PB98-964201
                                 EPA 541-R98-047
                                 October 1998
EPA Superfund
      Record of Decision:
       Lincoln Creosote Site
       Bossier City, LA
       11/26/1997

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                             LINCOLN CREOSOTE SITE
                             BOSSIER CITY, LOUISIANA
                               RECORD OF DECISION
                                   DECLARATION

 SITE NAME AND LOCATION

 Lincoln Creosote Site, Bossier City, Louisiana


 STATEMENT OF BASIS AND PURPOSE

       This decision document presents the selected remedial action for the Lincoln Creosote Site
 in Bossier City, Louisiana, developed in accordance with the Comprehensive Environmental
 Response, Compensation, and Liability Act (CERCLA), and, to the extent practicable, the
 National Contingency Plan. This decision is based on the Administrative Record for the site.

       The State of Louisiana concurs on the selected remedy.


 DESCRIPTION OF THE SELECTED REMEDY

       EPA has selected no further remedial action at the Lincoln Creosote Site.  Previous
 removal actions have eliminated existing and potential threats to human health or the
 environment. The Risk Assessment documents that the removal actions taken on the Site
eliminate the need for further response action, and that the Site poses no current or potential
threat to human health or the environment.

       The  no further action remedy does not include any element of future work such as
maintenance or monitoring, engineering controls, or institutional controls. Unlimited Site access
can occur without unacceptable exposure to hazardous substances.


DECLARATION STATEMENT

       EPA has determined that its response at this site is complete and no further action is
 necessary at this site. Therefore, the site now qualifies for inclusion on the Construction
 Completion List. Because this remedy will not result in hazardous substances, pollutants or
 contaminants remaining on-site above concentration levels that allow for unrestricted use and
 unlimited exposure, the five year review will not apply to this action.
                          	
                   //                                    Date
           onal Administrator

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                             LINCOLN CREOSOTE SITE
                             BOSSIER CITY, LOUISIANA
                               RECORD OF DECISION
                                DECISION SUMMARY
 SITE NAME, LOCATION AND DESCRIPTION

 The Lincoln Creosote Site ("Site") is located in Bossier City, Louisiana, and consists of a 20-acre
 industrial area that includes the former location of a wood treatment plant. (Hereinafter the
 former wood-treatment plant area is referred to as the plant. That is, when this Record of
 Decision (ROD) refers to the plant it means the approximately 20-acre area which is identified on
 Figure 1 as the plant area.)  In addition to the plant, the Site also includes parts of an adjacent
 residential neighborhood which has been contaminated by storm water runoff from the wood-
 treatment facility that operated on the plant.  The area of the contaminated portions of the
 residential neighborhood is shown on Figure 6. It should be noted that in certain earlier
 documents (e.g.. work plans, and sampling analysis reports) the contaminated parts  of the
 residential neighborhood were referred to as "off-site"; however, the Site includes those areas
 which were previously referred to as "off-site"  as well as the plant. The map which is Figure 5
 describes the Site area. The Site is largely undeveloped, with a few light industrial properties
 located on about 3 acres of the northwest part of the Site. The areas immediately surrounding the
 plant to the north, northeast, south and west are primarily residential with some commercial areas
 interspersed. Two apartment complexes, the Northpark Apartments and Cloverdale Apartments,
 are located on the Site. Small areas of commercial development also are present on the Site, and
 a Louisiana and Arkansas Railroad right-of-way is located in the Southern part of the Site.

 SITE HISTORY

 A wood-treatment facility operated on the plant from about  1935 through 1969. Since 1969, no
activities have been reported at the Site except for light commercial activities in the  northwest
comer which have been underway since 1985 (electrical parts distributor and mini-warehouse
facility). Wood products such as  railroad ties and utility poles were pressure treated at the plant,
using creosote, chromated copper-arsenate (CCA) and pentachlorophenol (PCP) as wood
preservatives. The compounds used  for wood treatment contained metals, a number of semi-
volatile organic base-neutral  extractable compounds such as polynuclear aromatic hydrocarbon
(PAHs).
Lincoln Creosote Site
Record of Decision
Pagcl

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The CCA, PCP, and PAHs are hazardous substances and were dumped, spilled and disposed of
on the plant in sludges, sediments, wastewater, process residuals, preservative drippings and
spent formulations.

The original wood treating process area was located in the western portion of the plant, and was
about 10,000 square feet in area. Untreated wood was stacked in the northeastern part of the
plant in an untreated-wood storage yard that measured approximately 4 acres.  The untreated-
wood storage area included buildings and machinery used for timber sizing, pole machining, and
wood drying.  Piles of untreated wood spread to other plant areas as the plant grew in the 1960's.

                                        Figure 1
                                                        Ponding Area
                                              Lincoln Creosote Site
Lincoln Creosote Site
Record of Decision
Page 2

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 Treated wood generally was stacked in the southern portion of the plant in a treated-wood storage
 area which occupied approximately 30,000 square feet of the plant. Treated wood piles extended
 to other parts of the plant in the 1960's.  Several railroad spurs used to transport wood were
 located throughout the plant.  These spurs connected with the railroad line located along the
 southern boundary of the plant. A petroleum pumping station was located slightly southeast of
 the wood-treating process area. This pumping station reportedly was operated from 1946 to
 1966.

 Wood-treating wastes arid PCP-, CCA- and PAH-contaminated soil were left on the plant when
 the wood-treating facility was closed. This release of hazardous substances resulted in the need
 for later investigation and remediation of the Site. Periodic releases of hazardous substances
 during plant operation may  have occurred as a result of chemical handling, leaks and spills
 during the treatment processes.  During facility operation and after the wood-treatment facility
 was closed at the plant, surface impoundments used to collect facility waste overflowed,
 resulting in the release of hazardous substances onto plant soils. The overflow from the surface
 impoundments migrated along drainage pathways located downgradient from the plant thereby
 contaminating those pathways with hazardous substances including PCP, CCA, and PAHs.
 Some of these migrating hazardous substances contaminated soil in the residential
 neighborhoods located on the Site.

 ENFORCEMENT ACTIVITIES

 In April 1994, Joslyn Manufacturing Co.  ("Joslyn") approached EPA, and proposed to
 undertake a removal action  to address contamination found in a drainage ditch basin located in a
 neighborhood northeast of the plant.  Historically, contaminated rainwater runoff from the plant
 collected in this ditch. Joslyn prepared a work plan and a draft Engineering Evaluation and Cost
 Analysis (EE/CA) and submitted it to EPA for review in  late July 1994.  An EE/CA is an
 analysis of removal alternatives. In August 1994, EPA made the decision to conduct a non-time-
 critical removal in the neighborhood northeast of the plant.  On August 24, 1994, EPA issued
 special notice letters to five  potentially responsible parties (PRPs). The notice letters requested
the PRPs to perform or finance the removal action to address the contamination found in the
neighborhoods near the plant.   Only Joslyn responded to the notice with a good-faith offer.

 In late December  IV'M, Joslyn submitted a revised EE/CA to EPA, along with a pre-excavation
sampling plan for the neighborhood.  EPA approved the pre-excavation sampling plan on
January 20, 1995, and sampling of the neighborhood began on January 25,1995. EPA held a
public comment period regarding the EE/CA from June 29, 1995 to July 29, 1995.  Utilizing the
 EE/CA and the sampling results, EPA selected a removal action to address the contaminated soil
 in the neighborhoods  located near the plant. EPA memorialized its decision in an Action
 Memorandum issued on August 17, 1995. EPA's selected removal action called for excavation
 of residential soils containing concentrations of wood treatment product residuals above an
Lincoln Creosote Site
Record of Decision
Page 3

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                                                                                                                               HISTORICAL DRAINAGE
                                                                                                                               PATHWAY/STORM SEWERS
                                                                                                                               CURRENT OPEN CMTCH
                                                                                                                               SAMPLE LOCATION WHERE TOTAL BAP
                                                                                                                               EQUIVALENT PAHi CONCENTRATIONS
                                                                                                                               2. 30OO
SAMPLE LOCATION  WHERE PAH. WERE
DETECTED ABO\C BACKGROUND UPPER
TOLERANCE LJUJlT (UTL)

SAMPLE LOCATION  WHERE NO PAM« WERE
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BACKGROUND STATION LOCATION

RAILROAD

ESTIMATED  AREA WHCR£ BAP EQUIVALENT
PAHs CONCENTRATIONS iJ.OOO )><)/*<)

ESTIUAIEO  AREA OF SITE- ATTRIBUTABLE
PAH CONTAMINATION

ESTIMATED  AREA Of PAH CONTAMINATION
MTH UNCERTAIN ATTRIBUTION
                                               F1CIIKK 2
     BEN20 (A) PYRENE
(BAP)  EQUIVALENT-AFFECTED

       SOIL  *3 mg/kg

     LINCOLN CREOSOTE SITE
     BOSSIER  CITY. LOUISIANA
       US  EPA REGION  V1
          ARCS rSI/RI	

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 action level of 3 parts benzo(a)pyrene equivalents per million parts soil (ppm). Under the removal
 action, excavated soil was disposed of off-site, and excavated areas were backfilled with clean
 soil.

 EPA entered into an Administrative Order on Consent with Joslyn to implement the removal
 action. The effective date of the Order was November 27, 1995.  After obtaining access
 agreements from affected property owners, Joslyn began the removal action in May 1996.
 Approximately 15,000 tons of contaminated soils were removed from the affected areas shown in
 Figure 3, and replaced with clean backfill. The affected areas were regraded and landscaped. The
 removal work was completed in October 1996.

 HIGHLIGHTS OF COMMUNITY INVOLVEMENT

 EPA developed a Community Involvement Plan in September 1994 in order to actively involve
 the neighborhoods and the rest of the public in the Superfimd process at the Lincoln Creosote
 Site.  Several open houses and workshops were held in the community starting in  1994.  Fact
 sheets have been distributed on four occasions to the approximately 220 persons on the mailing
 list for the Site.

