the residential areas of Picher, Cardin, Quapaw, Commerce, and
portions of North Miami. During the conduct of this investigation, EPA collected site-specific
sampling data at residential homes in Picher (Study Group) in order to evaluate the long-term
risk associated with exposure to Site contaminants.

Samples were also collected from homes in Afton, Oklahoma, as a background reference to
compare with the samples taken from the mining area. Afton is outside of the mining area and
generally does not have the mining waste contamination found in the mining area on the Site.
Ambient air samples were taken during a 3-month period from 5 monitoring stations located in
Picher. A background air-monitoring station was located 3 miles west of Picher.

Air monitoring indicated that contaminant concentration levels in the ambient air were not
above health-risk-derived levels. None of the lead concentrations in ambient air exceeded the
National Ambient Air Quality Standard for lead of 1.5 ug/m 3 (maximum guarterly average).

A summary of the lead contamination levels from samples of yard soil, garden soil, and
garden produce from residential homes investigated in Picher and Afton is presented in Table 1.
As shown in Table 1, the average concentrations of lead in the yard soil and garden soil samples
taken at the Study Group homes in Picher were found to be approximately 10 times greater than
the average lead concentrations in the yard soil and garden soil samples taken at the Reference
Area homes in Afton. For the garden produce, differences in lead content between the Study
Group samples and the Reference Area samples were less than 1 percent.

Current Removal Actions

Based on the Phase I site assessment sampling (August 1994 to October 1994), EPA began
removal actions at various HAAs on the Site. Removal actions are generally the early response
actions taken by the Superfund progran, to address the most immediate and highest risk first.
The action memorandum authorizing the removal response action at the HAAs was issued August 15,
1995. The removal action at HAAs was triggered by widespread surface soil contamination greater
than or egual to 500 ppm lead and/or 100 ppm cadmium. Excavations at HAAs vary in depth as well
as in the cleanup level selected. The excavation criteria utilized during the HAA response were
500 ppm lead and/or 100 ppm cadmium from 0 to 12 inches of soil depth, and 1000 ppm lead and/or
100 ppm cadmium from 12 to 18 inches of soil depth (maximum excavation depth of 18 inches).
That is, if lead or cadmium were found at concentration levels which exceeded 500 ppm and 100
ppm, respectively, in the first 12 inches of soil, that soil was excavated, and, if lead or
cadmium were found in soil at depth ranges of 12 to 18 inches at concentration levels which
exceeded 1000 ppm or 100 ppm, respectively, then that soil was excavated. All excavated areas
were back-filled with clean soil. On large properties, such as schools and parks, where
unauthorized private excavation could be easily controlled, the excavation criteria were
modified. The excavation criteria for these school and park areas were modified to 500 ppm lead
and/or 100 ppm cadmium from 0 to 12 inches soil depth (maximum excavation depth of 12 inches).

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A total of 28 HAAs were evaluated. Seventeen of the 28 HAAs were determined to potentially
require some sort of EPA response action. The EPA initiated response actions at HAAs in
September 1995. The removal actions taken during this HAA response eliminated or reduced direct
contact with contaminated surface soil at these HAAs. The continued effectiveness of the
removal actions taken in residential areas and at HAAs depends on the prevention of earth-moving
activity that could disturb the surface layer of clean soil thereby exposing elevated
concentrations of contaminants at depth.

Based on the Phase II removal site assessment sampling (April 1995 to July 1995), EPA
began removal actions at certain residential properties on the Site. The action memorandum
authorizing this additional removal response action for residential areas on the Site was issued
on March 21, 1996. The EPA selected a cleanup level for lead in soil of 500 ppm for the removal
response action at the residential areas. This cleanup level was determined by EPA to be
protective of human health. This cleanup level was based upon EPA's Integrated Exposure Uptake
Biokinetic (IEUBK) model for lead in young children utilizing site-specific sampling information
obtained for the preparation of the BHHRA and also upon EPA Region 6 experience with large area
lead cleanups.

As part of Phase II sampling, a total of 2,055 residential homes in Picher, Cardin,
Quapaw, Commerce, and North Miami were evaluated. Approximately 65 percent of these homes had
concentrations of lead, in at least one part of the yard, at or above 500 ppm.

The EPA Emergency Response Team began response activities at the residential homes on June
24, 1996, and resumed response activities at the HAAs following a response action shutdown
during the winter of 1995/1996. Approximately 300 residential homes are being addressed during
the Phase II removal response activities (just as Phase II sampling took place in Site
residential areas, Phase II removal activities address contamination in Site residential areas).
The homes included in the Phase II removal response meet the following conditions:

(1) Homes with children less than 72 months of age who have blood lead levels at or
exceeding 10 ug/dL, and where soil lead concentrations have been determined to be
the significant contributors to elevated blood lead levels; and,

(2) Homes with soil lead concentrations greater than or egual to 1,500 ppm lead.

The response actions being conducted on these properties under Phase II of the removal
response consist primarily of excavation of lead-contaminated soil, backfilling excavated areas
with clean topsoil, and revegetating the backfilled areas with grass sod or seed.

Under the Phase II removal response, excavations at residential homes are being conducted
in 6 inch lifts until confirmation samples show concentrations less than 500 opm lead. The
maximum depth of excavation is 18 inches. That is, if samples reveal residential soil that is
contaminated with lead concentrations which er eed 500 ppm for an area (e.g., front yard,
backyard, driveway, etc.) of the yard, then six inches of soil are removed for each area of the
yard exceeding 500 ppm. The remaining soil in each excavated area is retested in place. This
process is continued until soil is found in place which has concentrations of lead which do not
exceed 500 ppm, or else 18 inches of soil depth is reached, whichever is sooner. If at 18
inches the samples indicate soil lead concentrations greater than or egual to 500 ppm, then a
barrier (e.g., orange construction fence material) is placed in the excavated area prior to
backfilling at that location to warn of existing contamination below that level.

Under the Phase II removal response, EPA is restoring the residential properties to as
close to pre-removal conditions as is practicable. All shrubbery removed during the course of
the response is being replaced according to agreements made between EPA and the individual

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property owners. Initially EPA waters the grass or seed which EPA places on the excavated
areas. After the initial watering, however, EPA does not intend to provide maintenance
including watering of the vegetative cover.

Under the Phase II removal response, the materials removed from the residential areas of
the Site are being disposed of on a dry contaminated area which once contained a mill pond
located between Picher and Commerce on County Road E40 near the location of the old Eagle-Picher
Central Mill. Access to the property is being controlled by a barbed wire fence and gate. A
sign is posted on the gate. The material is being spread over the former mill pond area.
Following the completion of the EPA response actions in the area, the property will be turfed.

The EPA is spraying excavation sites with water for dust suppression during excavation of
the contaminated soil. Dump trucks used to excavate contaminated soil are equipped with covers
to prevent dust from blowing out of the trucks. To assure that the dust suppression activities
are adequate to protect residents and workers, EPA is conducting an extensive air monitoring
program. The program consists of real time dust monitoring as well as air sampling. "Real time"
monitoring means that EPA does not have to wait to get the results of its air monitoring, but
instead the monitoring equipment keeps EPA informed of the concentration levels of airborne
contaminants at all times. In this manner, EPA is made aware of any airborne releases as they
occur.

VI. SUMMARY OF SITE RISKS

An evaluation of potential risks to human health from Site contaminants for the
residential areas of the Site was conducted during the RI and is detailed in the BHHRA. Because
the scope of the RI was limited to the residential areas, only residential exposure scenarios
were considered for evaluation. Current and potential future residential exposure conditions in
the Study Area are expected to be essentially the same; therefore, a separate exposure scenario
for future conditions was not evaluated. The BHHRA identified lead as the only Site-related
chemical of concern, and identified oral ingestion as the only significant exposure route or
pathway. An exposure route or pathway is the way in which contaminants may enter a human being
(e.g, inhalation, oral ingestion, and absorption through the skin). Cadmium and zinc are also
Site-related chemicals, but the concentrations in the different media (soil, air, drinking
water, etc.) for cadmium or zinc were not high enough to exceed acceptable exposure levels as
systemic toxicants or as carcinogens. The BHHRA demonstrated that the elevated concentrations
of lead in soil found at many residences at the Site pose a significant health risk to young
children living at those residences (or to those children who may live at those residences in
the future). Young children (six-years old and younger) who now play (or children six-years-old
and younger who may play in the future) in the residential areas on the Site may be exposed to
lead through incidental ingestion of lead-contaminated soil during normal hand-to-mouth activity
during play, and this lead may pose an imminent and substantial endangerment to the health of
such children. In addition, lead-contaminated soil may be tracked from residential yard soil
into the homes of children where it may be ingested during play or at mealtime, and this lead
may pose an imminent and substantial endangerment to the health of such children. See BHHRA;
and see Centers for Disease Control (CDC) "Preventing Lead Poisoning in Young Children" (October
1991) at pages 20 and 71.

As part of the Feasibility Study process, EPA selects preliminary remediation goals
(PRGs). The PRGs are concentrations of contaminants for each exposure pathway that are believed
to provide adequate protection of human health and the environment based on preliminary site
information. The PRGs are developed on the basis of chemical-specific applicable or relevant
and appropriate requirements (ARARs) (see the Section of this document entitled "'Compliance
with ARARs" for an explanation of ARARs) when available, other available information, and
site-specific risk-related factors. As explained in this document, no ARARs were available for

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the establishment of a PRG for lead-contaminated soil at the Site; consequently, the PRG was
based on the BHHRA, lead-risk computer modeling, and on EPA Region 6's experience with other
soil lead remediation sites [see Section 1.0 (Introduction) of the Feasibility Study Report for
a complete explanation of the PRG, and an explanation of the manner in which the PRG was
selected].

A concentration of lead in the blood of 10 ug/dL or greater for a young child is
considered elevated by the Centers for Disease Control (CDC, October, 1991). In developing a
PRG for CERCLA sites with soil lead contamination in residential areas, EPA recommends that soil
lead cleanup levels be determined so that a typical child or group of children exposed to lead
at the PRG would have an estimated risk of no more than 5 percent of exceeding a blood lead
level of 10 ug/dL (hereinafter this 5 percent risk is referred to as the 5 percent benchmark).
One of the methods which EPA uses to estimate the risk which lead at a given site poses to
children is the Integrated Exposure Uptake Biokinetic (IEUBK) model for lead (see Revised
Interim Soil Lead Guidance for CERCLA Sites and RCRA Corrective Action Facilities, OSWER
Directive No. 9355.4-12 (July 14, 1994) at p. 10; see also Guidance Manual for the Integrated
Uptake Biokinetic Model for Lead in Children, OSWER Directive No. 9285.7-15-1 (February 1994)1.
The IEUBK Model is designed to model exposure from lead in air, water, soil, dust, diet, and
paint and other sources with pharmacokinetic modeling to predict blood lead levels in children 6
months to 7 years old.

When EPA was deciding what method to use to estimate the risk that lead may pose to the
residential population at the Site, EPA considered the following methods: slope studies, direct
blood-lead measurements, and IEUBK modeling. However, EPA decided that the IEUBK model was the
best method for determining the risk posed by lead at the Site. Slope studies are studies of
empirical correlations between lead in environmental media and blood lead. A slope factor
derived from a slope study is the relationship of the expected increase in blood lead level to a
certain increase in lead in an environmental media (e.g., soil). Unlike the IEUBK model, slope
studies are difficult to generalize to situations beyond those where the data were specifically
collected. Also, unlike the IEUBK model, "biological and physical differences between sites and
study populations cannot be incorporated explicitly and quantitatively into regression slope
factors from different studies" [see Guidance Manual for the Integrated Uptake Biokinetic Model
for Lead in Children, OSWER Directive No. 9285.7-15-1 (February 1994) page 1-61. That is, slope
studies do not explicitly include factors that influence lead uptake and behavior in the body
(e.g., ingestion rate, absorption through the gut, etc.). Slope studies lack the flexibility of
the IEUBK model. That is, slope studies are limited in their ability to estimate the effects of
alternate lead abatement methods with different exposure pathways and different lead sources
known to exist at the Site. Direct blood lead measurements are primarily a "snapshot" of
current risks, which may have been influenced by health education activities at the Site, and
are not a prediction of long-term risk conditions. For the Tar Creek Superfund Site risk
evaluations, the IEUBK was considered the best scientific approach for assessing lead risk for
the BHHRA, for predicting potential long-term blood lead levels for children, and for supporting
the establishment of remediation goals.

Based on the results of running the IEUBK Model for the Study Group residences, the BHHRA
predicted that children living in 79 of the Study Group's 100 homes had a greater than 5
percent risk of blood lead levels exceeding 10 ug/dL. That is, the risk to children living in
those Study Group homes was greater than EPA's 5 percent benchmark. Overall risk for the Study
Group (an estimate of community risk) was calculated by mathematically averaging the
probabilities of exceeding the 10 ug/dL blood lead level for each home (assuming one
hypothetical child per home). The overall risk for the Study Group was 21.6 percent, which is
substantially greater than EPA's 5 percent benchmark. The estimated probability of a child
having blood lead levels which exceed 10 ug/dL in the Reference Area (i.e., Afton) is less than
the 5 percent benchmark. The BHHRA for the Site indicates that the percentage of children at the

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Site exposed to unsafe levels of Site-related lead contamination in residential areas is much
greater than EPA's 5 percent benchmark for risk management of lead poisoning.

       The BHHRA also showed that soil lead concentrations exceed the PRG of 500 ppm (see the
Section of this document entitled "Remediation Goals" for an explanation of the basis of the 500
ppm PRG for lead in soil)  in 77 percent of the yards of Study Group homes in Picher, and in 45
percent of the yards of the homes in the Study Area.  The EPA generally recommends remedial
action when the PRG is exceeded  [see Revised Interim Soil Lead Guidance for CERCLA Sites and
RCRA Corrective Action Facilities,  OSWER Directive No. 9355.4-12 (July 14, 1994) at p.10].

       The BHHRA indicated that,  in most cases,  the elevated blood lead levels predicted by the
IEUBK model are due primarily to elevated concentrations of lead in outdoor soil, although
indoor dust also contributes significantly in many cases  [of course, a primary source of indoor
dust may be contaminated outdoor soil tracked into the home (CDC, October 1991, at p. 71)].
Young children were the segment of the population considered to be at greatest risk from
exposure to lead according to the BHHRA findings.  The BHHRA also indicated that elevated levels
of lead in indoor dust found in many homes on the Site pose a significant health risk to
children living in those homes (or who may live in those homes in the future).  The BHHRA
indicated that the residential yard soil was likely to be a significant source of lead in indoor
dust in these homes.

       In an independent blood lead survey conducted by the Oklahoma State Department of Health
(OSDH)  in October 1995, in Picher,  Oklahoma, OSDH found a percentage of young children with
elevated blood lead levels (10 ug/dL or greater)  similar to the percentage predicted in EPA's
BHHRA for the Picher Study Group (the OSDH survey was an actual measurement of lead in
children's blood and not a prediction).   Later surveys conducted in August 1996 and September
1996, on behalf of certain mining companies, which once operated at the Site, found that 38.3
percent (31 of 81) of the children tested in Picher had blood lead concentrations exceeding 10
ug/dL,  that 62.5 percent (10 of 16)  of the children tested in Cardin had blood lead
concentrations exceeding 10 ug/dL,  and that 13.4 percent  (9 of 67)  of the children tested in
Quapaw had blood lead levels which exceeded 10 ug/dL.

       In order to develop response action alternatives to address the lead contamination, EPA
conducted a Feasibility Study (FS).    The FS developed and evaluated appropriate remedial action
alternatives such that relevant information concerning the remedial action options to address
the contamination would be presented to EPA decision-makers and an appropriate remedy selected.
Once the FS was complete,  EPA prepared a Proposed Plan which identified the alternative that,
based on the FS, best met the reguirements of 40 CFR ° 300.430(f)(1), and EPA presented that
Proposed Plan for public comment. After evaluating comments received on the Proposed Plan during
the public comment period,  EPA prepared this ROD which describes the remedial alternative which
EPA has selected to address the contamination at the residential areas on the Site.

IEUBK Model Default Parameters

       The Geometric Standard Deviation (GSD)  is an expression of the variability of a  set of
data (e.g., blood lead levels).   Bioavailability with regard to lead exposure is an expression
of the extent to which lead that enters the body is taken up by the blood.  Comments from the
public regarding EPA's removal actions have included statements saying that GSD and
bioavailability values that are lower than the IEUBK model default values should be used by EPA
in selecting its remedial action for the residential areas in Operable Unit 2.  Lowering either
of these values would tend to raise the remediation goals based on IEUBK modeling.  The
following enumerated paragraphs discuss EPA's reasons for not lowering the GSD and the
bicavailability values:

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1. Bioavailability - The EPA has determined that lead oxides and lead carbonates are
major forms of lead in the tailings in the Tri-State Mining District based on results
of studies on samples taken from Tri-State Mining District tailings and
tailings-contaminated materials by EPA Region 8 in 1996, and by the University of
Colorado, Department of Geological Sciences in 1996. More soluble forms of lead such
as the lead oxides and lead carbonates found on the Site are relatively more
bioavailable than less soluble forms of lead such as galena (PbS) (EPA, February
1994). Therefore, since the forms of lead found on the Site are of the more
bioavailable type of lead, there was no reason for EPA to lower the bioavailability
parameter in the IEUBK model below the 30 percent default value in the development of
the BHHRA.

2. GSD - Estimates of GSD for lead mining sites have increased toward larger GSD values
as the geometric mean blood levels have decreased (EPA, February 1994). That is, as
average blood lead levels have decreased in the U.S. (this decrease in national
average blood lead levels has been a trend in recent years), the GSD values (as an
expression of degree of mathematical spread about the average blood lead level) at
mining sites have tended to increase. Therefore, since the trend in GSD values is
upward at sites like the Tar Creek Superfund Site, there was no basis to lower the
GSD from the IEUBK model default value of 1.6 in the development of the BHHRA.

Ecological Risks

The residential areas at the Site are not associated with exposed ecological communities.
The residential areas do not support wildlife or wild species of flora. Without receptors of
ecological concern, the residential area represents an incomplete ecological risk pathway. That
is, there is no identified exposure pathway along which the contaminants of concern could travel
to reach wild flora or fauna, and cause a detrimental effect. Because there is no relevant
completed exposure pathway associated with the residential properties, an evaluation of
ecological risk at the residential areas of the Site was not considered appropriate.

Remediation Goals

As explained above, remedial action objectives are the more general description of what
the remedial action will accomplish. Remediation goals are a subset of remedial action
objectives, and consist of medium-specific or operable unit-specific chemical concentrations
that are protective of human health and the environment and serve as goals for the remedial
action.

The BHHRA identified lead-contaminated soil as the medium which posed the greatest threat
to human health on the Site. The EPA recommends that, for soil lead, a remediation goal be
selected such that a typical child or group of children exposed to the soil in guestion would
have an estimated risk of no more than 5 percent of exceeding a blood lead concentration of 10
ug/dL (EPA, July 1994). The EPA's preliminary remediation goal (PRG) was set at a level which
should meet the 5 percent benchmark; therefore, EPA has decided to make the remediation goal for
soil cleanup the same as the PRG--500 parts lead per million parts soil (ppm). The remediation
goal and the PRG are based on the BHHRA, on IEUBK modeling, and on Region 6 experience with
other soil lead remediation sites. The PRG for lead in soil of 50C ppm was derived from
recommendations in the document entitled "Preliminary Remediation Goals for the Tar Creek
Superfund Site" (September 1996)(hereinafter PRG Report). The PRG Report is based upon sampling
data generated for the Baseline Human Health Risk Assessment (August 1996). The PRG Report
develops estimated cleanup goals using a statistical and an empirical approach. Both analyses
are based upon EPA's IEUBK model. Under the two analyses undertaken in the PRG Report, the
cleanup goals estimated for the Site ranged from 456 ppm (empirical estimate) to 500 ppm

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 (statistical estimate).   A PRG/remediation goal of 500 ppm for lead-contaminated soil in
residential areas was selected based on the following reasons:

       (1)     EPA Region 6 has extensive experience cleaning up lead- contaminated soil at other
              sites and  cleanup levels for residential areas have generally been selected at or
              near 500 ppm.

       (2)     The additional risk reduction to be achieved by selecting 456 ppm versus 500 ppm is
              insignificant and does not warrant a departure from established successful past
              Region 6 practice.

       (3)     The incremental cost difference between a remedial action which utilizes 456 ppm as
              a cleanup  level and a remedial action which utilizes 500 ppm as a cleanup level is
              not proportional to the difference in effectiveness.

       In short, EPA has adopted 500 ppm, the PRG which EPA developed for FS purposes, as the
final remediation goal for soil lead.  This 500 ppm remediation goal should not be confused with
the "action level.  " In this ROD, the term "action level" means  a contaminant concentration in
the environment  (e.g., surface soil in residential areas) high enough to warrant or trigger an
engineering response  (e.g., excavation or capping).  The remediation goal  (500 ppm) is the same
for all remedial action alternatives  (RAAs) discussed in this ROD, regardless of the action
level.

       For example, the  800 ppm action level proposed for Alternative 3 is higher than the
remediation goal  (500 ppm).  Under Alternative 3, the 800 ppm action level is the level at which
excavation would be triggered.  However, since excavation to 800  ppm does not reach the
remediation goal, residual risk remains, and additional measures  must be taken.  Under
Alternative 3, the additional measures intended to address residual risk consist of Community
Protective Measures (CPMs)  (e.g., health education, house cleaning and health monitoring).  The
CPMs are intended to address the residual risk posed by any soil  which may remain in place with
lead concentrations between 500 and 800 ppm. An 800 ppm excavation action level is not
protective without measures to address the residual risk between  500 ppm and 800 ppm; however,
an 800 ppm action level with perpetual CPMs to address the residual risk may be protective if
the CPMs can be maintained forever  (or at least as long as the contamination above the
remediation goal remains).

VII.   DESCRIPTION OF ALTERNATIVES

Common Elements in All Alternatives

       To supplement active engineering measures, some institutional controls will be reguired
under all the remedial action alternatives in order to address Site contamination.  To put some
of these institutional controls into effect, the authority of other governmental entities may be
reguired (e.g., zoning restrictions may reguire municipal authority, lease restrictions may
reguire DOI authority);  accordingly, they are  contingent on the  cooperation of those
authorities.  These institutional controls may include the following items:  (1) restrictions and
management controls on unsafe uses of mine tailings;  (2) restrictions and management controls on
activities that would cause recontamination at remediated properties;  (3) restrictions and
management controls on activities this would contaminate clean Site property with mine tailings;
 (4) restrictions and management controls intended to prevent future exposure of children to
unacceptable levels of lead in the soil at new residential developments that are located in
areas with high lead levels in soil  (in some cases these controls may be implemented at existing
residential developments);  (5) restrictions and management controls on building and construction
activities in order to prevent building and construction practices that would increase exposure

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to lead-contaminated soil;  (6) restrictions and management controls on access to contaminated
property through physical barriers  (e.g., fencing) or notices  (e.g., warning signs);  (7) public
health and environmental ordinances and controls related to lead exposure and management of mine
tailings;  (8) placing notices in property deeds regarding contamination;  (9) sampling and
analysis of lead sources; (10) blood lead monitoring; (11) health education; and,  (12)
lead-contaminated dust reduction activities.  All of the enumerated items listed above in this
paragraph would be implemented under Alternatives 2 through 8.  Items 9 through 12 would be
implemented on the largest scale under Alternative 3, but may be used under the other
alternatives.  At residences with children at which lead-contaminated soil was not excavated
(e.g., where access for remedial action was not granted), health education, lead-contaminated
dust reduction activities, and blood lead monitoring may be utilized.  The restrictions related
to mining waste in enumerated items 1 through 6 will generally be implemented through the
appropriate authority for the property in guestion (i.e., Bureau of Indian Affairs for Indian
lands under its management,  Ottawa County Reclamation Authority for properties under its
control, local governmental bodies for properties within their jurisdiction, etc.).  The
supplementary institutional controls will be selected from the preceding list; however, since
there are hundreds of residential properties to be remediated, and since each property is unigue
in certain respects, the supplementary institutional controls to be used at a given property
cannot be determined until the Remedial Action phase, when each property is separately
remediated.  However, many of the institutional controls such as community-wide health
education, community-wide lead-contaminated dust reduction activities, and community-wide blood
lead monitoring, are considered appropriate for community-wide application in residential areas
throughout Ottawa County.

       Moreover, soil excavation to a maximum depth of 18-inches may not be the most appropriate
response action at certain residential properties, or at portions of a residential property, due
to physical features, use, or other constraints.  Such situations cannot be evaluated until the
remedial action phase, when each property is separately remediated.  In such cases measures
selected from the following list may be used: (1) capping of contaminated areas with clean soil;
(2) vegetating poorly vegetated or unvegetated areas; (3) capping contaminated areas with base
coarse material and/or paving; and  (4) excavating to depths other than 18-inches.

       In addition,  certain sources of lead contamination, which are near or located within the
residential areas to be remediated, may have the potential to recontaminate remediated areas.
For example, certain residences may be near sources  (e.g., chat piles) of lead-contaminated
waste material; accordingly, rainwater runoff, wind-blown dust, or other  mechanisms that
transport contaminated material from the piles may recontaminate remediated yards.  Therefore,
the following measures may be taken at source areas to prevent recontamination or to minimize
recontamination potential of residential areas:   (1) vegetating poorly vegetated or unvegetated
areas;  (2) capping with soil; (3) capping with base coarse material or paving  (4) applying dust
suppressants or other dust control measures;  (5) controlling drainage;  (6) consolidation of
source materials; (7) containment of source materials; and (8) abating lead sources to prevent
releases into the environment that would recontaminate remediated areas.  Due to the unigue
nature of each situation in which recontamination may occur,  it cannot be determined in advance
which measures will be used; therefore, recontamination prevention measures will be selected
from the preceding list on a case-by-case basis during the Remedial Action phase.

       During the Remedial Action phase,  land owners may decide to permanently change land use,
for certain residential properties which are the subject of the Remedial Action, to commercial
or other non-residential use.  In such cases, remediation of the property in guestion would be
deferred until the remediation can be incorporated into a CERCLA response action addressing
contaminated non-residential properties on the Site.

       The establishment of a permanent long-term on-Site disposal area primarily for the purpose

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of disposing of lead-contaminated soil excavated during response actions, but also for disposing
of contaminated soil from areas of new construction will be supported.

In the event that the EPA is unable to dispose of excavated materials on-site, off-site
disposal will be reguired. However, since the materials are not a hazardous wastes under the
Resource Conservation and Recovery Act (RCRA) , EPA does not consider RCRA hazardous waste
management reguirements to be applicable, relevant or appropriate, including without limitation
the waste analysis reguirements found at 40 CFR °° 261.20 and 261.30, the RCRA manifesting
reguirements found at 40 CFR ° 262.20, and the RCRA packaging and labeling reguirements found at
40 CFR ° 262.30. Since the remedy involves no on-site storage of hazardous wastes, storage
reguirements found at 40 CFR Part 265 are not applicable, relevant or appropriate. All off-site
transportation of hazardous waste (if any) will be performed in conformance with applicable U.S.
Department of Transportation (USDOT) reguirements. Any off-site disposal of CERCLA waste (if
any) will be in conformance with EPA's procedures for planning and implementing off-site
response action, 40 CFR ° 300.440.

For certain residential properties, to be identified during the Remedial Action phase,
where the recontamination potential is significant or where restoration is not practicable and
where the residents move to alternate properties at the Site, the alternate properties may be
prepared for residential use by performing non- structural improvements, similar to the
excavation and restoration activities provided for the other residential properties at the Site.
The EPA would not provide the alternative properties or houses, nor would EPA move or
temporarily house the residents.

Alternatives (Alternatives 2, 3, 5, 6, 7, and 8) propose excavation, which would reguire
short-term dust control to protect the community and the workers. Additionally, as part of all
remedial alternatives which call for excavation, the workers would be reguired to use personal
protective eguipment to ensure their protection during the remedial action, especially during
excavation activities.

Significant changes and additions between the ROD and the Proposed Plan are described in
the Section of this ROD entitled "Documentation of Significant Changes. "All of the significant
changes and additions described in that section would have been part of any alternative selected
except for the no-action alternative.

Remedial Action Alternatives

Seven alternatives, in addition to the no-action alternative, were developed in the FS to
meet the RAO. The EPA regulations reguire the inclusion of a no-action alternative. A listing
of the alternatives and the associated costs are presented in Table 2. The alternatives were
developed to specifically address the mining waste contamination in the residential areas of the
Site.
In the descriptions of the response action alternatives which appear below, the following
terms are used:

Capping - Capping an area means covering it with uncontaminated material generally clay
and soil.

Vegetating - Vegetating means establishing or planting vegetation (generally grass) on an
area. In order to control erosion and to create an aesthetically appealing cleanup
area, EPA freguently utilizes vegetation or revegetation for areas which have been
remediated.

Solidification and stabilization - Solidification and stabilization means mixing

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contaminated material with a binding agent such as Portland cement. This helps
ensure that the contaminant stays in place and does not migrate due to rainwater
runoff, ground water percolation, or wind erosion.

Backfilling - Backfilling means putting clean soil back in areas where the contaminated
soil has been excavated.

Geotextile marker - A geotextile marker is a type of plastic material (usually a fabric or
wide mesh safety fencing material) that is put in the bottom of an excavated area
before it is backfilled. The purpose of the marker is to warn those who excavate
the backfilled area in the future that contamination lies below the barrier.

Alternative 1 (No Action): The no-action alternative provides a baseline against which
other alternatives can be evaluated. Under this alternative, no remedial action will be taken.
A summary of estimated costs, estimated guantities of materials to be excavated, and estimated
time of implementation is as follows:

Capital Costs: $0
Present Worth: $0
Annual O&M Costs: $0
Excavation volume: None
Implementation time: None

Alternative 2 (Soil Excavation with a 500 ppm Action Level) consists of the following:

a. Contaminated surface soil will be excavated until there is no lead at concentrations
above the action level (which is the same as the remediation goal) to a maximum depth
of 18 inches.

b. Areas will be backfilled with clean material. The type of backfill will depend on
the use of the areas. Yard areas will be backfilled with topsoil and revegetated.
Driveways and other traffic areas will be backfilled with road base material (e.g,
gravel). Yard areas which are affected by the remedial action (e.g., excavated, or
used as staging areas) will be landscaped in order to, if practicable, return the
areas to the condition which they were in prior to the remedial action. Trees,
shrubs and plants will be replaced with commercially available eguivalent or similar
items. Fences or other structures which must be moved will be removed and placed
back at or near their original locations, or demolished and replaced with
commercially available eguivalent or similar items.

c. If soil lead concentrations exceed the action level at 18 inches, a marker consisting
of a geotextile fabric or other suitable material will be placed in the excavated
area prior to backfilling with clean fill.

d. All excavated contaminated soil will be disposed of on-Site in dry rural
mining-waste-contaminated areas, such as the former locations of tailings ponds.
These areas are mining waste disposal areas that are already highly contaminated with
lead. These areas are located away from heavily populated areas.

e. The soil excavated from the residential areas will be spread over the disposal area
to blend into the contours of the surrounding land. Upon final completion of the
disposal of contaminated soil at the disposal area, the disposal area will be
vegetated with grass. The disposal area will also be capped with clean soil prior to
vegetating, unless the surface of the disposal area already has soil lead

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concentrations less than 500 ppm. Contaminated soil excavated from the yards will
generally be removed in 6-inch layers, and, consequently, this excavated soil usually
contains some soil with lead concentrations less than 500 ppm. As the excavated soil
is handled, incidental mixing will generally occur, and generally soil lead
concentrations greater that 500 ppm will be reduced due to dilution from this mixing.
As a result of mixing during normal handling of excavated soil, soil contamination in
many parts of the disposal area may be lower than the remediation goal; conseguently,
no clean soil cap will be needed in these parts of the disposal area. The on-Site
areas that will be used for disposal will actually be environmentally enhanced by the
disposal. The soil that is being placed in the disposal areas is actually less
contaminated than the mining waste already present in the disposal areas. Also,
establishing vegetative cover on the disposal areas is an enhancement since these dry
mining areas typically do not support vegetation and typically are sources for
further spreading of contamination and for wind and surface water erosion. The
eroded mining waste is transported by wind and surface water and redeposited in other
areas, including residential areas. The establishment of vegetative cover will
reduce dust generation and erosion at the disposal areas.

f. Summary of estimated costs, estimated quantities of materials to be excavated, and
estimated time of implementation:

Capital Costs: $26,764,400
Present Worth: $24,478,219
Annual O&M Costs: $60,000
Excavation volume: 364,400 cubic yards
Implementation time: 6 years

Alternative 3 (Soil Excavation with 800 ppm Action Level along with Community Protective
Measures) consists of excavation, backfilling, revegetation, and disposal in the same manner and
to the same depth as Alternative 2. That is, all the steps described above for Alternative 2
will be taken, except that the action level would be 800 ppm which means that some contamination
above the remediation goal (500 ppm) may remain in place. To address the residual risk
resulting from the contaminated surface soil left in place with lead concentrations between 500
ppm and 900 ppm, CPMs would be perpetually implemented. CPMs would include the following
principal provisions:

a. Annual blood lead screening of the children living in residences with residual risks.
b. Sampling of lead sources for characterization and monitoring purposes at individual
residences with residual risks.
c. Individual follow-up lead exposure reduction counseling.
d. Community lead poisoning and prevention health education.
e. "Super cleaning" using high efficiency particulate vacuum cleaners (HEPA VAC) to
reduce the levels of dust in residences with residual risks.
f. Summary of estimated costs, estimated quantities of materials to be excavated, and
estimated time of implementation:

Capital Costs: $12,764,800
Present Worth: $17,194,533
Annual O&M Costs: $360,000
Excavation volume: 171,900 cubic yards
Implementation time: 3 years (with perpetual CPMs)

Alternative 4 (Capping In-Place with 500 ppm Action Level) consists of in-place capping
for containment if residential soil exhibiting lead concentrations greater than or equal to 500

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ppm.  Residential soil would be covered in place with twelve to twenty-four inches of clean soil
or gravel.  Remediated areas would be regraded and revegetated, and landscaped and repaired as
described under Alternative 2.  A summary of estimated costs, estimated guantities of materials
to be excavated, and estimated time of implementation is as follows:

              Capital Costs:   $14,360,800
              Present Worth:   $14,156,949
              Annual O&M Costs:   $60,000
              Excavation volume:   None
              Implementation time:   3 years

       Alternative 5 (Soil Excavation with 500 PPM Action Level and with Solidification/
Stabilization Treatment) consists of excavation of residential yard soil exhibiting lead
concentrations greater than or egual to 500 ppm, and solidification/stabilization treatment of
the excavated soil.  The excavation, backfilling, revegetation, landscaping, repair and disposal
components of Alternative 5 would be the same as in Alternative 2.   Treatment facilities would
be established at the Site for treatment of contaminated soil prior to permanent disposal.
Treatment would incorporate the most feasible technologies available to solidify or stabilize
lead contaminants while minimizing volume increases.  Traditional solidification agents such as
pozzolanics would be considered in conjunction with proprietary chemicals based on treatment
results and costs.  A summary of estimated costs, estimated guantities of materials to be
excavated, and estimated time of implementation is as follows:

              Capital Costs:   $55,694,400
              Present Worth:   $50,136,522
              Annual O&M Costs:   $60,000
              Excavation volume:   364,400 cubic yards
              Implementation time:   6 years

       Alternative 6 (Soil Excavation with 500 ppm Action Level and with Washing/Leaching
Treatment) consists of excavation of residential soil exhibiting lead concentrations greater
than 500 ppm, and washing/leaching treatment of the excavated soil.  The excavation,
backfilling, revegetation, landscaping and repair components would be the same as in Alternative
2.  Treatment facilities would be established at the Site. Soil washing/leaching would consist
of the following:  1) the addition of water and chemical additives such as surfactants, acids,
bases, and chelates to the soil in order to produce a slurry feed;  2)  injection of the slurry
into separators and other eguipment to create mechanical and fluid sheer stress; and 3) removal
of contaminated silts and clays from granular soil particles.  That is, in the third step
described in the previous sentence, the fine-grained contaminated particles would be removed by
washing the soil through fine screens, and the contaminants in the coarser soil fraction would
be removed by flowing wash water through the soil.  Both physical agitation and washing
additives would be used to improve removal efficiency.  This treatment technology would achieve
the following three output streams:  1) coarse clean fraction - to be disposed on-Site without
capping, 2) contaminated fine fraction - to be disposed of on-Site in dry mining waste areas
with subseguent capping, and 3)  process wash water to be treated to remove solubilized heavy
metal fractions prior to return to process or discharge.  Initial physical screening to remove
coarse rock and debris may also be reguired prior to soil washing/leaching in order to ensure
that treatment results are effective.  A summary of estimated costs, estimated guantities of
materials to be excavated, and estimated time of implementation is as follows:

              Capital Costs:   $74,663,600
              Present Worth:   $67,004,294
              Annual O&M Costs:   $60,000
              Excavation volume:   364,400 cubic yards

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Implementation time: 6 years

Alternative 7 (Sail Excavation with 500 ppm Action Level and with Lead-Reduction Chemical
Treatment) consists of excavation of lead-contaminated soil exhibiting lead concentrations
greater than or egual to 500 ppm, and lead-reduction chemical treatment of the excavated soil.
The excavation, backfilling, revegetation, landscaping, repair and disposal components would be
the same as in Alternative 2. Treatment facilities would be established at the Site for
treatment of contaminated soil prior to permanent disposal. Excavated soil would be treated
with chemical additives to reduce the valence state of the lead contaminants, thereby reducing
their mobility, bioavailability and exposure risks. Reducing the valence state means that the
lead gains negative electrical charges. A summary of estimated costs, estimated guantities of
materials to be excavated, and estimated time of implementation is as follows:

Capital Costs: $36,413,600
Present Worth: $33,059,038
Annual O&M Costs: $60,000
Excavation volume: 364,400 cubic yards
Implementation time: 6 years

Alternative 8 (Soil Excavation with 500 ppm. Action Level and with Electrokinetic
Remediation) consists of excavation of residential soil exhibiting soil lead concentrations
which exceed 500 ppm, and electrokinetic remediation treatment of the excavated soil. The
excavation, backfilling, revegetation, landscaping, repair and disposal components would be the
same as in Alternative 2. Treatment facilities would be established at the Site for treatment
of contaminated soil prior to permanent disposal. The removal of lead in contaminants in the
excavated soil would be achieved by a combination of electrodes and managed recirculating
electrolytes to desorb, migrate and recover ionic lead contaminants. In other words, the
contaminated material would be placed into solution in a container with positive and negative
electrically charged poles (electrodes). Lead being positively charged would be repelled from
the positively charged electrode, and would be drawn to the negatively charged electrode where
it would be removed from the solution. A summary of estimated costs, estimated guantities of
materials to be excavated, and estimated time of implementation is as follows:

Capital Costs: $48,265,000
Present Worth: $42,763,795
Annual O&M Costs: $0
Excavation volume: 364,400 cubic yards
Implementation time: 6 years

Basis of Maximum 18 inch Surface Soil Excavation Depth

The excavation depth of 18 inches is based on the maximum depth reguired to reach a soil
lead concentration of 500 ppm and the low uptake of lead in plants at the Site. Field
observations by EPA during the removals at the Site have indicated that with few exceptions 18
inches is the maximum excavation depth reguired to remove soil with a lead concentration greater
than 500 ppm. Also, based on samples of produce taken at the Site, the uptake of lead from
vegetable gardens at the Site is low. For vegetable gardens at the Site, 18 inches of clean
soil would reduce lead uptake in plants to insignificant levels.

VIII. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES

The selection of a remedial action alternative is a two-step process. First, EPA, in
conjunction with ODEQ and the Indian Tribes involved with the Site, reviewed the results of the
RI/FS to identify the preferred alternative (in this case Alternative 2). The EPA then

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presented the preferred alternative to the public for review and comment, along with supporting
information and analysis, in the Proposed Plan. Second,  EPA reviewed the public comments, and
consulted with ODEQ and the Indian Tribes involved in order to evaluate whether the preferred
plan was still the most appropriate remedial action for the residential areas of the Site and
EPA made the final remedy selection decision.

       The EPA identified the preferred alternative and the final remedy selection based on an
evaluation of the major tradeoffs among the remedial alternatives in terms of the nine
evaluation criteria listed at 40 CFR °300.430(e) (9) (iii) .   In order to be eligible for
selection, remedial alternatives must meet the two threshold criteria from among the nine
criteria.  To meet these two criteria,  the remedial alternatives must be protective of human
health and the environment and comply with ARARs  (or justify a waiver).

       Among those remedial alternatives that met the threshold criteria, EPA balanced the
tradeoffs among the alternatives with respect to the balancing criteria which are long-term
effectiveness and permanence, reduction of toxicity,  mobility or volume through treatment,
short-term effectiveness, implementability and cost.   This analysis is described in the Section
of this ROD entitled "Summary of Comparative Analysis of Alternatives."

       After the public comment period on the Proposed Plan concluded,  EPA factored in ODEQ,
Indian Tribe, and community acceptance as modifying criteria.  This process is also discussed in
the Section of this ROD entitled "Summary of Comparative Analysis of Alternatives."  This ROD
memorializes EPA' s decision to select Alternative 2  (Soil Excavation with a 500 ppm Action
Level) as the remedial action to address the contamination in the residential areas on the Site.

Threshold Criteria

Overall Protection of Human Health and the Environment

       This criterion reguires EPA to determine, as a threshold reguirement,  whether each
alternative meets the reguirement that it is protective of human health and the environment.
The overall assessment of protection is based on a composite of factors assessed under the
evaluation criteria, especially long-term effectiveness and permanence, short-term
effectiveness, and compliance with ARARs.

       Alternatives 2,  5, 6,  7,  and 8,  provide protection by excavation of lead-contaminated soil
at or above the health-risk- derived level of 500 ppm to a maximum depth of 18 inches with
complete removal of the excavated soil from the residential areas, followed by backfilling with
clean soil.  Additionally, Alternatives 5, 6, 7, and 8,  provide protection through treatment of
the excavated soil prior to final disposal.  Alternative 3 provides protection by a combination
of excavation and CPMs.  Under Alternative 3, risks associated with lead-contaminated soil with
lead concentrations between the 500 ppm remediation goal and the 800 ppm action level (800 ppm
is not a health-risk-derived  level)  are addressed by CPMs. Alternative 4, capping in-place,
provides protection by installation of a soil and sod barrier between residents and underlying
contaminated materials, thereby removing the contaminated soil from the human exposure pathway.

       Alternative 1 (no action)  would not be protective of human health and the environment,
because it does nothing to address the soil lead contamination which has been determined in the
BHHRA to pose and unacceptable health risk, especially to children.

Compliance With ARARs

       This criterion is used to decide how each alternative meets ARARs, as defined in CERCLA
Section 121, 42 U.S.C.  ° 9621, and as defined in the NCP at 40 CFR ° 300.5.  Compliance is

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judged with respect to chemical-specific, action-specific and location-specific ARARs as well as
appropriate criteria, advisories and guidance. All alternatives meet the ARARs. An evaluation
of ARARs is presented in Table 3 through Table 5 of this ROD. A summary of the evaluation is
provided below:

a. Chemical-specific ARARs - There are no Federal or State ARARs for lead-contaminated
soil. The soil lead remediation goal of 500 ppm that is applicable to all the
alternatives considered was based on the BHHRA, IEUBK modeling, and Region 6
experience at other soil lead remediation sites. The soil lead excavation action
level of 800 ppm, used in Alternative 3, was based on remedial actions by Region 7 to
address soil lead contamination in Joplin, Missouri and Galena, Kansas.

b. Location-specific ARARs - All proposed activities at the Site are compliant with any
location-specific ARARs.

c. Action-specific ARARs - The lead contamination in the soil is primarily from mining
waste (overall the evidence leads to this conclusion) which is a solid waste, but not
a hazardous waste under the Resource Conservation and Recovery Act (RCRA) , because it
is solid waste from the extraction, beneficiation, and proce sing of ores and
minerals, according to 40 CFR ° 261.4(b)(7). Disposal of excavated lead-contaminated
soil will be on-Site within the area of contamination, but away from residential
areas. Dust generation will be controlled during construction to meet relevant and
appropriate Federal and State air guality laws and regulations.

d. To-be-considered (TBCs) - In addition to ARARs, other advisories, criteria, or
guidance that may be useful in developing the remedy were, as appropriate, identified
and considered.

Balancing Criteria

Long-term Effectiveness and Permanence

This criterion of the NCP requires EPA to assess alternatives based on the long-term
effectiveness and permanence they afford, along with the degree of certainty that the
alternative will prove successful. Regarding the Site, the primary focus of this evaluation was
to determine the extent and effectiveness of the controls that may be required to manage the
residual risk posed by treated and/or untreated soil at the Site.

Alternatives 2, 5, 6, 7, and 8, which propose a 500 ppm excavation action level would
essentially eliminate exposure risks in residential areas by removing lead-contaminated surface
soil above the health-risk-derived level to a maximum depth of 18 inches. The contaminated soil
would be consolidated and placed in contaminated areas of the Site away from the residential
population. The treatment remedies (Alternative 5, 6, 7, and 8), which propose to treat lead
contaminants after excavation and removal from the yards, would not be significantly more
effective than excavation alone, as called for in Alternative 2, at reducing residential risks
because the Site areas that are proposed for disposal are already highly contaminated, and the
disposal areas are located safely away from residential populations. No significant additional
benefits result from treating the soil before it is placed in these remote and previously
contaminated areas. Alternative 3, which proposes an 800 ppm excavation action level, results
in residual risks. The residual risks are associated with the surface soil with lead
contamination between 500 ppm (the remediation goal) and 800 ppm (the proposed action level
under Alternative 3) that would not be excavated, and the indoor dust resulting from the
contaminated soil remaining in the yards. The residual risks are addressed by Alternative 3
through the implementation of perpetual CPMs. Health education to reduce lead exposure, and

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super cleaning using HEPA VACs to control the levels of indoor lead-contaminated dust would be
major components of the CPMs. Alternative 3, which proposes excavation at or above an 800 ppm
action level, which is not a health risk-based level, is less source protective than the
remedies which excavate using the 500 ppm level. Alternative 3 permanently protects the
residents from the portion of the contaminated soil that is excavated above the 800 ppm lead
action level. However, to protect the residents from the residual risks from surface soil
remaining in place below the 800 ppm action level, Alternative 3 relies on CPMs. CPMs are not
permanent like excavation, and must be continued in perpetuity. There are concerns about the
long-term effectiveness of the CPMs in reducing lead exposure because of the difficulty of
permanently altering human behavior in residential settings at the Site through health
education. It is unlikely that CPMs could be continued in perpetuity. That is, it may be
possible to educate the present generation of children and parents who live in the residential
areas on the Site with regard to lead exposure reduction, but it may not be feasible to
establish a permanent program to educate future generations. Also, CPMs place a greater burden
of responsibility for lead exposure reduction on the residents at the Site as compared to
permanent engineering controls. For example, for Alternative 2 and Alternatives 4 through 8,
normal house cleaning by residents would be adeguate to control indoor dust originating from
outdoor lead-contaminated soil; whereas, for Alternative 3, super cleaning using HEPA VACs would
be reguired for residences where the yard soil was not excavated. Perpetual CPMs would be
reguired, since lead contamination at levels which would pose a health risk would remain in the
residential areas under Alternative 3. Finally, to the degree that residual risk remains to be
addressed by perpetual CPMs, Alternative 3 is inconsistent with the statutory preference for
permanent remedies under CERCLA Section 121, 42 U.S.C. ° 9621.

Residual risks from contaminants above the health-risk- derived level remaining in
residential areas are also a concern with Alternative 4, capping in-place, and Alternative 1
which proposes no action. Alternative 4 which utilizes barriers or covers to prevent direct
human contact with contaminated soil has doubtful long-term effectiveness and is not considered
permanent like excavation because the potential for disruption of the barriers through normal
residential digging activities (e.g., gardening, tree planting, utility trenching, etc.) is
substantial. In addition, there is significant potential for the caps to be disrupted by
erosion which may result from inadeguate maintenance of the vegetative cover in the future since
such maintenance will be up to the individual homeowner or occupant. Such disruptions of the
caps could once again expose children to the lead. Indefinite future monitoring and maintenance
to ensure integrity of covers, and institutional controls to prohibit disturbance of the covers
are not considered practicable for the residential yards at the Site. Due to the difficulty of
maintaining the caps intact in a residential setting, Alternative 4 is considered the least
effective of the engineering remedies over the long-term. In addition, since the final grades
of the covers would typically be higher than the existing residence foundations and adjacent
property grades, existing drainage patterns would be altered and significant drainage problems
would probably be created. The terrain of the residential areas is mostly flat, and residential
drainage problems already exist. The potential for drainage problems to be significantly
worsened by the addition of soil covers is substantial. In short, the capping alternative may
address the problem of direct lead exposure in the short term, but in the long-term, since
maintenance is not assured, the cap is likely to be broken; moreover, capping will create
drainage problems.

Institutional controls include measures such as deed notices, warning signs, and zoning
restrictions against certain excavation activities. Institutional controls would be reguired to
a greater degree as a risk-management component for those alternatives where contaminated
surface soil with lead concentrations above the remediation-goal (500 ppm) remained in the
residential areas. Accordingly, institutional controls would be reguired to a greater degree
for Alternative 4 because, under Alternative 4, lead-contaminated surface soil with lead
concentrations above 500 ppm level is not removed, but is capped in place. Institutional

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controls, primarily CPMs, would also be required to a greater degree for Alternative 3 which
calls for lead-contaminated surface soil with lead concentrations between 500 ppm and 800 ppm to
remain exposed in place within the residential areas.  The CPMS for Alternative 3, would be
required to a much greater degree than for the other alternatives in order to manage residual
risks remaining in residential areas.  These residual risks, under Alternative 3, are associated
with the potential for direct contact with surface soil where the soil was not removed because
lead concentrations were not greater than 800 ppm.  Alternative 2 and Alternatives 4 through 8
do not require the same degree of institutional controls, including the implementation of CPMs,
as Alternative 3 requires in order to be protective.

       In general,  permanence of the remedial action at the Site is greatest for Alternatives 2,
5, 6, 7, and 8 because these alternatives require excavation of lead-contaminated surface soil
to the health-risk-derived action level of 500 ppm, to a maximum depth of 18 inches, followed by
permanent disposal of the excavated soil away from the residential areas.

Short-term Effectiveness

       This criterion addresses the effects of the alternatives during the construction period
until the remedial actions have been completed, and the selected level of protection has been
achieved.  Alternative 4, which proposes immediate containment without lead-contaminated soil
disturbance, is considered the most effective in the short-term, because it has much less
potential to generate lead-contaminated dust, compared to the excavation alternatives.
Implementation of Alternative 1, no action, will not increase or decrease the short-term effects
on human health or the environment.

       All the other alternatives (Alternatives 2, 3, 5,  6,  7,  and 8)  propose excavation,  which
would require short-term dust control to protect the community and the workers.  Additionally,
as part of all remedial alternatives which call for excavation, the workers would be required to
use personal protective equipment to ensure their protection during the remedial action,
especially during excavation activities.

       Under those alternatives which call for treatment of the excavated contaminated soil,
environmental impacts would be further mitigated with treatment of lead-contaminated soil (as
proposed in Alternatives 5, 6, 7, and 8).  However, treatment alternatives would require the
greatest length of time to achieve the remedial response objectives, and, consequently, the
short-term airborne dust control would continue for the longest period of time under these
treatment alternatives.

