EPA  Superfund
       Record of Decision:
                                 PB96-964204
                                 EPA/ROD/R06-96/102
                                 March 1997
       Vertac Superfund Site,
       Operable Unit 2, Jacksonville, AR
       9/17/1996

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           RECORD OF LECISION
      VERTAC SUPERFUND SITE
        JACKSONVILLE, ARKANSAS
             OPERABLE UNIT #2
SOILS, FOUNDATIONS AND UNDERGROUND UTILITIES
  UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
              SEPTEMBER 1996

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                  RECORD OF DECISION
              CONCURRENCE DOCUMENTATION
                       FOR  THE
                VERTAC SUPERFUND SITE
                   OPERABLE UNIT  #2
                JACKSONVILLE,  ARKANSAS
                Philip H.  Allen,  P.E.
            Site Remedial  Project Manager
                    John Dugdale
              Senior Attorney,  6SF-DL
                Wren Stefager, CHuef
         Arkansas/Oklahoma Section,  6SF-AO
              Wilfianf K.  Honker,  Chief
          Superfund AR/OK/TX Branch,  6SF-A
                 Mark Peyck^  Chief
Superfund Litigation and Enforcement Branch, 6SF-DL
             .                          	
       -  Myron Of Knudson,  P.E.,  Director
              Superfund Division, 6SF

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                            DECLARATION
                       VERTAC  SUPERFUND SITE
                        RECORD OF DECISION
                         OPERABLE UNIT #2
                          SEPTEMBER 1996   >

 SITE  NAME  AND  LOCATION

 Vertac  Incorporated
 Jacksonville,  Arkansas

 STATEMENT  OF BASIS AND PURPOSE

      This  decision document presents the selected remedial action
 for Operable Unit 2, Soils, Foundations and Underground
 Utilities, for the Vertac Incorporated site (the site),  located
 in Jacksonville, Arkansas, whic"  was chosen in accordance with
 the Comprehensive Environmental Response, Compensation and
 Liability Act  (CERCLA), 42 U.S.C. S 9601 et seq..  and, to the
 extent practicable, the National Oil and Hazardous Substances
 Pollution Contingency  Plan  (NCP), 40 CFR Part 300.  This decision
 is based on the administrative record file for this site.

     The State of Arkansas fully supports this remedy, and a
 concurrence letter from the Arkansas Department of Pollution
Control and Ecology (ADPC&E) can be found in Attachment C to this
Record of Decision (ROD).

ASSESSMENT OF THE SITE

     Actual or threatened releases of hazardous substances from
this site,  'f not addressed by implementing the response action
selected in this ROD, may present an imminent and substantial
endangerment to public health, welfare,  or the environment.

DESCRIPTION OF THE SELECTED REMEDY

     There are six operable units for the Vertac site.  This ROD
 for Operable Unit 2 (OU2) addresses the remediation of dioxin-
and herbicide-contaminated on-site soils and debris, of on-site
underground utilities, and of on-site building foundations and
curbs.  This ROD also  addresses the disposal of contiguous soils
and debris originally  addressed by the Vertac Superfund Site Off-
 Site Areas Record of Decision (ROD), dated September  27,  1990, in
which EPA had selected its preferred remedy for soils, sediments,
 and sludges excavated  or to be excavated from contiguous  areas
 adjacent to the site.  That 1990 Off-Site Areas ROD had  selected
 on-site incineration as the remedy for the soils  to be excavated
 from  the Rocky Branch  Creek floodplain,  the sediments removed
 from  sewage collection lines, and the sludges removed from the
 sewage digester.  Subsequent  to  executing the  1990 Off-Site Areas
 ROD,  EPA deferred addressing  the disposition of the 1990 Off-Site
 Areas ROD  media so that  its disposal would be  consistent with the
 disposal of similar media  addressed  in the RODs for OU1  and OU2.

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      Finally, in 1990 Hercules,  Inc.,  a party liable for site
 response actions and costs,  in 1990 had performed a removal
 action in which it excavated and bagged,  and then stored on-site,
 dioxin-contaminated soils excavated from contiguous residential
 areas.  The 1993 ROD for OU1 expressly deferred the disposition
 of those bagged soils until  EPA selected a remedy for OU2.   All
 of the media addressed in this ROD constitute low level  threat
 media, and the remedy selected takes into account the reasonably
 anticipated future land use  for  the site,  which is
 commercial/industrial.   A brief  description of the components of
 the OU2 remedy follows:

      On-Site Soils

      The remedy selected for OU2  consists  of  the  excavation and
 consolidation within an  on-site hazardous  waste landfill  that
 meets the substantive requirements <-f  Subtitle C  of the Resource
 Conservation and Recovery Act (RCRA),  42 U.S.C. S  6901 et seq..
 of  site soils and  debris that contain  dioxin  contamination  levels
 at  or above a 5  part per billion  (ppb) cleanup level.  Excavated
 areas will  be backfilled with clean  fill,  graded,  and vegetative
 cover will  be established.   Upon  completion of the site
 remediation,  data  indicate that the  average dioxin concentrations
 will  be  less  than  1  ppb.   This is  due  to the  fact that a  large
 percentage  of  the  site acreage contains dioxin levels well below
 1 ppb.

      The northern portion  of the site, which  is approximately 100
 acres, never had been used for industrial operations and the
 soils  are less than  1 ppb dioxin.  The northern portion of the
 site will be unrestricted  and will be available for
 commercial/industrial redevelopment.  The southern portion of the
 site, which consists of about 93 acres, is where active
 industrial activities had occurred and the highest concentrations
 of dioxin contamination are  found.   Some segments of the southern
portion of the site will remain fenced and access will ba
restricted to on-site maintenance workers where existing  landfill
areas exist, where the on-site hazardous waste  landfill will be
 located, where an active wastewater  treatment  plant is located,
and possibly where ground water extraction and containment wells
are likely to be situated  as part  of implementing the remedy  for
ground water.  EPA plans to  execute  the ROD for the ground water
operable unit  (OU3)  concurrently with the  execution of this ROD.

     Such restrictions on  the southern portion of  the site  are
necessary to prevent trespass  into and the disturbance of the
existing waste disposal  areas that were created as a result of  a
 1984  order  of the U.S. District Court  for  the Eastern District of
Arkansas, into the wastewater treatment plant,  into the hazardous
waste  landfill,  and  possibly around  any future ground water
wells.  The 1984 court order imposed the  "Vertac  Remedy," under
which the Vertac plant cooling water pond and the equalization
 basin were  closed  and sediments  from these units  were removed and
 placed into an excavated area where earlier operators had buried

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 drums of waste.  The burial area was capped,  a French drain and
 leachate collection system were installed around the burial
 areas,  and a wastewater treatment plant was constructed to treat
 water from the French drain and storm water runoff.   Ground water
 monitoring wells were also installed and a ground water
 monitoring program was initiated.

      Notwithstanding the limitations of the 1984  Court-ordered
 Vertac  Remedy,  the remedy selected herein provides a feasible
 means of ensuring that the greatest amount of site acreage be
 ~eturned to commercial/industrial  use upon completion of the
 remedy  by addressing low level  threat wastes  through
 consolidating them on-site in a RCRA Subtitle C hazardous  waste
 landfill.

      Crystalline Tetrachlorobenzene (TCB)  and Soils  Contaminated
      w-'th  TCB

      In  addition to  addressing  the  dioxin  contamination within
 on-site  soils and debris  at 5 ppb and above,  the remedy selected
 for OU2  will  address crystalline tetrachlorobenzene  (TCB) and
 soils having  TCB contamination  above  a  500 parts per million
 (ppm) action  level.  This  contamination exists in a small area of
 the central process  area of the site  where some time during
 active site operations  a TCB spill had occurred from a rail car
 parked at an  on-site siding.  Therafore, the remedy calls for the
 excavation of crystalline TCB material and TCB-contaminated soils
where the TCB concentration exceeds 500 ppm.  EPA's risk
 assessment has established that soils containing TCB
concentrations below 500 ppm do not pose an unacceptable risk to
 future site workers or  occasional bypassers.  Both the excavated
crystalline TCB material and the TCB  contaminated soils will be
taken off-site for treatment by incineration at a compliant RCRA-
regulated facility.

     Bagged Residential Soils from a  1990 Removal Action

       In 1990, Hercules, Inc.,  conducted a removal action
 involving the excavation of dioxin-contaminated soils from
contiguous residential  areas where the dioxin concentrations were
 1 ppb or greater.  The  1993 ROD for OU1 deferred the treatment
decision for  those soils, and the soils have  been stored on-site
 in bags until a  decision on the remedy  for similar on-site OU2
 soils would be made.  The total volume  of bagged soil  is
 estimated at  2,770 cubic yards, and the remedy selected in this
ROD calls for the on-site  consolidation within the RCRA Subtitle
 C landfill.

     Vertac Off-Site Areas ROD  Soils. Debris,  and  Sludges

     The remedy selected in the 1990 Off-Site Areas  ROD specified
 the removal of  sediments from the  active sewer interceptor and
 the installation of  pipe liners in the clean sewer,  the filling
 of the abandoned interceptor with  grout,  the removal of sludge

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 from the sludge digester in the old wastewater treatment plant,
 the capping of the sludge drying beds in the old wastewater
 treatment plant with one foot of clean soil, the draining of an
 aeration basin in the old wastewater treatment plant,  the
 demolition of the berm and capping of the basin with one foot of
 clean soil,  and the excavation of Rocky Branch Creek flood plain
 soils that are contaminated with dioxin at 1 part per billion
 (ppb)  and greater.   That ROD also selected on-site incineration
 of those excavated soils,  sediments and sludges,  and monitoring
 the Rocky Branch Creek and Bayou Meto fish for dioxin.

      Under the terms of a  Unilateral Administrative Order (UAO)
 issued to Hercules,  Inc. pursuant to CERCLA Section 106,  42
 U.S.C.  S 9606;  in July 1993,  Hercules,  Inc.,  has  completed the
 performance  of  the  1990 ROD's off-site  remedial actions  except
 for the excavation  of the  Rocky Branch  Creek flood plain soils
 and the on-site incineration  of sorUnents  removed from sewage
 collection lines,  sludge removed from the  digester,  and  the  as-
 yet unexcavated Rocky Branch  Creek soils.   The  removed sediments
 and sludge are  currently stored on-site.   Subsequent to  issuing
 the 1990  Off-Site Areas ROD,  EPA determined that  the off-site
 soils and debris  are  similar  in their physical  characteristics
 and in  the nature and extent  of contamination  in  that they all
 constitute low  level  threat media.   For that reason, EPA
 concluded that  it was  appropriate  to  defer  the  disposal  of the
 off-site  soils  and debris to  ensure  that such disposV vould be
 consistent with that  of the on-site  soils.

     Both  EPA's original Proposed  Plan for  the  Vertac Operable
Unit 2, presented to the public on May 25,  1995,  and the
 Supplemental Proposed  Plan for  OU2, presented to  the public  on
March 5,  1996,  stated  that EPA  intended to  address the disposal
of the  _,(90 Off-Site Areas ROD  wastes as a  component of the  OU2
remedy. In addition, both proposals  indicated that EPA's
preferred remedy  for those off-site  soils and debris was on-site
consolidation within the RCRA Subtitle C landfill due to their
similarity to OU2 contaminated  media.  Therefore, the public had
two opportunities to comment on this  change to  the remedy
selected  in the 1990 Off-Site Area*? ROD.  During  those two
comment periods,  EPA received no adverse comments to that  aspect
of the proposals.

     Therefore, in the absence  of  adverse comment,  EPA has
amended the 1990  Off-Site Areas ROD  and hereby  incorporates  the
change  in the disposal method for  off-site  soils  and debris
within the Vertac OU2  ROD.

     The  major  components  of  that amendment,  which are selected
 in  this ROD,  include  the consolidation  of  soils to be excavated
 from the  Rocky  Branch Creek  flood plain within the on-site RCRA
 Subtitle  C landfill.   Consistent with the  1990 Off-Site  Areas
 ROD, all  soils  with dioxin concentrations  greater than or equal
 to  1 ppb in  the Rocky Branch Creek flood plain will still be
 excavated.   In  addition, this ROD calls for the consolidation of

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 removed sediments from the sewage collection lines within the  on-
 site RCRA Subtitle C landfill.   Those sediments have been removed
 and are currently stored on-site.  Finally,  this ROD calls for
 the consolidation of removed digester sludges within the on-site
 RCRA Subtitle C landfill.   Those dioxin-contaminated sludges have
 been removed from the abandoned sewage treatment plant  sludge
 digester and are currently stored on-site.

      Underground On-Site Utility Lines.  Building Foundations and
      Curbed Areas

      The final component of the remedy selected in this  ROD
 relates to  on-site utility lines,  building foundations,  and
 curbed  areas.   Under this  remedy,  the underground utility lines
 will  be cleaned to remove  solids and  filled  with grout.   Solids
 from  the lines will be  consolidated within the  on-site RCRA
 Subtitle C  landfill.  Cutoff  barri'-s wi"] '-  installed  .round
 various underground utility lines to  prevent shallow water
 migration and  contaminant  transport, along the lines.

      The  remedy  selected for  the building foundations and curbed
 areas consists of  the cleaning  through hydroblasting and
 scarification, after which  they will  be  left  in  place.  Areas
with persistent  staining will be  sealed  rfith  epoxy type sealants.
Upon completion  of  the cleaning and scarification, the
 foundations and  curbed areas will be  covered with soil adequate
to support a vegetative cover and contoured to prevent erosion
and ponding.

     While the OU2  feasibility  study  (FS) identified five
underground storage tanks  (USTs) suspected of containing
petroleum products, and both the original May 1995 Proposed Plan
for OU2 ana the March 1996  Supplemental Proposed Plan for OU2
discussed those  five USTs, Hercules,  Inc., has recently taken
action to address those tanks by draining their  contents and
backfilling the tanks with  "flowabj.<-   grout containing a mixture
of cement, fly ash, and sand.   Therefore, this ROD need not
address the tanks.

STATUTORY DETERMINATIONS

     The selected remedy is protective of human  health and the
environment, complies with  Federal and State  requirements that
are legally applicable or relevant and appropriate  to the
remedial action, and is cost  effective.  Because this remedy
 involves on-site consolidation  of  low level  threat media,  it need
not satisfy treatment as a  principal  element of the remedy.
 Instead,  the remedy selected  is consistent with the NCP's
preference  for containment remedies when addressing low level
threat  media.   However,  because this  remedy  will result in the
 consolidation  within a  RCRA Subtitle  C hazardous waste  landfill
 of contaminated soils,  debris,  and sludges,  hazardous substances
 will  remain on a portion of the site  above  levels that  allow for
 unlimited use  and unrestricted  exposure. This is due to the fact

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that  the hazardous waste  landfill will  remain  in  place  for an
indefinite period of time,  and due to the  fact that  the above-
described 1984 Court-ordered remedy resulted in dioxin  wastes
remaining in place.  Therefore, EPA shall  review  the remedial
action no less than every five years after initiation of the
selected remedial action  to ensure that the remedy continues to
provide adequate protection of human health and the  environment.
That  five-year review is  required by CERCLA Section  121(c), 42
U.S.C. S 9621(c).
                                                    SEP  1 71996
J>ne It. Sagina
Regional Adm
 .    'v.PA Reg
or
                              Date

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                        TABLE OF CONTENTS

 1.0   SITE LOCATION AND DESCRIPTION  	    1

 2.0   SITE HISTORY AND ENFORCEMENT ACTIVITIES  	    4
      2.1  Site Operations History   . . ,	    4
      2.2  Enforcement Activities   	    6

 3.0   HIGHLIGHTS OF COMMUNITY PARTICIPATION   	   10

 4.0   SCOPE AND ROLE OF OPERABLE UNIT	   13

 5.0   SUMMARY OF SITE CHARACTERISTICS   	   20
      5.1  Demography and Land Use in the Area of the Site ...   20
      5.2  Soils and Geology  	   22
          5.2.1     Soils  	   22
          5.2.2     Geology  	   22
      5.3  Hydrology  	   25
          5.3.1     Surface Water 	   25
          5.3.2     Ground Water 	   25
     5.4  Remedial Investigation Findings  	   26
          5.4.1     Background  	   26
          5.4.2     Sampling Results for Surface Soils 	   30
          5.4.3     Subsurface Soils 	   36
          5.4.4     Tetrachlorobenzene Spill Area 	   36
          5.4.5     Underground Utilities  	   36
          5.4.6     Underground Storage Tanks  	   37
          5.4.7     Offsite Rocky Branch Creek and Bayou
                         Meto Flood Plain Soils  	   38
          5.4.8     Residential Bagged Soils  	   38
          5.4.9     Sludges and Sediments from Old Sewage
                         Treatment Plant Digester  	   38

6.0  SUMMARY OF SITE RISKS  	  39
     6.1  Risk Assessment Description  	  39
     6.2  Identification of Chemicals of Concern  	  40
     6.3  Human Health Risk Assessment   	  46
          6.3.1     Summary  	   46
          6.3.2     Exposure Assessment  	   46
          6.3.3     Toxicity Assessment  	   49
          6.3.4     Risk Characterization  	  67
          6.3.5     Uncertainty Analysis  	  72
          6.3.6     Central Tendency Exposure  	  76
     6.4  Ecological Risk Assessment  	  76
     6.5  Remedial Action Goals  	  79

7.0  DESCRIPTION OF ALTERNATIVES	  86
      7.1  Alternatives  	  86
      7.2  ARARs	104
          7.2.1     Federal ARARs   	  107
          7.2.2     State ARARs  	  124
          7.2.3     To-Be-Considered   	  131

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8.0  SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES	 132
     8.1  Comparative Analysis of Remedial Alternatives  	 134

9 . 0  THE SELECTED REMEDY  	 141
     9.1  Soils and Sediment Media  	144
     9.2  Underground Utilities and Tanks  	 146

10.  STATUTORY DETERMINATIONS  	 147
     10.1 Protection of Human Health and the  Environment   .... 147
     10.2 Compliance with ARARs  	 149
     10.3 Cost Effectiveness  	 150
     10.4 Utilization of Permanent Solutions and
               Alternative Treatment Technologies   	 151
     10.5 Preference for Treatment  	151

11.0 DOCUMENTATION OF SIGNIFICANT CHANGES  	 152

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                            LIST OF FIGURES

Figure 1  Site Location Map  	   2
Figure 2  Vertac Site Map  	   3
Figure 3  Land Use Zoning Map	  21
Figure 4  Geologic Map of Jacksonville Area 	  24
Figure 5  Remedial Actions Performed at the Site 	  27
Figure 6  Vertac Site Process Areas 	  28
Figure 7  Early Sampling Grids at Vertac 	  31
Figure 8  Sampling Grids in the Central Process Plant Area 	  32
Figure 9  Sampling Grids Outside Central Process Plant Area 	  33
Figure 10 Conceptual Model of Exposure Pathways 	  50
Figure 11 Conceptual Diagram of Soil Cover 	  92
Figure 12 Conceptual Model of Subtitle-C Landfill 	  93
Figure 13 Map Depicting Fenced (Restricted Access)  Area of
               the Site and Area where Access will be
               Unrestricted 	 143

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                      LIST OF TABLES
1
2
3
4
5
6
7
Table
Table
Table
Table
Table
Table
Table
Table 8
Table 9
Table 10
Table 11
Table 12
Table 13
Table 14
Table 15
Table 16
Table 17
Table 18
Table 19
Table 20
Table 21
Table 22
Table 23
Table 24
Table 25
Table 26
Table 27
Table 28
Table 29
Table 30
General Geologic Section for Site 	  23
Site Contaminants of Concern 	  34
Contaminants of Concern in Soil 	  41
Contaminants of Concern in Ground Water 	  42
Contaminants of Concern in Surface Water 	  44
                             Soil Ingestion 	  51
                             Dermal Absorption 	  52
                             Soil Inhalation 	  54
                             Vapor Inhalation 	  56
                             Surface Water Dermal	  57
                             Ground Water Ingestion ...  59
Model for Calculating Dose
Model for Calculating Dose
Model for Calculating Dose
Model for Calculating Dose
Model for Calculating Dose
Model for Calculating Dose
    Categorization of Carcinogenic Substances 	   61
    Cancer Slope Factors 	   62
    Chronic Reference Doses 	 	   63
    Subchronic Reference Doses 	   65
    Potential Lifetime Cancer Risk - Trespasser 	   69
    Potential Lifetime Cancer Risk - Current Worker 	   70
    Potential Lifetime Cancer Risk - Future Worker	   71
    Hazard Quotient/Index - Trespasser  	   73
    Hazard Quotient/Index - Current Worker 	   74
    Hazard Quotient/Index - Future Worker 	   75
    Central Tendency  - Cancer Risk/Hazard Indices 	   77
    Parameters Used in RME Risk Calculations 	   82
    Parameters Used in Monte Carlo Risk Calculations 	   83
    Comparison of RME and Monte Carlo Risk Calculations ...   85
    Remediation Goals for Contaminated  Soils 	   86
    Summary of Soils  Alternatives  	   88
    Quantities of Materials for Soils Alternatives 	   89
    Summary of Underground Utilities Alternatives 	  102
    Potential ARARs for the Vertac Site 	  106

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                       LIST OF ATTACHMENTS

Attachment A   -    [Foreword]  Original Responsiveness Summary

Attachment B   -    Supplemental Responsiveness Summary

Attachment C   -    Arkansas Department of Pollution Control
                      and Ecology Letter

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                        DECISION SUMMARY
                             FOR THE
                      VERTAC SUPERFUND SITE
                      JACKSONVILLE, ARKANSAS
                         OPERABLE UNIT #2
                          SEPTEMBER 1996
 1.0  SITE LOCATION AND DESCRIPTION

     The Vertac Incorporated Superfund Site (the site) is
 approximately 193 acres in size, and is located on Marshall Road
 in Jacksonville, Pulaski County, Arkansas, as shown in Figura 1.
 Jacksonville is about 15 miles northwest of the State Capital,
 Little Rock.  Approximately 1,000 residents live within one mile
 of the site with residential areas bordering the entire east and
 south sides.  The west and northern sides of the site are bounded
 by an industrial area and the Little Rock Air Force Base,
 respectively.

     The site consists of two parcels of land (Parcel 1 and
 Parcel 2)  that were acquired at different times during plant
 operations (Figur* 2).  Parcel 1 (the southern acreage),  which
 contains the central process area,  is approximately 93 acres and
has been in nearly continuous industrial use since 1948.   Parcel
 2, which is approximately 100 additional acres to the north, was
purchased by Vertac Chemical Corporation (Vertac) in 1978 but was
never used in the herbicides formulations operation.  In 1979,
the 2,4,5-T storage shed was built adjacent to the Regina paint
building,  which today is believed to contain empty Vertac 2,4,5-T
waste drums   Parcel 2 does not contain production facilities and
 is currently used by the United States Environmental Protection
Agency (EPA) for drum storage in newly-constructed warehouse
buildings.  An incinerator constructed under the contract to the
Arkansas Department of Pollution Control and Ecology (ADPC&E) to
burn drummed waste is also located in the northern part of
Parcel 1.

     Topographically, the land has moderate relief, sloping from
 about 310 feet above mean sea level (MSL) in the north to
 approximately 260 feet near the southwestern corner.  The central
 process area is located on a south plunging topographic nose
 bounded by Rocky Branch Creek on the west and Marshall Road on
 the east.  Land on the western side of Rocky Branch Creek has not
 been used for manufacturing or disposal and is topographically
 separated from the central process plant area by the creek.   Land
 on the eastern side  of Marshall Road has not been used for
 manufacturing and is geographically separated from  the central
 process plant area by Marshall Road.  Land on the northern  part
 of the site has not  been used for herbicide manufacture  and is
 generally up slope from the central process plant area.

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                                                   JACKSONVILLE

                                                   /
  SITE
LOCATION

Source: U.S. Geological Survey
     7.5 Minute Series
     Otmstead, AR (1967)
     Cabot, AR (1987)
     Jacksonville, AR (1987)
     McAlmont, AR (1986)
1248-331 11/16/92
  QUADRANGLE LOCATION
                              SITE LOCATION MAP, VERTAC SITE
                              JACKSONVILLE, ARKANSAS
                                     FIGURE 1

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                                r~*       vW^ ->^ Containerize
i                                Change   V*^Ł^ Soil Storage
                                House   __y      Warehouse
Storagd /TjT™"*^   HU  Laboratorv
Building//   eussand    '/I  Chemica,
:=:,.	XV  instrument Shop >VStorage_
===:=:=:=::=5Supervisorh
•Storeroom   ' offices
                                                                                                                       Legend
                                                                                                                       	Boundary Between
                                                                                                                                Parcels 1 and 2
                                                                                                                       •"•""•• Central Process Area
                                                                                                                       •"• e» ••§ Property Line
                                                                                                                              »• Rocky Branch Creak
                                                                                                                         Y///////A Buildings and Foundations
                                                                                                                          niiiirl Railroad
                                                                                                                         —»— Fence
                                                                                                                                                       600
                                                                                               Revised  February  1993
                                                                                                                                      SITE MAP, VEHTAC SITE
                                                                                                                                      JACKSONVILLE, ARKANSAS

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2.0   SITE HISTORY AND  ENFORCEMENT ACTIVITIES

2.1   SITE OPERATIONS HISTORY

      The first  facilities on the site were constructed by the
U.S.  Government in the 1930's and 1940's.  These facilities were
part  of a munitions complex that extended beyond the present site
boundaries.  Little is known about the operations that occurred
during that time period.  In 1948, the Reasor-Hill Company
purchased the property and converted the operations to
manufacture insecticides such as DDT, aldrin, dieldrin, and
uoxaphene.  During the 1950's, Reasor-Hill manufactured
herbicides such as 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-
trichlorophenoxyacetic acid (2,4,5,-T), and 2,4,5-
trichlorophenoxypropionic acid (2,4,5,-TP), which is also called
Silvex.  Drums  of organic material were stacked in an open field
immediately southwest  of the production area, and untreated
process water was discharged from the western end of the plant to
Rocky Branch Creek.

     Hercules Powder Company,  now known as Hercules, Inc.
(Hercules),  purchased  the Reasor-Hill property and plant in 1961
and continued to manufacture and formulate herbicides.   The drums
that were in the open  area southwest of the central process area
were buried in what is now referred to as the Reasor-Hill
Landfill.   From 1964 to 1968,  Hercules produced the herbicide
Agent Orange,  a mixture of equal parts of 2,4,5-
trichlorophenoxyacetic acid (2,4,5-T) and 2,4-
dichlorophenoxyacetic  acid (2,4-D).   Hercules discontinued
operations at the site in 1971.

     From 1971 to 1976, Hercules leased the plant site to
Transv?-*! ,  Inc.  (Transvaal), a predecessor company of Vertac.
Transvaal resumed production of 2,4-D and intermittently produced
2,4,5-T.  Organic wastes from these manufacturing processes were
stored and then buried by Hercules on the site in what is now
referred to as  the North Landfill area.  Transvaal purchased the
property and plant from Hercules in 1976.  In 1978, Transvaal
underwent a Chapter XI bankruptcy reorganization and ownership of
the site was transferred to the new company, Vertac Chemical
Corporation, which is  the present owner.

      In 1979, ADPC&E issued an order that required Vertac to
improve its hazardous  waste practices, and in 1980 EPA and ADPC&E
jointly filed suit in  federal district court against Vertac  and
Hercules.  A Consent Decree entered  into by EPA, ADPC&E, Vertac,
and Hercules in January 1982 required that an independent
consultant assess the  conditions of  pnsite wastes  and  develop  a
proposed disposal method for the wastes.  The proposal,  called
the "Vertac Remedy", was deemed by EPA to be unsatisfactory.   The
court decided  in favor of the  proposed remedy,  which was
implemented in  the summer of  1984 and  completed in July 1986.   As

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 part  of  the remedy,  the Vertac  plant  cooling water pond was
 closed,  and sediment from this  unit was removed and placed in an
 above-ground vault.   The Reasor-Hill  and Hercules/Transvaal
 Landfills were  capped,  and a  French drain and  leachate collection
 system were installed around  the burial (landfill) areas.  Ground
 water monitoring wells  were also installed, and a ground water
 monitoring  program was  initiated.

      Vertac operated the plant  until  1986.  On January 31, 1987,
 Vertac abandoned the site and declared bankruptcy, leaving
 approximately 29,000 drums of 2,4-D and 2,4,5-T wastes.  Many of
 these drums were corroded and leakj.nt,.  At tl*at time EPA
 initiated an emergency  removal  action to stabilize and secure the
 site.

      In  1988, ADPC&E contracted for the incineration of the
 drummed waste, using a  $10.7  million combined trust fund and
 letter of credit obtained from  Vertac during bankruptcy
 litigation.  A contract  for the incineration of the drummed waste
 was signed  in 1989 between ADPC&E and Vertac Site Contractors
 (VSC).  VSC  is a joint venture  of MRK Incineration and Morrison-
 Knudsen Environmental Services.  In January 1992,  ADPC&E approved
 the VSC trial burn and production incineration began.   Because of
 the difficulty in handling the Vertac drummed waste material,
 incineration operations took  longer than originally anticipated.
 In May 1993, the trust fund money had been expended with
 approximately 50 percent  of the waste destroyed under the State's
 contract.  In June 1993,  EPA took over the incineration operation
 and completed the incineration  of the D-waste drums in September
 1994.   EPA contracted for the off-site incineration of the
 remaining 3,100 drums of  T-waste.  Shipments of T-waste to the
APTUS commercial hazardous waste incineration facility, located
 in Coffeyv:"le, Kansas, concluded on March 29, 1996.

     On July 16, 1996, the Regional Administrator for EPA Region
 6 executed a Non-Time Critical  Removal Action Memorandum that
 concluded the on-site incinerator support activities associated
 with  the on-site D-waste  incineration, which had concluded on
 January 2,  1994.  That Action Memorandum authorized the off-site
 disposal of  33,000 drums  of salts (and the associated pallets)
 that  were generated  during the  on-site incineration of D-wastes,
 and it authorized the on-site disposal within the RCRA Subtitle C
 hazardous waste landfill  of both 10,000 shredded pallets used to
 store drummed waste  materials and of  6,300 drums of incinerator
 ash (and their associated pallets).   In that Action Memorandum,
 the Regional Administrator also granted a variance from the  RCRA
 Land  Disposal Restriction (LDR) treatment standard applicable to
 dioxin-containing wastes found  at 40  CFR S 268.31.  Specifically,
 the Regional Administrator approved a treatability variance  for
 the disposal of dioxin-contaminated wastes within the on-site
 RCRA  Subtitle C landfill of 5 ppb from the LDR standard  of 1 ppb

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pursuant  to  the  procedures  set  out  at  40  CFR  S  268.44.
Therefore, should the  LDR dioxin  treatment  standard be
applicable to  the on-site disposal  within the on-site RCRA
Subtitle  C hazardous waste  landfill if placement within the unit
occurs, the  treatment  standard  is 5 ppb.  See July 18, 1996, Non-
Time Critical  Action Memorandum in  Administrative Record for more
details.

     Currently,  there  are no manufacturing  operations at the
site.  At the  time operations were  shut down, Vertac "mothballed"
the plant.   Mothballing  involved  flushing process lines and
draining  several of the  process vessels.  Continuing activities
at the site  include operation of  an on-site wastewater treatment
plant by  Hercules, Inc.   The treatment plant  processes ground
water collected  in French drains  constructed  downgradient (south
and west) of the old waste burial areas,  and  surface water runoff
collected in a series  of  drainage ditches and sumps that surround
the central  process area.  This treated water was originally
piped to  the West  Wastewater Treatment Plant  owned and operated
by the city  of Jacksonville and was  discharged into Bayou Meto.
As part of ongoing remedial activities at the site, Hercules has
recently  completed the cleaning and  regrouting of certain
sections  of  the  sewer  lines that run through  the site to the West
Wastewater Treatment Plant,  and as  such,  water that was
discharged to the  sewer  interceptor  on the site is now treated
and discharged directly  into Rocky Branch Creek (after meeting
discharge limits established by ADPC&E).

     The Vertac  site was  added to the National Priorities List
(NPL)  of hazardous waste  sites in 1982.   Once the site was placed
on the NPL,  money  available from the Comprehensive Environmental
Response, Compensation, and Liability Act of  1980, commonly
called Superfund,  42 U.S.C.  § 9601  et seq..  could be used to
investigate  and  study the problems  at the Vertac site and find
ways to correct  them to protect the  public health and the
environment.

2.2  ENFORCEMENT ACTIVITIES

     A Potentially Responsible Party (PRP)  search was not
conducted since  the Agency knew the identities of former owners,
operators, and some generators of waste at  the Vertac site, and
since litigation was already ongoing prior  to CERCLA activities.
However,  CERCLA  Section  104(e)  information  request letters were
mailed in March  1990,  and later to  several  companies which had
"tolling  agreements'* with the Vertac Chemical Corporation and/or
Hercules.

     The  following is  a  chronology  of  enforcement activity  at  the
Vertac site:

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1.   Litigation was filed  in 1980 under Section 7003 of the
     Resource Conservation and Recovery Act  (RCRA), 42 U.S.C. §
     6973, and other statutes by the United  States and the State
     of Arkansas against Vertac Chemical Corporation and Hercules
     Inc.  (the Parties).   In January 1982 EPA and the State of
     Arkansas entered into a Consent Decree  with Vertac Chemical
     Corp. and Hercules, Inc., in the litigation for developing a
     remedial plan for  certain on-site and off-site areas.  After
     EPA invoked dispute resolution and had  a hearing on the
     remedy, the Court  ordered the implementation of the "Vertac
     Remedy" in July 1984  (see Site History  for a discussion of
     the action taken).

2.   In July 1986, pursuant to an agreement  between the parties
     and entry by the court, Vertac established an Environmental
     Trust Fund as part of a bankruptcy agreement.  Vertac placed
     $6,700,000 in this fund to be used to remediate portions of
     the plant.   A $4,000,000 letter of credit was later added to
     this Trust Fund also for the purpose of future site
     remediation.   Both EPA and the State of Arkansas had access
     to this fund which was later used to incinerate the 29,000
     drums of waste left at the site by Vertac.