 In a newspaper announcement dated September 17,1997, which was published in the Shreveport
 Times, a major local newspaper of general circulation, EPA solicited public comments on EPA's
 Proposed Plan for the long-term remediation of the Site. That same newspaper announcement
 informed the public of a public meeting which EPA held to solicit oral comments on the Proposed
 Plan.  The meeting was held on September 29, 1997. The purpose of the Proposed Plan was to
 inform the public of the recommended alternative for remedial action at the Site (in this case EPA
 had decided to take no action), and to solicit review and comment by the public.  Specifically, the
 objectives of this Proposed Plan were as follows:

       Summarize the circumstances that resulted in the selection of  the no action alternative;
          and

       Solicit public review and comment on the proposed no action alternative and on
       information contained in the Administrative Record File.

Public comments on the Proposed Plan and on the Administrative Record File were accepted
during the period beginning September 18, 1997 and ending October 17, 1997. No written
comments were received during the period. Additionally, oral comments were accepted at the
public meeting held on September 29, 1997.  EPA has considered and responded to all significant
comments received during the public comment period either through a direct reply at the public
 meeting or in a document called a Responsiveness Summary. A transcript from the public
 meeting is part of the Administrative Record.  The Responsiveness Summary is attached to this
 ROD.
Lincoln Creosote Site
Record of Decision
PageS

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 The purpose of this ROD is to document EPA's  final decision, regarding the remedial action
 (i.e.. no further action) to be taken at the Site. The purpose of the ROD is to, as appropriate.
 document all facts, analyses of facts, and site-specific policy determinations considered in the
 course of carrying out the requirements of the National Contingency Plan (NCP)  in a level of
 detail appropriate to the situation (the NCP can be found in the Code of Federal Regulations
 (CFR) in Title 40 at Part 300).

 SCOPE AND ROLE OF RESPONSE ACTION

 The Lincoln Creosote Site was proposed to the National Priorities List (NPL) in January 1994.
 The NPL is the list of uncontrolled hazardous substance releases in the United States that are
 priorities  for long-term remedial evaluation and response.  The NPL is compiled by EPA. The
 proposed  Site listing included the plant and the surrounding residential areas.  At the time that
 the Site was proposed to the NPL, an  action was taken  by  LDEQ to address  contaminated soils
 remaining on the plant after the cessation of wood treating activities. The work was performed
 by Joslyn under LDEQ oversight, and resulted in the removal of more than 100,000 cubic yards
 of contaminated soils from the plant. This work is documented in  a Removal  Action Report
 dated March 18, 1994, which is part of the Administrative  Record for this ROD. In a letter dated
 August 22, 1997, LDEQ notified EPA that it had determined that conditions on the plant were
 protective of human health and the environment, and that, therefore, LDEQ had decided that all
 response action at the plant was complete and that no further  action was anticipated.

 As explained above, a second action taken at the Site was performed by Joslyn, under EPA
 authority pursuant to CERCLA.  The second action addressed hazardous  substances
 contamination in neighborhoods adjacent to the plant. The hazardous substances were chemical
 residuals which migrated from the wood treatment operation, and contaminated neighborhood
 soils.  This work is documented in a Removal Action Report dated February 1997 which is also
 part of the Administrative  Record for this  ROD.

 As explained above, Joslyn, under LDEQ oversight, addressed the contamination on the plant,
 and Joslyn, under EPA oversight, also  addressed the contamination on the rest of the Site.
 Therefore, since these previous responses eliminated the need for further remedial responses at
the Site, EPA has decided  to take no further response action at the Site. EPA's decision is
documented  in this ROD.  The A  •linistrative Record is the documents which are the basis for
EPA's decision. The ROD addresses all the problems associated with hazardous substance
contamination on the entire Site (i.e., the neighborhoods and the plant). No other operable units
are defined for the Site.
Lincoln Creosote Site
Record of Decision
Page 6

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      LECENO


EXCAVATION GREATER THAN OR
EQUAL to 2 FEET

EXCAVATION LESS THAN 2 FEET

AREAS WITHIN THE LATERAL LIMITS OF
EXCAVATION COVERED WITH A STRUCTURALLY
STABLE LOW PERMEABILITY MATERIAL

SITE  BOUNDARY
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 SITE CHARACTERIZATION

 Activities at the Site generally can be divided into the response actions taken to address the
 contamination on the plant, and the response actions taken to address the contamination of the
 neighborhoods near the plant.  The cleanup of the plant was generally undertaken by Joslyn under
 LDEQ oversight. The cleanup of the neighborhoods was generally undertaken by Joslyn with
 EPA oversight.  LDEQ has determined that conditions on the plant are now protective of human
 health and the environment, that all response action on the plant is complete, and that no further
 construction is anticipated, and EPA is relying on LDEQ's determination with respect to the
 plant. That is, EPA is basing its decision not to take further action at the plant on LDEQ's
 determination. With respect to the neighborhoods, EPA has conducted its own Remedial
 Investigation (RI) which included a baseline risk assessment to characterize the risks to human
 health and the environment that were posed by the contaminants prior to the response actions
 taken by Joslyn under EPA oversight. As explained below, based on the Risk Assessment, EPA
 believes that no remedial action is necessary to ensure protection of human health and the
 environment in the neighborhoods. In short, EPA has determined, that no remedial action is
 necessary at the Site in order to ensure protection of human  health and the environment.

 In 1985, EPA conducted an investigation of the plant. The analytical samples of soil collected on
 the plant indicated high concentrations of hazardous substances including creosote-related semi-
 volatile organic compounds, pentachlorophenol, and chromated copper arsenate.  A remedial
 investigation of the plant was completed by Joslyn, a former owner and operator of the plant,  in
 1989 under LDEQ oversight.  During this investigation, significantly elevated concentrations of
 hazardous substances including numerous creosote-related semi-volatile compounds,
 pentachlorophenol, chromium, and arsenic were discovered in the soils on the plant.  Joslyn began
 remedial activities at the plant in February 1992 under LDEQ oversight.  Remedial activities
 included excavation and off-site disposal of contaminated soils. Currently,  the plant  is largely
 abandoned and undeveloped except for the northwest corner of the plant where there is an
 electrical supply company and a mini-warehouse complex.

 Due to a request from a citizen who lives in the neighborhood northeast of the plant, EPA
 conducted an Expanded Site Inspection (ESI) in March  1992. EPA found hazardous substances
 including creosote-related semi-volatile organic compounds at concentrations significantly above
background levels i" the on-Site neighborhood surrounding the plant. Based upon that d ta, the
 Site was proposed for the National Priorities List on January 18, 1994 (59 :ed. Reg. 25t .>).

Based on information provided by neighborhood residents, in March 1994, EPA began planning
additional sampling in the neighborhoods near the plant. EPA took environmental samples in the
 neighborhood during the period from June 1994 to July 1994.  The results of this investigation
 are contained in the ESI/RI Report.  Site-attributable constituents that EPA investigated include
 semi-volatile organics, metals, and dioxin/furans. The findings of the ESI/RI are presented below.
Lincoln Creosote Site
Record of Decision
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 Nature and Extent of Contamination - Polynuclcar Aromatic Hydrocarbon (PAH)
 Prior to the removal action taken in the neighborhoods near the plant, approximately 16 PAH
 compounds and pentachlorophenol (PCP), attributable to the wood-treating chemicals formerly
 used at the Lincoln Creosote Site were present in  soils and ditch sediments in the neighborhood
 near the plant.  PAHs were frequently detected in  ESI/RI soil samples at concentration levels
 above PAH concentrations found in soil samples taken in areas near the Site for use as
 background comparison values. Total PAH concentrations in the affected soil  and ditch sediment
 were as high as 328,290 micrograms per kilogram (wg/kg) and 24,750 wg/kg, respectively. PCP
 was detected in soil at concentration levels above  background comparison values much less
 frequently than the PAHs, and was generally found only where elevated PAH  concentrations
 were also present.  PCP concentrations in  the affected soil were as high as 8,900 wg/kg, and PCP
 concentrations in the affected sediment were as high as 740 wg/kg.  Total benzo(a)pyrene (BAP)
 equivalent concentrations were calculated based on the reported PAH results.  Total BAP
 equivalent concentrations provide a means of evaluating total PAH as if it were composed solely
 of BAP, the most toxic of the PAH.compounds. The estimated extent of total  BAP equivalent
 affected soil as it existed before the removal action is shown in Figure 2.  Affected soils were
 found to the depth  of 2 feet below ground  surface  in Site neighborhoods.

 Nature and Extent of Contamination - Metals
 Prior to the removal action, copper, chromium, and arsenic attributable to the chromated copper
 arsenate (CCA) used  for wood treating at the Lincoln Creosote plant were found in Site
 neighborhoods in certain locations in concentrations exceeding the background comparison
 levels. The metals sampling results found:

 •      Copper-affected soils occurred at scattered locations within the Site, primarily within or
       immediately adjacent to the historic plant drainage pathways.  The highest copper
       concentration found was 47,000 wg/kg.

 •      Chromium-affected soils occurred  at scattered locations within the Site, generally along
       the historic  plant drainage ways. The highest chromium concentration  found is 71,200
       wg/kg.

•      Arsenic-affected soils occurred at scattered locations within the Site that were more
       extensive than those of copper and chromium-affected soils.  In addition to the arsenic in
       ureas along the historic plant drainage ways, elevated arsenic levels were found at some
       of the residential properties immediately west and south of the Lincoln Creosote plant.
       An unusually high 770,000 wg/kg concentration of arsenic was found west of the plant.