Reduction of Toxicity, Mobility, or Volume Through Treatment

       This criterion addresses the statutory preference for selecting remedial actions that
employ treatment technologies that permanently and significantly reduce the toxicity, the
mobility or the volume of the contaminants.  The lead-contaminated residential soil is not
classified as a principal threat; therefore, there is no expectation under 40 CFR °
300.430(a) (1) (iii)  that the soil should be treated.  Alternatives 2, 3, and 4 are not treatment
remedies.  Alternatives 5, 6p 7, and 8 are treatment remedies.  Alternative 5,
stabilization/solidification, would effectively reduce waste material mobility; however, the
original contaminant toxicity would remain a disposal issue requiring long-term monitoring;
moreover, the volume requiring management may actually be increased.  Alternatives 6, soil
washing/leaching, and Alternative 8, electrokinetic remediation, would serve to reduce the waste
material volume; however, the original toxicity and mobility of contaminants would exist in the
remaining treatment residuals, requiring proper management.  Alternative 7, lead reduction
through chemical treatment, should reduce the valence state of lead contaminants and, as such,
would reduce the toxicity and mobility of the contaminated material, with minimal waste volume

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increases requiring management. Alternative 4 would essentially limit direct contact exposure
changing the volume, mobility, or toxicity, and without removing the long-term risk potential of
the contamination. No treatability studies using Site soils have been conducted for any of the
treatment technologies used for the treatment remedies (Alternative 5 through 8). Treatability
studies would be needed for all the treatment technologies utilized by Alternatives 5 through 8
prior to initiation of remedial action in order to access all implementability considerations.

Implementabili ty

This criterion addresses the technical and administrative feasibility of implementing an
alternative, and also addresses the availability of various services and materials required
during the alternative's implementation. The no-action alternative is a non-implementation
option. With regard to technical implementabilty, the non-treatment remedies (Alternatives 2,
3, and 4) are more implementable (i.e., they have higher technical implementability) than the
remedies that treat the soil following excavation from the yards (Alternatives 5, 6, 7, and 8).
The treatment components of these alternatives are not as well developed as the non-treatment
components (e.g., excavation, backfilling, turfing, and other straightforward, well-developed
construction technologies). The treatment components would require bench- and/or pilot-scale
testing to ensure their effectiveness, particularly for innovative technologies. Alternative 4
has high technical implementability, in that the type of construction required is
straightforward. Alternatives 2 and 3 also have high technical implementability in that they
utilize basic construction technologies which are well developed.

With regard to administrative implementability, none of the alternatives pose significant
administrative implementation problems at the Site, except for Alternative 3. The degree to
which Alternative 3 relies on CPMs poses significant administrative problems at the Tar Creek
Superfund Site. Under Alternative 3, contaminated soil with lead concentrations between the
remediation goal (500 ppm) and the action level (800 ppm) would remain in place, posing a
residual risk to children's health. Perpetual CPMs are required under Alternative 3 in order to
address this residual risk. The future cooperation of the public and governmental entities,
upon which a successful CPM program for the Site would rely, is unpredictable. Alternative 3,
by relying on CPMs to address residual risks, also shifts the costs and implementation of
addressing the residences, with surface soil contamination below the 800 ppm level, to the post
construction operation and maintenance (O&M) phase. The responsibility for the O&M phase would
primarily be borne by the State and local governmental entities who in general have expressed
concern about the long-term effectiveness of CPMs and have not expressed a willingness to fund
permanent CPMs on the scale associated with Alternative 3. For these reasons, in the long-term
it is not practicable to implement Alternative 3 at the Site.

Cost Effectiveness

This criterion addresses the cost effectiveness of the alternatives based on direct and
indirect capital costs. Operation and maintenance costs incurred over the life of the project,
as well as present worth costs, are also evaluated. A summary of the costs for the remedial
action alternatives evaluated is presented in Table 2.

The no-action alternative is a no-cost alternative. The no- action alternative does
nothing to actually reduce the risks at the Site, and is therefore not protective of human
health. Comparing present worth costs of the other alternatives, the treatment remedies
(Alternatives 5, 6, 7, and 8), which treat the soil excavated above the 500 ppm soil lead level,
are the most expensive. However, the small increase in effectiveness realized by treating the
excavated soil, rather than just disposing of the excavated soil without treatment, as in
Alternative 2, is not proportional to the significant additional costs required for treatment.
Of the treatment remedies, Alternative 7 has the lowest cost, and Alternative 6 has the highest

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cost. Of the remaining two treatment remedies, Alternative 5 is more expensive than Alternative
8. Overall, the treatment remedies are similar in effectiveness. The overall effectiveness of
each of the treatment remedies is not proportional to the significant increase in cost which
treatment requires. Alternative 4, capping in-place, is the least expensive alternative, but,
because future cap maintenance is uncertain, and because capping creates drainage problems,
Alternative 4 is, relatively, the least effective of all the alternatives, except for the
no-action alternative. Moreover, under Alternative 4, there is a significant potential for
operation and maintenance cost to escalate in the future due to drainage problems. As a result
of such cost escalation, it is likely that Alternative 4 would lose much of its cost advantage
over the other alternatives.

Alternative 2 is cost-effective because its increased cost compared to the lower-cost
alternatives (Alternative 3, Alternative 4, and the no-action alternative) is proportional to
its increased overall effectiveness compared to the overall effectiveness of the lower-cost
alternatives.

The increased cost of Alternative 2 is proportional to the overall increased effectiveness
of Alternative 2 compared to the effectiveness of Alternative 3. The increased cost is
proportional because Alternative 2 addresses about 1,312 residential properties by using a
permanent excavation remedy--a remedy which is effective over the long-term; whereas,
Alternative 3 only addresses about 619 residential properties with a permanent excavation
remedy. In order to address the remaining residences, Alternative 3 uses CPMs which cannot be
relied upon to provide long-term effectiveness and permanence at the Site. Moreover, the annual
operation and maintenance costs for Alternative 3, which includes the maintenance of a permanent
CPM office at the Site, are much higher than the operation and maintenance costs of Alternative
2. As a result, in the long term, Alternative 3 would lose much of its cost advantage over
Alternative 2.

The increased cost of Alternative 2 is proportional to the overall increased effectiveness
of Alternative 2 compared to the effectiveness of Alternative 4. The increased cost is
proportional because Alternative 2 addresses the residences by excavating the contaminated
soil—a permanent remedy; whereas, Alternative 4 utilizes capping which may be breached and
which is likely to cause drainage problems and erosion problems leading to further migration of
contamination. That is, Alternative 2 utilizes a permanent remedy, but Alternative 4 does not.

Cost of Carry-Over Properties: When the remedial action for the residential areas begins,
the removal actions for the residential areas will be phased out. Removal actions at all the
residential properties targeted for removal action at the Site may not be complete at the time
that the remedial action starts. For example, although EPA's March 21, 1996, Action Memorandum
for the Site calls for a removal response action at approximately 300 residential properties
with soil lead concentrations which exceed the removal action level of 1,500 ppm, removal
actions may not be completed at all of those residential properties before the remedial action
begins under this ROD and before the removal action is phased out. Any residential properties
targeted for removal action (including residential yards and HAAs), but unremediated by the
removal program, will be addressed by and included in the remedial action described in this ROD.
Until the remedial action begins and the removal action is phased out, it is unknown how many of
theses properties will be carried over from the removal program to the remedial program
(hereinafter carry-over properties). These carry-over properties will add to the total number
of properties to be addressed by the remedial action. The cost estimates for the remedial
action alternatives (RAAs) evaluated in preparation for this POD, do not include the cost to
remediate these additional carry-over properties. Therefore, the costs for each of the RAAs
would increase by the additional amount required to remediate these carry-over properties.

Modifying Criteria

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State Acceptance

       The State concerns that were assessed included the following:  (1)  The State's position and
key concerns related to the preferred alternative and other alternatives; and (2) State comments
on ARARs.  Comment letters from ODEQ, the Inter-Tribal Environmental Council of Oklahoma(ITEC),
the Quapaw Tribe of Oklahoma, and the Wyandotte Tribe of Oklahoma are included as Appendices B
through E to this ROD, respectively. A complete summary of the comments received from ODEQ,
ITEC, the Quapaw Tribe, and Wyandotte Tribe  (hereinafter collectively referred to as the State
and Tribes)  during the public comment period and EPA's responses to those comments are included
in the Responsiveness Summary which is Appendix A of this ROD.  A summary of the main comments
from the State and the Tribes received before and during the public comment period is as
follows:

       a.   The State and the Tribes prefer Alternative 2.

       b.   The State and the Tribes do not believe that CPMs can effectively address the
            residual risk posed by soil left in place with lead concentrations between 500 ppm
            and 800 ppm as called for under Alternative 3.

       c.   The State and the Tribes have expressed that the treatment alternatives  (Alternatives
            5, 6, 7, and 8) ar( not cost-effective when compared to the non-treatment
            alternatives.  The State and the Tribes have expressed that the small net increases
            in benefits provided by the treatment alternatives compared to the non-treatment
            alternatives do not justify the much higher costs of the treatment alternatives.

       d.   The State and the Tribes have expressed that Alternative 4 (Capping In-Place)  is not
            practical due to the potential for disruption of the caps in a residential setting,
            and due to the potential for the creation of drainage problems.

       e.   The State and the Tribes have expressed that under Alternative 2, health education
            and monitoring may be necessary for those residences where EPA was not granted access
            to remediate the soil.

       f.   The State and the Tribes have expressed concerns about the difficulty EPA is having
            in obtaining access to the Indian lands at the Site in order to conduct response
            actions.  To facilitate obtaining access to the Indian land,  the State and the Tribes
            have suggested that EPA should do more to alleviate the concerns that the owners of
            Indian land have regarding owner liability under CERCLA;  moreover, the State and the
            Tribes believe that EPA should do more to educate the owners of Indian remediation.

       g.   The State and the Tribes have suggested that some remedial response actions should be
            extended to areas that are impacted in the Miami area.

Community Acceptance

       The EPA' s assessment of community acceptance included a determination regarding which
components of the alternatives that interested persons in the community support, have
reservations about, or oppose.  Generally speaking, those individuals living on the Site (i.e.,
those most affected by the remedial action)  support EPA's preferred alternative—Alternative 2.
With the exception of comments from mining companies that formerly operated at the Site and the
Department of the Interior which manages Indian land at the Site, the public expressed support
for EPA's preferred alternative.  A complete summary of the comments on the Proposed Plan
received from the public during the public comment period and EPA' s responses are included in

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the Responsiveness Summary which is Appendix A of this ROD.

IX. SEIiECTED REMEDY

Based upon consideration of the requirements of CERCLA, and based on consideration of the
requirements of the NCP includinq without limitation a detailed analysis of the remedial action
alternatives usinq the nine NCP criteria [40 CFR ° 300.430 (e) (9)] that included, amonq other
thinqs, an analysis of public comments, EPA has determined that Alternative 2 (Soil Excavation
with a 500 ppm Action Level), is the most appropriate remedy for the residential areas in OU2 of
the Tar Creek Superfund Site in Ottawa County, Oklahoma. The selected remedy provides adequate
protection of human health and the environment, complies with ARARS and is cost-effective.

The EPA estimates that surface soil at approximately 1,312 residential yards contains
concentrations of lead which exceed 500 ppm. This estimate does not include the approximately
300 residential yards tarqeted for response action under the onqoinq removal action. Any
contaminated residential properties not addressed by the removal action will be addressed by the
action.

The selected remedy requires the excavation of soil with a lead concentration qreater than
or equal to 500 ppm to a maximum depth of 18 inches in contaminated parts of the residential
areas on the Site. Individual hot spots in the residential areas, for example a part of a
residential property where it is obvious that chat is present (even thouqh random samplinq which
took place at that property found no contamination above the 500 ppm lead level), will also be
addressed on a case-by-case basis. Most soil in lead-contaminated residential yards will be
excavated usinq liqhtweiqht mechanical excavation equipment. Hand excavation methods will be
used to remove soil in areas where mechanical excavation is not suitable. Excavated soil will
be placed into trucks for transportation to the disposal area.

If soil lead concentrations exceed 500 ppm at 18 inches of soil depth, a marker consistinq
of a qeotextile fabric or other suitable material will be placed in the excavated area prior to
backfillinq. The main purpose of the marker is to alert the resident or others of the
contamination remaininq at depth in the event of any future diqqinq or construction.

The type of material used to backfill areas which EPA excavates will depend on the use of
the particular area in question. Yard areas (i.e., the curtilaqe of residential homes) will be
backfilled with clean topsoil and reveqetated. In residential yards, and other open unpaved
areas, qrass will typically be reestablished usinq soddinq, but seedinq will be used when it is
advantaqeous to do so. Lead-contaminated driveways and other traffic areas will be backfilled
with road base material (e.g., qravel or crushed limestone). Some lead-contaminated soil with
lead concentrations above the action level, which is located in driveways and traffic areas, may
be excavated to less than 18 inches if it is clear that the areas will continue to be used
primarily as driveways or traffic areas in the future. These contaminated driveways or traffic
areas may also be paved over, leavinq the lead-contamination in place. Some lead-contaminated
traffic areas (e.g., chat-covered alleyways), may be surfaced with base coarse material and/or
paved without first excavating any contaminated soil.

An x-ray fluorescence (XRF) instrument may be used for post-excavation soil analysis in
order to confirm that remediation qoals are beinq achieved. Utilization of XRF instrumentation,
instead of other more traditional soil analytical methods, minimizes analytical turnaround time
and costs.

All excavated contaminated soil will be disposed of on-Site in dry mininq waste areas
which are already contaminated. The planned on-Site disposal area is the former location of a
milling pond which is now dry. The disposal area is located on private land between Picher and

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Commerce on County Road E40 near the location of the old Eagle-Picher Central Mill. Public
access to the disposal area is restricted. The planned disposal area is already contaminated
with lead above the 500 ppm level. The disposal area is presently being utilized for the
removal actions currently in progress. The soil excavated from the residential areas will be
spread over the disposal area to blend into the contours of the surrounding land. Once EPA has
finished using the disposal area, the disposal area will he vegetated with grass. The grass
will help control erosion by wind or water. The disposal area will also be capped with clean
soil prior to vegetating, unless the surface of the disposal area already has soil lead
concentrations less than 500 ppm. Contaminated soil excavated from the residential properties
will generally be removed in 6-inch layers, and, conseguently, this excavated soil usually
contains some soil with lead concentrations less than 500 ppm. As the excavated soil is
handled, incidental mixing will generally occur, and generally soil lead concentrations greater
that 500 ppm will be reduced due to dilution from this mixing. As a result of mixing during
normal handling of excavated soil, soil contamination in many parts of the disposal area may be
lower than the remediation goal; conseguently, no clean soil cap will be needed in these parts.
Since the residential soil at the Site is classified as a low level threat and not a principal
threat, containment without treatment is consistent with CERCLA and the NCP.

In situations where it is more feasible for governmental entities other than EPA to
perform remediation activities, for example using city maintenance crews to repair streets
damaged by remediation activities or to surface alleyways in residential neighborhoods,
agreements with other government entities to perform the work at EPA expense will be considered.

Water spraying will be used for dust suppression during excavation of contaminated soil.
Dump trucks used to transport contaminated soil will be eguipped with covers to prevent dust
from blowing. To assure that the dust suppression activities are adeguate to protect residents
and workers, an air monitoring program will be implemented. The program will consist of
real-time dust monitoring as well as air sampling.

The engineering remedial response actions for the residential yard and HAA area portions
of the selected remedy will be consistent with the removal action for the residential yards and
HAAs.

The selected remedy also contains the elements described in the Section of this ROD
entitled "Common Elements in All Alternatives" and the seven enumerated paragraphs in the
Section of this ROD entitled "Documentation of Significant Changes."

Cost

The construction cost of the selected remedy is estimated at $26,764,400, as shown on
Table 1. This is based on an estimate of the overall cost of $20,000 per residential property.
The overall cost includes all construction and associated activities reguired to address the
lead contamination in the residential areas at the Site, except for the contracting agency
administration cost. The contracting agency administration cost is estimated to be $2,676,440
which is 10 percent of the construction cost of $26,764,400. The total estimated remedial
action cost is $29,440,840 which consists of the construction cost ($26,764,400) plus the
contacting agency administration cost ($2,676,440). Annual O&M after construction is completed,
including without limitation the maintenance of the disposal area and supplemental institutional
controls, is estimated to cost $60,000.

X. STATUTORY AUTHORITY FINDINGS AND CONCLUSIONS OF LAW

The EPA's primary responsibility at Superfund sites is to select remedial actions that are
protective of human health and the environment. Section 121 of CERCLA, 42 U.S.C. ° 9621, also

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requires that the selected remedial action for a site comply with applicable or relevant and
appropriate environmental standards established under Federal and State environmental laws,
unless a waiver is granted. The selected remedy must be cost-effective and utilize treatment or
resource recovery technologies to the maximum extent practicable. The statute also contains a
preference for remedies that include treatment as a principal element. The following sections
discuss how the selected remedy for residential soil at the Tar Creek Superfund site meets the
statutory requirements.

A. Protection of Human Health and the Environment

The selected remedy provides protection by excavation of lead-contaminated soil at or
above the health-risk-derived level of 500 ppm to a maximum depth of 18 inches with complete
removal of the excavated soil from the residential areas, followed by backfilling with clean
soil. The selected remedy supplementally provides protection by other engineering elements and
institutional controls detailed in the Section of this ROD entitled "Common Elements in All
Alternatives," and the seven enumerated paragraphs in the Section of this ROD entitled
"Documentation of Significant Changes."

The selected remedy provides protection primarily by reducing concentrations of
contaminants through excavation and removal of contaminated soil from residential areas. The
protection provided by the selected remedial alternative is equivalent to or better than the
protection offered by any of the other alternatives evaluated for the remediation of lead-
contaminated soil in the residential areas. As explained above in the Section of this ROD
entitled "Short-term Effectiveness," no unacceptable short-term risks will be caused by
implementing this selected remedy. ROD Section IX, "Summary of Comparative Analysis of
Alternatives," and ROD Section X, "The Selected Remedy," provide an analysis of the ways in
which the selected remedy provides the best overall protection of human health and the
environment, and explains that the selected remedy causes no unacceptable short-term risk.

B. Compliance With ARARs

The selected remedy which consists primarily of the excavation and disposal of the
residential soil will attain all applicable or relevant and appropriate requirements (ARARs).
Tables 3 through 5 of this ROD list ARARs developed for the remedial action of the residential
areas for the Tar Creek Superfund Site. A summary of the evaluation of the ARARs is provided
below:

b. Location-specific ARARS - All proposed activities at the Site are compliant with
location-specific ARARs.

c. Action-specific ARARs - The lead contamination in the soil is primarily from mining
waste (overall the evidence leads to this conclusion) which is a solid waste, but not
a hazardous waste under the Resource Conservation and Recovery Act (RCRA) because it
is solid waste from the extraction, beneficiation, and processing of ores and
minerals, according to 40 CFR ° 261.4(b)(7). Disposal of excavated lead-contaminated
soil will be on-Site within the area of contamination, but away from residential
areas. Dust generation will be controlled during construction to meet relevant and
appropriate Federal and State air quality laws and regulations.

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d. To-be-considered (TBCs) - In addition to ARARs, other advisories, criteria, or
guidance that may be useful in developing the remedy were, as appropriate, identified
and considered.

C. Cost-Effectiveness

The EPA believes that the selected remedy is cost-effective in mitigating the threat of
direct contact with contaminated residential soil because its costs are proportional to its
overall effectiveness. The NCP at 40 CFR °300.430(f)(ii)(D) reguires EPA to determine
cost-effectiveness by evaluating the following three of the five balancing criteria to determine
overall effectiveness: long-term effectiveness and permanence, reduction of toxicity, mobility
or volume through treatment, and short-term effectiveness. Overall effectiveness is then
compared to cost to ensure that the selected remedy is cost-effective. The EPA believes the
selected remedy meets these criteria.

The estimated cost of the selected remedy (Alternative 2) for the residential soil is
$26,764,400 (capital cost). The no-action alternative is a no-cost alternative. The no-action
alternative is ineffective. It does nothing to actually reduce the risks at the Site, is not
protective of human health, and, therefore, cannot be selected under the NCP criteria.
Comparing present worth costs of the other alternatives, the treatment remedies (Alternatives 5,
6, 7, and 8), which treat the soil excavated above the 500 ppm soil lead level, are the most
expensive. However, the small increase in effectiveness realized by treating the excavated
soil, rather than just disposing of the excavated soil without treatment, as in Alternative 2,
is not proportional to the significant additional costs reguired for treatment. Of the
treatment remedies, Alternative 7 has the lowest cost, and Alternative 6 has the highest cost.
Of the remaining two treatment remedies, Alternative 5 is more expensive than Alternative 8.
Overall, the treatment remedies are similar in effectiveness. The overall effectiveness of each
of the treatment remedies is not proportional to the significant increase in cost which
treatment reguires. Alternative 4, capping in-place, is the least expensive alternative, but,
because future cap maintenance is uncertain, and because capping creates drainage problems,
Alternative 4 is, relatively, the least effective of all the alternatives, except for the
no-action alternative. Moreover, under Alternative 4, there is a significant potential for
operation and maintenance cost to escalate in the future due to drainage problems. As a result
of such cost escalation, it is likely that Alternative 4 would lose much of its cost advantage
over the other alternatives.

The increased cost of Alternative 2 is proportional to the overall increased effectiveness
of Alternative 2 compared to the effectiveness of Alternative 3. The increased cost is
proportional because Alternative 2 addresses about 1,312 residential properties by using a
permanent excavation remedy--a remedy which is effective over the long-term; whereas,
Alternative 3 only addresses about 619 residential properties with a permanent excavation
remedy. In order to address the remaining residences, Alternative 3 uses CPMs which cannot be
relied upon to provide long-term effectiveness and permanence at the Site. Moreover, the annual
operation and maintenance costs for Alternative 3, which includes the maintenance of a permanent
CPM office at the Site, are much higher than the operation and maintenance costs of Alternative
2. As a result, in the long-term, Alternative 3 would lose much of its cost advantage over
Alternative 2.
The increased cost of Alternative 2 is proportional to the overall increased effectiveness
of Alternative 2 compared to the effectiveness of Alternative 4. The increased cost is

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proportional because Alternative 2 addresses the residences by excavating the contaminated
soil—a permanent remedy; whereas, Alternative 4 utilizes capping which may be breached and
which is likely to cause drainage problems and erosion problems leading to further migration of
contamination. That is, Alternative 2 utilizes a permanent remedy, but Alternative 4 does not.

All of the alternatives have controllable short-term impacts and none have unacceptable
short-term risks. Therefore, short-term effectiveness was not a major factor in the
consideration of overall effectiveness as used in the cost-effectiveness evaluation.

D. Utilization of Permanent Solutions and Treatment or Resource Recovery Technologies to the
Maximum Extent Practicable

The EPA believes that the selected remedy represents the maximum extent to which permanent
solutions can be utilized in a cost-effective manner for the Tar Creek Superfund Site.
Treatment/resource recovery technologies cannot be utilized in a cost-effective manner for the
Tar Creek Superfund Site. All of the treatment alternatives (Alternatives 5, 6, 7, 8) were
significantly more expensive than the selected remedy. However, small increase in effectiveness
by treating the excavated soil, rather than just disposing of the excavated soil without
treatment, as in the selected remedy, is not proportional to the significant additional cost for
treatment. Alternative 8 is the only alternative that allows possible resource recovery because
it permanently separates metals from the soil so that it may be sold and beneficially reused.
High concentrations of soil lead are addressed under the remedy selected in this ROD; however,
the mobility of the soil lead is low, and the concentrations of lead are not so high as to be
several orders of magnitude above levels that allow for unrestricted use and unlimited exposure.
Therefore, the soil lead is not considered a principal threat under the NCP; conseguently, there
is no expectation under the NCP that the soil lead be treated. Remedies which involve resource
recovery are preferred under CERCLA Section 121(b), 42 U.S.C. ° 9621 (c) . However, the
difference in cost of Alternative 8 over the selected remedy is greater than the potential value
of metals that could be recovered. Therefore, resource recovery technologies were not deemed
appropriate for this Site.

E. Preference for Treatment as a Principal Element

This criterion addresses the statutory preference for selecting remedial actions that
treat principal threats in order to permanently and significantly reduce the toxicity, the
mobility or the volume of the contaminants. High concentrations of soil lead are addressed
under the remedy selected in this ROD; however, the mobility of the soil lead is low, and the
concentrations of lead are not so high as to be several orders of magnitude above levels that
allow for unrestricted use and unlimited exposure. Therefore, the soil lead is not considered a
principal threat under the NCP; conseguently, there is no expectation under the NCP that the
soil lead be treated. The lead-contaminated residential soil is not classified as a principal
threat; therefore, there is no expectation under 40 CFR ° 300-430(a) (1) (iii) that the soil
should be treated. Alternatives 2, 3, and 4 are not treatment remedies. Also, the treatment
remedies (Alternatives 5, 6, 7, and 8) were not cost-effectiveness compared to the selected
remedy.

XI. DOCUMENTATION OF SIGNIFICANT CHANGES

The Proposed Plan for the Tar Creek Superfund Site was released for public comment on
March 17, 1997. The Proposed Plan identified Alternative 2, (Soil Excavation with a 500 ppm
Action Level), as the preferred alternative to address the contamination from mining waste in
the residential areas of the Site. The EPA reviewed all written and verbal comments submitted
during the public comment period. Upon review of these comments, it was determined that
significant changes to the remedy, as originally identified in the Proposed Plan, were

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necessary.  The significant changes are a logical outgrowth of the information available in the
Administrative Record and comments received from the public.  The response actions reguired by
these changes are the same types of actions originally planned; however, the scope of the
response action has been extended to other areas and communities in Ottawa County which are
outside of the boundaries of the mining area, but which have been impacted by mining waste.

       Comments submitted during the public comment period have led EPA to reexamine the
remediation approach which it will take under this remedial action regarding certain other areas
on the Site which are contaminated by lead-contaminated mining waste.  These other
lead-contaminated areas are not in residential yards, but may affect children living in
residential areas due to the proximity of these other areas to the residences,  or due to the
fact that lead contamination may be migrating from these other areas into the residential areas.

       On or near the residential areas of the Site,  lead- contaminated mining waste is found in
many chat piles and in many locations where milling discharge ponds were once located  (these
pond areas are now generally dry).  Moreover, on or near the residential areas of the Site,
lead-contaminated chat has been used in alleyways, parking lots, roads, driveways, and other
areas.  Natural armoring, crusting and vegetation helps to reduce the amount of lead released
from these various places which contain lead-contaminated material on or near the residential
areas of the Site.  However, any of these places which hold lead-contaminated mining waste on or
near the Site, when disturbed by vehicle traffic, foot traffic, or other physical disruption,
become sources for further spread of contamination to residential areas, and they also become
sources of potential recontamination of the residential areas where lead contamination has been
cleaned up or will be cleaned up under this ROD.  In addition, children who live on the Site,
may wander into these uncontrolled areas, and come into direct contact with this
lead-contaminated mining waste on the surface of the ground.  These children may ingest
dangerous levels of lead via normal hand-to-mouth contact during play in these areas.

       During the public comment period,  EPA also received comments which pointed out that
certain residential communities in Ottawa County, which were not within the scope of EPA's
Proposed Plan, have had lead-contaminated mining waste placed in these communities. These
communities were not within the scope of EPA's Proposed Plan because they are outside the
historic mining and milling area (hereinafter the mining area) which EPA had generally defined
as the "Site"  However, as the comments explained, and as EPA investigations have determined,
lead-contaminated mining waste has been transported to nearly all of the communities in Ottawa
County which are located outside of the mining area  (as well as to those communities within the
mining area).  In these communities located outside the mining area, the lead-contaminated
mining waste has been used for driveway material, playground material, and for other uses for
which loose gravel is typically used.  Accordingly, since children in these other communities,
which were not within the scope of the Proposed Plan, may come into contact with this
lead-contaminated waste, and since the children may ingest dangerous levels of lead via normal
hand-to-mouth contact during play in these areas, EPA has decided to expand the Site to include
these other communities under the scope of this ROD.   Generally the contamination in these other
communities is such that it will not reguire the extensive yard-soil excavation and soil
disposal  (with the exception of the HAAs which may reguire extensive excavation) which is
planned for the residential areas located within the mining area.  Instead, as described below,
this ROD generally calls for institutional controls,  coverage or replacement of chat in traffic
areas, and establishment or improvement of ground cover (e.g., grass) for the communities
located within Ottawa County, but outside the mining area; however, if EPA should come across
residential areas (including without limitation HAAs) with soil lead concentrations over 500
ppm, this ROD gives EPA the authority to undertake the selected soil removal actions (i.e.,
Alternative 2) in these residential areas outside of the mining area.

       Finally, Tar Creek,  which flows near residential areas of the Site is contaminated with

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lead. In addition to lead contamination from acid mine discharges from the underground mine
workings, leachate and surface water runoff from the mining waste on the surface of the ground
also contain lead which contributes significantly to the contamination of the waters of Tar
Creek. From time to time, Tar Creek overflows its banks, and flood waters contaminated with
lead flow into the residential areas located downstream on the Site, depositing a sediment
containing lead. These lead-contaminated sediments in some instances may hold dangerous
concentrations of lead (levels in excess of 500 ppm), and children who live in flooded
residential areas may come into contact with the sediment once the flood waters recede. These
children may ingest dangerous amounts of lead from this sediment via normal hand-to-mouth
contact during play.

In light of the comments described above and EPA's investigations, and based on documents
in the administrative record for this ROD, EPA has made significant changes between the ROD and
the Proposed Plan as follows:

1. The Site is expanded to include all portions of Ottawa County impacted by mining
waste.

2. Response actions prescribed in Alternative 2 for the residential areas within the
mining area will also apply to the floodplain of Tar Creek, including the portion of
the floodplain in Miami, and to the HAAs outside the mining area in Ottawa County.

3. Institutional controls, including without limitation health education,
lead-contaminated dust reduction activities, and blood lead monitoring are extended
to include more residential communities than just the residential areas in the mining
area. Institutional controls under the ROD will be extended to community-wide
application in all residential communities, including Miami, within Ottawa County.

4. Road base material (e.g., gravel or crushed limestone) will be used to cover or
replace chat material in alleyways, parking lots, roads, driveways, and other such
areas near mining area residences, and near residences in communities, including
Miami, within Ottawa County. Decisions to replace or cover chat material and
decisions on which areas reguire such remediation will be made on a case-by-case
basis during the remedial design and remedial action.

5. Physical barriers (e.g., fences and warning signs) will be used, as appropriate, to
restrict access to mining waste which is located near residences. Physical barriers
were included in the Proposed Plan in order to restrict access to contaminated
property, but the change described in this paragraph extends the use of physical
barriers to broader application in the mining area and throughout Ottawa County.

6. For certain residential properties generally outside the mining area, but within
Ottawa County, establishment or improvement of ground cover (e.g., grass) will be
used to address bare contaminated soil areas. Decisions to provide or improve ground
cover and decisions on which areas reguire such remediation will be made on a
case-by-case basis during the remedial design and remedial action.

7. For certain residential properties generally outside tho mining area, but within
Ottawa County, where medical monitoring has found that a resident has elevated blood
lead levels close to or greater than 10 ug/dL, and where the residential yard is
contaminated with lead-contaminated soil with concentrations at or above 500 ppm, the
soil will be excavated and replaced as called for under the selected remedy.

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       The costs for these significant changes to the Proposed Plan would not significantly
affect the comparative analysis of the RAAs, since the cost of each of the RAAs would increase
by about the same amount with the addition of these changes.  The costs of the selected remedy
as set forth in this ROD are within +50% to -30% of the costs estimated for the preferred
alternative in the Proposed Plan.  Any differences in cost estimates between the Proposed Plan
and the remedial action did not affect selection of the final alternative.

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                                                    TABLES
                                                    TABIiE 1
                                    SUMMARY OF ANALYTICAL RESULTS FOR LEAD
                                               Residential Areas
                                           Tar Creek Superfund Site

[The following chart is a summary of the lead-contamination levels in three media that were
sampled from the Study Group residences in Picher, Oklahoma and from the reference  area
residences in Afton, Oklahoma.]

                   Study Group  (PPM 1)             Reference Area  (PPM)

Media         Range of    Mean    Median         Range     Mean    Median
              Values

Yard          156-2218     852      756          40-348     109      70
Soil

Garden         30-1230     339      253          13-76       31      22
Soil

Garden       .033-.137     .05      .03         037-.09    .044     .03
Produce

(1) Parts Per Million

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                                                    Table 2

                                REMEDIAL ACTION ALTERNATIVES, COST SUMMARY  (1)
                               TAR CREEK SUPERFUND  SITE,  OTTAWA COUNTY,  OKLAHOMA

[The following chart is a summary of the costs of each of the eight remedial  action alternatives
(RAAs).   The costs of each alternative are broken down into capital  (construction) cost, annual
operation and maintenance (O&M) cost, and present worth.  The present worth represents the
amount of money, if invested at the start of the remediation, that would cover all costs
associated with the remedial action over its planned life.]
 RAA
 No.
              RAA
1   No Action

2   Soil excavation  (2),
    500 ppm action level

3   Soil excavation,
    CPMs (3),  800 ppm
    action level
apital Costs


$0
$26,764,400
Annual
O&M
Costs
$0
$60,000
Present
Worth

$0
$24,478,219
$12,764,800
$360,000
$17,194,533
4   Capping in place,
    500 ppm action level

5   Excavate soils,
    stabilize/solidify,
    500 ppm action level

6   Excavate soils,
    wash/leach,  500 ppm
    action level
$14,360,800
$55,694,400
$74,663,600
 $50,000
 $60,000
 $60,000
$14,156,949
$50,136,522
$67,004,294
    Excavate soils, lead
    reduction treatment,
    500 ppm action level
$36,413,600
 $60,000
$33,059,038
    Excavate soils,
    electrokinetic
    treatment,  500 ppm
    action level
$48,265,000
   (4)
$42,763,795
Notes:
       (1)   Capital and operation and maintenance  (O&M) costs are estimated within +50 percent to
            -30 percent.
       (2)   Disposal of all excavated soils would be in dry tailings ponds.
       (3)   Community Protective Measures  (CPMs) would consist of monitoring of affected persons
            and media, health education, and lead exposure reduction measures
       (4)   Alternative 8 permanently detoxifies the lead and no long-term O&M is required.

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                                                    Table 3

                                       POTENTIAL CHEMICAL/SPECIFIC ARARS
                               TAR CREEK SUPERFUND SITE, OTTAWA COUNTY, OKLAHOMA

                                       Citations                  Prerequisite
Requirement

A.  Applicable Requirements                     None

B.  Relevant and Appropriate                    None

C.  To Be Considered                            None

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                                                                                        Table  4

                                                                       POTENTIAL LOCATION-SPECIFIC ARARS
                                                            TAR CREEK  SUPERFUND SITE,  OTTAWA  COUNTY, OKLAHOMA
                                      Citation
                                        Prerequisite
Requirement
                                                                                                                                       The  remedial alternative  will  be designed to
                                                                                                                                       minimize effects on historic landmarks.
                                                                                                                                       Coordinate with State Historic Preservation
                                                                                                                                       Officer  (SHPO).
                                                                                                                                       The  remedial alternative  will  be designed to
                                                                                                                                       minimize effects on historical and
                                                                                                                                       archeological data.  Coordinate with State
                                                                                                                                       Historic Preservation Officer  (SHPO).
    Historic Sites, Buildings,  and
    Antiguities Act
                                           Property within or  near landmarks on the
                                           National Registry of  Natural Landmarks.
            The remedial alternative will be  designed to
            avoid undesirable impacts on such
            landmarks.  Coordinate with State Historic
            Preservation Officer  (SHPO).
    Federal Migratory Bird Act.
    Oklahoma Wildlife Statutes
50 CFR Parts  17, 402
40 CFR 6.302(h)
16 USC 703-712
Title 29,  Section 5-412
            The remedial alternative will be  designed to
            conserve  endangered or threatened species
            and their habitat, including consultation with
            the Department of Interior and the
            Oklahoma  State Department of Wildlife  if
            such areas  are affected.
6.   Nationwide Permit (NWP)
                                                                                                                                       The  remedial alternative  will  ensure that all
                                                                                                                                       activities in affected areas meet regulatory
                                                                                                                                       permit reguirements.

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                                                Table 5

                                  POTENTIAL ACTION-SPECIFIC ARARS
                       TAR CREEK SUPERFUND  SITE,  OTTAWA COUNTY, OKLAHOMA

Citation            Prerequisite                            Requirement
                                                                       Best management practices must be
                                                                       maintained by the operator of the discharge
                                                                       system and discharges must be monitored to
                                                                       assure compliance with effluent discharge
                                                                       limits.

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                                                    FIGURES






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                                                  APPENDIX A

                                          THE RESPONSIVENESS SUMMARY

                                           Tar Creek Superfund Site
                                           Ottawa County, Oklahoma
                                              Residential Areas

This Responsiveness Summary has been prepared by the U.S. Environmental Protection Agency (EPA)
to provide written responses to comments submitted regarding the Proposed Plan of Action for the
residential areas of the Tar Creek Superfund Site (the "Site").   The summary is divided into two
sections as follows:

       Section I:  Background  of Community Involvement and Concerns.   This section provides a
       brief history of community interest and concerns raised during the remedial planning
       activities at the Site.

       Section II:   Summary of Major Comments Received.  The comments,  both oral and written,  are
       summarized and the U.S.  Environmental  Protection Agency's (EPA)  responses provided.
       Section II is divided into Part A and  Part B.   Part B consists of responses to major
       written comments from mining companies that formerly operated at the Site (or their
       successors)  and the U. S.  Department of the Interior (DOI).   Part A consists of responses
       to all the other major comments both oral and written.
I.      Background of Community Involvement and Concerns

       Interest in the residential response actions at the Tar Creek Superfund Site on the part
of the residents, local communities, and local government officials has been moderate compared
to other Superfund sites.  Community relations activities at the Site have a long history.  The
Site was proposed for the National Priorities List (NPL)  in July 1981.  The Site was included on
the NPL in September 1983.  Community relations activities supporting the Operable Unit 1 Record
of Decision,  were scaled back after completion of construction related to Operable Unit 1 in
December 1986.  Community relations activities were increased again in 1994 because EPA began
new response actions at a new operable unit at the Site.   The new response actions were based on
investigations which were recommended in the Five-Year Review which was issued by EPA in April
1994.  A Community Relations Plan  (CRP)  was published and released to the public in June 1995.
The CRP was prepared in order to identify and address community concerns.  Copies of the CRP are
located in the information repositories at the Miami Public Library in Miami, Oklahoma, and in
the EPA Region 6 Office in Dallas, Texas.  The public may review the CRP at those locations
during normal business hours.  The CRP identified found that the primary interest in the Tar
Creek Superfund Site lies mostly with the residents and local community leaders who live on or
near the Site.

II.    Summary of Major Comments Received, Part A

       The EPA conducted an open house public meeting on  February 27,  1997,  to inform the public
of the findings of the Residential Remedial Investigation and Feasibility Study (RI/FS) reports
including the results of the Baseline Risk Assessment. A public notice announcing the public
comment period regarding EPA's Proposed Plan for the remedial action at the residential areas of
the Site, and announcing an opportunity for a public meeting was published in the Miami
News-Record,  on March 14, 1997, through March 16, 1997, and was also published in the Tri-State
Tribune on March 13, 1997, through March 20, 1997.  The Proposed Plan Fact Sheet was distributed
to all the parties listed on the Site mailing list on March 13, 1997.   The EPA conducted a
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public meeting on March 27, 1997, to inform the public about the Proposed Plan of Action.  Also,
at this meeting, representatives from EPA solicited comments and answered guestions about the
Site, the remedial alternatives under consideration, and the Proposed Plan.  The EPA held a
30-day public comment period regarding the Proposed Plan for the residential areas, the Remedial
Investigation (RI) Report, the Feasibility Study (FS)  Report, and the Administrative Record.  A
public comment period was held from March 17, 1997 to April 16, 1997.  The public comment period
was extended to May 16, 1997, due to a reguest for an extension.  The public comment period was
subseguently extended again to May 23, 1997, due to an additional reguest for an extension.  A
notice announcing the extension of the public comment period was published in the Miami
News-Record, on April 16, 1997 and April 17, 1997.

       Approximately fifty people were in attendance at the March 27, 1997, public meeting.  The
public was given the opportunity to make comments or ask guestions at the meeting.  Twenty-three
people made comments or asked guestions.  A full account of the public meeting can be found in
the public meeting transcript, which is contained in the Tar Creek Superfund Site Administrative
Record.  Written comments were received from three citizens groups, two Indian Tribes (Quapaw
and Wyandotte),  the Inter-Tribal Council of Oklahoma and the Oklahoma State Department of
Environmental Quality  (ODEQ), six companies that formerly mined at the Site (or their
successors), and the U.S. Department of the Interior.

a.     Verbal Comments

       The verbal comments/guestions received during the public meeting on March 27,  1997,  are as
follows:

1.     Comment:   For farm homes how will the size of the yard to be remediated be determined?

Response:  The areas, adjacent to or near a residence, that are actually being used for
residential yard purposes  (e.g., lawn areas, children's play areas, garden areas), will be
considered the yard for remediation purposes.  Sizes of areas remediated will vary based on
property-specific considerations.  Adjacent pasture land or agricultural field areas will not be
considered residential yard areas and will not be addressed during this remedial action unless
they are a potential source of recontamination of the remediated residential areas.

2.     Comment:   Is EPA satisfied that the air guality is pretty good in the immediate mining
       area?

Response:  Yes.   Air guality, based on air monitoring of metals in recent years, is generally
good.

3.     Comment:   If air guality is pretty good,  then how did the residential areas become
       contaminated?

Response:  While air deposition of mining waste may have been a more significant contributor
during the active mining years, air monitoring in recent years indicates that air deposition now
is a much less significant source of ongoing contamination to residential properties.  The main
source of contamination of properties, other than residences built on mining waste areas and
other than fugitive dust and spillage during transport during the active mining years, was by
human transport, for example the use of chat for driveways and other purposes.

4.     Comment:   Are the chat piles remaining in the area any danger to the public?

Response:  The potential for contamination of residential properties via the air deposition
route is small for most of the properties.  For some properties, the potential for
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recontamination from nearby chat piles may need to be controlled by appropriate dust and erosion
control measures.  However, we have found that even areas with nearby chat piles generally have
good air guality.  Additional evaluations will be needed to determine if there are other
potential risks to the area's population related to chat piles at the Site.

5.     Comment:  Is water runoff from chat piles a source of contamination to people's yards?

Response:  In general it is not a significant problem.  However, for individual properties it
may be a significant contributor to contamination.  Each property will be evaluated during
remediation.  If water deposition is a problem, then measures such as rerouting drainage will be
conducted to address the recontamination potential.

6.     Comment:  What will the long-term remedial action consist of?

Response:  Basically, the proposed remedial action will consist of the same kind of work (e.g.,
excavation and replacement of lead-contaminated soil) that is being performed by the removal
action that is currently underway at the Site.  The removal action is addressing approximately
300 homes on the Site by excavating lead-contaminated soil wherever lead is found in
concentrations of 1,500 parts lead per million parts soil  (ppm)  or greater.  Wherever those lead
concentrations are found, the soil is excavated until no soil lead concentrations exceed 500
ppm.  Excavated areas are backfilled with clean soil.  The follow-up remedial action will
address all residential areas where soil lead is found at concentrations which exceed 500 ppm.

7.     Comment:  Are there any plans to try to eliminate the contaminated water from Tar Creek
       flowing into the Neosho and eventually into Grand Lake? What impact is metal loading from
       Tar Creek having on Grand Lake?

Response:  Previous investigations by the Governor of Oklahoma's Tar Creek Task Force (Tar Creek
Task Force, Health Effects Sub-Committee, March 1983, Environmental Health Evaluation of the Tar
Creek Area) concluded that the Neosho River and Grand Lake can safely be used as a raw water
source for public water supplies and that fish from the Neosho and Grand Lake are safe for human
consumption.  Most of the metals present in the acid mine water are precipitated out of the
water, and deposited in the Tar Creek stream sediments before the confluence of Tar Creek and
the Neosho River.  The Tar Creek Task Force concluded that the Neosho has received little impact
from Tar Creek other than aesthetic alteration at the confluence.  Additional investigations of
the water guality and fish in the Neosho River and Grand Lake, related to impacts from Tar
Creek, are not considered necessary.

8.     Comment:  Are there any plans for additional remediation to try to eliminate the
       discharges of acid mine water to the surface?

Response:  Approximately 25 billion gallons of water are contained within the old subterranean
mine workings.  There are technologies that might work on a small scale, but an application that
would be economically feasible on the scale  necessary to address the Tar Creek problems has not
been identified.

9.     Comment:  Are there any plans to test sediment in the bottom of Grand Lake?

Response:  Studies by the U.S. Fish and Wildlife Service (U.S. Fish and Wildlife Service,
National Reservoir Research Program, 1983, "Effects of Acid Mine Drainage from Tar Creek on
Fishes and Benthic Macroinvertebrates in Grand Lake, Oklahoma")  and more recent studies by the
Oklahoma Water Resource Board and Oklahoma State University as part of the Clean Lakes Project
(Oklahoma Water Resources Board, Water Quality Programs Division and Oklahoma State University,
Water Quality Research Lab, March 10, 1995, Phase I of Clean Lakes Project, Final Report,
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"Diagnostic and Feasibility Study of Grand Lake 0' the Cherokees") indicate that the metals at
the upper reaches of Grand Lake, where possible impacts of mining would be expected to be the
greatest, are bound in the sediments and do not significantly impact fish or water quality.
Also, the concentration levels of hazardous metals in the sediments are below levels which are a
risk to humans.  No further studies of Grand Lake, related to the impacts of Tar Creek, are
recommended by EPA.

10.    Comment:  How does the Neosho River as influenced by Tar Creek and Spring River compare as
       sources of metal loading to Grand Lake?

Response:  Samples of sediment indicate that Spring River is a much greater source of metal
loading than the Neosho River.

11.    Comment:  If the chat piles are so full of heavy metals,  why are they still being allowed
       to be sold and transported out of the area?

Response:  CERCLA generally addresses uncontrolled releases of hazardous substances that pose a
threat to human health or the environment.  The Resource Conservation and Recovery Act  (RCRA)
generally provides a "cradle to grave" control of hazardous wastes ensuring that such wastes are
properly stored, transported, treated and ultimately disposed.  The EPA has not identified an
uncontrolled release that poses a threat to human health or the environment at the loading
facilities where chat is shoveled into trucks for commercial use; consequently, EPA has not
identified a situation in which CERCLA authority applies at the loading facilities (further
investigations may identify such a threat).  Moreover, since the chat is a solid waste from the
extraction, beneficiation, and processing of ores and minerals,  it is not classified as a
hazardous waste under RCRA; therefore, RCRA's hazardous waste regulations do not apply.  If the
chat is washed to eliminate fine material, and then used in an application in which it is fixed
within another material  (e.g., where it is used as an ingredient in asphalt or concrete) it
should not pose a threat; consequently, it can be sold for industrial use.  Other Federal
environmental laws do not generally apply to the chat.  The EPA does caution the public about
potential liabilities with regard to improper uses of the chat or other mining waste material.
The EPA has provided, and will continue to provide information regarding the types of uses that
can have safe applications and which types of uses are considered unsafe.

12.    Comment:  Have the alleyways,  streets,  and driveways been tested?

Response:  As part of the residential response action within the mining area, the driveways are
tested.  If they are contaminated, the driveways are remediated.  The alleyways, streets, and
other traffic areas are not generally being tested.  For these areas, if they are surfaced with
chat, the plan is to replace or surface the chat with road base material, typically crushed
limestone.

13.    Comment:  When will the remediation of the traffic areas  other than driveways begin?

Response:  The EPA is planning to begin providing crushed limestone to the local cities within
the mining area starting in the Fall 1997.

14.    Comment:  What is the average yard remediation costing under the removal actions?

Response:  Approximately $15,000 to date.  As remediation continues into areas such as the City
of Picher, with some larger yards, this average figure could go up.  An average remediation cost
per yard of $20,000 has been estimated for the long-term remedial action.

15.    Comment:  What is the volume of soil material that will be excavated during the remedial
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       action?

Response:  The volume to be excavated during the remedial action is estimated at approximately
364,000 cubic yards.

16.    Comment:   What will the long-term remediation cost for the residential areas?

Response:  The cost of the remedial action for the residential areas is estimated at
$29,440,840.

17.    Comment:   How will the remediation be funded?

Response:  The cost of the remedial action will be funded by EPA's Superfund unless potentially
responsible parties agree to fund or conduct the work.  Also, for Superfund financed projects
the State is reguired to pay a 10% cost match.  For the Tar Creek Superfund Site the State would
not cost match on the Indian-owned properties.  For the Indian-owned properties, the 10% cost
match for Superfund-financed remediation is not applicable.

18.    Comment:   Which properties will be remediated?

Response:  All residential properties are proposed for remediation, Indian and non-Indian.

19.    Comment:   Would it not be cheaper to relocate the residents rather than clean up the
       residences?

Response: No.  Relocation is estimated to be approximately ten times more expensive.  Also, even
if the residents were relocated, EPA would have to address the contamination so that the area
could be used in the future.

20.    Comment:   Has not the Federal government relocated towns before?

Response:  Yes.   A remedial action may include the costs of permanent relocation of residents
and businesses and community facilities where EPA determines that alone or in combination with
other measures such relocation is more cost-effective than, and environmentally preferable to,
the transportation, storage, treatment, destruction or secure off-site disposition of the
hazardous substances in guestion, or if relocation is otherwise necessary to protect the public
health or welfare.  Since relocation would be ten times more costly than the remedial action
selected in the ROD, and since EPA has successfully performed soil lead cleanups in other
residential areas, EPA has decided that relocation is not an appropriate response action for the
Site.

21.    Comment:   What percent of the residential area is Indian?

Response:  Approximately 20% of the residential properties are Indian-owned.

22.    Comment:   Has funding been provided by the State for the 10% State match for the
       non-Indian properties? Has the State agreed to pay the operation and maintenance (O&M)
       costs?

Response:  The State has expressed its intention to provide the reguired cost match.  The State
does not have to provide the money prior to the start of the remedial action.  The State will
provide the reguired assurances through a Superfund State Contract to cost match, and to assume
the responsibilities for Operation and Maintenance  (O&M) of the remedy.
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23.    Comment:   Have the EPA attorneys looked into the Indian land liability issue at the Site
       and will  EPA be placing its policy in writing with regard to the liability issues at the
       Site?

Response: The EPA has absolutely no plans to pursue private Indian landowners or private
non-Indian landowners for reimbursement of EPA's costs at the Site.  Moreover, EPA does not
anticipate that it will ever have such plans in the future.  Although EPA has no plans to pursue
private Site landowners, EPA may obtain information in the future under which EPA may pursue
such landowners on the Site.  For example, EPA may learn of a landowner who contaminated a
neighbor's property  (e.g., midnight, dumping).  Moreover, EPA may pursue any landowner who
learns of a release or threat of release after acguiring property, and then transfers the
property without disclosing this information.  Accordingly, EPA must make the following
reservation of its rights:  Nothing in this document constitutes, nor should be construed as,  a
covenant not to sue or waiver of prosecutive discretion concerning this matter.  In addition,
nothing in this document is intended to waive any rights the United States may have at law or in
eguity concerning the Tar Creek Superfund Site against any parties associated with the Site.

24.    Comment:   Are the O&M costs,  particularly the $60,000 shown for several of the
       alternatives,  a State cost?

Response:  Yes.   The O&M costs are costs to be borne by the State  (except on Indian lands).

25.    Comment:   When the work is completed on the properties,  will notices or restrictions be
       placed in the deeds?  Will notices or restrictions be placed in the deeds of properties of
       those who do not grant EPA permission to remediate their property?

Response:  The EPA can give a property owner a letter or certificate that states that the
property in question has been cleaned up, but EPA has no intention to place notices or
restrictions in the deeds of privately owned property.

26.    Comment:   Will test results be available somewhere like the county courthouse for review
       by interested persons?

Response:  The EPA will maintain the test results, identified by property location, at the Site
as long as EPA maintains a field office at the Site  (probably for at least six years).  At the
completion of the project, EPA will furnish the test results to the State and to the Bureau of
Indian Affairs.   The EPA will also maintain the test results at its offices in Dallas, Texas
until EPA's filing procedures call for the documents to be archived or destroyed.

27.    Comment:   What percentage of the owners of Indian land are not cooperating and allowing
       EPA access to conduct response activities?

Response:  The EPA has access to about 40% of the Indian land so far.  The Bureau of Indian
Affairs  (BIA) is continuing to assist EPA in obtaining access from the remaining owners of
Indian properties for the EPA response activities.  The EPA hopes to have access to most of the
properties by the time the remedial action begins.

28.    Comment:   Are the Indian properties included in the estimated 1,300 properties to be
       cleaned up under the remedial action?