3.   In August 1986 EPA issued a Unilateral Administrative Order
     (UAO)  pursuant to Sections 104 and 106 of CERCLA,  42 U.S.C.
     SS 9604 and 9606,  to all PRP's to require posting of warning
     signs and the fencing of portions of the West Wastevattr
     Treatment Plant and certain areas of Rocky Branch Creek.
     This work was performed by Hercules.

4.   In January 1987 EPA issued a notice letter to Vertac
     Chemical Corp. that required Vertac Chemical Corp. to
     continue operation and maintenance of the leachate
     collection and treatment system which was established around
     old on-site waste burial areas.

5.   In June 1938 EPA signed an Administrative Order on Consent
     (AOC)  pursuant to  Section 106 of CERCLA, 42 U.S.C. S 9606,
     with Hercules to allow Hercules to implement the fine grid
     sampling investigation for specific off-site areas.

6.   In September 1988  EPA signed an AOC pursuant to Section 106
     of CERCLA, 42 U.S.C.  S 9606, with Hercules that required
     Hercules to remove approximately 3,000  cubic yards of
     dioxin-contaminated soil from residential yards near the
     facility.

7.   In July 1989 EPA signed an AOC pursuant to Section  106  of
     CERCLA, 42 U.S.C.  S 9606, with Hercules that required
     Hercules to conduct the on-site Remedial
     Investigation/Feasibility Study  (RI/FS).

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8.   In March  1990 EPA sent CERCLA Section 104(e) information
     request letters to several companies which had been involved
     in business deals with the Vertac Chemical Corp. and
     Hercules  Inc., including  "tolling agreements".

9.   In July 1990 EPA sent General Notice letters to the PRP's
     regarding the proposed off-site remedial plan and other site
     actions.

10.  In February 1991 the U.S. District Court for the Eastern
     District  of Arkansas entered a Consent Decree between the
     United States and "Phoenix Parties", which are companies
     related to the Vertac Chemical Corp., and which carried on
     the remaining business of Vertac under their names after
     Vertac abandoned the site.  Hercules appealed the entry of
     the Consent Decree to the Eighth Circuit Court of Appeals,
     which upheld the entry of the Consent Decree in April 1992.
     Under the terms of the Consent Decree,  the Phoenix Parties
     have contributed $1,840,000 to a RCRA Closure Trust Fund,
     and will contribute a percentage of pre-tax profits for 12
     years, in return for release of liability.

11.  Hercules,  Inc.,  had opposed the United States'  efforts to
     select various CERCLA remedies at Vertac.   This opposition
     included a motion filed in September 1992  to enforce the
     1982 RCRA Consent Decree.   The parties were ultimately
     unable to resolve their differences regarding this motion.
     In June 1992 the District Court entered an order denying
     Hercules'  motion to enforce the Consent Decree and allowed
     EPA to utilize CERCLA procedures to select remedies for the
     Vertac site.

12.  The United States added CERCLA Section 107,  42 U.S.C.  §
     S»ou7,  cost recovery claims against Hercules,  Dow Chemical
     Company,  and Uniroyal Chemical Limited of Canada, in a
     complaint filed in March,  1992.  By order of the trial court
     in June 1992,  this complaint was administratively closed,
     and the claims asserted against Hercules,  Dow, and Uniroyal
     were consolidated with the existing litigation.  Other
     parties,   including BASF AG, Standard Chlorine, and Velsicol,
     have been added to the litigation as third-party defendants.

13.  Special notice letters for Remedial Design/Remedial Action
     (RD/RA) for the off-site  areas were sent to the PRP's in
     August 1992.  No "good faith" offers were received in
     response  to the letter.   A subsequent special notice letter
     was sent  in December 1992 to the PRP's after EPA revised  the
     scope of  the remedial work at the off-site areas.
     Negotiations regarding this work did not result  in an RD/RA
     Consent Decree.

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 14.   In June  1993  EPA issued a  Unilateral  Administrative  Order
      (UAO) pursuant  to Section  106  of  CERCLA,  42  U.S.C. S 9606,
      to Hercules requiring  it to  implement the Remedial Design
      and Remedial  Action  for the  Off-site  ROD, which was  signed
      in September  of 1990.

 15.   In March 1994 EPA issued another  UAO  pursuant to Section 106
      of CERCLA, 42 U.S.C. S  9606, to Hercules  requiring it to
      implement the Remedial  Design  and Remedial Action for the
      Operable Unit 1 ROD, which was signed in  June of 1993.

 16.   The liability phase of  the on-going -itigation was completed
      in October 1994, when the United  States was granted  a motion
      for summary judgement against  Hercules, Inc., holding it
      jointly  and severally liable to the United States for past
      and future response costs incurred at the site.  The claims
     made by the United States were against Hercules,  Inc., Dow
     Chemical Company, and Uniroyal ^nder CERCLA Section  107, 42
     U.S.C. S 9607, for recovery of costs related to the Vertac
     site,  including EPA removal costs.  The claims against Dow
     and Uniroyal were based on tolling agreements that those
     companies had with Vertac,  where they sent raw materials to
     Vertac for processing into finished product that was shipped
     back to them.   These tolling agreements constituted
     arrangements for disposal pursuant to CERCLA Section
     107(a)(3), 42  U.S.C.  S 9607(a)(3).  Prior to a liability
     phase trial,  the United States settled its claims against
     Dow through a  Consent Decree for $3.5 million.   Settlements
     were also reached with Velsicol and the United States on
     behalf of the  Department of Defense.

     The only United States claims remaining unresolved after
     these ~,ettlements were those against Uniroyal.   The
     liability phase of the trial against Uniroyal was concluded
     in November 1993.  A jury,  sitting both as an advisory jury
     and a fact-finding jury, returned a verdict finding Uniroyal
     also liable at the site for CERCLA Section 107 costs, but
     that its involvement was divisible.  To date, the Court has
     not entered its order addressing the findings of the jury,
     and the cost phase of the trial has not been initiated.

17.  Although not specifically enforcement related, several
     separate citizens suits were filed seeking to halt
      incineration of the 29,000 drums  of dio:cin contaminated
     still bottom wastes which were stored at  the site.   They are
     as follows:

     After the incineration  contract was finalized, but before
     the first trial burn, came National Toxics Campaign  (NTC).
      et.al. v. Arkansas Department  of  Pollution Control and
      Ecology  (ADPC&E). et. al.. seeking to enjoin the impending
      trial burn.  After six  days  of testimony, the trial  court

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     denied a preliminary injunction based on the merits.  NTC
     subsequently dismissed its lawsuit in federal court.

     Incineration opponents sued again, in State chancery court,
     on the morning of the same trial burn approved in federal
     court during the NTC litigation.  This suit, Rubv Brown and
     Sharon Golqan v. ADPC&E. was filed in Pulaski County
     Chancery Court.  The chancellor denied the temporary
     restraining order on the merits after a hearing that day.

     After thousands of D-waste drums had been burned, ADPC&E's
     director announced that T-waj^e would b_ burned after a
     limited burn of T-waste so that ambient air and incinerator
     stack data could be evaluated for risk considerations.   This
     announcement brought the lawsuit by the Arkansas Peace
     Center (APC) gt aj^, in October 1992.  During this
     litigation, control of the incineration passed from State to
     EPA control, after State funds were exhausted.

     The APC litigation resulted in a preliminary injunction (the
     March 17,  1993, order mentioned above),  a subsequent stay of
     that injunction by the Eighth Circuit based on both
     jurisdiction and the merits,  and eventual dismissal due to
     lack of jurisdiction.

     After denial of a petition for certiorari to the U.S.
     Supreme Court,  plaintiffs filed suit again in chancery court
     in April 1994.   That case was removed to federal court and
     eventually dismissed.  In the dismissal order, the district
     court found that the lawsuit was barred by CERCLA 113(h), 42
     U.S.C. S 9613(h), since the lawsuit was clearly designed to
     stop incineration.  The District Court also found that
     dismissal was appropriate based on res judicata. i.e..  that
     the same case had already been tried.

3.0  HIGHLIGHTS OF COMMUNITY PARTICIPATION

     A community relations plan for the Vertac site was put in
place in 1983.  This plan listed contacts and interested parties
within the federal, state, and local governments, various
organized affiliations, and local citizens.  It also established
communication pathways to ensure timely dissemination of
pertinent information about site activities.  Extensive community
outreach has been performed in Jacksonville over the years
through the release of information fact sheets, by conducting
frequent open houses and work shops, and  through numerous
meetings with local civic groups and media representatives
(newspapers, radio  and TV).  Reports updating activities at the
site are also distributed to the Mayor,  interested civic groups,
and the local media on a weekly basis.    A satellite community
relations office was  established  in  Jacksonville in  July 1990 to
                                10

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provide  easy  access  to  documents  and  information, and to provide
a  local  contact  for  questions  and concerns.

     A Technical Assistance Grant (TAG) was awarded by EPA in
1989 to  a citizens group  called Jacksonville People With Pride
Clean Up Coalition  (JPWPCUC).  This award was challenged by
citizen  groups that  had competed  for  the grant and who alleged
that JPWPCUC  was funded by the Potentially Responsible Parties
(PRP's)  for Vertac.  Upon investigation by EPA, the grant was
annulled after it was determined  that the JPWPCUC TAG application
listed their  source  of  matching funds as a bank account shared
with their larger "parent" group,  che Jacksonville People With
Pride.   This  parent  group had  indeed  accepted monetary
contributions from Vertac PRP's,  and  since these funds were not
distinct from those  of  JPWPCUC, EPA determined that a possible
conflict of interest could exist,  resulting in annulment of the
TAG in December  1991.

     TAG availability was again advertised in January 1992,  and
the grant was awarded to  the Concerned Citizens Coalition (CCC)
in April 1993 after  considerable  effort by EPA to facilitate
consolidation of four competing citizen groups.  CCC then
solicited several technical groups in order to select a technical
advisor  for the TAG.  The Environmental Compliance Organization
(ECO)  was selected as the technical advisor and actively reviewed
site documents for the community.

     In February 1995 EPA released the draft feasibility study
(FS) for Operable Unit 2,  and several meetings were held in
Jacksonville with local citizens groups and the press to discuss
the various options  being considered.   The Operable Unit 2 FS was
finalized in April 1995,  and was made available to the public at
five local repositories (Jacksonville City Hall, Public Library,
Police Courts Building, Air Force Base Library, and ADPC&E).  The
official Administrative Record for this Operable Unit is
maintrined at EPA in Dallas, the  Jacksonville City Hall, and the
Arkansas Department  of  Pollution  Control and Ecology in Little
Rock.

     In  the feasibility study, EPA assumed that the future land
use for  the site, based on past land  use and existing zoning
ordinances, would be commercial/industrial.  This reasonably
anticipated future use  for this site  is consistent with EPA's
directive "Land  Use  in  the CERCLA Remedy Selection Process,"
OSWER Directive  No.  9355.7-04, May 25, 1995.

     On  May 25,  1995, EPA held an informal open house  in
Jacksonville  to  discuss EPA's  proposed plan of action  for
contaminated  soils at the Vertac  site.  The meeting was well
attended by Jacksonville  citizens, members of  the city
government, State Health  Department representatives, numerous
local civic groups,  and the technical advisor  for the  TAG grant.

                                11

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At that  time,  the  proposed plan was released to the public  for
review and  comment.   Several weeks prior to the informal open
house, the  EPA project manager met with the local press to
discuss  the major  elements of EPA's proposed plan which received
coverage in both local papers and the State paper.  At this open
house, EPA  discussed  with the community the anticipated future
land use scenario  for the site, which formed the basis for  EPA's
risk assumption.   That risk assumption presupposed that the
future usage of the site would remain consistent with both  past
land use and current  zoning for the site area, which is
commercial/industrial.  Therefore, the EPA derived the site's
cleanup  level  of 5 parts per billion (ppb) toxicity equivalents
(TEQ) for dioxin due  to the fact that a commercial/industrial
human exposure scenario assumes that a worker would be exposed to
post-cleanup dioxin levels over a 40-hour-per-week period.  This
worker exposure scenario additionally is protective of a
trespasser or  a passerby, both of whose exposure period would be
less than that ox a site worker.

     On June 15, 1995, EPA held a formal public meeting in
Jacksonville at the community civic center to discuss EPA's
proposed cleanup scenario for dioxin-contaminated soils at the
Vertac site.  At that meeting EPA attempted to address all
comments or questions raised concerning the proposed cleanup and
formally accepted all public comments.   Over 100 citizens
attended the meeting,  including members from the Jacksonville
Chamber of Commerce, Jacksonville City Council, the Mayor,
representatives from ADPC&E,  and the State Health Department.
The comment period for the proposal ran from May 26 through
August 11, 1995, after EPA granted two extensions of time.  All
comments received by EPA prior to the end of the public comment
period,  including those expressed verbally at the public meeting,
are addressed  in the Responsiveness Summary section of this
Recorv- >,f Decision.  Thus, the requirements of CERCLA Sections
113(k) (2) (B) (i-v) and 117, 42 U.S.C. SS 9613(k) (2) (B) (i-v) and
9617, were met during the remedy selection process.  During both
the May open house and the June public meeting, the community
indicated its  approval and acceptance of EPA's reasonably
anticipated land use  for the site and the risk assumptions  based
on that  anticipated future land use.

     EPA's original proposal for remediation of soils,
foundations and underground utilities at Vertac was presented to
the community  at an informal open house held in Jacksonville on
May 25,  1995.  At  that time EPA's preferred alternative called
for the  off-site incineration of dioxin-contaminated hot  spots
and on-site landfilling of dioxin contaminated soils that
exceeded a  site-specific commercial/industrial exposure level.
Under this  scenario approximately two-thirds of the site  would
have potentially been available for future  commercial  reuse.
                                12

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      Following the  release  of  the  original Proposed Plan  for OU2
 in May  1995  and the subsequent community meetings, EPA
 Administrator  Carol M.  Browner issued  a series of administrative
 reforms for  the Superfund Program  on October  3,  1995.  One
 purpose of the reforms  was  to  control  remedy  costs and to promote
 cost  effectiveness,  and the reforms directed  EPA to base site
 cleanup decisions on practical future  land usage and reasonable
 contaminant  exposure scenarios.

      As a result of those reform measures, and due to the ongoing
 deadlock over  the Federal budget, occurring at the time, Region 6
 revised the  proposed plan of action for OU2.  The Supplemental
 Proposed Plan  was issued on February 26, 1996, and presented to
 the public at  an Open House on March 5, 1996.  The Supplemental
 Proposed Plan  for OU2 eliminated the off-site incineration
 component of the original proposed plan, included capping in-
 place soils having  dioxin contamination between  5 to 50 ppb, and
 proposed on-site landfilling of soil contaminated with dioxin in
 excess  of 50 ppb.  The community objected strongly to the
 Supplemental Proposed Plan.

     After the March 5, 1996,  Open House,  EPA representatives
 conducted numerous meetings with several community groups to
 listen to the concerns of the  local residents.  Following the
March 5, 1996,  release of EPA's Supplemental Proposed Plan for
OU2,  EPA held another comment period to accept formal public
comment on the supplemental plan.   The response to these comments
 is contained separately from the original responsiveness summary
 in the "Supplemental Responsiveness Summary,1* which is included
as Attachment B to this document.   Subsequently,  EPA conducted
another open house on July 30,  1996,  to present to the public the
remedial elements it had reconsidered and currently held under
consideration at the time.   In general, EPA has responded to
community concerns and has reevaluated the OU2 FS and the two
proposed plans,  and the elements discussed during the July 30,
 1996,  Open House are now contained in this ROD.

 4.0  SCOPE MID ROLE OF OPERABLE PHIT

     The problems at the Vertac Superfund site are complex, and
 the EPA has determined that site remediation can be accomplished
 most efficiently in six phases.  This ROD addresses one of the
 six cleanup phases,  i.e.. Operable Unit 2, which consists of on-
 site soils,  off-site soils  and sediments, underground utility
 lines,  building  and equipment  foundations, curbs, and pads.

     The studies undertaken at the Vertac Superfund site  for
 Operable Unit  2  media have  identified  the soils  at the site to be
 a low-level  threat  in light of all the media  being remediated at
 the site.  EPA has  made that determination with  respect to  the
 site  soils and associated debris,  which includes contaminated
 media having similar dioxin contamination levels.  Those  media

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 include treatment residues  from the on-site  incineration of D-
 waste, dioxin-contaminated  drums, containers, pallets, personal
 protective clothing and equipment, process equipment and
 structures, and sludges and sediments associated with historical
 treatment of wastewaters.   EPA has defined these media as
 constituting low-level threats in contrast to principal threats.

     Generally, EPA associates principal threats with liquids,
 areas contaminated with high concentrations  of toxic compounds,
 and highly mobile materials that generally cannot be reliably
 contained.  See NCP Section 300.430(a)(iii)(A), 40 CFR S
 300.430(a)(iii)(A).  Low-level threat wa~_es are those source
 materials that can be reliably contained and that would pose only
 a low risk in the event of a release.  Wastes that generally are
 considered to constitute a  low-level threat  include surface soils
 containing contaminants of concern that are relatively immobile
 in air or ground water, i.e.. non-liquid, low volatility, and low
 leachability.  See "A Guide to Principal Threat and Low Level
 Threat Wastes," November 1991, OSWER Directive No. 9380.3-06FS.
 That guidance document states where toxicity and mobility of
 source material combine to pr^e a potential risk of 10~3 (1 in
 1,000 excess cancer deaths)  or greater,  treatment alternatives
generally should be evaluated.  In addition,  NCP Section
 300.430(a)(iii)(B),  40 CFR S 300.430(a)(iii)(B), in
characterizing EPA's remedial program expectations, states:

     EPA expects to use engineering controls, such as
     containment,  for waste that poses a relatively
     low long-term threat or where treatment is
     impracticable.

     Therefore, on-site consolidation within a RCRA Subtitle C
hazardous waste landfill is appropriate for these low level
threat dioxin-contaminated media because EPA's threat guidance
would only direct EPA to consider other treatment alternatives
where those media would constitute a principal threat.  Such a
determination would only arise when the overall dioxin
 concentration would exceed 5,000 ppb (three  orders of magnitude
 above the 5 ppb dioxin cleanup level identified in its site-
 specific risk assessment as protective for commercial/industrial
 exposures).

     The concentrations of  dioxin present in Vertac soils are
 generally an order of magnitude lower than the concentrations
 found in the dioxin-containing liquids  (both drummed still bottom
 wastes and process tank sludges), and as such, are identified  as
 a low-level threat based on relative concentration to other site
 media.  The dioxin in the Vertac soils also  fit the definition of
 a low-level threat due to the fact that they are  relatively
 immobile except through sediment transport,  i.e..  soil migration
 from rainwater runoff.  Dioxins are characterized as  having  a
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 very low solubility in water  and  a  very  low vapor pressure  (they
 do not readily leach to ground water  or  vaporize to the  air).   In
 addition,  numerous  studies  have also  shown that dioxin binds
 tightly to fine-grained and organic-rich soils, further  reducing
 its mobility.

      Dioxin, however,  is considered to be a highly toxic
 compound,  and  if  left unremediated  would continue to present a
 serious threat to the public  health and  the environment  due to
 the potential  for cancer and  noncancer effects, and would also
 continue to present potential long  term  threats to the
 environment from  the migration of contaminants off-site  through
 various sediment  transport  mechanisms.

      Remedial  action objectives have been developed to address
 the compounds  of  concern at this site, namely, 2,3,7,8-
 tetrachlorodibenzo-p-dioxin (TCDD or dioxin)  and other dioxin and
 furan congeners,  chlorobenzene, chlorophenoxyherbicides,
 chlorophenols, and  toluene.   The remedial action objectives are
 formulated  in  such  a way that residual contaminant concentrations
 in  the media of concern  are reduced or controlled to a level
where exposure of an environmental receptor to the contaminants
does  not result in  an unacceptable carcinogenic risk or an
 adverse toxic response when considering the reasonably
anticipated land use  intended for the site.   EPA's risk
assumption for OU2  presupposed that the future usage of the site
would remain consistent with past land use and the current zoning
 for the site area,  which  is commercial/industrial.   Therefore,
the EPA derived the site's cleanup level of 5 parts per billion
 (ppb) toxicity equivalents  (TEQ)  for dioxin due to the fact that
a commercial/industrial human exposure scenario assumes that a
worker would be exposed  to post-cleanup dioxin levels over a 40-
hour-per-week period.  This worker exposure scenario additionally
 is protective of a  trespasser or a passerby,  both of whose
 exposure period would be  less than that of a site worker.

      The remedial action objectives, developed to address the
 low-level threats present at  the site, which are applicable to
 the OU2 media  are as  follows:

 •     Prevent exposure of future site workers to concentrations  of
      site contaminants  in surface soils  that remain following
      remedial  activities which would result in an excess lifetime
      cancer risk  greater than 1 in  10,000 to 1 in a 1,000,000.

 •     Complete  the soils remedial  action  activities to result  in
      average dioxin concentrations  no greater than 1 ppb.

 •     Prevent exposure of future site  workers to concentrations  of
      site  contaminants that would result in an adverse  toxic
      response.


                                15

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 •     Prevent off-site environmental receptors from exposure to
      site  contaminants that would result  in an adverse toxic
      response.

 •     Prevent/control dust generation during remedial activities
      and/or removal activities to the maximum extent practicable.

 •     In concert with OU3  (ground water) remedial activities,
      prevent potential contamination of the on-site and off-site
      ground water by releases from below-ground portions of the
      plant, and

 •     Destroy and/or contain hazardous substances generated by the
      remediation.

      Following is a description of the six cleanup phases or
 operable units that are currently in progress, or have been
 completed at the Vertac site.   Collectively,  the completion of
 all six phases is intended to address all environmental risks
 posed by the site.

 Phase 1   The "VERTAC REMEDY"

     ADPC&E issued an order in 1979 that required Vertac,  Inc.,
 to improve its hazardous waste practices,  and in 1980 EPA and
ADPC&E jointly filed suit in federal district court against
Vertac, Inc.,  and Hercules,  Inc.   A Consent Decree entered into
 by EPA, ADPC&E, Vertac,  and Hercules in January 1982 required an
 independent consultant to assess the conditions of on-site wastes
 and to develop a proposed disposal method for the wastes.   The
proposal,  called the "Vertac Remedy",  was deemed by EPA to be
 unsatisfactory and EPA returned to court in early 1984 for a
 resolution.  The court decided in favor of the proposed remedy,
 which was implemented in the summer of 1984 and completed in July
 1986.

     As part of the remedy,  the Vertac plant cooling water pond
 and the equalization basin were closed and sediments from these
 units were removed and placed into an excavated area where
 earlier operators had buried drums of waste.   The burial area was
 capped and a French drain and leachate collection system were
 installed around the burial areas.  Ground water monitoring wells
 were  also installed and a ground water monitoring program was
 initiated.

 Phase 2   DRUMMED WASTE INCINERATION

      In 1989, ADPC&E signed a contract to have approximately
 29,000 barrels of 2,4-D and 2,4,5-T herbicide still bottom wastes
 incinerated on-site.  Wastes from the production  of 2,4,5-T at
 this  site have been found to contain up to 50 ppm of  dioxin,
 while wastes from the production of 2,4-D generally contain

                                16

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dioxin  in the  low parts per billion range.  All drummed wastes
are treated as F-listed (dioxin containing) wastes pursuant to
the Resource Conservation and Recovery Act  (RCRA), 42 U.S.C. §
6901 et seq.

     To accomplish this incineration, the State used funds from
the trust fund that was established when Vertac went bankrupt.
Incineration of these wastes began in fall 1990.  In June 1993,
funding for the project was depleted and EPA assumed immediate
responsibility for incinerating the remaining drums as a time-
critical removal action undertaken pursuant to CERCLA Section
104, 42 U.S.C. S 9604.  In late September 1994, the incineration
of 25,179 drums of dioxin-contaminated 2,4-D waste was completed
at the Vertac  site.  In July 1995 EPA announced that it would
pursue the off-site incineration of approximately 3,200 drums of
dioxin containing 2,4,5-T waste located at the Vertac site.  On
November 9, 1994, a contract was signed between the APTUS
commercial incineration facility in Coffeyville, Kansas, and
EPA's prime contractor URS Consultants,  to accept the Vertac
drummed T-waste material.   The first shipment of T-waste went to
APTUS in November 1994,  and the last shipment was sent off-site
on March 29,  1996.

Phase 3   VERTAC OFF-SITE AREAS

     A Record of Decision (ROD)  was signed in September 1990 to
address the cleanup of contiguous off-site areas that were
contaminated as a result of untreated and partially treated
surface and underground discharges of plant wastewater and other
releases.   Elements of this operable unit include an active sewer
interceptor and an abandoned sewer interceptor, portions of an
old abandoned trickling filter wastewater treatment plant, an
active Wes+ Wastewater Treatment Plant,  ind the Rocky Branch
Creek flood plain.   The selected remedy called for removing
sediments from the active sewer interceptor, installing pipe
linern in the clean sewer, filling the abandoned interceptor with
grout, and removing sludge from the sludge digester in the old
wastewater treatment plant.  Sludge drying beds in the old
wastewater treatment plant were capped with one foot of clean
soil and the aeration basin in the old wastewater treatment plant
was drained and demolished.  Flood plain soils along Rocky Branch
Creek that are Contaminated with dioxin in excess of one part per
billion (ppb)  will be excavated for treatment at Vertac.
Monitoring of  fish in Rocky Branch Creek and Bayou Meto for
dioxin will continue.

     As EPA proceeded with overall site remediation, it concluded
that it was appropriate to defer the disposal  of the contaminated
soil and debris addressed in the  1990 Off-Site Areas ROD  to make
the disposal of excavated off-site soils  and debris consistent
with the disposal of on-site soils and debris.  All other
elements of the off-site  remedial  action,  except  for the  above-

                                17

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mentioned  off-site  soils and debris disposal and the excavation
of  flood plain  soils were completed in November 1995.

     Hercules has completed the remedial design and has started
the remedial action under the terms of a Unilateral
Administrative  Order issued in July 1993.  The Order requires
Hercules to conduct the remedial design and remedial action to
implement  the selected remedy, except the on-site incineration of
soils excavated from the Rocky Branch Creek flood plain and
contaminated sludges and debris from sewage treatment plant and
sediments  from  the  interceptor lines was deferred to make the
disposal of excavated off-site soils consistent with the disposal
of  on-site soils.   All off-site remedial actions (except for the
excavation of flood plain soils) were completed in November 1995.
The excavation  of the flood plain soils is expected to be
completed  in early  1997.

Phase 4    ON-SITE ABOVE GROUND MEDIA (Operable Unit #1)

     A ROD for  the  above ground media was signed in June 1993.
The above  ground media includ« buildings, process equipment,
leftover chemicals  in the process vessels,  spent activated
carbon,  shredded trash and pallets, and miscellaneous drummed
wastes at the site.  The selected remedy consisted of:  (1)  On-
site incineration of F-listed process vessel contents,  spent
carbon,  shredded trash and pallets, and miscellaneous drummed
wastes;  (2) off-site incineration of PCB transformer oils and
non- F-listed process vessel contents; (3)  recycle/reuse of
decontaminated process equipment to the maximum extent
practicable; (4) on-site consolidation of debris resulting from
demolition of buildings and equipment that cannot be
recycled/reused in  a RCRA subtitle C landfill; (5)  the deferral
of a decision on the treatment of approximately 2,770 cubic yards
of TCDD-contaminated residential soils Hercules, Inc.,  had
excavated  as a  removal action in 1990 from contiguous residential
areas south of  the  site; (6) disposal of treatment residues
consistent with disposal of ash and salt that was generated by
the incineration of drummed wastes at the site; and, (7) the
construction of a RCRA Subtitle C landfill on-site.

     A Unilateral Administrative Order (UAO) was issued to
Hercules,  Inc., in  March 1994 requiring  it to perform the
remedial design and remedial action under the ROD for OU1.
Hercules'  remedial  design work plan has been approved.  Part  of
the work plan expressed interest in pursuing off-site
incineration as the means to perform the actions under the  ROD.
Therefore, Hercules has signed  a contract with  APTUS,  an off-site
commercial hazardous waste  incineration  facility.   An  Explanation
of  Significant  Difference  (BSD) was  issued  in May  1995  by  EPA to
allow such off-site incineration.  Hercules has completed  off-
site incineration of F-listed and  non- F-listed liquids and
solids that were present in the process  vessels.   The  remedial

                                18

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 design  is  expected to  be  complete  by  the  end  of  1996.  Hercules
 has  commenced construction  of  the  on-site RCRA Subtitle C
 landfill,  with completion expected in November 1996.  Also,
 Hercules has  commenced the  off-site shipment  of  activated carbon
 that was used for  the  treatment of leachate and  storm water,
 which should  be completed by the end  of 1996.  All remedial
 actions for this Operable Unit are expected to be completed by
 the  end of 1997.

 Phase 5   SOILS AND UNDERGROUND UTILITIES (Operable Unit 2)

     Operable Unit  2 (OU2) media are  the subject of this ROD,
 which addresses surface and subsurface soils, underground
 utilities, foundations, curbs  and pads. In addition, in
 conjunction with an amendment  to the  1990 Off-Site Areas ROD, the
 ROD  for OU2 addresses media originally intended to be addressed
 by the  1990 Off-Site Areas ROD, which consist of cont-iguous soils
 from the Rocky  Branch Creek flood plain, sludge from the Old
 Sewage  Treatment Plant sludge digester, and the sediment from the
 associated interceptor lines (which are considered to be
 contiguous to the sita due to the continuous connection to the
 site via the  sewer  interceptor).   Finally, the ROD for OU2 also
 addresses bagged soils Hercules had excavated from contiguous
 residential yards in 1990 as part of a removal action,  the
 treatment of which  EPA deferred in the OU1 ROD.

     Because of the similarity of OU2 media to the media from the
 1990 Off-Site Areas ROD and contiguous off-site residential soils
Hercules had excavated during a 1990 removal action, EPA has
 chosen to address them in the OU2 ROD so that similar waste
materials associated with the Vertac site would be treated in a
 consistent manner.

     The 1990 Off-site Areas ROD called for the excavation and
 incineration  of soils in the flood plain area along Rocky Branch
 Creek that had a 2,3,7,8-TCDD concentration greater than 1 ppb.
 The estimated volume of flood plain soils is approximately 4,100
 cubic yards.  The 1990 Off-site Areas ROD also called for the
 incineration  of sludges removed from  the digester and sediments
 from the interceptor that connected the Old Sewage Treatment
 Plant to the  Vertac facility.  The  approximate volume of sludges
 from the digester  is 800  cubic yards, and the approximate volume
 of sediments  from the  interceptor  line is 2 cubic yards.  The ROD
 for OU1 deferred the treatment decision for the  bagged soils
 removed from  residential  yards as  a part  of a removal action in
 1990.   The total volume of  bagged  soil is estimated at 2,770
 cubic yards.   The  final disposition of these  materials will be
 discussed  in  detail in Sections 7  and 9.
                                19

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Phase  6   GROUND WATER  (Operable Unit #3)

     Hercules  completed the Remedial Investigation/Feasibility
Study  (RI/FS)  for  this phase of the site cleanup in September
1995.  Remedy  selection is expected to occur in September 1996.

     Ground water  remediation at the Vertac site will pose
certain technical  challenges due to the combination of complex
subsurface geology (tilted, fractured bedrock), and the presence
of dense nonaqueous phase liquids  (DNAPL's).  Ground water is
generally contaminated with chlorophenols,
 ^hlorophenoxyherbicides, and dioxin.  More detailed information
on groundwater will be provided in the ROD for the Groundwater
Operable Unit  (OU3).

5.0  SUMMARY OF SITE CHARACTERISTICS

5.1  DEMOGRAPHY AND LAND USE IN THE AREA OF THE SITE

     The Vertac site covers approximately 192 acres on Marshall
Road within the city limits of Jacksonville, Arkansas, population
29,000.  Approximately 1,000 residents live within one mile of
the site with residential areas bordering the entire east and
south sides.   The west and northern sides of the site are bounded
by an industrial area and the Little Rock Air Force Base.

     The Vertac site is currently zoned for industrial use and
has been used for commercial/industrial operations for
approximately 50 years.   Land use zoning near the Vertac plant is
shown in Figure 3.   The area just south of the Vertac site,
between Marshall Road and the Missouri-Pacific railroad tracks,
south to West Main Street, is a residential area made up of both
single family homes and apartments.  The area immediately west of
the ra.L^oad tracks and north of West Main Street has recently
been developed and supports several light industries.  The area
between West Main  Street and South Redmond Road is commercial and
light industrial.  Just south of South Redmond Roau is
undeveloped land that includes the Jacksonville Sewage Treatment
Plant, DuPree Park, and Lake DuPree.  On to the south, the rest
of the area consists predominantly of irrigated rice fields and
woodlands.

     As discussed  in Section 4.0 above, EPA has evaluated the
past land use  for  the site, the current land use scheme  for the
area surrounding the site determined by zoning ordinances, and
has held discussions with City of  Jacksonville officials and
residents regarding land use.  Based on this evaluation, EPA has
concluded that the reasonably anticipated  future land use for  the
site is commercial/industrial.  Thus, EPA  derived  its site-
specific risk  assessment  based on  that reasonably  anticipated
future land use.
                                20

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       SCALE W FEET
       APPROXIMATE
Und Use Zoning Map

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 5.2   SOILS AND GEOLOGY

 5.2.1  Soils

      Soils in  the  area of  the plant are classified as the
 Leadvale-Urban land complex with a 1 to 3 percent slope.  The
 Leadvale  series soils  are  composed of moderately well-drained
 soils in  valleys,  formed mainly of loamy sediment and washed from
 uplands consisting of  weathered shale, siltstone and sandstone,
 such  as those  that underlie the site.  Leadvale soils are
 generally described as having moderately low permeability and a
 seasonally perched water table.  Tne Leadvale-Urban land complex
 consists  of areas  of Leadvale soils that have been modified by
 urban development.  Because of the extensive development and
 earth-moving activities at the site, natural soil characteristics
 have  been obscured.