 Except for the certain  locations described above, prior to the removal action, the concentration
 levels of copper, chromium, and arsenic generally  detected in the Site neighborhood soils were
 not especially high in  most cases when compared  to the local and regional background levels.
 Most of the concentration levels of these contaminants which exceeded background levels were
 within the same order of magnitude as the local background results; nonetheless, as explained
 below, some of these concentrations above background level did pose a health threat.
Lincoln Creosote Site
Record of Decision
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 Nature «nd Eitent of Contamination -Dioiin/Furans
 Prior to the removal action, dioxin/furan compounds, organic byproducts of the wood-treating
 process, were present in soil and ditch sediments found in Site neighborhoods in concentrations
 above the background comparison values. Total 2,3,7,8 TCDD equivalent concentrations were
 calculated based on the reported dioxin/furan results. Total 2,3,7,8 TCDD equivalent
 concentrations provide a means of evaluating total dioxin/furan results as if it were composed
 solely of 2,3,7,8 TCDD, the most toxic of the dioxin/furan compounds. This 2,3,7,8 TCDD
 equivalent process is similar to the calculation of a total BAP equivalent described above.  Both
 processes are used by EPA to help produce a conservative estimate of the risk to human health.
 The 2,3,7,8 TCDD equivalent concentrations for dioxin/furans for the study area samples were
 found up  to .4 ug/kg.  The extent of dioxin/furan contamination coincides with the estimated area
 of PAH-affected soil/sediment.

 SUMMARY OF SITE RISKS

 Risks at the Site were generally addressed in two operations. The risk at the plant was generally
 addressed by Joslyn under LDEQ oversight. The risk in the neighborhoods was generally
 addressed by Joslyn with EPA oversight.  LDEQ has determined that conditions on the plant are
 now  protective of human health and the environment, that all response action on the plant is
 complete,  and that no  further construction is anticipated, and EPA is relying on LDEQ's
 determination with respect to the plant. That is, EPA is basing its decision not to take further
 action at the plant on LDEQ's determination. With respect to the neighborhoods, EPA has
 conducted its own RI and Risk Assessment.  As explained below, based on the Risk Assessment,
 EPA believes that no remedial action is necessary to ensure protection of human health and the
 environment in the neighborhoods. In short, EPA has determined, that no remedial action is
 necessary  at the Site in order to ensure protection of human health and the environment.

 EPA conducted a human health and ecological Risk Assessment for the Site neighborhoods.  The
 approach used was in accordance with EPA Risk Assessment guidance. The objectives of the Risk
 Assessment were to assess health risks which contaminated soil and sediment posed to current
 and hypothetical future residents of the neighborhoods near the plant, and to evaluate the impact
 of contaminated soils and  sediments on local wildlife in the neighborhoods.  In this ROD EPA
 calls each medium (e.g.. soil, water, air, sediment), which may carry contamination to the human
 body or to the environment, an "exposure pathway." The Risk Assessment examines the soil
 and sediment exposure pathways. In this ROD, EPA calls the mechanism through which
contamination may enter the human body (i.e.. ingestion, inhalation, skin absorption) an
"exposure route." The baseline risk assessment process used for Super-fund sites is illustrated in
 Figure 4. The plant area was not included in the baseline risk assessment because the
 contamination on the plant was removed during the comprehensive State-lead removal, and the
 excavated  soils were replaced with clean backfill, and because the LDEQ has determined that the
 plant poses no threat to human health or to the environment.

 A draft Risk Assessment for the neighborhoods near the plant was prepared by Roy F. Weston,
 Inc. for EPA in January 1995. The draft Risk Assessment was revised based upon new data,
Lincoln Creosote Site
Record of Decision
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 acquired in 1996 and 1997 after removal of a large volume of soil and sediment, and finalized.
 The Risk Assessment is not based on data gathered regarding the specific behavior of Site
 residents.  Instead the Risk Assessment is based on certain assumptions regarding human
 behavior in general.  These assumptions are consistent with EPA policy and were developed
 through EPA study and experience. Risks were calculated for humans living on the Site under
 various scenarios including current use scenarios and future use scenarios.

 The results of the Risk  Assessment are not exact estimates of the number of individuals who will
 develop health problems. Rather, they are a statement of the relative magnitude of risk if the
 assumed exposure occurs. Risk assessment is a tool  which, when performed using the standard
 algorithms and assumptions, provides risk managers with a way to quantitatively compare sites
 and to set priorities in the interest of protecting human health.

 Data Evaluation and Reduction
 Data evaluated for the human health component of the Risk Assessment included soil samples
 from neighborhood areas taken at sampling depths 0-6" and/or 0-24'". Samples were collected
 in three study zones which were called exposure pathway scenarios (EPS), and numbered EPS 1,
 EPS 2 and EPS 3. These study zones were  designated based on the proximity of the study zone
 to the plant, and on the land use in each study area respectively. The sampling locations
 evaluated for EPS 1, EPS 2 and EPS 3 are shown on  Figures 5 and 6.
       •   EPS 1 - Includes residential areas in close proximity to the plant.

       •   EPS 2 - Includes residential and non-residential areas more distant from the northern,
           western, southern, and eastern boundaries of the plant.

       •   EPS 3 - Includes non-residential areas northeast of the plant. These areas are distant
           from the plant boundaries, and EPA assumes that these areas will be used for
          residential purposes in the future.

Constituents of Potential Concern (COPCs) (i.e.. the  chemicals which EPA believed to pose a
risk) chosen for evaluation in the Risk Assessment included PAHs,  PCP, hazardous metals, and
dioxin/furans. The Risk Assessment calculated the concentration of COPCs at the point at which
humans may be  -xposed to the COPCs (the "exposure point").  The Risk Assessment used
statistical methods which assure that exposure point concentrations were determined with 95%
confidence.  However,  in order to be realistic, if the statistical method utilized projected an
exposure point concentration that  exceeded the maximum concentration of a COPC found in the
sample with the highest concentration of the COPC in queston, the maximum concentration was
used rather than the statistically-derived  concentration. The exposure point concentrations for
the three study zones are presented in Tables 1-4.

 Human Health Exposure Assessment
 Figure 7 is a conceptual model of the Site detailing the primary and secondary sources of
 COPCs, potential COPC migration pathways, exposure  pathways, and exposure routes evaluated
 for the human receptors in EPS 1, EPS 2 and EPS 3.  For the current residents (EPS 1  and EPS

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 Record of Decision
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 2), 0 to 6 inch soil samples were used to evaluate the soil-related exposure routes, except for fruit
 and vegetable consumption which was based on the 0 to 24 inch soil samples. For the
 hypothetical future residents (EPS 3), the 0 to 24 inch soil samples were used for the soil-related
 exposure routes.

 Both reasonable maximum exposure (RME) and central tendency exposure (CTE) scenarios were
 developed for EPS 1, EPS 2 and EPS 3. The RME estimate is designed to be a measure of "high-
 end exposure" (i.e.. the maximum exposure that a hypothetical person could face) and the CTE
 estimate provides a measure of "average" exposure (i.e.. the average exposure that a hypothetical
 person would face).

 The following subsections provide a description of probable circumstances ("scenarios") under
 which people living on the Site (or who may live on the Site in the future) may be exposed to
 COPCs in the media of concern (i.e.. soil and sediment). This information is summarized in
 Table 5.

 Current Use Scenarios
 EPS I - Exposure to Soil and Sediment in Residential Areas Closest to the Plant

 For EPS 1, the neighborhood closest to the plant, EPA evaluated the risk from soil and sediments
 under an RME scenario and under a-CTE scenario.  For the RME scenario, EPA evaluated the
 risk to a current resident (child and adult). For the CTE scenario, EPA evaluated the risk to a
 five- to  13-year-old current resident. The soil and sediment sampling locations included in the
 risk assessment for EPS  1 are shown on Figures 5 and 6. Under the current resident scenario for
 EPS 1, the Risk Assessment evaluated the risk to residents living in the Northpark Apartments,
 and the risk to the residents living in areas just north of the plant. In EPS 1, the current residents
 were assumed to be exposed to soil during outdoor activities such as gardening, yard work, and
 recreational activities.  A soil ingestion rate of 200 milligrams per day (mg/day) was  used for the
child residents and an ingestion rate of 100 mg/day was  used for the adult residents.  A year-
round exposure to soil of 350 days/year was assumed for both the RME and CTE scenarios.
The exposure duration for the CTE scenario was assumed to be nine years which represents the
national average estimate of time spent at one residence. The exposure  duration for the RME
scenario was divided into two  i le groups. A six-year duration was evaluated for young children
aged one to six, and a 30-year exposure duration was used for an adult.  The thirty-year RME
exposure duration assumed that the adult was exposed for six years as a child and 24 years as an
adult (30 years is the national upper 90th percentile estimate of time spent at one residence).  For
the CTE scenario, the exposure duration of  nine years assumed two years of exposure as a child
and seven years of exposure as an adult. A resident over the age of six is considered an adult for
 risk assessment purposes.