Response:  Yes.   The EPA was able to get access to the Indian residential properties in order to
test them, and to determine the number needing remediation.

29.    Comment:   Do the 1,300 properties also include those properties for which access was not
-------
       granted?

Response:  Yes.  The 1,300 figure consists of the properties that were actually tested,  and it
also includes a portion of the untested properties that would reguire remediation.  The portion
of untested properties reguiring remediation is an estimate based on findings gathered from
tested properties located in the same area as the untested properties.

30.    Comment:  Will EPA continue to try to obtain access to properties that have not yet been
       sampled?

Response:  Yes.  However, once we complete the cleanup of the residential properties for which
we have access, we intend to demobilize the residential response contractors.  At that point we
intend to stop our efforts to obtain access to residential properties.

31.    Comment:  What will be the outcome of properties for the owner(s)  who do not grant access?

Response:  The EPA cannot clean up properties without first obtaining legal access.  We are
attempting to obtain voluntary access to all the residential properties.

32.    Comment:  Will water runoff from an adjacent property that is not cleaned up contaminate
       the cleaned up properties?

Response:  As properties are remediated, the drainage situation will be evaluated on a
case-by-case basis.  Grades will be sloped to drain away from residences.  Also, properties will
be graded to prevent or minimize any potential for runoff from adjacent properties to cause
recontamination.

33.    Comment:  How contaminated are lands along Tar Creek as a result of flood waters  that
       stand there for some time?

Response:  Sampling of lands in the Tar Creek flood plain to date, indicates that lead
concentrations caused by flooding are below the health-risk-derived level of 500 ppm.
Additional sampling is planned for the remedial action phase to further investigate the levels
of metals in the Tar Creek flood plain.

34.    Comment:  Why was not Miami included in the study area?

Response:  Miami was not included in the study area because it is not in the area which was
historically a mining area.  However, EPA's selected remedy will remediate areas in Ottawa
County (including Miami) which are located outside the mining area if those areas are found to
be contaminated with soil lead concentrations above the action level of 500 ppm.  The reason
that the study area included only parts of the mining area is that the degree of contamination
in the historical mining area is generally much greater than for areas outside the mining area
(including Miami), and because blood lead studies found much fewer children with elevated blood
lead in those areas outside the mining areas.

The blood lead survey conducted by the Oklahoma State Department of Health indicated that, for
the Miami area, the percentage of the target population (i.e., children 6 years old or less)
with elevated blood levels [i.e., blood lead concentration levels less than 10 micrograms per
deciliter (ug/dL)] is near the EPA goal of 5% or less.  Since the percentage of the target
population in Miami with elevated blood lead levels is relatively small and close to EPA' s 5%
goal, EPA expects that yard-soil excavation will generally not be reguired in Miami.  For the
smaller portion of the target population reported to have elevated blood lead levels in Miami,
compared to the larger portion of the target population reported to have elevated blood lead
-------
levels in the mining area, appropriate actions generally will include blood lead monitoring and
health education accompanied by some limited remediation of lead sources (e.g.,  vacuuming of
house dust with high-efficiency vacuum cleaners and covering or replacement of chat covered
traffic areas).

35.    Comment:   What is the percentage of children in Miami with elevated blood leads (i.e.,
       blood lead concentration levels greater than or egual to 10 ug/dL)?

Response:  The Oklahoma State Department of Health ((OSDH)  indicates that the percentage of
children in Miami with elevated blood lead levels is close to 5% based on limited screening.
OSDH has indicated plans to do a more comprehensive screening of the children in Miami.

36.    Comment:   How many of the residential properties owned by Indians,  actually have Indians
       living on them and how many have children living there?

Response:  The EPA does not have that information.

37.    Comment:   Is it not true,  that, if a residential property is contaminated,  that it does
       not make  any difference whether the residents are Indian or non-Indian with regard to
       which properties are cleaned up?

Response:  Correct.  The EPA's intent is to cleanup all the contaminated residential properties.

38.    Comment:   If the main obstacle to owners of the Indian lands granting access to EPA is
       concern about the liability for repayment of cost for remediation,  then why does not EPA
       waive this liability and any future cost reimbursements?

Response:  See response to guestion number 23 in this section of the Responsiveness Summary
[Section II(a)].

39.    Comment:   Will vacant residential lots be cleaned up?

Response:  Yes.   Vacant residential lots will be cleaned up, but they will be given a lower
priority than lots with people living on them.

40.    Comment:   Will information on how to deal with contaminated soil that is  disturbed below
       18-inches as a result of excavations, such as for utilities, be provided?

Response:  Information with regard to this subject will be provided as part of the health
education component of the remedy.  Also, a marker consisting of a geotextile fabric or other
suitable material will be placed in the bottom of excavations that reach the 18-inch depth.  The
marker will serve to alert the residents or others of the contamination remaining below.

b.     Written Comments from Citizen's Groups and the General Public

1.     Comment:   The EPA waived or did not include Community Protective Measures (CPMs) in the
       preferred alternative.

Response:  The comment is not correct.  Although CPMs are not the primary component of the
remedy they are included as a supplemental component in order to address uncertainties
associated with implementing the remedy such as inability to secure access to all
lead-contaminated residential properties.  CPMs are also included in the remedy to help address
lead contamination in communities in Ottawa County which do not have soil lead concentrations at
a level which warrants comprehensive yard excavation.
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2.     Comment:  Provide high efficiency particulate vacuum cleaners (HEPA VACs)  in every home
       remediated to protect future generations until all sources of lead and cadmium
       contaminated soil are eliminated.

Response:  HEPA VACs will be made available at no cost to local citizens.  A supply of HEPA VACs
will be made available at a central location(s) for check out.  Providing an adeguate supply of
HEPA VACs for time-shared use by the general public is much more cost effective than providing
HEPA VACs for every home.

3.     Comment:  Cardin and Picher are surrounded by chat piles and polluted water.  Drainage and
       wind blown dust from nonremediated areas will provide opportunity for recontamination of
       remediated yards.  Remediation of yards in those areas will not stop the lead and cadmium
       exposures to the populations of those towns until all chat piles are removed and the
       surface water cleaned up. The residents of Cardin and Picher should therefore be
       relocated.

Response:  Although, the residential yards in Cardin and Picher are more heavily contaminated
than the other communities in the area, this does not mean that the residential areas of Cardin
and Picher cannot be cleaned up to health protective levels.  Moreover, based on EPA air
monitoring, the potential that yards would become recontaminated by air deposition from chat
piles, from polluted water, or from other sources of lead or cadmium in the area is either
controllable or else it is not significant.  During the remediation of individual properties, if
it is determined that there is a significant potential for recontamination, for example from
surface water transport or even possibly from air deposition for specific properties, then
appropriate measures will be taken to prevent recontamination.  A list of measures to be used at
source areas to prevent recontamination is as follows:  (1) vegetating poorly vegetated or
unvegetated areas;  (2) capping with soil;  (3)  capping with base coarse material or paving  (4)
applying dust suppressants;  (5)  controlling drainage;  (6) consolidating source materials to
minimize recontamination potential; (7) containment of source materials; and (8)  abating lead
sources to prevent releases into the environment that would recontaminate remediated areas.
Also, to provide additional protection to the population, physical barriers  (e.g., fences and
warning signs) will be used, as appropriate, to restrict access to  mining waste which is
located near residences.  Due to the unigue nature each situation in which recontamination may
occur, it cannot be determined in advance which measures will be used; therefore,
recontamination prevention measures will be selected from the preceding list on a case-by-case
basis during the Remedial Action phase.  The EPA's experience at other lead-contaminated
residential areas has shown that the contaminated residential yards in Picher and Cardin can be
remediated and made safe for residential use.   Relocation is, therefore, not necessary.
Moreover, restoring the existing residential yards in Picher is more cost-effective than
relocation.

4.     Comment:  Tar Creek flows through the City of Miami and has,  on several occasions,  flooded
       nearby neighborhoods, parks and vacant  lots where children play.  Neighborhoods in the
       flood zone of Tar Creek should be studied.

Response:  Sampling along Tar Creek will be conducted to determine the risk in neighborhoods in
the flood zone as part of the residential response action selected in this ROD.  The Tar Creek
flood zone residential areas will be addressed as part of the remedial action.

5.     Comment:  If the contamination of Tar Creek is irreversible,  warning signs should be
       placed along the creek up to its entry into the Neosho River.

Response:  Warning signs would be an appropriate option, if it is determined that the
contamination in Tar Creek poses an unacceptable risk to humans.  Sampling of lands in the Tar
-------
Creek flood plain to date, indicates that lead concentrations caused by flooding are below the
health risk-derived level of 500 ppm.  Additional sampling along and in Tar Creek to be
conducted in the remedial action phase will further determine if levels pose a risk to humans.

6.     Comment:   Chat from the same chat piles that are of concern in the towns studied in the
       mining area were spread in Miami.  In the remedial investigation and feasibility study
       (RI/FS)  for residential areas, why was not the City of Miami studied?

Response:  See response to guestion 34 in Section II(a) of this Responsiveness Summary.

7.     Comment:   The RI/FS suggests eating locally grown produce could be a source of exposure to
       contamination.

Response:  Even though locally grown produce was investigated as a source of exposure, the
results of the investigation indicated that consumption of locally grown produce did not pose a
significant risk.

8.     Comment:   Are agricultural fields contaminated? Are cattle fish and other meat sources
       contaminated?

Response:  Agricultural areas and local fishing areas were not within the scope of the
residential area investigation.  These areas and concerns will be addressed in future
investigations.   Due to the size of the historical mining area, the primary lead-source area of
the Site—over 40 sguare miles, EPA has decided to divide the remediation of Operable Unit 2
into several phases.  The ROD is intended to address the residential phase of Operable Unit 2.
Other areas will be investigated in future actions.

9.     Comment:   The FS assumes that the soil from the remediated areas will be disposed of in
       dry mill  ponds where soil meets or exceeds the 500 ppm action level for lead.   What
       evidence  is there that mill ponds have been tested and that a proper site has been chosen?

Response:  The current disposal area near the old Eagle- Picher Central Mill site was an old
mill pond filled with tailings with lead levels in excess of 500 ppm based on EPA testing.
Plans are to use this same disposal area for the remedial action.  Any new dry mining waste
areas reguired for disposal will be investigated prior to disposal.  However, lead levels in
tailings in mill ponds, which would be the most likely candidates for disposal areas, typically
are much higher than 500 ppm lead.  The disposal area which EPA has selected is remote,
approximately 1  mile from the nearest residences.  The EPA will contour the soil in the disposal
area SO that erosion is minimal.  Moreover, the disposal area will be covered with a layer of
topsoil with lead levels below the 500 ppm remediation goal.

10.    Comment:   Provide assurances that proper caps, preferably clay,  then topsoil,  and then
       vegetation, will prevent transport of waste material from waste areas from wind erosion
       and surface water erosion of lead and cadmium.

Response:  The disposal area will also be capped with clean soil from a borrow source prior to
vegetating, unless the surface of the disposal area already has soil lead concentrations less
than 500 ppm.  (Soil excavated from the yards, generally in 6-inch layers, usually contains some
soil with lead concentrations less than 500 ppm. Concentrations greater that 500 ppm are reduced
as mixing  (during normal handling of the contaminated soil) occurs with lower concentration
soil.]  In addition, the final layer of soil covering the disposal area will be reguired to have
a sufficient clay content and will be reguired to readily support vegetation in order to prevent
the disposal area from being a source of wind-blown dust, and to prevent erosion from water.
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11.    Comment:   The Agency for Toxic Substances and Disease Registry (ATSDR)  1983-84 health
       assessment was conducted without the knowledge that is now available.   Direct involvement
       of ATSDR is recommended, including door-to-door surveys of the population to ascertain
       health information,  as well as traditional sources.  Studies of local  foods, including
       fish,  meats and wild game should be conducted.  The 1983 and 1984 assessments showed a
       need for a full health study.   It should be conducted, and serve to inform Superfund
       cleanup plans.

Response:  This comment recommended specific actions by ATSDR.  Therefore, EPA has furnished the
commenter's recommendations to ATSDR for its consideration.  The EPA believes that sufficient
data has already been developed to address the cleanup of contamination at the residential areas
of the Site.

12.    Comment:   If the chat piles are the major source of contaminants in the area,  why are they
       not being removed?  Exposures  in the community will continue until the chat piles are
       covered or removed.

Response:  The ROD calls for measures to prevent chat piles from recontaminating remediated
residential areas in situations where recontamination potential exists.  Except for these
situations, the ROD generaLly does not address chat piles because chat piles  are not within the
residential areas which are being addressed by the ROD.  The non- residential properties,
including the chat piles, will be addressed as a part of future response actions.  Removal of
the chat piles,  or covering the chat piles are among the options that will be considered in
future studies.

13.    Comment:   Why are the chat piles not classified as a hazardous waste?  Why are the chat
       piles  treated as a commodity rather than a waste?  Why are they not covered under the
       Resource Conservation and Recovery Act (RCRA)  via a permit with the local chat processor
       and asphalt companies?

Response:  See response to comment number 11 in Section II(a) of this Responsiveness Summary.

14.    Comment:   Not all areas where  children play have been remediated.

Response:  All children's play areas, including any High Access Areas not addressed by the
removal program, will be addressed in the residential response action selected in this ROD.
15.    Comment:   Three and four wheeler tracks are still visible on the chat piles and people
       still climb them.   As long as the chat piles exist,  the public should be prevented from
       entry and warning signs should be up.

Response:  The chat piles and associated problems will be addressed as part of the
non-residential area response actions.  As residential response actions are conducted, fences
and warning signs will be used as appropriate to restrict access to mining waste in proximity to
residential areas.

16.    Comment:   Warning signs should be used in unremediated public areas,  vacant lots and areas
       which show evidence of children's play or adult recreation.

Response:  All children's play areas and adult recreation areas within the residential areas
will be remediated including vacant lots.  Warning signs will be used as appropriate for
residential response actions and considered as an alternative in future response actions for
non-residential areas.
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17.    Comment:   The number of homes being remediated in this action does not match the amount of
       money allocated for the project.

Response:  Based on experience with average cost per yard for residential soil remediation, EPA
believes that the amount of money estimated for the project  ($29,440,840) is adeguate to address
the number of houses estimated (1,312).

18.    Comment:   With regard to Five Year Reviews,  in light of the other concerns at the Site not
       addressed by Alternative 2,  this  investigation should remain open.

Response:  There are future investigations planned for the Site to address remaining
contamination.  However, for the residential areas where lead contamination above the health-
risk-derived concentration level is removed, a Five-Year Review is not considered appropriate.
Five-Year Reviews will continue for other portions of the Site.

19.    Comment:   The water guality of the Neosho should be tested along with the fish,
       especially,  the popular sport fish, spoonbill,  white bass and catfish.

Response:  See response to guestion 7 in Section II(a) of this Responsiveness Summary.

20.    Comment:   Lead is a problem,  but  the other toxins are of egual concern,  and have many
       health risks associated with exposures.

Response:  With regard to human health,  EPA's risk assessment identified lead as the only
Site-related chemical of concern, and identified oral ingestion as the only significant route of
exposure.  Cadmium and zinc are also Site-related chemicals, but the concentrations in the
different media  (e.g., soil, air, drinking water) for cadmium and zinc were not high enough to
present a risk to  the population.   However, as lead is remediated, the other metals associated
with it in the soil will also be remediated.

21.    Comment:   The cleanup does not match the risk.

Response:  The risk from the Site is posed by the ingestion of lead contaminated soil.   The
selected remedy is an appropriate response for the identified risk and will remediate the lead
contaminated surface soil in the residential areas where it exists in concentration levels that
are above health-risk-derived concentration levels.

22.    Comment:   The millions spent on cleaning up yards in the most contaminated areas could be
       jeopardized by cave-ins which are continuing to occur.

Response:  When the mines were dewatered the freguency of cave-ins was greater.  The buoyancy of
the water now filling the mines has substantially increased the forces resisting cave-ins.  The
tendency for cave-ins is now greatly reduced.

23.    Comment:   No community-needs assessment has been conducted.  ATSDR needs to conduct a
       health consultation and health assessment.

Response:  This comment recommended specific actions by ATSDR.  Therefore, EPA has furnished the
commenter's recommendations to ATSDR for its consideration.  The EPA believes that sufficient
data has already been developed to address the cleanup of contamination at the residential areas
of the Site.

24.    Comment:   Northeastern Oklahoma ASM College has a walking trail, baseball field,  and
       football field that Tar Creek floods.  These areas have not been tested.
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Response:  Sampling of lands in the Tar Creek flood plain, to date, indicates that lead
concentrations caused by flooding are below the health-risk-derived concentration level of 500
ppm.  Additional sampling will take place during the remedial action phase in order to further
investigate the levels of metals in the Tar Creek flood plain.

25.    Comment:  Wildlife in the mined area includes deer and rabbits that are often consumed by
       residents.  With contamination of plants suspected, these animals feeding on the
       vegetation could pose a risk to consumers.

Response:  Investigating wildlife in the mined area was not within the scope of the residential
area investigation.  These areas and concerns will be addressed in future investigations.   Due
to the size of the historical mining area, the primary lead-source area of the Site—over 40
sguare miles, EPA has decided to divide the remediation into several phases.  The ROD is
intended to address the residential phase of Operable Unit 2.  Other areas will be investigated
in future actions.

26.    Comment:  Yards where children live are being targeted first.   With Ottawa County having
       such a high rate cf teen pregnancy, a home with no child now,  could easily have one soon.

Response:  Homes where pregnant women live are also a highest priority for EPA with regard to
scheduling yard cleanup work.

27.    Comment:  Tar Creek runs through the neighborhood and children still play in and around
       it.   Should we?  If it is dangerous,  who will warn us? Parents plant gardens in soil that
       has  been flooded with the water from Tar Creek.

Response:  Sampling of lands in the Tar Creek flood plain to  date, indicates that lead
concentrations caused by flooding are below the health-risk-derived level of 500 ppm.
Additional sampling is planned for the remedial action phase to further investigate the levels
of metals in the Tar Creek flood plain.

28.    Comment:  One of our members (Cherokee Volunteer Society)  has tested high in blood lead.
       The  yard and grandparent's yard were tested.   Who did those tests and will other yards in
       Miami be tested? When will the rest of our members be tested? Miami has been left out of
       health studies thus far.

Response:  As explained in the ROD, lead can be a serious health problem.  The blood lead level
of a person who has experienced elevated blood lead levels should be monitored on an ongoing
basis until levels are in the safe range.  Your associate should contact the Ottawa County
Health Department at 918-540-2481 or the Oklahoma State Department of Health at 405-271-4471 or
his or her family physician.  The EPA can also provide literature which explains how to avoid
lead contamination and how to deal with lead contamination in the home.  Contact the EPA Tar
Creek Field Office at 918-673-1173.

As explained above in our response to verbal comment 34, Miami lies outside of the heavily
contaminated mining areas.  Moreover, as explained in that response,  blood lead levels in Miami
have been found to b close to the range which EPA targets.  Accordingly, EPA expects that
yard-soil excavation will generally not be reguired in Miami.  For the smaller portion of the
target population reported to have elevated blood lead levels in Miami, compared to the larger
portion of the target population reported to have elevated blood lead levels in the mining area,
appropriate actions generally will include blood lead monitoring and health education
accompanied by some limited remediation of lead sources  (e.g., vacuuming of house dust with
high-efficiency vacuum cleaners and covering or replacement of chat covered traffic areas).
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29.    Comment:   A community protective measures (CPMs)  program should be implemented,  not in
       lieu of other cleanup strategies,  but as an important and integral component of  an effort
       to manage and abate lead exposure,  particularly from multiple sources.

Response:  Although CPMs are not the primary component of the remedy they are included  as a
supplemental component to address uncertainties associated with implementing the remedy such as
inability to secure access to all contaminated residential properties.  CPMs are also included
to address communities near the mining area where community- wide residential lead contaminated
yard-soil excavation is not considered appropriate.

c.     Written Comments from the State and Tribes

1.     Comment:   The Quapaw Tribe concurs with EPA's preferred remedy (Alternative #2)  as the
       most appropriate alternative and concurs with the residential soil lead remediation goal
       of 500 ppm.

Response:  The EPA acknowledges the Quapaw Tribe's concurrence with EPA's preferred remedy.

2.     Comment:   With regard to the Indian lands,  a comment by a representative of the  Quapaw
       Tribe stated that the Tribe is most concerned that EPA will not put into a contract that
       it will never try to recoup costs of remediation from the land owners or heirs.   The
       commenter also stated that an EPA representative had stated this policy,  but not in
       writing.   The commenter also expressed that assurance was needed in writing that the costs
       of EPA's response actions will never be borne by the allottees or their heirs.   The
       commenter also  stated that without this "guarantee" that the Tribe will be unable to
       advise its members to allow the remediation.  A representative of the Inter-Tribal
       Environmental Council of Oklahoma (ITEC)  also emphasized the need for written assurances
       to the Indian land owners that they will not be held liable for cleanup costs, to allay
       reluctance to grant access to EPA for response actions.

Response:  Please see Response to Comment 23 in Section II(a) of this Responsiveness Summary.
Please also see the Transcript of Public Meeting on Proposed Plan for the Tar Creek Superfund
Site, March 27,  1997, page 33.  The EPA is greatly concerned that it has been be unable to
obtain access to all Indian properties targeted for response actions.  The EPA is working
diligently along with the Bureau of Indian Affairs to try to resolve these issues.

3.     Comment:   A representative of the Quapaw Tribe recommended that the mining companies'
       Community Health Action and Monitoring Program (CHAMP) summary data (the conclusions and
       overall findings)  that were presented at the CHAMP meeting at the Picher Elementary
       School,  Picher,  Oklahoma on April 15,  1997,  should be made a part of or at least
       referenced in the Administrative Record.

Response:  The EPA was furnished a summary packet of the CHAMP data from a representative from
ITEC who attended the meeting.  The EPA has reviewed the summary packet and will include it in
the Administrative Record.

4.     Comment:   A representative of the Quapaw Tribe and a representative of ITEC made similar
       comments that the flood plain of Tar Creek in the Miami area should be tested as part of
       the response actions for the residential areas.

Response:  Additional sampling along Tar Creek will be conducted to determine areas of  potential
risk in neighborhoods in the flood plain as part of the residential response action.  The Tar
Creek flood plain area will be addressed as part of the remedial action.   The EPA does  note that
sampling of lands in the Tar Creek flood plain to date,  indicates that lead concentrations
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caused by flooding are below the health-risk-derived level for lead in soil of 500 ppm.

5.     Comment:   A representative of ITEC stated that if the flood plain is contaminated from the
       flooding of Tar Creek with metals above levels of concern,  that EPA should evaluate the
       use of constructed wetlands to control flooding and contaminant loading along the lower
       reaches of Tar Creek and that these actions should be included as part of the response
       actions for the residential areas.

Response:  If EPA determines that the levels of metals caused by the flooding poses an
unacceptable risk to the population living in the flood plain, then EPA will conduct appropriate
remediation as part of the response for the residential areas.  Also, if measures are needed to
prevent recontamination of any remediated areas in the flood plain, then EPA will also consider
alternatives, including constructed wetlands, to prevent possible recontamination.

6.     Comment:   A representative of ITEC, stated that the Quapaw Tribe is interested in the
       possible economic development of two non-residential Indian-owned properties (the former
       Eagle-Picher field office rite and the former Childress Chemical Company site)  located in
       Cardin, Oklahoma.  The commenter stated that timely remediation of these two properties
       will promote their economic development.

Response:  The EPA is also concerned that properties be remediated in a timely manner.  The EPA
is also sensitive to  the needs for economic redevelopment in the area.  Due to the scope of the
Tar Creek Superfund Site, all the possible remediation needed must be spaced out over time.  The
most important factor guiding prioritization of response actions at the Site is the sensitivity
of the human population exposed.  For this reason, the cleanup of the residential areas, which
are extensive, are being given priority over industrial areas and other areas.  The
non-residential properties, including the two properties referenced by the commenter,  will be
addressed later as part of the non-residential response actions.

7.     Comment:   A representative of the ITEC,  which is a consortium of 31 tribes in the State of
       Oklahoma,  stated that ITEC member Tribes favor EPA's preferred remedy (Alternative #2)
       with the 500 ppm soil lead action level.   The commenter stated that since it may not be
       possible for the EPA to obtain access to all of the Indian owned property, that at least
       some of the CPMs outlined in Alternative #3 will probably have to be included in the
       overall remedy.

Response:  The EPA acknowledges ITEC's support for EPA's preferred remedy.  Although CPMs are
not the primary component of the remedy, they are included as a supplemental component to
address uncertainties associated with implementing the remedy such as inability to secure access
to all lead-contaminated residential properties, and to address lead contamination in
communities in Ottawa County, particularly those outside the mining area where community-wide
residential lead contaminated yard-soil excavation is not considered appropriate.

8.     Comment:   With regard to the access to Indian land issue, a representative of ITEC stated
       that EPA,  the Bureau of Indian Affairs,  and Tribal governments should make efforts to
       educate reluctant property owners about the benefits of remediation on their neighbor's
       properties by hosting open houses and field trips to properties where remedial  work is in
       progress or has been completed.  The commenter also recommended that testimonials from
       owners satisfied with the remediation of their properties should also be included in these
       presentations.   The commenter also recommended that EPA,  BIA,  and the Tribal governments
       should publicize the favorable comments from residents and local government officials
       about the success of the residential response actions already being conducted under EPA's
       removal program.
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Response:  The EPA concurs with the need to educate reluctant property owners about the benefits
of remediation in an effort to encourage those individuals to grant access to EPA so that EPA
can conduct response actions.  The EPA and BIA are already undertaking considerable efforts in
this regard.  Specifically, EPA, BIA and DOI have entered into a memorandum of agreement
(January 1997) regarding efforts which will be made to secure access to Indian lands.  Under
this MOA, BIA and EPA officials are contacting each reluctant land owner over the telephone and
in person if possible.  We think that the commenter's ideas are good ones, and we will try to
incorporate them into our future actions as appropriate.

9.     Comment:   An ITEC representative asked if any  studies are being conducted,  or will be
       conducted,  to document the nature of any lead-related health problems among residents of
       the Site.   The commenter recommended that the  results of such studies,  past and present,
       be made known to the public.

Response:  The EPA's task under Superfund is generally to clean up uncontrolled releases of
hazardous substances that may pose a risk to human health or welfare or to the environment.
Whenever we can,  we hope to clean up hazardous substances before they cause health problems.
Accordingly, our investigations are generally targeted toward locating dangerous concentrations
of these materials.  We generally do not conduct health surveys as such, though sometimes that
data is helpful.   The EPA believes that sufficient data has already been developed for the
purpose of addressing the cleanup of contamination at the residential areas of the Site under
Superfund.  Results of health studies of metal contamination that are in EPA's possession are
placed, as a normal practice, in the Site repository at the Miami Public Library, Miami,
Oklahoma.  Only confidential portions of such health studies, like personal medical data, names,
or addresses, would be withheld to protect privacy.  Health studies, such as the commenter
refers to, are normally the purview of health agencies rather than EPA.  Therefore, EPA has
furnished the commenter's recommendations to ATSDR for its consideration.  The EPA is aware of,
though not a participant in, two lead exposure studies by the University of Oklahoma, Health
Sciences Center.   These two studies include monitoring of blood lead levels, but to EPA's
knowledge, they do not include investigation of other health problems or effects.  These two
studies are the recently completed CHAMP study which was funded by certain mining companies  (or
their successors),  and the Native American Lead Exposure Study, funded by National Institute of
Environmental Health, which is currently in progress.

10.    Comment:   The Oklahoma State Department of Environmental Quality (ODEQ)  concurs with EPA's
       preferred remedy (Alternative #2)  and concurs with the residential soil lead remediation
       goal of 500  ppm.

Response:  The EPA acknowledges the ODEQ's concurrence with EPA's preferred remedy.
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                                           TAR CREEK SUPERFUND SITE
                                           OTTAWA COUNTY,  OKLAHOMA
                                  RESPONSIVENESS SUMMARY, SECTION II, PART B

SUMMARY OF RESPONSES TO MAJOR COMMENTS RECEIVED DURING THE PUBLIC COMMENT PERIOD FOR THE
PROPOSED PLAN FOR THE RESIDENTIAL AREAS FROM MINING COMPANIES  (OR THEIR SUCCESSORS) THAT
FORMERLY OPERATED AT THE SITE, AND FROM THE U.S. DEPARTMENT OF THE INTERIOR

       The U.S.  Environmental Protection Agency (EPA)  received comments in a letter of May 22,
1997, from Gary D. Uphoff on behalf of ASARCO Inc., Blue Tee Corporation, Childress Royalty
Company, Inc., Gold Fields Mining Corporation, and the Doe Run Resources Corporation  (Uphoff,
May 22, 1997).  The EPA also received comments in a letter of May 9, 1997, from Lisa G. Esayian
on behalf of NL Industries, Inc.  These companies  (or their successors) formerly conducted
mining operations at the Tar Creek Superfund Site  (the "Site"), and are referred to collectively
in this document as the "Companies."  Comments were also received in a letter of May 15, 1997,
from Edward B. Cohen of the U.S. Department of the Interior (DOI, May 15, 1997).  This document
addresses the comments received from the Companies and the U.S. Department of the Interior
(DOI).  It should be noted that this document is only a part  (Part B) of the Responsiveness
Summary attached to the Record of Decision  (ROD) for the Tar Creek Superfund Site, Residential
Areas.  Another part (Part A) of the Responsiveness Summary addresses additional comments
received from other parties.

       After reviewing and assessing the comments provided by the Companies and DOI,  EPA has
determined that the comments do not provide any new information that would change EPA' s initial
determination, as set forth in the Proposed Plan, that the Preferred Alternative  (Alternative 2)
best meets the reguirements of the Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA)  and the National Contingency Plan, 40 CFR Part 300.  DOI and the
Companies, in their comments, have reguested or recommended that EPA perform certain additional
tasks.  These tasks are listed below.  The EPA's review of the comments submitted by DOI and the
Companies has found that the comments do not provide any significant information that supports
the performance of the following tasks as reguested or recommended by the Companies or DOI:

       S  Revising the Remedial Investigation  (RI) to include  other  data  on sources of  lead;
       S  Revising the Feasibility Study  (FS)to include  an additional  alternative  for detailed
          analysis;
       S  Revising the FS  to  include additional discussion of  Community Protective Measures
           (CPMs);
       S  Revising the Remedial Action Objective  (RAO);
       S  Obtaining additional  scientific data to  serve  as the basis for  remedy selection, or
          revising the existing scientific  data upon which remedy selection is based;
       S  Revising the FS  to  provide additional justification  for the  selected remedy;  and
       S  Selecting a remedial  action alternative  other  than  alternative  42 which  is  the
          Preferred Alternative described in the Proposed Plan.

       In their comments,  the Companies and DOI have recommended or reguested that EPA perform
the above list of additional actions.  The additional actions  are not warranted, and EPA's
position is supported by EPA's responses to comments provided below in this document.  The EPA's
responses address the significant issues raised by the Companies and DOI.

       The documents that EPA relied upon in preparing this response include without limitation
the following:
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Agency for Toxic Substances and Disease Registry  (ATSDR), 1995, Ottawa County Blood Lead Summary
 (informal), Memorandum from Jennifer Lyke  (ATSDR Region 6), December 18, 1995.

Bornschein, R.L., C.S. Clark, U.W. Pan et al., 1990, Midvale Community Lead Study, Department of
Environmental Health, University of Cincinnati Medical Center.

Centers for Disease Control, October 1991, Preventing Lead Poisoning in Young Children.

Chappell, W. et al.,  1990, Leadville Metals Exposure Study, Colorado Department of Health
 (Division of Disease Control and Environmental Epidemiology), University of Colorado at Denver
 (Center for Environmental Sciences), and U.S. Department of Health and Human Services
 (ATSDR/PHS).

Chrostowski, P.C. and J.A. Wheeler, 1992, A Comparison of the Integrated Uptake Biokinetic
Models to Traditional Risk Assessment Approaches for Environmental Lead, In:  Superfund Risk
Assessment in Soil Contamination Studies  (K.B. Hoddinott, ed.), ASTM STP 1158, American Society
for Testing and Materials, Philadelphia, pp. 151-166.

DOI, July 24, 1996,  Draft-Final Site Evaluation Findings Report, Tar Creek NPL Site, Oklahoma
City Field Area, Oklahoma, Report by C.C. Johnson & Malhotra, P.C. for the Bureau of Land
Management.

Hogan, K.A., R.W. Elias, A.H. Marcus, and P.O. White, 1995, Assessment of the U.S. EPA IEUBK
Model Prediction of Elevated Blood Lead Levels, The Toxicologist, Vol. 15, No. 1, pp. 36-37.

Malcoe, L.H., 1996,  Quarterly Report, CHAMP Program, July 1996-October 1996.

Malcoe, L.H., 1997,  Quarterly Report, CHAMP Program, January 1997-March 1997.

Malcoe, L.H., et al., April 15, 1997, Meeting Handout Data Summary, CHAMP Public Meeting, Picher
High School, Picher,  Oklahoma.

Renner, R., 1995, When is Lead a Health Risk?, Environmental Science & Technology, Vol. 229, No.
6, pp. 256-261.

Sedman, R.M. and R.J. Mahmood, 1994, Soil Ingestion by Children and Adults Reconsidered Using
the Results of Recent Tracer Studies, J. Air & Waste Manage. Assoc., Vol. 44, pp. 141-144.

Stanek, E.J. Ill and E.J. Calabrese, 1995, Daily Estimates of Soil Ingestion in Children,
Environmental Health Perspectives, Vol. 103, No. 3., pp. 276-285.

EPA, March 1990, Exposure Factors Handbook, Office of Health and Environmental Assessment

EPA, April 1992, Guidance for Data Useability in Risk Assessment  (Part A), Final

EPA, 1994a, Memorandum from Elliott P. Laws  (Assistant Administrator) to Regional Administrators
I-X, Re:  Revised Interim Soil Lead Guidance for CERCLA Sites and RCRA Corrective Action
Facilities, OSWER Directive # 9355.4-12, July 14, 1994.

EPA, 1994b, Validation Strategy for the Integrated Exposure Uptake Biokinetic Model for Lead in
children, Prepared by the Technical Review Workgroup for Lead, Office of Emergency and Remedial
Response, EPA 540/R-94-039.

EPA, 1994c, Guidance Manual for the Integrated Exposure Uptake Biokinetic Model for Lead in
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Children, Office of Emergency and Remedial Response, EPA/540/R-93/081.

EPA, April 1996, Urban Soil Lead Abatement Demonstration Project, Volume 1: EPA Integrated
Report

EPA, September 1996, Preliminary Remediation Goals, Residential Exposures, Tar Creek Superfund
Site, Ottawa County, Oklahoma

EPA Region 6,  (Revised July 10, 1996), Tar Creek Superfund Site, Technical Reply Document,
Residential Area Response Actions (Included as Attachment 2 to Section II, Part B of this
Responsiveness Summary)

EPA Region 6, May 15, 1997, Tar Creek Superfund Site, Detailed Response to Comments Received
During the Public Comment Period for the Removal Action for the Residential Areas (Included as
Attachment 1 to Section II, Part B of this Responsiveness Summary)

Uphoff, G.D., October 22, 1996, Comments on EPA's Removal Action on behalf of ASARCO Inc., Blue
Tee Corporation, Childress Royalty Company, Inc., Gold Fields Mining Corporation, and the Doe
Run Resources Corporation.

COMMENTS ON THE QUALITY OF THE DATA

1.     Comment:  The EPA's soil lead data for the Tar Creek Superfund Site are inconsistent with
       data previously collected at the two other mining related Superfund sites in the Tri-State
       Mining District, Cherokee County (Kansas) and Jasper County (Missouri).   Specifically,  the
       mine and milling wastes for all three sites should be similar,  since they are all part of
       the same geological ore deposit zone and they employed similar processing methods, yet the
       soil lead levels found in the Oklahoma portion of the district (i.e.,  the Site)  were
       significantly higher than in the Kansas and Missouri portions.

Response:  The wastes for all three sites are similar in most characteristics,  but there is
great variation in concentrations of lead in the various waste across the Tri-State Mining
District.  There is also considerable variability in the concentrations of lead in chat in the
piles around Picher.  The concentration in some of the chat found in Ottawa County is guite
sufficient to account for the lead concentration levels found in residential soil at the Tar
Creek Superfund Site.

2.     Comment:  The yard soil data collected by Ecology and Environment (E&E),  EPA's
       environmental engineering contractor,  at the Tar Creek Superfund Site are extremely biased
       and unrepresentative because of sampling and compositing procedures used.  The mean soil
       lead concentration for eight Picher residences reported by Dames & Moore (D&M),  an
       engineering consultant hired by the Companies (Uphoff,  October 22, 1996), based on their
       follow-up soil sampling investigation,  was less than half the mean soil lead concentration
       that was reported by E&E for the same properties.

Response:  The information provided in the comment is not correct.  The EPA has responded in
detail to a previous similar comment.  (See EPA Region 6, May 15, 1997:  Comment 41, and issue
"A" in the Response to Issues in the D&M,  Report.)  Briefly, the differences in soil lead
concentrations reported by E&E in the Tar Creek Superfund Site Residential Remedial
Investigation  (RI) and D&M in its follow-up study were due to differences in what was sampled,
not to bias or unrepresentativeness in E&E's sampling and compositing procedures.  The D&M
follow-up study samples included a much lower proportion of dripline samples.   Also, the D&M
samples were collected from a different depth than the E&E samples (0 to 2 inches for D&M versus
0 to 1 inch for E&E).  The soil sampling methodology used by E&E at the Tar Creek Superfund Site
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is commonly used at Superfund sites and is very similar to methodology that was used by D&M in
its investigation of the Jasper and Cherokee County portions of the Tri-State Mining District.

3.     Comment:   The EPA's estimates of average yard soil concentrations were biased because the
       individual strata were not weighted by relative stratum size.   [The term stratum as used
       by the commenter is a physically defined area (e.g.,  frontyard,  backyard,  or driveway)
       that was  sampled and is consistent with EPA usage in the sampling design (EPA,  April 1992,
       Exhibit 44).]

Response:  The EPA typically uses the arithmetic average concentration of a contaminant within
an exposure area to estimate exposure based on the assumption that contact with the contaminant
anywhere in the exposure area is egually likely.  This is a useful and reasonable default
assumption.

In deriving an estimate of long-term exposure point concentrations, two important factors that
will affect exposure to soil contaminants, other than the relative size of an area, are the
amount of time a receptor spends in different portions of an exposure area and the accessibility
of the contaminants in those areas.  For example,  a child might spend more time in a small play
area, like a swing set, a sandbox, or a driveway,  than in a large front yard.  The presence or
absence of ground cover also affects the accessibility of soil contaminants.  Front yard and
back yard areas are usually covered with grass which reduces a receptor's contact with the soil
in those areas and reduces the amount of soil tracked into the house from those areas.  Thus an
area weighted average concentration does not necessarily provide the best estimate of exposure
to yard contaminants.

4.     Comment:   Appropriate stratum weights for obtaining an unbiased estimate of the lot
       average concentrations cannot be derived from the relative stratum areas alone, but should
       also be based upon the relative proportion of fine material in the soil.

Response:  An additional weighting factor based on the amount of fine material in a stratum does
not necessarily provide a better estimate of exposure to soil contaminants.  As already noted,
the presence or absence of ground cover may greatly affect the accessibility to soil
contaminants.  Exposure to soil from a lawn-covered yard area, with a higher fraction of fine
material, could be less than from an unpaved driveway.  The soil sampling program used by EPA
for the Tar Creek Superfund Site has been commonly employed by EPA at other sites with favorable
results.

5.     Comment:   As documented in the "Review of the Soil Sampling Approach ..." by Key
       Environmental (Uphoff,  May 22,  1997,  Attachment 1),  the individual stratum means were
       themselves biased.

Response:  The main thrust of the discussions about stratum average estimates in Attachment 1 is
that the variability of contaminant concentrations within each stratum has not been defined and
that the number of samples and the amount of material collected per sample may not be sufficient
to capture the full range of variability that may exist in these areas and that failure to
capture all of the variability could lead to concentration estimates that are not perfectly
representative of the area  (i.e., that may not have captured all of the variability - not that
they deliberately misrepresent the true concentrations).

The commenters have not provided any evidence that these hypothetical issues have had any real
effect on the data in this case or shown what the magnitude of any effect might be.  Neither
have the commenters shown that their recommended methods would significantly improve the
accuracy of the estimates of potential exposure to soil contaminants to justify the additional
time and expense.  That is, although the issues raised in this comment have only recently
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emerged in the arena of environmental sampling, and were not addressed in the EPA sampling
guidance documents available when the Tar Creek Sampling Plan was being developed, the
commenters have provided no evidence that the hypothetical issues raised would have any real
effect on the data gathered at the Site.

6.     Comment:   A previous EPA response that "any reasonable weighted average is likely to be
       numerically similar (+ or -10 to 20%)  to the simple average" is without justification.

Response:  The EPA statement was based on comparison of the simple average of the average
concentrations measured in the various subareas investigated with weighted averages based on
several different weighting schemes.  Accordingly, the different weighing schemes produced
similar numerical results.

7.     Comment:   Exclusion of the garden areas from the property average effectively assigned a
       weighting factor of zero to garden soil.

Response:  As explained in the BHHRA, exclusion of garden soil from the property average was
based on an exposure assessment decision that direct contact with garden soil was not likely  to
be a complete exposure pathway for young children.  For this reason, it did not assign such a
weighting factor.

8.     Comment:   It cannot be determined whether the sampling design provided sufficient data for
       remedial decision making in accordance with EPA guidelines.

Response:  Before the start of the residential soil sampling program for the Tar Creek Superfund
Site, some 1,500 samples were collected from High Access Areas in the Study Area and analyzed
for lead.  These samples were log normally distributed and the log transformed results had a
coefficient of variation  (CV) of 25.4%.

According to EPA guidance, which is consistent with generally accepted scientific practice, the
minimum statistical performance reguired for risk assessment is a confidence level of 80%,
statistical power of 90%, and a minimum detectable relative difference  (MDRD) of 10% to 20%.
With a coefficient of variation of 25%, 29 samples would be reguired to achieve a MDRD of 10%
and 8 samples would be reguired for a MDRD of 20%.  The average yard soil concentrations for
individual properties were based on 15 to 25 separate soil aliguots depending on whether a
driveway and a play area existed at a property.  Therefore it appears that the residential
sampling program provided data of sufficient guality for risk assessment purposes even at
individual residential properties.  However,  no statistical inferences were based on sampling
results for individual properties.  The decision about whether remedial measures were reguired
was based primarily on the predicted risk of blood lead levels greater than 10 micrograms per
deciliter (ug/dL) for the Study Group Homes as a group.  This estimate of community risk was
based on more than 400 composite soil samples and more than 2,000 separate soil aliguots, many
more than were needed to ensure adeguate data guality for risk assessment purposes.

9.     Comment:   The soil sampling procedure described in the Remedial Investigation Report
       (Brown and Root 1997)   indicates an error in the selection of sampling locations: "Sampled
       locations included those areas deemed by the sampling team as being obvious signs of
       chat."

Response:  The statement in the RI Report prepared by Brown and Root has been misinterpreted.
Locations showing obvious signs of chat may have been included among locations sampled; however,
such locations were neither deliberately selected nor were they avoided because of the presence
of chat.   The sampling plan,  which was developed and carried out by E&E, was neutral with
respect to chat, neither deliberately selecting nor deselecting locations exhibiting signs of
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chat.  The statement quoted from the Brown and Root RI Report appears nowhere in E&E's Sampling
Plan, Data Evaluation Summary Report, or Baseline Human Health Risk Assessment Report.

10.    Comment:   Drying the soil samples prior to particle size fractionation by sieving may have
       introduced sample preparation error by altering the physical size distribution from that
       found in situ.

Response:  Particle size fractionation was accomplished using gravity and mechanical agitation
of the sieve.  Some minor incidental drying may have occurred during these processes.  However
no significant sample preparation error was introduced by the size fraction process, because any
particle size reduction as a result of the drying accompanying soil sample preparation is not
likely to have been significantly more than the size reduction that already occurred naturally
as a result of repeated wetting and drying cycles and weathering forces in nature.

11.    Comment:   It would be interesting to assess the decision error risks associated with the
       use of as few as 15 sites sampled in the Reference Area.

Response:  The comment has inadequate basis.  The EPA's decision as to whether remedial measures
were required was based primarily on comparison of the blood lead levels predicted for current
and future residents of the Study Group homes to EPA's lead exposure management goal  (EPA1 s goal
is that a typical child or group of similarly exposed children should have no more than a 5%
chance of having a blood lead level greater than 10 ug/dL),  not on a comparison of predicted
blood lead for residents of Study Group and Reference Area homes.  The Reference Area was used
to help EPA evaluate the effect of lead exposures unrelated to mining wastes on predicted blood
lead levels, not as a basis for EPA's decision to take remedial measures.

12.    Comment:   There was too great a difference in the number of samples collected from the
       Reference Area (15)  and the Study Area (>1900)  to justify comparison of the two data sets.

Response:  The Reference Area was established primarily to provide a reference data set for
comparison with the Study Group data set that included 100 residences, not for comparison with
all of the more than 2,000 residences in the Study Area as a whole.  When formal statistical
comparisons were made between the contaminant concentrations in various environmental media from
the two areas (i.e., the 100 compared to the 15), well established statistical methods,
including t- tests and Mann-Whitney U-tests that take sample size differences into account, were
used.

13.    Comment:   It is not clear that the Reference Area was selected in accordance with EPA
       guidance which indicates that a reference area should not differ from a cleanup area in
       physical,  chemical,  or biological characteristics.  The Reference Area for the Tar Creek
       Superfund Site was selected based on its similarity to Picher with respect to the
       characteristics of its housing stock.

Response:  The main purpose of the Reference Area was to help EPA evaluate the effect of lead
exposure factors other than exposure to mining related wastes on predicted blood lead levels.
Therefore, the main requirements for the Reference Area were that it be outside of the mining
area, and have housing stock similar to that in the mining area to control for possible lead
paint exposure.   The chosen Reference Area fulfilled these main requirements because it is
outside the mining area, but contains homes which are similar to the homes in the mining area
with respect to age, type, and size—primary factors in determining the likelihood of lead paint
contamination.

14.    Comment:   The  soil particle size fractionation methods used in preparing samples for
       analysis may have biased EPA's selection of an action level and the Preferred Remedial
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       Alternative.  The minus-250 micron fraction does not provide an appropriate basis for
       selection of Preliminary Remedial Goals or remedial alternatives.

Response:  The EPA selected the remedial goals, action levels and remedial alternatives for the
Tar Creek Superfund Site utilizing blood lead levels predicted by the IEUBK model.  The soil
samples used as input to the IEUBK model were prepared in accordance with EPA Region 6's
standard procedures which include sieving the samples through a 60-mesh screen.  The minus
60-mesh fraction includes particles approximately 250 microns in size or smaller and is the
fraction most likely to adhere to the skin and be ingested through hand-to-mouth contact.  Since
ingestion is of primary concern, this screening method is appropriate.  The EPA Technical Review
Workgroup for Lead recommends that lead concentrations measured in this fraction of soil be used
in the IEUBK model because it is the fraction most likely to adhere to the hands of a small
child and be ingested.  Therefore, it was entirely appropriate to base remedial decisions on
this soil particle size fraction.

15.    Comment:   Comparison of soil lead results obtained by X-ray fluorescence (XRF)  for the
       minus 10-mesh fraction with results obtained by EPA Contract Lab Program (CLP)  methods for
       the minus 60-mesh fraction is inaccurate and inappropriate.

Response:  Because of the large number of samples that needed to be analyzed and the rapid
turnaround reguired, it was necessary to analyze most of the soil samples collected by XRF.  The
empirical relationship between the XRF and CLP results was determined by linear regression
analysis on the log-transformed data, and the regression eguation was used to convert the XRF
concentrations to the corresponding CLP values.

The p-value for the slope of the regression eguation  (the probability that the observed
correlation is a statistically rare occurrence) was less than 0.0005 and the data were uniformly
distributed from high to low.  These results indicate that the correlation was very strong.
However, there was some scatter about the regression line due to measurement errors associated
with both the XRF and CLP data.  Because the linear regression is based on log-transformed data,
back transformation magnifies the scatter.  The regression line predicts for any given XRF
concentration, log-transformed, the expected value of the log of the CLP concentrations  (which
would be the average over many trials).   However, because of measurement errors, individual
observed values from the CLP data may differ from the predictions.   That does not mean that the
regression eguation is wrong.

COMMENTS ON LEAD SOURCES OTHER THAN MINING WASTE

16.    Comment:   Paint is a primary contributor of lead to Site soil based on the large
       proportion of older homes in Picher with peeling exterior lead-based paint, the higher
       lead  concentrations in dripline  soil compared to other soil strata,  and the presence of
       soil lead levels similar to those found at the Tar Creek Superfund Site in older urban
       areas where lead-based paint is  the primary source of lead.

Response:  The EPA has responded to these points when they were made in previous similar
comments.   (See EPA Region 6, May 15, 1997:  Comment 20, and issue f in the Response to Issues
in the D&M Report.) The EPA acknowledges that lead-based paint may be an important source of
lead at some residences; however, the weight of evidence indicates that lead-based paint is not
the primary source of the elevated soil lead levels found at most of the residential properties
in Picher.  While lead levels at drip lines tended to be higher than in other yard areas, they
were substantially higher at fewer than 20% of Study Group homes.  Furthermore, the available
paint chip data show no discernable difference in the prevalence of lead-based paint between the
Study Group and Reference Area homes; therefore, paint cannot account for the order of magnitude
difference in soil lead concentrations between the two areas.  Moreover,  the risk from yard soil
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containing lead-contaminated mining waste is, by itself, enough to warrant cleanup of that soil
as called for in the ROD.

17.    Comment:   Lead speciation analyses conducted by Dr.  Burke Burkart for EPA and Dr.  John
       Drexler for DOI indicated that the primary sources of lead in residential soil at  the Site
       were paint and smelter wastes.  The results of the analyses by Burkart and Drexler are
       discussed in a report prepared by Geomega (Uphoff, May,  22, 1997, Attachment 2), which
       also presents new data for 4 waste samples from the Hockerville smelter and 3 samples from
       chat piles.  According to Geomega's report,  the forms of lead found in the smelter waste
       are identical to the forms identified in yard soil from Picher, and this confirms  that
       smelter wastes are the principal source of lead in the soil.  Further the lead content of
       the smelter wastes,  in the 2 to 7 percent range,  can credibly explain the lead
       concentrations in residential soil at the Site.  Also, the DOI electron microprobe
       analysis indicates that up to 66 percent of the lead in residential soil is attributable
       to smelter emissions.  It also indicates that lead paint may contribute up to 17 percent
       of lead in soil at the Site.  The microprobe work is described in DOI's report titled
       "Draft Final Site Evaluation Findings Report, Tar Creek NPL Site" dated July 24,  1996.

Response:  Previous EPA responses have addressed similar comments with regard to the Burkart and
Drexler reports.  (See EPA Region 6, May 15, 1997:  Comment 29,  and issue e in the Response to
Issues in the D&M Report.)

The figures for paint and smelter emission contributions to soil lead are misleading.  The 17
percent figure for paint is the mean of the paint percentages listed for soil samples in Table
4.5.2.1 of DOI's report  (DOI, July 24, 1996) based on Drexler's electron microprobe results.
For three of the soil samples (044, 379, and 502),  the bulk of the "Paint" Percentage shown in
the table was actually reported by Drexler as "cerussite (paint?)," which meant that the  source
of the cerussite could not be identified but that paint was a possible source.  Cerussite is
also a weathering product of galena, which is often found in chat.  Cerussite was positively
attributed to paint in only one soil sample  (396).   The 66 percent figure for smelter emissions,
which also comes from the soil results in Table 4.5.2.1., is the mean percentage of lead
reported as Pb(M)0 and Mn/FePbO. However, the lead in Mn/FePbO is not necessarily related to
smelter emissions.  Moreover, MnPbO and FePbO are secondary weathering products formed in soil
when soluble lead compounds react with iron and manganese oxides that are naturally present in
soil, so they are not necessarily due to smelter emissions either.