 5.2.2   Geology

     The  site lies in  the transition zone between the Coastal
 Plain  and the Interior  Highla^s Physiographic Province.  The
 surficial geology of the Coastal Plain Province in the region
 surrounding the site is dominated by westward thinning wedge of
unconsolidated sediment consisting of the Tertiary Age Clairborne
Group, Wilcox Group,  and Midway Formation.

     The Clairborne Group and the Wilcox Group are
undifferentiated along  the fall line that occurs in the site
area.   The wedge onlaps the Rocks of Pennsylvanian Age lower
Atoka Formation, which dominate the geology of the Interior
Highlands Province in the region surrounding the site.
Quaternary alluvium and terrace deposits occur locally along
drainages in both provinces and are more common in the Coastal
Plain Province.  A generalized summary of the geologic formations
 surrounding the site is presented in Table 1.  A map of the site
geoloTy is presented in Figure 4.

     The contact between the Tertiary Age sediments and the
Pennsylvanian Age rocks occurs along a regional trend northeast
to southwest and is present in the area of the site.  On a local
 scale,  the trend of the contact depends on the current erosional
 surface and the paleotopographic surfaca of the Atoka Formation.
 The strike of the Wilcox Group Sediments and the Midway Formation
 tends  toward the northeast-southwest.  The dip of the sediments
 is low and oriented toward the southeast.  The Midway Formation
 was deposited  onto the irregular and weathered surface  of the
 Atoka Formation, which was folded and fractured during  the late
 stages of the  Alleghenian  orogeny.  The Atoka Formation was  later
 uplifted  and weathered. In the area of the  site, the strike of
 the beds  in the Atoka  Formation trends N70°W and dips about
 35°NE.  The Atoka  Formation outcrops along Rocky Branch Creek  on
 the western side of the property.

                                22

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    ERA
SYSTEM
rt
     y


     8
     o
     z
     LLJ
     U
     U



     3
SERIES


HOLOCENE
SUBDIVISION


ALLUVIUM
THICKNESS
(FEET)

0-50
LITHOLOGY




RED TO GRAY CLAY;
OCCASIONAt LY SiLTY TO SANDY
WATER SUPPLY


3ENERALLY NON-WATER
BEARING; DOMESTIC
SUPPLIES AVAILABLE
FROM BASAL UNITS
PLEISTOCENE





EOCENE




_ 	 • 	 	 	 	
PALEOCENE
__ 	 	 	 	
1
UPPER
CRETACEOUS
ALLUVIUM
AND
TERRACE
DEPOSITS
_ 	 	 	 	

CLAIBORNE
GROUP



WILCOX
GROUP

Q
1
-7 IU
uiZ

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o

w
J>
                                                                                                                                                                    Legend
                                                                                                                                                                           Quaternary
                                                                                                                                                                           Alluvium  Red to Gray Clay.
                                                                                                                                                                           Occasionally Silty to Sandy

                                                                                                                                                                           Terrace Deposits  Basal Sand and
                                                                                                                                                                           Gravel Overlain by Fine Sand.
                                                                                                                                                                           Silt an
 ^^_^ Tertiary
 K^""1 Wilcox Group - Orange-red to
 KaJl Red-brown Silty Sand to Silty Clay

 •^^j Midway Formation  Uyht Gray Cldy


        Pennsylvanian
 ra"5*l Atoka Formation - Interbedded
 rajl^J] Sandstones.  Siltstones and Shales

   j/  Stike - Slip Fault Indicating Relative
 -^^   Motion

 ''^   .Jormal Fault Indicating Dip Direction

Sources: C  Stone, Cabot Geologic Quadrangle
        Map. 1968

        C  Stone. Olmstead Geologic
        Quadrangle Map. 1968

        B  Haley and C Stone. Jacksonville
        Geologic Quadrangle Map. 1968

        C. Stone and B. Haley. fV.cAlmont
        Geologic Quadrangle Map. 1 968
                                                                                                                                                                             N-
                                                                                                                                                                                      w
                                                                                                                                                                               400
                                                                                                                                                                                 Seal* In FMt
                                                                                                                                                                            GEOLOGIC MAP OF THE
                                                                                                                                                                      JACKSONVILLE, ARKANSAS AREA

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 5.3  HYDROLOGY

 5.3.1   Surface Water

     Because of the potential  for  surface runoff to transport
 potentially contaminated  soils off of the site, previous remedial
 actions included the  installation  of sumps to collect the first
 flush of surface water runoff  from the central process area for
 treatment.  After treatment, this  water is discharged to Rocky
 Branch  Creek.  Runoff that exceeds the capacity of the sumps
 currently flows to the Rocky Branch Creek.  This ROD will in part
 address potentially contaminated sedimer'. j that bypass the sumps
 after they are inundated  by heavy  rains.  See Section 7.2, Storm
 Water Runoff Control.

     There are two major  drainageways in the area, Rocky Branch
 Creek,  and Bayou Meto, which is a  tributary to the Arkansas
 River.   Rocky Branch  Creek flows through the part of the site
 west of  the central process area.  Approximately 2 miles
 downstream,  Rocky Branch  Creek flows into Bayou Meto.

     Surface drainage ditches on the western part of the site
direct  local runoff westward toward Rocky Branch Creek.   An
earthen dam was constructed across the creek in the early 1950's
to form a cooling water pond that was used to supply non-contact
cooling water to the plant.

     At  its maximum extent, the pond extended to a distance of
about 1,000 feet north of the dam.   The pond was adjacent to the
north burial area.   The dam was removed and the cooling water
pond was closed in July 1985.  Rocky Branch Creek was diverted
 around the location of the former cooling water pond as a part of
the pond c3  sure.   The diversion is maintained today by an
 earthen dike along the eastern side of the creek.

     Surface water runoff from the western part of the central
process  area, including the central ditch that transects the
 central process area, is  contained in drainage ditches that
 divert  the initial runoff to sumps.  The sumps are connected to
 the wastewater treatment  plant, which uses activated granular
 carbon  to treat the water.

     Surface drainage ditches  in the northeastern part of the
 site direct runoff eastward toward a primary ditch that  lies
 along the western side of Marshall Road.  ,This ditch directs
 water toward Rocky Branch Creek south of  the site.

 5.3.2   Ground Water

     This ROD does not address the ground water  issue.   The
 Operable Unit 3 ROD,  scheduled for September  1996, will  address
 ground  water contamination.

                                25

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     Ground water  in the region  surrounding the site occurs in
both the overburden and the underlying bedrock.  The overburden
and bedrock are generally not considered as major sources of
ground water near  the site.  Ground water supplies in the region
are obtained from  the unconsolidated sands and gravels in the
Tertiary and younger Quaternary  sediments.  Most ground water is
produced from wells completed in the sands within the Wilcox
Group and basal sands and gravels within the Pleistocene alluvium
and terrace deposits.  Yields from these deposits can range up to
2,000 gallons per  minute (gpm).  Ground water in the
unconsolidated sediments is present in the primary intergranular
pore space.  Some  domestic ground ^ater supplies are obtained
from the Atoka Formation.  Yields can range up to 10 gpm.  Ground
water in the bedrock is present  in fractures and partings within
the rock.

     The hydrology in the area of the site is influenced by the
location of Rocky Branch Creek, the French drain,  the central
ditch, and the hydraulic characteristics of the overburden,
weathered rock, and bedrock.

5.4  REMEDIAL INVESTIGATION FINDINGS

5.4.1 Background

     Site investigations and remedial actions have been performed
at the site since 1978.   Figure 5 shows an overview of the
remedial action performed at the site to date,  mostly involving
the closing of a cooling water pond,  capping old landfills and
burial areas,  and the installation of a french drain leachate
collection system around the landfills and an on-site wastewater
treatment plant.  Hercules,  Inc., completed the RI for OU2 Phase
1 in December 1992 which addressed surface and subsurface soils,
shallow ground water,  and underground structures such as
underground utilities,  foundations,  curbs, pads and fuel storage
tanks.  The USTs have since been addressed.  Hercules, Inc.,
emptied these underground storage tanks (USTs)  and filled them
with grout.  The OU2 Phase 2 RI, completed in September 1995,
principally addressed deep ground water contamination and some
additional soil investigation in the northern part of the site.
Ground water has since been split off into a separate operable
unit (OU3) for the purpose of expediting the completion of the
soils and underground structures remediation effort and is not a
part of this ROD.

     The RI for OU2 has shown that the nature and levels of
contaminants found in the soils  at the site tend to parallel
particular process areas of the  plant.  The central process area
of the site has been divided into 10 subareas based on
operational activities  (see Figure 6).  They include  the
following:


                                26

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O

M
Ul
,
-1L.

JIP^ i .'/ '
'Jl!<« -^
|I*-'"'U
fc- I
\\*%%Ji- •:• H
{ *> '^ * A ' ") ^ v / 1
r, yJjBP"^ 'Ml '* y' J Excavated Surface Soils Area
im Asphalt-Capped Blow Out Area
fc%%) Scraped Areas
• -o- - — French Drain
•• Slurry Wall
Fence Line
miiiriii j Central Ditch
• < • Railroad
""•" Diversion Dike
•"•• •— • Clay Barrier Wall
Gunnlte-Covered
• Surface Water Sump
v /. / ' \ Buildings and Foundations
N
nr ^^ c
^
s
0 400 800 1200
Seal* In F«*t

Source: vertac Site Boundary and Pnotogiammeiric
Survey Prepared by Weil an 1 Associates. Inc
Projection: Arkansas Coordinate Syitem.
North Zone (NAD i 983|
AREAS OF PREVIOUS REMEDIATION
VERT AC SITE
JACKSONVILLE, AR

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Tl
M
O

?d
a

ON
                                                                                          ESTERflCATION
                                                                                            PLANT
      DALAPON
      PRODUCTION \  |
» 1L  AREA «.
                                                   EXISTING
                                                   QtORMATIOM
                                                   PLANT 9TE
                                         FORIO CHIOBNATION
                                             PLANT STE
                                                                                                    RECYOI UQUOR
                                                                                                    STORAGE AREA
                               FORMULATIONS
                                  AREA
                                                                                                                                       2.4,5-T
                                                                                                                                       PRODUCTION
                                                                                                                                       AREA
                                                                                                                                                    PRODUCTION  ARIAS
                                                                                                                                                    CENTRAL PROCLSS
                                                                                                                                                    BOUNDARY
                                                                                                                                               VERTAC SITE PROCESS AREA

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 •    Maintenance Area  - used  for equipment repairs  and  storage of
     equipment, parts, and some raw materials.

 •    Formulations Area - used for the storage of raw and finished
     products  (large warehouse and some process vessels).

 •    Former Chlorination Plant Area - used in manufacturing 2,4-D
     herbicide.

 •    Existing Chlorination Plant Area - built in early  1980's and
     replaced old Chlorination plant.

 •    Esterification Plant - used to add alcohols to increase
     solubility of the herbicide to water.

 •    Dalapon Production Area  - used in manufacturing dalapon
     (1,1,1-trichloropropionic acid).

 •    Recycle Liquor Storage Area - used for the storage of
     manufacturing materials  such as recycle liquor, caustic
     soda, and spent solvents.  Currently used to store drums
     generated by ongoing site activities.

•    Recovery Plant - used in the treatment of process wastes.
     2,4-D waste were recovered,  and drums containing 2,4-D were
     washed.

•    2.4.5-T Production Area -  used in manufacturing of 2,4,5-T
     herbicide.

•    Acid Plant - chlorophenols were reacted with acetic acid and
     monochloroacetic acid to form phenoxyacetic acid herbicides.

     The area around the Regina Paint Building,  located in Parcel
1 (north area of the site)  is included in OU2 because the
building was used to store empty drums that had been used to
handle or store wastes from the manufacture of 2,4,5-T.

The media addressed in the OU2 RI include:

          Surface soils
          Subsurface soils
          Tetrachlorobenzene  (TCB) spill area
          Underground utilities
          Building Foundations and Curbed Areas
          Underground Storage Tanks  (USTs)

     The USTs have since been addressed.  Hercules, Inc.,  emptied
 these USTs and filled them with grout.  Therefore,  they will  not
 be addressed in this ROD.
                                29

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Other media that will also be addressed  in this ROD  include;

     •    Off-site  soils  from Rocky Branch Creek flood plain
           (1990 ROD).

     •    Sludge from the Old Sewage Treatment Plant sludge
          digester,  and sediments from the interceptor line.
           (1990 ROD).

     •    Bagged soils excavated from residential yards
           (1993 ROD).

     Remediation of  the off-site soils, sludges from the off-site
sewage digester and  sediments from the interceptor line, and
bagged soils from a  residential removal action were originally
addressed by EPA as  response elements in previous ROD'S and
removals.  However,  because of the similarities of these media,
and the wish to Lreat similar media In a consistent manner, EPA
now will address these media with the on-site soil media.

     The ROD for the off-sit^ area,  dated September 1990, called
for the excavation and incineration of soils in the flood plain
area along Rocky Branch Creek that had a 2,3,7,8-TCDD
concentration greater than 1 ppb.  The estimated volume of flood
plain soils is approximately 4,100 cubic yards.  The off-site ROD
also called for the  incineration of sludges removed from the
digester at the Old Sewage Treatment Plant and sediments from the
interceptor line.   The approximate volume of sludges from the
digester is 800 cubic yards and the sediments from the
interceptor line is about 2 cubic yards.   The ROD for OU1
deferred the treatment decision for the bagged soils removed from
residential yards as a part of a removal action in 1990.  The
total volume of bagged soil is estimated at 2,770 cubic yards.

5.4.2 Sampling Results for Surface S«ils

     During the period between 1989 and 1992 approximately 461
grids were established for the purpose of determining the level
of contaminants present across the site.  EPA, IT Corporation,
Hercules, Vertac Site Contractors, and Weston  (contractor for
Hercules) were principally responsible for the collection of this
information (see Figures  7, 8, and 9; early grid sampling,
surface grid locations in the central process plant  area, and
surface soils sampling outside the central process plant area,
respectively).

     Over 180 grids  were  sampled under the OU2 Phase 1 RI.  The
majority of the grids were located in the central process  area
and were approximately 5,000 square feet.  These grids were
sampled for 2-chlorophenol, 4-chlorophenol,  2,4-dichlorophenol,
2,6-dichlorophenol,  2,3,6-trichlorophenol, 2,4,5-trichlorophenol,
2,4-D, Silvex, 2,4,5-T, and 2,3,7,8-TCDD.    Grids  outside  the

                                30

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	1  U S Environmental Protection Agency Surface
 «>' I  Sol Samplng Grtd and Number
	'  Nuttoera ftx EPA Grteh and Grab S*mpto
      Range Item 001 Tnrou/i 282

 V   US EiMfonmental ProtKDon Agency Stxtoce
      Grab Sampling Location and NunDe<

      Hrtrmjoonal Technology Surface Sol Sampkng I
      Grtd and Nunntxr
      NurOen tor mtemaDonal Tecnnology Grids
      Range from 800 Tnrougn 820

H      Venae Sat Canracion Surface Soil Samplng
      Grid and Number Symbol Represents Grab
      Samptng Location and Number
      Number* tor Venae Ske Contractor! Grids
      Range from 900 Tnrougn 949

 X   Venae SKr Contractors  Surface SoU Grab
      Sampftng Locabon and Number

•      GndJ VWiere Elevated ConcennaDons
      t>20 ppb) of 2.3.7.8-TOX) Were Found

 ~    Central Process Area Boundary

 	Property Boundary
            250
                         500
                                       750
 Source    Wmc Ste Boundary «nd FYioaDQrammccnc
         Survey Prepared by Wca *nd AUOCIMH. me
    QRID8 FROM PREVIOUS SURFACE
   SOIL SAMPUNQ 8URROUNOMQ THE
        CENTRAL PROCESS AREA
              VERT AC SITE
  	JACKSONVILLE, AR	

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                                 CPtTKAl MOCtSS ««» BOUNWr	
                                  ~~"=    ""
                                                                                                                                                    I	.  WESTON Surface Son Sampang Odd and
                                                                                                                                                      "  I  Nuiroer Numbers for WESTON Gndj «nd
                                                                                                                                                           Grab Samples Rang* from 400 Through 5«5
                                                                                                                                                           WESTON Surface Son OcaD Sampung
                                                                                                                                                           Locaoonand NumtMr
                                                                                                                                                     556
                                                                                                                                                      (Tj    WESTON Surface SON Sampling. Location Wltnn
                                                                                                                                                           ttie Blow Out Afea
                                                                                                                                                       ^  ;  Environmental PrattcOon Agency
                                                                                                                                                           Surface Son Sampano end and Numoet
                                                                                                                                                       ~ ~— Central Proccu Are* Boundary
•541T54T-  550  bbl
                                                                                                                                                    Source:    Veruc Site Boundary and Photogrammetric
                                                                                                                                                             Survey Prepared by West and Aisociatci. inc
                                                                                                                                                        SURFACE SOIL SAMPLING GRIDS
                                                                                                                                                       AND GRAB SAMPLING LOCATIONS
                                                                                                                                                     WITHIN THE CENTRAL PROCESS AREA
                                                                                                                                                                  VERT AC SITE
                                                                                                                                                               JACKSONVILLE, AR

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Ti
PI

 D
              Inul No. 2
                                                                    JSL
                                                                     No. 2
                                                                                                                                                                  —— Outline of Grids Outside the Central Process Area

                                                                                                                                                                   Q  WESTON Surface So* Samomg Odd and
                                                                                                                                                                        Number. Numbers for WESTON Gods and
                                                                                                                                                                        Grab Samples Range from 400 Through S85
                                                                                                                                                                     »4t
                                                                                                                                                                    °   WESTON Surface So* Grab Sampttig Location
                                                                                                                                                                        and Number

                                                                                                                                                                    •"* WESTON Surface Soil Sampling Location WWnn
                                                                                                                                                                        me Blow Out Area

                                                                                                                                                                  	Central Process Area Boundary

                                                                                                                                                                  	Property Boundary
                                                                                                                                                                              400
                                                                                                                                                                                            800
                                                                                                                                                                                                         120
                                                                                                                                                                                 Scatoln F««t
                                                                                                                                                                    Source:    Venae Site Boundary and Photogrammetnc
                                                                                                                                                                            Survey Prepared by U/eu and Associates, me
                                                                                                                                                                        SURFACE SOIL SAMPLING GRIDS
                                                                                                                                                                     OUTSIDE THE CENTRAL PROCESS AREA
                                                                                                                                                                                 VERTAC SITE
                                                                                                                                                                               JACKSONVILLE, AR

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central process area are approximately 40,000 square feet and
were screened for 2,3,7,8-TCDD only, because these areas were
outside of known production operations.  Eleven samples were
collected from a series of 11 uniform nodes within each grid.

     From those 11 samples three composites were made and
analyzed for 2,3,7,8-TCDD.  Essentially all areas exhibiting
elevated TCDD concentrations are located in the central process
area, and relative concentrations of chlorophenoxyherbicides and
chlorophenols measured in the surface soils paralleled dioxin
concentrations.

     Most of the unsampled areas of the site were generally in a
downstream direction from sampled areas exhibiting TCDD
concentrations of 2 ppb or less.   Tabla 2 depicts the maximum and
average concentrations for the contaminants of concern (COC's)  at
the site.
                            Table 2.
CHLOROPHENOLB
2-chlorophenol
4-chlorophenol
2 , 4-dichlorophenol
2 , 6-dichlorophenol
2,3, 6-trichlorophenol
2,4, 5-trichlorophenol
2,4, 6-trichlorophenol
CHLOROBEN2ENE8
Trichlorobenzene
CHLOROPHENOXYACIDS
2,4-D
Silvex
2 , 4 , 5-T
MAXIMUM CONG.
3 ppm
o . 12 ppm
360 ppm
15 ppm
0.73 ppm
270 ppm
79 ppm

17,000 ppm

5,500 ppm
290 ppm
710 ppm
AVERAGE CONG.
1.9 ppm
not computed
6.9 ppm
0.54 ppm
0.54 ppm
2.0 ppm
3.5 ppm

not computed

191 ppm
12.4 ppm
23.1 ppm
     TCDD concentrations at the site ranged between non-detect to
2,800 ppb.  The highest concentrations of TCDD found in surface
soils at the site were in the following areas (note: TCDD
concentrations are reported as the 95 percent upper confidence
limit for each grid sampled in an area):
                                34

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 Blow  Out Area  -  For the seven grids sampled  in this area
 TCDD  concentrations ranged between 0.25 ppb  for the least
 contaminated grid to  660 ppb for the most contaminated grid.

 The dioxin  in  this area is associated with occasional
 releases or "blow outs" during facility operations from the
 reactor vessel when the control of the chemical reactions
 was not maintained.   After such a release, the solidified
 2,4-D and 2,4,5-T was scraped from the ground and replaced
 with  a thin layer of  clean fill material.

 East  Drum Storage Field Area - TCDD concentrations for this
 area  ranged between 7.3 ppb and 120 ppb.

 The east drum  storage field can be subdivided into two
 distinct areas.  The  first area includes the drainage grids
 along the northern side of the site entrance road.  Dioxin
 in this are^ was most likely transported there from the blow
 out area.   The second area is located in the western part of
 the drum field.  Soil contaminants are most likely related
 to spillage from, the drum storage operations.

Main Boiler House Area - TCDD concentrations in this area
ranged between 0.39 ppb and 1,270 ppb.

This area acted as a sediment retention basin, and since it
 is located downslope from the blow out area,  TCDD is likely
present from sediment migration from the blow out area.

Area East of the Main Boiler House - TCDD concentrations in
this area ranged between non-detect and 98 ppb.

This area is down slope from the main boiler house.
Therefore,   the TCDD may have originated at the blow out area
 and migrated with sediments from the main boiler house area.

Area of the Existing  and Former Chlorination Plants - TCDD
 concentrations in this area ranged between 22 ppb and
 2,800 ppb.

 Portions of this area were used to dry 2,4,5-T, and TCDD is
 suspected to be present as the result of these drying
 practices.

 Maintenance Area - TCDD concentrations in this area ranged
 between 4.8 ppb  and 57 ppb.

 Previous overpacking  of leaking drums  in this area may have
 contributed to the TCDD found in this  area.
                           35

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 5.4.3   Subsurface  soils

     During the RI, numerous subsurface soil samples were taken
 from soil borings  throughout the site.  The purpose was to
 determine whether  significant sources of contamination existed
 below the surface  soils which could potentially migrate and
 degrade water quality.  Analyses were performed on these samples
 to quantify the concentrations of chlorophenols,
 chlorophenoxyherbicides, and TCDD in these soils.

     Of more than  90 samples taken and analyzed for TCDD, only 5
 vere greater than  20 ppb.  The ra-ge of the 5 samples were
 between 20 ppb and 310 ppb.  These elevated levels were all
 obtained in different borings and at different depths.

     The vertical extent of TCDD at depths greater than 36 inches
 appears to be related to areas where burial occurred such as the
 chlorination area, or where sediments may have accumulated such
 as the main boiler house area.   The vertical extent of TCDD
 between 12 and 36 inches is limited to areas where the land
 surface may have been built up during subsequent site activities,
 such as the blow out area,  and south of the chlorination area.
The data suggest that TCDD contamination between 12 and 36 inches
of soil depth is not the result of downward migration of TCDD
from the surface.

5.4.4  Tatrachlorobanzanc Spill Araa

     The tetrachlorobenzene (TCB)  spill area resulted from an
accidental release of TCB from a railroad car.   Molten TCB filled
the low area between the railroad tracks and penetrated into the
soils pore spaces under the tracks before crystallizing.   The
spill area is about 830 square yards,  based on where TCB was
observ	   The western limit was noi found because access for
excavation was impeded due to physical obstructions at the site,
e.g.. building foundations, etc.  The vertical extent was also
not determined at the time of the RI for similar rtasons.  The
horizontal and vertical extent of the TCB contamination will be
determined during the remediation process.   TCB was found at
 concentrations ranging between 200 ppm and 1,700 ppm in pit
 samples at depths of 32 to 34 inches below ground surface.

 5.4.5  Underground Utilities

     Because TCDD tends to adsorb to clay-rich and organic-rich
 soils and due to the potential for the compound to migrate with
 these sediments if they are transported by water flow, samples
 were taken from several underground utility lines  including  the
 industrial and sanitary sewer lines as well as surface water
 sumps.  Pressurized piping  (natural gas lines and  public water
 lines)  were not sampled since there was no accessible point  of


                                36

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entry to these  lines at the site due to the fact that they were
under constant  pressure.

Five samples were collected for each structure.

•    Industrial Sewer - sediment samples showed the highest TCDD
     concentrations of any underground utilities, with the
     concentrations ranging between 7.3 ppb and 79 ppb.

•    Surface Water Sumps -  sediment samples for TCDD from the
     surface water sumps ranged between 8.4 ppb and 18 ppb, and
     are generally consistent witr the soil concentrations within
     the central process area.

•    Sanitary Sewer - the lowest concentrations of TCDD were
     found in the sanitary sewer system and ranged between non-
     detect to  4.1 ppb.  Measurable concentrations of TCDD were
     found in the on site sewer lines extending southeastward
     from the central process area.  No TCDD was found in the
     currently  active portions of the sanitary sewer which
     extends southward of the site.

•    Porous Bedding Material around Underground Utilities - there
     is no field information or design drawings available that
     indicate whether or not granular material was used for
     bedding of these lines.  Therefore,  the potential for
     preferential flow of ground water in bedding material around
     the outside of utility piping may exist at the site.

5.4.6  Underground Storag* Tanks (USTa)

       A survey of the USTs for the site indicated the presence
of 5 tanks, with capacities ranging between 250 gallons and 1,000
gallons.  All 5 tanks have previously been used to store gasoline
or diesel fuel.  The approximate volume of residual fuel in the
tanks is as follows:

     UST1 -  42 gallons
     UST2 -  57 gallons
     UST3 -  17 gallons
     UST4 -  35 gallons
     USTS - 208 gallons

     Since the  preparation  of the  RI and FS, all 5 tanks have
been pumped dry and backfilled with grout  containing a mixture of
sand, cement, and flyash by Hercules,  Inc.  Subsurface soil
samples around  the UST's for petroleum hydrocarbons,  lead,
benzene, toluene, and  xylenes do  not  indicate  the presence of  any
significant leaks from these USTs.
                                37

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5.4.7  Off-ait* Rocky Branch Creek and Bayou Meto Flood Plain
       Soils

     One element of the  1990 Off-site ROD called for the
excavation of  flood plain areas that are currently zoned
residential where the TCDD concentrations are greater than 1 ppb.
Approximately  4,100 cubic yards of soils are estimated to contain
dioxin above the cleanup goal.  The highest TCDD concentration
found in this  area was 9.6 ppb.  The remedy in the 1990 ROD also
called for these soils to be brought back to the Vertac site for
on-site incineration.  EPA subsequently deferred the treatment
requirement for these soils such that all site soils could be
handled in a consistent  manner.  The remediation of these soils
has now been incorporated into this ROD.  For more information
see the Vertac Superfund Site Record of Decision for Off-site
Areas, September 1990.   The final disposition of the flood plain
soils is discussed in Section 9.0 of this document.

5.4.8  Residential Bagged Soils

     In 1988, EPA signed an Administrative Order on Consent (AOC)
with Hercules, Inc., requiring it to remove soils from
residential yards south  of the Vertac plant where TCDD was found
above 1 ppb,  and a drainage ditch on-site in the area of the
residences.   Approximately 2,770 cubic yards of soils were bagged
and placed in a storage  facility at the site.   Chlorinated
phenols,  chlorinated benzenes, and chlorinated phenoxyherbicides
were present at non-detect to low concentrations.  TCDD was
detected in all samples  at levels ranging from 13  ppb to 55 ppb.
The 1993 ROD for Vertac On-site Operable Unit 1 (above ground
media)  deferred the treatment requirement for these soils so that
all site soils could be  handled in a consistent manner.  The
remediation of these soils has now been Incorporated into this
ROD.  For more information see the Record of Decision, Vertac
Superfund site - Operable Unit 1, June 1993.  The final
disposition of the residential soils Hercules, Inc., excavated as
part of a removal action is discussed in Section 9.0 of this
document.

5.4.9  Sludges and Sediments from the Old Sewage Treatment Plant
       Digester

     One element of the  Record of Decision  for the Vertac Off-
Site Areas, dated September 1990, called for cleanup and
demolition of  the old Sewage Treatment Plant.  As a part of that
ROD, approximately 890 cubic yards of sludge from the  sludge
digester was removed in  1994 using a vacuum pumping system.   The
sludge was then transported back to the Vertac site for on-site
incineration.  The maximum concentration of TCDD found in the
sludge digester sediments was  12.5 ppb.  Another element  of  that
ROD called for the removal of  sediments from  a sewer  interceptor
line, which physically connected the Old Sewage  Treatment Plant

                                38

-------
 to  the Vertac facility.   Approximately  2  cubic yards of  sediments
 were  removed from the interceptor  line  in 1994 and transported
 back  to the Vertac site  for  on-site  incineration.

      EPA subsequently deferred the treatment requirement for
 these sludges/sediments  so that all  such  site materials could be
 handled in  a consistent  manner.  As  discussed at Section 4.0
 above,  those media are considered  to constitute low level threats
 due to the  fact that  the average level  of  dioxin contamination in
 those media is well below 5,000 ppb, which is three orders of
 magnitude above the site's 5 ppb cleanup  level identified in the
 risk  assessment.   See EPA's guidance on low level and principal
 threats  cited at  Section 4.0, OSWER  Directive No. 9380.3-06FS.
 Therefore,  the remediation of these  sludges/sediments has now
 been  incorporated into this ROD.   For more information see the
 Vertac Superfund  Site Record of Decision,  Off-Site Areas, dated
 September 1990.   More discussion on  the final disposition of
 these sludges a^.J sediments is included in Section 9.0 of this
 ROD.
6.0  SUMMARY OF SITE RISKS

6.1  RISK ASSESSMENT DESCRIPTION

     An evaluation of the potential risks to human health and the
environment from site contaminants associated with Operable Unit
2 media was presented in a separate document called the OU2
Baseline Risk Assessment.  The baseline risk assessment was
completed in concert with the development of the RI/FS.  The
purpose of the baseline risk assessment is to evaluate the
potential risk to human health and the environment from site
contaminants prior to remediation.  The results from the baseline
risk assessment are used to establish cleanup goals for the
contaminants at the site that pose the greatest risk.  The OU2
baseline risk assessment is divided into two main sections, the
Human Health Risk Assessment and the Ecological Risk Assessment.


     In general, a risk assessment is a procedure which uses a
combination of facts and assumptions to estimate the potential
for adverse effects on human health and the environment from
exposure to contaminants found at a site.  The environmental or
ecological risk assessment is conducted to determine if there are
any current or potential impacts on ecological receptors
attributable to the unremediated site.  Human health risks are
determined by evaluating known chemical exposure limits and
actual concentrations at the site as  identified during the RI
sampling activities. In the risk  assessment, carcinogenic risks
 (from chemicals that are known or believed  to  cause cancer)  and
non-carcinogenic health risks  (from chemicals  that are not known


                                39

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to cause cancer, but  can cause a range of other illnesses) are
calculated.

6.2  IDENTIFICATION OF CHEMICALS OF CONCERN

     This section summarizes the site data that were used to
evaluate potential health risks to human and nonhuman receptors.
The substances that were considered for each exposure medium
include the following:

     • Surface Soil   -  Chlorophenols
                         Chlorophenoxyherbicides
                      -  2,3,7,8-TCDD

     • Ground Water   -  Acetone
                         Chloroform
                         Chlorophenols
                         Chlorophenoxyherbicides
                      -  Methylene Chloride
                      -  Nitroaromatic explosives
                         Priority pollutant metals
                      -  2,3,7,8-TCDD
                      -  Tetrachlorobenzene
                      -  Toluene

     • Surface Water  -  Chlorophenols
                         Chlorophenoxyherbicides
                      -  2,3,7,8-TCDD
                      -  Toluene

     An effort was made to focus the risk assessment on those
chemicals that are of greatest concern for a given medium.
Chemicals that were infrequently detected in a medium that was
sample^ systematically, unless there was evidence for a "hot
spot",  were eliminated (see U.S.  EPA guidance, 1989 (b)).