 In EPS 1, in addition to soil exposure, the current residents (under both the CTE and RME
 scenarios) were also assumed to be exposed to sediment in the drainage ditches, which are
 located north and west of the Northpark Apartments, during outdoor recreational activity.  An
 exposure frequency of 52 days/yeu. was assumed for the sediment pathway based on one day per

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 Record of Decision
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                                Data Evaluation
                       • Gather and analyze relevant sue data

                       • Identify chemicals of potential concern
• Identify exposed populations

• Identify potential exposure pathways

• Estimate exposure concentrations for
 identified pathways

• Estimate chemical intakes for these
 pathways
• Collect qualitative and quantitative
 loxicity information

• Determine appropriate ujxicity values
                                 Cfcantfacfaatka
                        • Charaoerize potential for occurrence
                         of adverse health effects
                         - Estimate carcinogenic risks
                         - Estimate noncarcinogenic hazard
                           quouenu
                        • Summarize rsk information
                             Uncertainty Aiudysas
                    • Data Evaluation
                      - Sampling considerations
                      - Comparison with background
                    • Exposure Assessment
                      - Exposure scenarios
                      - Exposure assumptions
                    • Toxiciry Assessment/Risk Characterization
                      - Noncarcinogenic effects
                      - Carcinogenic effects
                      - Risk estimates
                                                    LINCOLN CREOSOTE SITE
                                                 BOSSIER CITY, BOSSIER PARISH
                                                            LOUISIANA
                                                           FIGURE 4
                                          SCHEMATIC OF THE HUMAN HEALTH
                                                RISK ASSESSMENT PROCESS

-------
                                                                                                                                                                                      N
                                                                                                                                                                        LEGEND:
                                                                                                                                                                        SITt PROPERTY BOUNDARY
                                                                                                                                                                        HISTORICAL  DRAINAGE
                                                                                                                                                                        PATHWAY/STORM SCwERS
                                                                                                                                                                        CURRENT OPEN DtTCM
                                                                                                                                                                        SOIL SAMPLE LOCATION
                                                                                                                                                                        SEDIMENT SAMPLE LOCATION
                                                                                                                                                                        BACKGROUND SAMPLE LOCATION
                                                                                                                                                                        RAILROAD
                                                                                                                                                                        EPS - I CURRENT OFFSITE  RESIDENTS
                                                                                                                                                                        EPS - 2 CURRENT OFFSITE  RESIDENTS
                                                                                                                                                                        EPS - 3 FUTURE OFFSITE RESIDENTS
                                                                                                                                                                     NOTE:
                                                                                                                                                                     SEDIMENT BACKGROUND SAMPLES SEDb
                                                                                                                                                                     AND  SED7  ARE LOCATED APPROXIUATEL i
                                                                                                                                                                     1 MILE SOUTH-SOUTHWEST OF THE  SITT
                                                                                                                                                                     (SEE  FIGURE 2-1)
on or •*••*• OTT. LA
ftjMnaai tun (iiim-
Ililtt-l. IIIUI.))
                                                                                                                                                                                   FIGURE  5
                                                                                                                                                                           PRE-REMEDIAL  ACTION
                                                                                                                                                                               SOIL AND SEDIMENT
                                                                                                                                                                            SAMPLING  LOCATION MAP
                                                                                                                                                                               LINCOLN CREOS01C SITE
                                                                                                                                                                               BOSSIER CITY.  LOUISIANA
                                                                                                                                                                                 US fl'A (Vr.ttON VI
                                                                                                                                                                                    ARCS fSI/KI     	
n.u
IAN '!••
       5    IW.HI
I4KO3O4/O75  I    *'• '•""»

-------
               VERTICAL SOIL SAMPLE

               VERTICAL SECXMENT  SAMPLE

               LATERAL SAMPLE COLLECTED  IN  IMS

               LATERAL SAMPLE COLLECTED  IN  1996

               PROPERTY BOUNDARY

               LATERAL uurr or EXCAVATION

               SITE BOUNDARY

               EPS1

               EPS2

               EXCAVATION AREA
NOTE: SB 103. SB 104 AND SB 105 SON. BORINGS
      SAMPLED IN THE VICINITY OF THE DITCH
      AND SOUTH  OF GREEN ACRES JUNIOR
      HIGH  SCHOOL ARE  NOT SHOWN ON THIS
      FICURE.
                      150
                                    300

                                    rtn
                  FIGURE A
POST  REMEDIAL CONFIRMATORY SAMPLE LOCATIONS
           AND AREA  OF EXCAVATION
            LINCOLN CREOSOTE SITE
            Bonwr City. LouMono


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       PRIMARY
       SOURCES
  PRIMARY
  RELEASE
 MECHANISM
SECONDARY
 SOURCES
        SECONDARY
         RELEASE
        MECHANISM
                                                                                  PATHWAY
  EXPOSURE
   ROUTES
                                                                                                                         RECEPTORS
   WOOD TREATMENT
    PROCESS SPENT
      CHEMICAL
     PRODUCT AND
     WASTEWATER
      (ON-SITE)
 WASTEWATER
    AND
  CHEMICAL
  PRODUCT
 DISCHARGE
         1
      CHEMICAL
   PRODUCT STORED
   IN IMPOUNDMENTS
     AND TANKS
      (ON-SITE)

    TREATED WOOD
      CONTAINING
      CHEMICAL
      PRODUCT
      (ON-SITE)
         I
                                                                  I
                    STORMWATER
                      RUN-OFF
                    DRAINAGE
                   DITCH AND
                  IMPOUNDMENT
                   SEDIMENTS
                   (ON-SITE)
                                            1
                    SOIL IN
                    PRIMARY
                  SOURCES AND
                    ADJACENT
                 AREAS, foN-S
                 AND (OIT
     eiivi
     ;I-SITE)
     -SITE)
                       I
L
                                                                                               RME
                                                                                            SCENARIO
                                                                                           CTB
                                                                                        SCENARIO
                       DUST
                     RELEASED
                     INTO THE
                        AIR
                                                         INCESTION
                                                                                                   DERMAL
                                                                                                   CONTACT
                                                                            INGESTION
                                                                                                   DERMAL
                                                                                                   CONTACT
  INHALATION
 OF AIRBORNE
     SOIL

  INCESTION
OF HOMEGROWN
   PRODUCE
DATD  08/05/97
V.O.NO.:  17208B78H97
                                                                                     FIGURE 7
                                                                              CONCEPTUAL  SITE MODEL
                                                                         HUMAN HEALTH RISK  ASSESSMENT
                                                                              LINCOLN CREOSOTE  SITE
                                                                              BOSSIER CITY. LOUISIANA

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                                                TABLE 1
                   Exposure Point Concentrations for Chemicals of Potential Concern in Soil (0-6")
                                      Current Off-Site Resident (EPS 1)
Chemical
Organica
te(2-Elhytwxyf)phthalate
Butyt>enzytohtfca/ate
Carbazofe
PAHt
Acenaphthytone
Anthracene
B«nzo(a)anthracene
Benzo(a)pyrene
Benzo
-------
                                                TABLE 2

               Exposure Point Concentrations for Chemicals of Potential Concern in Sediment (0-6")
                                  Current Off-Site Residential Area (EPS 1)
I Chemical
rganics
bis(2-Ethyfoexyl)phthalate
Butylbenzytphthalate
Carbazole
Oibenzofuran
Diethytphthalate
Di-n-butytprithalate
Dioxins / furans (e)
(as 2,3,7,8 - TCDD equKralerrtsl
Hexachlorobenzene
Statistical
Distribution
of Data (a)

Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
....
Lognormal
95% UCL of
Mean Concentration
(mg/kg) (b)

2.44E+02
3.50E+01
888E-01
3.99E+06
2.95E+08
2.74E+00
1.72E-05
9.27E+02
Maximum
Concentration
(mg/kg) (c)

1.60E+00
7.20E-02
1.50E-01
1.90E-02
1.50E-02
1.50E-01
5.83E-05
1.70E+00
Exposure Point
Concentration
(mg/kg) (d)

1.60E+00
7.20E-02
1.50E-01
1.90E-02
1.50E-02
1.50E-01
1.72E-05
1.70E+00
PAHs
Acenaphthene
Acenaphthylene
1 Anthracene
Benzo(a]anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(g,h,i)perylene
Benzo(k)fluoranthene
Chrysene
Dibenzo(a.h)anthracene
Fkioranthene
Fluorene
lndeno(1 ,2.3-cd)pyrene
2-Methytnaphthalene
Naphthalene
Phenanthrene
Pyrene
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
2.95E+06
1.89E+08
1.85E+04
2.60E+00
1.72E+01
1.01E+02
1.44E+04
2.81E*00
2.42E+02
2.49E+00
3.26E+06
7.70E+06
1.82E+01
7.70E+06
248E+04
7.07E-01
3.97E+01
2.00E-02
1.60E-02
1.30E+00
1.30E+00
2.30E+00
3.60E*00
2.00E+00
1.80E*00
6.70E*00
8.60E-01
9.20E-01
1.70E-02
2.80E*00
1.70E-02
3.10E-02
3.70E-01
980E-01
2.00E-02
1.60E-02
1.30E+00
1.30E+00
2.30E+00
3.60E+00
2.00E+00
1.80E*00
6.70E+00
8.60E-01
9.20E-01
1.70E-02
2.80E*00
1.70E-02
3.10E-02
3.70E-01
9.80E-01
llnorganics
1 Manganese
[ Vanadium
Normal
Normal
618E+02
342E»01
6.00E+02
328E+01
6.00E+02
3.28E+01
NOTES:
(a)  Based on the Shapiro-Wilk test results 'or EPS-1 and EPS-2 data.  See discussion in text
(b)  Calculated according to Supplemental Guidance to RAGS Calculating the Concentration Term, U.S. EPA. 1992,
    after averaging rounds and duplicates at each location.
(c)  Based on raw data prior to averaging the rounds and duplicates at each location.
(d)  Exposure Point Concentration is equal to the UCL unless the calculated UCL rs greater than the maximum detected
    concentration; then the maximum concentration was used.
(e)  Distribution testing for dioxins / furans was not performed due to the sample size. The value listed as the 95% UCL
    for dioxins / furans is the mean concentration.