The findings of the Geomega Report are not a "finger print" for smelter waste as the comment
implies.  The Geomega Report, states in a discussion of two of the four smelter waste samples
from Hockerville that "Lead was  present as lead (metal) oxides and antimony  (metal) oxides
phases identical to those identified in yard soils in the in the 1996 Drexler report,
corroborating the conclusion that there is a substantive contribution of smelter lead to  the
lead pool in the residential yards."  The EPA acknowledges that lead(metal)oxides were
identified in the soil samples analyzed, along with a number of other lead mineral forms.
However, the mere presence of lead(metal)oxides does not prove that smelters are the principal
source of lead in the soil.  Lead  (metal) oxides have not been proven to be a "finger print" of
smelter waste.

No smelter has been identified that could account for  the lead levels found in soil at  the Tar
Creek Superfund Site.  The Ontario Smelting Company smelter near Hockerville is the only smelter
known to have operated on the Site.  It was located 3 miles east of Picher in a generally
crosswind or downwind direction under prevailing wind conditions, too far away to account for
the soil lead levels found in Picher soil.  Furthermore, the highest soil lead concentrations
were generally found in Picher and Cardin.  There is no evidence of an area-wide gradient in
soil lead concentrations centered on the Hockerville smelter that would be expected if emissions
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from that smelter were a major source of soil lead levels in the Study Area and particularly in
Picher and Cardin, the areas most affected by lead contamination.

Historical information on the Tri-State Mining District indicates that there was a much greater
concentration of large central milling operations in the Picher/Cardin area than there was
elsewhere in the Tri-State Mining District.  The size and abundance of former and existing chat
piles in the Picher/Cardin area testify to this fact.  The evidence shows that various releases,
fugitive emissions, and wastes associated with the historical mining and ore processing
operations were the major source of the elevated soil lead levels found in the Site area.

18.    Comment:   Omission of data concerning the potential sources of lead undermines the
       validity and reliability of the RI,  Baseline Human Health Risk Assessment (BHHRA), the
       Feasibility Study (FS),  and the remedy selection.   The commenter repeatedly identifies the
       lead speciation data as the primary omission.

Response:  The comment has no basis.  No significant and reliable data on sources of lead were
omitted.  The RI, BHHRA, and FS contain sufficient reliable data which indicate that the lead
contamination in the residential soil is primarily from mining waste.  As explained above in our
response to question number 17, the speciation data to which the commenter refers are
inconclusive as far as the identification of the sources of lead in the mining area soil is
concerned.  It should be noted that the speciation data have been considered by EPA, and they
are included in the Administrative Record File for the Site.

19.    Comment:   DOI and EPA have confirmatory information on three historic smelters that
       existed in the Picher area.

Response:  The Ontario Smelting Company smelter near Hockerville is the only smelter confirmed
to have operated on the Site (See Response to Comment 17 above).  Information about the two
other reputed smelter locations was apparently drawn from  a DOI database.  However, the
locations identified  are not confirmed locations of significant former smelter operations.
There are no historical records or other data demonstrating significant smelting in the
Picher/Cardin area.

COMMENTS ON THE IEUBK MODEL AND ITS APPLICATION AT THE SITE

20.    Comment:   The IEUBK model is flawed and,  in its current form,  does not provide a reliable
       and accurate basis for making decisions about children's  health.

Response:  The IEUBK model is the best tool currently available for assessing blood lead levels
in children (EPA 1994a) and a good predictor of potential long-term blood lead levels for
children in residential settings.  The model has received extensive peer review from both the
Science Advisory Board and the Technical Review Workgroup for Lead.  In July of 1992, the Office
of Solid Waste and Remedial Response  (OSWER) convened a meeting to solicit comments on the
original Uptake/Biokinetic  (UBK) model from a wide range of interests, including environmental
groups, citizens, and lead industry representatives,  and incorporated comments from these groups
into the current IEUBK model.

In 1994, EPA outlined its strategy for IEUBK model validation (EPA 1994b).  Initial results of
the validation effort were reported at the 1995 Society of Toxicology meeting by EPA
representatives  (Hogan et al. 1995) .  Validation was carried out with existing data sets
relating environmental and blood lead levels on a per individual basis by using the IEUBK model
to generate blood lead predictions from the measured environmental lead levels.  These predicted
lead levels were then compared with the measured blood levels, using geometric mean blood levels
and proportions observed or expected to have elevated blood lead levels.  All studies used for
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the validation exercise had data of sufficient quality and quantity to characterize the
environmental lead levels in each residential home and yard  (i.e., blood lead levels of
residents, as well as soil, dust, water, interior and exterior lead paint levels, and
demoqraphic/behavioral survey data coverinq other aspects of lead exposure).   The modeled
results and observed blood lead levels were reasonably concordant, with similar qeometric mean
predicted and observed blood lead concentrations  (5.81 uq/dL versus 5.44 uq/dL, respectively)
and similar population proportions with elevated blood lead levels (Renner 1995).

Comparisons of IEUBK model output to empirical blood lead data can contribute to an overall
evaluation of the credibility of model predictions (EPA 1994b) .   Results of EPA's validation
exercises provide confidence that the IEUBK model is a credible predictor of blood lead levels
in environmentally exposed children.

21.    Comment:   The IEUBK model overestimates the impact of lead in soil on blood lead levels.
       The model overestimates absorption rates and inqestion rates.   As a result,  it
       overestimates exposure and predicts hiqher blood lead levels than are observed in
       communities.

Response:  The commenter cites examples of other sites where the blood lead levels predicted by
the IEUBK model were hiqher than the observed blood lead levels, possibly due to overestimates
of the inqestion rates and/or absorption rates for lead in Site soil.  However, the commenter
has not shown that lead exposures or risks of elevated blood lead levels were overestimated for
younq children in the Study Group homes at the Tar Creek Superfund Site.  In fact,  the available
evidence suqqests otherwise.  That is, blood lead data qathered on the Site has been consistent
with IEUBK predictions.

       It is unlikely that lead exposure from soil inqestion has been overestimated at the Site.
Considerinq the relatively warm climate on the Site (which encouraqes outdoor play and the
ensuinq soil exposure), there is no reason to expect that soil/dust inqestion rates at the Site
would be lower than model default values, which are based on estimates of averaqe inqestion
rates for national application.  Similarly, the results from EPA Reqion VIII's study of
bioavailability of lead in soil from the Jasper County, Missouri Superfund Site  (Casteel et al.
1996) indicate that the 30% model default value for absorption of lead is at the low end of
bioavailabilities (29 to 40%) measured for lead in soil from the Jasper County portion of the
Tri-State Mininq District.

Additionally, the observed blood lead data do not indicate that the model has over predicted
blood lead levels.  Results from the 1995 Oklahoma State Department of Health  (OSDH) blood lead
survey in Picher, where the Study Group is located, indicated that 10 of 48 (21%) tested
children aqe 6 years or less had blood lead concentrations qreater than 10 uq/dL.  That
percentaqe was consistent with community risk predictions Of the IEUBK model which were based on
soil, house dust, homeqrown produce, and tap water from Study Group homes.

A quarterly report  (Malcoe, 1996) prepared at the request of the Companies by the University of
Oklahoma as part of the Companies' Community Health Action and Monitorinq Proqram (CHAMP)
indicates that blood lead levels in younq children from Picher are even qreater than those
reported by OSDH.  In the first quarterly survey  (July-October 1996;  Malcoe 1996),  it is
reported that 38.3% of the 81 children tested in Picher  (31 children) had blood lead levels
qreater than or equal to 10 uq/dL, and 13.6% had blood lead concentrations qreater than or equal
to 15 uq/dL.  For comparison, this study indicated that, in the latest  (1988-1991)  United States
population study of blood lead levels in children, only 8.9% of children 1 to 5 years old had a
blood lead concentration qreater that 9 uq/dL, and only 2.7% had a blood lead concentration
qreater than 14 uq/dL.  The hiqh percentaqes of elevated blood lead levels at the Site reported
in the CHAMP quarterly report compares to the 2% of the qeneral Oklahoma population with blood
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lead levels greater than 10 ug/dL (Malcoe et al.,  April 15,  1997) .

The CHAMP blood lead survey indicates that the model predictions may have underestimated,  rather
than overestimated, actual blood lead concentrations in Picher children.   The higher observed
blood lead levels are not inconsistent with the model predictions,  as they may reflect
additional exposures to lead from paint or other sources that the IEUBK model did not account
for.  The possibility of additional exposures to lead from other sources does not reduce the
risks posed by lead in Site soil.

22.    Comment:   Reduction in soil lead levels leads,  at best,  to a small reduction in blood lead
       levels.   The EPA's "Three Cities Study" found no reduction in blood lead levels in
       Baltimore and Cincinnati following soil remediation and a reduction of only 1 ug/dL per
       1000 parts per million (ppm)  lead in soil  in Boston.   Also,  at the Bingham Creek mining
       waste site,  a 0.6 ug/dL increase in blood lead was observed between 100 and 1,100 ppm lead
       in soil,  and a smaller blood lead increase  was observed at higher soil lead levels.

Response:  The Three Cities Study Integrated Report (EPA April 1996) concluded that "(w)hen soil
is a significant source of lead in the child's environment,  under certain conditions, the
abatement of that soil will result in a reduction in exposure that will cause a reduction  in
childhood blood lead concentrations."  The seemingly small reduction of blood lead levels  from
reducing soil lead levels in the studies cited in the comment may not be directly comparable to
the Tar Creek Superfund Site because of site-specific differences.   The weak relationship
between soil lead concentrations and blood lead levels in the studies cited may reflect the
presence of other significant sources of lead exposure for children, relatively low
bioavailability of lead in the soil, or other important site-specific differences.  However, it
should be recognized that any environmental lead abatement may be limited in its ability to
guickly reduce blood lead concentrations in currently lead burdened children because blood lead
levels reflect not just recent exposure, but also lead from accumulated body stores, which can
be released to the blood.  See Response to Comment 24 below.

23.    Comment:   The observed reductions in blood  lead levels in the Boston Study portion  of the
       Three Cities Study may be due to the general,  national downward trend as well as natural
       reduction as a child gets older, rather than to soil   remediation.

Response:  The reported decline in blood lead levels associated with soil abatement in the
Boston study is based on a comparison of a Study Group and a Control Group.  The national  trend
cited would presumably effect both groups, therefore,  they cannot explain the Study Group
results.

24.    Comment:   The IEUBK model predicts a reduction of at  least 3 to 6 ug/dL in the geometric
       mean blood level for each 1000 ppm in soil  that is removed.   Such dramatic reductions have
       not been achieved from soil remediation.

Response:  Reductions in elevated blood lead levels may not be as great in the short-term as the
IEUBK model predictions suggest, because the model does not take into account the existing body
burden of lead resulting from previous exposures.   Lead levels in the blood reflect not only
recent exposures, but also the lead from accumulated body stores in bone and other tissues,
which can be released by biokinetic processes to the blood.   Because of this release from
internal sources, there may be a component of blood lead levels in children that responds  only
slowly to any changes in environmental lead exposure.   In the first year or two after abatement,
this internal source of lead may cause a moderately elevated blood lead level to persist in a
child.  The effectiveness of lead abatement should not be evaluated only in terms of reducing
existing high blood lead levels, but also in preventing future exposures and reducing risks of
elevated blood lead levels in future residents.
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25.    Comment:  The relationship between soil lead and blood lead ranges from nonexistent to
       weak.  The commenter cites a number of studies of other sites in support.

Response:  Reliable blood lead data are difficult to obtain, and the interpretation of the
results is also often difficult because of small sample sizes and other confounding factors.
Also, for a given site, soil may not be the main source contributing to increases in blood lead
levels.  Even at sites with very high soil lead concentrations, soil may not be the major
contributor to blood lead if the bioavailability of the lead in soil is low.  However, neither
of these circumstances appears to apply at the Tar Creek Superfund Site.

26.    Comment:  Because of other sources that overwhelm the contribution from soil and because
       of the weak relationship between soil lead and blood lead,  it is not clear that soil
       remediation will result in any observable reduction in blood lead.

Response:  The commenter has not demonstrated that either premise applies to the Tar Creek
Superfund Site.

27.    Comment:  Blood lead levels continue to decline nationwide in the absence of soil
       remediation,  and this downward trend is observed at mining sites and other lead related
       sites.

Response:  The EPA has responded to a previous similar comment.  (See EPA Region 6, May 15,
1997:  Comment 5.)

28.    Comment:  The IEUBK model has known errors in its absorption component.   In the model,
       absorption of lead from food, water, soil, and dust actually increases as the child gets
       older, rather than decreases as would be expected.

Response:  The IEUBK model calculates lead absorption from the gut as a function of two
components, a passive component and an active component.  The coefficient for passive absorption
remains constant.  However, the active component is affected by the concentration of lead in the
gastrointestinal (GI) tract, that is, the coefficient for active absorption decreases as the
lead concentration increases.  The lead concentration in the GI tract depends on both the intake
of lead and the GI volume, which is age dependent.  As the child gets older, the GI volume
increases, the lead concentration for any given intake decreases,  and the coefficient of active
absorption increases.  Thus, when the lead intake rate is held constant, the total mass of lead
taken up increases slightly with age, but when adjusted for the child's increasing body weight,
the mass taken up per kilogram of body weight decreases as expected.

29.    Comment:  The IEUBK model probably overestimates soil ingestion rates; community-wide soil
       ingestion rates may vary substantially from the model assumptions.  For example,  in the
       risk assessment for California Gulch,  Leadville, CO,  EPA estimated soil ingestion rates to
       be about 40 percent of the IEUBK values based on the results of regression analysis of the
       soil lead and blood lead data.

Response:  The EPA Exposure Factors Handbook  (EPA March 1990) and the IEUBK Guidance Manual  (EPA
1994c)  reviewed soil ingestion rate data from a variety of sources and based their default
ingestion rate recommendations on the weight of evidence that emerged from that broad based
literature review.   The EPA recognizes that there is uncertainty associated with the use of
default soil ingestion rates in the IEUBK model, and acknowledged as much in the BHHRA report.
However, there is no evidence that soil ingestion rates at the Tar Creek Superfund Site are
significantly lower than the default rates.  Ingestion rates estimated for the Leadville site
are likely not applicable for the Tar Creek Superfund Site due to different conditions at
Leadville  (e.g., appreciable snow cover which may prevent soil contact for part of the year or
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other site-specific factors).

30.    Comment:   Food lead intake rates are much lower than the IEUBK Model default rates,  which
       are based on the 1986-1988 FDA Total Diet Study.   The 1991 average dietary intakes of
       children two years old  and infants 6-11 months old were 1.87 ug/day and 1.82 ug/day,
       respectively,  much lower than the model default rates (Bolger 1996).  Because dietary lead
       is overestimated,  the remedial soil lead level predicted by the IEUBK model is lower than
       it should be.

Response:  The 1991 intake rates reported by Bolger  (1996), which were not available when the
risk assessment was prepared in 1995, indicates that dietary lead intake has dropped noticeably
since 1988, which suggests that the model default values for diet may be high.  However,  the
Technical Review Workgroup for Lead has not completed its evaluation of the most recent data
from the FDA Total Diet Study.  Therefore, EPA Region 6 will rely on the model default values.

31.    Comment:   The IEUBK model does not completely or accurately account for paint exposure.
       Although the model has  an option which allows the user to enter a daily intake of  lead
       from paint chips,  there is no guidance for estimating the amount of paint that might be
       ingested by a child.  The default assumption of the model is no paint chip ingestion.
       Because of the high concentration of lead in some older paint,  ingestion of tiny
       guantities of paint chips on a single occasion can cause serious lead intoxication and can
       cause greatly elevated  blood lead levels.  The EPA guidance for the IEUBK model states
       that the model is  not intended to address the situation where a child ingests a large
       guantity of lead in a single episode, though it can be used to evaluate exposure to
       household dust contaminated by fine paint particles.

Response:  The same points have already been made by EPA as part of the rationale for its
decision to exclude paint chip data from the guantitative evaluation of lead in the BHHRA and
instead to discuss the potential impact of paint chip ingestion in uncertainty sections of the
BHHRA report.  See  Section 5.4.4.1 of the BHHRA report and Technical Reply Document  (Revised
July 10, 1996),  page 17.   The IEUBK model addresses paint ingestion for the vast majority of
children  (probably more than 90%) who do not deliberately eat paint chips,  but inadvertently
ingest house dust containing paint particles.  Moreover, since the risk from yard soil
containing lead-contaminated mining waste is, by itself, enough to warrant soil remediation, any
additional lead intake from other sources such as paint would only increase the risk to the
children on the Site, and, thus, provide additional justification for soil cleanup.

32.    Comment:   The IEUBK model reguires a dust concentration and a percent of dust ingested
       that includes a paint source.  There is no guidance for estimating these inputs.  Also,
       the assumption used in  the IEUBK Model for the dust-to-soil ratio is based on empirical
       data from sites which include contribution of lead from paint and other sources.

Response:  The dust and percent of dust items appear on the Alternate Indoor Dust Entry screen
which falls under the Multiple Source Analysis option for dust in the IEUBK Model  (EPA 1994c).
The contribution of soil  to household dust is also an entry under the Multiple Source Analysis
option.  The Multiple Source option allows the user to use information about the contribution of
lead from other sources such as paint to household dust, but is not reguired to run the model.
The Multiple Source option was not used in the BHHRA for the Tar Creek Superfund Site.  Instead
concentrations actually observed in household dust on the Site were entered into the IEUBK
model.

33.    Comment:   Similarity between observed blood lead levels and community-wide blood lead
       levels predicted by the IEUBK model does not prove causation.  The model predictions are
       driven by assumed  exposures to soil; however, actual blood lead levels may be affected by
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       paint.   Failure to account for paint exposure in the model may result in under predicted
       blood lead levels.

Response:  The EPA does not disagree with any of these statements.  The IEUBK model was used in
the BHHRA to evaluate the potential health risks associated with environmental lead exposures at
residential properties, not to explain observed blood lead levels.  The IEUBK model predictions
indicated that elevated concentrations of lead in residential soil and dust could lead to
unacceptably high blood lead levels in children.  The model predictions did not account for
potential exposures to lead from ingestion of paint chips and would not be directly comparable
to the available blood lead data if paint chip ingestion is significant.  Nevertheless, the
model predictions are not inconsistent with the blood lead data generated by the Companies,
which indicates that community blood lead levels are actually higher than the model predictions.

34.    Comment:  Validation of the IEUBK model has misleadingly indicated that the model predicts
       well.  Cumulative freguency graphs appear to show a good match between predicted and
       observed blood lead levels.  However,  they do not compare the predicted and observed blood
       lead levels child by child, but rather by community as a whole.   When specific children
       are examined,  a low observed value often corresponds to a high predicted value and vice
       versa.   Also,  the model does not predict individual home or child risk reliably; it
       therefore should not be used for decision making for individual yards.

Response:  Prediction of the blood lead level in a specific child is not one of the intended
uses of the IEUBK Model; therefore, child by child comparisons of predicted and observed blood
lead levels should not be used to evaluate  model validity  (EPA 1994b).  The IEUBK model
estimates a geometric mean blood lead concentration for a hypothetical child based on a given
set of input values.   Lack of agreement between the predicted blood lead concentration and the
observed blood lead concentration for a specific child could be due to sources cf variability
that are not  accounted for in the calculation  (i.e., behavioral differences,  biological
differences, and measurement errors), and the use of model input values based on typical values
that may not accurately describe the specific child.

The model should not be expected to reproduce an observed blood lead level exactly.  The model
prediction interval about the mean is wide.  As long as the prediction interval includes the
observed blood lead level corresponding to the same exposure inputs, the model's performance is
considered satisfactory  (EPA 1994c).  Even when the predicted blood lead level seems unlikely to
include the observed blood lead level, there may be a plausible explanation.

Aggregation of children lessens the impact of deviation from central tendencies in measurement
and sampling errors and strengthens the observed relationship between environmental lead and
blood lead.  Demonstrations of concordance between model predictions and observed blood lead
levels at several communities with varying environmental lead levels indicate that the model
predictions are satisfactory, and that the model can be used for making decisions for individual
yards.

35.    Comment:  The  IEUBK model often systematically over predicts blood lead levels to a
       greater and greater degree as the soil lead level increases.

Response:  At very high soil lead levels, the IEUBK model might not adeguately account for
saturation effects that limit lead absorption.  Also, if the bioavailability factor used in the
model was higher than the actual bioavailability, the IEUBK model would over predict blood lead
levels for a site, and the effect would increase at higher soil concentrations.  However, that
does not appear to be the case at the Tar Creek Superfund Site.

36.    Comment:  The  geometric standard deviation (GSD)  of 1.6 used by the IEUBK Model (to
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       predict the blood lead distribution about the geometric mean)  may be too large.   If so,
       the predicted high end blood lead levels will be too high.   Using a modified method which
       increases sample sizes within cells,  EPA Region 8 has recently calculated smaller GSDS for
       Sandy and Bingham Creek,  Utah (1.4 and 1.43,  respectively).

Response:  The EPA has responded to a previous similar comment.   (See EPA Region 6, May 15,
1997:  Comment 15.)  The fact that a lower GSD was calculated at two sites using a modified
approach does not justify a change in the default GSD.  Evidence for the use of a lower GSD must
be weighed against evidence that suggests a higher GSD may be just as appropriate.  For example,
Chrostowski and Wheeler  (1992) report that GSD values obtained through community blood level
measurements average around 1.7.  And Chappell et al.  (1990) and Bornschein et al.  (1990)  report
GSD values of 1.63 and 1.69 for Leadville, CO and Midvale, UT, respectively.

37.    Comment:   GSDS calculated from empirical data may be overestimates due to exposure
       variations of children who visit yards where environmental  lead concentrations are
       different from their homes.   Since, remediation of soil reduces this source of exposure
       variation, post-remedial variation should be used to calculate the GSD and remedial
       levels.

Response:  Empirical evidence suggests that the removal of a single primary source of lead
exposure such as soil contamination may actually increase the GSD.  The EPA's Technical Review
Workgroup for Lead has calculated GSDS greater than 1.6 for groups of children with low lead
exposure.  When a single large source of lead exposure is removed, other lesser sources
contribute greater percentages  of the residual exposure and the greater variability in the
remaining sources actually increases the GSD.

38.    Comment:   The recommended individual GSD is similar to the  community-wide GSDS.   This
       implies that variation in  soil concentration throughout a  community explains little of
       the variation in a child's blood lead level.

Response:  The information provided in the comment is incorrect.  The GSDS were calculated to
estimate the interindividual variability of blood lead concentrations in children exposed to
similar environmental lead levels.   The sources of this variability include biological
variability, behavioral variability, and measurement errors.

39.    Comment:   The EPA's stated goal,  which is to have no more than 5% of children's blood lead
       levels be above 10 ug/dL, is arbitrary and not consistent with the Centers for Disease
       Control (CDC)(CDC, 1991).

Response:  The EPA's policy is to attempt to limit environmental lead levels so that a typical
child or group of children will have an estimated risk of no more  than 5% of exceeding the 10
ug/dL blood lead level.  That policy is not inconsistent with CDC  guidelines.  CDC has stated
(CDC, 1991) that primary prevention activities including community-wide environmental
interventions "should be directed at reducing children's blood lead levels at least to below 10
ug/dL."

40.    Comment:   The EPA should not use the lead concentrations measured in garden produce as
       inputs to the IEUBK model, since there is no apparent relationship with lead
       concentrations in soil at the Tar Creek Superfund Site.

Response:  In the BHHRA, homegrown produce concentrations were entered in the IEUBK model for
homes with gardens because produce consumption could contribute to the daily lead intake.   This
affected 27 out of 100 homes in the Study Group and 6 out of 15 homes in the Reference Area.
Produce ingestion raised the predicted blood lead concentrations at those homes by approximately
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0.2 to 0.3 ug/dL and, therefore,  also raised the percent probability of concentrations above 10
ug/dL (by varying amounts).  However,  the effect on the community aggregate estimates was very
small.  Inclusion of produce data had no significant effect on the conclusion of the risk
assessment.  Note that produce consumption was omitted from the calculations of preliminary
remediation goals.

41.    Comment:   Lead-based paint is  ignored as a source of lead exposure.   The condition of the
       lead-based paint was  not accounted for in comparing the Reference Area to the Site or in
       estimating risk.  The source of lead in soil is not clearly chat rather than paint.
       Lead-based paint is  widespread and in poor condition and is likely to be the most
       significant source of lead at  this Site.  Also, although the BHHRA indicated that nearly
       every exterior paint  sample contained large amounts of lead,  it disregarded paint as a
       source of lead exposure.

Response:  The EPA recognizes that deteriorated paint may have contributed to lead in soil and
dust at some homes,  affecting the measured concentrations of lead in soil and dust which were
used as inputs to the IEUBK model.  However, the evidence indicates that lead-based paint is not
the primary source of the elevated lead levels in soil and dust found at the majority of
residential properties in Picher.

Fewer than half of the exterior paint chip samples collected from the Study Group exceed the
5,000 milligrams per kilogram  (mg/kg) standard used by the U.S. Department of Housing and Urban
Development  (HUD) for lead in paint.   The available data indicate that the prevalence of lead
paint is no greater in the Study Group than in the Reference Area homes.  The EPA has discussed
these issues previously.  See Technical Reply Document  (Revised July 10, 1996):  second
paragraph on page 9 through second paragraph on page 11, and the section titled "Lead in Paint
as a Source" on pages 15 and 16.   It should be noted that, even if other sources of lead on the
Site pose a health risk, the risk from yard soil containing lead-contaminated mining waste is,
by itself, enough to warrant cleanup of that soil.

42.    Comment:   The very small number of houses sampled in the Reference Area is entirely
       inadeguate to make any meaningful comparison or conclusion regarding lead paint exposure
       at the Site.

Response:  For EPA's reply,  see Technical Reply Document  (Revised July 10,  1996), pages 9
through 10.  The EPA has acknowledged the limitations of the data, but the data that are
available provide no indication of any significant difference in the prevalence of concentration
of lead in paint chips found in the Study Group and Reference Area homes.

43.    Comment:   The recent  CHAMP blood lead and environmentallead data do not indicate that chat
       is the dominant cause of elevated blood lead levels in this community.   Of 45 children
       found to have blood lead levels greater than 9ug/dL,  nearly all had other sources of
       exposure such aspaint or home  lead hobbies.

Response:  The EPA cannot comment on these selected observations from the study without seeing
all of the data.  The BHHRA indicates that exposure to the elevated concentrations of lead in
soil and dust that are present at many Study Group homes could lead to unacceptably high blood
lead levels, and that the major source of elevated lead concentrations is mining waste.  The EPA
recognizes that there may be other sources of exposure.  However, the possibility of additional
exposures to lead from paint and other sources does not reduce the potential risks posed by
Site-related (i.e.,  mining-waste- related) soil contamination.  Moreover, since the risk from
yard soil containing lead-contaminated mining waste is, by itself, enough to warrant soil
remediation, any additional lead the risk to the children on the Site, and, thus, provide
additional justification for soil cleanup.
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44.    Comment:  The continuing nationwide downward trend in blood lead levels has been ignored
       in setting the remediation goal for lead in soil.

Response:  Even if the nationwide downward trend continues, it is likely that the rate of
decline in blood lead levels will decrease as general sources of lead exposure are eliminated.
Also, the trend locally may differ from the national trend, especially when there is a major
industrial source  (e.g., mining waste at the Site).

45.    Comment:  The amount of lead in indoor dust that was derived from outdoor soil is
       overestimated. The dust-to-soil ratio assumed at Tar Creek Superfund Site to calculate the
       cleanup level is likely biased upward by contributions from other sources to indoor dust
       lead,  therefore, the cleanup goal for soil is too low.  Also,  the Preliminary Remediation
       Goal (PRG)  document (EPA September 1996)  assumes that soil must be remediated to a level
       to account for a 200 ppm background level in house dust.  This "background" level is the
       upper limit of house dust levels in the Reference Area,  not an average as required for
       inputs to the IEUBK model.

Response:  Post-remediation indoor dust lead levels cannot be predicted with certainty because
they will be affected by other lead sources in addition to soil.  Moreover, as soil lead levels
drop, the relative lead contributions from other sources will likely increase, and the
relationship between soil lead and dust lead will probably weaken.  Therefore, any prediction
based on the current relationship of dust lead to soil lead is, at best, an approximation of the
relationship that will exist after remediation.

In the statistical approach presented in the PRG document, the current relationship between soil
lead and dust lead was not expressed as a ratio.  Rather, it was described by the regression
line from the comparison of the log of dust lead concentrations to the log of soil lead
concentrations for the Study Group homes, excluding four homes that had very high dust levels
apparently from sources other than outdoor soil.  The data were log-transformed for the
regression analysis because both soil and dust concentrations were found to be log normally
distributed.   This shows the best statistical estimate of the current relationship between lead
concentrations in soil and dust at most Study Group homes.  Based on this regression line and
IEUBK predictions, the PRG for lead in soil was determined to be about 500 mg/kg with an assumed
indoor dust lead concentration of approximately 160 mg/kg.

The estimated 160 mg/kg post-remediation level for dust does not seem unreasonably high when
compared to concentrations found in the Reference Area.  Excluding one extremely high outlier,
dust lead concentrations in the Reference Area ranged from 40 mg/kg to 221 mg/kg and averaged
114 mg/kg, approximately the same as the average lead concentration in the outside soil.  With a
soil remediation level of 500 mg/kg for the Study Area, there is no assurance that
post-remediation dust concentrations will drop much below the estimated 160 mg/kg level.

On the other hand it is possible that dust lead levels in some cases will not drop all the way
to the level predicted by the regression equation, due to other lead sources in the home.
Because of the uncertainty, the empirical approach was included in the PRG document to show the
effect that a higher dust lead concentration would have on the calculated PRG.  The 200 mg/kg
level was chosen as a reasonable upper bound estimate for dust lead in homes unaffected by soil
contamination or other lead sources.  Note that the resulting PRG (456 mg/kg) was not selected
by EPA in the Proposed Plan for residential areas at the Tar Creek Superfund Site.

46.    Comment:  Comparison of blood lead levels and risks between the mining area and the
       Reference Area are invalid unless both communities are similar in socioeconomic
       conditions, age and condition of houses,  education levels, and presence of lead paint and
       other sources.
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Response:  See Technical Reply Document (Revised July 10, 1996): section titled "Afton as a
Reference Site" on page 20.

47.    Comment:  The BHHRA failed to demonstrate that mining wastes are the source of elevated
       blood lead levels that may exist at Tar Creek Superfund Site residential areas.

Response:  The EPA has responded to this comment previously.  See Technical Reply Document
(Revised July 10, 1996):  Second paragraph on page 24.

48.    Comment:  Because other sources of exposure are not considered,  the cleanup level based on
       the risk assessment assumes that remediation of soil to this level will reduce children's
       blood lead levels to below the target goal.  In reality,  elevated blood lead levels will
       likely persist.  The IEUBK model ignores the contribution of lead paint, thereby over
       predicting the magnitude of the contribution from soil.  Conseguently,  lowering soil lead
       levels will not lower blood lead levels to the degree claimed by EPA.

Response:  The IEUBK model predictions showed that risks of  elevated blood lead levels from
exposures to elevated lead concentrations in soil and dust at the Tar Creek Superfund Site
exceed EPA's target, even without exposures from other major sources, and that reducing the soil
concentration to 500 mg/kg would reduce the risk to the target level.  The EPA expects that
overall long-term blood lead levels will drop following soil remediation; however, EPA has made
no claims with respect to declines in existing elevated blood lead levels.  A factor that may
slow actual declines in blood lead levels is the effect of the existing body burden of lead
resulting from previous exposures (see Response to Comment 24 above).  Also,  EPA recognizes that
lead paint may be a significant source of exposure at some homes, however, the evidence
indicates that paint is not the primary source of lead exposure at most homes in the Study Area.
Moreover, since the risk from yard soil containing lead-contaminated mining waste is, by itself,
enough to warrant soil remediation,  any additional lead intake from other sources such as paint
would only increase the risk to the children on the Site, and, thus, provide additional
justification for soil cleanup.

49.    Comment:  Most of the first draw tap water samples were actually flushed samples, because
       residents did not comply with the sampling protocol.  Four of the five highest water
       concentrations came from first draw samples,  presumably from the few residents who
       complied.

Response:  Under sampling protocol,  residents were asked not to run water from the tap for six
hours before the first draw samples were collected.  Although few residents complied fully with
this reguest, meaning that some water was drawn from the tap during the six-hour period prior to
sampling, it is not accurate to say that most of the first draw samples were actually flushed
samples.  A flushed sample is a sample which is collected after the tap was allowed to run for 2
or 3 minutes to replace all standing water in the pipe with fresh water.  In most cases where
residents failed to comply with the first draw protocol, the tap probably ran for a much briefer
period--30 seconds or less  (to fill a coffee pot, for example),  still leaving mostly standing
water in the pipe which would provide a valid sample.  Moreover, pre-sample draws (e.g., for the
coffee pot) might have occurred several hours prior to sampling.  In short, it is unlikely that
actual first draw concentrations would have been substantially higher than the concentrations
measured in the samples actually taken.  In any case, there is no basis for assuming that the
four highest samples measured represent the only residents who complied with the sampling
protocol.  Finally, higher lead concentrations in tap water can only mean that the risk to
children living on the Site is greater than predicted by the IEUBK model.  That is,  since the
risk from soil lead alone is enough to warrant remediation, any additional lead intake from
other media would only heighten the risk to the children.
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50.    Comment:   The risk assessment calculates the estimated probability of children exceeding
       the 10 ug/dL target level in the Study Group to be 21.6 percent,  using an assumption of
       one hypothetical child per home.  This assumption is unrealistic since one child per
       household would egual a total of 2,055 children in the Study Area,  which is far greater
       than the number of children who actually live there.

Response:  The 21.6 percent probability is an estimate of the community risk for the 100 homes
in the Picher Study Group and does not apply to the Study Area.

The 21.6 percent estimate is the aggregate of the risks for the 100 Study Group homes egually
weighted  (in other words, assuming one hypothetical child per home).  Community risk was
estimated in this way, despite the fact that many of the homes are not currently occupied by
small children,  because any residence could be occupied by children at some time in the future.
Community risk was also estimated as the aggregate risk of the children actually living in the
Study Group homes at the time of the study (37 children in  24 homes).   The result was similar,
19.1 percent.

51.    Comment:   The EPA's use of the IEUBK model to set a 500 ppm cleanup level for residential
       soil is contrary to EPA's own guidance on the use of the model.   The guidance manual (EPA
       1994c) states that use of the model to assess trigger levels for soil abatement at the
       community,  regional or state level "is discouraged because risks cannot be estimated
       adeguately."

Response:  This guote, taken out of context,  has been misinterpreted by the commenter.  Section
4.5.2.4 of the manual which is titled "Use of the Model to Assess Trigger Levels for Soil
Abatement at the Community, Regional, or State Level" states "Use of the present version of the
IEUBK model at this scale is discouraged, because risks cannot be estimated adeguately."  This
statement means that the use of input data at the community, regional,  or state level should not
be used, because model predictions based on mean exposure concentrations at that scale may
substantially underestimate risks from higher concentrations at some residences within the
larger area.  The model is intended to describe the exposure setting at a single residential
level, therefore,  input at the residence scale should be used.

Earlier statements in Section 4.5.2 make this meaning clear.  Referring to community or
neighborhood scale input, Section 4.5.2.1 states "We have little information on applications of
the IEUBK model with larger scale input data, and we must caution the user against using the
IEUBK model for this purpose."  Further on in Section 4.5.2.3 which is titled "Use of the Model
to Assess Risk of Elevated Blood Lead at the Regional or State Level," the manual states "There
is no empirical basis whatever for using the present version of the IEUBK model at this scale.
We have serious concerns that large scale input data may be totally inadeguate characterizations
of the spatially confined exposure for any individual child."

52.    Comment:   The use of the IEUBK model by EPA in connection with lead in soil sites is not
       discretionary.   Because EPA's reguirement that the model must be used to set cleanup
       levels constrains agency discretion,  and because the model is used at every site where
       lead in soil is a concern,  use of the model is subject to rulemaking reguirements,
       including the reguirements for public notice and comment.  Since EPA has never taken the
       model through rulemaking, its use in this manner is not legal.

Response:  This comment is incorrect.  The use of the IEUBK model by EPA for lead in soil sites
is discretionary and is not a reguirement.  Region 6 views the IEUBK model as a useful tool with
sound scientific basis and computational correctness.  Region 6 believes the IEUBK model is a
good predictor of potential long-term blood lead levels for children in a residential setting,
and that it can be used to support the establishment of remediation goals.
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When EPA Region 6 was deciding what method to use to estimate the risk that lead may pose to the
residential population at the Site, EPA Region 6 considered the following methods:  slope
studies, direct blood-lead measurements, and IEUBK modeling.  However, EPA Region 6 decided that
the IEUBK model was the best method for determining the risk posed by lead at the Site.

Slope studies are studies of empirical correlations between lead in environmental media and
blood lead.  A slope factor derived from a slope study is the relationship of the expected
increase in blood lead level to a certain increase in lead in an environmental media (e.g.,
soil).   Unlike the IEUBK model, slope studies are difficult to generalize to situations beyond
those where the data were specifically  collected.  Also, unlike the IEUBK model, "biological
and physical differences between sites and study populations cannot be incorporated explicitly
and quantitatively into regression slope factors from different studies"  (see Guidance Manual
for the Integrated Uptake Biokinetic Model for Lead in Children, OSWER Directive No. 9285.7-15-1
(February 1994) page 1-6).  That is slope studies do not explicitly include factors that
influence lead uptake and behavior in the body (e.g., ingestion rate, absorption through the
gut, etc.).  Slope studies lack the flexibility of the IEUBK model.  That is, slope studies are
limited in their ability to estimate the effects of alternate lead abatement methods with
different exposure pathways and different lead sources known to exist at the Site.

Direct blood lead measurements are primarily a "snapshot" of current risks, which may have been
influenced by health education activities at the Site, and are not a prediction of long-term
risk conditions.  For the Tar Creek Superfund Site risk evaluations, the IEUBK was considered
the best scientific approach for assessing lead risk for the BHHRA, for predicting potential
long-term blood lead levels for children, and for supporting the establishment of remediation
goals.

The remediation goal for lead in soil of 500 ppm was based not only on the IEUBK modeling, but
also on the findings of the BHHRA and Region 6 experience with other soil lead remediation
sites.

COMMENTS ON EPA'S EVALUATION OF REMEDIAL ALTERNATIVES

53.    Comment:  There appear to be an unduly large number of excavation related technologies
        (six of eight)  among the alternatives that were evaluated by EPA.  The FS provided little
       explanation of EPA's reasons for eliminating other technologies in the initial screening
       phase.   For example,  in situ lime treatment was eliminated with the explanation that the
       end product is a "solid nonleachable material considered impractical in residential
       areas."  Particularly because many researchers have investigated the use of lime and
       phosphate amendment technology and EPA has used it in other regions, some discussion and a
       detailed evaluation of this technology would be prudent.

Response:  Technologies for remediation of lead contaminated soil in residential yards that are
effective,  reliable, and acceptable to homeowners are limited.  Lead, being an element, cannot
be degraded like organic compounds, therefore, treatment technologies aim to alter the form of
lead to reduce its mobility and/or bioavailability.  Since young children, the segment of the
population most sensitive to lead's toxic effects, would potentially be exposed to the soil in a
residential setting, it is essential that the effectiveness of a soil treatment technology be
proven before it is used in such a critical application.  Existing treatment technologies for
reducing the bioavailability of lead in soil have not been proven to be effective in in situ
soil applications.  Furthermore, in situ soil treatment technologies are often impractical in
residential yard applications, because they often significantly alter the physical and chemical
properties of the soil making it unsuitable for residential topsoil.  Because requirements for
residential yard application are more stringent,  fewer technologies passed the initial screening
and the subsequent screening phase than might normally have been, the case under a less critical
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application.  Based on Superfund program precedents, excavation has been the most common remedy
selected to address soil in residential yards contaminated with lead which poses a health risk
to young children.

The alternatives evaluated in the FS provide a range of technologies that are appropriate and
practical for residential yard remediation applications.  With regard to in situ lime and
phosphate treatments, these technologies were screened out because they have not been shown to
be practical and suitable for a residential application.

Although other EPA regions are considering these technologies, Region 6 is not aware that lime
or phosphate treatment has actually been implemented at a Superfund site as a permanent remedy
in residential yards where young children would be directly exposed.  Region 7 reports that
phosphate treatment has not been proven effective at reducing lead bioavailability  (Region 7,
Oronogo Duenweg Mining Belt Site, Operable Units 2 and 3, Jasper County, Missouri, Record of
Decision, August 1, 1996).  And because of an unsuccessful attempt to use phosphate treatment at
a site in Bartlesville, Oklahoma (i.e., the National Zinc site), the State of Oklahoma does not
support phosphate treatment as a remedy for residential yards where young children would be
directly exposed.  The State's lack of support for phosphate treatment is a significant factor,
especially since the State must provide a cost match.  Until research is able to demonstrate
with assurance that lime or phosphate amendment technologies are effective in reducing
bioavailability in situ where young children are directly exposed in residential yards, removing
these technologies from further consideration in the initial screening phase is reasonable.

54.    Comment:   Alterative 4,  capping in place,  should have a similar degree of long-term
       effectiveness and permanence as the Preferred Alternative,  which is also essentially a cap
       in place remedy.  Also,  if EPA believes the yellow barrier tape will protect the integrity
       of the cap in the Preferred Alternative,  it should also protect the integrity of the cap
       in Alternative 4,  with minimal additional cost.

Response:  In Alternative 4, none of the contaminated yard soil is removed before placement of
the soil cap.  In Alternative 2, contaminated yard soil is removed to a maximum depth of 18
inches, which in most cases will remove all or most of the contaminated soil, before covering
with clean soil.  The soil barrier has a much more critical function under Alternative 4 than
under Alternative 2, because breaching of the soil cap represents a much greater potential
exposure risk from the remaining lead contamination.  The commenter apparently misunderstands
the purpose of the marker made of plastic material.  The comment refers to the material as a
yellow barrier tape, but it is a mesh fencing material  (a geotextile barrier may also be used).
The purpose of the plastic marker is simply to alert the resident or others of contamination
remaining at lower depths in the event of any future digging or construction, not to protect the
integrity of the soil barrier.   That is, the marker will line the bottom of excavated areas.
Whenever someone digs to that depth in the future, that person will be alerted by the barrier.

55.    Comment:   Fewer alternatives that mainly varied in the type of treatment technology should
       have been evaluated in detail.  Alternatives 5,  6, 7,  and 8 all involve treatment of
       excavated soil before final soil disposal.   Carrying all four of these treatment remedies
       through the detailed analysis of alternatives was inappropriate.   All but the least costly
       treatment alternatives should have been screened out early in the FS process.

Response:  CERCLA, the National Contingency Plan  (NCP)(40 CFR Part 300)  and EPA policy
encourages consideration of a variety and diversity of treatment technologies to address
hazardous substances at Superfund sites.  A different treatment technology is often the
distinctive feature that forms the basis for a separate alternative.  Properly evaluating
treatment alternatives as distinctly different as the ones associated with Alternatives 5
through 8 requires more than just a consideration of cost.  All the technologies considered by
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EPA had distinct differences and merited consideration in the detailed analysis of alternatives
phase.

56.    Comment:  More alternatives that incorporated CPMs should have been evaluated.

Response: CPMs were included in all the alternatives (see  Proposed Plan Section, "Common
Elements in All Alternatives") .   CPMs are complementary to EPA's efforts to remediate the lead
contaminated residential soil at the Site.  However, CPMs (education, house cleaning,  blood lead
monitoring, etc.) do not provide the type of permanent remedy at the Site which is contemplated
under the Comprehensive Environmental Response, Compensation, and Liability Act  (CERCLA) (see
e.g., CERCLA Section 121, 42 U.S.C. ° 9621).  Given the CERCLA preference for permanent
remedies, the inclusion of CPMs to the degree provided by Alternative 3 and as supplemental
components of the other alternatives(the no-action alternative excepted) was considered
appropriate.

57.    Comment:  The CHAMP is not mentioned in the RI/FS, or the Proposed Plan,  and CPMs are
       included generically only as  part of Alternative 3.

Response:  CPMs, which ate components of the CHAMP, were included as supplemental institutional
controls, which are common elements in all the alternatives, the no-action alternative excepted.
Alternative 3, included CPMs to a much greater degree.

58.    Comment:  The Companies'  CHAMP should have been specifically evaluated and incorporated
       into several different remedial alternatives as  part of the FS,  and carried through to the
       detailed analysis stage.

Response:  The remedy selection process normally evaluates remedy alternatives generically
(i.e., evaluates kinds of alternatives and technologies).  It is not necessary that special
names that identify the technologies or programs locally be used.  On the contrary, generis
identifications are preferable because they are understandable by a broader audience with
minimal explanation about local applications.  It is not necessary for the Companies'  CPM
program to be identified by name.  As a side note, the Companies's CHAMP is not a Sitewide
program, because its full services are not provided to some communities in the mining area,
Commerce, for example.  Limiting EPA's evaluation to the Companies' CHAMP would have potentially
restricted or limited the remedy.

59.    Comment:  The EPA indicated that if the CHAMP (the Community Health Action and Monitoring
       Program implemented by the Companies at the Site)  were shown to be successful in reducing
       children's blood lead levels,  it could be included as part of the remedy selected at the
       Site.  The EPA did not uphold its part of the bargain with respect to the CHAMP.

Response:  The EPA's Preferred Alternative does include CPMs as secondary components.   The
Companies' CHAMP, which is a CPM program, can be a complementary part of the remedy selected, as
it has been a complementary part of the removal action supplementing permanent response actions.
The EPA  encourages the Companies to continue the CHAMP as this could help satisfy the
reguirements in the remedy for supplemental CPMs.

The EPA disagrees with the commenter's statement that it has not followed through on any
commitments of promises it made to the Companies regarding their CHAMP.  The EPA has continually
stressed to the Companies that it encourages CPMs, including the CHAMP, as supplements and
complements to engineering controls.   The EPA has coordinated its Site response actions to
facilitate implementation of the CHAMP.  However, EPA has continued to express concerns about
the use of CPMs at the Site, including the CHAMP, as a substitute for permanent response
actions.
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60.    Comment:  At the very minimum,  a "no further action" alternative should have been
       developed and evaluated in the FS.   It would consist of essentially no further soil
       excavation beyond the 1500 ppm soil lead action level and the ongoing remediation,
       monitoring,  and education efforts being conducted as part of the CHAMP.

Response:  The EPA's no-action alternative (Alternative 1) is essentially a "no further action"
alternative.  In EPA's no-action alternative, the residential areas are left "as is" at the
completion of the removal action, without the implementation of remedial actions.  The NCP
expectation is that institutional controls (such as CPMs)  supplement engineering controls, not
that institutional controls be the dominant part of a remedy [see e.g.,40 CFR ° 300.430(a)].
The EPA's Alternatives 2 and 3 include CPMs.   CPMs play a bigger role in Alternative 3 than in
Alternative 2, but dominate in neither of these alternatives.

The EPA has made no commitments to the Companies to develop and evaluate a primarily CPM remedy.
The commenter's alternative  (described above in the comment) is not adeguately protective.  The
EPA has identified approximately 1600 residential properties with soil lead concentrations above
the health-risk-derived level of 500 ppm.  The lead contaminated soil at approximately 300 of
these properties is being addressed by the removal program.  The 1500 ppm action level, below
which no excavation takes place in the commenter's alternative, is 3 times EPA's
health-risk-derived level.  The commenter's alternative would potentially leave children in
approximately 1300 homes directly exposed to lead contaminated soil above safe levels.  The risk
associated with this level of potential exposure is considered excessive.  The level of
remaining risk posed by the commenter's alternative would place CPMs in the position of being
the major component of the remedy.  Also,  the source(s) at the houses of documented cases of
blood lead elevations would only be remediated after the source(s) are identified, which ignores
the fact that EPA has already determined that soil lead levels in excess of 500 ppm may pose a
health risk to children living there.  The commenter's alternative, like EPA's no-action
alternative, is not protective of human health, particularly children's health.

61.    Comment:  The Companies retained McCully,  Frick & Gilman, Inc.  (MFG)  to evaluate four
       remedial alternatives using the IEUBK model.  The four alternatives were:  (1)  FS
       Alternative 2,  consisting of excavation of residential soil (500 mg/kg Action Level), (2)
       FS Alternative 2 modified to include CPMs,  designated as Alternative 2a, (3) FS
       alternative 3,  consisting of excavation of residential soil (800 mg/kg Action Level)  and a
       CPM program, and (4)  a No Further Action Alternative, consisting of no excavation beyond
       EPA's interim removal action (1500  mg/kg Action Level)  and a continuation of existing
       CPMs.  MFG used more realistic assumptions about residual lead concentrations.   For
       example, for alternative 2, MFG used the average value calculated when homes above 500 ppm
       were excluded,  rather than a residual  lead concentration of 500 ppm.   MFG concluded that,
       following implementation of Alternative 3 or the No Further Action Alternative, the
       probability of a blood lead level exceeding 10  ug/dL would be significantly less than 5%.

Response:  MFG reached its conclusion, that Alternative 2 was overly conservative and the other
alternatives were adeguate,  by using community-wide average soil lead concentrations as inputs
to the IEUBK model to estimate community risks.  That approach is faulty for at least two
reasons.  First, community-wide average concentrations should not be used as model input values
to estimate community risks.  The IEUBK model guidance  (EPA 1994c) states "A common
misinterpretation of the IEUBK Model is that it predicts community geometric mean blood lead and
the fraction of children at risk when the input is the mean or geometric mean of household
specific environmental lead concentrations."   The guidance also states that such an approach
"may substantially underestimate the real risk from the most contaminated parts of the
neighborhood."  Furthermore, EPA's risk criterion is not intended to be applied on a community-
wide basis.  Generally, EPA's policy is to attempt to limit environmental lead exposures so that
a typical child or group of similarly exposed children will have an estimated risk of no more
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than 5% of exceeding the 10 ug/dL blood lead level.  Under the No Further Action Alternative,
approximately 1300 residential yards would be left with soil lead concentrations that exceed the
level at which children would have a greater than 5% chance of elevated blood lead levels.

The EPA's risk management decisions for remediation of residential lead contamination sites
focus typically on reducing the risk at the residence level.  Thus,  cleanup goals at the Site
are designed to reduce risk to a full time child resident receiving exposure at a residence to
no more than a 5% chance of exceeding a blood lead level of 10 ug/dL.

The second problem with MFG's analysis was the overly optimistic assumption of indoor dust lead
concentrations egual to zero for the alternatives that included CPMs (Alternative 2a,
Alternative 3, and the No Further Action Alternative).   In light of the uncertainties of the CPM
program in reducing dust concentrations over the long-term, such a nonconservative and
nonprotective assumption is not considered appropriate.  Even if dust lead levels could be
reduced to zero by "super cleaning," which is extremely doubtful, it is unlikely that they could
be maintained at that level without a complimentary soil remediation program.  MFG's report
admits that "the estimation of zero for the dust contribution may be overly optimistic" (Uphoff,
May 22, 1997, Attachment 4).  This unrealistic assumption results in underestimates of total
lead exposures.

62.    Comment:  MSG's experience at other sites suggests that the number of resident children
       with blood lead levels greater than 10 ug/dL may be zero under the No Further Action
       Alternative.

Response:  While such an outcome would be most welcome, it is highly unlikely given the high
percentages of children with elevated blood leads at the Tar Creek Superfund Site.  The data
from other sites cited by the commenter is inappropriately being applied to the Tar Creek
Superfund Site which has different circumstances.

63.    Comment:  MFG evaluated the four remedial alternatives described above by comparing the
       incremental reductions in risk to the incremental increases in costs,  environmental
       impacts and other short-term impacts.  MFG concluded that the incremental reductions in
       risk achieved by Alternative 2a over Alternative 3 or the No Further Action Alternative
       was far outweighed by the incremental increases  in cost and other impacts associated with
       Alternative 2a.  MFG reached the same conclusion when comparing Alternative 3 to the No
       Further Action Alternative.