     Tables 3, 4, and 5 present the data summary for substances
of potential concern for each medium and their frequency of
detection.   Please note that the terminology used in Tables 3
through 5 is consistent with the terminology set out in the EPA
guidance document "Supplemental Guidance to Risk Assessment
Guidance for Superfund (RAGS): Calculating the Concentration
Term," OSWER Publication 9285.7-081, 1992.  Therefore, the term
"Upper 95% Confidence Limit of the Geometric Mean" used in Tables
3 through 5 actually means the upper 95% confidence limit of  the
arithmetic mean.  However, when evaluating the combined risk
posed by all the COC's at the site, dioxin contributed  over 99
percent of the total  risk.
                                40

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                                              Substances of Potential Concern in Soil
                                                  Data Summary — All Samples
W

UJ
             Substance

     2-Chlorophenol

     2,4-D
     2,4-Dichlorophenol
2,6-Dichloropbenol



quency
e
of
ection*
>/138
2/127
7138
1/138
3/124
5/129
/1.146

1/1
J/137
J/136

Range of
Sample
Quantitation
Limits
(mg/kg)b
0.33-18
0.023-4.2
0.042-18
0.33-18
0.012-670
0.012-670
0.01-4.5
(ng/g)
NI
0.33-3.8
1.7-91


Range of
Detected
Concentrations
(mg/kg)b-<
0.047-3.0
0.0053-5,500
0.034-360
0.066-15
0.0012-290
0.0016-710
0.04-2,200
(ng/g)
670,000
0.033-270
0.047-79

Adjusted
Geometric
Mean
Concentration
(mg/kg)b
0.34
580
3.0
0.54
28
63
5.3
(ng/g)
NA
1.9
2.6
Upper 95%
Confidence Limit
of the Geometric
Mean
Concentration
(mg/kg)b
0.39
3,100
5.0
0.66
110
250
9.2
(ng/g)
NA
3.0
3.4
      Tetrachlorobenzened

      2.4.5-Trichlorophenol

      2.4.6-Trichlorophenol

    NA = Not applicable
    M  = Information was not available
                             r  i   tinns at which the substance was detected to the total number of sampling locations, with the exception of
    •Ratio of the number of sampling locauon^ ^ 2,3,7,8-TCDD is the ratio of the number of composite samples in which 2,3,7,8-TCDD was detected to
     237 8-TCDD. The frequency ot aete
     the total number of «>mP°s'%Jlgg^mch is expressed in units of ng/g.         .
    •"""•- the exception of 2,3, /,»-»cr~'  ..  low the minimum sample quantitation limit.
          .  ...  ._....!—k ore esiimdicu       . fc,,^^rt;nn i M
                           i the hot spot analysis

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                                             Substances of Potential Concern in Groundwater
                                                    Data Summary — Atoka Formation
I
M
                                                                                                                   Upper 95% Confidence
                                                                                                                   Limit of the Geometric
                                                                                                                     Mean  Concentration
                                                                                                                           (mg/L)b
                                                                Range of Detected
                                                                 Concentrations
                                        (Range of) Sample
                                       Cuantitation Limit(s)
Adjusted Geometric
Mean Concentration
                         Frequency of
                           Detection*
        2-Chlorophenol
        4-ChiorophenoI
                                                                          0.00015-1,640
2,4-D
•MVM«
2.6-D
-•
2.4-Dichlorophenoj

2.6-Dichlorophenol
•.   —^•••^•^
Methylene chloride
^^•^^^•^•M
Phenol
                                             0.005 0.06
                                             _-——  11.^^
                                             0.005-0.82
                                                     0.005-0.063

                                                        0.005

                                                     0.0005-0.54
                                                     —i       "• -
                                                    0.00013-0.007
                                                        >«^BI^"~
                                                        0.005
                                                                            0.85-2,080
                                                                              (ng/L)
                                               0.01-1.8
                                                (ng/L)
2,3,7,8-TCDD
         Tetrachlordbenzene
         Toluene
         2 3 6-Trichlorophenol
         2 4.5-Trichlorophenol
                                              0.005-0.82
                                               ..   i  '••••
                                               0.005-4.1

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r1
«
-p-
o
o
3
             Substance
      Organic* (continued)
      2.4.6-Trichlorophenol
Inorganics
Antimony
Arsenic
Chromium
Copper
Lead
Mercury
Nickel
 Silver
 Thallium
 Zinc
                                           Substances of Potential Concern in Groundwater
                                                  Data Summary —  Atoka Formation
                                                               (continued)
                               Frequency of
                                 Detection*
38/80

 3/26
 2/26
j/26
 3/26
 2/26
 9/26
 10/18
 11/26
 4/26
 22/22
(Range of) Sample
Quantitation Limit(s)
(mg/L)b

0.005-0.82
Range of Detected
Concentrations
(mg/L)b*

0.001-94
Adjusted Geometric
Mean Concentration
(mg/L)J

2.1
Upper 95% Confidence
Limit of the Geometric
Mean Concentration
(mg/L)b

9.9

0.060
0.010
C.010
0.025
1,003
0.0002-0.00025
0.040
0.010
0.010-0.10
0.020'
0.022-0.029
0.0036-0.013
0.0020-0.012
0.0066-0.025
0.0036-0.011
0.00022-0.00076
0.011-0.109
0.0034-0.0094
0.010-0.100
0.011-0.270
0.029
0.0053
0.0050
0.013
0.0018
0.00023
0.032
0.0056
0.031
0.043
0.030"
0.0056
0.0055
0.014
0.0021
0.00031
0.049
0.0060
0.060
0.063
                                                      ,5, detected during one or more sampling rounds to the total number of wells sampled.
                   f
"With the exception of
"Exceeds the maximum reported
'Sample quantitation limits were not
                                                                                   ......
                                         concentrations, usually below the minimum sample quantitation limit.
                                                   contract-required detection limit/instrument detection limit (CRQL/IDL) is indicated.

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                                    Substances of Potential Concern in Surface Water
                                         Datp. Sumi  ary — All Sample Locations
r1
M
     Substance
2-Chlorophenol
4-Chlorophenol
2,4-D
2,6-D
      2,4-Dichlorophenol
      2,6-Dichlorophenol
      Phenol
      Silvex
      2,4.5-T
      2.4,6-T
      2,3,7,8-TCDD

      Toluene
Frequency of
 Detection'
    6/6
    6/6
    6/6
    6/6
    6/6
    6/6
    6/6
    6/6_
    6/6
    6/6
    3/6
.ange of
Sample
antitation
Limits
(^/L)b
0.8-5
1.1-5
2-5
2-5
1-5
0.5-50
0.6-5
1-2
1-2
1-2
2-10
(ng/L)
5-21
Range of Detected
Concentrations
(^g/L)b'c
0.85-460
1.2-8,800
2.9-17,000
2.0-5,400
1.8-6,800
1.0-1,100
0.60-620
1.0-1,100
1.7-3,300
1.1-11,000
2.0-12
(ng/L)
0.022-3,900
Adjusted
Ge ^metric
Mean
Concentration
(^g/L)b
18
230
1,100
500
200
13
24
84
200
240
1.6
(ng/L)
52
Upper 95%
Confidence Limit
of the Geometric
Mean
Concentration
(^/L)b
420
480,000d
2,700,000d
45,000d
290,000d
350
4,600d
18,000d
44,000"
33,000d
1.9
(ng/L)
9,900d

-------
r1
w
o
o
3
                                           Substances of Potential Concern in Surface Water
                                                Data  Summary — All Sample Locations
                                                               (continued)

.ange of
Sample
antitation
Limits
(/WL)b
1.2-50
1.5-5
1.1-5



Range of Detected
Concentrations
(A€/L)b'c
2.0-69
1.6-5,000
1.7-1,500

Adjusted
Geometric
Mean
Concentration
(/4S/L)b
4.1
130
29
Upper 95%
Confidence Limit
of the Geometric
Mean
Concentration
(/^g/L)b
12
350,000"
2,500d
•Ratio of the number of
"With the exception of 2,.,,.,- - ----•
Includes "J" values, which are estimated below
«Emb the maximum reported concentrate
                                   I   rinns at which :ae substance was detected to the total number of sapling locations.
                                     11     ^       ed •„ ^ of ng/L.

-------
 6.3  HUMAN HEALTH RISK ASSESSMENT

 6.3.1   Summary

     A  baseline risk assessment was conducted for the Vertac site
 where risks were evaluated using current site conditions for
 three potential receptor scenarios:  teenage trespasser, current
 unprotected worker, and future unprotected worker.  Exposure
 routes  assessed for the trespasser scenario included dermal
 contact with soil, incidental ingestion of soil, contact with
 surface water, and inhalation of particulates or vapors.
 Exposure routes accessed for the current unprotected worker
 scenario included incidental ingestion of soil, dermal contact
 with soil, dermal contact with surface water and water from the
 production outfalls at the site, and the inhalation of airborne
 particulates and vapors.  A future unprotected worker was assumed
 to be exposed to the same substances of concern as the current
 unprotected worker uith the addition of the ingestion of site
 ground water.  It should be noted, however, that the cleanup goal
 proposed by EPA for the site does not consider that a future
 worker will be consuming grov-^ water.  Public water supplies are
 readily available and the future use of site ground water as a
 drinking water source will be prohibited through institutional
 controls.

 6.3.2  Exposure Assessment

     The potentially exposed populations and the pathways through
which they could be exposed for current and future site
 conditions are discussed below.

 Current and Future Land Use

     As discussed in Section 4.0 above, EPA has evaluated the
 past land use for the site, the current land use scheme for the
 area surrounding the site determined by zoning ordinances, and
 had discussions with City of Jacksonville officials and
 residents.  EPA has concluded that the reasonably anticipated
 future  land use for the site is commercial/industrial, which is
 consistent with past land use and the current zoning for the site
 area.   EPA's risk assumption for OU2 presupposed that future land
 use would be commercial/industrial, and so EPA derived the site's
 cleanup level of 5 parts per billion  (ppb) toxicity equivalents
 (TEQ) for dioxin due to the fact that a commercial/industrial
 human exposure scenario assumes that a worker would be exposed to
 post-cleanup dioxin levels over a 40 hour per week period.  This
 worker  exposure scenario additionally  is protective of a
 trespasser or a passerby, both of whose exposure period would be
 less than that of a site worker.  In deriving the 5 ppb dioxin
 cleanup level, EPA assumed that the pathways of exposure  to  site
 contaminants likely for future site workers would be  soil
 ingestion, dermal absorption from soil, soil inhalation,  vapor

                                46

-------
 inhalation or dermal absorption from volatilization of  surface
 water.   In addition,  EPA assumed a  soil  inyestion and dermal
 absorption pathway from soil  for a  trespasser  or  an occasional
 passersby.

      Thus,  EPA derived its  site-specific risk  assessment  based on
 that  reasonably anticipated future  land  use.   The land  occupied
 by the Vertac facility is zoned commercial/industrial.  While
 there are  no  manufacturing  operations at the site,  it is
 reasonably anticipated that future  use could include  commercial
 development.   Continuing activities include general maintenance
 of the plant,  maintenance of previous remedies, and operation of
 a wastewater  treatment plant by PRP site maintenance  workers.
 Deed  restrictions  are  in place  that will prevent  future
 residential development of  the  site.  Additional  deed
 restrictions will  be sought to  limit future commercial
 development of portions of  the  site that will contain waste
 disposal areas and are otherwise encumbered by long terr.
 remediation and perpetual operation and  maintenance activities.

     The land  located  west  and  north  of  the plant is  also used
 for commercial/industrial purposes.   Residential areas are
 located directly east  and south of  the plant.

     To assess  the current  and reasonably anticipated future land
use,  four receptors were evaluated:   A trespasser, a passerby, a
current unprotected worker,  and a future unprotected worker.
Trespassers and workers are the most  likely future receptors at
the site and represent  those individuals with the highest
potential for  exposure  to site related substances of  concern.

     A trespasser  could enter the site unnoticed by either
climbing or crawling under  one of the fenres either currently or
 in the future.  A  teenager  between  12 and 18 years of age was
evaluated for  this scenario.

     A passerby could  walk  by the east side of the site along
Marshall Road  in the future.  A teenager between  12 and 18 years
 of age was evaluated for  future exposure using this scenario.
Although any exposure  is  considered remote using  this future
 scenario,  it was evaluated  since the strip of property  along the
 west  side  of Marshall  Road  may  eventually be unrestricted and
 without a  fence, allowing for future commercial/industrial
 development.

      Current  and future worker  scenarios were  also evaluated.
 Because this  site  is  zoned  commercial/industrial,  a maintenance
 worker is  the individual who has the greatest  potential to
 contact on-site media  on a  regular  basis, both currently  and in
 the future.
                                47

-------
 Potential  Exposure  Pathways

 Trespasser

      It  is possible for  a  trespasser to be exposed to  substances
 of  concern on  the site through contact with soil, surface water,
 and air.   Potential soil exposure routes include dermal contact
 and incidental ingestion of soil.

      Of  the on-site surface waters, a trespasser is most likely
 to  come  into contact with  Rocky Branch Creek, which is located
 within the western  margin  of tlie site.  Due to the shallow nature
 of  the creek,  with  a depth of approximately 1 foot, only dermal
 contact  was evaluated.   The potential for a trespasser to come
 into contact with outfalls that flow to Rocky Branch Creek was
 considered to  be unlikely, due to the fact that they flow only
 during periods of high rainfall.

      The trespasser  could  also be exposed to chemicals of concern
 through the inhalation of  airborne substances originating from
 surface soil and surface water (particulate and/or vapor).

     The potential for a trespasser to become exposed to site
ground water was considered to be remote.   Even if ground water
were to be used on the site in the future,  it is likely that the
ground water would be used only after treatment.  Thus, this
exposure pathway was not evaluated.

Casual Passerby

     A casual passerby was considered for possible exposure to
 site related contaminants along the east side of the site
adjacent to Marshall Road,  since the existing fence located at
the pi ^erty boundary will be moved' to the west after remedial
action is complete so as to minimize the areas of the site that
will be restricted  in that fashion.   EPA will not be certain of
precise fence  locations until the remedial design phase of the
OU2 remediation.  However,  a casual passerby will have no actual
exposure after remediation since there is no complete pathway.
 If the remote possibility  is considered for contact of the
passerby through dermal  contact: and incidental ingestion similar
 to a  trespasser, this would be a conservative assumption.

      After remedial  action there will be a greenbelt in this area
 to camouflage  the site from view of the motorists along Marshall
 Road.  This greenbelt will be enhanced with vegetation consisting
 of grass and fast-growing  native trees which will nearly
 eliminate  any  contaminants from becoming airborne for  contact
 with the passerby.   When the site is remediated to 5 ppb the
 average  concentration of dioxin in the area along Marshall Road
 will be  less than 1 ppb.   This is due to the fact that after
 grids where dioxin  concentrations exceeding 5 ppb are  excavated

                                48

-------
 and replaced with clean backfill material,  data indicate that
 average dioxin concentrations  along Marshall  Road will  be at or
 below 1 ppb because some portions of that area  currently have
 dioxin concentrations  less  than  1 ppb.   The process  of  averaging
 resulting  dioxin concentrations  results  in  a  less than  1 ppb
 average.

      Extremely conservative assumptions  were  made to calculate
 the risk for a casual  passerby.   Using the  most conservative
 assumptions possible,  the risk posed by  the site after
 remediation was within EPA's acceptable  risk  range.  Therefore,
 the site cleanup to 5  ppb provides  for a fully  protective  remedy.
 See memorandum from Ghassan Khoury  to Philip  Allen in the
 Administrative Record.

 Current  Unprotected Worker

     The current  unprotected worker was  assumed  to be exposed to
 substances  of  potential concern through  the same exposure  routes
 as  the trespasser:   Incidental ingestion of soil, dermal
 absorption  of  soil,  dermal  absorption from surface water,  and
 inhalation  of  airborne soil and vapors.  The  on-site worker could
 also potentially  come  into  contact with  all on-site surface
waters, including outfalls,  on a regular basis.   Contact could
occur during performance of general maintenance  activities.
However, because  ground water has no current on-site uses, the
 current worker has  limited potential for contact with ground
water.  Thus, the ground water pathway was not evaluated.

Future Unprotected worker

     The future unprotected worker was assumed to be exposed to
the substa-oes of potential concern through the  same exposure
routes as the current unprotected worker, with the addition of
the ingestion of  site ground water.  Ground water is currently
not used as a drinking water source for the site, and it is
unlikely that  it  will be used as such in the  future because of
 the availability  of  public  water.  Conservatively, this pathway
was evaluated, but  EPA did  not include this exposure route in
 developing  remediation goals for the  site.

     A summary of the  exposure pathways  used  for quantitative
 evaluation  is  shown in Figure  10.   Models used  to calculate
 intakes, i.e..  doses of the substances of concern for each
 receptor through the various exposure routes  are shown  in Tables
 6,  7, 8, 9,  10,  and 11.

 6.3.3  Toxicity Assessment

     The toxic effects of a chemical generally  depend upon the
 level of exposure (dose), the  route of exposure (oral,
 inhalation,  dermal), and the duration of exposure (acute,

                                49

-------
    SOURCE
           RELEASE
          MECHANISM
                                SOURCE
                     RELEASE
                    MECHANISM
                                                            SOURCE
POTENTIAL
EXPOSURE
  ROUTE
                                                                                                  RECEPTOR
D



SOIL

DUST GENERATION
VOLATILIZATION _
	 • 	

•••IB—
AIR

AIR
.1 	

. 	 	 	 •!






	 	 	 . 	 • 	
VOLATILIZATION _
RUNOFF
RUNOFF^ 	



DRAINAGE
HITCHES

I

DISCHARGE




AIR
~\








1
.1
1




— A

VOLATILIZATION |~~"
f
	 M
. . .«
c
/ CACHING
	 • 	 '

— — ™
R°rRy^sB<


1
— 	 ~ DISCHARGE
MB/\I ikinui ATER
QHwUNl/wf A I en
_— 	 	 	 ' 	


DISCHARGE
....• DisCHARGE

» AIR




••
WATER
5OLLECTK
SYSTEM'
	 1
ns*Antnr 	 . Dathuiau 1





—
)N



:




\
J 	 *
L_
INHALATION
INHALATION i

INQESTKDN f
DERMAL
CONTACT
INHALATION
INGESTION [
DERMAL 1
CONTACT 1
INHALATION |
INQES: ION
DERMAL
CONT^'JT

DERK XL
CON"1 «^T
VAP^I
1 INHALATION
IKJ/'ICCTI/'MU
IINUCO I KJN
DERMAL
CONTACT
                                                                                     H
LEGEND:
 X
• tXpUSUI* p»Mi"-7 --
I cannot be completed

U Exposure route is highly unlikely

  NOTES: '-
                                                     '»•  uncertain
                                                                                          r
                                                                                     JL
1 x

1 x

1 x

1 o

1 u

1 u

1 o

\ u

\ x

1 '

\ '

] '
II

II

II

II

II

II

II

II

II

II

II

II
x

x

x

o

u

X

o

u

X

s

1

1
1 x

1 x

1 x

1 o

1 u

II x

II o

II u

II x

II s

II o

II x
                                                                                                   HERCVERM-l/X.OAHOMBDMVCvRSKQRP
                                        CONCEPTUAL MODEL OF POTENTIAL EXPOSURE ROUTES

-------
                     Model for Calculating Doses through the
                           Incidental Ingestion of Soil
                    Soil Ingestion Dose      CS * SIR * EF * ED
                       (mg/kg-day)     =       BW AT
 Where:
 CS   = Chemical concentration in surface soil (mg/kg)
 CTr*  -• Soil ingestion rat*1 (kg/day)
 EF   = Exposure frequency (days/year)
 ED   = Exposure duration (years)
 BW  = Body weight (kg)
 AT  = Averaging time (days)
Exposure Assumptions
All Scenarios:
CS  = Surface soil exposure concentrations
Trespasser:
SIR  = 5.0E-05 kg/day (U.S. EPA, 1994a)
EF  = 1 day/week, 26 weeks/year
ED  = 5 years
BW  = 56 kg, average weight of a 12-to 18-year old (U.S. EPA, 1989a)
AT  = 365 days/year x 5 years (for evaluating noncancer risk)
     = 365 days/year x 70 years (for evaluating cancer risk)
Worker (Current and Future):
SIR  =  5.0E-05 kg/day (U.S. EPA, 1991)
EF  =  250 days/year (U.S. EPA, 1991)
ED  =  25 years (U.S. EPA, 1991)
BW =  70 kg (U.S. EPA, 1991)
AT  =  365 days/year x 25 years (for evaluating noncancer risk)
     =  365 days/year x 70 years (for evaluating cancer risk)
                               TABLE  6

-------
                       Model for Calculating Doses through
                          Dermal Absorption from Soil
   Soil Dermal Absorption Dose    CS * SA * AF ' ABS (or RABS1 * EF * ED
           (mg/kg-day)          =                 BW AT
 Where:
 CS     = Chemical concentration in surface soil (rag/kg)
 SA     = Skin surface area available for contact (cm2/day)
 AF     = Sr»il-to-skin adherence factor (kg/err2)
 ABS    = Absorption factor (unitless)
 RABS  = Relative dermal absorption factor (unitless)
 EF     = Exposure frequency (days/year)
 ED     =  Exposure duration (years)
 BW     =  Body weight (kg)
AT    =  Averaging time (days)
Exposure Assumptions
All Sec	nos:
CS    = Surface soil exposure concentrations
AF    = l.OOE-06 kg/cm2, reasonable upper limit of soil adherence factor (U.S.
         EPA, 1992a)
ABS   = 0.03 for dioxin (U.S. EPA, 1992a)
RABS = 0.50 for all chemicals except dioxin, based on guidance in U.S. EPA, 1989c
Trespasser.
SA    = 1,950 cm2/day, based on the average arm and hand surface area of a 12- to
         18-year old (U.S. EPA, 1989a)
EF    =1 day/week, 26 weeks/year
ED    = 5 years
BW   = 56 kg, average weight of a 12- to 18-year old (EPA, 1989a)
AT    = 365 days/year x 5 years (for evaluating noncancer risk)
       = 365 days/year x 70 years (for evaluating cancer risk)
                               TABLE  7

-------
                       Model for Calculating Doses through
                          Dermal Absorption from Soil
                                  (continued)
 Worker (Current and Future):

 SA    = 2,000 cm2/day, based on the average arm and hand surface area of adult
          males (U.S. EPA, 1989a)

 EF    = 250 days/year (U.S. EPA, 1991)

 ED    =25 years (U.S. EPA, 1991)

 BW    =  70 kg (U.S. EPA, 1991)

AT    =  365 days/year x 25 years (for evaluating noncancer risk)
       =  365 days/year x 70 years (for evaluating cancer risk)
                               TABLE 7 (cent)

-------
                     Model for Calculating Doses through the
                            Inhalation of Airborne Soil
               Soil Inhalation Dose      CS * RD * IV ' EF * ED
                   (mg/kg-day)       =          BW * AT
 Where:
 CS    = Chemical concentration in surface soil (mg/kg)
 RD   = Respirable-size soil particle concentration in air (i.e., PM10) (kg/m3)
 IV    = Inhalation volume (m3/day)
 EF    = Exposure frequency (days/year)
 ED    = Exposure duration (years)
 BW   = Body weight (kg)
 AT    = Averaging time (days)
 Exposure Assumptions
All Scenarios:
 CS   = Surface soil exposure concentrations
 RD   = 3.1E-C8 kg/m3 (URS, 1990)
Trespasser.
 IV    = 2.5 m3/day,  based on 1 hour of moderate activity on the site (U.S. EPA,
         1989a)
 EF    = 1 day/week, 26 weeks/year
 ED    = 5 years
 BW   = 56 kg, average weight of a 12- to 18-year old (U.S. EPA, 1989a)
 AT    = 365 days/year x 5 years (for evaluating noncancer risk)
       = 365 days/year x 70 years (for evaluating cancer risk)
                                  TABLE 8

-------
                     Model for Calculating Doses through the
                           Inhalation of Airborne Soil
                                  (continued)
 Worker (Current and Future):

 IV    =20 m3/day (U.S. EPA, 1991)

 EF    =  250 days/year (U.S. EPA, 1991)

 ED    =  25 years (U.S. EPA,  1991)

BW    =  70 kg (U.S. EPA, 1991)

AT   =  365 days/year x 25 years (for evaluating noncancer risk)
      =  365 days/year x 70 years (for evaluating cancer risk)
                              TABLE  8  (cent)

-------
                     Model for Calculating Doses through the
                             Inhalation of Vapors
                 Vapor Inhalation Dose     CA * IV * EF * ED
                     (mg/kg-day)       =       B W* AT
 Where:
 CA  = Chemical vapor concentration in air (mg/m3)
 TV   = Inhalation volume (m3/day)
 EF   = Exposure Frequency (days/year)
 ED   - Exposure duration (years)
 BW  = Body weight (kg)
 Af   = Averaging time (days)
Exposure Assumptions
All Scenarios:
CA  = Vapor concentrations
Trespasser
IV  = 2.5 m3/day, based on 1 hour of moderate activity on the site (U.S. EPA,
       1989a)
EF  = 1 day/week, 26 weeks/year
ED  = 5 years
BW  = 56 kg, average weight of a 12- to 18-year old (U.S. EPA, 1989a)
AT  = 365 days/year x 5 years (for evaluating noncancer risk)
     = 365 days/year x 70 years (for evaluating cancer risk)
Worker (Current and Future):
IV  = 20 m3/day (U.S. EPA, 1991)
EF  =  250 days/year (U.S. EPA, 1991)
ED  =  25 years (U.S. EPA, 1991)
BW =  70 kg (U.S. EPA, 1991)
AT  =  365 days/year x 25 years (for evaluating noncancer risk)
     =  365 days/year x 70 years (for evaluating cancer risk)           	
                              TABLE 9

-------
                      Model for Calculating Doses through
                     Dermal Absorption from Surface Water
    Surface Water
 Dermal Absorption Dose  =   CSW * CF-1 * SA * PC * ET ' CF-2 * EF * ED
    (mg/kg-day)                            BW • AT
 Where:
 CSW  =  Chemical concentration in surface water (mg/L)
 CF-1  =  Conversion factor (mg//^g)
 SA    =  Skin surface ar^a available for con*r ~t (cm2)
 PC    =  Dermal permeability coefficient (cm/hour)
 ET    =  Exposure time (hours/day)
 CF-2   =   Conversion factor (L/cm3)
 EF    =   Exposure frequency (days/year)
 ED    =   Exposure duration (years)
 BW    =  Body weight (kg)
AT    =  Averaging time (days)                                      	
Exposure Assumptions
All Scenarios:
CF-1  =  Img/l.OOO/ig
PC    =  Permeability coefficient.
CF-2  =  lL/l,OOOcm3
Trespasser:
CSW  =  Surface water exposure concentrations for Rocky Branch Creek, presented
         in Table 3-2
SA   =  1,970 cm2, average hand and foot surface area of a 12- to 18-year old (U.S.
         EPA, 1989a)
ET   =  1 hour/day
EF   =  1 day/week, 13 weeks/year
ED   =  5 years
BW  =  56 kg, average weight of a 12- to 18-year old (U.S. EPA, 1989a)
AT   = 365 days/year x 5 years (for evaluating noncancer risk)
      = 365 days/year x 70 years (for evaluating cancer risk)
                              TABLE  10

-------
                      Model for Calculating Doses through
                     Dermal Absorption from Surface Water
                                  (continued)
 Worker (Current and Future):
 CSW  =  Surface water exposure concentrations based on all surface waters,
          presented in Table 3-2
 SA    =840 cm2, average hand surface area of an adult (U.S. EPA, 1989a)
 ET    =1 hour/day
 EF    =  1 day/week, 50 weeks/year (U.S FPA, 19°^
 ED    = 25 years (U.S. EPA, 1991)
 BW    = 70 kg (U.S. EPA, 1991)
AT    = 365 days/year x 25 years (for evaluating noncancer risk)
 	=  365 days/year x 70 years (for evaluating cancer risk)
                                TABLE 10 (cont)

-------
                     Model for Calculating Doses through the
                           Ingestion of Groundwater
             G-oundwater Ingestion Dose    CGW * GIR * EF * ED
                   (mg/kg-day)         =        BW * AT
 Where:
 CGW =  Chemical concentration in groundwater (mg/L)
 C "c   =  Groundwater ingestion rate (L/day)
 EF    =  Exposure frequency (days/year)
 ED    =  Exposure duration (years)
 BW    =  Body weight (kg)
 AT    =  Averaging time (days)
Exposure Assumptions
Worker (Future):
CW   =   Groundwater exposure concentrations
IR    =   1 L/day (U.S. EPA, 1991)
EF   =   250 days/year (U.S. EPA, 199n
ED   =   25 years (U.S. EPA, 1991)
BW   =   70 kg (U.S. EPA, 1991)
AT   =   365 days/year x 25 years (for evaluating noncancer risk)
      =   365 days/year x 70 years (for evaluating cancer risk)
                                TABLE 11

-------
chronic,  subchronic,  or  lifetime).  Thus, a  full description of
the toxic effects  of  a chemical  includes a listing of what
adverse health  effects the  chemical may cause  (carcinogenic and
noncarcinogenic),  and how the  occurrence of  these effects depends
upon dose, route,  and duration of exposure.

     Slope factors (SF's) have been developed  by EPA for
estimating excess  lifetime  cancer risks associated with exposure
to potentially  carcinogenic contaminants of  concern.  SF's, which
are expressed in units of (mg/kg-day)'1, are multiplied by the
estimated intake of potential  carcinogen, in mg/kg-day, to
provide an upper-bound estimate  of the e^^ess  lifetime cancer
risk associated with  exposure  at that intake level.  The term
"upper bound" reflects the  conservative estimate of the risks
calculated from the SF.  Use of  this approach makes
underestimation of the actual  cancer risk unlikely.  Slope
factors are derived from the results of human epidemiological
studies or chronic animal bioassays *-o which animal-to-human
extrapolation and uncertainty  factors have been applied.

     References doses (RfD's)  have been developed by EPA for
indicating the potential for adverse health effects from exposure
to contaminants of concern exhibiting non-carcinogenic adverse
health effects.   RfD's which are expressed in units of mg/kg-day,
are estimates of daily (maximum)  exposure levels for the human
population, including sensitive  subpopulations.  Estimated
intakes of contaminants of concern from environmental media
(e.g..  the amount of chemical ingested from drinking contaminated
ground water)  can be compared to the RfD.   RfD's are derived from
human epidemiological studies or animal studies to which
uncertainty factors have been applied to account for the use of
animal data to predict effects on humans.

     loxicity information used to calculate the risk for
carcinogenic risk including the  slope factor, the weight of
evidence, and source of the toxicity information can be found in
Tables 12 and 13.  Chronic and subchronic references doses used
in the toxicity assessment can be found in Tables 14 and 15.

     In numerous public forums over the past year, EPA has
summarized the  preliminary results from the  dioxin reassessment
study in  order  to  accept public  comment during the scientific
peer review process.  One of the major conclusions was that the
"weight-of-evidence"  suggested that dioxin,  furans, and dioxin
like compounds  are likely to present a cancer  hazard to humans,
and that  a risk specific dose  of dioxin at 0.01 pico grams  (pg)
TEQ per kilogram  (kg) of body  weight per day,  resulted  in one
additional cancer  in  one million.  This risk specific dose
estimate  represents a plausible  upper  bound  on risk based on the
evaluation of both animal and  human data.  With regards to
average intake, humans are  currently exposed to background  levels


                                 60

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                   U.S. EPA and IARC Categorizations of the Carcinogenic
                                Substances of Potential Concern
Substance
Organics
Chloroform
Methylene chloride
2,3,7,8-TCDD
2,4,6-Trichlorophenol
EPA
Carcinogenirity
Category*'1'
IARC
Carcinogenicity
Category0-"

B2
C
B2
B2
2B
2B
2B
NC
Inorganics
Arsenic
Lead
A
B2
1
2B
•References: IRIS, 1995; U.S. EPA, 1994b
"Category definitions (U.S. EPA, 1986b):
    A   =  Human carcinogen (sufficient evidence from epidemiologic studies).
    62   =  Probable human carcinogen (sufficient evidence from animal studies and inadequate or no human
           dataV
    C   =  Pos&iole human carcinogen (limited evidence from animal studies and no iiuman data)
'Reference: WHO, 1987
"Category definition (WHO, 1987):
    1    =  Human carcinogen (sufficient evidence of carcinogenicity in humans).
    2B   =  Possible  human carcinogen (limited evidence  of carcinogenicity in humans in the absence of
           sufficient evidence of carcinogenicity in experimental animalyt inadequate evidence of carcinogenicity
           in humans or no human data and sufficient evidence  of carcinogenicity in experimental animals; or
           inadequate evidence of carcinogenicity or no data in humans and limited evidence of carcinogenicity
           in experimental animals with supporting evidence from other relevant data).

NC = Not categorized.
                                          TABLE  12

-------
                                      Cancer Slope Factors
Substance
Organic*
Chloroform
Methylens chloride
23,7,»-TCDD
2,4,6-
Trichlorophenol
Inhalation
Slope Factor
(mg/kg-day)-1

NC
NC
L5E+05
9.7E+03
1.1E-02"
Reference
or Basis

—
—
VS. EPA,
1994b
OSF
IRIS, 1995
Oral Slope
Factor
(mg/kg-day)-1
Reference
or Basis

6.1E-03
7J5E-03
UE+05
9.7i- M)3
1.1E-02
IRIS, 1995
IRIS, 1995
U.S. EPA,
1994b
ChemRisk,
1990
IRIS, 1995
Dermal Slope
Factor*
(mg/kg-day)-1

NC
NC
3.0E+05
1.9E+04
2.2E-02
Inorganics
Arsenic
Lead
NC
NC
—
—
USE+OO"
NTV
IRIS, 1995
-
NC
NC
'Dermal slope factors were derived from the oral slope factors as described in Subsection 3323.
"Derived from a unit risk, assuming the inhalation of 20 m3 of air per day and a body weight of 70 kg (U.S. EPA,
 1994b).
""Derived from a unit risk, assuming the consumption of 2 liters of water per day and a body weight of 70 kg
 (U.S. EPA, 1994b).