-------
                                              TABLE 3
                Exposure Point Concentrations for Chemicals of Potential Concern in Soil (0-6")
                                Current Off-Site Residential Area (EPS 2}
Chemical
Organics
bis(2-Etfiy1hexy1)phthalate
DHvtoutytphthalate
Dioxins / furans (e)
(as 2,3,7,8 • TCOD equivalents)
Statistical
Distribution
of Data (a)

Lognormal
Lognormal
• • • •
95% UCL of
Mean Concentration
(mg/kg) (b)
Maximum
Concentration
(mg/kg) (c)
Exposure Point
Concentration
(mg/kg) (d)

3.25E-01
2.32E-01
446E-05
7.70E+00
1.60E-01
3.41E-04
3.25E-01
1.60E-01
4.46E-05
PAHs
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluorarrthene
Benzo{g.h,i)perylene
Benzo(k)fluoranthene
Chrysene
Dibenzo(a,h)anthracene
Fluoranthene
lndeno{ 1,2. 3-cdJpyrene
Pyrene
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
2.24E-01
2.60E-01
2.92E-01
2.90E-01
2.63E-01
2.81E-01
2.29E-01
2.52E-01
3.36E-01
2.33E-01
3.80E-01
2.20E+00
2.60E+00
8.10E+00
2.40E+00
3.30E*00
9.20E-01
1.40E+00
5.90E»00
1.20E+00
2.24E-01
2.60E-01
2.92E-01
2.90E-01
2.63E-01
2.81 E-01
2.29E-01
2.52E-01
3.36E-01
2.33E-01
NOTES:
(a)  Based on the Shapiro-Wilk test results for EPS-1 and EPS-2 data. See discussion in text
(b)  Calculated according to Supplemental Guidance to RAGS: Calculating the Concentration Term. U.S. EPA. 1992;
    alter averaging rounds and duplicates at each location.
(c)  Based on raw data prior to averaging the rounds and duplicates at each location.
(d)  Exposure Point Concentration is equal to the UCL unless the calculated UCL is greater than the maximum detected
    concentration; then the maximum concentration was used.
(e)  Distribution testing for dioxins / furans was not performed due to the sample size. The value Gsted as the 95% UCL
    for dioxins / furans is (he mean concentration.

-------
                                               TABLE 4
                Exposure Point Concentrations for Chemicals of Potential Concern in Soil (0-24*)
                                 Current Off-Site Residential Area (EPS 3)
1 Chemical
Organic*
bis(2-EthylH«yl)phtnalate
Carbazob
Diethylphthalate
Di-n-toutylphtnalatB
2.6-Dirvtrotoluene
Dwv-octylpnthalate
Statistical
Distribution
of Data (a)

Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
95% UCL Of
Mean Concentration
(mg/kg) (b)

2.47E-01
3.90E-01
3.28E-01
5.1BE-01
3.18E-01
3.14E-01
Maximum
Concentration
(mg/kg)(c)

1.10E400
1.30E-01
4.20E-01
4.80E-02
2.50E-02
6.30E-02
Exposure Point
Concentration
(mgrtig) (d)

2.47E-01
1.30E-01
328E-01
4.80E-02
2.50E-02
6.30E-02
PAHs
Acenaprrthytene
Anthracene
IBenzofalanthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(g,h.i)perylene
Benzo(k)fluoranthene
Chrysene
Oibenzo(a,hjanthracene
Fluoranlhene
Fluor one
|lndeno(1 ,2,3-cd}pyrene
Pentachlorophenol
Phenanthrene
Phonol
Pyrene
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormai
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Lognormal
Inorganics
Aluminum
Arsenic
Barium
Beryllium
Chromium
Cobalt
Copper
Lead
Nickel
Silver
Vanadium
Zinc
Lognormal
Lognormal
Lognormal
Normal
Normal
Lognormal
Normal
lognormal
Lognormal
Lognormal
Normal
Lognormal
4.36E-01
3.24E-01
4.66E-01
7.38E-01
1.55E*00
1.69E401
4.11E-01
6.98E-01
3.64E-01
4.76E-01
318E-01
1.76E+00
9.28E-01
3.47E-01
4.03E-01
1.34E+00

2.90E+O4
847£«00
5.32E*02
190E+00
323E+01
1.42E*01
2.39E«01
325E+01
305E+01
5.78E-01
499E+01
858EKJ1
9.80E-02
6.20E-01
1.40E+00
2.80E+00
5.10E-KW
4.60E-KX)
2.00E+00
2.50E+00
130E-KX)
1.30E+00
S.30E-02
460E+00
2.80E-01
1.60E-01
1.00E+00
1.70E+00
9.80E-02
3.24E-01
4.66E-01
7.38E-O1
1.55E-KX)
4.60E-KX)
4.11E-01
6.98E-01
3.64E-01
4.76E-01
530E-02
1.76E-KX)
2.80E-01
1 60E-01
4.03E-01
1.34E*00

3.28E+O4
1.19E+01
1.S8E*03
2.40E+00
4.08E+01
1.55E+01
3.17E+01
7.19E«01
3.29E«01
1.10E+00
6.77E+01
1.38E+02
2.90E+04
8.47E*00
5.32E+02
1.90E*00
3.23E+01
1.42E*01
2.39E-K)!
3.25E+01
3.05E+01
5.78E-01
4.99E+01
8.58E+01
NOTES:
(a)   Based on the Shapiro-Wilk test results for EPS-1 and EPS-2 data. See discxesion in text
(b)   Cak^Mateda, U.S. EPA, 1992;
     after averaging rounds and duplicates at each location.
(c)   Based on raw data prior to averaging the rounds and duplicates at each location.
(d)   Exposure Point Concentration is equal to the UCL unless the calculated UCL is greater than the maximum detected
     conceoti alien; then the maximum concentration was used.

-------
 week, year-round exposure to the ditches. The residents were assumed to be exposed to ditch
 sediment for one hour per exposure event.  These estimates for the exposure frequency and
 exposure time account for higher potential exposures during warmer months and lower potential
 exposures during colder months.

 EPS 2 • Exposure to Soil in Residential Areas Further from the Plant

 For ESP 2, the residential and non-residential areas more distant from the northern, western,
 southern, and eastern boundaries of the plant, EPA evaluated the risk from soil under an RME
 scenario and under a CTE scenario.  For the RME scenario, EPA evaluated the risk to a current
 resident (child and adult). For the CTE scenario, EPA evaluated the risk to a five- to 13-year-old
 current resident. The soil sampling locations included in the risk assessment for EPS 2 are
 shown on Figures 5 and 6.  The current resident scenario evaluated for EPS 2 represents the
 residents living in the areas distant from the plant boundaries (primarily to the north and
 northeast of the plant). In EPS 2, trie current residents were assumed to be exposed to soil
 utilizing the same exposure duration assumptions as EPS 1.

 Future Use Scenario
 EPS 3 - Exposure to Soil in Non-Residential Areas (Northeast of the Plant)

 For the EPS 3 risk analysis, it was assumed that the non-residential areas northeast of the plant
 (distant from the plant boundaries) will be used for residential purposes  in the future.  The risk
 analysis for EPS 3 evaluated the risk to hypothetical future residents.  EPA evaluated the risk
 from soil under an RME scenario and under a CTE scenario. For the RME  scenario, EPA
 evaluated the risk to a hypothetical current resident (child and adult). For the CTE scenario, EPA
 evaluated the risk to a hypothetical five- to 13-year-old current resident. The soil sampling
 locations included in the risk assessment for EPS 3 are shown on Figures 5 and 6.  In EPS  3, the
 future residents were assumed to be exposed to soil utilizing the same exposure duration
 assumptions as EPS 1 and EPS 2. If the area remains non-residential, then human exposure
 would be less than the assumed residential scenario.

 Human Health Toxicity Assessment
Toxicity factors are values that represent a COPC's dose-response relationship that is used in :isk
assessments.  The dose-response relationship quantifies the amount of a COPC received and the
corresponding incidence of adverse health effects. The most common toxicity factor values used
 in risk assessments are reference doses (for noncarcinogenic effects) and slope factors (for
carcinogenic effects). Toxicity factors for carcinogenic and noncarcinogenic effects of the
 COPCs were obtained from the Integrated Risk Information System (IRIS) and the Health Effects
 Assessment Summary Tables (HEAST), with a few exceptions based on alternate EPA guidance.
 Lead toxicity factors are not available, and therefore blood lead levels were predicted for children
 using the Integrated Exposure Uptake Biokinetic (IEUBK) model.
Lincoln Creosote Site
Record of Decision
Page 21

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                                          Table 5
                            Potential Exposure Pathways/Routes
Exposure
Pathway
EPS1
Soil (0-6")



f
Soil (0-24")



Sediment (Drainage
ways)


EPS 2
Soil (0-6")




Soil (0-24")



EPS 3
Soil (0-24")





Scenario


Current Use



Current Use



Current Use





Current Use



Current Use




Future Use





Receptor


RME - Child and adult
residents
CTE- 5- 13 year old
resident

RME -Child and adult
residents
CTE -5- 13 year old
resident
RME - Child and adult
residents
CTE -5- 13 year old
resident

RME - Child and adult
residents
CTE -5- 13 year old
resident

RME - Child and adult
residents
CTE -5- 13 year old "
resident
RME - Child and adult
residents
CTE -5- 13 year old
resident


Exposure
Routes

* Incidental .ingestion
- Dermal contact
- Inhalation of
windblown dust

- Ingestion of
homegrown produce


- Incidental ingestion
- Dermal contact



- Incidental ingestion
- Dermal contact
- Inhalation of
windblown dust

- Ingestion of
homegrown produce


- Incidental ingestion
- Dermal contact
- Inhalation of
windblown dust
- Ingestion of
homegrown produce
Lincoln Creosote Site
Record of Decision
Page 22

-------
 In predicting potential human health risks, both carcinogenic and noncarcinogenic health effects of
 a COPC must be considered. When considering carcinogenic effects, EPA considered only the effects
 pf those substances shown to cause cancer in animals and/or humans.  The EPA categorization of
 carcinogens is shown in Table 6. Excessive exposure to certain COPCs classified as both carcinogens
 and noncarcinogens, can produce adverse noncarcinogenic effects as well as carcinogenic effects.
 Therefore, cancer slope factors (CSFs) were developed for those COPCs classified as carcinogens,
 and reference doses (RfDs) are developed to express the noncancer toxic effects for all COPCs. A
 reference dose is an estimate of a daily exposure level for the human population, including sensitive
 subpopulations (e.g.. children and pregnant women), that is likely to be without an appreciable risk
 of deleterious effects during a lifetime. The CSFs and the RfDs for the  COPCs are presented in
 Tables 7 and 8.