Response:  The cost benefit analyses supplied by the commenter is invalid because the estimated
incremental risk reductions rely on a community-wide averaging approach which may have
substantially underestimated risk.  Further, as discussed in the Response to Comment 62 above,
the risk management goals typically apply at individual residences,  not to the community as a
whole.  Moreover, the short-term impacts to benefits analyses supplied by the commenter are
invalid because they rely on the same community-wide incremental risk estimates.

64.    Comment:  The volume of soil to be handled and the scope of the remedial activity
       increases by factor of approximately 18 for the  500 ppm action level for Alternative 2
       compared to the No Further Action Alternative and increases by a factor of 9 for the 800
       ppm action level for Alternative 3 compared to the No Further Action Alternative.

Response:  Neither the No Further Action Alternative nor Alternative 3 adeguately protect human
health for reasons discussed in above responses to other comments and in the ROD.  The increase
in soil volumes and the increase in the scopes of Alternatives 2 and 3 are proportional to the
increases in effectiveness of Alternatives 2 and 3.  The EPA's Preferred Alternative, an
excavation remedy which virtually eliminates residual risks, obviously removes and replaces much
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greater volumes of contaminated soil compared  to remedies that leave residual risk.

65.    Comment:  Based on the cost of a similar CPM program in Jasper County,  Missouri the cost
       of CPMs associated with Alternative 3 should be $100,000 per year rather than $300,000 per
       year as estimated in the FS.

Response:  The estimated annual CPM cost of $100,000 conflicts with other information provided
by the commenter.  The Jasper County CPM program cost according to a reference from the
Companies' consultant  (Uphoff, May 22, 1997, Attachment 3) is $67,000 annually plus staff time
from the Jasper County Health Department and the City of Joplin Health Department.  Also,
according to this reference, personnel for the CPMs consists of two full time eguivalents (FTE)
plus assistance in testing.  It's likely that cost for office space for the CPM personnel is not
included in the $67,000. This reference provided by the Companies' consultant also indicated
that the Jasper County program is "constrained" by the level of funding.  Therefore, a proper
program, unconstrained by funding such as the one envisioned in the FS, including the cost for
fully eguipped offices would certainly cost much more than the $100,000 estimated by the
commenter.  The estimated cost for CPMs in the FS is reasonable.

66.    Comment:  The EPA's Preferred Alternative is not cost effective.

Response:  CERCLA mandates that remedies be cost effective. Alternative 2, the Preferred
Alternative, is cost effective because its increased cost compared to the lower-cost
alternatives  (Alternative 3, Alternative 4, and the no- action alterative) is proportional to
its increased overall effectiveness compared to the overall effectiveness of the lower-cost
alternatives.

The increased cost of Alternative 2 compared to Alternative 3 is proportional to the overall
increased effectiveness of Alternative 2 compared to Alternative 3, because Alternative 2
addresses approximately 1312 residential properties with a permanent excavation remedy, which is
effective over the long-term; whereas, Alternative 3 addresses only approximately 619
residential properties with excavation and relies on CPMs, which for the Site lack long-term
effectiveness and permanence, to address the remaining residences.

The increased cost of Alternative 2 compared to Alternative 4 is proportional to the overall
increased effectiveness of Alternative 2 compared to Alternative 4, because Alternative 2
addresses the residences with excavation which is permanent rather than capping, which for the
residences at the Site lacks long-term effectiveness and permanence based on considerations of
the likelihood of cap disruption and the likelihood of significant drainage problems as
explained in the Proposed Plan in Section, "Long-term Effectiveness and Permanence."

Although, the no-action alternative is a no-cost alternative, it is not cost effective because
it does nothing to actually reduce the risks at the Site, and is ineffective overall in
protecting human health.

67.    Comment:  The Preferred Alternative (Alternative 2) does not address the risk of oral
       ingestion any more than less expensive and less time consuming Alternatives 3 and 4.   The
       EPA acknowledges that Alternatives 3 and 4 also have high technical implementability.

Response:  All the alternatives must be capable of satisfying the Remedial Action Objective
which is as follows:  Reduce ingestion by humans, especially young children, of surface soil in
residential areas contaminated  with lead at a concentration greater than or egual to 500 ppm.
Selection of a preferred alternative consists of evaluation of all of the nine criteria  [see 40
CFR ° 300.430(e) (9)] in accordance with the NCP, not just the criteria  (i.e.,  cost and
implementability) referred to in comment.  The EPA's evaluations of all nine criteria are
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included in the Proposed Plan (and in the ROD).   The following discussion highlights EPA's
evaluation of cost and implementability referenced in the comment.  Although Alternative 3 has
high technical implementability, it poses significant problems with regard to administrative
implementability and long-term effectiveness and permanence.  Alternative 4 has high
implementability, but is also lacking in long-term effectiveness and permanence.  Alternative 2,
EPA's Preferred Alternative, can be implemented without unacceptable short-term impacts to human
health or the environment, even though it requires an estimated six years to complete  (compared
to 3 years for Alternative 3 and 4) .   The EPA's Preferred Alternative provides for readily
implementable short-term measures to mitigate and control short-term impacts (e.g., spraying
excavation areas with water to control dust),  and thus allow the Preferred Alternative to be
protective during implementation.  Although Alternative 2 is more expensive, its increased
effectiveness over Alternative 3 and 4 is proportional to its increase in cost as explained in
response to Comment 66 (and in the Proposed Plan).

68.    Comment:   The EPA's evaluation of Alternative 3 does not adequately explain why this
       remedial alternative was  rejected,  especially in comparison to the Preferred Alternative
       (Alternative 2).

Response:  The EPA disagrees.  The EPA evaluated all the alternatives in accordance with the
requirements of 40 CFR ° 300.430 and documented its evaluation in the FS and the Proposed Plan.
Each alterative was evaluated against the nine NCP criteria.  Following this individual
analysis, a comparative analysis was conducted to evaluate the performance of each alternative
relative to the other alternatives, using the nine evaluation criteria.  This comparative
analysis identified the advantages and disadvantages of each alternative relative to the others
so that the key tradeoffs could be identified.  Alternative 2, the Preferred Alternative,
represented the best balance of trade offs among the alternatives in terms of the five primary
balancing criteria.  In selecting the Preferred Alternative, the modifying criteria of State
acceptance and community acceptance were also considered.  The Preferred Alternative was
properly evaluated in accordance with the requirements of 40 CFR ° 300.430, and the Preferred
Alternative best meets those requirements.  The EPA's evaluation was documented in the FS and
the Proposed Plan.

69.    Comment:   It is not clear why EPA considers an alternative with an 800 ppm action level
       and CPMs adequately protective for similar areas in the Region 7 portion of the Tri-State
       Mining District,  but not  for the Region 6 portion of the Tri-State Mining District.   The
       EPA's concern appears to  be related primarily to long-term effectiveness and
       implementability.

Response:  As the comment pointed out, Region 6's concerns with the 800 ppm action level are
primarily related to the  balancing criteria of long-term effectiveness and implementability.
Also, lack of state acceptance for CPMs, to the degree required for the 800 ppm action level,
was an important consideration.   A critical factor in implementability of CPMs is state
government and local government support, particularly from the local health departments.  State
and local governments in Region 7 have demonstrated more support and ability to fund and
implement CPMs for their portion of the Tri-State Mining District than the State and local
governments in the Region 6 portion of the Tri-State Mining District.  (See Response to Comment
87 below for additional discussion of this key factor.)  Region 6 is also concerned about
relying on institutional controls at the Site to address residual risk below 800 ppm.  That is
why Region 6 proposed a permanent engineering control  (i.e., excavation)  to address the residual
risk rather than an institutional control (e.g., CPMs).  Region 7 is also considering a
permanent engineering control (i.e.,  phosphate treatment) to address the residual risk and has
expressed some reservations about the long-term reliability of CPMs.

70.    Comment:   The EPA failed  to adequately consider the environmental impacts (impacts on the
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       borrow areas)  and other short-term impacts (such as truck traffic and industrial
       accidents)  of an extensive residential soil removal and replacement remedy (i.e.,  the
       Preferred Alternative).

Response:  The EPA disagrees.   Region 6 has considerable experience implementing residential
soil removal and replacement actions at other sites.  The EPA Region 6 has carried out such
actions without causing unacceptable short- term impacts to human health and the environment.
Removal actions at this Site,  which have been underway since 1995, and which are essentially the
same as the soil removal and replacement components of the Preferred Alternative, are also being
implemented without unacceptable short-term impacts to human health and the environment.   A
review of construction safety records from the start of the residential removal action in June
1996 to June 1997, shows no lost-time accidents or serious injuries, no injuries or illnesses to
workers from exposure to any contaminants, and no accidents or injuries involving the public.
Also, EPA' s implementation of the Preferred Alternative will include readily implementable
short-term measures  (e.g., dust control measures, traffic safety measures, personal protective
eguipment for workers, environmental protection measures, borrow area restoration and erosion
control measures,  measures to address health and safety of workers and the community, etc.)  to
mitigate and control short-term impacts and thus allow the Preferred Alternative to be
protective during implementation.

71.    Comment:  Alternative 4,  capping in place, unlike the excavation alternatives would not
       risk remobilization of  the lead.   This should be considered a benefit in terms of
       protection of human health and the environment.

Response:  Even though there is more potential for lead to be remobilized in an excavation
alternative, potential dust generation,  erosion, and other types of remobilization of lead are
readily controlled through measures to mitigate any potential short-term impacts.  For further
discussion about control measures for short-term impacts, see Response to Comment 70 above.

72.    Comment:  In Section 5.2.9 of the FS,  EPA appears to refer to relocation of certain
       residents in the area.   Is EPA considering relocation as part of the remedial action?

Response:  The EPA is not proposing to relocate residents as part of the remedial action. See
section, "Common Elements in All Alternatives" of the Proposed Plan for further explanation.
See also EPA's response to comments 19 And 20 in Part A of this Responsiveness Summary at
Section II(a).

73.    Comment:  With respect  to the Preferred Alternative,  there is no indication which
       residences, if any, would be given priority for performance of the remedial actions.
       Precedence should be given to residences with children exhibiting elevated blood lead
       levels.

Response:  Prioritization of cleanup actions is a detail that will be developed during the
remedial design.  However, residences of children with elevated blood lead levels will be given
the highest priority.

74.    Comment:  Why did the Proposed Plan fact sheet indicate that no Five Year Review is
       reguired?  Given that EPA is proposing a 30-year monitoring as part of the Preferred
       Alternative,  and given  historical experience with Operable Unit 1,  a Five Year Review
       would certainly appear  warranted.

Response:  The 30-year monitoring period is the estimated period for operation and maintenance
for cost estimating purposes.   Monitoring associated with the Preferred Alternative is primarily
related to the disposal area and not the remediated residential yards.  As the commenter
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recommended, based on experience with Operable Unit 1, a Five Year Review is warranted for parts
of Ottawa County where contamination remains at concentration levels which may pose a health
risk or an environmental risk.  A Five Year Review for areas addressed by Operable Unit 1 has
already been conducted and an additional Five Year Review is planned. However, for the
residential areas addressed in the ROD, where soil contamination above the health-risk- derived
level is removed, a Five Year Review is not necessary.

75.    Comment:  The EPA's use of the term "Indian owned lands" in the FS is confusing.

Response:  The term "Indian land" or the term "Indian owned land" means the categories of Indian
land as described in CERCLA ° 104(c)(3).  The terms "Indian land" and "Indian owned lands" are
used generically.

76.    Comment:  Why is wind erosion considered a potential transport mechanism of lead particles
       from chat piles for the initial contamination in the RI, but not a factor with respect to
       potential recontamination of the remediated yards in the FS?

Response:  During the active mining years, when earth-moving activity stirred up dust, the air
deposition of lead contaminated particles was likely greater than during the post-active mining
period.  Wind erosion is still considered a potential transport mechanism; however, the rate of
current air deposition with respect to recontaminating the remediated yards is small for most
properties.  For the other properties, the potential for recontamination will becontrolled by
appropriate dust and erosion control measures.

COMMENTS ON COMMUNITY PROTECTIVE MEASURES (CPM)

77.    Comment:  The EPA ignores its own guidance (EPA July 14, 1994), which states that
       development and promotion of public awareness programs focusing on the causes and
       prevention of lead poisoning in children should be considered in conjunction with other
       measures to reduce blood lead levels.

Response:  The comment is not correct.  The EPA has been encouraging and supporting public
awareness programs at the Site concerning lead poisoning and prevention.  The EPA's Preferred
Alternative includes health education which provides for public awareness programs focusing on
the causes and prevention of lead poisoning in conjunction with and supplemental to the active
response activities (e.g., engineering controls)  at the Site.

78.    Comment:  The sources of the observed elevated blood lead levels in Picher and Cardin do
       not appear to have been identified through an environmental assessment.  The EPA assumes
       that the source of the elevated blood levels is lead in soil.

Response:  From the context in which the comment was made it appears that the term
"environmental assessment" is referring to environmental sampling and behavioral assessments in
individual homes following the confirmation of blood lead poisoning of children living in those
homes.  While these "environmental follow-ups" are useful for managing cases of lead poisoning,
they are not necessary to determine sources of lead on a community-wide basis.  The EPA
conducted its own extensive community-wide environmental assessment.  The EPA investigations
indicated that the primary source contributing to elevated blood lead levels in children at the
Site is soil.

79.    Comment:  A CPM approach that directs that site assessments occur where elevated levels
       are identified, followed by remediating the identified sources(s), followed by monitoring
       is more comprehensive,  site specific and cost efficient, while being more protective of
       children's health than EPA's soil excavation approach at the Site.
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Response:  The EPA disagrees.  The approach described in the comment is not more comprehensive.
The EPA's investigations at the Tar Creek Superfund Site indicate that the primary source
contributing to elevated blood lead levels in children is soil.  In fact, the soil is so
contaminated that soil alone, without consideration of any other source of lead, poses an
unacceptable risk to children living on the Site.  Moreover, EPA's Preferred Alternative calls
for investigation of every home in the mining area to determine if the soil is contaminated with
lead above the health-risk- derived level.  In addition to comprehensive primary prevention,
EPA's Preferred Alternative includes supplemental CPMs such as health education and blood lead
monitoring.  The EPA works with and encourages the State and local governments and health
departments to continue blood lead monitoring.  The State and local health agencies normally
conduct follow-up environmental testing for cases of elevated blood lead levels to identify
sources, and these agencies normally conduct follow-up lead exposure reduction counseling.
Also, EPA does work with and encourage others, including the State and local governments and
health departments, to address the lead-based paint that may be contributing to elevated blood
lead levels in some homes.  The EPA's Preferred Alternative is cost-effective, because the
increase in effectiveness is proportional to the increase in cost (see Comment 66).

The approach described in the comment is a case management approach that deals with individual
cases and addresses sources of lead only after the children's blood lead levels have become
elevated.  It is unclear why the CPM approach discussed in the comment is described as being
"site specific."  In this context "site specific" appears to eguate individual cases or homes
with "sites."  If this is the meaning, then the approach described by the comment, does not
address all the "sites" or homes, but only the ones with cases of lead poisoning.  Site specific
in this context seems to be more of a deficiency than an advantage.   Because the approach
described in the comment does not include primary prevention on a community-wide basis, it is
considered less comprehensive than EPA's Preferred Alternative and less protective of children's
health.  The EPA's approach addresses lead contamination levels that may pose a risk wherever
these elevated concentrations are found in the residential areas.  The EPA hopes, in this way,
not only to reduce the risk to children who already have elevated blood lead, but to eliminate
dangerous poisons in the environment before they affect other children's health.

This comment highlights the differences between the approach that EPA uses to address lead at
Superfund sites and approaches used mainly by health departments.  The focus of health agencies,
with regard to lead is on addressing lead poisoning after it has occurred.  Under CERCLA, EPA's
main focus with regard to lead is to reduce environmental lead exposures that may pose a health
risk, whether or not lead poisoning has actually occurred.  This does not mean that EPA is not
concerned about individual cases of lead poisoning, nor does it mean that there is not some
overlap in responsibilities between EPA and health agencies.  The overall best approach is a
combined approach coordinating Superfund risk reduction activities,  focused on primary
prevention, with the health agency actions focused on managing cases of lead poisoning.

80.    Comment:   The CPMs described for Alternative 3 in the Proposed Plan do not include the
       following elements: institutional controls,  targeted health education and training,
       environmental assessments, abatement of identified sources,  and monitoring of the
       effectiveness of the CPM program.

Response:  In EPA's Proposed Plan the CPMs for Alternative 3 provided for all these elements
that the commenter indicates are missing.  However, the Proposed Plan listed only the major
elements of CPMs, and did not include many of the details specified by the commenter.  Such
details are usually specified during the design phase.  The specific details of the CPMs can
also be adjusted during implementation phase.  The EPA has no expectation that proposed plans
and RODs include all details of a remedial design.   Also, some of the CPM items proposed by the
commenter are items that would be provided for as part of lead poisoning and prevention programs
by others including health departments.
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81.    Comment:   The CPMs outlined in Alternative 3 should be broader.   Blood screening and
       sampling of lead sources should not focus on residences with residual risk from lead
       contaminated soil, but should include all residences where there are children under 6
       years of age.  Also CPMs should address sources other than soil  including paint,  water
       pipes,  hobbies, gasoline,  etc.  The communities can be badly misled if they believe soil
       removals addressed all sources causing elevated blood lead levels.   A purely soil-based
       abatement program gives communities a false sense of safety.

Response:  The EPA's investigations indicate that the primary source contributing to predicted
elevated blood lead levels in children at the Site is soil.  Therefore, focusing CPMs on
residual risk from lead in soil is appropriate.  This does not mean that other sources are not
of concern to EPA.  For example,  lead paint may contribute to lead exposures at some homes and
could be a major source of lead exposure at those homes; however, mining waste, and not paint,
accounts for most of the soil lead and lead in dust found at most homes.  The EPA does work with
and encourage others, including the State and local governments and health departments,  to
address the sources other than soil.  Community education efforts envisioned by the plan would
not be limited to education about soil and would caution that for some  homes other sources could
pose a health risk.

82.    Comment:   If Superfund created CPMs were the basis of a more comprehensive community
       attack on lead exposure, and this was understood, the preferences of the State and Tribes
       would change.

Response:  The State and Indian Tribes have been thoroughly involved and informed during the
remedy development process.  The State and Indian Tribes are familiar with the CHAMP CPM program
at the Site and are conducting some of their own CPM activities.  The State and Indian Tribes
are also familiar with EPA's soil removal activities at the Site.  It is speculation to presume
what the State and Indian Tribes may or may not prefer under certain circumstances.  The State
and Indian Tribes are informed and it is best to let them speak for themselves with regard to
their preferences.

83.    Comment:   A program focused just on yard cleanups is a short-term response which lacks
       permanency.  CFM5 have permanence.  Also, EPA has provided no support in the
       administrative record to substantiate its concerns that CPMs lack long-term effectiveness.
       There is considerable experience with CPMs at other Superfund sites which demonstrates
       that CPMs can be effective in the long-term.

Response:  The EPA disagrees.  Long-term effectiveness and permanence has specific meaning in
the NCP  (see 55 Fed. Reg. 8666, 8720, 8849, March 8, 1990).  An evaluation of permanence focuses
on the "magnitude of residual risk remaining" from hazardous substances remaining at the
conclusion of the remedial action.  This analysis includes  consideration of the degree of
threat posed by the hazardous substances remaining at the Site and the  adeguacy of controls used
to manage the hazardous substances remaining at the Site.  To the degree that remedies rely on
CPMs to address risk rather than engineering measures (e.g., removal of contaminated soil from
residential areas) concerns are raised about long-term effectiveness and permanence.  If a
primarily CPM remedy were used at the Site, significant residual risk would remain, as discussed
in the Proposed Plan.  CPMs, which are institutional controls, do not reduce the residual risk
at the Site and correspondingly,  raise concerns about long-term effectiveness and permanence.
On the other hand, the soil removal component of EPA's preferred alternative does reduce to
insignificant levels the residual risk to the population in the residential areas and,
therefore, has high long-term effectiveness and permanence.

That soil removal is a "short-term" response is not a negative attribute,  as the commenter seems
to imply, but a positive one—soil removal is rapid and therefore effective in the "short-term."
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That CPMs must be maintained in perpetuity is not a positive attribute, but a negative one.  The
comment seems to imply that a long-term program has permanency whereas a soil excavation remedy
that is completed in the short-term would not.  Permanency in the NCP has to do with how long
the remedy is effective and not how long it takes to complete it.  The EPA's Preferred
Alternative is directed at removing the source of the lead poisoning and is not focused mainly
on establishing a perpetual program to deal with the effects of lead in the environment.
Although in EPA's Preferred Alternative, some CPMs will supplement the soil removal, CPMs are
not the main focus.  The commenters acknowledged that "it is certainly too soon to be able to
demonstrate the permanence of any CPM created as part of a Superfund remedy ..."  (Uphoff,  May
22, 1997, Attachment 5) to which EPA agrees.

An evaluation of long-term effectiveness and permanence also includes an evaluation of the
"degree of certainty that the alternative will prove successful."  Evidence from other Superfund
sites regarding long-term effectiveness is mostly anecdotal.  As the reference (Uphoff, May 22,
1997, Attachment 5) supplied by the Companies' consultant confirms, most of these CPM programs
are relatively new having only been implemented in the early 1990's.  This limitation provides
little historical data upon which to evaluate long-term success.  There is little scientific
evidence to demonstrate that CPMs would be successful and reliable in the long-term.  The EPA is
unaware of published scientific studies that could be included in the administrative record on
the success and reliability of CPMs.  The lack of scientific evidence that CPMs would be
successful over the long-term is a significant concern to EPA for the Site.

Finally, under the NCP, EPA expects to use institutional controls such as CPMs as a supplement
to engineering controls, not as a sole remedy.  Under the NCP the use of institutional controls
shall not substitute for active response measures unless active response measures are determined
not to be practicable based on the balancing of trade-offs that is conducted during the
selection of the remedy.  See 40 CFR ° 300.430(a).  As described in the Proposed Plan and in the
ROD, the engineering controls (supplemented by CPMs) to be used under the Preferred Alternative
represent the best balance of trade-offs.  Moreover, EPA Region 6 experience with excavation of
lead- contaminated soil and backfilling of excavated areas has found it to be a successful
remedy.

84.    Comment:   If CPM were purely an educational program its results would unlikely achieve the
       Superfund intent (e.g.,  long-term effectiveness and permanence); but education with
       environmental assessment with intervention and monitoring is a different matter.

Response:  The comment alludes to one of the inherent weaknesses of CPMs, which is reliance on
education to affect  behavioral changes on a sustained basis to control exposures to lead
sources in the environment.  A reference provided by the Companies  (Uphoff, May 22, 1997,
Attachment 4) provided additional insights by acknowledging that the effectiveness of education
as a permanent solution is "not guantifiable due to lack of a study designed specifically to
test the effectiveness of educational intervention."  Rigorous statistical studies demonstrating
the benefits of education programs in preventing lead exposure are lacking.  The comment
attempts to allay concerns about the effectiveness of education in preventing lead poisoning by
suggesting that education with environmental assessment, intervention, and monitoring would be
effective.  However, such interventions would only occur after children developed elevated
levels of lead in their blood.   This approach does not prevent lead poisoning, but manages the
cases after they occur.

Over a period of years, every home will likely have children living in it.  Therefore, since
education alone is unlikely to be effective in preventing lead poisoning, it is likely that the
environment of every home with sources of lead above safe levels will potentially have to be
addressed.  When a major environmental source (e.g., yard soil)  has lead above safe levels, it
is more protective of health to abate the sources all at once up front rather than drag the
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process out over years by abating only when a child becomes lead poisoned.  Ultimately the soil
at every home will likely have to be abated anyway.

85.    Comment:   The EPA's concerns about the uncertainties regarding the administrative
       implementability of CPMs are somewhat doubtful in light of the fact that the very types of
       activities proposed as CPMs in Alternative 3 are those recommended by CDC [Centers for
       Disease Control]  guidelines to address elevated blood lead levels in the 10 ug/dL to 20
       ug/dL range in children age 6 and under.

Response:  The recommended responses based on blood lead ranges in the CDC guidelines in
guestion are for medical management  (i.e., health professionals conducting lead poisoning
follow-up activities).  They are not intended to guide environmental agencies that conduct
primary prevention activities like abating communitywide lead sources (for further discussion
see Technical Reply Document, Revised July 10, 1996, response #3 on pages 4 and 5).  The fact
that CDC recommends certain CPM-type actions does not mean that they are readily implementable,
only that they are recommended.  State and local government support, capability, and funding are
major factors that make CPMs more or less administratively implementable at a given site.  The
EPA's reasons for its concerns about the administrative implementability of CPMs at the Site
over the long-term are further discussed in Response to Comment 59 above.

86.    Comment:   The EPA has provided no support in the administrative record to substantiate its
       concerns  that CPMs are lacking in implementability.  In responding to EPA's concerns
       expressed in the Proposed Plan about the  uncertainty of a permanent CPM program at the
       Site in future generations, a commenter stated that "EPA has ignored the likelihood that
       the current generation will educate the future generation."

Response:  The EPA disagrees.  Lead is an inorganic element that does not dissipate or degrade
to an appreciable extent.  In the absence of an engineering solution that permanently removes,
detoxifies or isolates the lead, it will continue to pose unacceptable risks for many decades or
even centuries.   An expectation that an effective CPM program at the Site will be passed on from
generation to generation is unrealistic.

In order for CPMs to be effective for a long period of time several elements are reguired:

       •    A high degree of support and participation by state and local governments and the
            community;

       •    A permanent source of funding; and

       •    Participation by an organization willing and able to organize, administer and
            implement the program on a permanent basis.

These elements are lacking at the Tar Creek Superfund Site.

The community, local governments, and the State have supported the CHAMP program as a supplement
to primary remedial activities conducted by EPA, however, based on comments received on the
Proposed Plan, they do not support reliance on CPMs to a significantly greater degree than
proposed for Alternative 2.

Superfund generally cannot provide long-term funding for a permanent CPM program  (see e.g., 40
CFR ° 300.435).   Based on the lack of support for a significantly increased role for CPMs at the
Site, the State and local governments are unlikely to provide the funding.  The Companies have
funded the existing CHAMP program but have not offered a permanent or long-term funding
commitment.  Moreover, even if a source of long-term funding could be found for a permanent CPM
-------
program, as explained in our response to comments 56 and 84,  CPMs do not provide the type of
permanent remedy at the Site which is contemplated under the Comprehensive Environmental
Response, Compensation, and Liability Act (CERCLA)  (see, e.g.,  CERCLA Section 121,  42 U.S.C. °
9621).

The existing CHAMP program was implemented by the University of Oklahoma Health Sciences Center
with funding from the Companies.  The existing CHAMP program has been well received; however,
the University of Oklahoma is primarily an educational institution and would not normally be
expected to organize and operate a major long-term health education and monitoring program of
the type that would be reguired.  When the Indian Health Service, The Oklahoma Department of
Health, and the Ottawa County Health Department,  organizations  that might be able to undertake
such a long-term program,  were approached by the Companies to implement the CHAMP program,  none
were able to do so because of various limitations of their programs.

Based on these considerations, EPA is justified in its concerns about the permanence and
long-term effectiveness of a CPM program to the degree reguired for Alternative 3 at the Tar
Creek Superfund Site.

87.    Comment:  Recommendations by the National  Remedy Review  Board (NRRB)  regarding CPMs  and
       inclusion of CPMs by Region 6 as part of the Preferred Alternative are clear endorsements
       of the efficacy, effectiveness and implementability of CPMs.

Response:  With regard to the Tar Creek Superfund Site, the NRRB recommendations stated that
CPMs are "likely to play an important supplemental role."  The  EPA still has concerns about the
long-term "efficacy, effectiveness and implementability" of CPMs for the Site if relied on to a
significantly greater degree than envisioned in the Preferred Alternative.  The Companies are
encouraged to continue the CHAMP to supplement the engineering  controls planned for the Site.
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                       Attachment I to Section II, Part B of the Responsiveness Summary

                                           TAR CREEK SUPERFUND SITE
                                    DETAIIiED RESPONSE TO COMMENTS RECEIVED
                                         DURING PUBLIC COMMENT PERIOD
                                        FOR THE REMOVAL ACTION FOR THE
                                               RESIDENTIAL AREAS

                                                 May 15, 1997

INTRODUCTION

       The U.  S. Environmental Protection Agency  (EPA)  memorialized the selection of the response
action for the removal in question in an action memorandum dated March 21, 1996.  Pursuant to 40
CFR ° 300.820(b)(2), in a letter of March 6, 1997, EPA responded to comments submitted during
the public comment period regarding the residential removal action at the Tar Creek Superfund
site  (the "Site").  The EPA's March 6, 1997, letter addressed comments received from the
following:  Leslie C. Nellermoe on behalf of ASARCO Inc. in a letter of August 16, 1996; Gary D.
Uphoff on behalf of ASARCO Inc., Blue Tee Corporation,  Childress Royalty Company, Inc., Gold
Fields Mining Corporation, and The Doe Run Resources Corporation in letters of October 21, 1996
and October 22, 1996; and Lisa G. Esayian on behalf of NL Industries, Inc. in a letter of
October 21, 1996.  ASARCO Inc., Blue Tee Corporation, /Royalty Company, Inc., Gold Fields Mining
Corporation, NL Industries, Inc., and The Doe Run Resources Corporation are referred to
collectively in this document as the "Companies."  This letter also addressed the comments of
Edward B. Cohen of the U.S. Department of the Interior  (DOI) which he submitted, in a letter of
October 21, 1996.

       As explained in EPA's March 6,  1997,  letter,  the comments submitted by the Companies and
DOI during the public comment period had already been answered once by EPA, or else they did not
provide information which warranted any action, accordingly, EPA did not believe that the
comments were significant.  Therefore, EPA did not need to reply to the comments submitted
during the public comment period as part of the administrative record for the removal action
called for in the March 21, 1996, action memorandum  [see 40 CFR ° 300.820(b) (2)].  Nevertheless,
because there is public interest in the issues raised in the comments submitted by the Companies
and DOI during the public comment period, EPA decided to provide this detailed response to those
comments, and to include this detailed response in the administrative record for the remedial
action for the residential areas on the Site.

       The documents that EPA relied upon in preparing this detailed response to comments or
other documents referenced in the text of this response include the following:

Agency for Toxic Substances and Disease Registry  (ATSDR), February 1995, Lead and Cadmium,
Exposure Study for the Jasper County,  Missouri Superfund Site

Bornschein, R.L., Clark, C.S.,Grote, J., Peace, B.,  Roda, S., and Succop, P., 1988, Soil
Lead-Blood Lead Relationship in a Former Lead Mining Town.  In Environmental Geohemistry and
Health Monograph Series 4.  Lead Soil:  Issues and Guidelines. (B.E. Davies and E.G. Wixsons,
Eds.),pp. 149-160, Science Reviews Limited,  Northwood,  England.

Bornschwin, R.L., Clark, C.S., Pan, U.W.,et al 1990, Midvale Community Lead Study, Department of
Environmental Health, University of Cincinnati Medical Center.

Burkart, Burke, July 6,1995,Report of Analysis of Tar Creek Soil Samples for Ecology and
Environment Inc.
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Burkart, Burke, September 23,1995,Report of Analysis of Tar Creek Soil Samples for  Ecology and
Environment Inc.

Casteel, S.W.,Weis, C.P., Henningsen, G.M., Hoffman,E.,Brattin, W.J.,Hammon T.L., May 1996,
Bioavailability of Lead in Soil Samples from the Jasper County, Missouri Superfund Site,
Document Control Number 04800-030-0161

Centers for Disease Control(CDC),1986a,Kellogg Revisited - 1983.  Childhood Blood Lead and
Environmental Status Report,  Panhandle District Health Department and Idaho Deparment of Health
and Welfare, Center for Environmental Health, Centers for Disease Control, U.S. Environmental
Protection Agency.

Centers for Disease Control,  1986b, East Helena, Montana, Child Lead Study, Lewis and  Clark
County Health Department and Montana Department of Health and Environmental Science, Centers for
Disease Control, Public Health Service, U.S. Department of Public Health and Human Services,
Atlanta, Georgia.

Centers for Disease Control,  October 1991, Preventing Lead Poisoning in Young Children

Chappell,W.,et al.,1990, Leadville Metals Exposure Study, Colorado Department of Health(Division
of Disease Control and Environmental Epidemology), University of Colorado at Denver(Center for
Environmental Sciences), and U.S.  Department of Health and Human Services(ATSDR/PHS).

Community Health Action and Monitoring Program(CHAMP)Quarterly Report, July 1996 - October 1996,
University of Oklahoma, Health Services Center

Dames & Moore, November 2, 1994, Residential Yard Assessment Report for Jasper County, Missouri
and Cherokee County, Kansas

Drexler, John W., June 24, 1996, Laboratory for Environmental and Geological Studies, Department
of Geological Studies, University of Colorado, Bolder, Colorado, Laboratory Report of Lead
Speciation for Bureau of Land Management

EPA, April 1992, Guidance for Data Useability in Risk Assessment  (Part A), Final

EPA, July 14,1994, Revised Interim Soil Lead Guidance for CERCLA Sites and RCRA Corrective
Action Facilities, OSWER Directive No. 9355.4-12

EPA, February 1994, Guidance Manual for the Integrated Exposure Uptake Biokinetic Model for Lead
in Children, OERR Publication No.  9285.7-15-1

EPA, 1995, Evaluation of the Risk from Lead and Arsenic, Sandy Smelter Site Sandy, Utah, Draft
Final, July 1995.

EPA, Region 6, Technical Reply Document, Residential Area Response Actions, Tar Creek Superfund
Site, (Revised July 10, 1996)  .  Note:  This referenced document can be found in the
Administrative Record File which is located at the repositories including the Miami Public
Library in Miami, Oklahoma.

EPA, Region 6, August 1996, Baseline Human Health Risk Assessment Report, Tar  Creek Superfund
Site, Ottawa County, Oklahoma, Prepared for EPA by Ecology and Environment, Inc.

EPA, 1989, Risk Assessment Guidance for Superfund:  Volume 1 - Human Health Evaluation
Manual,(Part A),Interim Final
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EPA, Region 6, May 5, 1995, Supplemental Region 6 Risk Assessment Guidance Draft

Oklahoma State Department of Health(OSDH),1995, Ottawa County Blood Lead Summary, Memorandum:
To:  Jennifer Lyke (ATSDR), From Kim Quinn (OSDH). December 18, 1995.

U.S. Department of Housing and Urban Development(HUD),  1995.  Guidelines for the Evaluation and
Control of Lead-Based Paint Hazards in Housing

In responding to comments by the Companies and DOI, the following terms are used as indicated
below:

       •    Study Area - means the mining area of Ottawa County which was the subject of the
            Baseline Human Health Risk Assessment(BHHRA);

       •    Study Group - means the 100 homes in Picher where multi-media environmental samples
            were taken;

       •    Reference Area - means the 15 homes in Afton, Oklahoma which are outside of the
            mining area where multi-media environmental samples were taken, these homes were used
            for comparison to homes within the mining area;

            OSDH survey - means the Oklahoma State Department of Health(OSDH)Picher blood lead
            survey unless the OSDH county-wide survey is specifically referenced.

EPA'S RESPONSE TO COMMENTS

1.     A commenter stated that the median blood lead level of 3.8 ug/dL for children at the Tar
       Creek area,  relative to the soil lead levels,  is low.  The comment was based on the
       Oklahoma State Department of Health (OSDH)  blood lead survey conducted in Ottawa County in
       1995,  for the children ages 1-5 years old.   This commenter also stated that the incidences
       of elevated blood lead levels are probably more  influenced by socio-economic, conditions
       and the presence of deteriorating lead paint than by lead in soil from chat.

Response:  The median blood lead level of 3.8 ug/dL cited in the comment is based on the
county-wide results from the OSDH 1995 blood lead survey.  That value is not representative of
blood lead levels in the mining area, which encompasses only a part of Ottawa County.  Over
one-third of the 232 children tested county-wide were residents of communities outside of the
mining area.   The OSDH survey results showed that blood lead levels of young children in the
city of Picher, which is near the center of mining activities in the county, were substantially
greater than in other communities and the county as a whole.  The proportion of young children
ages 1-6 years old found to have blood lead levels of 10 ug/dL or greater in Picher was 21%  (10
out of 48) versus 4%(4 out of 105) in the rest of Ottawa County.

The results of EPA's 1995 investigation indicate that mining waste is the major source of
elevated lead levels in soil and dust within the mining area, and therefore an important
contributor to lead exposure.  Lead concentrations in soil from the Picher Study Group homes
exhibit highly significant correlations with the concentrations of cadmium  and zinc, which
along with lead are the elements primarily associated with area mining wastes.  The correlation
between soil and dust lead concentrations in the Study Group homes is also highly significant,
with lead concentrations in soil accounting for 67% of the variability of lead concentrations in
house dust.  While lead paint may be present at some residences and a possible contributor to
the lead concentrations in soil and dust at those residences, it cannot account for the major
differences in soil and dust lead concentrations between the Study Area and the Reference Area.
The available paint chip data show no significant difference in the prevalence of lead-based
-------
paint between the Study Group and Reference Area homes.

2.     A commenter noted that higher blood lead levels have been correlated with lower
       socio-economic conditions in a nationwide study and have been found higher in older
       cities.   The commenter stated that some elevated blood lead levels would therefore be
       expected at the Site,  regardless of past mining sources, due to lead from other sources.

Response:  The commenter provided no evidence that socio-economic conditions are a significant
factor affecting lead exposure or blood lead levels at the Site, especially in comparison with
the prevalence of mining waste at the Site.  The commenter does not explain why similarly aged
communities near the historical mining area have significantly lower percentages of elevated
blood lead levels compared to, for example, the community of Picher.

3.     A commenter stated that the EPA lead model version 0.99 may highly overestimate the actual
       blood lead levels.

Response:  The Integrated Exposure Uptake Blokinetic  (IEUBK) Model for Lead in Children  (EPA,
February 1994)  could overestimate actual blood lead levels for a population if the population's
actual exposures were less than that estimated from the exposure input assumptions and/or if the
actual bioavailability of lead in environmental media at the site was less than the value used
in the model.  However, this has not been demonstrated at the Tar Creek Superfund site.

4.     A commenter stated data from residential areas near some mining sites show little
       relationship between observed blood lead and soil lead concentrations,  and that this is in
       contrast to the IEUBK model which predicts a direct relationship between soil and blood
       lead levels.  The commenter also stated that EPA recognizes that dust and paint are
       possible major contributors to elevated blood lead levels in children,  and that any
       strategy to reduce lead risk at a site needs to consider not only soil,  but these other
       possible major sources.

Response:  Reliable blood lead data are difficult to obtain, and the interpretation of the
results is also often difficult because of confounding factors such as small sample sizes.
Also, for a given site, soil may not be the main source contributing to increases in blood lead
level.  Even if there is a significant source of lead in the soil, if it is relatively
nonbioavailable, then soil lead may not be a significant contributor, which is not the case for
the Tar Creek Superfund site.  The OSDH report of the results of the Ottawa County blood lead
survey provided no information about the known or likely sources of lead exposure for the
individuals who exhibited elevated blood lead levels.  Lead-based paint is certainly one
possible source.  However, the relatively greater number of young children found to have
elevated blood lead levels in Picher versus other parts of Ottawa County strongly suggests that
there is a connection with mining-related contamination.  Moreover, EPA studies have found that
the mining waste lead found in the Tri-State Mining District is highly bioavailable.  The EPA
recognizes that site remediation should consider all significant sources of potential lead
exposures; nonetheless, EPA's Baseline Human Health Risk Assessment  (BHHRA) Report  (EPA, August
1996) shows that the risk to  human health from Site soil lead alone, without even considering
other sources of lead  (such as lead-based paint), is such that it poses an unacceptable threat
to human health(especially the health of children).

5.     A commenter noted that declines in blood lead levels have been observed in smelting and
       mining towns that mirror national declines associated with the decrease in lead sources
       such as leaded gasoline,  house paint,  lead soldered cans, and stricter controls on
       emission sources or closure of smelters.

Response:  Leaded gasoline, lead-based paint, lead soldered cans, etc. historically have been
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significant general sources of elevated blood lead levels.  Lead exposure from these sources
would have been superimposed upon any location-specific exposure - from mining and smelting
wastes, for example.  As these general sources have been reduced or eliminated,  blood lead
levels have declined throughout the population.  Therefore, it is not surprising that blood lead
levels in mining and smelter areas also have declined as part of the national trend.  However,
mining and smelting wastes alone can be a significant source of lead exposure, and blood lead
levels in mining and smelting areas may still be higher than in similar areas without mining and
smelting activities, despite the general decline in other sources of lead exposure.  Also, the
comment is a generalization.  Blood lead levels can vary significantly from town to town.  The
EPA gathered site-specific data and analyzed it based on Site conditions.  As documented in the
BHHRA Report, the soil lead on the Site poses a significant human health risk—especially to
children.  Also, blood lead levels for specific towns may be different from the national trends,
especially with regard to the magnitude of declines.

6.     A commenter stated that EPA's OSWER lead directive (EPA,  July 14,  1994) recognizes that
       remediating soil may provide limited risk reduction if other significant sources
       (e.g.,lead-based paint or contaminated drinking water)  are present.

Response:  The EPA acknowledges that lead-based paint could be a major source of lead exposure
at some homes, though lead-based paint does not appear to account for most of the lead
contamination in soil and dust at the Site.  It is much less likely that contaminated drinking
water is a significant source at homes at the Site based on EPA sampling.  The EPA recognizes
that site remediation should consider all significant sources of potential lead exposures.
Nonetheless,  the BHHRA Report shows that the risk to human health from Site soil lead alone,
without even considering other sources of lead  (such as lead- based paint),  is such that it
poses an unacceptable threat to human health (especially the health of children).

7.     A commenter stated that CDC believes the major source of lead in children nationwide is
       from paint applied to homes beforee 1978 (HUD,  1995).

Response:  While from a nationwide perspective, lead paint applied to homes before 1978 is
considered the major source according to the comment,  from a site-specific perspective, other
sources(e.g., smelters, mining, etc.)of lead can dominate.  Such is the case for the Tar Creek
Superfund site where EPA's studies indicate that mining waste is the major source.

8.     A commenter noted that EPA guidance recommends  that site-specific information should be
       used in the MLJBK model whenever possible so that the risk more accurately characterizes
       the site.

Response:  A considerable amount of site-specific data, including lead concentrations in soil,
house dust, and tapwater at individual residences, were collected for the BHHRA and  were used
in the IEUBK model.  Model default values for exposure parameters were used in the absence of
site-specific values.

9.     A commenter stated that scientific data from other sites with metals  in soil indicate that
       actual exposures at the Tar Creek Superfund site would be less than default exposure
       assumptions in the IEUBK model.

Response:  There can be significant variation between lead exposure conditions and forms of lead
from site to site that effect actual exposures.  The commenter supplied no specific information
indicating that the scientific data from another metal-contaminated site were comparable to data
collected at the Tar Creek Superfund site with regard to the important specific parameters
influencing blood lead levels.  In short, there was no indication that these data would be
applicable to the Tar Creek Superfund site.
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10.    A commenter stated that indoor dust-to-soil ratios have been found to be lower than the
       IEUBK model default at sites with no active or recently active lead emission sources or
       limited outdoor areas with elevated lead in soil.   The commenter stated that a study at
       the Tacoma smelter, Tacoma,  Washington,  during smelter operations and shortly after
       closure,  found that the indoor dust was  more related to airborne dust from smelter
       emissions than to soil from the yard.

Response:  The commenter supplied no specific information that the conditions at the Tacoma
smelter or the other sites referenced were similar to the conditions at the Tar Creek Superfund
site.  That is,  there was no indication in the  comment,  that indicated that the scientific data
from the Tacoma smelter site or other sites referenced would be specifically applicable to the
Tar Creek Superfund site.  Also, with regard to the indoor dust-to-soil ratio at the Site, the
indoor dust-to-soil ratio is one of the input variables entered under the multiple source option
of the IEUBK model.  This option is intended to be used when household dust data have not been
collected.  However, the multiple source option was not used in the BHHRA because household dust
data were available for the Study Group and Reference Area homes.

11.    A commenter stated that lead ingestion rates from dietary sources have been reevaluated
       and that  lead levels in food continue to drop in correspondence to lead removal from food
       cans and  lead in gasoline.

Response:  The comment seems to be suggesting that the IEUBK model default assumptions for
dietary lead may be an overestimate, given more recent studies that show lead levels in food are
dropping.  However, the comment provided no specific supporting information.  According to the
guidance manual  for the IEUBK model  (EPA, February 1994), "Because two major sources of lead in
food (lead-soldered cans and air deposition on  food crops) have been greatly reduced or
eliminated, dietary lead is believed to be relatively constant since 1990, especially for
children less than seven years."  Using the current IEUBK model default assumptions for dietary
lead intake, food already accounts for only a small portion of the total estimated lead uptake
in the Tar Creek Superfund site Study Group.   Therefore,  small reductions in the dietary input
values would likely have a small effect on the  modeled blood lead predictions.

12.    A commenter suggested that factors such  as chemical form mineralogy,  and particle size can
       reduce the absorption of lead through the gastrointestinal  tract.

Response:  The commenter presented no site-specific information on how these factors have
affected bioavailability of lead in soil at the Tar Creek Superfund site.  Findings from
research conducted by EPA Region 8(Casteel et al., 1996)indicate that lead in yard soil and
milling waste samples taken from the Tri-State  Mining, District has a bioavailability of  30% or
possibly higher.

13.    A commenter seemed to suggest that children's exposure to lead will be reduced because
       large chat particles will not adhere to  their skin.

Response:  At the Tar Creek Superfund site, high concentrations of lead and other metals from
mining waste were found throughout the Site in  fine soil particles which are more likely to
adhere to skin and to be ingested by children than larger particles.  The exposure and risk
estimates for the Site were based on the concentrations of lead and other contaminants actually
measured in the  fine soil fraction that passed  through a 60-mesh sieve.

14.    A commenter stated that several recent studies of lead in soil at mining and smelter sites
       report lower than 30% absorption.
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Response:  There can be significant site-to-site variablity in bioavailability and adsorption of
lead due to the various forms of lead that may be present at any given site.  The commenter
supplied no specific information indicating that the forms of lead identified in the studies
referenced were comparable to the forms of lead identified at the Site with regard to important
parameters influencing blood lead levels.  In short, there was no indication that the data were
applicable to the Tar Creek Superfund site.  While it is true that some forms of lead found at
mining sites have bioavailabilities significantly lower than the IEUBK model's 30% default value
for oral absorption, evidence suggests that the bioavailability of lead in soil in the Tri-State
Mining District is not less than 30%.  The EPA Region VIII's recent study of bioavailability of
lead in soil samples from the Jasper County,  Missouri Superfund Site  (Casteel et al.,1996)
reported absolute bioavailabilities for lead in the range of approximately 30% to 40%.

15.     A commenter suggested that the IEUBK model default value of the geometric standard
       deviation(GSD)that was used for the Tar Creek Superfund site was too high.   (Note:  GSD is
       an expression of the variability of a set of data,  in this case blood lead data.)

Response:  There are no paired blood lead and soil and/or house dust lead data available for the
Tar Creek Superfund site Study Area that would allow a site specific GSD to be calculated.  Site
specific blood lead GSDs, adjusted for all known lead exposure factors, have been calculated for
at least six smelter and mining sites:

              Kellogg,  ID,  1983(CDC 1986a),GSD = 1.60;
              East Helena,  MT,  1983(CDC 1986b),GSD = 1.53;
              Leadville,  CO,  1987(Chappell et al.,1990),GSD = 1.63;
              Telluride,  CO,  1986(Bornschein  et al.,1988),GSD = 1.49;
              Midvale,  UT,  1990(Bornschein at al.,1990),GSD = 1.62;  and
              Sandy Creek,  UT,  1995,(EPA 1995),GSD = 1.4

The adjusted GSDs for these sites range from 1.4 to 1.63 and average 1.55.  While the activity
patterns and potential lead exposure pathways for children living at these sites may be similar,
which would lead to the assumption that the interindividual variability in blood lead levels, as
measured by the GSD, should be similar, the empirical data indicate that there is still some
variability in the GSD between sites.  The site specific GSD of 1.4, calculated for Sandy Creek,
falls at the low end of the range of GSDs for the six sites, three of the sites had GSDs, of 1.6
or higher.  There does not appear to be any reason to believe that the GSD for Sandy Creek,
which is primarily a smelter site, would be any more appropriate for the Tar Creek Superfund
site, primarily a mine tailings site, than the site specific GSDs for any of the other sites.
Since the data needed to calculate a site specific GSD for the Tar Creek Superfund site were not
available, the decision was made to use the default GSD of 1.6 recommended in the IEUBK model
user's guide rather than to arbitrarily adopt a GSD from some other site that might or might not
be a better value for the Tar Creek Superfund site.

16.     A commenter pointed out aspects of Community Protection Measures (CPM)(e.g.,  education,
       house cleaning with high efficiency particulate vacuum cleaners (  HEPA VAC,  etc.)  that the
       commenter suggests have advantages over more conventional soil removal approaches.  The
       commenter noted specific examples where CPMs have resulted in significant reductions in
       blood lead levels apart from soil removal.

Response:  The EPA recognizes that in the short term CPMs,  especially the education and
intervention portions of these program, can play a supplementary role at reducing lead risk to
children at the Site.

17.     A commenter noted that EPA guidance recommends and allows for addressing lead sources
       other than soil as feasible.
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Response:  The EPA supports efforts to address other possible sources of lead exposure at the
Site as feasible.  However, at the Tar Creek Superfund site, EPA studies indicate that, in most
cases, the elevated blood lead levels predicted by the IEUBK model are due primarily to elevated
concentrations of lead in outdoor soil.  The EPA studies indicate that mining waste is the major
source contributing to the elevated lead levels in the soil.

18.    A commenter questioned whether Afton is an appropriate Reference Area for comparison with
       Picher because of obvious differences in ages and conditions of the homes and significant
       socio-economic differences.

Response:  For EPA's reply, see Technical Reply Document (Revised July 10, 1996), page 20,
section titled "Afton as a Reference Site."

19.    A comment was made that the sample size from the Reference Area (15 homes) is too small to
       draw any statistically valid or supportable conclusions.

Response:  The EPA disagrees.  The test of whether a sample size is large enough to be
"statistically valid" is whether it provides sufficient statistical power to detect differences
between sample groups with the desired level of confidence given the variability of the sample
sets and the magnitude of differences to be detected. The studies conducted by EPA revealed
highly significant differences in the concentrations of cadmium, lead, and zinc, the principal
contaminants associated with mining wastes, in yard soil and house dust between the Study Group
and Reference Area homes using standard, well accepted statistical methods (t-test, Mann-Whitney
U-test, and others).  Highly significant differences were also found between the Study Group and
Reference Area homes in the lead uptake from soil and dust, in the geometric mean blood lead
levels, and in the probability of blood lead levels exceeding 10 ug/dL predicted by the DELTBK
model.  These results indicate that the sample sizes used provided more than enough statistical
power, and, therefore, were "statistically valid."

20.    A comment was made that EPA argues in the Technical Reply Document (Revised July 10,  1996)
       that lead-based paint is not a significant source of soil lead contamination of
       residential soil based on a comparison of the paint chip data for Picher and Afton.

Response:  The commenter's statement is not an accurate description of EPA's position.  The EPA
believes that since the available data showed no significant difference in the prevalence or
concentration of lead in paint chips found in the two areas , lead paint was unlikely to account
for the order-of-magnitude difference in soil lead concentrations between the two areas.

21.    A comment was made that paint data from the Reference Area (4 exterior samples and 1
       interior sample)  are inadequate to support EPAs conclusion that lead-based paint is not a
       significant source of exposure in Picher and that the principal source of soil lead
       contamination is mining waste.

Response:  For EPA's reply, see Technical Reply Document (Revised July 10, 1996), pages 9-10.
The EPA has acknowledged the limitations of this data, but EPA maintains that the data that are
available provide no indication of any significant difference in the prevalence or concentration
of lead in paint chips found in the Study Group and Reference Area homes.

22.    A commenter pointed out that the Ottawa County blood lead investigation conductedby OSDH
       focused on communities in the northern part of the county, and complained that the
       Technical Reply Document implies that it was a county-wide study.