NC = S bstance is not of concern through this exposure route.
NTV =  A toxitity value was not available.
OSF = Oral slope factor was used (Subsection 33.2.2).
                                         TABLE 13

-------
                                                Chronic Reference Doses (RfDs)
w
I—'
p-
Organic*
Acetone
.,
Chloroform
              "•
2-Chlorophenol
4-Chlorophenol
^M*^™"!"™"^"1^^^"*^™l—*^^
2,4-D
—..           ""
2,6-D
^••^«-^-»-
 2,4-Oichlorophenyl
 2.6-Dichlorophenyl
     —^^^—^•~"1
 Methylene chloride
_»————
 Phtnol
 •ii    —
 Silver
 •n    ••
 2,4,5-T^
 ^—•-    -
 2,4,6-T
 2,3,7,8-TCDD
 Tetrachlorobenzene
 .             ^~~~~"
 Toluene
         •
  2.3.6-Trichlorophenol_
Reference
or Basis
OralRfD
(mg,'kg-day)
Reference
or Basis
                                                                                                                    Dermal RfD*
                                                                                                                    (mg/kg-day)
NC
„ 	 —
NC
_— 	 	 	
5.0E-03
— , 	 	 	
NC
— . 	 • 	
l.OE-02
. 	 • — • —
NC
3.0E-03
__ 	 . — . 	 	
3.0E-03
_ 	 1 	 • 	
NC
	 	
NC
___ 	 • 	 • 	
8.0E-03
. 	 	 	 	 	
l.OE-02
— 	 • 	 • 	
NC
__ 	 	
NTV
. — . 	 	 	
3.00E-04"
— . 	 • 	
NC
NC
—
—
ORD
—
ORD
—
ORD
ORD

—
ORD
ORD


ORD

—
l.OE-01
l.OE-02
5.0E-03
5.0E-03
l.OE-02
l.OE-02
3.0E-03
3.0E-03
6.0E-02
6.0E-01
8.0E-03
l.OE-02
l.OE-02
NTV
3.0E-04C
2.0E-01
l.OE-01
IRIS, 1995
IRIS, 1995
IRIS, 1995
Isosncr
IRIS, 1995
Isomer
IRIS, 1995
Isomer
IRIS, 1995
IRIS, 1995
IRIS, 1995
IRIS, 1995
Isomer
• —
IRIS, 1995
IRIS, 1995
Isomer
NC
NC
4.5E-03 (dw)
4.5E-03 (dw)
5.0E-03 (d)
5.0F-03(d)
2.7E-03 (dw)
2.7E-03 (dw)
NC
5.4E-01 (g)
4.0E-03 (d)
5.0E-03 (d)
5.0E-03(d) |
NTV 1
NC 1
1.8E-01 (g) 1
5.0E-02 (d) 1

-------
                                                    Chronic Reference Doses (RfDs)
                                                                (continued)
r1
w
o
o
0
          Substance
Oryanics (continued)
2.4,5-Trichlorophenol
2,4,6-Trichlorophenol
Inorganics	
Antimony	
Arsenic
Chromium
Copper
Lead
Mercury
Nickel
Silver   	
Thallium
 Zinc
•Chronic dermal RfDs were
in the studies on which the
    d    =  diet
    dw   =  drinking water
lation RfD
5/kg-day)
L.OE-01
L.OE-01
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
Reference
or Basis

ORD
ORD
Oral RfD
(mg/kg-day)

l.OE-01
l.OE-01
Reference
or Basis

IRIS, 1995
Isomer
Dermal RfD'
'mg/kg-day)

5.0E-02 (d)
5.0E-02 (d)

—
—
—
—
—
—
—
—
—
—
4.0E-04
3.0E-04
5.0E-03"
3.7E-02'
NTV
3.0E-04
2.0E-02
5.0E-03
NTV
3.0E-01
IRIS, 1995
IRIS, 1995
IRIS, 1995
U.S. EPA, 1994b
—
U.S. EPA, 1994b
IRIS, 1995
IRIS, 1995
—
IRIS, 1995
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
                                                chronic oral RfDs as described in Subsection 3.3.3.3.  The route by which the chemical was administered
                                                 is indicated in parentheses as follows:
                                           bot

-------
                                                Subchronic Reference Doses (RfDs)
r1
M
                                     Inhalation RfD

                                      (mg/kg-day)
Reference
or Basis
Oral RfD
(mg/kg-day)
Reference
or Basis
Dermal RfD*
(mg/kg-day)
                                                                                NC
                                                                                NC
                                                                              5.0E-02
                                                                            5.0E-02(D)
                                                                              l.OE-02
                                                                              l.OE-02
3.0E-03
                                                                              3.0E-03
                                                                                NC
                                                                             6.0E-01(D)
                                                                              8.0E-03
                                                                               l.OE-01
                                                                               l.OE-01
                                                                                NTV
                                                                                NC
                                                                             2.0E + 00(D)
                                                                               l.OE + 00
              U.S. EPA, 1994b
                   Isomer
               U.S. EPA, 1994b
                   Isomer
' I.S. EPA, 1994b
                   Isomer
               U.S. EPA, 1994b
               U.S. EPA, 1994b
               U.S. EPA, 1994b
                   Isomer
               U.S. EPA, 1994b
                    Isomer
                                        NC
                                        NC
                     4.5E-02 (dw)
                     4.5E-02 (dw)
                      5.0E-03 (d)
                      5.0E-03(d)
2.7E-03 (dw)
                     2.7E-03 (dw)
                                        NC
                      5.4E-01 (g)
                      4.0E-03 (d)
                       5.0E-02 (d)
                       5.0E-02(d)
                                        NTV
                                         NC
                       1.8E + 00 (g)
                       5.0E-01(d)

-------
                                                      Subchronic Reference Doses (RfDs)
                                                                  (continued)
r4
w
n
o
                  Substance
          d
          dw
          g
        (D)

        NC
        NTV
        ORD
                                         Inhalation RfD
                                          (mg/kg-day)
Reference
or Basis
Oral RfD Reference
(mg/kg-day) or Basis
Dermal RfD*
(mg/kg-day)

ORD
ORD
l.OE+00
l.OE+00
U.S. EPA, 1994b
Isomer
5.0E-01 (d)
5.0E-01 (d)
                                    calculated from the subchronic oral RfDs as described in Subsection 3.3.3.3. The route by which the chemical
                                    which the oral RfD was based is indicated in parentheses as follows:
                                                                                                                                       was
               =   diet
               =   drinking water
               =   gavage
TheTubstance is not of concern for the trespasser scenano throug- the oral route.
TteS«l RfD was used only to calculate the dermal RfD.
The chemical is not a substance of potential concern through this exposure route.
A toxicity value was not available.
The subchronic oral RfD was used.

-------
 of  dioxin-like compounds on the order of  3-6  TEQ's  pg/kg/day.
 Therefore,  plausible upper-bound risk estimates  for general
 population  exposures to dioxin and related compounds (at
 background  levels)  may be as high as  1 in 10,000 (1X10"*) to  1 in
 1,000  (1X10"3) .  High end estimates of  body burden of individuals
 in  the general population (approximately  the  top 10% of the
 general population)  may be greater than 3 times  higher.

     What should  also be noted here is that the  risk calculations
 presented in  the  baseline risk assessment (and reported in this
 summary) for  dioxin are based on exposure to  2,3,7,8-TCDD only.
 Additional  sampling performed by +. ve PRP  at the  request of EPA
 shows  that  other  dioxin and furan compounds are  present at the
 site,  and could contribute to approximately 20 percent greater
 risk than TCDD alone,  i.e..  the risk estimates presented could be
 adjusted upward by  20  percent.

     It is  also important to note that the  non-cancer risks
 outlined in the baseline risk assessment  and  summarized here do
 not address the non-cancer risks  associated with low level
 exposures to dioxin.   As  a result, the  baseline risk assessment
may underestimate the  non-cancer  risk  associated with exposure to
 site contaminants.  The  reason being is that  a reference dose
 (RfD)  (the daily  intake  of  a  chemical to which an individual can
be exposed without experiencing non-cancer health effects)  has
not been established by EPA  for dioxin at this time.  If a
reference dose were to be  calculated for dioxin based on human
and animal data,  it could  result  in an acceptable intake level
 for humans below the current  level of daily intake in the general
population.   EPA's dioxin  reassessment study has suggested that
at some dose, and possibly within one order of magnitude of
average background body burdens, dioxin exposure can result in
noncancer health effects  in humans.  These  effects include
developmental and reproductive effects, immune suppression, and
disruption  of regulatory hormones.

 6.3.4  Risk Characterisation

 Cancer Risk

     The risk  of  getting cancer from exposure to a  chemical  is
 described in terms  of  probability that an individual exposed for
 his or her  entire lifetime will develop cancer by the age 70.
 For carcinogens,  risks are estimated as the incremental
 probability of an individual developing cancer over a life-time
 as a result of exposure to the carcinogen.  Excess  life-time
 cancer  risk is calculated using the following equation:
                                67

-------
         Cancer        Lifetime              Cancer
         Risk     =     Averaged        x     Slope
                      Dose                  Factor
                       (mg/kg-day)           (mg/kg-day)'1

     These risks are probabilities  that  are generally expressed
in scientific notation  (e.g. , 1  x 10"6  or IE"6) .  An excess
lifetime cancer  risk of  1 x  10"45  indicates that, as a  reasonable
maximum  estimate, and individual has  a 1 in 1,000,000 chance of
developing cancer as a result of site  related  exposure to  a
carcinogen over  a 70-year lifetime  under the specific exposure
conditions at a  site.

     Tables 16,  17, and  18 summarize the potential lifetime
cancer risk for  the three exposure  scenarios examined in the risk
assessment.

     The  calculated excess lifetime cancer  risk for the
trespasser scenario was  8X10'5 or approximately 8  in 100,000.  The
exposure  routes  that posed the majority of  the risk to the
trespasser were  through  dermal absorption from surface water,
incidental soil  ingestion, and dermal  contact with soil.   TCDD
dioxin was the only contaminant  that contributed  to an excess
cancer risk greater that 1X10"6.

     The  calculated excess lifetime cancer  risk for the current
unprotected worker scenario based on all exposure routes was
approximately l  in 1,000 or 1X10'3.   This risk exceeds  EPA's
acceptable risk range.   The exposure routes that  posed the
majority  of the risk to  the current unprotected worker were
through dermal contact with soil (6X10"*), dermal  contact with
surface waters (5X10"*),  and incidental soil  ingestion  (2X10"*) .

     T^  calculated excess lifetime cancer  risk for the future
unprotected worker scenario based on all exposure routes was
approximately 5  in 100 or 5X10'2.  This risk exceeds EPA's
acceptable risk  range.   The exposure routes that  posed the
majority  of the  risk to  the future  unprotected worker were
through soil ingestion  (2X10"*) ,  dermal contact with soil (6X10"*) ,
dermal contact with surface water (5X10"*),  and ground water
ingestion (5X10'2) .

     Over 99 percent of  the  calculated risk for all  exposure
scenarios was contributed by  2,3,7,8-TCDD.   As mentioned earlier,
when all dioxin  and furan congeners are  factored  into the  risk
estimates, those estimates may  be 20  percent higher.

Non—cancer Risk

     The potential for  non-carcinogenic  effects is evaluated by
comparing an exposure  level  over a  specified time period  (e.g.,,


                                 68

-------
                                                          OTEMTIAL LIFETIME CANCER RISK
                                                                TRESPASSER
-3
>
33

71
SUBSTANCE
2^8-TCb& (U.S. EPA)
(Ch«mRI«h)
2,4,6-Trlchloroph»nol
TOTAL (U.S. EPA)
TOTAL (Ch»mRi8kl
SOIL
INGESTION
4.05E-07
1.70E-10
6.27E-06
4.06E-07
DERMAL
ABSORPTION
FROM SOIL
9.29E-07
3.31E-09
1.47E-05
9.32E-07
SOIL
INHALATION
6.28E-10
2.63E-13
9.72E-09
6.29E-10




VAPOR
INHALATION
1.94E-10
1.26E-11
2.50E-14
1.94E-10
1.26E-H
DERMAL |
ABSORPTION
FROM SURFACE
WATER
4.05E-06
4.41E-10
6.39E-05
4.05E 06
TOTAL
8.48E-05
5.38E-06
3.92E-09


TOTAL LIFETIME
CANCEF RlŁ (U.S EPA) 8.49E-05
TOTAL LIFETIME
CANCER RISK (CtwmRltk) 5 39E-06

-------
POTENTIAL LIFETIME CANCER RISK
CURRENT UNPROTECTED WORKER




H
r>
B
f
w

SUBSTANCE
_. — =
2,3.7.8-TCDD (U.S. EPA)
//•'fc.mmQlakl
^Cn9ninl«A;
2,4,6-Trlchloroph«nol
TOTAL (U.S. EPA)
rnTAL (Ch«mRI«Kl 	 _
	 i •» -^-^— ^•"^'•^
SOIL
INGESTION
..
2.41E-04
1.56E-05
6.53E-09
2.41 E-04
V56E-05
DERMAL
ABSORPTION
FROM SOIL
5.79E-04
3.67E-05
1.31E-07
5.79E-04
3.68E-0C

1 — '
-J
SOIL
INHALATION
2.99E-06
1.93E-07
8.10E-11
2.99E-06
1.93E-07


VAPOR
INHALATION
5.98E-08
3.86E-09
7.69E-12
5.98E-08
3.87E-09
DERMAL
ABSORPTION
FROM SURFACE
WATER
4.68E-04
2.97E-05
1.14E-06
4.70E-04
3.08E-05
TOTAL
1.29E-03
8.21E-05
1.28E-06


TOTAL LIFETIME
CANCEP RISK (U.S. EPA) 1.29E-03
TOTAL LIFE! ^E
CANCER RISK (CtomFUtk) B.34E-05

-------
                                                                     POTENTIAL LIFETIME CANCER RISK
                                                                     FUTURE UNPROTECTED WORKER
H
Ł
t-<
w
00
                         SUBSTANCE
Chloroform
Methytone eWorld*
2,3.7,8-TCDD (U.S. EPA)
       (Ch*mRlsk)
2.4.6-Trichloroph*nol


Arsenic
Lead

   TOTAL (U.S. EPA)
                                              SOIL
                                            INGESTION
 NA
 NA
2.41E-04
1.56E-05
6.53E-09


 NA
 NA

2.41E-04
ERMAL
ORPTION
3M SOIL
NA
NA
5.79E-04
3.67E-05
1.31E-07
NA
NA
5.79E-04
3.68E-05
SOIL
INHALATION
NA
NA
2.99E-06
1.93E-07
8.10E-11
NA
NA
2.99E-06
1.93E-07
VAPOR
INHALATION
NA
NA
598E-08
3.86E-09
7.69E-12
NA
NA
5.98E-08
3.87E-09


DERMAL
ABSORPTION
FROM SURFACE
WATER
NA
NA
4.68E-04
2.97E-05
1.14E-06
NA
N'
4.70E-04
3.08E-05
GROUNDWATER
INGESTION
1.51E-07
3.41E-07
5. QBE -02
3.29E-03
3.81E-04
3.42E-05
N1V
5.13E-02
3.70E-03
TOTAL
1.51E-07
3.41E-07
5.21E-02
3.37E-03
3.82E-04
3.42E-05
NTV


TOTAL LIFETIME
CANCER RISK (U.S. EPA) 5.26E-02
TOTAL LIFETIME
CANCER RISK (ChemRlsk) 3. 79E - 03
                                           NA - Not applicable. Ch*mlcal is not of concern through this exposure rout*.
                                           NTV~- Not calculated because a slope factor was not available.

-------
 life-time) with  a reference dose derived  for a similar exposure
 period.  The ratio of exposure to toxicity  is called the hazard
 quotient.  By  adding the hazard quotients for all contaminants of
 concern which  affect the same target organ  (e.g.. the liver)
 within a medium  or across all media to which a population may
 reasonably be  exposed, the Hazard Index (HI) can be generated.
 In general, a  total hazard index of 1 is  used as a benchmark of
 potential concern for non-cancer health effects.

         Hazard         Daily          Reference
         Quotient   =    Intake    -5-    Dose

 Tables 19, 20, and 21 summarize the hazard quotients and indices
 calculated for the same potentially exposed individuals.

     The total hazard index calculated for contaminants of
 concern other than dioxin for a trespasser was approximately 0.4,
 based on soil ingestion, soil inhalation,  dermal contact with
 soil, and dermal contact with surface water.  Again, the
 benchmark of concern for non-cancer health effects is 1.  A total
 hazard index of approximately 4 was calculated for the current
 unprotected worker with dermal contact with 2,4-D contributing
most of the risk.  For the future unprotected worker a hazard
 index of 5,520 was calculated.  The ground water ingestion
pathway contributed most to the non-cancer risk for the future
unprotected worker.   Again,  for this ROD EPA did not consider the
ground water ingestion exposure route in developing thfi
remediation goals for this site,  because drinking water for the
Jacksonville area is provided from sources near Little Rock, and
 it is doubtful that any wells on this property will ever be used
 for domestic purposes.

 6.3.5  Uncertainty Analysis

     Within the Superfund process,  baseline risk assessments are
developed to provide risk managers a numerical representation of
 the se/erity of contamination present at a site, as well as to
provide an indication of the potential for adverse public health
 effects.  There are many inherent and imposed uncertainties in
 the risk assessment process.  Some of these uncertainties may
 lend in the under estimation of site risk others in its
 overestimation.

     Factors that Tend to Underestimate Exposure/Risk

 •    Lack of RfD's or SF's for all chemicals of  concern;

 •    Nonquantification of some exposure pathways;

 •    Exclusion of chemicals present but not detected;
                                72

-------
                                                                      HAZARD QUOTIENTS AND INDICES
                                                                             TRESPASSER
W
Ł
                                  SUBSTANCE
*-v-..ioroph«nc
4-ChlofOph«nol
2.4-D
2.8-D
2.4-Dichlofoph«nol
2,6-Dichloroph«nol
Phenol
Silvex
2,4.5-T
2.4,6-T
2,3.7.8-TCDD
Tetrachlorobenzant
Toluene
2,3.6-Trlchloropheiol
2'4 5_Trlchlorophenol
2'.4,6-Trlchlorophenol

SOIL
GESTION

4.96E-07
NA
1.97E-02
NA
1.06E-04
1.40E-05
NA
8.75E-04
1.59E-04
NA
NTV
NA
NA
NA
.91E-07
2.16E-07
209E-02


DERMAL
ABSORPTION
FROM SOIL
9.67E-06
NA
3.84E-01
NA
2.07E-03
2.73E-04
NA
1.71E-02
3.10E-03
NA
NTV
NA
NA
NA
3.72E-06
4.22E-06
4.07E-01
SOIL
INHALATION

7.69E-10
NA
3.06E-05
NA
1.64E-07
2.17E-08
NA
1.36E-06
2.46E-07
NA
NTV
NA
NA
NA
2.96E-10
3.35E-10
3.23E-05

VAPOR
INHALATION

1.34E-10
NA
NC
NA
3.60E-08
6.04E-09
NA
5.96E-09
3.18E-09
NA
NTV
NA
NA
NA
5.09E-10
3.18E-11
5.19E-08
DERMAL
ABSORPTION
FROM SURFACE
WATER
2.02 E'- 06
1.80E-05
2.75E-04
8.6BE-05
3.62E-04
2.22E-05
4.38E-08
9.96E-05
2.76E-05
< 55E-05
NTV
NA
5.01E-07
2.85E-07
1.58E-06
5.62E-07
9.10E-04
==ir_.. .
HAZARD INDEX
(BY
SUBSTANCE)
1.22E-05
1.60E-05
4.04E-01
8.68E-05
2.54E-03
3.09E-04
4.38E-08
1.80E-02
3.29E-03
1.55E-05
NTV
NA
5.01 E- 07
2.85E-07
5.49E-06
5.00E-06

TOTAL HAZARD INDEX 4.29E - 01
                                         ^u mi«.ii» not of concern through thle«xpo»u» route.
                       NA - Not applicable. Chwnh»l I» "«     eonc.n,rat|on could not b. dstormlmd (APP.ndlx E).

-------
                                                     HAZARD QUOTIENTS AND INDICES
                                                     CURRENT UNPROTECTED WORKER
r1
w
SUBSTANCE
2-Chlorophenol
4-Chloropheno)
2.4-0
2 fl-D
2.4-Dichlorophenol
2.6-Dichlofophenol
Phanol
Sllvex
245-T
2.4,6-T
2.3.7.8-TCDD
Tetrachlorobenzene
2.3.6-Trlchlorophenol
2,4,5-Trlchlorophenol
2,4,6-Trlchlorophenol
, ..-r.nn IMPIFV (BY FXPOSURE ROUTE)
SOIL
INGESTION
3.82E-05
NA
1.52E-01
NA
8 15E-04
1.08E-04
NA
F 73E-03
i.2: E-02
NM
NTV
Nf
N/
NA
1 47E-05
1.66E-05
1.72E-01
DERMAL
ABSORPTION
FROM SOIL
7.63E-04
3.03E+00
NA
1.63E-02
2.15E-03
NA
1.35E-01
2.45E-01
NA
NTV
NA
NA
NA
2.94E-04
3.33E-04
3.43E+00
SOIL
INHALATION
4.73E-07
NA
1.88E-03
NA
1.01E-05
1.33E-06
NA
8.34t-05
1.52E-04
NA
NTV
NA
NA
NA
1.82E-07
2.06E-07
2.13E-03

VAPOR
INHALATION
8.22E-08
NA
NC
NA
2.22E-06
1.72E-07
NA
3.67E 07
1.96E-06
NA
NTV
NA
NA
NA
3.13E-07
1.96E-08
5.33E-06
DERMAL
ABSORPTION
FROM SURFACE
WATER
5.06E-03
1.16E-01
4.72E-02
1.50E-02
2.48E-01
3.09E-03
1.55E-CJ,
1.20E-C&
3.98E-02
7.99E-CC
NTV
NA
1.SOE-03
2.24E-05
8.81 E-03
2.91E-03
5.79E-01
HAZARD INDEX
(BY
SUBSTANCE)
5.86E-03
1.16E-01
3.23E+00
1 50E-02
2.66E-01
5.35E-03
1.55E-05
1 53d -01
2.97E-01
7.99E-02
NTV
NA
1 60E-03
2.24E-05
8.92E-03
3.26E-03

TOTAL HAZARD INDEX 4.19E+00
                                                  NA - Not applicable.  Chemical is not of concern through this exposure route.
                                                  NC - Not calculated because an exposure concentration could n<.. br determined (Appendix E).
                                                  NTV - Not calculated because an RfD was not available.

-------
                     HAZARD QUOTIENTS AND INDICES
                     FUTURE UNPROTECTED WORKER







H
is
CD
r1
w
ho
>__l
















SUBSTANCE
— — 	 ! 	 —
Acetone
Chloroform
2-Chlorophenol
4-CWorophenol
2.4-D
2,6-D
2,4-Dtehlorophenol
2,6-Dlchlorophenol
Methylene chloride
Phenol
SHvex
2,4,5-T
2,4,6-T
2,3,7.8-TCDD
Tefrachlorobenzene
Toluene
2 3 8-Trlchlorophenol
2 4,5-Trlchlorophenol
2,4,6-TrlcWorophenol

Antimony
Arsenic
Chromium
Copper
Lead
Mercury
.Nickel
Silver
Thallium
Zinc
. r-x/nstd IDC Qrtl JTE
^TftnnjMpnf (RY CVPQSURE ROUI ti

SOIL
INGESTION
^^-Des^raa^ttffi^
NA
NA
3.82E-05
NA
1.52E-01
NA
8.15E-04
1.08E-04
NA
NA
6.73E-03
1.22E-02
NA
NTV
NA
NA
NA
1.47E-05
1.66E-05
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA

1.72E-01


DERMAL
ABSORPTION
FROM SOIL
NA
NA
7.63E-04
NA
3.03E+00
NA
1.63E-02
2.15E-03
NA
NA
1.35E-01
2.45E-01
NA
NTV
NA
NA
NA
2.94E-04
3.33E-04
NA
LA
NA
NA
NA
NA
NA
NA
NA
NA

3.43E+00

SOIL
INHALATION
NA
NA
4.73E-07
NA
1.88E-03
NA
1.01E-05
1.33E-06
NA
NA
8.34E-05
1.52E-04
NA
NTV
NA
NA
NA
1.82E-07
2.06E-07
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA

2.13E-03

VAPOR
INHALATION
NA
NA
8.22E-08
NA
NC
NA
2.22E-06
3.72E-07
NA
NA
3.67E-07
1.96E-06
NA
NTV
NA
NA
NA
3.13E-07
1.96E-08
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA

5.33E-06

DERMAL
ABSORPTION
FROM SURFACF
WATER
NA
NA
5.06E-03
1.16E-01
4.72E-02
1.50E-02
2.48E-01
3.09E-03
NA
1.55E-05
1.20E-02
3.98E-02
7.99E-02
NTV
NA
1.60E-03
2.24E-05
8.61E-03
2.91E-03
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA

.79E-01

GROUNDWATER
INGESTION
1.57E-03
6.95E-03
3.13E+01
1.19E+02
1.57E+03
1.08E+03
1.89E+03
8.15E+01
2.12E-03
1.24E-01
1.35E+02
3.72E+02
i-OSE+02
NTV
3.26E+00
2.I5E+01
9. JOE -03
1.27E+01
9.69E-01
7.09E-01
1.83E-01
1.08E-02
3.70E-03
NTV
1.01E-02
2.40E-02
1.17E-02
NTV
2.05E-03

5.52E+03

HAZARD INDEX
(BY
SUBSTANCE)
1.57E-03
6.95E-03
3.13E+01
1.19E+02
1.57E+03
1 08E+03
1.89E+03
8.15E+01
2.12E-03
1.24E-01
1.35E + 02
3.72E+02
2.06E+02
NTV
3.26E+00
2.15E+01
9.32E-03
1.27E+01
9.72E-01
7.09E-01
1.83E-01
1.08E-02
3.70E-03
NTV
1.01E-02
2.40E-02
1.17E-02
NTV
2.05E-03


TOTA •_ HAZARD INDEX 5.52E + 03
NA - Not applicable. Chemical is not of concern through this exposure route.
NC - Not calculated because an exposure concentration could not be determined (Appendix E).
NTV - Not calculated because an RtD value was not available.

-------
      Factors  that  Tend  to  Overestimate Exposure/Risk;

 •     Use  of conservative exposure assumptions;

 •     Use  of conservative RfD's or SF's;

 •     Factors  that  could either Over or Underestimate
      Exposure/Risk;

 •     Use  of 1/2 the detection limit; and

 •     Possible occurrence of hotspots.

 6.3.6  Central Tendency Exposure

      In February 1992 a guidance memorandum from the Deputy
Administrator of EPA required that all Superfund risk assessments
evaluate both reasonable maximum exposure (RME) and central
tendency exposures.  Exposure assumptions in the ROD up to this
section have  been based on RME.   The central tendency scenario
represents the risk from more of an "average" exposure (see
Table 22).

6.4  ECOLOGICAL RISK ASSESSMENT

     The objective of the ecological risk assessment is to
identify and  estimate the potential for adverse ecological
effects to terrestrial  and aquatic flora and fauna from exposure
to hazardous  substances found in the soil and surface waters at
the Vertac site, including Rocky Branch Creek.  An ecological
risk assessment is subject to a wide variety of uncertainties.
Virtually ever step in  the risk assessment process involves
numerous assumptions that contribute to the total uncertainty in
the final evaluation of risk.  The uncertainty incorporated in
this assessment may result in an increase or decrease of the
estimation of potential ecological risks.  However, when
possible,  conservative  approaches are used in uncertain
situations.   The conservative method tends to increase the
estimated risk and therefore is protective of ecological
resources.  The substance of potential concern concentration
data, exposure assessment factors, and toxicity value selection
are the major contributors to uncertainty in the risk assessment.
Therefore, the ecological risk assessment for the OU2 media used
conservative, yet realistic, assumptions.

      In general, the approach for conducting the ecological risk
assessment parallels that used in the human health risk
assessment.   Habitats and  organisms potentially affected  by site-
related chemicals were  identified.  For  some  organisms, the risk
estimated was due  to direct  exposure to  site  chemicals, such  as
through ingestion  of site  surface water,  and  for other organisms
simple models were used to determine exposure to site

                                76

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                Summary of Potential Cancer Risks and Hazard Indices" —
                                   Central Tendency Case
Scenario
Trespasser
Current Unprotected Worker
Future Unprotected Worker
Total Lifetime Cancer Riskb
4E-06 (ChemRisk)
7E-05 OJ.S. EPA)
1E-05 (ChemRisk)
2E-04 (U.S. EPA)
2E-04 (ChemRisk)
2E-03 (V S. EPA)
Total Hazard Index
2E-02
2E-01
2E+03
'Values are rounded to one significant figure.
bChe"iRisk = Cancer risk was calculated using the slope factor for 23,7,8-TCDD developed by ChemRisk.
 U.S. EPA = Cancer risk was calculated using the slope factors for i3,7,8-TCDD developed by U.S. EPA.
                                         TABLE  22

-------
contaminants through  indirect exposure routes, such as eating
contaminated vegetation.  The potential for effects to occur was
evaluated by comparing benchmark criteria, such as acceptable
daily  intakes  to  estimated exposures.  This comparison resulted
in the calculation of hazard quotients.  In general, a hazard
quotient greater  than 1  indicated a potential for impacts to
occur  as a result of  exposure to a particular chemical.

     Potential ecological risks were evaluated for two mammalian
species and three avian  species.  The potential for adverse
ecological effects on aquatic fauna of the Rocky Branch Creek
were also estimated.  The results ->f the ecological risk
assessment showed that each of the organisms evaluated had a
hazard index exceeding the benchmark of 1.  The total hazard
indices for the ecological receptors evaluated ranged between 3.4
and 54.

     While this data  suggests that dioxin contaminated s^^iments
in Rocky Branch Creek have resulted in ecological impacts, until
the site is remediated and the source of dioxin contamination
eliminated,  the potential for -.ontinuing impacts exists through
contaminated surface  soils,  sediment transport and groundwater
seeps.   However,  with this remedy,  the primary source will be
removed through consolidation of dioxin contaminated soils in the
on-site landfill and  sediment transport resulting from the sump
overflows and storm water runon/runoff will be reduced or
eliminated through storm water management.

      Groundwater seeps from the contaminated areas of the site
into Rocky Branch Creek are currently impeded by the French Drain
system installed along the western edge of the site and bordering
the on-site burial grounds,  thereby preventing another potential
source of contamination for Rocky Branch Creek.   Stream data
indicates no measurable dioxin concentrations, for example,
following rain events.  Since Rocky Branch Creek is not a
perennial waterbody and does not flow through the site, the
removal of the contaminated soils and elimination of untreated
discharges and possible groundwater seeps will essentially
eliminate future  impacts.  While data suggests that existing
impacts in Rocky Branch Creek are on the decline, any actions to
remove contaminated sediments in Rocky Branch Creek would be cost
prohibitive, but more importantly, any disturbance of the
existing sediment could prove catastrophic, possible even
destroying the entire existing ecosystem.  As such, this remedy
in addition to the other on-going remedies at the site will
effectively remove the contamination source and the storm  water
transport concern allowing Rocky Branch Creek to continue,  in
essence, a natural attenuation process.

     In addition  to the  Ecological Risk Assessment, fish tissue
data collected for TCDD  from the Rocky Branch Creek/Bayou Meto
watershed areas near  the site suggest that contaminants  of

                                78

-------
 concern continue to pose an actual threat to  local  ecological
 receptors.   EPA issued a ROD in September 1990  addressing  the
 Vertac  off-site areas.   One of  the ROD  requirements was  to
 monitor fish in the streams for dioxin  and continue the  ban  on
 commercial  fishing and the  advisory that  discouraged  sport
 fishing as  long as fish tissue  dioxin levels  are above Food  and
 Drug  Administration (FDA) alert levels.   FDA  issued a health
 advisory stating that  fish  with 2,3,7,8-TCDD  >  50 parts  per
 trillion (ppt)  should  not be consumed,  and levels below  25 ppt
 pose  no serious health threat.   Based on  this guidance,  the
 Arkansas Department of Health (ADH)  has established an advisory
 level of 25  ppt in fish flesh.   The current advisory  encompasses
 Bayou Meto  from Arkansas Highway 13, upstream to the  mouth of the
 discharge from  Jacksonville West Wastewater Treatment Plant,
 including Rocky Branch Creek and Lake Dupree.

      Based on 1994  fish tissue  sampling results, dioxin
 concentrations  appeared to  generally decrease with  increasing
 distance  from the  site.  The highest dioxin concentrations were
 found in  Big Mouth  Buffalo  from Rocky Branch Creek  and Bayou Meto
 upstream  of Hwy  67-167.  The concentrations found were 73 ppt and
 94 ppt as TCDD TEQ's, respectively.  Concentrations of TCDD for
White Crappie at the Rocky  Branch Creek location was  26 ppt, and
 19 ppt for Large Mouth  Bass  at  the  Bayou Meto 67-167  location.
At the Arkansas Highway 161  location, TCDD  concentrations ranged
 from 22 to 36 ppt depending  upon the species of fish  sampled.

     In comparison, as  a part of EPA's National Bioaccumulation
Study (EPA,  1992),  fish data were collected to help identify
background levels of dioxin  in  fish.  Sixty fish samples were
collected from fresh and estuarine waters at a total  of 34 sites
away from points of obvious  industrial activity.  The average TEQ
was 1.2 ppt  (assuming half the  detection limit for non-detects).
When looking at all areas (not  just  pristine or background) EPA
 (1992) found an average of  11 ppt TEQ for  314 stations sampled.

 6.5  REMEDIAL ACTION GOALS

     A Remedial Action  Goal (RG) is a chemical-specific
 concentration for  each chemical of  concern that helps determine
 whether  a contaminated medium may  be left  in place  or must be
 addressed in the site  remediation  effort.   Media exhibiting
 contaminant concentrations  below the RG's  may be left in place
 without  treatment.   Those wastes that exceed  the RG's at the site
 will  be  addressed to meet requirements  set out  in the performance
 standards for each medium.

      Two different risk assessment approaches were  conducted for
 Vertac  soils  in order  to realistically  evaluate appropriate
 Remediation Goals (RG's) for site  contaminants  based  on  given
 land  use and exposure  assumptions.  The first method, Reasonable
 Maximum Exposure (RME), is  based on EPA risk assessment  guidance

                                 79

-------
 (see Risk Assessment  Guidance  for  Superfund: Volume I: Human
 Health  Evaluation Manual  (Part A)  (Interim Final, EPA/540/1-
 89/002, December 1989), and the  second method was based on Monte
 Carlo probabilistic risk  modeling.  Soil cleanup levels derived
 from these two risk assessment methodologies can differ for any
 given exposure scenario.   Examples of assumptions that go into
 the models to develop cleanup  standards include how often a
 person  visits a site, how long the person stays there during each
 visit,  how much soil  or dust a person is exposed to at the site,
 how contaminated the  soil is,  and how hazardous the contamination
 in the  soil is.  One  of the principle differences between the two
 risk assessment methodologies  is that RME uses one combination of
 values  for each of these  input assumptions (which is high but
 reasonably possible), and Monte Carlo uses a wide range of values
 for each input parameter.