 Human Health Risk Characterization

 Carcinogenic Risk
 Table 9 presents a summary of the estimated carcinogenic risks posed by the COPCs on the Site. The
 risks are listed by exposure pathway and scenario for the current and hypothetical future residents.
 Ingestion and inhalation exposure routes are included in the risk summation. The actual carcinogenic
 risk  may be zero, or the actual risk may be some value which lies between zero and the estimates
 summarized in Table 9.

 Each person living in the United States has a lifetime cancer risk of between one in three and one in
 four.   The risks posed by the COPCs on the Site, as described in Table 9, are additional risks that
 are posed by the neighborhood portion of the  Site now that it has been cleaned up by Joslyn under
 EPA oversight.  That is, the risks listed in Table 9 are lifetime cancer risks, posed by  the COPCs on
 the Site (not including the plant), over and above the cancer risk that each U.S. resident faces. These
 risks, calculated for the Site (not including the plant) are generally referred to in this ROD as "excess"
 lifetime cancer risks because they are risks which are in addition to the lifetime cancer risk posed to
 the members of the U.S. population in general.    All risk estimates in Table 9 for all exposure
 scenarios are within the risk range of one in ten thousand to one in one million excess lifetime cancer
 risk that may be acceptable under the NCP.  These risks are probabilities that are generally expressed
 in scientific notation. In scientific notation, 1E-04 means one in ten thousand,  IE-OS means one in
one hundred thousand, and 1E-06 means one in one million.  An excess lifetime cancer risk of 1E-04
indicates that, as a reasonable maximum estimate, an individual has (in addition  to the cancer risk
which ever,  U.S. resident faces) a  1 in  10,000 chance of developing cancer as a result of location-
specific exposure to a carcinogen over a 70-year lifetime under specific exposure conditions at a given
site.  Table 10 identifies the COPCs on the neighborhood portion of the Site which  pose a greater
than  1E-06 excess lifetime cancer risk according to the exposure pathways and exposure routes in
 question. It should be noted that all risks which exceed 1E-06 are less than 1E-04, which places the
 risks within the  risk range that may be acceptable under the NCP.
Lincoln Creosote Site
Record of Decision
Page 23

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                                          Table 6
                    EPA and IARC Categorizations of Carcinogens
EPA Cateaorization of Carcinooens (EPA. 1 986a)
ANIMAL EVIDENCE
HUMAN EVIDENCE
Sufficient
Limited
Inadequate
No Data
No Evidence
Sufficient

A
B1
B2
B2
B2
Limited

A
B1
C
C
C
Inadequate

A
B1
D
D
D
No Data

A
B1
D
D
D
No Evidence

A
B1
0
E
E
Kav:

Group A

Group 61

Group B2


Group C

Group D

Group E
Human carcinogen (sufficient evidence from epkjemiological studies).

Probable human carcinogen (at least limited evidence of carcinogenitity to humans).

Probable human carcinogen (a combination of sufficient evidence in animals and inadequate
data in humans).

Possible human carcinogen (limited evidence in animals in the absence of human data).

Not classified (inadequate animal and human data).

No evidence for carcinogenicity (no evidence for carcinogenicrty in at least two adequate
animals tests in different species, or in both epidemiological and animal studies).

-------
                                                     Table 7
                              Carcinogenicity Classifications and Route-Specific
                                  Cancer Slope Factors (CSFs) (mg/kg-day)'
Ckoueal
6&JWKS . .v, ;i'<:
IButf-edrylhe^Dpothalate
Burybenzyl phthalate
Carbazole .
2 ,6-Dinitrotoluene
Dioxins/Furani
Hexachlorobenzene
>Aft
Benzo[a]anthraceneb
Benzo[a|pyrene
Benzo[b]fluoranlhenel>
BenzoMfhiorantbeoe
ChryMoe"
Dibeoi[«,b|«nthr»ceoek
Indeoo (l,2,3-cd)pyreneb
Peatachloropbenol
INORGANICS
Arsenic
Beryllhim
ChfXMnium VI
Lead
Nickel(refinery dust)
.EPA
CttPOMConoty
flurifirAtBOB


B2
C
B2
B2
B2
B2

B2
B2
B2
B2
B2
B2
B2
B2

A
B2
A
B2
A
Oral
CSF

1.4E-02
NTV
2E-02
6.8E-01
1.5E+05
1.6E+00

7.3E-01
7.3E+00
7.3E-01
7.3E-02
7.3E-03
7.3E+00
7.3E-01
1.2E-01

1.8E+00
4.3E-KX)
NC
NTV
NC
Rrfertnc*

EPA, 1994a
_
EPA, I994b
EPA, 1994*
EPA, 1994.
EPA, 1994*

EPA, 1992
EPA, 1994a
EPA, 1992
EPA. 1992
EPA, 1992
EPA, 1992
EPA, 1992
EPA, 1994a

EPA, I994a
EPA, I994a
_
_
-
InhalatiM
CSF

NTV
NTV
NTV
NTV
1.5E+05
1.6E+00
• • ;'. •:•''••>
NTV
NTV
NTV
NTV
NTV
NTV
NTV
NTV

1.5E+01
8.4E+00
4.1E+01
NTV
8.4E-01
RcferaKe

„
r
ul
_
EPA, 1994.
EPA, 1994b

__
__
_
	
	
_
__
_

EPA, 1994«
EPA, 1994"
EPA, 1994'
_ .
EPA, 1994'
DcruuT
CSF

1.4E-02
NTV
2E-02
6.8E-01
1.5E+05
1.6E+00

NTV
NTV
NTV
NTV
NTV
NTV
NTV
1.2E-01

6E+00
1.4E+01
NC
NTV
NC
'  The dermal slope factor was obtained by dividing the oral slope factor by the GI absorption factor:  organics (1.0); inorganics (0.3)
  according to EPA Region VI (WESTON, 1994).

k  The oral slope factors are for benzo[a)pyrene adjusted for the equivalent toxicities as recommended by EPA Region VI (EPA, 1992;
  WESTON. 1994). Refer to '-xt in Section 4 for TEF values.
NC  = Not a carcinogen by mi* exposure route.
NTV = Slope factor not available through IRIS or HEAST.

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                  Table 8
Reference Doses (RfDs) and Toxicity Endpoints
                (mg/kg-day)
Chemicals
ORGANICS
Bii(2-ethylhexyl)ph«halate
Butylbearvlpbthalate
Carbazole
Dibenzofunn
DiethvDhthalate
Di-n-bulylphthalale
2,6-Dinitrotohiene
Di-n-octylphthalate
Dioxins/Furans
Hexachlorobenzene
2-Methyln*phthalene
Naphthalene
fAHS
Aceoaphthene
AcenaDhthylene
Anthncene
Benzolalanthracene
Benzolblfluoranthene
Renzolalnvrene 	 	
OralRfD

2E-02
2E-O1
NTV
NTV
8E-O1
1E-OI
1E-O3
NTV
NTV
8.4E-04
NTV
NTV

6E-02
NTV
3E-01
NTV
NTV
NTV
Reference

EPA, 1994a
EPA, 1994«
--
—
EPA, 1994*
EPA. I994a
EPA, 1994b
--
--
EPA. 1994a
--
--

EPA, 1994*
--
EPA, 1994a
--
--
--
==«===
Inhalation
RH>

NE
2E-01
NTV
NTV
8E-01
1E-01
1E-01
NTV
NTV
8.4E-04
NTV
NTV

6E-02
NTV
3E-01
NTV
NTV
NTV
:^^^=^^!^^fa-i- i TTTW
Reference

—
Ic
„
..
(0
(c)
(c)
..
..
EPA, 1994b
—
..

(c)
-
(0
—
--
-•
»«==
DermaT
RfD

2E-02
2E-01
NTV

8E-01
1E-01
1E-03
NTV
NTV
8.4E-04
NTV
NTV

6E-02
NTV
3E-01
NTV
NTV
NTV
====*™"*^^^"™^^™^=^^^^^^=««>=«««^^^«i
Toxicity Endpointk
	 _ 	
	 • 	 	 	
Increased liver weieht
Liver effect*
NA
NA
Decreased growth/weight
Increased mortality 	
Increased mortality; neurdojucity;
methemoglobinemia; bile duct hypeml««i«
NA
NA
Liver effects
NA
NA


NA
No effects
NA
NA
NA

-------
                  Table 8
Reference Doses (RfDs) and Toxicity Endpoints
                (Continued)
Chemicals
Benzofe.h.iloerylene
Benzofklfluormnthene
Chmene 	
Dibenz[«.hl«nthracene
Fluorantbene
Fluorene 	
tndeno(1.2.3-cd)pyrene
Phenanthrene
Pyretic 	
Pentachlorophenol 	
Phenol 	
INORGANICS
Aluminum 	
Antimonyfpentoxide) 	 . —
Arsenic 	 	
Barn"" 	

rhrnmmm HI 	 .