Response:  The EPA acknowledges that the OSDH blood lead investigation focused on the northern
part of Ottawa County, collecting samples in Picher, Quapaw, Commerce, Cardin, North Miami,  and
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Mami.   Based on the percentages reported by OSDH the total number of children tested (232) broke
down by community as follows:  84 from Picher, 72 from Miami, 32 from Commerce, 22 from Quapaw,
and 22 from others  (Cardin, North Mami, Afton, Grove, Fairland, Eucha, Wyandotte, and Welch).
As the Technical Reply Document points out, more than one third of those children were from
communities outside of EPA's Tar Creek Superfund site Study Area (72 from Miami plus at least 7
from the communities of North Miami, Afton, Grove,  Fairland, Eucha, Wyandotte, and Welch).  The
OSDH memorandum titled "Ottawa County Blood Lead Summary" presented summaries of the blood lead
results for all of the children tested, and a separate summary for Picher, where most of the
elevated blood leads (10 out of 15)  were found.  In the Technical Reply Document, EPA applied
the term "county-wide" to the blood lead results for all children tested to distinguish them
from the results for the Picher subgroup, and to make the point that statistics based on all 232
children were not representative of blood lead levels in the mining area as the Companies and
DOI had implied.

23.    A commenter suggested that the OSDH data can be modified to include just the mining area
       communities.

Response:  OSDH has not released the names and addresses of all blood lead survey participants.
However, based on a summary of elevated blood lead results  (10 ug/dL or greater) presented in
the OSDH memorandum, 12 of the children were from mining area communities  (10 from Picher and 2
from Commerce)  while 3 were from outside the mining area (2 from Miami and 1 from Grove).

24.    A commenter did not understand how EPA, if it regards the OSDH blood lead data as
       nonrepresentative and inappropriate for decision-making, can use the OSDH data to  conclude
       that there is a positive relationship between blood lead levels and exposure to mining
       related contamination.

Response:  The EPA has said only that the blood lead concentration levels found in children
living on the Site are consistent with the findings in EPA's BHHRA.  While not statistically
representative of the sampled populations, the OSDH blood lead data showed  that blood lead
levels of young children living in Picher, which is located at the main part of the Oklahoma
portion of the Tri-State Mining District, were clearly higher than in the other communities.
Ten of the fifteen children reported to have elevated blood lead levels (10 ug/dL or greater)
were Picher residents.   Based on the results of the Tar Creek Superfund site remedial
investigation,  residential soil lead concentrations in Picher also tend to be higher than in
other portions of the mining area, and much higher than soil lead concentrations outside the
mining area.  The soil lead concentrations in the Study Area showed highly significally positive
correlations with concentrations of cadmium and zinc, which indicate that mining waste is the
major source of the contamination.

25.    A comment was made that because the BHHRA evaluated only conditions in Picher,  it  is
       inappropriate to use the BHHRA to address other areas of the Tar Creek Superfund site.

Response:  Picher, which is at the main part of former mining activities in Ortawa County, was
intentionally selected for the BHHRA to determine whether high levels of environmental
contamination on the Site could pose significant human health risks.  The residential exposure
assumptions that were used to estimate exposures and risks in Picher are appropriate to use in
estimating the risk in other residential areas of the Tar Creek Superfund site.  The results of
the IEUBK modeling showed that the variables that were principally responsible for, the
predictions of elevated blood lead were elevated lead levels in soil and house dust.  There is
no reason that the conclusions and risk-based cleanup goals based on the Picher Study Group
should not be applied to homes in other parts of the Study Area where high levels of
environmental lead contamination were found.
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26.    A comment was made that it is inappropriate to compare the predictions of the IEUBK model,
       which did not account for all potential sources of lead exposure [the commenter seemed to
       be referring to paint chips], to OSDH's blood lead survey results for Picher.

Response:  The EPA has already explained in replies to previous comments why the OSDH blood lead
survey results were included in the BHHRA Report, and EPA has already discussed the reasons the
blood lead results and the IEUBK model predictions are not directly comparable.  See Technical
Reply Document  (Revised July 10, 1996), page 7, first and second paragraphs; and page 17,  third
paragraph.

27.    A comment was made that it is inappropriate for EPA to rely on the predictions of the
       IEUBK model when those predictions do not agree with the observational data  [the commenter
       seemed to be referring to the OSDH blood lead results].   The commenter maintains that the
       similarity between the IEUBK model predictions for the Picher Study Group,  which excluded
       possible paint chip ingestion,  and the Picher blood lead results reported by OSDH which
       necessarily reflect lead exposure from all sources demonstrates that the model predictions
       were wrong.  The commenter suggested that the observed blood lead levels should have been
       higher if the model predictions were accurate.

Response:  The EPA does not agree that the predictions of the IEUBK model conflict with any of
the measured blood lead data.  The blood lead results reported by OSDH while not directly
comparable, are not inconsistent with the predictions of the IEUBK model in the BHHRA.  The
blood lead test results reported by the OSDH do not demonstrate that the model results are
invalid.  There are other possible explanations as to why the observed blood lead levels from
the OSDH survey were not higher than the IEUBK model prediction in the BHHRA.  One possibility
is that lead-based paint is not a major source of lead exposure at the Site.  For discussion of
this point, see Technical Reply Document (Revised July 10, 1996), page 9, second paragraph
through page 12, second paragraph.  Another possibility is that the lead levels in environmental
media at the homes of the children in the OSDH blood lead survey were not comparable to EPA's
Study Group homes.

Preliminary results from a blood lead study conducted in 1996 by the University of Oklahoma for
certain mining companies  (CHAMP, July 1996 - October 1996) indicate that blood lead levels of
young children in Picher are actually higher than reported by OSDH.  The blood lead study, which
was a part of the mining companies' Community Health Action and Monitoring Program  (CHAMP),
reports that of 81 children tested in Picher, 38.3% had blood lead levels greater than or egual
to 10 ug/dL and 13.6% had blood levels greater than or egual to 15 ug/dL.  The percentages of
elevated blood lead levels reported for nearby Cardin are even higher.  The residential
properties included in EPA' s Study Group and the properties covered by the study may overlap,
but they are not the same, therefore the results from the two studies are not directly
comparable.  However, both should be reasonably representative of the community as a whole.  The
blood lead levels found in the CHAMP study are higher than those predicted by the IEUBK model;
as the commenter contends, they should be because the IEUBK model did not consider potential
lead intake from lead paint.  Therefore, the blood lead levels predicted by the IEUBK model are
consistent with the levels measured in the CHAMP study.

Another possible reason for the blood lead levels estimated by the IEUBK model being lower than
blood lead levels measured in Picher in the CHAMP study is that EPA may have used the low end of
the range of bioavailability of the lead on the Site.  The EPA ran the IEUBK model using the
default bioavailability assumption of 30%.   However, the information available regarding the
types of lead present in samples from the microprobe results (Drexler, 1996) indicates that most
of the lead actually found on the  Site was in the form of various oxides and carbonates.   Lead
oxides and lead carbonates are among the most soluble and bioavailable forms of  lead.  Further,
the microprobe results also showed that much of the lead oxides and lead carbonates present had
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very small particle sizes which would further enhance their solubility and bioavailabilities of
the EPA-assumed bioavailability of 30% possibly is on the low end of bioavailabilities of lead
present in yard soil from Picher.  Thirty percent is at the low end of the range of
bioavailabilities  (29 to 40%)measured for lead in soil from the Jasper County,  Missouri portion
of the Tri-State Mining District, using miniature swine(Casteel et al. 1996).

28.    A comment was made that the available blood lead data demonstrate that there is no
       emergency risk to public health and welfare from lead and suggest that EPA' s planned
       removal of residential yard soil is technically insupportable.

Response:  Previously, the Companies and DOI had suggested that because most of the elevated
blood lead levels reported by OSDH fell in the 10-14 ug/dL range, EPA's planned response action
was unnecessary and inconsistent with CDC gudelines.  The EPA disagreed and pointed out that CDC
guidelines recommend community-wide lead poisoning prevention activities when many children have
blood lead levels in the 10-14 ug/dL range.  See Technical Reply Document (Revised July 10,
1996), pages 4-5, item 3.

The 1996 blood lead data, gathered by the Companies, indicate that blood lead levels are
actually higher than were reported by the OSDH study.  That investigation found blood lead
levels above 10 ug/dL in more than 30% of the children tested:  38% of those living in Picher,
62% of those living in Cardin and 13% of those living in Quapaw.  It also found blood lead
levels above 15 ug/dL in many of the children:  11 children from Picher (13.6%), 3 children from
Cardin (18.8%), and 4 children from Quapaw  (6.0%).

The highest blood lead level, found in Cardin, was 32 ug/dL, a level at which the CDC recommends
medical evaluation, environmental investigation and remediation, and medical follow-up. The data
confirm that there is a significant public health risk from lead at the Tar Creek Superfund
site.

29.    A comment was made that EPA has presented no data to demonstrate that the bulk of
       environmental-media lead exposures are related to mining.  The commenter pointed out that
       the mineralogy characterization conducted by Dr.  Burke Burkart (Burkart,  July 6, 1995 and
       Burkart, September 23, 1995)  and the microprobe analyses conducted by Dr. John Drexler
       (Drexler,  1996) indicate that the two primary sources of lead in the residential soil are
       smelter wastes and lead-based paint, not mining waste.

Response:  To support its position that Mining waste is the primary source of lead contamination
in soil at the Tar Creek Superfund site, EPA has already made the following points in its
Technical Reply Document (Revised July 10, 1996), pages 9-10:

              Concentrations  of lead in soil in the at the Site exhibited highly significant
              positive correlations  with cadmium and zinc concentrations.   Cadmium,  lead,
              and zinc are  the elements primarily associated with area mining wastes,  and
              they serve as a signature for the presence  of mining waste in environmental
              media at the  Site.

              The concentrations  of  lead in residential  soil in the Study Area  were
              proportionate to cadmium and zinc concentrations in the  soil.   Lead
              concentrations  were not disproportionately  elevated as would be expected if
              there were other major sources of lead contamination other than mining waste,
              such as lead-based  paint.

              The median and  average concentrations of cadmium,  lead,  and zinc  in
              residential soil were  each approximately an order of magnitude higher in the
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              Study Group (near the center of former mining activities)  than in the
              Reference Area (outside the mining area).

              Lead-based paint was found in approximately the same proportion of Study Group
              and Reference Area homes,  indicating that  paint is not likely to account for a
              significant part of the difference in soil lead concentrations between the two
              groups of homes.

Further, when Dames & Moore  (the Companies' environmental consultant) resampled 8 properties
previously sampled by Ecology & Environment  (E&E) (EPA1 s environmental contractor), Dames & Moore
explicitly identified chat  (i.e., the coarser fraction mining waste from milling operations) in
a substantial number of soil samples, and noted that a number of these properties had driveways
surfaced with chat.

Electron microprobe results for 12 samples from Picher were included in a report by Dr. John
Drexler (Drexler, 1996).  Two chat pile samples, one roadway sample and 9 composite soil samples
from residential properties that included egual parts of soil from front yards, backyards, and
drip lines were examined.  Several groups of lead-bearing minerals were found:

          Galena  (PbS), the primary  lead-bearing mineral in  the  ore mined in  the
          Tri-State Mining  District,

          Cerussite  (PbCOS), a weathering product  of galena  and  a lead compound used
          in  lead-based paint;

          Anglesite  (PbS04), a weathering product  of galena;

          Lead Oxide  (PbO), a weathering product  of galena and a lead compound often
          used in lead-based paint;

          Lead-Metal Oxides  (Pb(M)O), oxides of lead and other metals - most  often
          copper, occasionally antimony; associated with smelter operations at other
          sites,

          Iron-Lead and Manganese-Lead Oxides  (Fe-Pb and Mn-Pb Oxides), which are
          secondary weathering products formed in  situ  in soil by the adsorption  of
          soluble lead  compounds by  iron and lead  oxides naturally present  in soil;

          Other lead-bearing paint pigments  (PbTi02, PbCr04)

On a relative mass basis, the lead in the chat pile samples was predominately  cerussite (89 and
76%)  with some galena  (0 and 22%), Fe-Pb Oxide (5 and 1%),  zinc oxide containing lead  (4 and
1%),  and anglesite  (2 and 1%).

The soil samples averaged 44%(range: 18-59%)lead-metal oxides and 29% (range:  3-63%) secondary
weathering products.  Lead-metal oxides have been associated with smelter emissions at other
sites; however,  the only smelter confirmed to have operated at the Site,  based on available
historical information, was the Ontario Smelting Company/Eagle-Picher smelter, which was
relatively small and which operated for only about 15 years  (1918 until the early 1930s).   It
was located south of Hockerville, about 3 miles east of Picher in a cross wind or down wind
direction under prevailing wind conditions, too far away to account for the average soil lead
levels found in Picher  soil.  No smelter has been identified in the Picher area that could
account for the lead levels found in soil at the Tar Creek Superfund site.  Therefore,
attributing the lead in soil at the Tar Creek Superfund site to a smelter source is inconsistent
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with the available historical information.

Four of the samples contained cerussite(16, 33, 34, and 78%), however the cerussite was
positively attributed to paint only in the sample containing 78% cerussite,   The cerussite in 3
of the samples and the secondary weathering products in all of the samples is of a type that is
known to be found in mining and/or milling wastes.  The origin of the lead-metal oxides is
presently unknown, but may be from milling waste altered in the environment.  One of the yard
soil samples  (#502) contained galena (12%) and its two principal weathering products, anglesite
(12%) and cerussite (16%), which is consistent with a chat source.

The single roadway sample was predominately galena (65%) with some cerussite (18%), lead-metal
oxide (5%), PbSi04 (4%), PbC12 (3%), and Fe-Pb oxide(2%).  The EPA understands that the roadway
was surfaced with chat and the microprobe results are consistent with a chat source.

30.    A commenter said that OSDH conducted an environmental assessment and collected
       environmental  samples at each residence at which a child had a blood lead level greater
       than 10 ug/dL.   The commenter reguested that EPA obtain the data and guantitatively
       evaluate relationships between lead in the environmental media and blood lead levels.

Response:  OSDH's environmental assessment follow-up in conjunction with its blood lead
investigation was discontinued after the homes of only a few children were assessed.  The OSDH
environmental assessments were discontinued when the CHAMP study, which also included
environmental assessments, was proposed.   Also, the OSDH sampling locations were selected based
on professional judgment rather than a more systematic sampling approach.  The limited OSDH
sampling that was conducted was not designed for the type of guantitative evaluation suggested
by the commenter, nor would it likely be suitable for such use.

31.    A commenter notes that as  part of the CHAMP, the University of Oklahoma is collecting
       matched blood  lead and environmental samples at more than 100 residences at the Tar Creek
       Superfund site.  The commenter recommends that EPA forego planning and implementing
       additional remedial activities until the results of that investigation are available.

Response:  While the  pending results of the investigation are of interest, EPA believes that the
residential soil lead contamination  (which existing evidence indicates is primarily from mining
waste)  at the Site poses a significant public health hazard that warrants the planned remedial
response action.

32.    A comment was  made that the second paragraph on page 7 of the Technical Reply Document
       attempts to use the IEUBK model-predicted results to support a conclusion that lead-based
       paint is not a primary source of lead exposure in Picher.

Response:  The paragraph cited puts forth two possible reasons that blood lead levels reported
by OSDH were not higher that the IEUBK model predictions, as would be expected if paint was a
significant source of lead exposure. One possibility was that the children in the blood lead
survey were not exposed to environmental  (non-paint)  lead concentrations as high as those
measured at the Picher Study Group homes.  The second possibility, if lead levels in
environmental media at the OSDH survey homes and the BHHRA Study Group homes were comparable,
was that paint chips  were not a significant source of lead exposure.  The more recent blood lead
survey indicates that blood lead levels in Picher are actually higher than the IEUBK model
predictions.  That difference is not inconsistent with exposures to lead from other sources,
such as lead-based paint, in addition to lead in environmental media.  See Comment 27, above.

33.    A comment was  made that the BHHRA Report acknowledges that if the concentrations of
       lead-based paint measured in the 100 Study Group homes are included as inputs to the IEUBK
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       model,  then lead-based paint becomes the primary cause of the predicted elevated blood
       lead levels and soil and dust are reduced to minor contributors.

Response:  Outdoor paint was sampled from just 52 of the 100 Study Group homes, and the lead
concentrations at 23 of those homes were below the 5000 milligrams per kilogram (mg/kg)
criterion used by HUD for lead-based paint.  The mean and median lead concentrations found in
outdoor paint at the Study Group homes were approximately 20,000 mg/kg and 3500 mg/kg,
respectively.   For comparison, outdoor paint was sampled from 4 of the 15 Reference Area homes,
and only one had a lead concentration less than 5000 mg/kg.  The mean and median lead
concentrations found in outdoor paint from the Reference Area were both greater than 35,000
mg/kg.  These data indicate that the prevalence of lead paint and, therefore, the potential
exposures to lead from this source are not significantly greater in the Study Group homes
compared to the Reference Area homes.  That is, lead paint on the Site does not explain the
order of magnitude difference in soil lead concentrations between the Study Group homes and the
Reference Area homes.

The BHHRA Report acknowledged that ingestion of paint chips could be a major route of lead
exposure in homes where children have access to deteriorated or damaged lead-based paint.  It
also explained that there is a great deal of uncertainty about the amount of paint chips young
children routinely ingest.  Since paint chips can have very high concentrations of lead compared
to the levels typically found in soil and house dust, the IEUBK model is very sensitive to the
assumptions made about the guantity of paint chips ingested.  Inclusion of this highly uncertain
exposure pathway in the model would have a major impact on the total lead uptake estimated by
the IEUBK model, potentially overwhelming the contributions from all other sources.  For these
reasons, the IEUBK model guidance manual (EPA, February 1994) recommends against including
direct paint chip ingestion in the model unless site-specific information is available about the
pathway.  Therefore, the paint chip data were excluded from the guantitative evaluation in the
BHHRA for both the Study Group and the Reference Area homes in order to focus on the potential
health risks from environmental site-related contamination, not lead-based paint.

The BHHRA found that soil lead contamination on the Site was high enough that soil lead alone
posed a significant risk to children's health.  The above points are discussed thoroughly in the
uncertainty section of the BHHRA Report (Section 5.4.1 1) and in the Technical Reply Document
(Revised July 10, 1996), page 6, second paragraph and page 17, second paragraph.

34.    A comment was made that it is inappropriate to ignore the lead-based paint  data to make
       the IEUBK model predictions support EPA' s position that mining related materials are the
       explanatory variable for the observed blood lead elevations at the Tar Creek Superfund
       site.

Response:  See Technical Reply Document (Revised July 10, 1996), page 17, third paragraph
through page 18, first paragraph, and items 33, and 47 of this response document.

35.    A comment was made that the Lead and Cadmium Exposure Study for the Jasper  County Site
       (ATSDR,  February 1995)  indicated that blood lead levels were positively correlated with
       parameters other than soil lead concentrations,  and that follow-up investigations by the
       Jasper County and Joplin Health Departments found other primary sources of  lead exposure
       including paint (Jasper County is not part of the Site).   The commenter also stated that
       investigations of the Companies and EPA Region 7 have established that smelter emissions
       and lead-based paint are key contributors to lead in soil at both the Cherokee County,
       Kansas  and Jasper County, Missouri sites.  The commenter wondered how, in light of this
       evidence, EPA can continue to insist that mining waste is the primary culprit at the Tar
       Creek Superfund site.
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The Jasper County study (ATSDR, February 1995)  indicated that blood lead levels were
significantly higher in the exposed group within the mining area compared to a control group
outside the mining area, and that exposure to soil was the most important factor influencing the
distribution of blood lead levels between the two groups.

At least three smelters were known to have operated in the Jasper County and Cherokee County
portions of the Tri-State Mining District.  These were located in Galena, Joplin,  and Oronogo.
The soil impacted by these smelters was found to be limited to properties within about 1-2 miles
of these smelters.  Smelters were not considered a source of lead for properties located greater
distances from smelters.  The only known smelter in the vicinity of Picher was the
Ontario/Eagle-Picher smelter located south of Hockerville, about three miles east of Picher in a
cross wind or downwind direction from Picher.  Therefore, by the criteria used at the Jasper
County and Cherokee County sites, smelters would not be considered a source of lead in soil at
properties in Picher.  The presence of elevated lead concentrations in the absence of
correspondingly high cadmium and zinc levels was considered to be another indication that the
lead for the Jasper County and Cherokee County sites might be from a smelter or lead-based
paint.  In contrast lead concentrations in soil in Picher correlated well with both cadmium and
zinc concentrations, which means that the source of that lead is more likely than not to be
milling waste and not smelter waste(or lead paint for that matter).

At the Jasper County and Cherokee County sites, lead-based paint was considered to be the
suspected source of elevated soil lead levels if Elevated lead levels were found without a
corresponding elevation of cadmium and zinc levels, The property was more than one mile from the
nearest smelter, Paint chips were observed in soil surrounding an older home.

Observation of paint chips in soil is circumstantial evidence, at best, of a lead source.  The
paint chips may not contain lead-based paint, and even if they do,  there is no practical and
certain way of knowing what fraction of the lead in the soil is from the paint chips. Lead-based
paint has not been proven, to be a major source of elevated soil lead levels.

36.    A commenter disagreed with the argument  that elevated concentrations of lead in soil are
       attributable to mining waste because the associated elevated concentrations of zinc and
       cadmium cannot be attributed to paint.  The commenter pointed out that zinc and cadmium
       have been used and are still used in various paints,  and there are numerous other sources
       (not specified).

Response:  Although there are numerous sources  of lead, cadmium, and zinc, the highly
significant positive correlations between the concentrations of these contaminants in Site soil
indicates that they are from the same major source, and the most likely candidate is mining
waste.  Even if cadmium and zinc were used in paint (or other products), as the commenter
suggests, the amounts of these metals in the products relative to lead would vary widely.  And
if many different paints were the major sources of environmental lead contamination, the
relationship between cadmium, lead, and zinc concentrations in soil would also vary widely and,
a significant correlation site-wide would be unlikely.  The fact is that the correlation between
lead, zinc and cadmium contamination is consistent throughout the Site and consistent with
contamination from mining waste, and consistent with lead from paint.

37.    A commenter questioned the validity of EPA's comparisons of average lead concentrations  in
       indoor dust concentrations to lead concentrations in outdoor soil, contending that the
       outdoor soil averages are biased high by the inclusion of drip line samples which
       frequently had elevated concentrations,  and EPA's conclusion that indoor lead paint was
       not the source of the lead measured in dust.

Response:  The EPA's Technical Reply Document  (Revised July 10, 1996), page 10, second paragraph
-------
stated that 45 of the 50 Study Group homes with average dust lead concentrations greater than
200 mg/kg  (the upper-end estimate for background)  had even higher lead concentrations in yard
soil, which suggests that soil, not indoor paint,  was the source.  The EPA acknowledges that
some outdoor soil lead averages were increased by the inclusion of drip line soil results,  but
the effect is not as great as the commenter implies.  Fewer than 20% of the Study Group homes
showed drip line soil lead concentrations that were substantially elevated in comparison to the
other yard soil samples  (front yard, backyard, and play area).   It should be noted that elevated
lead concentrations at the drip line may reflect not only lead-based paint, but also deposition
of airborne lead on the home.  If the drip line results are excluded from the soil averages,
then 43 of the 50 Study Group homes with average dust lead concentrations greater than 200 mg/kg
had even higher lead concentrations in yard soil.

38.    A commenter claimed that EPA attempts to discredit the ATSDR follow-up investigation to
       the 1993 Indian Health Service (IHS)  blood lead data and ignores its conclusions because
       they are contrary to EPA' s position on the causes of elevated blood lead levels in Native
       Americans.

Response:  The EPA did not attempt to discredit the ATSDR study.  The EPA simply laid out what
the ATSDR study did and did not say.  The EPA's position is that elevated blood lead levels may
result from exposure to high concentrations of lead in soil related to former mining operations
in the area.  The ATSDR investigation does not conflict with that position.  ATSDR identified
significant sources of lead exposure at two houses: exterior paint and soil at one house, and
exterior paint and house dust at another.  No significant sources of lead were identified at the
other seven homes investigated.  However, as pointed out in the Technical Reply Document
(Revised July 10,  1996), page 12, that does not mean that significant sources did not exist.
For example, lead concentrations exceeding 400 mg/kg were detected in composite soil samples
from four of  the homes, and those composite results may substantially understate soil lead
concentrations in some areas of the properties.  Also, house dust with lead concentrations
greater than 200 mg/kg was detected in 6 out of the 9 homes surveyed by ATSDR.  House dust lead
concentrations greater than 200 mg/kg can have a noticeable impact on predictions by the IEBUK
model of children's blood lead levels.

39.    A comment was made that the IHS blood lead data do not  support the conclusion that 35
       percent of the Native American children living at the Site have elevated blood lead
       levels,  as implied by EPA.

The EPA has never claimed that the IHS blood lead data show that 35% of Native American children
living at the Site have elevated blood lead levels.  The EPA has stated in the Five Year Review
Report, the BHHRA Report, and the Technical Reply Document that the IHS blood lead data
indicated that 35% of the children tested had blood lead levels greater than or egual to 10
ug/dL.

40.    A comment was made that EPA's site-wide response is based on the IHS blood lead data.

Response:  The comment is not accurate.   The EPA's time-critical removal actions were based on
extensive removal site assessment investigations.   The EPA used the IHS blood lead data as a
"warning beacon."  That is, EPA used the IHS blood lead data as a finding that indicated the
need for more thorough follow-up investigations at the Site.  It was the follow-up site
assessment investigations which were the basis for the EPA removal actions at the Site, and not
the IHS blood lead data which only indicated the need for further study.

41.    A commenter alleged that the yard soil data collected by E&E at the Tar Creek Superfund
       site are extremely biased and unrepresentative because  of sampling and compositing
       procedures used,  and that the mean lead concentrations  in soil reported by E&E are more
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       than twice as high as the "true" mean measured in the Dames & Moore resampling effort.

Response:  A detailed comparison and discussion of the E&E and Dames & Moore studies is provided
later in this detailed response document.  A summary of a few of the more important points
follows.

First, the mean result reported by Dames & Moore is not a "true" mean, because the true mean can
never be determined by any sampling effort; rather, it is an estimate of the mean, as is the
mean of the sample reported by E&E.  Secondly,  the two studies measured different things; the
E&E study measured the lead concentrations in the top 1 inch of soil, while the Dames & Moore
study measured lead concentrations in the top 2 inches of soil. This difference may account for
part of the difference in the results of the  two studies.  The methodology used by E&E is
commonly used in investigating Superfund sites, and, in fact, is very similar to the methodology
used by Dames & Moore in its investigation of the Jasper and Cherokee Counties portion of the
Tri-State Mining District on behalf of EPA Region VII.  In that study, Dames & Moore concluded
that the sampling methodology it employed was reproducible and gave representative results.  At
the Tar Creek Superfund site, C.C. Johnson & Malhotra, P.C.   (CCJM) also resampled properties
previously sampled by E&E using the same sampling design as E&E (0-1 inch composite samples).
Composite samples are samples composed of subsamples from different locations combined and mixed
together.  CCJM's results were statistically indistinguishable from E&E's results and, like
E&E's results, were statistically significantly different from Dames & Moore's results.  This
finding indicates that the sampling methodology used by E&E was reproducible and reliable, and
suggests that there must be some other reason for the differences in the results obtained by E&E
and CCJM, on one hand, and Dames & Moore on the other.  The difference in the depth from which
samples were collected is one reason, and difference in the sampling designs employed is
another.   In the E&E and CCJM studies, drip line area subsamples always comprised one guarter to
one third of the total yard soil sample, depending on whether a property had an identifiable
play area that was sampled in addition to the front yard, backyard and drip line areas.  Drip
line areas often have higher lead levels than general yard samples because particles deposited
on roofs and paint chips from the house exterior tend to accumulate in these areas, therefore
E&E's sampling plan was designed to ensure that these areas were always sampled.  In contrast,
drip line areas were not sampled at 3 of the 8  properties resampled by Dames & Moore and
represented only 5 to 20% of the samples at the remaining 5 properties.

The EPA believes that the difference between the E&E and Dames & Moore results resulted from
differences in what was sampled in the two studies, not from any bias or unrepresentativeness in
E&E's sampling and compositing procedures.

42.    A commenter agreed that another source other than lead paint and automobile exhaust is
       needed to explain why the lead in soil in the Study Group homes is approximately 10 times
       higher than in the Reference Area homes, but argued that mining waste is not the source
       because:

       •     Soil lead is 10-30 times higher in Picher than in Baxter Springs and Treece, Kansas;

       •     The average lead concentration in Picher yards is twice as high as the average lead
            concentration reported for chat at  the Cherokee County, Kansas and Jasper County,
            Missouri sites; and

       •     Lead speciation suggests that the source is smelter emissions or smelter wastes and
            that is consistent with findings near other Eagle-Picher smelter locations.

Response:  There is considerable variability in the concentration of lead in chat from the piles
around Picher as the results of the Dames & Moore resampling study show  (see the Lead in Chat
-------
section of the discussion of the D&M study below).   The lead concentrations in some of the chat
are quite sufficient to account for the lead levels found in soil.

Some of the lead species found in soil at the Tar Creek Superfund site have beenassociated with
smelters at other sites, however, no smelter has been identified in the Picher area that could
account for the lead levels found in soil at the Site.  Moreover, the lead species in question
(i.e., the lead species which may be attributed to smelters) may also be attributable to other
non-smelter sources such as weatherinq products of chat interactinq with the soil at the Site.
Therefore, attributinq the lead in soil at the Site to a smelter source is not adequately
supported and is inconsistent with the available historical information and the direct
observation by many of siqnificant quantities of chat in the yards.

43.    A commenter noted that lead-based paint was  identified as the principal source of lead
       exposure contributinq to blood lead levels  nation wide,  and suqqested that it also is a
       major source at the Tar Creek Superfund site.

Response:  Lead-based paint may well be the major source of lead exposure in areas without a
siqnificant local industrial source of lead.  However, at the Tar Creek Superfund site,  there is
a major local source, the mininq and milling wastes that dominate the area.  The weight of
evidence from EPA's extensive environmental investiqation indicates that the major source of
lead exposure at the Tar Creek Superfund site is soil contamination resultinq from the storaqe
of mininq and milling wastes in the area and the use of these wastes as fill and for surfacing
local roads, driveways, and parkinq lots.

44.    A comment was made that the blood lead levels observed in the OSDH investiqation - where
       more than 60% of the children had very low blood lead levels - is not consistent with a
       widespread source of lead such as yard soil.

Response:  The OSDH study and EPA's investiqation of the Tar Creek Superfund site cover
different qeoqraphical areas.  A substantial portion of the subjects in the OSDH study live
outside the mininq area, thus their residences are not included in EPA's Study Group or Study
Area, and, consequently, their blood lead levels would not be affected by lead levels in yard
soil in the mininq area.

45.    A commenter stated that 80% of the Study Area properties have soil lead levels above the
       level that the IEUBK model indicates is a cause for blood lead levels to be above 10
       uq/dL.

Response:  This is not correct.  About 80% of the Study Group homes have soil lead levels
qreater than 500 mq/kq.  This 500 mq/kq soil lead concentration level is a level correspondinq
with a 5% chance of a child livinq at the residence in question havinq a blood lead level of 10
uq/dL or hiqher.  The IEBUK model does not predict that a child currently livinq at a particular
residence will definitely have a blood lead level above 10 uq/dL. As discussed in the BHHRA
Report and shown in Table 5- 1, the soil lead concentrations measured at the Study Group homes
are predicted by the IEBUK model to result in about 20% of the children livinq in the community
havinq blood lead levels qreater than 10 uq/dL, a prediction that is consistent with the
measured blood lead levels of younq children livinq in Picher.

46.    A commenter noted that EPA's procedures for  evaluatinq the Tar Creek Superfund site and
       selectinq a course of action do not necessarily correspond to CDC's quidelines for
       addressinq lead contaminated sites.

Response:  The EPA disaqrees that its activities are inconsistent with the CDC quidelines.  For
EPA's response to a previous similar comment, see Technical Reply Document  (Revised July 10,
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1996, page 4, Reply #3 to General Comments) .   The EPA's procedures also follow its own
guidelines set forth in OSWER Directive 9355.4-12, revised July 14, 1994,  for addressing CERCLA
sites and RCRA Corrective Action Facilities having lead contamination.  Three key elements of
OSWER Directive 9355.4-12 are as follows:

       (1)     OSWER will attempt to limit exposure to soil lead levels such that a typical(or
              hypothetical)  child or group of similarly exposed children would have an estimated
              risk of no more than 5% of exceeding the 10  ug/dL blood lead level.   The 10  ug/dL
              blood lead level is based on analyses conducted by the  CDC and EPA that associate
              blood lead levels of 10 ug/dL and higher with health effects in children.

       (2)     In developing Preliminary Remediation Goals  (PRGs)  for  CERCLA sites,  EPA recommends
              that soil lead concentrations be determined  so that a typical child or group of
              children exposed to lead at this level would have an estimated risk of no more  than
              5% of exceeding a blood lead of 10 ug/dL.   In applying  the IEUBK model for this
              purpose,  appropriate site-specific data on model input  parameters,  including
              background exposures to lead, would be identified.

       (3)     A suggested decision procedure  is recommended which includes collecting
              site-specific data,  running the IEBUK model  with the site-specific data if soil lead
              levels are greater than 400 mg/kg,  and where risks are  significant (greater  than a
              5% risk of blood lead levels exceeding 10 ug/dL),  evaluating remedial options.

47.    A commenter raised concerns about how  potential exposure to lead that might ultimately be
       traceable to lead paint was dealt with in the IEUBK model used in the risk assessment.

Response:  Samples of yard soil and indoor dust were collected from each of the Study Group
homes and were analyzed for lead and other metals.  The measured lead concentrations in these
media were used directly as inputs to the IEUBK model.  The yard soil concentrations were the
arithmetic average of the concentrations found in the minus 250 Im fraction of composite soil
samples collected separately from the front yard, backyard, drip line, driveway, and play area.
Since drip line soil, which often contain paint chips that have been scraped or have fallen from
exterior surfaces, were explicitly sampled and included in the average value for yard soil as a
whole, lead from any paint chips that had been incorporated into this soil was taken into
account in the IEUBK model.  Similarly, any lead from indoor paint that had become incorporated
into the indoor house dust would be reflected in the lead concentrations measured in house dust
and, thus,  lead paint from this exposure mechanism would be taken into account in the IEUBK
model,

In addition to standard inputs for lead concentrations in yard soil and house dust, the IEUBK
model provides an optional input for lead concentrations in paint chips.  According to the IEUBK
model user's guide  (EPA, February 1994), this input is provided to allow the user to incorporate
lead exposure from direct, long-term ingestion of paint chips into the IEUBK model in addition
to the standard inputs for yard soil and house dust.  However the guide cautions that
information on the amount of paint chips a child typically ingests on a long-term basis is
sparse and highly uncertain, much more uncertain than estimates of the amount of soil/house dust
a child might ingest.  The user's guide concludes its discussion of the optional lead paint
input as follows:

       In view of the lower guality of information on paint chip intake than on intake of
       soil,  dust, dirt, or drinking water, and the usefulness of providing baseline risk
       assessments in the absence of lead-based paint, we  have used a default value of 0
       ug/dL in the model.
-------
Thus, EPA Region VI's decision not to include a separate input for ingestion of discrete paint
chips (apart from paint that may have been incorporated into soil and house dust)  is completely
consistent with the recommended use of the IEUBK model.  Moreover, it should be noted that,  if
EPA had entered estimated-paint chip consumption figures into the model,  then the risk to
children predicted by the model would increase.

48.    With regard to the use of the minus 250 Im fraction of soil in the risk assessment,  a
       commenter stated that fine particles are more likely to be transmitted from hand to mouth
       and absorbed in the gut,  but that the data should be corrected for skin adherence relative
       to whole soil,  or else the percentage represented by whole soil should be used.

Response:  The EPA disagrees. A soil adherence factor should be used in estimating exposure to a
soil contaminant via dermal absorption,  but should not be used in estimating exposure via
incidental ingestion  (hand-to-mouth contact).   Dermal absorption is not considered a significant
route of exposure for lead in soil.  Soil ingestion is estimated directly as a certain amount
(number of milligrams) of soil ingested per day.  There is no intermediate calculation relating
the amount of soil ingested to the amount of soil adhering to a certain skin area, therefore
there is no need for a soil adherence factor.    There is general recognition among scientists
who study exposure to contaminants in soil that fine soil particles preferentially adhere to the
skin (which the commenter acknowledges)  and thus is the fraction most likely to be ingested.
That being the case,  the best estimate of the amount of contaminant ingested via hand-to-mouth
contact would be obtained by directly measuring the concentration of the contaminant in the fine
fraction that is being ingested  as was done in the EPA study.  Since the contaminant
concentration was measured in the soil fraction being ingested (i.e., in the fines), no
proportionality factor or percentage adjustment involving the whole soil is reguired.

49.    A comment was  made that EPA failed to follow its own guidance recommending that the
       multi-media/multi-source nature of lead contamination be considered in managing risks from
       lead exposures.

Response:  The EPA disagrees.  The EPA collected and analyzed samples of soil, house dust,  tap
water,  home-grown produce, and air as part of its investigation of the Study Group homes.  The
lead concentrations found in each of these media (except air which had concentrations below its
assumed default concentration) were used directly in the IEUBK model.  The model results,
therefore reflect the multi-media/multi-source nature of lead exposure.  The estimated
contributions of each of these sources were clearly identified in the risk assessment,  and were
considered in the risk management decisions that were made.  Potential exposure to lead derived
from paint was considered in accordance with the guidance on the appropriate use of the IEUBK
model as discussed in EPA's response to item 47.

50.    A comment was  made that since some of the residents may not have fully complied with EPA's
       reguest not to use their tap water until a "first draw" sample could be collected, EPA may
       have overlooked a significant source of lead exposure.

Response:  As the comment itself shows,  EPA did not overlook the issue of first draw water,  and
in fact collected data on first draw water to the extent cooperation of the occupants of a
residence allowed.  Higher lead concentrations were found in many of the reputed "first draw"
samples compared to the "flushed" samples indicating that most of the residents complied with
the reguest.  In any event, drinking water proved to be a very minor source of lead exposure,
contributing only an estimated 2% to the total estimated exposure (see BHHRA Report, Figure
5-1) .

51.    A commenter asserted that nearly every exterior paint sample contained large amounts  of
       lead.
-------
Response:  This is not correct, More than half of the samples  (28 out of 52) from Study Group
homes had lead levels below 5,000 mg/kg, the standard used by HUD for lead in paint.

RESPONSE TO ISSUES RAISED IN THE DAMES & MOORE REPORT ON IiEAD IN YARD SOILS INCLUDED AS
ATTACHMENT TO GARY UPHOFFS LETTER OF OCTOBER 22,1996

Synopsis of the Dames & Moore  (D&M) Studies:

       Dames & Moore is an environmental engineering consultant who was hired by a group of
companies which once owed or operated mining or milling concerns on the Site.  On behalf of the
mining companies, D&M resampled eight residential properties that were previously sampled by E&E
(E&E is EPA's environmental engineering contractor).  C.C. Johnson and Malhotra, P.C.  (CCJM)
also resampled these properties on behalf of DOI's Bureau of Land Management (BLM).

       E&E's sampling plan divided each property into up to six sampling areas,  or "strata":  The
front yard, backyard, drip line, driveway, play area, and garden.  Five or six subsamples were
collected from a depth of 0 to 1 inch in each of the sampling areas.  The subsamples were
collected from the four comers and the center of each area except for drip he samples which were
located in evenly spaced lines along the drip fine.  The subsamples were composited to obtain a
single composite sample for each area   (compositing means combining subsamples from different
locations).  The composite samples were air dried and passed through a 10-mesh screen to remove
pebbles and debris.  The minus 10-mesh fraction was analyzed by using a Spectrace 9000 X-ray
fluorescence  (XRF) spectrophotometer.   The samples were then passed through a 60- mesh screen to
obtain a minus 250 micron fraction which was sent to a laboratory for standard EPA Contract
Laboratory Program  (CLP) Inductively Coupled Plasma  (ICP) analysis.  For risk assessment
purposes, E&E calculated total yard soil lead concentrations by arithmetically averaging the
laboratory results for all sampling areas, except gardens.

       D&M used a stratified systematic grid sampling scheme in which grids were laid out in
contiguous portions of the property: front, back,  and side yards, driveways, play areas, and
gardens; 45 to 75 discrete samples were then collected from a depth of 0 to 2 inches at grid
nodes.  Any grass, twigs, or rock fragments greater than 1/4-inch in diameter were removed by
hand then each of the discrete samples was analyzed using a Metorex X Met 920 XRF
spectrophotometer.  Confirmatory laboratory analyses were performed on a randomly selected
subset of the samples.  Average yard soil concentrations were calculated by arithmetically
averaging the results for the discrete samples from the yard and any play areas present.

       C.C. Johnson and Malhotra,  P.C.  used a sampling scheme identical to that used by E&E
except that a single composite sample was prepared from the subsamples collected from the front
yard, backyard, drip line and play area.  Whole soil, and minus 1 mm and minus 250 micron
fractions were analyzed using standard laboratory methods.

Issues Raised:

       a.     Sampling Strategy

       The D&M report suggests that differences in the sampling strategies used by E&E and D&M
are responsible for significant differences in the results.

       E&E's sampling plan employed a  stratified systematic sampling design which is one of the
common sampling designs described in EPA guidance  (EPA 1992, Exhibit 44).   Each of the strata
had discrete properties that were potentially important in evaluation potential lead exposure at
the properties, therefore specifically sampling each of these strata was one of the objectives
of the sampling plan.
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       E&E's sampling plan was very similar to the sampling plan proposed by D&M and approved by
EPA Region VII for investigating residential properties in the Kansas and Missouri portion of
the Tri-State Mining District which is off of the Site and located in EPA Region VII.  That plan
also provided for separate composite samples from up to three yard areas (designated as front,
back, and side), driveways, play areas, and gardens.  The Region VII sampling plan provided for
3 or 4 subsamples; from each area generally laid out in a rectangle or a line depending on the
geometry of the area being sampled.  This also would be considered a stratified systematic
sampling design.  In the report presenting the results of Jasper and Cherokee Counties study,
D&M observed that duplicate samples collected in this fashion gave relative percent differences
of 0 to 22% and conclude that the subsampling and compositing method yielded representative
results (D&M, 1994).

       Comparison of the lead concentrations in similar soil samples collected at the Tar Creek
Site and analyzed by E&E, CCJM and D&M using t-tests for paired samples showed that the E&E and
CCJM results were not significantly different from one another, however the D&M result were
significantly different from both the E&E and CCJM results.  The agreement between the E&E and
CCJM results indicates that the 5 or 6 point composite sampling strategy employed is
reproducible and yields representative results.  This finding also is consistent with D&M's
conclusions about this type of sampling in the Cherokee and Jasper County portion of the
Tri-State Mining District in EPA Region VII.  Thus the differences between the E&E and CCJM
results,  on the one hand, and the D&M results, on the other, are not likely to be related to the
number of samples collected from an area; they are more likely to be due to the different depths
from which samples were collected and the proportion of drip line samples included in the D&M
sample sets.

       Some of the differences between the E&E and D&M results are due to the differences in the
way the two studies dealt with drip lines.  No drip line samples were collected from three of
the properties resampled by D&M and only 2 out of 51 samples collected from another property
were from the drip line.  Ten to 20% of the D&M samples were from drip line areas at the other 4
residences.  The E&E results show that at 4 of the 8 properties resampled by D&M the lead
concentrations in the drip line samples, were 2.5 to 4 times higher than in the general yard
soil.  The lead concentrations found in drip line soil significantly increased the estimates of
average yard soil lead concentrations for these residences.  However, the lead concentrations in
just the front yards and backyards of these residences, excluding the drip line concentrations,
still averaged about 1,500 mg/kg in the E&E study.  Lead concentrations in just the front yards
and backyards, excluding the drip lines, exceeded 500 mg/kg at all 8 of these residences, and
exceeded 1250 mg/kg at 5 of the residences.  In contrast the average lead concentration found in
yard soil alone (excluding drip line samples)  by D&M was about 870 mg/kg.  The difference in the
treatment of drip line areas contributes to the different results obtained but it does not
appear to be the most important factor.  In most cases, EPA would have made the same remedial
decision to deal with the soil lead, even if the drip line areas were ignored because the lead
concentrations in the yard areas alone  (without including drip line samples) warrant remedial
action (i.e., excavation and removal).

       The eight properties selected for resampling had among the highest soil lead
concentrations found at any of the Study Group properties.  It is well known that drip line
areas tend to have higher lead levels than general yard soil because lead-bearing particles
deposited on roofs,  as well as paint flakes tend to accumulate in these areas.  Therefore it is
not surprising that drip line areas are significant contributors to overall yard soil lead at
some of these properties.  However, the lead levels in the general yard soil at the properties
sampled on the Site were still high enough to be of concern even if drip line areas are
disregarded.  When all 100 Study Group properties are considered, the average lead concentration
in the drip line areas was only about 40% higher than the average level in front yard and
backyard areas.  A similar pattern was seen for the Reference Area properties.  Lead in drip
-------
line areas certainly contributes to the lead levels in yard soil as a whole,  but it cannot be
considered the major or predominant source.

       b.      Sample Depth

       E&E used a sample depth of 0 to 1 inch to estimate lead concentrations in surface soil
that young children are likely to contact while playing,  and that children are likely to ingest
via hand-to-mouth contact, and that are likely to be tracked into the house and become house
dust.  D&M used a sample depth of 0 to 2 inches in its study.  The EPA's risk assessment
guidance manual notes in discussing sample depths that assessment of surface exposures will be
more certain if samples are collected from the shallowest depth that can be practically
obtained.   Given the exposure pathways of interest (i.e., soil tracked into the home and soil
which is ingested during hand-to-mouth contact) the soil tracked into the home and/or handled by
a young child is more likely to come from the upper 1 inch of soil than to come from the upper 2
inches; therefore, the 0 to 1 inch sample depth is more appropriate for the exposure pathways
under consideration.

       c.      Differences in XRF Analytical Techniques

       D&M argues that the Metorex 920 XRF spectrophotometer used in the D&M study is superior to
the Spectrace 6000 XRF spectrophotometer used by E&E and that the Spectrace results above 1,000
mg/kg probably suffer from a gross lack of precision.

       About 550 different samples from all of the sampling areas of the 100  Study Group
properties were analyzed by both XRF spectrophotometry, using the Spectrace 6000,  and by ICP
using the standard EPA Contract Laboratory methods.  The XRF and CLP results for these samples
were compared using linear regression analysis.  The regression of the lead concentrations
measured by XRF on those measured by CLP was highly significant  (p<0.0005), the slope of the
regression line was 1.08 with a standard error of 0.03.  The correlation coefficient was 0.86
and the r-2 was 0.74 indicating that 74% of the variance in the XRF values was accounted for by
the CLP values.  A scatterplot showed that the relationship between the XRF and CLP values was
linear up to at least 4,000 mg/kg. Comparison of the scatterplot of the Spectrace versus CLP
results obtained by E&E to the Metorex versus CLP results reported by D&M in its Residential
Yard Assessment Report for Jasper and Cherokee Counties shows that the Spectrace results were at
least as linear and precise as the Metorex results obtained with their Model 5 soil shown in
Figures 5 and 6, the best of the three model soils used.

       Based on the comparison between the XRF and CLP results,  EPA Region VI is satisfied that
the Spectrace results are reliable and rejects assertions to the contrary.

       d.      Lead in Chat

       D&M argues that the lead concentration in chat is  not high enough to account for the lead
levels observed in residential soil at the Site Study Area.

       Many of D&M's arguments involve extrapolation of findings from the Jasper and Cherokee
County studies, which may not apply to the Site which is in Ottawa County.  According to D&M,
CCJM sampled 4 of about 25 chat piles in Picher and found an average lead concentration of 838
mg/kg.  D&M notes, in support of its argument, that the concentrations in two of these piles
were below 400 mg/kg.  However this means that the other two piles must have had lead
concentrations that averaged more than 1,200 mg/kg, concentrations that could account for the
lead concentrations found in most of the residential soil.  Furthermore, D&M noted the presence
of chat in a substantial number of the soil samples it collected during its resampling efforts.
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       e.      Lead in Smelter Emissions

       D&M suggests that the lead in soil from Study Group properties in Picher might have come
from a smelter source based on findings from areas of Jasper and Cherokee Counties  (Jasper and
Cherokee Counties are not part of the Site) where smelters operated.

       As  noted in the D&M report,  there was no known smelting activity in Picher.  The Ontario
Smelting Company smelter  (later purchased by Eagle-Picher) is the only smelter known to have
operated on the Site and it is located in the southeast part of the Hockerville area, about 3
miles east of Picher.  The Ontario Smelting Company smelter was much smaller than the smelter
located in Joplin, and it operated for only about 15 years.  The smelting in Joplin continued
for approximately 90 years.  Investigation of the smelter in Joplin showed that the prevailing
wind in the Tri-State Mining District is from the northwest and carries plumes mainly to the
southeast.  Elevated soil lead concentrations were detectable only up to 2 1/4 miles from the
Joplin smelter.  The Ontario Smelting Company smelter is located 3 miles east of Picher in a
generally downwind or cross-wind direction.  Therefore, at that distance, and in that direction,
it is unlikely that emissions from the Ontario smelter could be responsible for the soil lead
concentrations found in Picher.

       Moreover,  D&M bases its suggestion,  that the lead found in Picher was from a smelter
source, in part on certain samples submitted to Dr. Burke Burkart for X-ray diffraction analysis
described in the D&M report.  Dr. Burkart presented speciation results of ten samples in a July
1995 report (Burkart, July 6, 1995)   (the "first report") and the results of another ten samples
in a September 1995 report  (Burkart, September 23, 1995)  (the "second report").  However,  the
conclusions in the two Burkart reports, regarding a smelter source, are not consistent with some
of the data presented in the reports, with the common observation of mining waste in yards at
the Site,  and also with historical information about the Site.  In the first report, failure to
observe galena (PbS) and sphalerite  (ZnS) was a basis for concluding that "furnace products" and
not "mine tailings" were the source of the lead and zinc in the samples.  However, in the second
report, upon reexamination of these same samples  (the first ten samples), sphalerite was
positively identified.  Also, another investigator (Drexler, 1996) identified the presence of
galena in soil from the Site.  Since, according to Burkart, sulfide minerals  (e.g., galena) at
the Site would be expected to convert to oxidized phases, it is not suprising that little galena
was found in the soil.  Also, in the first Burkart report, chemical compounds that are know to
be weathering products of ZnS and PbS that were present in the samples were apparently not
recognized as possible indicators of a mine tailings source.  This oversight was partially
corrected in the second report as sulfide ores were recognizeds a source of oxidized lead and
zinc phases.  Also, in the first Burkart report, furnace products were attributed to a "zinc
metallurgical furnace," although no zinc smelters are known to have operated at the Site.   The
zinc oxide commonly observed in the samples was attributed to smelters in the first report.
However, the second report explains that zinc oxide is a weathering product of sphalerite.
Sphalerite was one of the two main minerals mined at the Site.  The other main mineral that was
mined was galena.  The first report identified chert particles with ZnO coating and the second
report identified ZnO present on the same sample grains with ZnS.  Both of these observations
are descriptive of weathered sphalerite.  Weathering products of galena and weathering products
of sphalerite, both in association with silicious chert fragments of the type commonly observed
at the Site, are indicative of a chat source.  The oxides of lead at the Site are likely the
oxidized phases of sulfide minerals and products formed insitu in the soil of oxidized phases of
sulfide minerals and various metals present in the soil.  In the first report, the fine grained
guartz fraction present in all of the samples was attributed to "furnace processes." In the
second report, chat was identified as the "most likely origin" of the fine grained guartz
fraction present in the samples, reversing the earlier conclusion that the fine grained guartz
was from furnaces.  In the second report, guartz, most likely from chat according to Burkart,
was the primary component of the fine fraction.  Light colored chert fragments were commonly
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observed in the coarse grained fraction of the samples.  Light colored siliceous    chert
fragments are commonly observed to dominate the coarse fraction in chat samples at the Site.
Chat is a source for the type of chert fragments observed in the samples.  The second report
concluded that the transported products, as distinct from a natural soil material, appeared to
be mill tailings and smelter products.  Based on these considerations, EPA believes that
Burkart's conclusion that mill tailings are indicated as a source of the samples is consistent
with the overall Site data.  However, EPA guestions the conclusion indicating the smelter
products are a source, as this is inconsistent with the overall Site data.  The EPA believes
that the steam furnaces associated with many of the mines and mills at the Site, are more likely
to be a source of the slag-like and furnace like products observed in the samples than smelters.
This belief is based upon historical information that steam furnaces used to power mining
machinery were common in Picher, whereas only one smelter (which was small compared to smelters
in Joplin, Missouri and Galena, Kansas) has been positively identified and it was located three
miles east of Picher in a crosswind or downwind direction.  For the reasons discussed above, the
results of the Burkart reports, indicating that smelter products are a source is considered
inconclusive by EPA.

       f.      Lead in House Paint

       D&M argues that lead-based paint is a source of lead in soil in Picher.  D&M notes that
E&E found lead-based paint at a number of homes in Picher and that paint chips were observed in
many drip line samples and some other soil samples.  However, D&M makes no specific claim and
offers no opinion as to the relative importance of lead paint as a source of the lead in soil.