     Over the past year,  EPA has met on numerous occasions with
 various local civic groups and community leaders to discuss
 cleanup activities at the Vertac site.  One common element from
 those discussions included concern over the potential for future
 commercial redevelopment  of the site,  or portions of the site.
 See discussion at Sections 3.0 and 4.0 above.  With that in mind,
 EPA has developed soil cleanup goals for dioxin at the Vertac
 Site that would be protective  for a worker in a
 commercial/industrial setting.  EPA acknowledges that certain
portions of the site will be unavailable for potential future
 redevelopment, i.e.. areas that house landfills, and areas that
 are otherwise encumbered by long-term remediation or other
perpetual operations and maintenance.   Also,  input from the
community stressed that the workers required to maintain these
restricted portions of the site should also be protected to a
 commercial/industrial level and not be required to wear
 "moonsuits" to conduct their activities in the community.
Anotht- community concern is that t.ie smallest area possible be
 fenced so that future potential commercial/industrial development
 is possible.  EPA expects the  fence along Marshall Road will be
moved west in phases as the remedial action completion allows.
 However, EPA will not know until the remedial design phase of the
 OU2 remediation the precise location of the fence it will require
 Hercules, Inc., to install.  With this in mind EPA analyzed the
 risk for a "casual passerby".  EPA has concluded that any future
 passerby is fully protected by any risks from the site.  See
 Section 6.3.2 - Casual Passerby.

     The two primary  contaminants  in Vertac soils that will
 require remediation are dioxins  and furans as 2,3,7,8-TCDD
 toxicity equivalents  (TEQ's),  and  tetrachlorobenzene  (TCB).  TCDD
 contamination is present  across  a  wide area of  the  site  and was
 an unwanted byproduct from the production of the herbicide
 2,4,5-T.  TCB contamination, however, is only found in a
 localized area or "hot  spot" and is the result  of a railroad tank
 car spill.  RG's were not developed for other contaminants  of

                                80

-------
 concern at the site because they  will  be  well  below health-based
 action levels after dioxin remediation takes place.

      Following is  a summary of  EPA's risk evaluation used  to  set
 site remediation goals  for dioxin and  furans  (TEQ)  at Vertac.

      EPA evaluated a 50 ppb,  20 ppb, and  a 5 ppb as  not-to-exceed
 cleanup values for TCDD (TEQ) at  the Vertac site using both RME
 and  Monte Carlo risk analysis.  Some of the assumptions used  in
 the  modelling included  a worker scenario,  non-detects were
 counted as 0.15 ppb (1/2 the  detection limit), and that all
 remediated grids would  be  replaced with clean  fill.   Table 23
 presents all  the parameters and values u^ed in the RME
 calculations  and Table  24  presents the parameters and values used
 in the  Monte  Carlo calculations.   An  RME  and  Monte  Carlo
 simulation was run for  each of  the soil cleanup levels and the
 results of those analyses  are shown in Table 25.

     The RME  results  show  that  the excess  lifetime cancer risk
 associated with  an average exposure point  concentration of 50,
 20, and 5  ppb, are 7.6  x 10-3,  3.0 x 10-3,  and 7.6 x  10-4
 respectively.  Compared to RME  risks,  the Monte Carlo simulation
 risks were 3.1 x 10-3,  1.2  x 10-3, and  3.1  x 10-4 respectively
 using the  95% probability  distribution  point when Monte Carlo
 analyses are run with the  fixed point  concentrations of 50, 20,
 and 5 ppb  respectively.  These  results  also support the
 conclusion that  any risk posed to a casual passerby  is well
within  EPA's acceptable  risk range.

     In order to more realistically evaluate the exposure
 concentration of a person  at the site,   grid averaging was
 employed to determine the  actual exposure concentration,  rather
 than defau1ting  to the  cleanup goal as  the  exposure point
 concentration.   In order to accomplish  this, EPA next ran both
 the RME and Monte  Carlo  simulations on  the  arithmetic mean (using
 the 95% upper  confidence limit  (UCL95;   of dioxin that would be
 present  at the site after  remediation.   For not-to-exceed cleanup
 values  of  50,  20,  and 5  ppb, arithmetic mean values  of 2.92, 1.8
 and 0.676  ppb were obtained.  The RME  excess cancer  risks
 associated with  2.92, 1.8,  and  0.675 ppb were  4.4 x  10-4, 2.7 x
 10-4 and 1.0 x 10-4 respectively.

     For the Monte Carlo analysis, the lognormal distribution of
 these residual grids  were  used  as the  concentration  term,  and the
 excess  lifetime  cancer  risk at  the 95% probability distribution
 were 1.8  x 10-4, 1.1  x  10-4,  and  4.1 x 10-5 for not  to exceed
 values  of 50,  20,  and 5 ppb.  Table 26 depicts the RG's developed
 for the Vertac site.
                                81

-------
ta
w
             n^v-amo^rs  and Values  Used in the RME Risk Calculations Assuming  a
    u   «.*, *<«! Sorker  Scenario  Exposed Through Oral and Dermal Routes to  Soil
    gonŁam?naŁed v?"*  '-"%.8-TCDD  TEQS at Vertac, Inc. Superfund Site.	
    Parameter
     Concentration (C,)
     Conversion Factor (CF)
 Fraction^
 Body Weight
Averaging Time (AT^
Dermal Slope Factor
 Oral Cl"pa Factor (SF^
                             d)
                                   Units
                                       mg/kg
                                   kg/mg
                                       cm
                                       Unitless
                                   years
                                   days/year
                                        Unitless
                                        Unitless
                                        kg
                                        days
                                    /ing/kg/day
                                    /mg/kg/day
Value
                                                     0.005
 1E-06
                                                         5000
                                                    0.03
  250
                                                                 Source
           Soil Cleanup level
                                                             US EPA, 19891
                                                             US  EPA,  19922
                                                                     EPA, 1992
          US EPA, 1992
                                                                  US EPA, 19913
                                                             US EPA,  1991
                                                                  US EPA, 1991
                                                     0.5
                                                          25550
                                                          284000
                                                          156000
                                                              UC EPA,
          US  EPA,  1989
                                                              UJ EPA, 199la4
                                                              US EPA, 199la
           US EPA,  1992
           US EPA, 19945
           . ,l1sted by the following equations,  adapted from EPA guidances*1 •2-3-4>
Risk was calcuiatea uy

Risk *  (
                         BW * AT
                                     L-*-
                                      BW
                                      I * ABS0 * EF * ED * SF0 )
                                      AT

-------
H
s
r<
N3
•P-
                            ^ U
                     rke'r ISena
                   %rt«c  '"•-
      Parameter
                      Units
      2,3,7,8,-TCDD
      TEQs

      Adult Skin
      Surface Area
ci2
      Fraction of
      Skin  Exposed
                                                         25550
                                                         0.287
                                                          50
Monte Carlo Simulations and RME Risk Calculations Assuming a
rough Oral and Denal Routes to Soil Contaminated v tth 2,3,7,8-
e.
te Carlo
verage
74
49
49
>4
)155
0
B*.
.9
Monte Carlo
95th %le
2.1
18194
0.329
1.2
0.0286
250
34.4
88.5
Distribution
Type
Log normal
Lognormal
Uniform
Triangular
Uniform
Fixed Point
Estimate
Cumulative
Lognormal
Distribution
parameter?
M * 0.674
SD = 0.8739
Males
M = 19400
SD = 37.4
Females
M = 16900
SD = 37.4
Min. = 0.161
Max. = 0.338
Min. = 0.2
Best =0.2
Max. = 1.5
Min. = O.T01
Max. = O.oJ

Min. = 0
I Max. = 48
Males
GM =ln 76.71
GSD = In1.19
Females
Source
Site
data
USEPA,
1992
USEPA,
1992
USEPA,
1992
USEPA,
1992
USEPA,
1991
HERCULES
1994
Smith,
1994
Fixed Point
Estimate

Unifonm
                                                   Fixed  Point
                                                   Estimate
                                                                                       GM =ln 64.72
                                                                                       GSD =ln1.22
                                                                 Min.  =  0.05
                                                                 Max.  =  0.3
USEPA,
1991

HERCULES
1994

USEPA,
1991

-------
03
r1
O
o
3
     Parameter


     Fraction Soil
     Contaminated
Unitless
                               Used in Monte Carlo Simulations  and RME Risk C.- 'culations Assuming a
                                      -1-——- s°u c  ~" ™
                            7.5E-04
Monte Carlo
Average
0.5
1.0E-06
1.0E-05
1.0E-05
Monte Carlo
95th %le
0.5
4.1E-06
4.1E-05
4.1E-05
Distribution
Type
Fixed Point
Estimate



Distribution
parameters




Source
USEPA,
1989



     H =
                   tandard   viation. UM = beo»etric Meai, U5U = ueo.etric Standard Deviation.

-------
                  Pathways
          Comparison of
         Expj

Type of Risk
Estimate
Fixed Point RME
                                    (RME) and Monte  Carlo  Risk Estimates - Worker
                                            Ingestion Plus Dermal Contact with Soil.*
Fixed Point RME
Using 95% UCL on the
Arithmetic mean of
residual grids.

Monte Carlo

Lognornal
Distribution of
Residual Grids
     Average
      Maximum
      Minimum
 Percenti*tes_

      25

      50 %_

      75A
       95  %
      100 %
         from
 negligible
                      Lifetime Cancer Risk
                      Soil Ł50 ppb Removed
Cleanup - 50 ppb

     7.6E-03

Cleanup = 2.92 ppb


     4.4E-04
 Ave  =3.210,  SD-6.840
 Monte  Carlo  Ave=3.12
 Monte  Carltt_95t"H.l
Cleanup =20 ppb

     3.0E-03

     mp = 1.


     2.7E-04
cer Risk
Removed
ppb
8 ppb
Lifetime Cancer Risk
Soil Ł5 ppb Removed
Cleanup = 5 ppb
7.6E-04
Cleanup = 0.675 ppb
l.OE-04
      5.1E-09
      3 . IE- 06

       .OE-05
                             9.6E-5
 Ave=1.933,  SD= 3.610
 Monte Carlo Ave=1.90
 Monte Carlo 95%=6.6
                            2.7E-05
                            3.8E-03
                             8.5E-09
                                                                    Ave=0.674,  SD=0.8739
                                                                    Monte CarloAve=0.674
                                                                    Monte Carlo 95%=2.1
                                                   l.OE-05
                                                   1.3E-03
                                                   4.7E-09
                             1.8E-04
                             3.9E-03
                             2.0E-06
      6.5E-06
                             2.0E-05
                             6.1E-05
                                                   1.1E-04
                             3.8E-03
                      Con  01
       SO]
             was not  consi<
                                                         Lnce risk
                                                    9.3E-07
                             2.8E-06
                                                    8.4E-06
                              2?3E-05
                                                    4.1E-05
                       	1.3E-04	
                       througn  this "route
                                                                                         is

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    Table 26.  Remediation Goals for Contaminated Soil Media,
CONTAMINANT
Dioxins & Furans (TEQ)
Tetrachlorobenzene
REMEDIATION GOAL
5 ppb
500 ppm
     Information from EPA's site specific risk assessment showed
that a RG of 5 ppb TEQ for dioxin was necessary to be protective
for a worker exposure scenario.  The ris\ associated with a not-
to-exceed soil cleanup value of 5 ppb dioxin ranged from between
1X10"1 to 4X10-5.

     A second soil RG was also established for tetrachlorobenzene
(TCB) associated with a spill area at the site.  All crystalline
TCB, and TCB in site soils greater tLan 500 ppm would be
excavated and treated off-site.

7.0  DESCRIPTION OP ALTERNATIVES

7.1  ALTERNATIVES

     Alternatives for remediation were developed in the FS by
assessing technologies and the range of media to which they would
be applied.   The FS considered separate "stand alone"
alternatives for the two media addressed by Operable Unit 2, they
are:

•    Soils - There are two components to the soils alternatives.
     The first component involves both on-site surface and
     subsurface soils that have not yet been excavated and bagged
     soils excavated from contiguous off-site residential
     properties as part of an earlier removal action.  These
     bagged soils are discussed in the FS for OU1, and the OUl
     ROD deferred the treatment of those soils until all site
     soils were to be addressed.

     The second component involves an amendment to the 1990 ROD
     for Off-Site Areas, which had selected incineration as the
     treatment method for contaminated soils and debris from
     contiguous portions of Rocky Branch Creek, sludges removed
     from the sewage treatment plant and sediments from the sewer
     interceptor lines.  The sewage treatment plant  sludges and
     the sediments from the sewer lines are considered to be
     contiguous to and within the site's area of  contamination
     (AOC) due to the continuous connection from  the site to  the
     sewage treatment plant by way of the  sewer line.
                                86

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      The  Agency intentionally deferred treating  those  materials
      from the  Off-Site  ROD  until  all  site  soils  were to  be
      addressed.   In addition,  the on-site  incinerator  is no
      longer operational,  the  1990 Off -Site ROD materials came
      from contiguous areas  within the site's AOC,  and  the
      materials are  similar  to the contaminated soils and debris
      addressed in this  ROD.   Therefore, EPA has  determined that
      these materials are  appropriately addressed in a  manner
      consistent with the  remedy selected for this  operable unit.
      For  those reasons, in  conjunction with this ROD,  the EPA
      will also amend the  1990  Off-Site ROD to reflect  the change
      in approach.

•     Underground Structures -  this includes underground
      utilities,  foundations, curbs, and pads.  (As discussed
      above, Hercules, Inc., has .recently addressed the fuel
      storage tanks by draining them and filling  the drained tanks
      with flowable grout  so as to prevent  any possible leakage of
      residues.   Therefore, this ROD need not address those tanks
      as had been proposed in the FS . )

SOILS

     The  following is a summary of the  soils alternatives
presented  in the  FS.  A more detailed description of the
alternatives can be found in the OU2 FS report itself.

     The alternatives evaluated in the FS differed from one
another principally in two ways:  First by the cleanup level
presented  for TCDD in soils (i.e.  . the  level of TCDD that would
be left on the ground after remediation to be protective for a
specific future  site use)  , and secondly; by the concentration of
TCDD  in soils that would be subjected to various treatment,
containment, and/or capping options.

     Three series of action levels for TCDD in site soils were
presented  in the  FS for many of the alternatives evaluated.
These action levels were presented by Hercules in the FS  as a
guide for  costing purposes only.  The cleanup levels for  the
site, however, were established by EPA  after evaluating the risk
assessment.  EPA made those decisions  after the  completion of the
FS, which presented the entire universe of possible alternatives.
However,  not all of those alternatives  remain under consideration
after initial  screening by  EPA.
           27 presents a summary of the soils alternatives
evaluated for this ROD, and Tabl« 28 presents a  summary  of  the
quantities of materials addressed by the various treatment
options.

     This ROD will address on-site soils and underground
utilities and the contaminated  soils and debris  from the 1990

                                87

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H
f
w
                                                                                T»blc 27
                                                              SUMMARY SURFACE SOILS ALTERNATIVES
                                                                    Consolidation
                                                                     TCDD>500
                                                                     Bagged SoiU
                                                                     TCDD>200
                                                                     Bagged Soib
                                                                  50050
                                                                      Bagged SoiU
                                                                       TCDD>20
                                                                       Bagged Soils
  Desorption
 TCDD>2000
TCB Spill Soib
 TCDD>1000
TCB Spill Soib
 TCDD>2000
TCB Spill Soils
  TCDD>50
TCB Spill Soib
                                                                                         TCDD>20
                                                                                         Bagged Soib
                                                                                        TCB Spill Soib
 Dechlori nation
Desorbed TCDD-
 related liquids
Desoibed TCDD-
 relale- 1 liquids
Desoibed TCDD-
 relaled liquids
                                                                                                                                Onsite Incin
                                        TCDD>2000
                                        TCDD>1000
                                         Offsite Incin
                                                          Ciyitalline TCB
                                                         A Spill Soib
                                                           Crystalline TCB
                                                          & Spill Soib
Crystalline TCB
 desorbed TCB
Crystalline TCB
 deiorbed TCB
Crystalline TCB
 desorbed TCB
                                                           Crystalline TCB
                                                          & Spill Soib
                                                           Crystalline TCB
                                                          t Spill Soib
                                         Crystalline &
                                        desorbed TCB &
                                       TCDD ocndensate
                                                            Crystalline ft
                                                           desorbed TCB *
                                                          TCDD condensate
                                                             TCDD > 50
                                                           Crystalline TCB
                                                             A. Spill Soib
                                                                                                                                                     TCDD > 20
                                                                                                                                                    Bagged Soib
                                                                                                                                                   Crystalline TCB
                                                                                                                                                     & Spill Soib
                                                            Crystalline TCB
                                                             & Spill Soib
                                                            Crystalline TCB
                                                             & Spill Soib
                                                            Crystalline TCB
                                                              & Spill Soib
                                                            Crystalline TCB
                                                              & Spill SoiU

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                                                                   Table 28
                                       SUMMARY OF QUANTITIES OF MATERIALS UNDER SOILS ALTERNATIVES
w

K3
00

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Off-Site Areas ROD  (sludges from the sewage treatment plant and
sediments from the  interceptor lines), soil? that will be
excavated from Rocky Branch Creek flood plain deferred in the
1993 OU1 ROD, and bagged soils removed from contiguous
residential areas as part of a removal action conducted by
Hercules, Inc.  The disposition of the 1990 Off-Site Areas ROD
materials and the bagged residential soils Hercules had excavated
as part of a 1990 removal action was deferred in both the 1990
Off-Site Areas and the 1993 OU1 RODs, and also was evaluated in
the Operable Unit 2 FS, because those materials are essentially
identical media as OU2 soils in that they also constitute low
level threat media as discussed in Section 4.0 above.  One should
note that the decision to address the disposition of the 1990
Off-Site Areas ROD materials as part of the ROD for OU2 does not
alter any other aspects of the 1990 Off-Site Areas ROD, such as
the l ppb TCDD cleanup level for flood plain soils.

Alternative l       Mo Action

DESCRIPTION

     The no action alternative for OU2 media at the site provides
a basis for comparing existing site conditions with those
resulting from implementation of the other proposed alternatives.
Under the no action alternative,  no additional measures would be
used to remediate contaminant sources.   Access to the site would
be prohibited only by the existing site fence.  Therefore, public
access would only be passively restricted.  No institutional
controls,  facility maintenance, or monitoring would be
implemented, except for those being performed in accordance with
the 1984 Court Order.

     Implementing no remedial activities for the OU2 media at the
site allows the existing contaminant sources to remain in place.
The potential for exposure to contaminants is not reduced under
this alternative.

     The Superfund program requires that a no action alternative
be considered at every site as a basis of comparison when
evaluating other alternatives.  This alternative would not
decrease the toxicity, mobility, or volume of contaminants or
reduce public health or environmental risks to acceptable levels.
Also, this alternative would not comply with State and Federal
environmental regulations, and therefore, is not favored by EPA.

COST AND TIME OF IMPLEMENTATION

     Capital Cost:                            $0
     Operation and  Maintenance:               $0
     Total  Cost:                              $0

     Time of Implementation:                   0  years

                                90

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Alternative  8-2     Containment and Consolidation

DESCRIPTION

     Under this  alternative, no action would be applied to
surface  soils with a TCDD concentration of 50 ppb or less.
Surface  soils exceeding the action level of 50 ppb but less than
500 ppb  TCDD would be covered with a 12 inch thick layer of clean
soil to  prevent  direct exposure and to reduce the potential for
surface  migration of contaminated soil (see Figure 11).

     The 10-fold range in the action level addressed by the soil
cover is based on the assumption that if the soil is disturbed by
site workers, the contaminated soil would be diluted by a ratio
of 10 to 1 dilution with the clean soil before exposure to
workers  occurs.  The 10 to 1 dilution would yield an exposure
concentration and therefore an equivalent risk of exposure to
below the action level.  This approach is consistent with that
applied  by EPA for dioxin-contaminated soils at other CERCLA
sites in Region  6, such as the related RODs for both the
Jacksonville and Rogers Road Municipal Landfill sites.  In
addition, a  10-fold increase in the dioxin level for soils below
a depth of 1 foot was also used by EPA for the Missouri dioxin
sites.

     Under this alternative,  surface soils to a depth of one foot
below ground surface exceeding 500 ppb TCDD and bagged
residential soils Hercules had excavated as part of a 1990
removal action from contiguous residential areas would be
consolidated (landfilled)  on-site.  Excavated areas would be
backfilled to grade using clean soil and revegetated.  The
excavated materials would be placed into the
consolidation/containment unit (CCU)  whic>> was included as part
of the selected remedy for certain OU1 materials.   As described
in greater detail in the portion of Section 7.2 below entitled
"Consolidation," although dioxin-contaminated media constitute a
listed RCRA waste whose applicable land disposal restriction
(LDR)  treatment  standard is defined at 40 CFR 5 268.31, those
requirements are not applicable due to the fact that placement,
the triggering element for the imposition of LDR's, will not take
place.    This is  due to the fact that all media proposed to be
consolidated within the on-site RCRA Subtitle C hazardous waste
landfill come from within the site's area of contamination  (AOC),
or fall  below the 5 ppb treatability variance range  EPA has
selected for dioxin-contaminated Vertac media in a July 18, 1996,
Action Memorandum found in the Administrative Record.  The  CCU
presented in the OU2 FS would be  a modification or enlargement of
the CCU  to be constructed for OU1 materials.  Modifications to
the CCU  would incorporate design  standards required  for a RCRA
Subtitle C hazardous waste landfill  (see Figure 12).
Nonetheless, the CCU will meet all applicable substantive RCRA
                                91

-------
PJ
                                                              Vegetation
                                                                     -

                                                                Topsoil
                                                                       -77- xV\

: Grid Bounda   :
\'  •    \    riginal Surface So
                                                                             '' '     '    '    C ',\ '.lj ' Grid
.'V,,,N-i  Original Surface Soils  . , x._,^, x ^ x.  ^ , ^._,^ x  ,p-«^ ' •-_»,- •• •, » t- -»v- _»,' - ",

•//V'XX",V-'/V'''^I^~'/\'''NI\~  N' x ' 1 x >  x ~  j'\''^»^~'/\''-xi»~  ,
  \x  * \ ,  - ' v ,  ^ ' ' f  - '  ,  ^ ' ' '   - "  , ^ ' ' -   - ' I . ^ ' ' •   -  - V    '*s  - -

 _ v I  ~ -  ^x  ' - x '_  -  ' ^ , ' ~ * ~  ~  ' 2 , ' ~ *  -    ' - ,' ~ \ ~    ' ^  '  - x ' " -  -^ '  - -


^'" " ' ~~' i .  L  '" ''/" x' ,' -  '-  ' ''/" x' ,' -x 1 ' '',"!.,'- ~ ^ -\^ ^,' - L ^ -'/''-'- ^  -'
                                                                                                                  Not to Scale
                                               CONCEPTUAL DIAGRAM OF SOIL COVER - CROSS-SECTION

-------
                 Gas Vent
                 Leachate
                 Collection System
                 Primary FML
                 (80 Mil)


                 12" Sand for
                 Lateral Drainage
                 Leachate Detection
                 System
                 Secondary FML
                 (80 Mil)

                 36" Clay (10 7cm/sec)
                 Liner
Approximate Height Above
Ground Surface = 30'
    12" Topsoil/Vegatative Cover


      6" Sand for Lateral Drainage

            36" Clay (10 7 cm/sec) Cap


                Waste i ayer


                     Slope = 3:1
                                                                                               12" Sand for
                                                                                               Lateral Drainage
                                                                                                      Ground
                                                                                                      Surface
94P-1307  3/4/94
                         DOUBLE-LINED CONSOLIDATION/CONTAINMENT UNIT - CONCEPTUAL CROSS-SECTION

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standards  for  the design,  construction, and operation of a
hazardous  waste  landfill found at 40 CFR Part 264.

     Except  for  the TCB spill area, subsurface soils at depths.
greater than 1 foot below  the ground surface would remain in
place because  there are no direct exposure pathways to subsurface
soils.  An indirect exposure pathway is present through the
potential  migration of site compounds from these soils into
ground water.  However, site-related compounds, especially TCDD,
bind tightly to  the soils  and are not considered very mobile.

     The crystalline TCB and associated soils exceeding the
action level of  500 ppm will be excavated and transported off-
site for incineration at a RCRA-permitted facility.  The
treatment  residuals from the TCB and related soils would be
disposed of  by the off-site facility that performs the treatment.

     Administrative and engineering control of site access would
be implemented.  Administrative controls would include deed
notifications  to limit future land use for the portion of the
property that  will remain  fen~-d.  Engineering controls would
include maintenance of the following:  The site fence,  engineered
structures proposed under OU1 (i.e..  the CCU), and the soil and
vegetative cover over areas that received clean backfill after
excavation of  the dioxin-contaminated soil, and any other
backfill necessary to achieve final site grading to facilitate
positive drainage.  Monitoring and maintenance of the site would
also be performed.

     Alternative S-2 reduces potential exposure to target
compounds at the site through off-site treatment of TCB
contamination  and consolidation or containment of TCDD-
contaminated soils.   Under this alternative approximately 83
percent of the TCDD-contaminated soil will be covered or
isolated.   Implementation  of this alternative and the options to
this alternative effectively address the low level threats posed
by the media subject to the OU2 ROD by containing, versus
treating,  those media within the RCRA Subtitle C hazardous waste
landfill.   This approach is expressly endorsed for low level
threat wastes  whose treatment is impracticable at NCP Section
300.430(a)(iii)(B),  40 CFR S 300.430(a)(iii)(B), which states:

     EPA expects: to use engineering controls, such as
     containment, for wastes that pose a relatively low long-term
     threat  or where treatment is impracticable.

COST AND TIME  OF IMPLEMENTATION

     Total Capital Cost:                      $5,896,000
     Operation and Maintenance:                  $37,700
     Total Present Worth:                     $6,500,000  (rounded)
     Time  of Implementation:                     2  years

                                94

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 Alternative 8-2,  Option A

 DESCRIPTION

      Option A provides  the  same  remedial  actions  for the OU2
 soils as Alternative S-2 except  with different action levels for
 TCDD.   Bagged soils  from contiguous residential areas and
 crystalline TCB and  spill-related  soils would be  the same as that
 described  for Alternative S-2.   For Alternative S-2A, only
 surface soils with TCDD concentrations above 20 ppb would be
 addressed.   Those surface soils  greater than 200  ppb TCDD would
 be excavated and  placed in  the on-site CCU, and those soils with
 concentrations greater  than 20 ppb, but less than or equal to 200
 ppb, would  be covered (capped with clean backfill) in place.

 COST AND TIME OF  IMPLEMENTATION

     Total  Capital Cost:                     $6,398,000
     Operation and Maintenance:                 $37,700
     Total  Present Worth:                    $7,000,000 (rounded)

     Time of  Implementation:                    2 years

Alternative 8-3     Containment, Consolidation and On-site
                    Desorption and Chemical Treatment

DESCRIPTION

     This alternative is the same as S-2,  with the following key
differences.   Surface soils with concentrations of TCDD exceeding
2,000 ppb will be treated on-site.   Two options to this
alternative are evaluated, Alternatives S-3A and S-3B,  which use
the same remedial approach but are based <~>r> different action
levels.  Treating soils with concentrations of TCDD greater than
2,000 ppb would permanently reduce toxicity, mobility,  and volume
of a large  portion of the TCDD.  The on-site treatment process
would consist  of thermal desorption of the soils to extract the
organic compounds, including TCDD.   The organic compounds would
exit the treatment process  as a condensate which will be treated
by chemical dechlorination.  Chemical dechlorinate residuals
would be incinerated off-site.  The treated soil  residuals would
be considered to be clean and would be used in the CCU as fill,
or they would be delisted and used on the site for grading
purposes.

     Soils  associated with  the TCB spill would be desorbed on-
 site, with  the desorption residuals incinerated off-site.
Crystalline TCB would be sent off-site for treatment at a
permitted facility.
                                95

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                                             $8,546,000
                                                $37,700
                                             $9,100,000  (rounded)

                                                3 years
COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:
     Operation and Maintenance:
     Total Present Worth:

     Time of Implementation:

Alternative 8-3, Option A

DESCRIPTION

     Alternative S-3A would address surface soils with TCDD
concentrations greater than 20 ppb.  Surface soils with TCDD
concentrations greater than 1,000 ppb would be subjected to on-
site thermal desorption.  Soils with TCDD concentrations greater
than 200 ppb and less than or equal to 1,000 ppb would be
excavated and consolidated in the on-site CCU.  Surface soils
with TCDD concentrations greater than 20 ppb but less than or
equal to 200 ppb would be left in place and covered with a one
foot thick soil cover.  Other media such as the bagged soils from
contiguous residential areas,  crystalline TCB, and spill-related
soils would be treated the same as under Alternative S-3.
COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:
     Operation and Maintenance:
     Total Present Worth:

     Time of Implementation:
Alternative 8-3, Option B
                                             $9,396,000
                                                $37,700
                                            $10,000,000 (rounded)

                                                3 years
     Alternative S-3B provides for on-site thermal desorption of
surface soils with TCDD concentrations in excess of 2,000 ppb,
consolidation in the on-site CCU of surface soils with TCDD
concentrations between 350 ppb and 2,000 ppb, and covering of
surface soils with TCDD concentrations greater than 35 ppb.
Other media such as the bagged soils from contiguous residential
areas, crystalline TCB, and spill-related soils would be treated
the same as Alternative S-3.
COST AND TIME OF  IMPLEMENTATION

     Total Capital  Cost:
     Operation  and  Maintenance:
     Total Present  Worth:

     Time of Implementation:
                                              $8,687,000
                                                 $37,700
                                              $9,300,000  (rounded)

                                                 3  years
                                96

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Alternative 8-4     Containment, Consolidation and On-site
                    Incineration

DESCRIPTION

     The actions described under Alternative S-3 would be
implemented under this alternative except that on-site
incineration would be used in place of thermal desorption and
dechlorination for surface soils with TCDD concentrations
exceeding 2,000 ppb.  One option to this alternative, Alternative
S-4A, was also evaluated.  The soils associated with the TCB
spill exceeding 500 ppm and the crystalline TCB would be
transported to an off-site incineration tacility for treatment
because of their non-F listing.  Residuals resulting from on-site
incineration would be consolidated with other OU2 media in the
ecu.

COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:                     $8,900,000
     Operation and Maintenance:                 $37,700
     Total Present Worth:                    $9,500,000 (rounded)

     Time of Implementation:                     3 years


Alternative 8-4, Option A

DESCRIPTION

     Surface soils with TCDD concentrations in excess of 1,000
ppb would be treated by an off-site incinerator.  Surface soils
"\th TCDD concentrations greater than 200 ppt vut less than or
equal to 1,000 ppb would be placed into the on-site CCU.  Soils
exceeding 20 ppb TCDD but less than or equal to 200 ppb would be
covered in place.

COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:                    $10,959,000
     Operation and Maintenance:                  $37,700
     Total Present Worth:                   $11,500,000  (rounded)

     Time of Implementation:                     3 years

Alternative 8-5     On-site  Desorption with Off-site incineration

DESCRIPTION

     Under this alternative, surface soils with TCDD
concentrations  above  50 ppb and soils associated with the TCB
spill would be  excavated and treated on-site by thermal

                                97

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desorption.  One option to this alternative, Alternative S-5A,
was also evaluated.  The condensate from the thermal desorption
process would be transported off-site for incineration at a RCRA-
permitted facility.  The treatment residues would be disposed of
by the treatment facility.  The soils from OU1 would be placed
into the on-site CCU.
                                            $14,603,000
                                                $10,400
                                            $14,800,000 (rounded)

                                                4 years
COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:
     Operation and Maintenance:
     Total Present Worth:

     Time of Implementation:

Alternative 8-5, Option A

DESCRIPTION

     Alternative S-5A provides for the same excavation, on-site
treatment, and off-site incineration for the surface soils as
Alternative S-5, except that a lower action level of 20 ppb for
TCDD applies.  Bagged soils from contiguous residential areas and
TCB spill soils would also be treated using the on-site thermal
desorption process.
COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:
     Operation and Maintenance:
     Total Present Worth:

     Time of Implementation:
                                                 $26,636,000
                                                $10,400
                                            $26,800,000 (rounded)

                                                4 vears
Alternative 8-6
DESCRIPTION
                    Off-site Incineration
     Under this alternative, surface soils with TCDD
concentrations above 50 ppb, crystalline TCB, and the soils
associated with the TCB spill exceeding 500 ppm would be
excavated and incinerated off-site at a RCRA permitted  facility.
One option to this alternative, Alternative S-6A, was also
evaluated.  Treatment residues from off-site incineration would
be disposed of by the off-site treatment facility.  The bagged
soils  from contiguous residential areas would be consolidated
into the on-site CCU.
                                98

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COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:                    $62,089,000
     Operation and Maintenance:                 $10,400
     Total Present Worth:                   $62,200,000 (rounded)
     Time of Implementation:                    5 years

Alternative 8-6, Option A

DESCRIPTION

     Alternative S-6A provides for the same excavation and off-
site incineration for the surface soils,  but applies to a lower
action level of 20 ppb TCDD.
                                           $164,601,000
                                                $10,400
                                           $164,800,000 (rounded)

                                                5 years
COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:
     Operation and Maintenance:
     Total Present Worth:

     Time of Implementation:

Alternative 8-7     Containment (Capping)

DESCRIPTION

     Under this alternative, no action would be applied to
surface soils with a TCDD concentration of 50 ppb or less.  The
surface soils exceeding the action level of 50 ppb TCDD would be
covered with a 12 inch layer of clean soil to prevent direct
exposure and reduce the potential for migration of surface soils
due to rair fall and wind.  An option to this alternative, S-7A,
would use the same remedial approach but with different TCDD
action levels was also evaluated.