P j 	 	 	
OralRfD
NTV
NTV
NTV
NTV
4E-02
4E-02
NTV
NTV
3E-02
3E-02
6E-01

NTV
5E-04
3E-04
7E-02
5E-03
1E+00
5E-03
NTV
3.7E-02
Reference
—
-
..
..
EPA, 1994 A
EPA, 1994a
—
--
EPA, 1994a
EPA, 1994 A
EPA, 1994a

--
EPA, 1994a
EPA. 1994a
EPA, 1994a
EPA, 1994«
EPA, 1994a
EPA, 1994a
„
EPA, I994h
Inhalnlinn
RfD
NTV
NTV
NTV
NTV
4E-02
4E-02
NTV
NTV
3E-02
3E-02
6E-01

NTV
5E-04
3E-04
7E-02 _,
5E-03
1E+00
5E-03
NTV
3.7E-02
Reference
_
-
_
-
(0
(0
-
-
(0
(0
0

--
(0
(0
w
EPA, 1994b
(0
EPA, 1994b

W
Dermal*
RfD
NTV
NTV
NTV
NTV
4E-02(1)
4E-02
NTV
NTV
3E-02
3E-02
6E-01

NTV
1.5E-04
9E-05
2.1E-01
1.5E-03
3E-01
1.5E-03
NTV
1.1E-02
Toricity Endpoint"
NA
NA
NA
NA
Nephropathy; increased liver weight
HemoKlobinemia
NA
NA
Nephropathy
Fetotoxicity
Decreased fetal body weight

NA
Decreased longevity
Keratosis; hyperpigmentation
Hypertension, fetotoxicity
No effects
No effect*
No effects
NA
Gastrointestinnl irritation

-------
                                                                    Table 8
                                             Reference Doses (RfDs) and Toxicity Endpoints
                                                                 (Continued)
Chemicals
Lead*
Manganese (food)
Mercury
Nickel (soluble salt)
Selenium
Silver
Thallium (sulfate)
Vanadium
Zinc
OralRfD
N1V
1.4E-O1
3E-04
2E-02
5E-03
5E-03
8E-OS
9E-03
3E-01
Reference
...
EPA, 1994.
EPA, 1994b
EPA, 1994*
EPA, 1994*
EPA, I994a
EPA, 1994.
EPA, 1994a
EPA, 1994a
=^=^^™=
Inhalation
RfD 1
NTV
1.4E-01
3E-04
2E-02
5E-03
SE-03
8E-05
9E-03
3E-01
KmHKOEBEBBS:
Reference
--
(0
(0
CO
(0
(0
M
(c)
	 (*)
t^^^m^m^m^m
DermaT
RfD
NTV
4.2E-02
9E-05
6E-03
1.5E-03
1.5E-03
2.4E-05
2.7E-03
9E-02
•
Toxicity Endpoint*
?993? 1°"d ** Child (EPAl 1W4c: AT^DR-
Central nervous system effects



Argyria
Increased SOOT, LDH 	 	
Decreased hair cystine

• The dermal reference dose was obtained b> n uliiplying the oral reference dose by the GI absorption factor:  organics (1.0); inorganics (0 3)- according to EPA Refiion
  VI (WESTON, 1994).                                                                                                      '         B          *

" The toxiciry endpoint is the critical toxic effect which serves as the basis for the development of the RfD (EPA, 1989).

• For volatile organics or compounds inhaled through the dust pathway, EPA Region VI recommends that the oral reference dose be used for the inhalation reference dose
  (route-to-rout* extrapolation) if the latter is unavailable through IRIS or HEAST (Personal Communication, 1994; EPA, 1989).

d The reference dose for copper was based on the MCL of 1.3 mg/L.  This is not a true reference dose. Uncertainty for the calculated copper hazard index is discussed
  in Section 6.

* Refer to Section S for evaluation of blood lead using IEUBK model (EPA, 1994c).

NE  - Not evaluated.

NTV = No toxiciry vahies available from IRIS or HEAST.

NA =  Mot applicable

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                                             Table 9
                                  Summary of Carcinogenic Risks
                                 Ingestion and Inhalation Pathways
Exposure Pathway
iPS 1 - Current Exposure
to Soil and Sediment
EPS 2 - Current Exposure
to SoU
:PS 3 - Future Exposure
to Soil
Scenario
RME
CTE
RME
CTE
RME
CTE
Receptor
Adult Resident
5- 13 year old Resident
Adult Resident
5-13 year old Resident
Adult Resident
5-13 year old Resident
Total Carcinogenic Risk
Through All Chemicals <§> Sum of risk for soil ingestion, sediment ingestion, and dust inhalation pathways.
   Risk for dioxins/furans is summarized separately.
(b)
   A risk between 1E-06 and 1E-04 is within the EPA-defined acceptable risk range.

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  EPS1

 A total excess lifetime carcinogenic risk of 3.37E-05 was calculated for the current adult resident
 (RME scenario) living in study zone EPS 1. Approximately 78% of the risk was due to ingestion
 of soil, with the largest proportion of the risk contributed by arsenic (50%) and benzo(a)pyrene
 (24%). The risk for dioxins/furans (6.27E-05) was estimated separately from the other COPCs due
 to the limited data set (only two samples).

 A total excess lifetime carcinogenic risk of 1.08E-05 was calculated for the five- to 13-year-old
 resident (CTE scenario) living in study zone EPS 1. The exposure pathways and COPCs which
 contributed the greatest proportion of risk were identical to the RME scenario.  Arsenic and benzo(a)
 pyrene contributed 74% of the total carcinogenic risk. The risk for dioxins/furans was estimated to
 be2.01E-05.

 EPS 2

 A total excess lifetime carcinogenic risk of 6.60E-06 was calculated for the current adult resident
 (RME scenario) living in study zone EPS 2. Carcinogenic risks were due entirely to soil ingestion,
 with 85% of the risk  contributed approximately equally by two PAHs,  benzo(a)pyrene and
 dibenz(a,h)anthracene.  The risk for dioxins/furans was estimated to be  1.09E-05.

 A total excess lifetime carcinogenic risk of 2.12E-06 was calculated for the five- to thirteen-year-old
 resident (CTE scenario) living in study zone EPS 2.  Carcinogenic risks were due entirely to soil
 ingestion, with 85% of the risk contributed by the two  PAHs  identified  above.  The risk for
 dioxins/furans was estimated to be 3.49E-06.

 EPS 3

 A total excess lifetime carcinogenic  risk of 4.97E-05 was calculated for the future adult resident
(RME scenario) in study zone EPS 2. Carcinogenic risks were due entirely to soil ingestion, with
approximately 66% of the risk contributed by arsenic and beryllium. These two COPCs are naturally
occurring inorganics, and the estimated risk represents the sum of background and incremental Site-
related risk (if any).

A total excess lifetime carcinogenic risk of 1.59E-05 was calculated for the  five- to 13-year-old
resident (CTE scenario) in study zone EPS 3. Carcinogenic risks were due entirely to soil ingestion,
with approximately 66% of the risk contributed by arsenic and beryllium.

Noncarcinogenic Risk

Table 11 presents a summary of the estimated noncarcinogenic risks due to ingestion and inhalation
exposure routes by scenario for the current and hypothetical future residents.  The hazard quotients
 and  indices have been calculated separately for  the child and adult residents in EPS 1, 2 and 3
 scenarios. All exposure scenarios resulted in hazard indices less than 1, which is the acceptable level
 defined by EPA.

 Lincoln Creosote Site
 Record of Decision
 Page 30

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                       Table 10
Summary of Chemicals Exceeding Carcinogenic Risk of 1E-06
     Ingestion of Soil and Sediment and Inhaltion of Soil
Exposure Pathway
EPS 1 - Current Exposure
to Soil and Sed .lent

EPS 2 - Current Exposure
to Soil

EPS 3 - Future Exposure
to Soil
	 '
Scenario
RME
CTE
RME
CTE
RME
CTE
-. i
Receptor
Adult Resident
5- 13 year old Resident
Adult Resident
5-13 year old Resident
Adult Resident
5-13 year old Resident

Ingestion of Soil
Dioxins / furans 6.20E-05
Benzo(a)pyrene 4 I8E-06
Benzo(b)fluoranthene 1. 01 E-06
Dibenzo(a,h Anthracene 3.03E-06
Arsenic 1 68E-05
Dioxins / furans I.99E-05
Benzo(a)pyTene I.34E-06
Arsenic 5.40E-06
Dioxins / furans 1 09E-05
Benzo(a)pyrene 2.97E-06
Dioxins / furans 3.49E-06
Benzo(a)pyrene 8.44E-06
Benzo(b)fluuranthene 1.78E-06
Dibenzo(«,h)anthracene 4.17E-06
Indeno(1.2.3-cd)pyrene 2.01 E-06
Arsenic 1 .99E-05
Beryllium 1 28E-05
Benzo(a)pyrene 2.71 E-06
Dibenzo(a,h)anthracene 1.34 E-06
Arsenic 6.38E-06
Beryllium 4.10E-06

Ingestion of Sediment
Benzo(a)pyrene 3.9 1 E-06
Dibenzo(a,h)anthracene 1 .46E-06
Benzo(a)pyrene 1.25E-06
NA
NA
NA
NA
Inhalation of Soil
NA
NA
NA
NA
NA
NA


-------
          Table 11
   Summary of Hazard Indices
Ingestion and Inhalation Pathways
Exposure Pathway
EPS 1 - Current Exposure
to Soil and Sediment

EPS 2 - Current Exposure
to Soil

:PS 3 - Future Exposure
to Soil

Scenario
RME
CTE
RME
CTE
RME
CTE
Receptor
Child Resident
Adult Resident
S-13 year old Resident
Child Resident
Adult Resident
S-13 year old Resident
Child Resident
Adult Resident
S-13 year old Resident
Total Hazard Index
Through Chemicals
and Exposure Routes
7.38E-01
2.15E-01
2.30E-01
4.08E-04
1.17E-04
1.25E-04
9.74E-01
2.81E-01
2.65E-01

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 Evaluation of Lead Taxicity

 Using the IEUBK model, the estimated blood lead levels in children residing near the Lincoln
 Creosote She is 1.9 Mg/dL, which is five fold lower than the critical blood level of 10 ug/dL identified
 by EPA and the Centers for Disease Control.  This estimate was calculated under conservative
 conditions such that the 1.9 ug/dL value represents an overestimation.  Based on these observations
 lead does not pose a significant human health risk in the residential areas (or in areas that may be used
 as residential areas in the future) on the Site.  The soil lead level of 32.5 milligrams per kilogram
 (mg/kg) used as an input into this calculation is approximately 12 times lower than the currently
 recognized soil lead screening level for residential properties of 400 mg/kg.