       The EPA has acknowledged the presence of lead-based paint at a number of residences both
in Picher and in Afton, the Reference Area.  The EPA has discussed the lead paint data in detail
in responses to earlier comments (see e.g., 1, 4, 20, 21, 33, 36, and 47).  Paint chips have
been found in a number of soil samples, and lead-based paint may be an important source of lead
in soil at some residences; however, EPA believes that the weight of evidence indicates that
lead-based paint is not the primary source of the elevated lead levels found at the majority of
residential properties in Picher.

       g.      Lead in Automobile Emissions

       D&M notes that automobile emissions are a well known historic source of lead in soil,
particularly near roadways, and observes that some of the lead in soil near highly traveled
roads in Picher could come from this source.

       The EPA acknowledges that automobile emissions were a historic source of lead released to
the environment and may have contributed, to a degree, to the lead found in yard soil in Picher.
Automobile emissions were also similarly a possible source in Afton, the reference area, where
the lead in yard soils is at a level where less than 1% of the   children are predicted  (using
the IEUBK lead model) to have elevated blood lead levels.  Automobile emissions cannot account
for the large differences in soil lead levels found between Picher and Afton, the reference are.
Also, the speciation results (Burkart, July 6, 1995, Burkart, September 23, 1995, and Drexler,
1996) did not indicate automobile emissions as a source of lead.
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                         Attachment 2 to Section II, Part B of Responsiveness Summary

                                           TAR CREEK SUPERFUND SITE
                                           TECHNICAL REPLY DOCUMENT
                                      RESIDENTIAL AREA RESPONSE ACTIONS
                                            (Revised July 10,  1996)

       This document is the U.S. Environmental Protection Agency's (EPA's)  reply to technical
comments in Gary D. Uphoff's letter of January 25,  1996, on behalf of ASARCO Inc., Blue Tee
Corporation, Childress Royalty Company,  Inc., Gold Fields Mining Corporation, NL Industries,
Inc., and The Doe Run Resources Corporation  (the "Companies") responding to EPA's Special Notice
of November 17, 1995, for the remedial investigation, feasibility study,  and remedial design
(RI/FS/RD)  for the residential areas at the Tar Creek Superfund Site  (the "Site"), Ottawa
County, Oklahoma.  This document also responds to additional technical comments from the
Companies  (with the exception of NL, Industries, Inc.) contained in Gary D. Uphoff's letter of
May 21, 1996.  Technical comments were also received in a letter of January 26, 1996, from
Suzanne R.  Schaeffer of the U.S. Department of the Interior  (DOI)  responding to EPA's Special
Notice of November 17, 1995.  EPA's responses to the technical comments received from the
Companies and from DOI have been combined into this single Technical Reply Document because the
issues raised by both DOI and the Companies are similar  (hereinafter the Companies and DOI are
referred to collectively as the Respondents).  The documents EPA relied upon in preparing this
technical reply include the following:

Draft Baseline Human Health Risk Assessmert Report,  Tar Creek Superfund Site, Ottawa
County, Oklahoma, Prepared for EPA by Ecology and Environment, Inc.,  December 1995

Risk Assessment Guidance for Superfund:  Volume 1 - Human Health Evaluation Manual,
Part A, OSWER, EPA, 1989

Supplemental Region VI Risk Assessment Guidance, EPA Region VI Draft Document, May
5, 1995

Revised Interim Soil Lead Guidance For CERCLA Sites and RCRA Corrective Action
Facilities, OSWER Directive No. 9355.4-12, EPA, July 14, 1994

Guidance Manual for the Integrated Exposure Uptake Biokinetic Model For Lead In
Children, OERR Publication No. 9285.7-15-1, EPA, February 1994

In the following analysis of the Respondents' comments, the following terms are used as
indicated below:

       •    Study area - means the mining area of Ottawa County which was the subject of the
            Baseline Human Health Risk Assessment (BHHRA);

       •    Study group - means the 100 homes in Picher where multi-media environmental samples
            were taken;

       •    Reference area - means the 15 homes in Afton, Oklahoma which are outside of the
            mining area where multi-media environmental samples were taken; these homes were used
            for comparison to homes within the mining area;

            OSDH survey - means the Oklahoma State Department of Health (OSDH) Picher blood lead
            survey unless the OSDH county-wide survey is specifically referenced.
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EPA'S REPLY TO GENERAL COMMENTS

1.     The Respondents,  focusing on the county-wide results from the OSDH blood lead survey,
       noted that 5.6% (13 of 232)  of the Ottawa County children tested had blood lead levels
       exceeding lOlg/dL.   The Respondents state that even these results may be biased high
       because they include the results from the door-to-door survey in Picher.  The Respondents
       have also expressed that additional bias is introduced by not using the latest results
       from followup retesting.  The Respondents suggest that EPA use the county-wide results,
       rather than the results for Picher, as a basis for its decision-making regarding the
       remediation of lead contamination at the Site.  In response,  EPA would like to make the
       following points:

       a.      The OSDH county-wide statistics cited by the Respondents are not representative of
              blood lead  levels in the mining areas of Ottawa County (the mining areas make up  the
              Site);  therefore, county-wide results are not important to EPA's decision-making
              regarding remediation of lead contamination at the Site.   The OSDH county-wide  blood
              lead survey was not conducted in a manner likely to produce statistically
              representative results.   While the OSDH Picher results were based on a systematic
              door-to-door sampling effort,  the county-wide results  for areas  outside of Picher
              were based  on a self-selected sample of walk-in participants.  The Respondents'
              description of the results of the OSDH county-wide blood lead survey is also
              potentially misleading,  because the freguency,  cited by the Respondents,  of blood
              lead levels  greater than or egual to 10 Ig/dl is for all of the  children in the
              survey.   This includes children of all ages,  not just  children 6 years old and
              under,  who  are most likely to have elevated blood lead levels because of their
              natural propensity to engage in hand-to-mouth behavior,  and who  are most sensitive
              to the  effects of lead.   Also,  over one-third of the 232 children tested in the OSDH
              county-wide  survey were residents of communities outside of the  mining area,  where
              lead-contaminated soils and mining wastes are not prevalent.  EPA believes it is
              more pertinent to focus on results within the mining area,  which is the subject of
              EPA's response action.  The OSDH survey found that the proportion of young children
              with elevated (10 Ig/dL or greater)  blood lead levels  in Picher  was substantially
              greater than outside the mining area.  That finding suggests that there is a
              positive relationship between blood lead levels and exposure to  mining-related
              contamination,  and that blood lead levels within the mining areas of Ottawa County
              are likely  to be higher than in the county as a whole.

       b.      The OSDH blood lead results for Picher are most relevant for comparison to the
              results of  the Baseline Human Health Risk Assessment (BHHRA), because the Picher
              survey  was  conducted within the same geographical area as EPA's  study group (100
              homes in Picher)  investigation.  That is,  the Picher survey was  conducted in an area
              where mining waste is prevalent,  whereas the county-wide OSDH survey includes areas
              where mining waste are not prevalent.  The Picher blood lead survey found that  21%
              of the  young children tested had blood lead levels of  10 Ig/dL or greater.  These
              results are  consistent with the predictions of the Integrated Exposure Uptake
              Biokinetic  (IEUBK)  model in the BHHRA,  which were based on lead  concentrations  found
              in environmental media (i.e.,  non-paint media such as  soil,  house dust,  tap water,
              and air)  at  the study group homes.

       c.      It is well  know that lead exposure prevention education and increasing awareness
              about lead  poisoning can produce a reduction in observed blood lead levels.
              Children who test high initially often retest lower, as reported by OSDH for some of
              the children at the Site,  due to improved hygiene and  other exposure reduction
              activities  resulting from lead exposure prevention education and greater awareness
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              about  lead poisoning.

       d.      EPA does  not  use  blood  lead data  alone  as  a  basis  for  remediation  decisions.
              Reliable  blood lead data  is difficult to obtain, and interpretation  of  the  results
              is  also often difficult because of  confounding  factors such  as  small sample sizes.
              Accordingly,  no blood lead survey can serve  as  the sole basis for  EPA's decision
              about  whether a particular release  of lead warrants a  response.  EPA will respond
              when it makes a finding that there  has  been  a release  of lead to the environment,
              and that  the  release may  pose a threat  to  human health or welfare  or the
              environment.

       e.      EPA uses  national surveys of blood  lead levels, e.g.,  the National Health and
              Nutrition Examination Surveys (NHANES), for  information purposes.  However,  EPA does
              not determine whether or  not a response action  is  warranted  at  a given  site by
              making comparisons to average blood lead levels obtained from national  surveys  such
              as  NHANES III.  EPA believes that it is more meaningful,  in  evaluating  the
              significance  of blood lead results  from communities within the  Site,  to make
              comparisons with  blood  lead results from other  similar communities within the
              Tri-State area, but outside of the  mining  district.

       f.      EPA currently relies on the predictions of the  IEUBK lead model to evaluate the
              potential risks.   Generally,  EPA's  policy  is to attempt to limit environmental  lead
              levels so that a  typical  child or group of children will have an estimated  risk of
              no  more than  5% of exceeding the  10 Ig/dL  blood lead level.  EPA hopes  to address
              releases  of lead  before the lead  causes elevated blood lead  levels in children.

2.      The Respondents  assert that the  area-wide  residential  soils in the  mining area have fairly
       uniform concentrations of lead;  therefore, a uniform increase in blood lead levels of
       children in the  mining area would be expected, rather  than the type of distribution
       actually observed in the OSDH  survey. However, it  is  not EPA's observation that the lead
       concentrations in soil in the  study area are uniform.  In fact,  there  is  considerable
       variability in the lead  concentration in soil  in  the study area as  documented  in the
       BHHRA.   Figure E-l from  the BHHRA shows  the cumulative distribution of lead concentrations
       in soil in the study area as a whole, in soils from the study group homes,  and in  soils
       from reference area  homes. The  large range of lead concentrations  in  soil  samples from
       these areas illustrates  the degree of variability of lead levels in soils within these
       areas.   There is also variability in an  individuals' exposure to the lead in soils due to
       differences in activity  patterns among individuals. Therefore,  EPA sees  no reason why a
       uniform increase in  blood lead levels should necessarily  be expected if lead in soils  was
       the major  source of  lead exposure for a  population.

3.      The Respondents  assert that EPA's planned  soil removal actions are  inconsistent with and
       unwarranted by the CDC guidelines contained in the  October 1991 CDC publication,
       "Preventing Lead Poisoning in  Young Children"  (the  "CDC guidelines").  The  Respondents
       suggest that  since the blood lead levels in the area children, according  to the OSDH blood
       lead survey,  are found primarily in the  10-14  Ig/dL range, that the response,  based on the
       CDC guidelines in Table  1-1 of Chapter 1 and the  "Interpretation of Blood Lead Levels"
       Section of Chapter 4,  should be  limited  to health education and follow-up blood lead
       testing.   However, the Respondents,  charge that EPA is inconsistent with  the CDC
       guidelines overlooks the recommendation  for community-wide childhood lead poisoning
       prevention activities made in  Table 1-1  and focuses primarily only  on  Chapter  4 which
       describes  the role of pediatric  health-care providers. The guidelines in Chapter  4 are
       not targeted  to  the  role of environmental  programs  like Superfund in addressing the
       environmental sources of lead  in communities to prevent blood lead  poisoning.   Chapter 4
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       provides guidance to pediatric health-care providers in response to documented blood lead
       levels,  i.e.,  a case management approach.   However,  if properly interpreted the CDC
       guidelines do not advise against the planned response actions proposed at the Site which
       are designed to address the environmental  sources of the elevated blood leads in the
       community, but on the contrary, the CDC guidelines lend support to EPA's planned response
       actions.  Even at the 10-14 Ig/dL range,  community-wide childhood lead poisoning
       prevention activities are recommended by the CDC guidelines (see Table 1-1,  Chapter 1)
       when many children are in this range.  Based on the OSDH blood lead survey for Picher,
       many children, 21 percent,  had elevated blood lead levels;  this definitely triggers
       community-level intervention according to  the CDC guidelines.   Chapter 9 of the CDC
       guidelines explains that (i)n theory, primary prevention has always been the goal of
       childhood lead poisoning prevention programs.  In practice, however,  most program focus
       exclusively on secondary prevention, dealing with children who have already been poisoned.
       As programs shift the emphasis to primary  prevention, their effort must be designed to
       systematically identify and remediate environmental sources of lead,  including, most
       importantly, dwellings containing old lead paint.

       The shift from case management to community-level intervention will reguire a fundamental
       shift in perspective.  The focus must shift from the individual child to the population of
       children at risk and the environment in which they live.  The purpose of community-level
       intervention is to identify and respond to sources,  not cases, of lead poisoning.

       From the foregoing excerpts from the CDC guidelines, it is clear that a community-level
intervention, as planned for the Site, is the preferred approach rather than the secondary
prevention, case management, approach that the Respondents recommend.  It is also clear from the
CDC guidelines that primary prevention activities that identify and remediate environmental
sources of lead before the lead causes elevated blood lead levels in children are preferred.
EPA'S RESPONSE TO THE COMPANIES' COMMENTS ON THE BHHRA

[Note: This section of the Technical Reply Document attempts to respond point-by-point to the
issues raised in the Dames & Moore comments enclosed with Gary D. Uphoff's January 25, 1996,
letter.  There is some redundancy in the responses because of overlap in some of the issues
raised.]

EPA's Responses to Dames & Moore's General Comments:

       The objective of the Tar Creek BHHRA was to evaluate potential risks associated with
environmental site-related contamination (lead and other metals)  at residential properties.  The
risk assessment was structured to address that guestion as directly and unambiguously as
possible.

       The risk assessment conforms to current EPA risk assessment guidance.   Accordingly,
potential health risks from lead were assessed using EPA's IEUBK model.  As pointed out in the
Companies' comments, it is well known that exposure to lead-based paint is a major source of
elevated blood lead levels in young children.  Inclusion of exposure of lead in paint chips in
the IEUBK model has a major impact on the blood lead levels predicted by the model, overwhelming
the contributions from all other sources.  EPA was interested in determining whether
environmental media alone, without the contribution of lead from lead-based paint, posed a
health threat to children on the Site.  Therefore, exposure to lead in paint chips was excluded
from the BHHRA in order to focus on  (1)  exposures to lead in environmental media at residential
properties (the bulk of these environmental-media lead exposures was likely to be due to
site-related contamination), and (2) the potential impact of exposure to environmental
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 (non-paint) lead on blood lead levels in children).

       The IEUBK model was used as an indicator of the range of blood lead levels in children
that could result from exposure to the lead concentrations measured in environmental media at
the study group residences.  The BHHRA report clearly explains that a number of default exposure
assumptions (based on national averages or observations at other sites)  were used, and that
those assumptions may differ from actual exposures.

       The EPA investigation of residential areas of the Tar Creek Site  focused on a detailed
investigation of environmental contamination and relied on standard EPA risk assessment methods
to evaluate the potential risks posed by the contamination.  it did not  include any blood lead
sampling, partly because blood lead surveys were being conducted by other agencies  (Agency for
Toxic Substances and Disease Registrv (ATSDR),  OSDH, and the Indian Health Service  (IHS)).
Although those surveys provided useful information an blood lead levels  in the area, matched
environmental samples intended to measure lead in the environment in which the blood-sampling
participants lived were not collected.  Conseguently, those blood lead surveys cannot be used to
guantitatively evaluate relationships between lead in environmental media at area residences and
blood lead levels.  It should be noted that the OSDH data was not released to EPA until after
the BHHRA had largely been completed.  A summary of the results of the OSDH blood lead survey
was included in the BHHRA, because the results could be considered evidence of a possible effect
of environmental site-related contamination on human health.  The OSDH survey, which shows a
high percentage of children with elevated blood lead levels living in Picher is certainly
consistent with the BHHRA's finding that environmental lead from mining  waste poses a high risk
to human health.  The similarity between the percentage of young children found to have blood
lead levels of 10 Ig/dL or greater and the percentage predicted by the IEUBK model was noted,
but this was neither intended nor represented as validation of the model.

       The blood lead levels measured in the children 72 months of age and younger in the OSDH
survey are not directly comparable to the blood lead levels predicted by the IEUBK model for at
least two reasons.  First, the children included in the OSDH survey were not randomly selected
from the population of Picher, and their exposure levels were not measured; thus, there is no
way of knowing whether the homes of the children in the OSDH survey are  comparable, as a group,
to the 100 randomly selected study group homes that served as the basis  of the blood lead levels
predicted by the IEUBK model.  Second, the blood lead levels predicted by the IEUBK model
reflect only exposure to lead in environmental media plus lead in the diet, whereas the measured
blood lead levels necessarily reflect all of the lead exposures experienced by these children,
including exposure to lead-based paint chips, if any.  If the homes of the children included in
the OSDH survey were reasonably comparable to the BHHRA study group residences, the measured
blood lead levels would be expected to be higher than the levels predicted by the IEUBK model if
lead paint chips were a significant source of lead exposure for these children.  Since the
measured levels were not higher, it is unlikely, assuming reasonable comparability between OSDH
survey homes and BHHRA study group homes, that lead in paint chips is the primary source of lead
exposure for these children.

       The BHHRA report makes no statement about the factors that may be responsible for the
observed elevated blood lead levels at the Tar Creek Site; it reports the possible sources
suggested in studies it summarizes, but makes no statement of its own.  The report does state
that elevated blood lead levels predicted in the study group are due primarily to elevated
levels of lead found in outdoor soil and indoor dust because soil and dust accounted for most of
the total lead uptake estimated by the IEUBK model.   To the extent that  mining waste materials
contribute to the elevated lead concentrations in soil and dust, they would also contribute to
total lead uptake.  The BHHRA explained that ingestion of lead-based paint chips, which could be
a major source of lead exposure for some children,  was excluded from the guantitative evaluation
for the reasons discussed above.  Even excluding possible paint chip ingestion, the IEUBK model
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predicts that blood lead levels of children living in the study group homes could be
unacceptably high due to lead in environmental media, notably soil.  Predicted blood lead levels
would be even higher if there were additional exposures from ingestion of paint chips.  The
possible impact of lead paint chips on blood lead levels is discussed in the uncertainty section
of the risk characterization (Section 5.4.1), immediately following the risk characterization
summary in the BHHRA report.

       The Companies claim that EPA in the absence of any analytical or observational data to
demonstrate, or even suggest, any real human health risks attributable to metals in yard soils,
prepared a modeled risk assessment to support a preconception by EPA concerning systematic human
health risk associated with mining wastes.  This is not true.  EPA did suspect that
mining-related wastes were a major source of environmental contamination (i.e., non-paint
contamination) in the study area (the mining area identified in Figure 1-1 of the BHHRA).   This
suspicion was appropriate, however, because the presence of large amounts of mining-related
waste in the study area, and the contamination of groundwater and surface water by mine-derived
contaminants were the reasons the area was originally listed as a Superfund site.  Also,  a blood
lead study conducted for the Region 7, Jasper County portion of the Tri-State mining district,
had indicated that blood lead levels were significantly higher in the exposed group within the
mining area compared to the control group outside the mining area.  These Region 7 studies also
indicated that exposure to soil was the most important factor influencing the distribution of
blood lead levels between the two groups.  Due to similarities between the Region 7 and Region 6
portions of the Tri-State mining district, it was reasonable to suspect that similar problems
related to mining waste might exist in both portions of the Tri-State mining district.  The
BHHRA describes the Site history, the occurrence and releases of potential source materials
(mining wastes) in the area,  and the potential exposure pathways that exist, in accordance with
EPA risk assessment guidance.  However, no assumptions were made about the source(s) of
environmental contamination in preparing the guantitative risk evaluations for lead or any of
the other chemicals of potential concern  (COPC).  For COPCs other than lead, observed
concentrations in environmental media were used to calculate exposure point concentrations in
accordance with the EPA guidance cited in the BHHRA.  Likewise, for lead, observed
concentrations or averages of the observed concentrations of lead in soil,  house dust, and tap
water from each individual study group and reference area (area of the 15 homes in Afton)
residence were used directly as inputs to the IEUBK model.  Mining wastes are responsible for
the estimated risks and predicted blood lead distributions to the extent that they contribute to
elevated contaminant concentrations in environmental media.   As discussed earlier,  lead in paint
chips was omitted from the IEUBK model to determine whether the lead levels in environmental
media alone were sufficient to result in blood lead levels high enogh to be of concern, which
was one of the main objectives of the BHHRA.

       The Companies suggest  that mining wastes are not the primary source of potential lead
exposure; however, data collected during the extensive investigation of the Tar Creek Site
indicate otherwise.  Cadmium, lead, and zinc are the elements primarily associated with area
mining wastes.  Elevated levels of cadmium, lead, and zinc serve as a signature for the presence
of mining waste in environmental media from the area.  The site investigation showed that the
concentrations of cadmium, lead, and zinc in soil from the study group homes were approximately
10 times greater than the concentrations of cadmium, lead, and zinc in soil from the reference'
area homes.  The site investigation also showed that these elements had the greatest elevation
of any of the metals measured.   In addition, lead concentrations in soil from the study group
homes exhibit highly significant (p <0.001) positive correlations with the cadmium and zinc
concentrations in the soil.  The foregoing evidence indicates that mining waste is the major
source of lead in outdoor soils in the Tar Creek area.

       It is possible that lead in paint could contribute to the lead concentrations in soil and
dust.  However, if lead in paint were a significant contributor to the concentrations of lead in
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soil and dust, one would expect the lead levels in soil to be disproportionately elevated
compared to the cadmium and zinc concentration levels in soils,  but lead concentrations in areas
subject to paint contamination are proportionate to the concentrations of cadmium and zinc.
That is, where lead is highly concentrated in soil, zinc and cadmium are also typically highly
concentrated in soil.  Since zinc and cadmium concentrations cannot be attributable to paint
contamination, but can be attributed to mining waste, it can be concluded that the high
concentrations of lead, proportionate to the cadmium and zinc concentrations, are due primarily
to mining waste and not to paint.  Outdoor paint chips were collected from 52 of 100 study group
homes and 4 of 15 reference area homes; indoor paint chips were obtained from 10 study group
homes and 1 reference area home.  All of the paint chips were analyzed for lead.  The small
number of samples from reference area homes makes a detailed comparison of the prevalence of
lead paint at homes in the two areas difficult; however, the available data do not indicate a
marked difference between the two areas.  Using a level of 5,000 mg/kg (i.e,  0.5% which is the
standard for lead in paint used by the U.S. Department of Housing and Urban Development (HUD)
and some state regulations) as an indicator of the presence of lead paint, the percentages of
homes found with lead paint in the study group and in the reference area were roughly the same.
Outdoor lead paint was found at 24 of the 52 study group homes sampled and at 3 of the 4
reference area homes sampled, indicating the presence of lead paint at 24% (24 of 100)  of the
study group homes and 20%  (3 of 15) of the reference area homes.  The mean lead concentration
reported in outdoor paint samples from the study group was lower than in the reference area.
Fewer indoor paint samples were collected and the lead concentrations were generally lower than
the lead concentrations in outdoor paint; the indoor paint lead concentrations exceeded 5,000
mg/kg in just one of the 10 study group homes sampled.  Only one indoor paint sample was
collected from a reference area home.  Its lead concentration (2,600 mg/kg),  which was below the
criterion for lead paint, was similar to the mean concentration found in paint from the study
group homes.  Overall the data suggest that the prevalence of lead paint and, therefore, the
potential exposures of children to lead from this source are probably no greater in the study
group than in the reference areas homes.  Also, specifically for outdoor soil, since the
available data provide no evidence that the prevalence of lead paint differs significantly
between the study group and reference area homes, the possible presence of lead paint in the
soil is not likely to account for a significant part of the (order of magnitude) difference in
soil lead concentrations measured between the study group and the reference area homes.

       House dust and yard soil were estimated by the IEUBK model to account for more than 80% of
the environmental lead exposure to young children in the study group homes.  Fifty of the 100
study group homes had average dust lead concentrations greater than 200 mg/kg.  The dust lead
level of 200 mg/kg is an upper-end estimate for background dust concentrations and is the IEUBK
model default level for dust.  Only five of these 50 homes had higher lead concentrations in
dust than in soil, which would suggest another significant source of lead.  That is, the fact
that most homes had higher concentrations of lead in soil than in dust would suggest that inside
paint was not the cause of unusually high levels of lead in dust in the home.

       To summarize,  the information bearing on the possible sources of lead exposure in the Tar
Creek area is as follows:

       •    Elevated levels of cadmium, lead, and zinc is a indicator of tht presence of mining
            waste in the Tar Creek area;

       •    The median and average concentrations of cadmium,  lead, and zinc were each
            approximately an order of magnitude higher in soils from study group residences than
            in soils from reference area residences, indicating that mining waste is the major
            source of elevated lead concentrations, which are proportionate to cadmium and zinc,
            in study group soils;
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       •    Lead paint was found in approximately the same proportion of study group and
            reference area homes, indicating that the presence of lead paint is not likely to
            account for a significant part of the difference in soil lead concentrations between
            the homes in the two areas, and;

       •    Fifty of the 100 study group homes had average lead concentrations in house dust
            greater than 200 mg/kg, which could be considered elevated.  Only five also had dust
            concentrations higher than the corresponding soil concentrations, suggesting the
            probable presence of a significant source of lead other than the outdoor soil in only
            5 of the fifty homes.

       Overall,  the evidence indicates that mining waste is the major source of elevated lead
levels in environmental media in the Tar Creek area,  and therefore it is likely to be the major
contributor to lead exposure in the area.  Lead paint may be present at some residences and
could contribute to the lead concentrations in soil and house dust at those residences, but it
can not account for the major differences in lead concentrations between the study area and
reference areas.  Lead paint may contribute to lead exposures at some homes and could be a major
source of lead exposure at those homes; however,  lead paint does not appear to account for a
major portion of the lead in soil or house dust in the Tar Creek study area.

       Apparently,  the main evidence the Companies use to support their hypothesis that lead
paint, rather than mining waste, is the primary source of lead exposure in the area is the
similarity between the blood lead levels measured in the OSDH survey (which necessarily reflects
all sources of lead exposure, including any exposure to lead paint)  and the blood lead levels
predicted by the IEUBK model, which excluded exposure to lead paint.  The Companies apparently
assume that the measured blood lead levels include a substantial exposure to lead paint because
numerous studies have shown that exposure to lead paint can have a major effect on blood lead
levels.  Since the blood lead levels measured in the OSDH survey, which must reflect any
exposure of these children to lead paint that may have occurred, are similar to the blood lead
levels predicted by the IEUBK model, which excluded paint exposure,  the Companies apparently
conclude that the IEUBK model must have overestimated lead exposure from environmental sources.
As noted above,  the sets of residences underlying the blood lead levels measured in the OSDH
survey and those used in obtaining the IEUBK model predictions may not be comparable; however,
if they are, it is probable that the predicted and observed blood lead levels are similar
because lead paint is not a major contributor to lead exposures in the Tar Creek area.  That is,
only five of the 50 homes in the study group which had average lead concentrations in house dust
greater than 200 mg/kg also had dust concentrations higher than the corresponding soil
concentrations,  suggesting the probable presence of a significant source of lead other than the
outdoor soil.  Moreover, even if lead paint is identified as a significant source of
contamination at a residence, it does not necessarily mean that lead paint is actually the major
source of exposure at that residence.

       The Companies also note that interior and exterior lead-based paint was identified as a
source of lead contamination in the ATSDR lead exposure investigation in the Fall 1994.  The
ATSDR lead exposure investigations was a followup investigation to the finding that 35 percent
of the Indian children that had been tested by the IHS had elevated blood lead levels.  [As a
side note, some of the children with elevated blood lead levels sampled by the IHS lived outside
the mining area.  However, it is not unusual that elevated blood lead levels existed in towns in
Ottawa County distant from the mining area, since such towns may have other industrial sources
of lead.  Also,  mine waste materials have been transported from the mining area to other areas
for use as driveway material, playground material, and for other uses for which gravel is
typically used.]  However, ATSDR only identified significant sources of lead in two of the nine
houses sampled.   For these two houses, the lead was attributed to lead-based paint.  For the
other houses, significant sources of lead were not identified.  That does not mean that
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significant sources of lead did not exist.  The ATSDR exposure investigation did not conclude
that the elevated blood lead levels were not from mining waste.  At several of the houses,
investigators reported that mine tailings material was used for the driveways.  ATSDR's soil
samples were a composite of normal soil material and also mine tailings,  if present.  ATSDR did
not use separate composites of each of the areas of a yard and types of material to the extent
that EPA did in its investigations.  The concentration of lead in mine tailings is typically
much higher than normal soil materials, based on sampling results from Region 6 and Region 7.
It is likely that the type of sample compositing that ATSDR conducted diluted the typically
higher concentrations for mine tailings.  Even with the type of compositing that ATSDR
conducted, samples of soil from four of the houses had lead concentration greater that EPA's 400
mg/kg soil lead screening level (see EPA Revised Interim Soil Lead Guidance for CERCLA Sites and
RCRA Corrective Action Facilities, July 14, 1994).

EPA's Responses to Dames & Moore's Specific Comments:

Lead in Soils, Minus 60 Mesh

       The Companies criticized the approach used by EPA for estimating the exposure
concentration of lead in soil at each residence by simply averaging the lead concentrations
found in the front yard, back yard, play area, dripline (the point where runoff from the roof
hits the yard), and driveway samples.  EPA believes this averaging approach is valid.  While the
assumption that a child's exposure would be divided egually among these sources is unprovable,
as the Companies say, any alternate assumption is egually unprovable.  EPA considered the use of
a weighted average of concentrations measured in five areas in each yard.  Under the weighted
average approach, the averages would be weighted to reflect the amount of time a young child
might spend in each area; however, this approach was rejected because  (1) without site-specific
data, any weighting scheme would be subjective and subject to dispute, and (2) any reasonable
weighted average is likely to be numerically similar (+ or - 10 to 20%) to the simple average,
therefore, the use of a weighted average is not likely to have a substantial effect on the
outcome of the risk assessment.  Averaging the soil concentrations is the simplest and most
reasonable approach for estimating long-term exposure in the absence of site-specific
information to the contrary.  The uncertainty associated with this assumption is recognized and
discussed in Section 3.5.6 of the BHHRA report.

       The Companies commented that garden soil metal concentrations should be included in the
outdoor soil average.  However, the BHHRA clearly explains that garden soil data were not
included in the outdoor soil average because small children normally would not be expected to
spend much time in a garden.  That is, allowing children to play in a garden on a regular basis
is likely to be incompatible with successful gardening because of the physical damage to plants
that is likely to occur.  Therefore, it was assumed that parents who wish to raise a garden
will take steps to prevent or minimize this behavior.  This is consistent with the way other
contaminant exposures were assessed in the BHHRA.   Under the BHHRA, only adult residents were
assumed to engage in gardening activities involving contact with garden soils.

       The Companies criticized EPA's determination of lead concentrations based on the
minus-60-mesh fraction only.  However, the soil samples were prepared in accordance with EPA
Region 6's standard procedures.  For the Contract Laboratory Program  (CLP) analyses, that
included sieving the samples through a 60-mesh screen.   The minus-60-mesh fraction includes
particles approximately 250 microns in size or smaller and is the fraction most likely to adhere
to the skin and be ingested through hand-to-mouth contact.  The EPA lead work group recommends
that lead concentrations measured in this fraction of soil be used in the IEUBK model.

       The Companies contend that the results of the CLP analyses of only the minus-60-mesh
portions of the soil samples overstate  (bias upward) the actual lead concentrations in the soil
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by two or three times.  The Companies contend that the minus-60-mesh portion constitutes only a
small percentage of the sample by weight and that metals are concentrated in this finer
material.  However, the Companies present no site-specific evidence to support this premise.
Most of the samples collected from the study group homes were not chat, but soil or soil mixed
with chat.  The Companies refer to grain size tests from other Superfund sites indicating that
the percentage of minus-60-mesh material in chat may be only 12 to 15%.  However, the percentage
of minus-60-mesh material in soil samples from the study area was generally much higher.  Sieve
analyses indicate at least two thirds of most samples and over 80% of many samples would pass
through a 60-mesh sieve (estimates were derived from the 40- and 100-mesh sieves since no
60-mesh results were reported in the sieve analyses).  The Companies use XRF measurements of
lead in chat driveways in Cherokee County, Kansas, and Jasper County, Missouri, from another
study to estimate the bias of the CLP results for chat driveway samples from Picher.  However,
such an estimate of bias is questionable.  In addition to differences in sampling and analysis
methods, there may be real differences in the lead content of the chat between the samples from
Picher and samples from Cherokee County and Jasper County.  [Incidentally,  page 5-9 of the BHHRA
report does not state that the mean lead concentrations for chat are similar throughout the
District, as the Companies suggest,  but only that "the minerals extracted and the mining and
milling process used were largely the same."]  Furthermore, it is not reasonable to extend this
estimate of bias to soil samples.

       As mentioned in the previous  paragraph,  the Companies contend that using only the
minus-60-mesh portions of the soil samples biases the actual lead concentrations in the soil
upward by two or three times.  However, a comparison of the results of the CLP and XRF analyses
of cadmium and lead in study group soil samples, in Appendix E of the BHHRA report, shows that
no such bias exists.  Appendix E states that the Wilcoxon test for matched pairs "showed that
the CLP and XRF results for lead were significantly different at the 0.05 level, but that
cadmium results were not statistically different."  The fact that there was no statistical
difference between the cadmium data from the CLP analysis of the minus-60-mesh fractions of the
soil samples and the XRF analysis of the minus-10-mesh fraction shows that cadmium is not
substantially more concentrated in the finer of these two fractions.  In addition, although the
lead results by CLP and XRF analyses were significantly different in a statistical sense, the
difference was small.  The mean difference between the XRF and CLP results for the same sample
(XRF - CLP)  was -1.5 mg/kg, or less than 1%; the median difference was +21.9 mg/kg, about 4%,
which indicates that the CLP results were more often lower, not higher, than the XRF results.
The regression equation describing the overall relationship between the CLP and XRF lead results
also indicates that they were quite similar.  Based on the equation, XRF lead concentrations of
100, 500, and 2,000 mg/kg are equivalent to CLP lead concentrations of 109, 500, and 1,864
mg/kg.  The regression equation also indicates that,  at higher lead concentrations, the CLP
results were slightly lower, not higher, than the XRF results.

Lead in Dust, Inhalation Pathway

       The Companies suggest that the site-specific value for the lead concentration in air
should be used in the IEUBK model rather than the model default value.  However, the use of the
IEUBK model default value for the lead concentration in air, rather than a lower estimate based
on the local air measurements (which averaged between one-fifth and one-third of the default
value), had virtually no effect on the IEUBK model results because the inhalation route
accounted for less than it of the estimated total lead uptake.

Lead in Paint as a Source

       The Companies commented that  the BHHRA ignores lead-based paint as a source and made no
effort to discriminate between mining waste lead and paint lead.  EPA realizes that both mining
waste lead and outdoor paint lead are possible sources of lead in soil at the Tar Creek Site.
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However, the BRHRA indicates that paint lead is not the major source.  While paint lead was
found at some of the residences, it was equally prevalent in the study group and the reference
area homes.  Since there is little difference between the prevalence of lead paint between the
study group and the reference area and since lead from automobile emissions is not expected to
be significantly different between the study group and the reference area,  then another source
of lead, other than paint lead or automobile exhaust lead, is needed to explain why the lead in
the soil at the study group homes was approximately 10 times greater than the lead in the soil
at the reference area homes.  This difference between the lead in the soil between the study
group and the reference area is explained by the widespread presence of mining waste in the
study area.  As mentioned earlier, elevated levels of cadmium, lead, and zinc serve as a
signature for the presence of mining waste in environmental media from the area.  The site
investigation showed that the concentrations of cadmium, lead, and zinc in soil from the study
group homes were approximately 10 times greater than the concentrations of cadmium, lead, and
zinc in soil from the reference area homes.  The presence of elevated levels of other
mining-related contaminants (notably cadmium and zinc) in addition to lead in soils at the
majority of study group homes, and the absence of elevated levels of such contaminants in soils
in the reference area homes, indicates that mining waste is the major source of lead in outdoor
soils.  Note that the BHHRA mentions the use of chat as fill or surfacing material, in addition
to fugitive dust (past and current emissions) from chat piles and flotation ponds, as a source
of site-related contamination.

       As for lead in indoor dust, the degree of correlation between soil and dust lead
concentrations and the presence of higher dust lead concentrations in some homes clearly shows
that there may be other sources of lead in house dust, including paint.  The risk
characterization acknowledges, in Section 5.1.2.1, that outdoor soil is not the principal source
of the highest observed indoor dust lead concentrations and mentions paint as a possible source.
It should be noted, however, that in a substantial majority of study group homes with average
soil lead concentration exceeding 1,000 mg/kg (26 of 30), the dust lead levels were elevated
above 200 mg/kg.  The dust lead Level of 200 mg/kg is an upper-end estimate for background dust
concentrations and is the IEUBK model default level for dust.  This indicates that lead
contamination in outdoor soil is probably a significant contributor to lead in indoor dust at
the study group homes.

       The Companies suggest that the BHHRA implies that the transport of lead via fugitive dust
from neighboring chat piles is the primary contributor to outdoor lead contamination.  Nowhere
in the BHHRA report was it implied that fugitive dust was the primary contributor to outdoor
lead contamination.

IEUBX Model 0.99 and Lead-Based Paint

       The Companies suggests  that,  when the IEUBK model was used,  the multiple source option for
dust should have been used for some homes where the indoor dust lead concentrations were greater
than the outdoor soil lead concentrations.  The Companies suggest the use of the multiple source
option to separate the contribution of outdoor soil from the contributions of other sources,
including paint, to total lead in dust.  However, it is unclear exactly how and why this should
be done.  The multiple source option for dust is intended to be used when household dust lead
data has not been collected.  It allows the IEUBK model user to estimate household dust lead
concentrations based on contributions from soil, air, and (if selected) various alternate
sources, including several nonresidential sources and lead-based paint.  Certainly, it is
possible to "back out" estimates of the relative contributions of soil and paint to lead in
house dust, if the concentrations of lead in all of these media are known.   However, as noted by
the Companies, the results are highly sensitive to the values assumed for the coefficients that
describe the relationship between the concentration of lead in household dust and concentrations
in the other media.  What coefficient value would be assumed for soil, which is indicated to be
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the greatest contributor of site-related lead? Regression analysis of the soil and dust data
from the study group homes showed a positive correlation between soil and dust lead
concentrations.  However, the default soil-to-dust coefficient used by the IEUBK model (0.7)
appears to be too high; the "site-specific" value based on the data for the study group homes
was 0.26.  Additionally, there are other important determinants of lead concentrations in house
dust that are not accounted for by the multiple source option  (e.g.,  housekeeping practices).
Given the uncertainties, no purpose would be served by this exercise other than to show that
paint may be a major source of lead in those households where dust lead levels were greater than
soil lead levels, something that is already stated in the BHHRA report.

       The Companies criticize the BHHRA for not including the available paint data in the
guantitative evaluation of lead.  According to the IEUBK model guidance manual, the correct use
of the IEUBK model is to estimate geometric mean blood lead levels and distributions of blood
lead levels in young children who have long-term chronic exposures to lead."  The IEUBK model
guidance manual goes on to explain that ingestion of paint chips on even a single occasion can
cause serious lead intoxication, and states that "(t)he IEUBK model is not intended to address
this situation.  While the model allows for the evaluation of paint chip ingestion (in addition
to lead-based paint present in household dust),  the IEUBK model guidance manual cautions against
such an evaluation, iting the great uncertainties in estimating chronic exposure by this route,
and makes no recommendations for exposure parameter values.  Because the huge uncertainty and
the likely overwhelming effect that inclusion of paint data would have had on the IEUBK model
results, a decision was made to set the paint data aside and to discuss the implications in the
uncertainty section.  The objective of the BHHRA was to evaluate potential health risks from
environmental site-related contamination, not from lead-based paint.   The possibility of
additional exposures to lead from ingestion of paint does not reduce the potential risks posed
by environmental site-related lead contamination.

       The reasons for omitting the paint chip data and the potential impact of paint chip
ingestion on blood lead levels were discussed in the BHHRA report.  The suggestion that the
paint chip data was deleted to force-fit the model prediction to the observed blood lead levels
(presumably the OSDH blood lead results from Picher) has no basis in fact.  The OSDR blood lead
results had not been released and were unavailable to EPA when most of the BHHRA was prepared
from September through November 1995.  The Picher data (Table 5-3, copied from a table in the
OSDH memo) was added to the BHHRA when it became available.  [The source listed at the bottom of
the Table 5-3 is incorrect, but will be corrected in the revised BHHRA report.]  In presenting
the Picher data, the BHHRA report states that 21% of children age 6 and under had blood lead
levels greater than or egual to 10 Ig/dL, and that the percentage is similar to the percentages
that were predicted by the IEUBK model.  However, there is no implication that the observed
blood lead concentrations confirm the model predictions,  nor is there any attempt to explain Lht
blood lead levels in terms of the model predictions.

       The OSDH memo provides no information on known or likely sources of lead exposure for the
individuals who exhibited elevated blood lead levels, and lead-based paint is certainly one
possible source.  However, the relatively greater number of young children found to have blood
lead levels of 10 Ig/dL or more in Picher  (10 out of 48 tested, or 21%) versus other parts of
Ottawa County  (4 out of 105 tested, or 4%) suggests that there is a connection with
mining-related contamination.

       The Companies stated that the results of the lead speciation tests should be provided in
the BHHRA.  However, the results of the lead speciation analysis were inconclusive and could not
be used to determine the sources of lead in study area soils.  As noted above, the coexistence
of elevated concentrations of cadmium, zinc, and other mining-related contaminants with lead in
study group soils indicates that mining waste is the main source.
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IEUBK Model Validation

       The Companies'  comments regarding the IEUBK model validation are full of misleading
statements.  Section 5.4.1.2 in the BHHRA is a general discussion of the validity of the IEUBK
model and is largely based on information presented in the IEUBK model guidance manual.  The
main point of that discussion is that while the model and its default values have been refined
using matched environmental and blood lead data from a number of other sites, validation of the
model by comparison with empirical data is an ongoing process.  Nevertheless, the results so far
have been satisfactory, according to the manual.

       The available blood lead results mentioned in the Companies'  comment regarding IEUBK model
validation are obviously those released by OSDH in its memo dated December 18, 1995.  The OSDU
blood lead data cannot be used in any way to validate the IEUBK model or to justify changes in
the model default values because the OSDH survey was not designed for that purpose and,
conseguently, lacks critical information needed if it were to be used for that purpose.  Because
the OSDH sampling was not conducted according to a statistically based sampling plan, the OSDH
blood lead data cannot be considered representative of the general population of children in
Picher and Ottawa counties.  Sampling was most obviously biased outside of Picher, where
participants were limited to children whose parents or guardians were aware of the blood lead
screening program and were willing and able to transport them to one of the testing site's at
local community centers.  Because of this bias, the mean blood lead level and geometric standard
deviation  (GSD)  from the OSDH data are not reliable.  In addition, because no matched
environmental samples were collected along with the blood lead samples, the environmental lead
exposures of the children in the OSDH blood lead survey are unknown.  Note again that the final
statement in Section 5.1.4 of the BHHRA report is merely an observation about the Picher blood
lead data, not a validation statement about the IEUBK model.

       The Companies state that no attempt appeared to be made,  in the BHHRA, to calculate an
Ottawa County specific geometric GSD.  However, although the IEUBK model guidance manual
provides a procedure for calculating the GSD (in "Appendix A:  How to Calculate the Geometric
Standard Deviation from Blood Lead Data, If You Must"),  it discourages the user from changing
the default GSD in the model to a site-specific value, even when data from a well-conducted
study are available.  The IEUBK model guidance manual states, "(u)nless there are great
differences in child behavior and lead biokinetics among different sites, the GSD values should
be similar at all sites, and site-specific values should not be needed."  Furthermore, a
site-specific GSD cannot be calculated in accordance with the methods in Appendix A, because a
site-specific GSD requires, in addition to the blood lead data,  information that is not provided
in the OSDH survey, including soil lead levels and dust lead levels.   [Incidentally, if the
Appendix A procedures are ignored and all of the data is treated as if it were from a single
homogeneous group, which it is not, the GSD of the OSDH blood lead data for Picher children 6
years of age or less is 2.1, which is greater than the model default of 1.6.  So even this rough
approximation produces a higher GSD value.]

       The Companies suggested that the IEUBK model be checked by utilizing matched blood lead
data and environmental lead data.  Although, matched blood lead data and environmental lead
data, if available, could be used to check the IEUBK model predictions, such a comparison
probably would not lead to any conclusive statement about the model's validity.  The model
should not be expected to reproduce observed blood lead concentrations exactly.  As long as the
prediction interval includes the observed blood lead level corresponding to the same exposure
inputs, the model's performance is considered satisfactory.  Even when the predicted and
observed levels do not overlap, there may be a plausible explanation that does not necessarily
invalidate the model.

Fugitive Dust Contamination of Yards
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       The Companies criticized the approach used in Section 6 of the BHHRA to calculate
increases in lead concentrations in yard soils from air deposition.  Section 6 was included at
the end of the BHHRA to address EPA's concern that possible recontamination of remediated areas
by redeposition of fugitive dust from chat piles or other sources might frustrate efforts to
remediate residential properties.  Even using extremely conservative assumptions that are likely
to overestimate actual redeposition rates, Section 6 concludes that recontamination of the soil
via deposition of airborne particles is a slow process and would not be expected to lead to
significant recontamination.

       The BHHRA never suggested that dust from chat piles has been the primary contributor to
lead in yard soils, only that it was one of several sources of mining-related contamination,
including chat used as fill.

Afton as a Reference Site

       The Companies guestioned whether Afton constituted an appropriate reference or background
area for EPA's investigation.  However, Afton was selected as the reference site for EPA's Tar
Creek investigation precisely because it is one of the few communities in Ottawa County located
outside the mining district and away from any other obvious sources of metals contamination,
but it is similar to the study group in other respects such as such as type and age of housing
stock and demographics.  Based on site visits and visual observations, no socio-demographic
variables that are important to the BHHRA are know to be significantly different between the
study group and the reference area.  There are no areas within the mining district that can be
assumed to be uncontaminated by mining waste because mining activities were so widespread.  The
ore formation that was mined at the Site is over one hundred feet below the surface of the
ground and natural surface minerals cannot account for the much higher levels of cadmium, lead,
zinc, and other metals that were found in soils in Picher.  It is clear that these surface
minerals were deposited during mining activities.

       Afton was selected as a reference area for a study of environmental contamination, not
blood lead levels.  While differences in socio-demographic variables such as education levels,
income levels, and ethnicity may be very important factors to consider in blood lead studies,
because they may be related to behavioral patterns that could affect children's overall
exposures, the relevance of these variables to environmental contaminant levels is guestionable.
The suggestion that possible socio-demographic differences between the study group and reference
area homes invalidate all comparisons of environmental data from the two areas or predictions
based an that environmental data is not supported by any evidence.

Lead Concentrations, Indoor versus Outdoor

       The Companies stated that the correlation between indoor dust lead concentrations and
outdoor soil lead concentrations is very poor and implies that the outdoor concentrations may be
biased.  However, the Companies appear to have misunderstood the statistical summary information
provided.  The multiple R value for the regression, commonly called the correlation coefficient,
was 0.82; the r# value was 0.67.  This actually indicates that the regression was highly
significant and remarkably good, considering the variability inherent in environmental data.  In
this simple linear relationship, the concentrations of lead in soil account for 67% of the
variability in the lead concentrations in house dust.  The slope of the regression line was
0.26, indicating that the dust concentrations predicted by the regression would be 26% of the
corresponding soil concentration.

       This statistical relationship in no way implies any bias in the soil lead concentrations,
as the Companies suggest.  The comparison of CLP results  (on the minus-60-mesh portion) and XRF
results  (on the minus-10-mesh portion) for lead and cadmium clearly indicated that metals
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concentrations found in soil were not artificially elevated to any significant degree by sieving
the samples.  The outdoor soil results used in the dust/soil correlation analysis were averages
of individual samples results at each residence,  not the grand mean of five data sets, as
stated by the Companies.  Since fine material from all of the outdoor areas sampled are
potential sources of dust that could be tracked or blown into the home and contribute to indoor
dust,  it is entirely appropriate to combine these results.

Dames and Moore's Conclusions

       EPA has already responded above in detail  to the four points of criticism raised in the
conclusion of the Dames & Moore comments on the BHHRA; however, a summary response to the four
points is as follows:

       1)      The Companies  criticized the BHHRA  based on the fact that the blood lead data was
              not used for validating or calibrating the IEUBK model.   However,  as discussed
              above,  the empirical  blood lead data cannot be used for  validating or calibrating
              the IEUBK model,  because the OSDH survey was not designed for that purpose and,
              conseguently,  lacks critical information needed if it were to be used for that
              purpose;

       2)      The Companies  criticized that the lead paint chip data was excluded from the
              guantitative assessment.  As discussed above,  the BHHRA  clearly explained the
              reasons for excluding the paint chip data from the IEUBK model runs and discussed
              the possibility that  paint chip ingestion could be a major route of exposure for
              some children;

       3)      The Companies  guestioned the validity of using Afton as  the reference area because
              of  possible differences in socio-economic variables between the reference area homes
              and the study  group homes.  However,  as discussed above,  Afton was selected as the
              reference site  precisely because it is one of the few communities in Ottawa County
              located outside the mining district and away from any other obvious sources of
              metals  contamination.   Afton is similar to the study group in other respects such as
              such as type and age  of housing stock and demographics.   Based on site visits and
              visual  observations,  no socio-demographic variables that are important to the BHRRA
              are know to be  significantly different between Afton and the study group.   Even if
              such differences existed,  they would not invalidate the  comparisons of environmental
              data, which show that concentrations of cadmium,  lead, zinc,  and other
              mining-related  contaminants are substantially elevated in the study group; and

       4)      The Companies  stated that BHHRA used soil lead concentrations that were highly
              biased.  As discussed above,  this is not true.   Comparison of CLP and XRF results
              for study group soil  samples showed that the CLP results were not artificially
              elevated to any significant degree.

       It appears that the main thrust-of the Companies' comments was  to attempt to change the
focus of the BHHRA from an evaluation of the risks potentially posed by environmental
contamination (including lead and other site-related contaminants) at  the Tar Creek Site to a
recapitulation of the effects that lead paint can have on blood lead levels.  EPA acknowledges
that ingestion of lead paint chips can dramatically increase blood lead levels and that
inclusion of paint chip data in the IEUBK model can substantially raise the blood lead
distributions predicted by the model.  However, lead paint and the risk it can pose was not and
is not the focus of the site investigation carried out or the BHHRA.  The BHHRA shows that
even without considering the effect of paint chips, the lead-contaminated soil on the Site can
be expected to result in a risk to children of unacceptably high blood lead levels.
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       A review of the data collected in the site investigation indicates that:

       •    A number of contaminants (including lead) are present at substantially elevated
            concentrations in environmental media in the Tar Creek study area compared to the
            reference area;

       •    The combination of contaminants present, principally cadmium, lead,  and zinc, which
            are well known to be constituents of mining waste in the Tar Creek area,  indicates
            that mining waste is the major source of the environmental contamination;

       •    Exterior "lead-based paint", as defined by HUD (greater than 0.5%, or 5,000 mg/kg,
            lead), is present at 20 to 25% of the residences in both the study group and
            reference areas, indicating that lead paint is unlikely to contribute significantly
            to the great difference  (an order of magnitude difference) in lead concentrations in
            soii between the study group and reference areas;

       •    Of the 50 study group homes with lead concentrations in house dust that might be
            considered elevated (greater than 200 mg/kg) ,  only five (10% had dust concentrations
            higher than the corresponding soil concentrations, indicating that in most cases
            elevated house dust concentrations can be accounted for by the corresponding soil
            concentrations, and;

       •    While lead paint was found at some of the residences, it was egually prevalent in the
            study group and reference area homes, and there is no evidence that it is a major
            source of the lead in soil, or of the lead in dust in most homes.