     '^he crystalline TCB and associated TCB spill-related soils
exceeding the action level of 500 ppm would be excavated and
transported off-site for incineration at a RCRA permitted
facility.  Following treatment of the TCB and associated  soils,
the residuals would be disposed of oy the off-site treatment
facility.

     Administrative and  engineering  control  of site  access  as
described  in Alternative S-2 would also  be  implemented.
                                99

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COST AND TIME OF  IMPLEMENTATION

     Total Capital Cost:                     $5,698,000
     Operation and Maintenance:                 $37,700
     Total Present Worth:                    $6,300,000  (rounded)
     Time of Implementation:                    2 years

Alternative 8-7,  Option A

DESCRIPTION

     Alternative  S-7A provides for the same remedial actions as
Alternative S-7,  except with different action levels for TCDD.
Surface soils with TCDD concentrations above 20 ppb would be
addressed by the  remedial action.  Specifically, those surface
soils with TCDD concentrations above 20 ppb would be covered in
place with a 12 inch layer of clean soil to prevent direct
exposure and reduce the potential for migration of surface soils
due to rainfall and wind..  Bagged soils from contiguous
residential areas and crystalline TCB and TCB spill-related soils
would be addressed in the --me manner as described under
Alternative S-7.

COST AND TIME OF  IMPLEMENTATION

     Total Capital Cost:                     $6,076,000
     Operation and Maintenance:                 $37,700
     Total Present Worth:                    $6,700,000  (rounded)

     Time of Implementation:                    2 years

Alternative 8-8     Consolidation (Landfilling)

DESCRIPTION

     Under this alternative, no action would be applied to
surface soils with a TCDD concentration of 50 ppb or less.  The
surface soils exceeding the action level of 50 ppb TCDD would be
excavated to a depth of 1 foot and consolidated on-site  in the
CCU.  As an option to this alternative, Alternative S-8A would
employ the same remedial approach as under S-8, but with
different TCDD action levels.

     The crystalline TCB and associated TCB spill-related soils
exceeding the action level  of  500 ppm would be excavated and
transported off-site for incineration at a RCRA permitted
facility.  Following treatment of the TCB and  associated soils,
the residuals would be  disposed  of by the off-site  treatment
facility.
                                100

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COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:                     $6,720,000
     Operation and Maintenance:                 $19,500
     Total Present Worth:                    $7,000,000 (rounded)

     Time of Implementation:                    2 years

Alternative 8-8, Option A

DESCRIPTION

     Alternative S-8A provides for the same remedial actions for
the OU2 surface soils as under S-8, except with different action
levels for TCDD.  Bagged soils from contiguous residential areas
and crystalline TCB and TCB spill-related soils would addressed
in the same manner as that described for Alternative Ł-8.
Surface soils with TCDD concentrations above 20 ppb would be
excavated and placed into the on-site CCU.


COST AND TIME OF IMPLEMENTATION

     Total Capital Cost:                     $8,220,000
     Operation and Maintenance:                 $19,500
     Total Present Worth:                    $8,500,000 (rounded)

     Time of Implementation:                    2 years
UNDERGROUND UTILITIES

     Following is a summary of the underground utilities
alternatives presented in the FS.  A more detailed description of
the alternatives can be found in Lhe OU? FS report itself.

     Table 29 presents a summary of the underground utilities
alternatives.

Alternative D-l     No Action

DESCRIPTION

     The no action alternative for underground structures would
involve no additional measures employed to address those  items.
The underground utilities would  remain buried with their  contents
in place.  Access to the site would be prohibited by  the  existing
site fence so that public access would be passively restricted.
Specific institutional controls, maintenance, or monitoring would
not be implemented, except  for those  that would  be performed in


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                                                                                  T»ble 29
                                                      SUMMARY OF THE UNDERGROUND UTILITIES ALTERNATIVES
M
ho
                                                               Chemical sewer,
                                                                Underground
                                                                storage tanks
NOTES:
         1 Aqueous phase treatment at oolite treatment plant.

         1 Solid phase treatment will be selected with soils alternative.
Hydroblast/
Scarification

Foundations
and curbs
Foundations
and curbs
Surface Seal


Foundations
aud curbs with
persistent stains
Aqueous Phase
Treatment1

Rinse materials
from flush,
hydroblast
Rinse materials
from flush,
hydroblast
Solid Phase
Treatment2

Recovered solids
from flush,
scarification, and/
or hydroblast
Recovered solids
from flush,
scarification, and/
or hydroblast

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 accordance with the monitoring and maintenance plan set out in
 the  1984  Court Order.

      Implementing  no remedial activities for the OU2 underground
 utilities and foundations at the site allows the existing
 contaminant  sources to remain in place.  The potential for
 exposure  to  contaminants is not reduced in this alternative.

      The  Superfund program reqri-es that a no-action alternative
 be considered at every site as a basis of comparison when
 evaluating other alternatives.  This alternative would not
 decrease  the toxicity, mobility, or volume of contaminants or
 reduce public health or environmental risks.  Also, this
 alternative would  not comply with State and Federal environmental
 regulations, and therefore, it is not favored by EPA.

 COST AND  TIME OF IMPLEMENTATION

     Capital Cost:                           $0
     Operation and Maintenance:               $0
     Total Cost:                              $0

     Time of Implementation:                  0 years

Alternative U-2     Equipment Plugging and Cleaning

DESCRIPTION

     Under this alternative,  corrective measures would be
 implemented to reduce the risk associated with the underground
 structures.   The chemical sewer would be hydraulically flushed to
remove solids from the line.   After flushing,  the access to the
sewer would be restricted by installing plugs at all available
access locations.  In conjunction with line plugging, subsurface
cut-off barriers would be installed across the line and bedding
 cross-section.  These cut-off barriers would be constructed of
materials such as  clay, membrane sheeting, or other low
permeability material.  The purpose of these barriers is to
 eliminate potential preferential contaminant migration pathways.
 They would be located in the field at points where plugging is
 conducted or where migration may occur off-site.  Any excess
 contaminated soil  from the excavation process would be handled  in
 accordance with the soil alternative.

     The  foundations and curbs would be cleaned by hydroblasting
 using high pressure, low volume water.  In areas with persistent
 staining, surface  scoring  (such as scarification) will be used  to
 remove visible contamination from the exposed  foundations and
 curbs.  Water generated from the sewer flushing and  concrete
 hydroblasting would be treated  in the on-site  wastewater
 treatment plant.   Solids generated from flushing,  hydroblasting,


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and scarification would be handled in accordance with the
selected alternative for soils.

COST AND TIME OF IMPLEMENTATION

     Capital Cost:                           $1,229,000
     Operation and Maintenance:                      $0
     Total Cost:                             $1,229,000 (rounded)

     Time of Implementation:                  1.5 years


Alternative U-3     Equipment Plugging, Cleaning, and Sealing

DESCRIPTION

     This alternative is similar to Alternative U-2, with the
following additions.  After flushing, the sewer would be filled
with grout to improve the structural integrity of the line and
prevent migration of contaminants through the pipe.  In addition,
a surface sealant would be -pplied to foundations and curbs in
areas of persistent staining, i.e..  visible staining that is not
removed by scarification.

COST AND TIME OF IMPLEMENTATION

     Capital Cost:                           $1,359,000
     Operation and Maintenance:                      $0
     Total Cost:                             $1,359,000 (rounded)

     Time of Implementation:                  1.5 years

7.2  ARAR'B

     In conducting a remedial action, EPA is required to attain a
degree of cleanup for s. given site that assures protection of
human health and the environment.  "Applicable or relevant and
appropriate requirements" (ARAR's) are the federal, state, or
local requirements that ensure such a cleanup standard.   (See
CERCLA Section 121(d), 42 U.S.C. S 9621(d), and NCP Section
300.410(g), 40 CFR S 300.410(g).)  Applicable requirements are
those standards, requirements, criteria, or limitations
promulgated under federal environmental, state environmental, or
facility siting laws that specifically address a hazardous
substance, pollutant, contaminant, remedial action, location, or
other circumstance found at  a  CERCLA site.

     Relevant and appropriate  requirements are those  standards,
requirements, criteria, or  limitations promulgated under  federal
environmental,  state environmental,  or facility  siting laws that,
while not  "applicable" to hazardous  substances,  pollutants,
contaminants, remedial actions,  locations, or other circumstances

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 at  a  CERCLA site,  address  problems  or  situations  so that their
 use may  be  suited  to  the particular site.   Factors that may be
 considered  in  making  this  determination, when the factors are
 pertinent,  are discussed at NCP  Section  300.440(g)(2), 40 CFR
 S 300.400(g)(2).   They  include,  among  other considerations,
 examination of:  The  purpose  of  the requirement and the purpose
 of  the CERCLA  action; the  actions or activities regulated by the
 requirement and the remedial  action contemplated  at the site; and
 the potential  use  of  resources affected  by  the requirement and
 the use  or  potential  use of the  affected resource at the CERCLA
 site.

     ARAR's  are divided into  chemical-specific, location-
 specific, and  action-specific requirements.  Chemical-specific
 requirements govern the release  to  the environment of materials
 possessing certain chemical or physical characteristics or
 containing specific chemical  compounds.  Chemical-specific ARAR's
 are numerical  standards.   These values establish the acceptable
 amount or concentration of a  chemical that may be found in,  or
 discharged to, the ambient environment.

     Location-specific ARAR's relate to the geographic or
physical position of the site, rather than to the nature of site
contaminants.  These ARAR's place restrictions on the
 concentration of hazardous substances or the conduct of cleanup
 activities due to the site's  location in the environment (i.e. .  a
 site located in a flood plain).

     Action-specific ARAR's are usually technology- or activity-
based requirements, or are limitations on actions taken with
respect to hazardous substances.   A particular remedial activity
will trigger an action-specific ARAR.  Action-specific ARAR's
dictate how the selected remedy must be imple  r.ted.

     Only the  substantive portions  of requirements are ARAR's.
Administrative requirements are  not ARAR's and, thus, do not
 apply to actions conducted entirely on-site.  Administrative
 requirements are those that are  non-substantive requirements that
 involve such actions as consultation,  issuance of permits,
 documentation, reporting, record keeping, and enforcement.  The
 CERCLA program has its own set of administrative  procedures that
 assure proper  implementation  of  CERCLA because the application of
 additional or  conflicting administrative requirements could
 result in delay or confusion.  Provisions of statutes or
 regulations  that contain general goals that merely express
 legislative  intent about desired outcomes or conditions, but are
 non-binding, are not  ARAR's.

     State  standards  that  are identified in a timely  manner by
 the state in which a  Superfund site is located and are more
 stringent than federal  requirements may be  applicable or  relevant
 and appropriate.   To  be an ARAR, a  state standard must be

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 "promulgated,"  which means that the  standards  are  of  general
 applicability,  are legally enforceable,  and  have been equally
 applied.

     Additional standards  may  be identified  as "to be considered"
 (TBC).  The  TBC category consists of advisories, criteria,  or
 guidance which  was developed by EPA,  other federal agencies,
 states, or local agencies  that may be useful in developing  CERCLA
 remedies.  These may be considered as appropriate  in  sele^^g
 and developing  cleanup actions.

     The potential ARAR's  for  CU2  media  are  listed in Table 30.
 These potential ARAR's were identified based on site-specific
 conditions and  are described in  more  detail  in  the remainder of
 this section.

     In identifying ARAR's for OU2,  it is important to recognize
 that the Vertac site has three existing  burial  areas  that are
 closed under a  1984  Court Order.   In  that Order, dated July 18,
 1984, in the matter styled U.S.  v. Vertac Chemical Corporation
 and Hercules/ Inc..  E.D. Ar., Western Division, No. LR-C-80-109,
Judge Henry Woods  concluded that the  Vertac  Plan,  which EPA
opposed, but which the State of Arkansas supported, was superior
to an alternative  plan submitted by EPA.  Specifically, the
Vertac plan allowed  the burial in the North  Burial Area of
barrelled waste  containing up to 100  ppm dioxin and allowed the
burial in that  location of chlorinated phenols, anisoles,
chlorinated benzenes, 2,4-D, 2,4,5-T, and the burial  of aldrin,
dieldrin and DDT in  the Reasor-Hill Burial Area.   In  addition,
the Court in its Order concluded that the dioxin-containing
barrels buried  in  the North Burial Area do not pose a serious
danger of moving off-site underground.   See  Order  of  July 18,
 1984, at page 4.   Therefore, pursuant to a final order of the
Court, the containment by burial of dioxin wastes  i*»
concentrations  up  to 100 ppm do  not constitute  a principal threat
to the public health or the enviiunmenc,

Table 30.  Potential ARAR's for  the Vertac Site, Jacksonville,
Arkansas

 Chemical-Specific

     •    Resource Conservation and  Recovery Act (RCRA),  42
          U.S.C.  S 6901 et  seq.
     •    Clean Water Act  (CWA),  33  U.S.C. S 1251  et  sea.
     •    Safe  Drinking Water  Act (SDWA), 42 U.S.C. S 300f  et
          seq.
     •    Clean Air Act  (CAA),  42 U.S.C. S 7401 fit sea.
     •    Arkansas Water and Air Pollution Control Act,  ACA 8-4-
          101 - 106 and 8-4-201 - 229,  and 8-4-301 -  313
     •    Arkansas Non-Criteria Air  Pollutants Control Strategy
                                106

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Table  30 - Continued.

     •    Arkansas  State Ground Water Quality Protection  Strategy
     •    State  Implementation Plan  for Air Pollution Control,
          ADPC&E Reg. No.  19
     •    Water  Quality Standards for Surface Waters of the State
          of Arkansas, ADPC&E Reg. No. 2
     •    State  Administration of the National Pollutant
          Discharge Elimination System, ADPC&E Reg. No. 6
     •    Hazardous Waste  Management, ADPC&E Reg. No. 23
     •    Arkansas  Air Pollution Control Code (Minor Source,
          ADPC&E Reg. No.  18), (Operating Air Permit Program,
          ADPC&E Reg. No.  26)

Location-Specific

     •    Resource  Conservation and Recovery Act  (RCRA), 42
          U.S.C. S  6901 gt seq.
     •    Arkansas  Solid Waste Management Code,  ADPC&E Reg.
          No. 22
     •    State  Administration of the National Pollutant
          Discharge Elimination System, ADPC&E Reg. No. 6
     •    Hazardous Waste Management (Arkansas), ADPC&E Reg.
          No. 23
     •    Arkansas Air Pollution Control Code (Minor Source,
          ADPC&E Reg. No.  18),  (Operating Air Permit Program,
          ADPC&E Reg. No.  26)

Action—Specific

     •    Resource Conservation and Recovery Act  (RCRA), 42
          U.S.C. S  6901 et seq.
     •    Clean  Water Act  (CWA),  33 U.S.C. S 1251 et sea.
     •    Safe Drinking Water Act (SDWA), 42 U.S.C. S 300f et
          seq.
     *    Clean  Air Act (CAA), 42 U.S.C. S 7401 eŁ sea.
     •    Arkansas  Solid Waste Management Code, ADPC&E Reg.
          No. 22
     •    state  Implementation Plan  for Air Pollution Control,
          ADPC&E Reg. No.  19

7.2.1  Federal ARAR's

Resource Conservation and  Recovery Act  (RCRA)

     The Resource Conservation and Recovery Act  (RCRA),  42 USC §
6901 et seq.):

•    RCRA Subtitle  C established  a comprehensive regulatory
     program to  control  and manage hazardous  waste from the time
     of generation  to disposal.


                                107

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•    Under RCRA  Subtitle D, EPA promulgated regulations
     containing  guidelines to assist in the development and
     implementation of state non-hazardous solid waste management
     plans.

     RCRA requirements may be ARAR's because some materials at
the Vertac site  are solid wastes and also may be considered RCRA
hazardous wastes.  In general, RCRA regulations apply to the
management of RCRA hazardous wastes and RCRA waste management
facilities.  Regulations promulgated under RCRA generally provide
the basis for management of hazardous waste and establish
technology-based requirements for hazardous waste facilities.
xiCRA facility design standards may also be consulted if
considered relevant and appropriate for wastes other than RCRA
hazardous wastes containing significant concentrations of
hazardous constituents.

Cheaical-Specific Requirements

Hazardous Waste Identification

     The regulations governing the identification and
classification of RCRA hazardous wastes are found at 40 CFR Part
261.   The two basic classifications of RCRA hazardous waste are:

•     Characteristic hazardous wastes (defined at Subpart C of 40
     CFR Part 261),  which involve evaluation of the following
     general waste characteristics:

          Ignitability (D001 waste)
          Corrosivity (D002 waste)
          Reactivity (D003  waste)
          Toxicity (D004 -  D043 wastes) due to specific chemical-
          specific compounds.

•     Listed hazardous wastes (defined at Subpart D of 40 CFR Part
     261),  which involve specific identification of the following
     regulatory listings:

     Hazardous Waste from Non-specific Sources (F- series wastes
     listed at 40 CFR S 261.31).

     Hazardous Waste from Specific Sources (K- series wastes
     listed at 40 CFR S 261.32).

     Commercial Chemical Products  (P- and U- series wastes listed
     at 40 CFR S 261.33).

     Specific tests cited in the regulations are used to
determine if a solid waste also constitutes a RCRA characteristic
hazardous waste.  The maximum concentrations of contaminants
allowed in the leachate of a solid waste before the  solid waste

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 is  considered hazardous  for  the toxicity  characteristic  (TC)  are
 presented  in 40  CFR S  261.24.   Site-related  compounds  for which a
 TC  level has been  identified include:

     Waste Code      Compound Name                    TC  Level
        DO16         2,4-Dichlorophenoxyacetic Acid   10.0 mg/L
        DO41         2,4,5-Trichlorophenol            400 mg/L
        DO42         2,4,6-Trichlorophenol            2.0 mg/L
        DO17         Silvex                           1.0 mg/L

     To determine  if a solid waste is a listed RCRA hazardous
 waste,  it  is  necessary to examine the source of the waste.  At
 the Vertac  site, the manufacture and formulation of insecticides
 and herbicides resulted  in the generation of process wastes
 containing  chlorinated benzenes, chlorinated phenols,
 chlorophenoxy herbicides, and dioxin.  These substances have been
 found in the environmental media (soils, ground water,  and
 surface water) at the site.  A comprehensive listing of
mechanisms that released these substances into these
environmental media is unavailable.  However, material handling
practices,  waste management practices and material releases
during the 45 years of plant operation are the most probable
cause.

     A number of mechanisms could be hypothesized based on the
types of activities performed during site operation,  but most of
the releases cannot be confirmed and likely occurred prior to the
promulgation of RCRA.  An exception is the tetrachlorobenzene
 (TCB)  spill, which resulted from a known release while
transferring tetrachlorobenzene from a rail car to a material
storage tank and occurred after RCRA's promulgation.   Where
spills or releases occurred after the promulgation of RCRA and
it" hazardous waste listings found at 40 CFR P  -t 261,  RCRA
standards are applicable.  Where that is not the case,  RCRA
standards would be either relevant or appropriate.

     Some of the production processes performed, at the Vertac
site would have generated wastes given hazardous waste numbers
F020,  F022, F023, F026, or F027  (40 CFR S 261.31, dioxin-related
hazardous wastes from non-specific sources).  These waste numbers
are referred to in this document as "F-02X" wastes and are
defined at 40 CFR S 261.31.

     Some of the substances  found in the site soils and  other OU2
media may have resulted  from the release of wastes other than the
 F-02X wastes.  These wastes  could potentially be classified as
 follows:

 •    Listed hazardous wastes from specific sources that  are
     related to  2,4-D and 2,4,5-T production are defined at 40
     CFR S  261.32  as K042, K043, and K099 wastes  .


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 •    Wastes  defined  at  40  CFR  S  261.33 as discarded  commercial
     chemical products,  off-specification species, container
     residues,  and spill residues thereof.  The hazardous waste
     identification  code U240  (2,4-D salts, and esters) may be
     applicable to some of the OU2 media at the site.

 •    The soils  containing  residues from a rail car spill
     containing still bottoms  from the production of
     chlorobenzenes  (called throughout this FS as the
     "tetrachlorobenzene spill soils") may be listed as a K085
     specific source listed hazardous waste.  K085 listed
     hazardous  wastes are  identified at 40 CFR S 261.32 as
     distillation or fractionation column bottoms from the
     production of chlorobenzenes.

     Historically, some  chlorobenzene still bottoms were
     purchased  from  an off-site facility (generated at the off-
     site facility during the  production of dichlorobenzene)  and
     were transported via rail car to the site.  The stixl
     bottoms contained high levels of tetrachlorobenzene and were
     dechlorinated on-site as part of the 2,4,5-trichlorophenol
     manufacturing process.  Prior to use on-site,  a hose leading
     from a rail car containing the still bottoms to a storage
     tank ruptured spilling the chlorobenzenes onto the ground
     surface along the rail spur immediately north of the central
     process area.  These soils are included as part of the OU2
     remedial action and may require management as a K085 waste.

•    Residues from the treatment of a listed RCRA hazardous waste
     are themselves considered RCRA hazardous wastes unless
     delisted.   Residues resulting from the incineration or
     thermal treatment of the F-02X materials would be considered
     F028 wastes per 40 CFR §  261.31.

     The regulations pertaining to the dioxin-containing F-listed
wastes are more stringent than for the other listed wastes.  For
example, 99.9999 percent (six  9's) destruction removal efficiency
(ORE) is required for incineration of these dioxin-containing
wastes, while only 99.99 percent (four 9's) ORE is required for
most other wastes.   Regulatory requirements for the land disposal
of the F-02X are also more stringent than for other wastes.
Therefore, complying with the  regulations applicable to the F-
listed wastes ensures compliance with less stringent regulations
applicable to non-F02X  listed  RCRA wastes.

Mixture Rul«/Contain«d-In  Policy

     The "mixture rule"  found  at 40 CFR S 261.3 states that a
mixture of a solid waste and a listed RCRA hazardous waste may be
considered a RCRA hazardous waste.  This may be applicable to the
solids in the underground  piping  if the contents are determined
to be mixture of a solid waste and a listed RCRA hazardous waste.

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 In  the  "contained  in" policy, the EPA has further expanded the
 mixture rule to  include environmental media  (not considered a
 "solid  waste" under RCRA) mixed with a  listed RCRA hazardous
 waste.  In this  policy, EPA has stated  that  the mixture of a
 listed  RCRA hazardous waste and an environmental medium shall be
 a listed RCRA hazardous waste until decontaminated and should be
 managed as a hazardous waste for as long as  the medium contains
 the listed waste.  As a result of this  policy, on-site soils
 containing listed  RCRA hazardous waste  may be required to be
 managed as a listed RCRA hazardous waste.  See 40 CFR §§
 261.3(c)(l) and  261.3(d)(2).  Also see  the discussion in the
 preamble to the  proposed NCP revisions, Federal Register volume
 53, page 51444 (December 21, 1988).

 RCRA Maximal Contaminant Levels (MCL's)

     As part of  the ground water protection  requirements for RCRA
 treatment, storage, or disposal facilities (TSD's),  EPA has
 promulgated at 40 CFR S 264.94 maximum  concentrations of
 constituents in ground water (RCRA MCL's).   The constituents,  and
 their associated concentrations in ground water, addressed by
 this requirement are presented at 40 CFR S 264.94.   The standards
 for site-related compounds are as follows:

     •    2,4-D      0.1 mg/L
     •    Silvex     0.01 mg/L

     These ground water protection standards are equal to MCL's
 established in the National Primary Drinking Water Standards
promulgated pursuant to the Safe Drinking Water Act (SDWA) ,  42
U.S.C. S 300f et sea.   The basic jurisdictional prerequisites for
RCRA MCL's are part of the RCRA ground water monitoring and
 response requirements,  which apply to RCRA-regulated units
 subject to permitting (e.g., landfills, surface impoundments,
waste piles,  and land treatment units)   that  received RCRA
 hazardous waste  after July 26, 1982.  Therefore, RCRA MCL's would
 be considered as part of any long-term  monitoring program for
most on-site remedial measures.  EPA will address the long-term
 monitoring of ground water in the ROD for OU3, which will focus
 on ground water  issues and which EPA has yet to issue.

 RCRA Location-Specific Requirements

     Location-specific ARAR's within RCRA are location standards
 detailed at 40 CFR S 264.18 that are potentially applicable to
 the siting of a  new on-site TSD unit managing RCRA hazardous
 waste as part of a remedial alternative.

     These location standards are specified  and addressed as
 follows:
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 •     Seismic  considerations  restricting TSD  facilities within  200
      feet  of  a  fault  that has had a displacement within Holocene
      time.  Because the Vertac  site is not located  in
      jurisdictions listed in Appendix VI of  40  CFR  Part 264, such
      an  on-site facility would  be in compliance with this
      requirement as per 40 CFR  § 270.14(b)(11).

 •     Flood plain considerations requiring TSD facilities located
      within a 100-year flood plain to be designed,  constructed,
      operated,  and maintained to prevent washout (the movement of
      hazardous  waste  from the active portion of the facility as a
      result of  flooding) .  Par*: of tho site contains portions of
      the 100-year flood plain.  Approximately 150 feet to the
      east  and west of Rocky  Branch Creek are included within the
      100-year flood plain.

 •     Salt dome  formationsf salt bed formations, underground mines
      and caves  are locations where placement of non-containerized
      or bulk  liquid hazardous waste is prohibited.   This
      requirement is not applicable to the Vertac site because
      these features are not  located within the area of the site.

RCRA Action-Specific ARAR's

     Action-specific ARAR's are usually technology or activity-
based requirements or limitations on actions taken with respect
to hazardous wastes.   These requirements may be triggered by the
particular remedial action that is selected to accomplish the
selected alternative.   Because there is more than one alternative
action for the OU2 media at the site,  many different requirements
may be applicable.

General TSD Facility Requirements

      General TSD facility requirements under RCRA apply to those
facilities that treat, store, or dispose RCRA hazardous wastes.
The requirements that could potentially be ARAR's at the site
include:

•     General  facility standards (40 CFR Part 264, Subpart B)
      including  those  for waste  analysis.

•     Preparedness and prevention standards (40  CFR  Part 264,
      Subpart  C)  addressing facility design and  operation and
      required equipment.

 •     Contingency plan and emergency procedures  (40  CFR Part 264,
      Subpart  D).

 •     Manifest system  recordkeeping and reporting  (40  CFR  Part
      264,  Subpart E)  to continuously track off-site hazardous
      waste transport.

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 •     Releases  from solid waste management units  (40 CFR Part 264,
      Subpart F)  for new landfills,  land treatment, and waste pile
      units.  This  includes provision for ground  water monitoring
      programs.

 •     Closure and post-closure requirements  (40 CFR Part 264,
      Subpart G)  requiring removal of waste  and residuals to an
      extent that controls, minimizes, or eliminates post-closure
      release of  hazardous constituents.

 •     Use and management of containers (40 CFR Part 264, Subpart
      I) which provides standards for the condition of containers,
      waste compatibility, inspections, LBorage building design
      and construction, and closure.

 •     Landfills (40  CFR Part 264, Subpart N).

 •     Incinerators  (40 CFR Part 264, Subpart 0).

Land Disposal Restrictions

     The land ban, promulgated pursuant to RCRA Section 3004,  42
U.S.C. § 6924,  on 7 November 1986 and codified at 40 CFR Part
268, Subparts A,  C, and D,  stipulates that no hazardous wastes
 (as defined at 40 CFR S 261.31)  may be land disposed unless
treated.  RCRA requires that the treatment of wastes that are
subject to the ban on land disposal attain levels achievable by
the best demonstrated available technology  (BOAT).  BOAT requires
that a treated F-02X material have less than 1 ppb TCDD,  as
measured by the Toxicity Characteristic Leaching Procedure (TCLP)
found at 40 CFR Part 261,  App. II, prior to disposal in a RCRA-
permitted landfill.

     The land disposal restrictions (LDR's) also apply to the
storage of certain hazardous wastes on-site.  These restrictions
prohibit the on-site storage of "bannad" wastes  for longer than l
year unless the owner/operator can prove that the extended
storage is solely for the purpose of accumulating enough waste
for proper treatment. Thus, all materials potentially subject to
LDR's that have been stored on-site and whose disposition is the
subject of this ROD have been accumulated in such a manner.

Conso1idation

      As long as  contaminated material remains within a CERCLA
Area  of Contamination  (AOC), EPA generally  does  not consider
placement to have  occurred.  See  55 Fed. Reg.  8760  (March  6,
 1990).  The Agency has codified that principal in the RCRA
 corrective action  regulations, such as the  Corrective Action
 Management Unit  Rule,  58 Fed. Reg.  8658  (Feb.  16,  1993), which
 generally may  permit movement of  contaminated material outside an
 AOC for on-site  handling or  treatment without triggering

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placement  and  the  associated LDR treatment and disposal
requirements.

      For LDR's to  be  applicable requirements, EPA must first
determine  whether  consolidation activities considered or
contemplated at the Vertac  site constitute placement.   To assist
in defining when placement  does and does not occur for CERCLA
actions involving  on-site disposal of wastes, EPA uses the
concept of AOC's,  which may be viewed as equivalent to RCP»
units, for the purposes of  LDR applicability determinations.  An
AOC  is delineated  by  the areal extent of contiguous
contamination.   Such contamination must be continuous, but may
contain varying types and concentrations of ^azardous substances.
Depending  upon site characteristics, one or more AOC's may be
delineated.

      Placement does not occur when wastes are consolidated within
a land-based unit, when they are treated in situ, when they are
left  in place,  or when they are moved within an AOC.  See 55 FR
8666, 8758-8760  (March 8, 1990), and "Determining When Land
Disposal Restrictions (LDR's)  Are Applicable to CERCLA Response
Actions," OSWER Directive 9347.3-O5FS (July 1989).  Also see 61
FR 18804-18805  (April 29, 1996).  Specifically,  placement does
not occur when the wastes are consolidated within the AOC.

     EPA considers the entire landmass of the Vertac site to be
contaminated due to the fact that TCDD levels in the soils found
on-site and on contiguous contaminated off-site areas exceed the
background TCDD level found in Jacksonville of 0.3 ppb or less.
Therefore,  all consolidation actions contemplated in this ROD
that will apply to excavated on-site soils and debris,  or to
soils and debris removed from areas contiguous to the site, are
within the AOC  for purposes of determining the applicability of
LDR's due to the fact that TCDD concentrations withi^ the AOC and
contiguous contaminated areas exceed background TCDD
concentrations by substantial orders of magnitude.  Thus, during
the on-site consolidation activities, materialr will be
consolidated within the AOC, and therefore, the land disposal
restrictions are not  applicable.

     However,  if the  materials are treated on-site within the AOC
in a manner that would constitute "treatment" as that term is
defined at RCRA Section 1004(34), 42 U.S.C. S 6903(34), and then
redeposited within the AOC  such as in the consolidation unit,
then  placement has occurred and the land disposal restrictions
apply, unless  a treatability variance under 40 CFR S 268.44 is
obtained,  or unless the ARAR is waived under CERCLA Section
121(d)(4)(A),  42 U.S.C. S 9621(d)(4)(A), and  NCP Section
300.430(f)(1)(ii)(C)(l)f 40 CFR S 300.430(f)(1)(ii)(C)(1).

      On July 18,  1996, the  EPA  Region 6  executed an Amended Non-
Time  Critical  Action  Memorandum that, among other things,  granted

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 a  treatability  variance  pursuant to 40 CFR S 268.44, of the  1 ppb
 LDR  treatment standard for  dioxin-contaminated wastes set out at
 40 CFR  §  268.31,  to  allow the on-site disposal of treatability
 residues  from the on-site incineration of TCDD-contaminated
 Vertac  wastes.  That treatability variance allows the on-site
 disposal  of Vertac site-related dioxin-contaminated materials,
 such as some of the  incinerator ash and possibly some shredded
 pallets and incinerator  salt residuals, that exceed the 1 ppb LDR
 treatment standard but that fall below the 5 ppb alternative
 treatment standard selected in the treatability variance section
 of the  Action Memorandum.

      Therefore, should placement occur with respect to Vertac
 TCDD wastes within the AOC, the treated materials cannot exceed
 the  5 ppb TCDD  alternate LDR treatment standard selected in the
 July 18,  1996,  Action Memorandum.  In addition, EPA has
 established LDR treatment standards for most of the hazardous
wastes  associated  with the Vertac site, but,  as discussed above,
they will  not be applicable where consolidation within the CCU
occurs  since placement will not have occurred.

     Finally,  substantive, versus procedural, minimum technology
requirements (MTR's)  are applicable for the CCU to be constructed
within an AOC, due to the fact that the CCU will be constructed
on-site, within the AOC.

Incinerators

     Incineration of a RCRA hazardous waste is regulated under 40
CFR Part 264,  Subpart O.   These regulations include provisions
for:
•    Conduct of a trial burn (40 CFR SS 270.19(b)  and
270.62(b)(6^.

•    Incinerator start up/shut down requirements (40 CFR S
264.345(d).

•    Waste feed analysis (40 CFR SS 264.341 and 270.62(b)(2).

 •    Operating  requirements (40 CFR S 264.345).  This includes a
     control of fugitive emissions either by keeping the
     combustion zone totally sealed or maintaining a combustion
      zone  pressure lower than atmospheric pressure.  In addition,
      an automatic  cutoff system must be provided to stop the
     waste feed when operating conditions deviate from design
      conditions.

 •    Monitoring and  inspections  (40 CFR S 264.347(a)).  This
      includes monitoring of the  following operating parameters:

      -  Combustion temperature.
      -  Waste feed rate.

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      -  Combustion gas  velocity.
      -  Carbon  monoxide (CO)  emissions.

 •     Closure with disposal  of hazardous waste and residues,
      including ash,  scrubber water, and scrubber sludge  (40  CFR  §
      264.351).

 •     Compliance with additional general TSD facility
      requirements.