 Human Health Uncertainty Analysis
 Risk assessment uncertainties were evaluated in the data evaluation, exposure assessment and toxicity
 assessment sections of the Risk Assessment. In addition, quantitative risk estimates are presented for
 ingestion of homegrown produce and for dermal contact with soil and sediment. Risk estimates for
 these exposure routes are  included in the Uncertainty Analysis because of the high uncertainty
 associated  with intake and toxicity factor estimates.  It was  concluded that risk estimates were
 conservatively derived and are overestimated based on integration of all the uncertainties.

 The following summary provides a brief statement of some of the factors or assumptions employed
 in the Risk Assessment.  Due to these conservative assumptions, it is very likely that the Risk
 Assessment overestimates the actual risk to Site residents.

 •      Portions of the exposure areas were excavated and backfilled.  However, samples used to
       analyze risk were not taken from the clean backfill, but only from undisturbed areas of the
       Site.  Including samples taken from  clean backfill would have lowered  the statistical
       calculation of the exposure point concentration, thus lowering the calculated risk.

•      Once  contaminated  areas were excavated, samples were taken to confirm that PAHs were
       cleaned up to target levels. However, post-excavation data are not available for inorganics,
       dioxins/furans, and  other organic constituents.  Including samples taken from the post-
       excavation areas would have lowered the statistical  calculation of the exposure point
       concentration, thus lowering the calculated risk.

•      When concentrations of COPCs were below the detection limits of the instruments used to
       analyze samples, it was assumed that the concentration in the sample in question was one half
       the detection limit, when in fact there could have been no COPCs present. This assumption
       was applied to each dioxin/furan congener as well. This may result in an overestimation of
       risk.

 •      EPA treated possible carcinogens as if they were probable carcinogens for the purpose of this
       Risk Assessment. Therefore, if any of the possible carcinogens are not in fact carcinogens,
       the risk has been overestimated.
Lincoln Creosote Site
Record of Decision  .
Page 33

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 Conclusions - Human Health Risk Assessment
 Remediation goals are  COPC concentrations that EPA establishes as a cleanup standard  for
 contaminated media such as soil or sediment. Remediation goals establish acceptable exposure
 levels that are protective or human health and the environment and are developed by considering
 ARARs which are "applicable requirements" or "relevant and appropriate requirements" as those
 terms are defined at 40 CFR § 300.5 and 42 U.S.C. Section 962 l(d ).  Where ARARs are not
 available for carcinogenic COPCs, as in the case of the COPCs found at the Site, EPA selects
 remediation goals that represent an excess upper bound life-time cancer risk to an individual of
 between 1E-04 and 1E-06. EPA uses 1E-06 as a point of departure which means that a cumulative
 risk level of 1 E-06 is used as the starting point (or initial "protectiveness" goal) for determining the
 most appropriate risk level that the cleanup alternatives considered for the site in question should
 be designed to attain. However factors related to exposure uncertainty and technical limitations may
justify a modification of the remediation goal as long as the goal falls within the range of 1E-04 to
 1E-06.

The carcinogenic risks for the Lincoln Site exceed 1 E-06; however, EPA has determined that certain
factors present at the Site warrant leaving the Site as is with no further remedial action to be taken.
Specifically,  background concentrations of PAHs at the Site are  such that  the background
concentrations of PAHs alone would result in an excess lifetime cancer risk of 1  E-06. Therefore,
it is technically impracticable for EPA to attain a remediation goal of 1 E-06 at the Site. Moreover,
the Site risk as calculated is also consistent with previous PAH cleanup goals utilized in EPA
Region 6.

The carcinogenic risks for dioxins/furans were estimated separately from the other COPCs, and were
not included in the summation of risk because of the limited data set. The calculated excess lifetime
cancer risk for dioxin exceed 1 E-06; however, EPA has determined that no further action is required
due to the amount of uncertainty present in the risk assessment.  Several conservative procedures and
assumptions were incorporated in the risk assessment for dioxins.

The data that was used to derive the risk is limited based on the small number of data points
available to characterize exposure (in some cases only two data points were used), and the lack of
post-removal data.  The small  number of samples and the lack of post-removal data will bias the
exposure concentration high and result in a conservative estimate of risk.

The dioxin risk was calculated using all the various forms of dioxins (or congeners). The risk from
the congeners were estimated using a 2,3,7,8 TCDD equivalent, similar to the method used for the
BAP equivalent used at the Site. 2,3,7,8 TCDD is the most toxic of the dioxins, however, it was not
detected in any of the samples at the Site.  The risk assessment assumed that all the congeners of
dioxin were present  in every  sample if they were detected in any sample. This conservative
assumption was  pronounced in EPS1 which had the highest calculated dioxin risk.   Several
congeners of dioxin (the most potent) were assumed to be present in EPS1 which were not detected
in any  samples  in EPS1.  The conservative treatment of the dioxin data may result  in an

Lincoln Creosote Site
Record of Decision
Page 34

-------
 overestimation of risk. Moreover, all detections of dioxins/rurans in soil and sediment were less than
 the 1 ng/kg (ppb) cleanup level used by EPA in some Records of Decision for residential sites.

 The methodology used to evaluate noncarcinogenic risk, unlike the methodology used to evaluate
 carcinogenic risk, is not a measure of risk probability. For noncarcinogenic toxic risk EPA uses the
 Hazard Index (HI) concept. If an HI exceeds unity (i.e.. exceeds one), there might be a potential for
 noncarcinogenic health effects occurring under the defined exposure conditions. For the Site, the
 total hazard indices for all the receptors and exposure pathways evaluated in EPS 1, EPS 2 and EPS
 3 were lower than one for both the RME and CTE scenarios. Therefore, EPA has determined that
 there is no significant noncarcinogenic toxic risk to human health at the Site.

 Ecological Risk Assessment
 Complete exposure pathways were not identified for ecological receptors due to the remediation of
 the plant and the Site neighborhood areas, the urbanization of the study area and the intermittent
 nature of the drainage pathways. A suitable habitat for ecological receptors is not present within the
 Site; therefore, it is believed that the occurrence of ecological species and subsequent exposures and
 risks to Site-related constituents are insignificant.

 DESCRIPTION OF THE SELECTED REMEDY - NO FURTHER ACTION

 EPA considers a no further action alternative when the site poses no current or potential threat to
 human health or the environment or when a previous response action eliminated the need for further
 remedial.response.

 At the Lincoln Creosote Site, previous removal actions eliminated existing and potential threats to
 human health or  the environment. The Risk Assessment documents that the removal actions taken
 on the Site eliminated the need for further response action, and that the Site poses no current or
 potential threat to human health or the environment. Accordingly, EPA has selected no further
remedial action at the Lincoln Creosote Site.

The no further action remedy does not include any element of future work such as maintenance or
monitoring, engineering controls, or institutional controls. Unlimited Site access can occur without
unacceptable exposure to hazardous substances.
Lincoln Creosote Site
Record of Decision
Page 35

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                            LINCOLN CREOSOTE SUE
                            BOSSIER CITY, LOUISIANA
                              RECORD OF DECISION
                           RESPONSIVENESS SUMMARY

 This Responsiveness Summary is prepared from oral comments received during the public
 comment period on the Proposed Plan.  The comment period ran fiom September 18, 1997,
 through October 17,1997. No written comment letters were received.

 A public meeting was held on September 29, 1997, at the Bossier City Municipal Complex.
 Approximately 20 people attended the meeting.  Approximately eleven people provided comment
 during the meeting. A transcript of the meeting was prepared and is part of the Administrative
 Record. A review of the transcript revealed one comment that was not fully addressed during the
 public meeting.

 PUBLIC COMMENT

      Where were background samples collected and evaluated as part of the ESI/RI and what
      levels of polynuclear aromatic hydrocarbons were found?

EPA RESPONSE

      In an effort to evaluate the background level of polynuclear aromatic hydrocarbons (PAH)
      occurring in the soils of the study area for the Lincoln site, EPA collected 69 background
      soil samples from 6-inch depth intervals ranging from 0 to 2 feet at 20 locations.  The
      background samples were collected in areas where impacts attributable to a release from
      the Lincoln Creosote site were not suspected to occur. The sample locations are identified
      in the ESI/RI (Figure 4-1) but are generally located in the residential areas to the north
      anJ west.

      Several PAH compounds found in the background samples that were also found at the
      Lincoln Creosote site include:

                          anthracene               4 ug/kg
                          benzo(a)anthracene    42.3 ug/kg
                          benzo(a)pyrene        46.3 ug/kg
                          benzo(b)fluoranthene     7.1 ug/kg
                          benzo(g,h,i)perylene    273.2 ug/kg
                          benzo(k)fluoranthene   37.7 ug/kg
                          chrysene              51.9 ug/kg
                          fluoranthene          116.3 ug/kg
                          indeno( 1,2,3-cd)pyrene    19 ug/kg
                           phenanthrene          67.3 ug/kg
                           pyrene               92.3 ug/kg

      Section 6 of the ESI/RI contains additional information concerning the background
      investigation.

-------