       Based on the lead concentrations actually measured in soil,  house dust, and tap water,  the
IEUBK model predicts that about 20% of young children living in study group homes could have
blood lead levels greater than 10 Ig/dL.  Thus, the BHHRA concludes that exposure to lead in
environmental media alone could result in blood lead levels above EPA's target level.  Since
lead paint was found at some of the residences, some of the children might also be exposed to
lead paint.  That exposure would be in addition to potential exposure to lead in environmental
media, and if it were included in the IEUBK model would result in an even greater percentage of
children with predicted blood lead levels greater than 10 Ig/dL.

EPA'S RESPONSE TO DOI'S COMMENTS

       [Note:  Much of the DOI letter of January 26,  1996,  dealswith non-technical issues, outside
of the BHHRA,  that have been addressed in other correspondence.  Almost all of the issues raised
by DOI have been addressed in the above responses to the Companies, and many of the responses
below are excerpted/repeated from those responses.  This section of the Technical Reply Document
responds only to comments about the BHHRA on pages 2 and 3 of the DOI letter.]

       DOI states that EPA's draft risk assessment fails to demonstrate that mining waste is the
source of those elevated blood lead levels that exist at the Site.   However, that was not its
objective.  The objective of the BHHRA was to evaluate the potential risks associated with
environmental site-related contamination, not to explain observed blood lead levels.   What the
BHHRA did indicate, using EPA's IEUBK model, was that exposure to the elevated concentrations of
lead in soil and dust that are present in many study group homes could lead to unacceptably high
blood lead levels in children.  To the extent that mining wastes contribute to the elevated
concentrations of lead in soil and dust, they would also contribute to total lead uptake and
blood lead levels.  The BHHRA did not suggest that there are no other sources of lead in soil
and dust or that there were no other routes of lead exposure.  In fact, the document mentions
that lead-based paint may be a source of lead in household dust  (Section 5.1.2.1) and that
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ingestion of paint chips could be a major route of lead exposure in some homes (Section
5.4.1.1).  These issues, related to lead-based paint which appear to be DOI's primary basis for
asserting that the BHHRA is flawed, are discussed in detail in the responses  to the Companies'
comments.

       DOI stated that the BHHRA disregards paint as an explicit source of lead exposure and
concludes that nearly all of the exposure is due to soil and household dust exposure.  EPA
disagrees.  The BHHRA did not conclude that nearly all of the exposure is due to soil and
household dust exposure, as stated by DOI at the bottom of page 2.  Rather, the document states
that the elevated blood lead levels predicted in the BHHRA study group are due primarily to
elevated levels of lead found in soil and dust because soil and dust accounted for most of the
total lead uptake estimated by the IEUBK model.  The BHHRA report clearly explained that
ingestion of paint chips, which could be a major source of lead for some children, was excluded
from the guantitative evaluation.  While is true that flaking paint is a possible source of lead
in soil and dust, the presence of highly elevated concentrations of cadmium,  zinc, and other
mining-related contaminants in addition to lead in the soils at the majority  of study group
homes,  and the absence of such contamination in soils in the reference area,  indicate that
mining waste is the major source of the lead in outdoor soils.  With regard to indoor dust, only
five out of 50 study group homes with lead concentrations in indoor dust that could be
considered elevated had indoor dust lead levels higher than the levels in the corresponding
outdoor soils.  This indicates that for most residences the lead levels in indoor dust can be
accounted for by the levels in outdoor soil.  Other sources of lead, including lead paint, could
exist and could be contributing to the lead levels in indoor dust, which was  acknowledged in the
BHHRA.   However, in most cases, it is not necessary to include such sources to account for the
lead levels found in the indoor dust.

       DOI concluded,  by comparing blood lead levels predicted by the IEUBK model with observed
blood levels from OSDH's survey for the Picher area, that EPA's BHHRA was overly conservative
and overestimated exposure from soil and dust associated with mining waste.  Regarding the blood
lead results from the survey conducted by the OSDH, the BHHRA stated only that 21% of children
ages 6 and under in Picher had blood lead levels greater than or egual to 10  Ig/dL, and that the
percentage is similar to those that were predicted by the IEUBK model.  DOI correctly points out
that if paint ingestion was included in the IEUBK model, the predictions would be higher.  DOI
apparently assumes that the measured blood lead levels must include a substantial component of
exposure to lead paint because other studies have shown that exposure to lead paint can have a
major effect on blood lead levels.  Apparently, since the blood lead levels measured in the OSDH
survey, which must reflect any exposure of these children to lead paint that  may have occurred,
are similar to the blood lead levels predicted by the IEUBK model, while excluding paint
exposure, DOI concludes that the IEUBK model must be overestimating lead exposure from
environmental sources.  DOI apparently has failed to consider the possibility that, while lead
paint exposure can be a major contributor to blood lead levels, it may not be a major factor at
the Site.  The sets of residences underlying the blood lead levels measured in the OSDH survey
and those used in obtaining the IEUBK model predictions may not be comparable because of
differences in the way the sample sets were obtained.  However, if they are comparable, it is
possible that the predicted and observed blood lead levels are similar because lead paint is not
a major contributor to lead exposures in the Tar Creek area.

       DOI stated that the use of the 30 percent bioavailability default assumption in the IEUBK
model runs was overly conservative and ignores recent research.  Findings from research
conducted by EPA Region 8 indicates that lead in yard soil and milling waste  samples taken from
the Tri-state mining area have a bioavailability of 30% or greater—the same  or higher than the
IEUBK model default.  In any case, the BHHRA (Section 3.5.6) acknowledged that IEUBK model would
tend to overestimate the uptake of lead and the resulting blood lead levels if the actual
bioavailability were lower than the model default value.  However, the OSDH blood lead survey
-------
was not conducted according to a statistically based sampling plan,  and the data are not
statistically representative.  Furthermore, the environmental lead levels in the homes of the
children in the blood lead survey are unknown and may be different from the EPA' s study group
homes.  No conclusions can be drawn from comparison of the OSDH blood lead data and IEUBK model
predictions in the BHHRA, except to say that the observed blood lead levels are consistent with,
the model's predictions.

       DOI criticized the BHHRA for failing to analyze the sources of lead causing the elevations
in children's blood lead levels.  However,  the OSDH blood lead survey provided no information on
environmental lead levels or environmental lead exposures that could be used to analyze the
sources of reported elevations in children's blood lead levels.  Such an analysis would have
reguired further investigation and was outside the scope of the BHHRA.  Note again that the
BHHRA's objective was to estimate potential risks posed by environmental site-related
contamination (not just lead) based on the results of the EPA's environmental investigation, not
to explain the results of blood lead surveys conducted by other agencies.  The OSDH blood lead
results were included in the BHHRA only as additional information that should be considered when
making risk management decisions.  The OSDH survey showed that blood lead levels of young
children in Picher are elevated above levels that are considered acceptable under Centers for
Disease Control  (CDC) or EPA lead management policies.  The BHHRA did not demonstrate that the
source of these reported elevated blood lead levels was exposure to mining wastes.  However, the
BHHRA did show that exposures to elevated concentrations of lead in soil and dust at many Picher
homes, which have been attributed primarily to mining wastes, could contribute significantly to
lead intake and might result in elevated blood lead levels.  Once again, all the BHHRA says is
that the OSDH findings were consistent with BHHRA predictions.
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                                                  APPENDIX B

                                       STATE OF OKLAHOMA. COMMENT LETTER


Dear Mr. Knudson:

The Oklahoma Department of Environmental Quality  (DEQ) would like to express our concurrence
with the U.S. Environmental Protection Agency's (EPA) Proposed Plan for Operable Unit 2 at the
Tri-State Mining site in Ottawa County, Oklahoma.   As part of this concurrence, the DEQ agrees
with EPA's site-specific residential soil clean-up level of 500 parts per million  (ppm) lead for
the Tri-State Mining site.

As you know, other large lead-contaminated sites,  primarily former smelters, are undergoing
remediation in Oklahoma.  The policy of the DEQ is to establish site-specific soil clean up
goals at these sites, based primarily on the bioavailability of the prevalent forms of lead
which are present.  These site-specific clean up remediation goals will provide protection
against the unacceptable risks of lead tposure to sensitive populations.

The predominant forms of lead at the Tri-State site are lead carbonates and lead oxides.  The
lead oxides and lead carbonates are natural weathering products of lead sulfides (i.e. galena)
which accounts for their presence at the Tri-State site.  These forms of lead are more soluble
and bioavailable than lead sulfides which usually dominate at smelter sites.

At the Tri-State Mining site, EPA estimated lead risks to children by using the Integrated
Exposure Uptake Biokinetic (IEUBK)  model.  IEUBK is designed to pharmacokinetically model
exposure from lead in water,  soil,  dust, diet, paint and other sources to predict blood lead
levels in the most sensitive population, which is children 6 months to 7 years old.  Using a
bioavailability of 30 percent, appropriate for the chemical forms of lead present at the site,
the IEUBK model predicted that 21 percent of children between the ages of 6 months and 7 years
living in Picher, Oklahoma (the community most impacted by mining waste) would have blood lead
levels above the Center for Disease Control's  (CDC) level of concern of 10 ug/dL.  This
prediction exceeded the CDC acceptable risk of no more than 5 percent of children between 6
months and 7 years of age having blood lead levels of 10 ug/dL or greater.

In addition, an independent blood lead survey conducted by the Oklahoma State Department of
Health  (OSDH) in October 1995 in Picher, Oklahoma found that 20.8 percent of young children in
the target age range had blood lead levels elevated to 10 ug/dL or greater.  This actual
measurement of lead in blood was very similar to the predicted levels for the same community.
The actual blood lead levels of children living in the Tri-State mining area are higher than any
other location in Oklahoma, including those communities with smelter sites.

In August and September of 1996, further independent blood lead surveys were conducted in Picher
and surrounding communities by the University of Oklahoma Health Sciences Center on behalf of
certain mining companies which once operated in the area.  These studies also indicated a high
percentage  (38 percent) of children in Picher with blood lead levels above 10 ug/dL.  The nearby
communities of Cardin and Quapaw also had elevated blood lead levels among a significant
percentage of children, 62 percent and 13 percent respectively.


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                                                  APPENDIX C

                                             I TEC COMMENT IiETTERS



April 8, 1997

Kent Curtis, Site Assessment Manager
Cherokee Nation
Office of Environmental Services
P.O. Box 948
Tahlequah, Oklahoma 74465
918-458-5498, FAX 918-458-5499

Bonn Walters, Community Involvement Coordinator
U.S. EPA, Region 6  (6SF-P)
1445 Ross Avenue
Dallas, Texas 75202-2733
214-665-6483, FAX 214-665-6660

Dear Mr. Walters:

On behalf of the Inter-Tribal Environmental Council  (ITEC),  which is a consortium of 31 tribes
in the state of Oklahoma and for which the Cherokee Nation's Office of Environmental Service
(OES) is the lead agency, I am submitting the following comments about the EPA's Proposed Plan
of Action for lead-contaminated soil at Residential Areas of the Tar Creek Superfund Site in
Ottawa County, Oklahoma.  This proposed plan of action impacts the population and lands of the
Quapaw, Ottawa, Peoria, Miami, and Wyandotte tribes, which are ITEC member tribes, and I have
asked representatives of these tribal governments to submit written comments to you concerning
the proposed plan of action.

The ITEC member tribes are in favor of the EPA's preferred remedial alternative 2 (soil
excavation with a 500 ppm action level).   However, it may not be possible for the EPA to obtain
access to all of the tribal members' properties that it wishes to remediate.  Therefore, at
least some of the community protective measures  (CPMs)  outlined in remedial alternative 3 will
probably have to be included in the remedial alternative that is selected for implementation.

One of the main reasons that tribal members may refuse to grant the EPA access to their
properties is that they are concerned that they will be held liable for cleanup costs on their
property.  If the EPA can assure all tribal property owners in writing that they will not be
held liable for cleanup costs, then access to nearly all properties will probably be granted.
If the EPA cannot give property owners such an assurance, then many owners may continue to
refuse access to their properties.  As remediation proceeds, many reluctant property owners may
eventually grant access to their properties after they see the results of remediation on their
neighbors' properties and note that their neighbors' are not being held liable for cleanup
costs.  Therefore, the EPA, the Bureau of Indian Affairs  (BIA) ,  and tribal governments should
make efforts to educate reluctant property owners about the benefits of remediation on their
neighbors' properties by hosting open houses and field trips to properties where remedial work
is in progress or has been completed.  Testimonials from owners of remediated properties should
also be included in these presentations.   Favorable opinions of the removal actions already
taking place in Picher, Oklahoma were voiced by residents and town council members of Picher at
the public comment meeting held by the EPA in Picher on March 27, 1997.  This is a success story
that the EPA, BIA, and tribal governments should publicize in order to promote the cooperation
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of reluctant property owners.

The EPA should conduct soil and sediment sampling in the Tar Creek floodplain in Miami, Oklahoma
to determine if flooding has contaminated soils on residential and other properties with lead
above the 500 ppm action level or with other metals above concentrations of concern.  If such
contamination proves to be a problem, then the EPA should evaluate the use of constructed
wetlands to control flooding and contaminant loading along the lower reaches of Tar Creek.  This
action should be included as part of the Record of Decision for the the Residential Portion of
the Tar Creek Superfund Site Operable Unit 2.

The Quapaw Tribe is interested in the possible economic development of two non-residential
properties that are located on tribal and individual trust lands in Cardin, Oklahoma.  These
properties are (1)  the former field office of the Eagle-Picher Mining Company, which is located
on Quapaw Tribal trust land in the 5/2, SW/4,  SE/4, Section 19, T29N, R23E, and (2) the former
Childress Chemical Company site (Cerclis no. OKD078641412),  which is located on individual
trust, land in the NW/4,  NE/4, Section 30, T29N, R23E.  Structural debris and lead-contaminated
soil are present on both of these properties.   In addition,  copper-contaminated soil is present
on the Childress site.  The Childress site has been referred to Gary Moore, who is the EPA's
On-Scene Coordinator for the Tar Creek Superfund site, for possible removal action.  ITEC urges
the EPA to proceed with removal or remediation of these two properties as soon as possible,
either as part of the Record of Decision for the Residential Portion of Operable Unit 2 or as
part of the fumare Record of Decision for the Non-Residential Portion of Operable Unit 2.
Timely remediation of these two properties will promote their economic development and thus
benefit the Quapaw Tribe.

Finally, ITEC wishes to know if any studies are being conducted, or will be conducted, to
document the nature of any lead-related health problems among residents of the Tar Creek
Superfund site.  Results of such studies, past and present,  should be made known to the public.



cc:    Noel Bennett,  Remedial  Project Manager,  U.S. EPA,  Region 6
       Robbie Hirt,  U.S.  EPA,  Region 6
       Monte Elder,  ODEQ
       John Gault,  Quapaw Tribe
       John Froman,  Peoria Tribe
       Margie Ross,  Ottawa Tribe
       Barbara Collier,  Wyandotte Tribe
       Tamra Bro,  Miami Tribe
       Dennis Sisco,  Bureau of Indian Affairs,  Miami,  Oklahoma
       File
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May 16,1997

Kent Curtis, Site Assessment Manager
Cherokee Nation
Offfice of Environment Services
P.O. Box 948
Tahlequah,  Oklahoma 74465
918-458-5498, FAX 918-458-5499

Bonn Walters, Community Involvement Coordinator
U.S. EPA, Region 6  (6SF-P)
1445 Ross Avenue
Dallas, Texas 75202-2733
214-665-6483, FAX 214-665-6660

Dear Mr. Walters:

On behalf of the Inter-Tribal Environmental Council  (ITEC),  I am submitting the following
comments as a supplement to my comments of April 8, 1997 concerning the EPA's Proposed Plan
of Action for lead-contaminated soil at Residential Areas of the Tar Creek SuperfiLnd Site in
Ottawa County, Oklahoma.  This proposed plan of action impacts the population and lands of the
Quapaw, Ottawa,  Peoria, Miami, and Wyandotte tribes, which are ITEC member tribes.

I have discussed the problem of obtaining access to tribal members' properties for the purpose
of remediation with Scott Thompson of the Oklahoma Department of Environmental Quality (ODEQ).
I agree with Scott that the EPA will continue to have trouble obtaining access to these
properties unless it implements one or both of the following options as part of the remedial
action:  (1) assure property owners in writing that they will not be held liable for the costs of
cleaning up their property; (2) offer property owners settlement agreements that would protect
them from efforts by the EPA and potentially responsible parties to recover cleanup costs.



cc:    Noel Bennett, Remedial  Project Manager,  U.S. EPA,  Region 6
       Robbie Hirt,  U.S. EPA,  Region 6
       Monte Elder,  ODEQ
       Scott Thompson,  ODEQ
       John Gault,  Quapaw Tribe
       John Froman,  Peoria Tribe
       Margie Ross,  Ottawa Tribe
       Barbara Collier, Wyandotte Tribe
       Tamra Bro, Miami Tribe
       Dennis Sisco, Bureau of Indian Affairs,  Miami, Oklahoma
       File
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                                                  APPENDIX D

                                         QUAPAW TRIBE COMMENT IiETTER



Dear Mr. Walters:

       This letter is to state the Quapaw Tribe of Oklahoma's opinion on the proposed action to
remediate the Tar Creek Superfund Site.  It is closely related to the one sent in by Kent Curtis
of the Inter-Tribal Environmental Council.

       The Tribe concurs that Remedial Action #2  is the  most appropriate.   The action level of
500 ppm is acceptable to the tribal leadership.  The major problem is access to Indian Country.
The Quapoaw tribe is most concerned that the EPA will not put into a contract that it will never
try to recoup costs of remediation from the land owners  or heirs.  Noel Bennet has stated that
this is policy but not written.  This will not mollify those that are skeptical of government
actions.  The EPA must put a clause in its remediation contracts that the costs will never be
borne by the allottees or their heirs.  Without this guarantee then the Tribe will be unable to
advise its members to allow the remediation.

       The Tribe is concerned about the plood plain of Tar Creek as well.   It is of our opinion
that those properties which are subject to flooding by Tar Creek be tested and allowed to fall
under the Tar Creek Superfund Remediation.

       The CHAMP program which published its findings last night at a dinner in Picher had lots
of pertinent data.  The Tribe feels that this data should become a part of the public record
regarding Tar Creek.  Much of the data is confidential,  especially that which pertains to
specific people and homes.  However, the conclusions and overall findings which identify no
particular individuals should be added to the Tar Creek  literature.  If not added then at least
mentioned so that later research will be so informed.

       Let me add that as the contact person for  the Quapaw Tribe that I am eager to resolve any
of the problems associated with the federal agencies and the status of Indian Country.  We do
not want to seem belligerent but we must look after not  only the health of the tribal members
but also their land holdings.


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                                                  APPENDIX E
                                        WYANDOTTE TRIBE COMMENT IiETTER

Environmental Protection Agency
Region 6
Community Relations  (6SF-P)
1445 Ross Avenue, Suite 1200
Dallas, Texas 75202-2733
Re:   Proposed Plan,  Tar Creek
     Super Fund Site
Dear Sirs:

Following review of your Tar Creek Proposed Plan of Action, and attending two of your community
meetings, I would agree Alternative 2 - Soil Excavation with 500 ppm Action Level is most
effective in order to maintain a cost effective remedy.  I feel this will create a much safer
environment especially for those living in the remains of the heavily mined areas.

Reiterating several verbal comments made during the community meetings I would again stress the
need for the Environmental Protection Agency to put forth the legal effort to agree to the
reguest of the Quapaw Tribe in placing a statement in the agreements for permission to excavate,
for those Native American land owners, there will be no monetary reguirements forced upon them,
at a later date.

As was stated by the Inter-Tribal Environmental Council member from the Cherokee Nation, Mr.
Kent Curtis, the lack of trust by the Native American land owners, does not stem from situations
dealing with the Environmental Protection Agency, however, broken promises and problems stemming
from broken treaties, and other numerous problems have been created throughout the years and the
trust is not going to be there unless good faith statements included in the agreements are
considered.

Personally, as a Quapaw-Tribal Member, I would like to see any and all of those individual land
owners improve their land, however, I do not blame them if they do not agree without the EPA,
and reguest written assurances.  Those of us who have been in Indian Business for several years,
of course, realize the Bureau of Indian Affairs is the entity that would be held responsible for
the improper handling of the closures of the mines and the mess that has been left behind due to
this fact.  We realized the individual land owners are not liable for what has transpired, as
they were at the mercy of the Bureau officials and their representatives to see that business
was professionally and properly handled.

It is my great concern, if this is not pursued and is not included in the agreements, many of
the Native American land owners will not agree to have their land excavated.  Essentially, then
will the Bureau of Indian Affairs be forced to cancel or not renew leases on lands and town lots
for those individuals that may have lived there for decades? It would be their responsibility
for those persons to live in a safe environment and unless excavated this would not be the case.
Without this agreement, I only see the federal government in a terrible situation, with no
solution in site.
Sincerely yours,

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                 APPENDIX F
         ADMINISTRATIVE RECORD INDEX
                 Prepared  for

United States Environmental Protection Agency

                   Region  6

         ADMINISTRATIVE RECORD INDEX

                     FOR

           TAR CREEK SUPERFUND  SITE
    (Operable Unit  2  for Residential Areas
             Record of Decision)

           EPA ID No. OKD980629844

                    ESS VI
        Work Assignment No. ESS06013

               Noel T. Bennett
           Remedial Project Manager
              U.S.  EPA Region 6

                 Prepared by

              DPRA Incorporated
            717 N.  Harwood Street
                 Suite 1300
             Dallas, Texas 75201

                 P.6113.06BE
               August 27,  1997
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                                                 INTRODUCTION

       The "administrative record" is the collection of documents which form the basis for the
U.S. Environmental Protection Agency's  (EPA) selection of a response action at a Superfund site.
Superfund is the name given to the Comprehensive Environmental Response, Compensation and
Liability Act (CERCLA) which can be found in Title 42 of the U.S. Code  (U.S.C.) at Sections 9601
through 9675.  As EPA decides what to do at the site of a release of hazardous substances, EPA
compiles documents concerning the site and EPA's decision into an "administrative record file."
This means that documents may be added to the administrative record file from time to time.
Once the EPA Regional Administrator or the Regional Administrator's delegatee signs the Record
of Decision memorializing the selection of the remedial action, the documents which form the
basis for the selection of the remedial action are known as the "administrative record."

       A remedial action is a type of CERCLA response action,  and EPA is taking a remedial action
at the Tar Creek Superfund Site  (the "Site") which includes most of Ottawa County, Oklahoma.
Under CERCLA section 113(k)  (which can be found in Title 42 of the U.S. Code at section 9613),
EPA must establish an administrative record for every CERCLA response action, and EPA must make
a copy of the administrative record available at or near the Site of the response action.

       The purpose of this document is to provide the public with an index to the administrative
record for EPA's remedial action decision at the residential areas on the site.  The
administrative record will be available for public review during normal business hours at the
EPA Region 6 offices which are located at the address given below, and it will also be available
at a repository  (e.g., a library) located near the site.

       The administrative record is treated as a non-circulating reference document.   Individuals
may photocopy any documents contained in the administrative record, according to the
photocopying procedures at the EPA Region 6 offices, and at the repository located near the
Site.

       The administrative record will be maintained at the local repository until at least the
end of the construction of the remedial action.  A public comment period was announced in the
Miami News-Record, a major local newspaper of general circulation.  The comment period lasted
from March 17, 1997, to May 23, 1997.

     The formal public comment period regarding this remedy selection is over, however, EPA
welcomes written comments at any time.  Please send all comments to:

                                         Mr. Noel T. Bennett (6SF-AP)
                                           Remedial Project Manager
                                 U.S.  Environmental  Protection  Agency  Region  6
                                               1445 Ross Avenue
                                           Dallas,  Texas 75202-2733
       This index and the record were generally compiled in accordance with the EPA's Final
Guidance on Administrative Records for Selecting CERCLA Response Actions, Office of Solid Waste
and Emergency Response (OSWER) Directive No. 9833.3A-1  (December 3, 1990).  According to OSWER
Directive No. 9833.3A-1,  Page 37, each Region should maintain a compendium of guidance documents
which are freguently used in selecting response actions, and the record located at or near the
Site should contain an index to the compendium of response selection guidance documents.
However, the EPA Headguarters-generated compendium of guidance documents has not been updated
since March 22,  1991 [see CERCLA Administrative Records:  First Update of the Compendium of
Documents Used for Selecting CERCLA Response Actions  (March 22, 1991)].  Moreover, the Region 6
-------
Superfund Division Director has decided that developing and maintaining a compendium index in
Region 6 would reguire extensive resources which are better utilized elsewhere in the Division.
Accordingly, the Division Director has decided not to maintain an indexed compendium of
response-selection guidance documents.  Instead, consistent with 40 CFR Sections 300.805(a) (2),
300.810(a) (2), and OSWER Directive No. 9833.3A-1, Page 37, the Region has listed, in the
Administrative Record Index, all guidance documents which may form abasis for the selection of
this response action.  Unless the guidance documents indexed were generated specifically for the
Site, the guidance documents may not be physically present in the administrative record.
However,  any guidance document listed in the index, but not physically present in the record
will be sent to the repository if a reguest is made to Mr. Bennett at the address indicated
above.  Copies of guidance documents can also be obtained by calling the RCRA/Superfund/Title 3
Hotline at 1-800-424-9346.

       Documents listed as bibliographic sources for other documents in the record might not be
listed separately in the Site index.  Where a document is listed in the Site index but not
located among the documents which EPA has made available to the repository, EPA will, upon
reguest,  include the document in the repository  (unless classified as a confidential document).

       The Administrative Record Index helps readers locate and retrieve documents in the record.
It also provides an overview of the response action history.  The index includes the following
information for each document:

       •     Administrative Record Page No. - The seguential numbers stamped on each page of the
            administrative record.  The six digit numbers are located in the upper right corner
            of each page.
       •     Document Date - The date the document was published and/or released.  "Undated" means
            no date was recorded.
       •     No. of Pages - Total number of printed pages in the document, including attachments.
       •     Author - Name and title of the originator.
       •     Company/Agency - Originator's affiliation.
       •     Recipient - Name, title, and affiliation of the recipient.
       •     Document Type - General identification, e.g., correspondence, Remedial Investigation
            Report, Record of Decision, etc.
       •     Document Title - Descriptive title or synopsis.

       Please note that all documents listed in the various administrative record indices which
are listed herein  (e.g., the Phase 1 Removal Index) are part of the administrative record for
this Record of Decision.
-------
                                          ADMINISTRATIVE RECORD INDEX
                                                     FINAL
SITE NAME:
SITE NUMBER:
  TAR CREEK SUPERFUND SITE
  OKD980629844
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
  000001  -  000563
  11/07/95
  563
  Unspecified
  U.S.  EPA  Region 6
  Public  and U.S. EPA Region 6 Site Files
  Administrative Record Index and Administrative Record
  Tar  Creek - Phase 1 Removal
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
  000564  -  000564
  04/08/96
  001
  Noel  T. Bennett,  Remedial Project Manager (RPM)
  U.S.  EPA  Region  6
  U.S.  EPA  Region  6 Superfund Site Files
  Memorandum
  Re:   04/08/96 phone conversation with Monty Elder,  Oklahoma Department of
Environmental Quality (ODEQ), about proposal to fill sinkholes at Commerce,
Oklahoma with old tires
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
000565 - 000565
05/15/96
001
Ghassan Khoury, Toxicologist, Superfund Branch
U.S. EPA Region 6
Noel T. Bennett, RPM, U.S. EPA Region 6
Memorandum
Review of draft soil cleanup utilizing demographic data for Jasper County
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
000566 - 001066
06/06/96
501
Unspecified
U.S. EPA Region 6
Public and U.S. EPA Region 6 Site Files
Addendum Index and Addendum Documents - Volume 1
Addendum to Removal Administrative Record  (AR) - Phase 1
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
001067 - 001451
06/06/96
385
Unspecified
U.S. EPA Region 6
Public and U.S. EPA Region 6 Site Files
Addendum Index and Addendum Documents - Volume 2
Addendum to Removal AR - Phase 1
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
001452 - 001452
06/21/96
001
Russell K. Holeman, Chief, Military/Environmental Branch
Corps of Engineers, Tulsa District
Noel T. Bennett, RPM, U.S. EPA Region 6
Cover Letter w/o Enclosure
Reguest for review and comment on Residential Remedial
Investigation  (RRI) Report
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
001453 - 001453
07/03/96
001
Russell K. Holeman, Chief, Military/Environmental Branch
Corps of Engineers, Tulsa District
Noel T. Bennett, RPM, U.S. EPA Region 6
Cover Letter w/o Enclosure
Reguest for review and comment on Draft Feasibility Study  (FS)
                                                                                   Report
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:

COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
001454 - 001456
07/10/96
003
Kent Curtis, Site Assessment Manager, Office of Environmental
Services
Cherokee Nation, Tahleguah, Oklahoma
Noel T. Bennett, RPM, U.S. EPA Region 6
Letter w/o Enclosure
Comments on Draft RRI Report
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
001457 - 001757
08/30/96
301
Ecology & Environment, Inc.
Contractor for U.S. EPA Region 6
Henry Thompson Jr., Project Officer, Program Management
Branch, U.S. EPA Region 6
Report
"Data Evaluation Summary Report, Site Assessment/Risk Assessment'
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
001758 - 002070
08/30/96
313
Ecology & Environment, Inc.
Contractor for U.S. EPA Region 6
U.S. EPA Region 6
Risk Assessment
"Baseline Human Health Risk Assessment of Residential Exposures"
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002071 - 002080
09/05/96
010
Unspecified
U.S. EPA Region 6
Public
AR Index
Removal Action, Addendum 2  (Documents indexed are incorporated
by reference into the Removal Action AR File.  Documents may be
reviewed at Region 6 or at the Miami Public Library, Miami, Oklahoma.
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002081 - 002081
09/19/96
001
Russell K. Holeman, Chief, Military/Environmental Branch
Corps of Engineers, Tulsa District
Noel T. Bennett, RPM, U.S. EPA Region 6
Cover Letter w/o Enclosure
Reguest for review and comment on Final Draft RI Report
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002082 - 002092
09/30/96
Oil
Unspecified
Ecology and Environment, Inc.
U.S. EPA Region 6
Report
"Preliminary Remediation Goals Residential Exposures"
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002093 - 002093
10/02/96
001
Russell K. Holeman, Chief, Military/Environmental Branch
Corps of Engineers, Tulsa District
Noel T. Bennett, RPM, U.S. EPA Region 6
Letter w/o Enclosure
Reguest for review and comment on Final Draft FS Report
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002094 - 002094
10/16/96
001
Robert Wilson
Corps of Engineers, Tulsa District
Noel T. Bennett, RPM, U.S. EPA Region 6
Memorandum
Review of RRI and RFS
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002095 - 002097
10/17/96
003
Kent Curtis, Site Assessment Manager, Office of Environmental Services
Cherokee Nation, Tahlequah, Oklahoma
Robert Wilson, U.S. Army Corps, of Engineers, Tulsa District
Letter
Comments on Final Draft "RFS Report"
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002098 - 002098
10/17/96
001
Russell K. Holeman, Chief, Military/Environmental Branch
Corps, of Engineers, Tulsa District
John Gault, Quapaw Tribe of Oklahoma
Letter w/o Enclosure
Final Draft RI and FS Reports
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:

COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002099 - 002100
10/18/96
002
Kent Curtis, Site Assessment Manager, Office of Environmental
Services
Cherokee Nation, Tahleguah, Oklahoma
John Gault, Quapaw Tribe of Oklahoma
Letter
Reguest for review and comment on RRI Report and RFS Report
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002101 - 002102
10/23/96
002
John Gault
Quapaw Tribe of Oklahoma
Noel T. Bennett, RPM, U.S. EPA Region 6
Letter
Comments on draft proposed plan
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
002103 - 002103
11/26/96
001
Noel T. Bennett, RPM
U.S. EPA Region 6
Scott A. Thompson, Environmental Program Director, Waste
Management Division, ODEQ
Letter w/o Enclosure
Reguest for review and comment on draft proposed plan for
remedial action for residential areas
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
002104 - 002104
11/26/96
001
Noel T. Bennett, RPM
U.S. EPA Region 6
Kent Curtis, Site Assessment Manager, Office of Environmental
Services, Cherokee Nation
Letter w/o Enclosure
Reguest for review and comment on draft proposed plan for
remedial action for residential areas
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:

COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002105 - 002105
12/05/96
001
Kent Curtis, Site Assessment Manager, Office of Environmental
Services
Cherokee Nation, Tahleguah, Oklahoma
Noel T. Bennett, RPM, U.S. EPA Region 6
Letter
Comments on draft proposed plan
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:

COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002106 - 002109
12/13/96
004
Deborah McNaughton, Senior Hydrologist, Waste Management
Division
ODEQ
Noel T. Bennett, RPM, U.S. EPA Region  6
Letter
Comments on draft proposed plan
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002110 - 002110
12/17/96
001
Gary Moore, On-Scene Coordinator
U.S. EPA Region 6
Noel T. Bennett, RPM, U.S. EPA Region 6
Memorandum
Costs of remedial site activities
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 002111 - 002115
12/18/96
005
Noel T. Bennett, RPM
U.S. EPA Region 6
Monty Elder, ODEQ
Facsimile Transmittal Cover Letter w/Enclosure
Re: Cost per residence for potentially responsible parties'
cleanup at the National Zinc site
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
 002116 - 002116
01/22/97
001
Noel T. Bennett, RPM
U.S. EPA Region 6
James Graves, Ottawa County Commissioner, District 1, Miami,
Oklahoma
Cover Letter w/o Enclosure
Request to review and comment on draft proposed plan for the
remedial action (long-term cleanup) for the residential areas
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:

RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 002117 - 002121
01/29/97
005
Unspecified
U.S. EPA, U.S. Department of the Interior  (DOI), and Bureau of
Indian Affairs  (BIA)
U.S. EPA Region 6 Superfund Site Files
Memorandum
Memorandum of Agreement among EPA, DOI, and BIA for future actions to  obtain
access to allotted Quapaw Indian lands to conduct response actions
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
002122 - 002336
02/03/97
215
Russell Holeman, Chief, Military/Environmental Branch
U.S. Army Corps of Engineers - Tulsa District
Noel Bennett, RPM, U.S. EPA Region 6
Cover Letter w/Report
RRI Report, Volume 1  (Prepared by Brown & Root Environmental)
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 002337 - 002787
02/03/97
451
Unspecified
U.S. Army Corps of Engineers, Tulsa District
U.S. EPA Region 6
Report
RRI Report, Volume 2  (Prepared by Brown & Root Environmental)
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 002788 - 002809
02/06/97
022
Unspecified
U.S. EPA Region 6
Public and U.S. EPA Region 6 Site Files
AR Index
Removal Action, Addendum 3 (Documents indexed are incorporated
by reference in the Removal Action AR File.  Documents may be
reviewed at Region 6 or at the Miami Public Library, Miami, Oklahoma.
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 002810 - 002830
02/07/97
021
Unspecified
ODEQ
U.S. EPA Region 6
Plan
Community Relations Plan

 002831  003073
02/11/97
243
Russell K. Holeman, Chief, Military/Environmental Branch
U.S. Corps of Engineers, Tulsa District
Noel Bennett, RPM, U.S. EPA Region 6
Report
RFS Report (Prepared by Brown & Root Environmental)

 003239 - 003239
02/21/97
001
Monty Elder,  Risk Communication Supervisor
ODEQ
Gary Moore, On-Scene Coordinator, Response and Prevention
Branch, U.S.  EPA Region 6
Letter
Public meeting on 02/27/97, 6:30 p.m., Picher High School,
Picher, Oklahoma

 003075 - 003082
02/25/97
008
James Costello, Senior Attorney
U.S. EPA Region 6
Leslie Nellermoe, Attorney for ASARCO, Heller, Ehrman-White  &
McAuliffe
Letter w/Enclosure
Copy of 02/21/97, memorandum of 02/20/97 meeting, with Jane  N.
Saginaw, Regional Administrator, EPA Region 6

 003083 - 003083
02/26/97
001
Gary Moore, On-Scene Coordinator
U.S. EPA Region 6
Noel Bennett, RPM, U.S. EPA Region 6
Memorandum
Lead speciation
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 003084 - 003087
02/28/97
004
Unspecified
U.S. EPA Region 6
Public
Fact Sheet
"EPA Completes RI and FS for Residential Areas"
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 003088 - 003140
03/03/97
053
Unspecified
U.S. Army Corps of Engineers, Tulsa District
U.S. EPA Region 6
Plan
Quality Assurance Project Plan
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
 003141 - 003143
03/04/97
003
Bruce K. Means, Chair, National Remedy Board
U.S. EPA Headguarters
Myron 0. Knudson, Director, Superfund Division, U.S. EPA
Region 6
Memorandum
National Remedy Review Board recommendations
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
 003144 - 003182
03/04/97
039
Unspecified
U.S. EPA Region 6
Public
Proposed Plan
Residential Areas
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
003183 - 003236
03/06/97
054
Noel T. Bennett, RPM
U.S. EPA Region 6
Leslie C. Nellermoe, Attorney for ASARCO, Heller Ehrman White
& McAuliffe, et al.
Memorandum w/Enclosures
Response to comments about removal action selected in EPA's
Action Memorandum dated 03/21/96
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
003237 - 003238
03/06/97
002
Unspecified
U.S. EPA Region 6
Public and U.S. EPA Region 6 Superfund Site Files
Administrative Record Index
Removal Action, Addendum 4 (Documents indexed are incorporated
by reference into the Removal Action AR File.  Documents may be
reviewed at Region 6 or at the Miami Public Library, Miami, Oklahoma.
 003240 - 003248
03/17/97
009
Community Involvement Section
U.S. EPA Region 6
Tar Creek Mailing List and U.S.
Fact Sheet
Proposed Plan of Action
EPA Region 6 Superfund Site Files
 003249 - 003287
03/17/97
039
Unspecified
U.S. EPA Region 6
Public
Proposed Plan
Residential Areas, Tar Creek Superfund Site, Ottawa County, Oklahoma

003288 - 003292
03/17/97
005
Leslie C. Nellermoe, Attorney for ASARCO Inc.
Heller Ehrman White & McAuliffe
Jane Saginaw, Regional Administrator, U.S. EPA Region 6
Letter
February 20, 1997 Meeting

003293 - 003295
03/17/97
003
Gary Moore, On-Scene Coordinator, Response and Prevention Branch
U.S. EPA Region 6
Mayors and City Councils of Picher, Cardin, Quapaw, Commerce,
and North Miami, Oklahoma
Memorandum w/Enclosure
EPA purchase of limestone for listed cities
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:

COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
003296 - 003298
03/19/97
003
James D. McDurmett, Acting Deputy Commissioner of Indian
Affairs
U. S. Dept. of the Interior
Area Director, Muskogee Area Office and Superintendent, Miami
Agency Office
Memorandum
Town lot rental program

003299 - 003299
03/21/97
001
Gary D. Uphoff, Environmental Management Services Company
EMSC
James E. Costello, Assistant Regional Counsel U.S. EPA Region
6
Letter
Reguest for extension of public comment period

 003300 - 003362
03/27/97
063
Rick L. Congdon, Certified Shorthand Reporter
Unspecified
Public
Meeting Transcript
Public meeting, Picher High School, Picher, Oklahoma, 7:00 p.m.

003363 - 003365
04/01/97
003
James E. Costello, Senior Attorney
U.S. EPA Region 6
Leslie C. Nellermoe, Attorney for ASARCO Inc., et al., Heller
Ehrman White & McAuliffe
Letter
Response to March 17, 1997 letter

003366 - 003367
04/01/97
002
H.A. Caves, Director, Waste Management Division
ODEQ
Myron Knudson, Director, Superfund Division, U.S. EPA Region 6
Letter
ODEQ concurs with proposed plan for Operable Unit 2
-------
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
003368 - 003368
04/01/97
001
Ken Cadaret
OSDH
U.S. EPA Region 6 Superfund Site Files
Summary
Blood Lead Testing Summary, Miami, Oklahoma
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
003369 - 003371
04/04/97
003
Barbara Kyser-Collier, Environmental Director
Wyandotte Tribe of Oklahoma
U.S. EPA Region 6
Public comment letter w/Enclosure
Comments on proposed plan
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:

COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
003372 - 003373
04/07/97
002
Susan Waldron, Community Health Action Management Program
(CHAMP) Project Coordinator
University of Oklahoma Health Sciences Center
Noel Bennett, U.S. EPA Region 6
Public Comment Letter
Comments on proposed plan of action
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
003374 - 003378
04/08/97
005
Karl L. Hatley, Executive Director
Oklahoma Toxics Campaign Fund, Inc.
Community Relations, U.S. EPA Region 6
Letter
Comments on proposed plan of action
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
003379 - 003382
04/09/97
004
Kent Curtis, Site Assessment Manager
Cherokee Nation, Tahleguah, Oklahoma
Noel Bennett, RPM, U.S. EPA Region 6
Letter
Inter-Tribal Environmental Council's comments about proposed
plan of action for lead-contaminated soil at residential areas
-------
DOCUMENT NAME:
DOCUMENT DATE:
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RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
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AUTHOR:
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RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
DOCUMENT NUMBER:
DOCUMENT DATE:
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AUTHOR:
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RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:

DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
003383 - 003384
04/10/97
002
Myron 0. Khudson, P.E. Director Superfund Division
U.S. EPA Region 6
Bruce K. Means, Chair, National Remedy Review Board
Memorandum
Response to National Remedy Review Board recommendations

003385 - 003386
04/11/97
002
Myron 0. Khudson, Director, Superfund Division
U.S. EPA Region 6
Gary D. Uphoff, Principal, Environmental Management Services Company
Letter
Response to March 21, 1997 letter reguesting an extension to
the public comment period regarding the proposed plan

003387 - 003387
04/14/97
001
Cherokee Volunteer Society
Miami High School, Miami, Oklahoma
U.S. EPA Region 6
Public comment letter
Comments on proposed plan

003388 - 003391
04/15/97
004
Lorraine Halinka Malcoe, Principal Investigator
CHAMP
Gary Uphoff, Environmental Management Services Company
Report
Quarterly Report, CHAMP Program, Ottawa County, Oklahoma,
Towns of Picher, Cardin and Quapaw (January 1997 - March 1997)

003392 - 003403
04/15/97
012
Kent Curtis, Site Assessment Manager, Office of Environmental Services
Cherokee Nation, Tahleguah, Oklahoma
U.S. EPA Region 6 Superfund Site
Public Meeting List of Attendees and Presentation Materials
CHAMP Public Meeting at Picher Elementary School in Picher,
Oklahoma, 6:30 p.m.
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003404 - 003404
04/16/97
001
John Gault, Director
Quapaw Tribe of Oklahoma
Donn Walters, Community Involvement Coordinator, U.S. EPA Region  6
Letter
Comments on proposed action
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003405 - 003405
04/17/97
001
Dennis L. Wickliffe, Acting Area Director, Muskogee Area
Office
Unspecified
Superintendent, Miami Agency
Memorandum
Administrative Order Update
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003406 - 003411
04/21/97
006
Geotech
Unspecified
U.S. EPA Region 6
Report
Evaluation of County Roads Used as Haul Routes
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003412 - 003416
04/22/97
005
Tar Creek Field Office
Picher, Oklahoma
Noel Bennett, RPM, U.S. EPA Region 6
Facsimile Transmittal w/Enclosures
Soil samples at disposal area
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003417 - 003418
04/24/97
002
Myron 0. Knudson, Director, Superfund Division
U.S. EPA Region 6
James Graves, Ottawa County Commissioner, Miami, Oklahoma
Letter w/Enclosure
EPA, through contract with Corps of Engineers, willing to
repair road damage  (or reimburse Ottawa County for reasonable
cost of the repair of such damage) which EPA determines to be
caused by EPA response actions.
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003419 - 003419
04/25/97
001
Ken Cadaret
OSDH
Noel Bennett, RPM, U.S. EPA Region 6
Blood Lead Screening Results
Children 6-72 months old, Tri-State Mining District, Oklahoma
Portion, Ottawa County.  July 1, 1995 - November 30, 1996
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003420 - 003420
04/29/97
001
Robert Wilson, Corps of Engineers
U.S. Department of the Army
Noel Bennett, RPM, U.S. EPA Region 6
Memorandum
Flood plain study-related issues
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003421 - 003421
04/30/97
001
Robert Wilson, Corps of Engineers
U.S. Department of the Army
Noel Bennett, RPM, U.S. EPA Region 6
Memorandum
Structures located in flood plain designated as businesses
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003422 - 003423
04/30/97
002
Robert Wilson, Corps of Engineer
U.S. Department of the Army
Noel Bennett, RPM, U.S. EPA Region 6
Memorandum w/Enclosure
Twenty five  (25) year floodplain
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003424 - 003424
05/01/97
001
Robert Wilson, Corps of Engineers
U.S. Department of the Army
Noel Bennett, RPM, U.S. EPA Region 6
Memorandum
Buy-out status
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003425 - 003425
05/01/97
001
Ecology and Environment, Inc.
Consultants for U.S. EPA Region 6
U.S. EPA Region 6 Superfund Site Files
Map
Tar Creek Soil and Sediment Sample Locations
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003426 - 003427
05/04/97
002
Joan Miles, Health Officer, Director
Lewis and Clark City-County Health Department, Helena, Montana
Donn Walters, Community Involvement Coordinator, U.S. EPA
Region 6
Letter
Proposed plan of action
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003428 - 003429
05/06/97
002
Leslie C. Nellermoe, Attorney for ASARCO Inc., et al.
Heller Ehrman White & McAuliffe
Myron 0. Knudson, Director, Superfund Division, U.S. EPA Region  6
Letter
Reguest for extension of public comment period for proposed plan
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003430 - 003498
05/09/97
069
Lisa G. Esayian, Attorney for NL Industries, Inc.
Kirkland & Ellis
Donn Walters, Community Involvement Coordinator, U.S. EPA
Region 6
Letter w/Enclosures
Comments on proposed plan
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003499 - 003500
05/12/97
002
Leslie C. Nellermoe, Attorney for ASARCO Inc., et al.
Heller Ehrman White & McAuliffe
Myron Knudson, Director, Superfund Division, U.S. EPA Region  6
Letter
Reguest for extension of deadline for comments on proposed plan
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003501 - 003503
05/13/97
003
Bob Wilson, Corps of Engineers
U.S. Army
U.S. EPA Region 6
Work Plan
Estimating Costs to Remediate Areas Paved with Chat, Miami, Oklahoma
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003504 - 003504
05/14/97
001
Scott A. Thompson, Environmental Program Director
ODEQ
Kent Curtis, Inter-Tribal Environmental Council, Tahlequah, Oklahoma
Letter
Landowners reluctant to grant access to the U.S. EPA

003505 - 003624
05/15/97
120
Edward B. Cohen, Deputy Solicitor, Office of the Solicitor
U.S. Department of the Interior
Donn Walters, Community Involvement Coordinator, U.S. EPA Region  6
Letter w/Enclosures
Comments on RI/FS Reports, Risk Assessment, and Proposed Plan
for Remedial Action
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003625 - 003626
05/15/97
002
Myron 0. Knudson, Director, Superfund Division
U.S. EPA Region 6
Leslie C. Nellermoe, Attorney for ASARCO, Inc. at al., Heller
Ehrman White & McAuliffe
Letter
Re: May 6, 1997 and May 12, 1997 letters requesting  extension
to public comment period regarding proposed plan

003627 - 003628
05/16/97
002
Kent Curtis, site Assessment Manager, Office of Environmental Services
Cherokee Nation, Tahleguah Oklahoma
Donn Walters, Community Involvement Coordinator, U.S. EPA Region  6
Letter
Supplemental comments to April 8, 1997 letter about  proposed
remediation actions
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003629 - 003631
05/19/97
003
Unspecified
Unspecified
U.S. EPA Region 6 Superfund Site Files
Sampling results
Sampling results for soil repository
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003632 - 003785
05/22/97
154
Gary D. Uphoff
Environmental Management Services Company
Donn Walters, Community Involvement Coordinator, U.S. EPA Region  6
Letter w/Report
Comments on proposed plan of action for residential component
of Operable Unit 2
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 003786 - 003787
05/27/97
002
John Gault, Economic Development Director Quapaw Tribe of Oklahoma
Unspecified
Myron Knudson, Director, Superfund Division, U.S. EPA Region 6
Letter
Proposed remedial action
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003788 - 003789
06/12/97
002
Myron 0. Knudson, Director, Superfund Division
U.S. EPA Region 6
John Gault, Economic Development Director, Quapaw Tribe of
Oklahoma, Quapaw, Oklahoma
Letter
Proposed remedial action
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003790 - 003790
06/12/97
001
Cornelius Flynn
Geotech
Carol Wies, USAGE QAR
Memorandum
Removal action injury summary report
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003791 - 003791
06/16/97
001
Gary Moore, On-Scene Coordinator, Response and Prevention Branch
U.S. EPA Region 6
Phil Clark
Letter
Innovative technology in cleanup of hazardous waste sites
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003792 - 003792
06/19/97
001
Noel Bennett, RPM
U.S. EPA Region 6
Todd Adornato, U.S. Fish and Wildlife Service
Memorandum
Proposed remedial actions
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003793 - 003793
06/19/97
001
Noel Bennett, RPM
U.S. EPA Region 6
U.S. EPA Region 6 Superfund Site Files
Memorandum
Re: Natural Resource Damage Assessment Activities by U.S. Fish
& Wildlife Services
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   003794 - 003794
   06/20/97
   001
   Noel Bennett, RPM
   U.S. EPA Region  6
   Scott Thompson,  ODEQ
   Memorandum
   Proposed remedial actions
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003795 - 003805
   07/0 /97
   Oil
   Billy E. Banks, Chief,  Civil Works  Branch,  Tulsa District,
   Corps of Engineers
   Department  of  the Army
   Noel Bennett,  RPM, U.S.  EPA Region  6
   Letter w/Report
   Chat Survey Report on the City  of Miami,  Oklahoma
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   003806 - 003807
   07/28/97
   002
   Jerry Clifford, Acting  Regional Administrator  USEPA Region 6
   US EPA Region  6
   Ed Chrone, Executive Director  Grand  Gateway Economic Letter
   Application for United  States  Housing  and Urban Development (HUD)  Grant
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   07/31/97
   019
   Tulsa District, Corps  of Engineers
   U.S. Army
   U.S. EPA Region 6
   Investigation
   Netta East Mine Overburden  Investigation at  the  Picher Reunion Park Site
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003808 - 003809
08/01/97
002
Gary Moore, On-Scene Coordinator, Response and Prevention Branch
U.S. EPA Region 6
Charles Gazda, Chief, Response and Prevention Branch, U.S. EPA Region  6
Memorandum
Ottawa Reclamation Authority
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003810 - 003810
08/06/97
001
Quapaw Tribe of Oklahoma
Unspecified
U.S. EPA Region 6 Superfund Site Files
Tribal Resolution #061297
Quapaw Tribe not liable for contamination at the site
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003811 - 003811
08/08/97
001
Robert Wilson, Corps of Engineers
U.S. Army
Noel Bennett, RPM, U.S. EPA Region 6
Memorandum
Tar Creek - Ottawa County Chat Survey
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003812 - 003828
08/15/97
017
Robert Wilson, Tulsa District Office, Corps of Engineers
U.S. Army
Noel T. Bennett, RPM, U.S. EPA Region 6
Survey
CHAT Survey, Miami, Oklahoma
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