      In addition,  the  regulacions set the following performance
 standards for  incineration at 40 CFR § 264.343 that require that
 the incinerator:

 •    Achieves a destruction  and removal efficiency (ORE) of
     99.9999 percent (six 9's) for each principal organic
     hazardous constituent  (POHC)  in the waste feed for F-02X
     wastes.  A ORE of 99.99 percent (four 9's)  is required for
     non-F-02X wastes.  For F-02X wastes, the ORE must be
     demonstrated on POHC's that are more difficult to incinerate
     than tetra-,  penta-,   id hexachlorodibenzo-p-dioxins and
     dibenzofurans.  In addition,  the owner or operator of the
     incinerator must notify the Regional Administrator of his
     intent to incinerate F-02X wastes.

•    Reduces hydrogen chloride (HCl)  emissions to 1.8 kg/hr or 1
     percent of the HCl in the stack gas before entering any
     pollution control device.

•    Does not release particulate matter in excess of 180 mg/dscm
     (milligrams per dry standard cubic meter),  corrected for the
     amount of oxygen in the stack gas.

     The ability to meet these performance standards must be
demonstrated during the trial burn period.

     Furthermore,  as discussed above,  monitoring of various
parameters during operation of the incinerator is required per 40
CFR S 264.347. These operating parameters include:

•    Combustion temperature

•    Waste feed rate

•    An indicator of combustion gas velocity

•    Carbon monoxide emissions

     Finally,  fugitive emissions must be  controlled  (40  CFR
364.345) either by:

 •    Keeping the  combustion  zone totally  sealed.

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 •     Or  maintaining a  combustion  zone pressure  lower than
      atmospheric  pressure.

      The EPA has  Standards  for Owners and Operators of Hazardous
 Waste Incinerators  (40 CFR  Parts  260, 261, 264, and 270).  The
 standards establish risk-based emission limits  for individual
 toxic metals (Appendix VIII of 40 CFR Part 261).  The EPA also
 regulates hydrochloric acid (HC1) emissions using the same risk-
 based approach proposed for metals.  The limits are back -
 calculated from ambient levels that the EPA believes pose an
 acceptable health risk.  To simplify this process, the EPA has
 developed conservative screeniry limits based on terrain and
 effective stack height.  If the screening limits are not
 exceeded,  the Agency has determined that emissions do not pose
 unacceptable risk.   If the  screening limits are exceeded,
 however,  site-specific dispersion analysis is required to
 demonstrate  that  emissions  will not result in an excecdance of
 acceptable ambient  levels.  The risk-based controls are applied
 on a  case-by-case basis to  ensure that the existing technology-
 based standard is protective.

     Existing regulations control organic emissions by the ORE
 standard  in  40 CFR  S 264.343(a).   This standard limits stack
 emissions of POHC's to  0.0001 percent (for dioxin-containing
waste) of the quantity of the POHC fed into the incinerator.   The
 standard considers  a POHC to be destroyed (or removed in ash or
 scrubber water)  if  it  is not present in the stack emissions.

     Given that stack gas carbon monoxide (CO)  is a conventional
 indicator of combustion efficiency and a conservative indicator
of combustion upsets (i.e.,  poor combustion conditions),
emissions to a 3e minirois level (100 ppmv - parts per million by
volume) ensures high combustion efficiency an^ "'.ow unburned
hydrocarbon  emissions.  The owner or operator would be required
 to demonstrate that higher  CO levels would not result in high
hydrocarbon  emissions,  in cases where che CO limit is exceeded.

 Delisting

      If residues  from  treatment are delisted, they are no longer
 considered to constitute RCRA hazardous wastes, and the wastes
 could be  placed in  any landfill permitted to receive non-RCRA
 hazardous solid waste.  Delisting of the material would  involve
 petitioning  the EPA Regional Administrator of Region 6 to remove
 the site-specific waste from the  list of RCRA hazardous  wastes
 and to consider it  nonhazardous.  The petition  must state the
 need  and justification for  the delisting, and it must include
 supportive documentation that demonstrates to the Administrator
 why the  material  does  not meet any  of the criteria under which
 the original waste  was listed.  A rotary kiln was used to
 incinerate wastes from the  Vertac site  at the U.S. EPA Combustion
 Research Facility (CRF) in  Jefferson, Arkansas  as  a pilot

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project.   Scrubber  brines  and  ash generated  in that pilot burn
have  been  delisted  by  the  U.S.  EPA  (Federal  Register Vol. 54, No.
71, 14 April  1989).  A similar delisting procedure would be
required for  any  F-Listed  materials treated  at the site prior to
disposal in a landfill not permitted to accept these F-listed
wastes.

Hazardous  Waste Landfills

      The technical  requirements for an on-site consolidation unit
may,  but are  not  required  to,  be considered  as relevant and
appropriate certain design guidance (such as requirements for
such  things as covers/caps, drainage, liners, stability)
pertaining to RCRA-permitted facilities.  RCRA-specific
requirements  for  a  hazardous waste landfill  are found at 40 CFR §
264.300 (Subpart  N), which could be considered for a
consolidation unit.  These requirements would be applicable to an
on-site containment unit if residues from treatment were to be
put into the  unit without  delisting.  40 CFR S 264.301 states
that  a RCRA landfill must  have  two or more liners that are
designed,   constructed, and installed to prevent migration of
wastes out of the landfill to the adjacent soil or subsurface
soil or ground water during the active life of the landfill.
Other liner system requirements include:

•    Construction with materials that have appropriate chemical
     properties and sufficient strength to prevent failure.

•    Placement upon a base capable of providing support to the
      liner.

•    Installation to cover all earth likely to be in contact with
     the waste or leachate.

     Furthermore,  leachate collection systems are required above
and between the liners that are designed, constructed,
maintained, and operated to collect and remove any leachate from
the landfill.  For a RCRA  landfill, the leachate collection and
removal systems must be:

•     Chemically resistant  to the waste managed or leachate
      expected in  the landfill.

•     Of sufficient  strength and thickness to prevent collapse
      under the pressure exerted by the overlying waste.

•     Designed and operated to  prevent clogging through  the
      scheduled closure of  the  landfill.

      Furthermore, RCRA presents specific requirements  for F-02X
wastes.  In order to place F-02X wastes  into a  landfill, the
landfill must be  operated  in accordance with a management plan

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 for  these  wastes that is approved by the  Regional Administrator
 (40  CFR S  264.317).   Approval  of  the management plan would be
 based  on the  following factors:

 •    The volume,  physical,  and chemical characteristics of the
     waste, including migration potential.

 •    The attenuative  properties of the underlying and surrounding
     soils.

 •    The effectiveness of additional treatment, design, or
     monitoring  requirements.

     Finally, RCRA also presents monitoring, inspection,
 surveying, record-keeping,  closure,  and post-closure care
 requirements  (40  CFR  SS 264.303 -  264.310), and general facility
 management requirements.

     A RCRA-equivalent consolidation/containment unit (CCU)  will
 be constructed on-site as part of  the remediation for OU1 for on-
 site disposal of demolition debris.  The CCU will be designed to
meet substantive RCRA  requirements,  and it will be designed to
 contain adequate capacity to hold whatever volumes of
contaminated soil and  debris this ROD may propose to consolidate
within that CCU, which will lie within the AOC.

Treatment Standards for Hazardous Debris

     Treatment of hazardous debris is required if the debris is
to be land disposed,  assuming that the debris does not remain
within the CERCLA area  of contamination (AOC).   As discussed
earlier, as long as contaminated material remains within a CERCLA
Area of Contamination  (AOC), EPA generally does not consider
placement to have occurred.   See 55  Fed. Reg. 8760 (March 6,
 1990).   RCRA corrective action regulations, such as the
Corrective Action Management Unit Rule, 58 Fed. Reg. 8658 (Feb.
 16, 1993),  may permit  movement of  contaminated material outside
an AOC for on-site handling or treatment without triggering
placement and the associated LDR treatment and disposal
 requirements.   However, where  "placement" does occur, debris must
 be treated using the technology or technologies identified in
 Table 1  of 40 CFR S 268.45, or the waste-specific treatment
 standards for the waste contaminating the debris.

     In  addition, 40  CFR S  268.44  allows  EPA to apply alternative
 treatment standards under the  Land Disposal Restrictions  (LDR's)
 found at 40 CFR  Part  268 where best  demonstrated available
 technology  (BOAT) treatment standards are in effect, but  where
 resort to the waste-specific BOAT LDR treatment standard  is  not
 appropriate for  the treatment  of  the waste in  question.   The
 National Contingency  Plan  (NCP),  40  CFR Part 300, has  expressly
 approved, on  a site-by-site basis, the  use of  the LDR

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treatability variance  for  CERCLA response actions  involving
contaminated soil  and  debris.   See preamble to the NCP at pages
8761 and 8762,  55  Fed. Reg.  8761 and 8762, March 8,  1990.

     In general, the treatment  standards for hazardous debris are
not applicable  if  the  OU2  debris (i.e. . manholes,  sumps, sewers,
and foundations) is consolidated and not land disposed.  If this
debris is managed  in place,  the hazardous debris standards may be
relevant and appropriate.

Clean Watar Act  (CWA)

     The Clean Water Act (CWA) , 3J U.S.C. S 1251 et  sea. .
required EPA to establish  regulations to protect the quality of
surface waters across  the  nation.  The CWA may be  applicable to
treatment and discharge of water used as part of a remedial
action where the treatment and  discharge occurs on-site.  For any
off -site discharges, both  procedural and substantive CWA
requirements would apply.  "On-site" discharges should meet
substantive requirements but are exempt from federal, state and
local permitting requireme. s.  See CERCLA Section 121(e)(2),  42
U.S.C.  S 962l(e)(2), and 40 CFR 300.400(e).   A discharge of
CERCLA wastewaters is considered "on-site" if the receiving water
body is in the area of contamination or is in very close
proximity to the site and  is necessary for the implementation of
the response action (even  if the water body flows off-site) .

     Under the CWA, three  interrelated areas were identified for
regulation:

•    Establishment of water quality standards;

•    Establishment of storm water runoff control; and

•    Establishment of effluent  standards (discharge  limitations)
     intended to ensure compliance with applicable water quality
     rtandards .

     Water quality standards represent chemical-specific
requirements, while storm  water runoff controls and  effluent
standards are action-based requirements.  Each is  addressed
separately below.
Chwaical-Spttcif ic

Water Quality Criteria  (WQC)

     CERCLA Section  121(d) (2) (A) ,  42 U.S.C.  S  9621 (d) (2) (A) ,
states that remedial actions  shall attain Federal water quality
criteria where they  are relevant and appropriate under the
circumstances of the release  or threatened release.   Water
quality criteria are non-enforceable guidance  developed under the

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 Clean  Water  Act  (CWA)  Section 304,  33  U.S.C.  S  1314, but are used
 by  the state,  in conjunction with a designated  use  for a stream
 segment,  to  establish  water  quality standards under CWA Section
 303, 33 U.S.C. § 1313.   In determining the  applicability or
 relevance and  appropriateness of water quality  criteria, the most
 important factors to consider are the  designated uses of the
 water  and the  purposes for which the potential  requirements are
 intended.  Water quality criteria have been developed based on:

 •    Protection  of human health.  These levels  have been
     developed based on two  separate potential  exposure pathways.
     The  first criterion is  based solely on consumption of fish,
     while the second  criterion considers both  consumption of
     fish and  consumption of water.

 •    Protection  of aquatic life.  These levels  have been
     developed based on acute toxicity and  chronic  toxicity
     effects to  aquatic organisms.

     Whether a water quality criterion  is appropriate and which
 form of the criterion  is  appropriate depends on the likely
 route(s) and receptors  of exposure.

Action-Specific Requirements

Storm Water Runoff Control

     The EPA has  issued regulations setting forth the NPDES
permit application requirements for discharges of storm water
 from industrial activities (40 CFR 122, 123, and 124).   An NPDES
permit is required for  all discharges of storm water from
 industrial activities as defined in the November 1990
regulations, as amended.  In  states which hav vaen granted NPDES
permitting authority by the  EPA, all NPD^S permits are issued and
 administered by the state regulatory agency.  The ADPC&E has been
granted authority  over  the NPDES program.  The  requirements of
the s^ate NPDES program are  discussed  in Subsection 2.3.3.
However,  for all  on-site discharge activity, only substantive,
versus procedural  (such as obtaining a  permit), is  required.  See
 CERCLA Section 121(e)(2),  42  U.S.C.  S  9621(e)(2).

     As a result of previous on-site remedial actions, the
 central process  area is surrounded  by  a series  of five concrete-
 lined drainage ditches and collection  sumps.  During a storm
 event the drainage ditches divert run-off to  the sumps.  The
 initial sump volume  (first flush) for  each  of the five sumps  is
 diverted  to  the  on-site treatment plant.  Overflow  from the sumps
 currently discharges to Rocky Branch Creek  without  treatment.
 Therefore, after soils remediation  is  complete, Hercules,  Inc.
 will develop a storm water management  plan  called a Storm Water
 Pollution Prevention Plan (SWPPP) to address,  in part,
 elimination  or significant reduction of the sump overflows and

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develop management  controls  for  storm  events.   The  SWPPP will be
developed  in  accordance with criteria  contained in  EPA's Final
National Pollutant  Discharge Elimination  System Storm Water
Multi-Sector  General  Permit  for  Industrial Activities.  (60 FR
50804)

Direct Discharge of Treatment System Effluents

     Direct discharge of wastewaters to a surface water is
governed by tlie NPDES permitting requirements.   40  CFR Parts 122,
125, and 129  as applicable to point source discharges to waters
of the United States, which  reruire:

•    The use  of the Best Available Technology (BAT) economically
     achievable to  control toxic and nonconventional pollutants.


•    Use of best conventional control technology (BCT)  is
     required to control conventional pollutants.  Technology-
     based limitations may be determined on a case-by-case basis.

•    40 CFR S 122.44 and state regulations approved under 40 CFR
     Part 131 require compliance with applicable Federally-
     approved state water quality standards.    These standards
     may be in addition to or more stringent than other Federal
     standards under the CWA.

•    40 CFR S 122.44(e)  requires that discharge limitations must
     be established at more stringent levels than technology-
     based standards for toxic pollutants.

•    40 CFR S 125.100 requires that Best Management Practices
     (BMP)  be developed and implemented to prevent the release of
     toxic constituents to surface waters.

•    40 CFR S 122.41(i)  requires that discharges must be
     monitored to assure compliance.   The discharger will
     monitor the mass of each pollutant, the volume of effluent,
     and the frequency of discharge and other measurements as
     appropriate.

     The direct discharge requirements may be applicable if
waters generated during the  remediation are discharged to Rocky
Branch Creek.  ADPC&E has established discharge limitations which
would apply to the  site wastewaters if they are discharged to
Rocky Branch  Creek.  Water generated during OU2 and as a result
of perpetual  operation and maintenance will need to be treated to
meet applicable water-quality based, effluent discharge limits.
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 The Clean Air Act (CAA),  42  U.8.C.  S 7401 et sea.

      The Clean Air Act (CAA)  and the 1990 CAA Amendments  required
 EPA to  establish regulations to protect  ambient  air  quality.   In
 response to  this mandate,  the EPA directed the following:

 •     Establishment of  National Ambient Air Quality Standards
      (NAAQS).

 •     Establishment of  maximum emission standards as  expressed
      under the National Emission Standards for Hazardous Air
      Pollutants (NESHAP).  These standards apply to  emissions
      from specific sources,  and do not constitute an ARAR for
      activities that are expected to take  place at the Vertac
      site.

 •     Establishment of  maximum emission standards as  expressed
      under the  New Source Performance Standards  (NSPS).

Chemical-specific  Requirements

National Ambient Air Quality  Standards

     National Ambient Air Quality Standards  (NAAQS)   (40 CFR Part
50) have been developed by the EPA for seven classes of
pollutants:  Particulates, sulfur oxides, nitrogen oxides,
hydrocarbons, oxidants (ozone), carbon monoxide,  and lead.  The
NAAQS focus on two  levels of  control:  Primary and secondary.
The primary standards apply exclusively to the protection of
human health, while the secondary standards are set to protect
welfare, including wildlife,  climate, recreation, transportation,
and economic values.  A listing of NAAQS primary and secondary
standards i ; included  in 40 CFR Part 50.   The NAAQS specify
maximum primary and secondary 24 hour concentrations for
particulate matter  in the ambient air.  These ambient sir
concentrations are not designed to apply to specific sources;
rather,  states may promulgate State Implementation Plan (SIP)
emission limits applicable to sources, which will result in
attainment and maintenance of the NAAQS.  While not ARAR's, NAAQS
provide guidance with  respect to  appropriate levels  of
particulate airborne emissions.

      It should  be  noted that  these standards are not emission
 (i.e.. discharge)  standards,  but are standards to be met  for the
 ambient air, after allowing  for mixing of  the particular
 discharge with the ambient air.   NAAQS attainment requirements
 are applicable only to "major sources," which  are pollutant-
 specific,  or sources which emit 10 tons/year of  a single
 regulated  hazardous air pollutant (HAP) or 25  tons/year of  any
 combination of regulated pollutants  (HAP's).   The definition of
 "major sources" is also dependent on the  local attainment
 classification.   Pulaski County,  Arkansas,  is  designated  as an

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ozone maintenance area, and therefore a  "major source" is defined
as any  source with the uncontrolled potential to emit 100
tons/year of volatile organic compounds  (VOC's).

     State Implementation Plans  (SIPs) are developed by
individual states and contain the actual abatement requirements
necessary to achieve compliance with the NAAQS.

     Ambient air monitoring during remediation may be part of the
selected remedial action for OU2.  Perimeter air samplers and
real-time ambient air monitors may be used to monitor ambient air
quality on-site.  Particulates would be the NAAQS contaminant of
greatest concern on-site if soil excavation is required.
Engineering controls would be necessary if particulate
concentrations in ambient air become a concern.  VOC emissions
would be the NAAQS contaminant of concern if incineration were
part of a remedial action.

Action-Specific Requirements

New Source Performance Star'irds (NSPS)

     NSPS regulations found at 40 CFR Part 60 have been
promulgated to cover particulate discharges from a number of
different types of facilities,  including incinerators.
Incineration regulations are listed under 40 CFR Part 60, Subpart
E, Standard of Performance for Incinerators.   The operating
standard found at 40 CFR S 60.52 is that the discharge of
particulate matter shall not exceed 180 mg/dscm (milligrams per
dry standard cubic meter), corrected to 12% C02.   This provision
applies to incinerators with a charging rate exceeding 50 metric
tons per day.  It should be noted that this performance standard
for particulate matter matches that listed under the RCRA
regulations for incinerators found at 40 CFR Parts 264 and 270.

     If the treatment process selected for OU2 has a charging
rate exceeding 50 tons per day, the NSPS may be applicable.
However, the particulate standard stated above should be easily
attained using commercially available air pollution control
equipment.

7.2.2  STATE ARAR'S

Regulation No. 2; Water Quality Standards for Surface Waters

     Pursuant to the Arkansas Water and Air Pollution Control  Act
(AWAPCA), ACA 8-4-101 - 106, 8-4-201 - 229, and 8-4-301  -  313,
and in compliance with the requirements  of the Federal Water
Pollution Control Act, the State of Arkansas has developed water
quality standards for all surface waters,  interstate and
intrastate.  Established water quality standards are based upon
present, future, and potential uses of the surface waters  of  the

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 state  and  criteria  developed  from  statistical evaluations of past
 water  quality  conditions  and  a comprehensive study of  least-
 disturbed,  ecoregion  reference streams.  The standards are
 designed to enhance the quality, value, and beneficial uses of
 the water  resources of the  state;  aid in the prevention, control,
 and abatement  of water pollution;  provide for the protection and
 propagation of fish and wildlife,  and; provide for recreation in
 and on the water.

     General standards for  color,  taste and odor, solids, toxics,
 and oil/grease have been  developed.  In addition, specific
 standards  for  temperature,  turbidity, pH, dissolved oxygen,
 radioactivity,  bacteria,  toxics, nutrients, oil/grease, and
 mineral quality have  been developed depending on the individual
 ecoregions  within the state.  The  site is situated within the
 Arkansas River Valley Ecoregion.

     Water  quality  standards relate to the existing on-site
 treatment plant and its off-site discharges.   As part of OU2,
 the existing treatment plant may be utilized to treat collected
 storm water and wastewaters generated as part of the remediation.
Although the existing treatment plant currently discharges to a
 local Publicly-Owner Treatment Works (POTW), discharge
 limitations for discharge to Rocky Branch Creek have been
proposed by ADPC&E.

Regulation  3; Certification of Wastewater Utilities Personnel

     Operators  in responsible charge of wastewater treatment
 facilities  are required to be licensed and certified by ADPC&E in
order to safeguard the public health and protect the waters of
the state from pollution.   Certification typically includes
training,  classifying, and  licensing of treatm  t plant
operators.

Regulation  6;  State Administration of the National Pollutant
Discharge Elimination System  (NPDES)

     The technical,  versus  procedural, requirements of an NPDES
 permit may  apply if wastewaters generated at the site  are
 directly discharged off-site  into  Rocky Branch Creek.  Further,
 the technical,  versus procedural,  requirements of a storm water
 permit may  apply if storm water discharges associated  with the
 site remedial  activities  that involve disturbing more  than five
 (5) acres  are  discharged  off-site  to Rocky Branch Creek.  An
 individual  NPDES permit may be issued by the ADPC&E, or general
 permit coverage may be obtained under the Department's General
 NPDES Permit No. ARROOAOOO.   Obtaining NPDES coverage  for off-
 site storm water discharges requires  submission  of an  individual
 application, or Notice-of-Intent  (NOI), development  and
 implementation of a Storm Water Pollution Prevention Plan,  and
 possibly storm water  sampling and  monitoring.

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     The existing treatment plant on-site may be used to treat
wastewaters generated  as part of the OU2 remediation.  Currently
this treatment plant discharges to a local POTW in accordance
with a previous permit.  However, as part of the off-site
remedial action, the treated effluent will go to Rocky Branch
Creek.  The system will allow compliance with discharge
limitations which have been proposed to control the discharge to
Rocky Branch Creek.

Regulation 23; Hazardous Waste Management Code

     The Arkansas Hazardous Waste Management Act of 1979 and the
Arkansas Resource Reclamation Act of 1979 are known together as
the Arkansas Hazardous Waste Management Code (amended June 1992),
ADPC&E Reg. No. 23.  This code resembles the federal hazardous
waste management regulations promulgated under RCRA.   The
Arkansas Hazardous Waste Management Code does contain siting
criteria (Section S) for a hazardous waste management facility.
Such a facility may not be sited in the following areas:

•    An active fault zone.

•    A "regulatory floodway" as adopted by communities
     participating in the National Flood Program.

•    A 100-year flood plain.

•    A recharge zone of sole source aquifer designated pursuant
     to the SDWA.

•    Wetlands areas that are inundated or saturated by surface
     water or ground water.

     In addition,  no permit shall be issued for a hazardous waste
landfill facility or surface impoundment if such a facility is
located in the following areas:

•    Areas of high earthquake potential.

•    Areas having a soil that would be classified as vertisol.

•    Areas in which a  stratum of limestone or similar rock of an
     average thickness of more than 1 meter lie within 30 meters
     of the base of the proposed liner system.

•    Areas in which the liner bottom or in-place barrier soil is
     less than 10 feet above the historically high water table.

•    Areas near a functioning private or public water supply that
     would constitute  an unacceptable risk to the public health
     or safety.


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 •     Areas  one-half  mile  from any occupied dwelling,  church,
      school,  hospital,  or similarly occupied structure.

 •     Areas  where  the active  portion of  the facility  is  less than
      200  feet from the  facility's property line,  and less than
      300  feet from right-of-ways  for roads and utilities.

      Section  13 of the  Code  includes performance  standards in
 addition  to the provisions of 
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 •     Water  Table -  Landfill  operations will maintain  a  safe
      vertical  distance  between  deposited  refuse  and the maximum
      seasonal  water table  elevation  and shall  include such
      measures  necessary to prevent contamination of the ground
      water.

 •     Flooding  -  sites subjected to flooding shall be  avoided.

 •     Site Improvements  - The following physical  improvements
      shall  be  made  before  a  landfill site is placed in  operation:

      The Site  shall be  adequately fenced, with an entrance gate
      that can  be locked and  posted; all-weather  operational roads
      shall  be  provided,  and; arrangements shall  be made for fire-
      protection  services.

 •     Operation - All operations of the landfill  shall be in
      accordance  with the approved plans and the  Arkansas Solid
      Waste Management Code.

      The consolidation/containment unit (CCU), which is a
component of many alternatives for OU2 media,  will be designed
and constructed  as part of OU1.  Therefore,  while those siting
criteria discussed above are applicable,  they have been addressed
in the ROD for OU1,  under which authority the CCU's siting will
be addressed.

Arkansas Water and Air Pollution Control Act (AWAPCA)

      Subchapter  2 of the AWAPCA, ACA 8-4-101 - 106,  8-4-201 -
229,  and 8-4-301 - 313,   (relating to water pollution)  provides
the Arkansas Pollution Control and Ecology Commission the
authority to prescribe:

•     Effluent  standards specifying the maximum amounts or
      concentrations and nature of the contaminants being
      discharged  into the waters of the State of  Arkansas or into
      POTW's.

•     Requirements and standards for equipment and procedures for
      monitoring  contaminant  discharges at their  sources.

•     Water quality  standards, performance standards,  and
      pretreatment standards.

      In compliance  with the  requirements  of Federal Water
Pollution Control Act,  the Arkansas  Commission on Pollution
Control and Ecology has established  water quality standards  for
all surface waters,  interstate  and intrastate, of the State  of
Arkansas.
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     Arkansas  air pollution  control  regulations  (ACA  Subchapter
 3) resemble the national  standards set  forth  by  the EPA under the
 CAA, but require preconstruction  review by  the State.  Section 5
 of the Arkansas Air Pollution Control Regulations outlines
 specific limitations  for  particulate emissions and for visible
 emission from  new or  modified sources.   Particulate emission
 limits are based on the rate of material being processed  (Ib/hr),
 visible emission standards are action specific.

 Regulations 18 and 26:  Arkansas  Air Pollution Control Code

     The Arkansas Air Pollution Control  Code  (Minor Source,
 ADPC&E Reg. No. 18),  (Operating Air  Perr-.  Program, ADPC&E Reg.
 No. 26) was derived from  the AWAPCA  and  outlines permit
 requirements, and emission limits for small or nuisance sources
 not covered by the SIP.   Of  particular interest are Section 4 -
 Visible Emissions; Section 6 -Emission of Particulate Matter from
 Incinerators; Section 7 - Emission of Particulate Matter from
 Equipment; Section 8  - Emission of ^articulate Sulfur Compounds;
 Section 10 - Emission of Air Contaminants Such as to Constitute
Air Pollution; and Section 11 - Control  of Fugitive Emissions.

Regulation 19;  Arkansas State Implementation Plan for Air
Pollution Control

     Promulgation and enforcement of the SIP  (Regulation No.  19,
September 1993) is necessary for the attainment and maintenance
of the National Ambient Air Quality Standards (NAAQS)(40 CFR Part
50),  New Source Performance Standards (NSPS)(40 CFR Part 60),
Prevention of Significant Deterioration  (PSD)(40 CFR S 52. 21),
and the National Emissions Standards for Hazardous Air Pollutants
 (NESHAP)  (40 CFR Part 61).  The SIP is formatted into the
 fallowing sections:

 •    Protection of the National Ambient Air Quality Standards;

 •    Applicability,  Permitting Procedure;

 •    General Emissions Limitations Applicable to Equipment;

 •    Upset Conditions, Revised Emissions Limitations;

 •    Sampling, Monitoring, and Reporting Requirements;

 •    Prevention of Significant Deterioration  Supplement;

 •    lll(d) Designated Facilities; and,

 •    Regulations for  the  Control  of  volatile  organic  compounds
     (VOC's).
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     The SIP was developed primarily to satisfy the requirements
of the Clean Air Act.

Arkansas Non-criteria Air Pollutants Control Strategy

     ADPC&E has implemented an evaluation of the emissions of
non-criteria air pollutants from all sources in order to
determine if a permit should be issued or if an existing source
should be required to retrofit control equipment.  The No-
criteria Air Pollutants Control Strategy (NAPCS) allows
applicants to apply a 3 level evaluation of the emission source.
The three levels are as follows:

•    Level 1 Analysis - This analysis is based upon Threshold
     Limit Values (TLV's)  for chemical substances adopted by the
     American Conference of Governmental Industrial Hygienists
     (ACGIH).  According to NAPCS,  the predicted ambient air
     concentration of gases and vapors is considered acceptable
     if it is less than 1/100 of the ACGIH TLV.  The ambient
     concentration is determined by using appropriate atmospheric
     dispersion models over a 24-hour average.   The spacing
     between receptors used in the model is 100 meters (in the
     area of the highest concentration).  The NAPCS may consider
     8 and 24-hour averages,  first highs,  as well as annual
     averages for use in assessing risk.

     TLV's have been established for the following OU2-related
site compounds:

              Compound                TLV
               2,4-D                10 mg/m3
              2,4,5-T               10 mg/m3

     When the substance emitted is a particulate compound and
persistence in the environment is expected, the predicted annual
average concentration is considered acceptable if it does not
exceed the dosage mass of the lethal dose 50 (TD50) (or where 50%
of a study species dies upon exposure to a specific dosage)
expression divided by 10,000.

     If the substance emitted is an herbicide, pesticide, or
fungicide, the recommended application rate  (in pounds/m2) is
divided by 30,000 to obtain the maximum allowable 24 hour average
ambient concentration.

•    Level 2 Analysis - If the source fails  the Level  1  analysis,
     the applicant must demonstrate  it  is using control
     techniques equivalent to lowest achievable emission rate
      (LAER) and submit toxicological and/or  other  data sufficient
     to demonstrate the ground  level concentration predicted in
     Level  1 will not adversely  affect  the public's health or
     welfare.

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 •     Level  3  Analysis  -  If the applicant  is unable to
      successfully demonstrate acceptance  under Level 1 or 2
      analyses,  then more appropriate mathematical models  (using
      site-specific information), or ambient air monitoring can be
      performed.  Information gathered during Level 3 analysis is
      then plugged back into the Level 1 and/or 2 analysis to
      determine  acceptance.

      The substantive component zl NAPCS may be applicable to
 remedial actions performed on-site.  A site-wide air monitoring
 program may be  required  to ensure compliance with this control
 strategy.

 Arkansas State  Ground Water Quality Protection Strategy

      The objective of Arkansas' ground water strategy is to
 formulate and recommend  a management program to protect the
 quality of ground water  resources.

     Arkansas' Ground Water Quality Protection Strategy outlines
water quality criteria for ground water (drinking water)  within
the State.   Arkansas has adopted the recommended standards for
drinking water set by the SDWA.   The Arkansas Department of
Health uses the National Primary Drinking Water Standards in
setting the criteria to which public water supplies must adhere.

     The Arkansas State Ground water Quality Protection Standard
 is not directly applicable to OU2 media,  but may be indirectly
relevant as a result of the migration of site-related compounds
migrating from OU2 media into ground water.

 7.2.3  TO-BE-CONSIDERED  (TBC's)

City of Jacksonville Ordinances 604. 620. 684. and 877

     Ordinance No. 620 sets forth uniform requirements for direct
discharge and indirect contributors into the wastewater
 collection and treatment system for the City of Jacksonville,
Arkansas, and enables the City to comply with all applicable
 state and Federal laws required by the CWA and its General
 Pretreatment Regulations (40 CFR Part 403).

      Ordinance  No. 684 is an ordinance amending Ordinance No.
 620 that specifically  lists additional chemical-specific
 pollutant limitations  for contributors into the wastewater and
 treatment system for the City of Jacksonville.

      Ordinance  No. 877 is an ordinance that amends Ordinances 620
 and 684, specifying that no industrial user shall discharge
 wastewater  of sufficient strength  to cause the  24-hour loading to
 the POTW to exceed background levels by  more  than those
 specified,  under this  ordinance,  for selected chemicals.

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      Ordinance No.  604  is an ordinance regulating the
Jacksonville  sewer  system and sets forth requirements and
regulations for  the use of public sewers and private sewage
disposal.

8.0   SUMMARY  OF  COMPARATIVE ANALYSIS OP ALTERNATIVES

      EPA  is required to analyze each of the individual
alternatives  against a  set of 9 criteria and develop a
comparative analysis that focuses upon the relative performance
of each alternative against those criteria.

      The  nine evaluation criteria are as follows:

1.  Overall Protection  of Public Health and the Environment

      This criterion addresses the way in which a potential remedy
would reduce, eliminate, or control the risks posed by the site
to human health and the environment.   The methods used to achieve
an adequate level of protection may be through engineering
controls, treatment techni^es,  or other controls such as
restrictions on the future use of the site.  Total elimination of
risk  is often impossible to achieve.   However,  a remedy must
minimize risk to assure that human health and the environment
would be protected.

2.  Compliance with ARAR's

      Compliance with ARAR's,  or "applicable or relevant and
appropriate laws and regulations," assures that a selected remedy
will meet all related federal,  state, and local requirements.
The requirements may specify maximum concentrations of chemicals
that  can remain at  a site; design or performance requirements for
treatment technologies; and,  restrictions that may limit
potential remedial  activities at a site because of its location.

3.  Long-Term Effectiveness or Permanence

      This criterion addresses the ability of a potential remedy
to reliably protect human health and the environment over time,
after the remedial  goals have been accomplished.

4.  Reduction of Toxicity, Mobility, or Volume of Contaminants

      This criterion assesses how effectively a proposed remedy
will  address  the contamination problems.   Factors considered
include the nature  of the treatment  process; the amount of
hazardous materials that will be destroyed by the treatment
process;  how  effectively the process reduces the toxicity,
mobility, or  volume of  waste; and, the type and  quantity  of
contamination that  will remain after treatment.
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5.  Short-Term Effectiveness

     This criterion addresses the time factor.  Technologies
often require several years for implementation.  A potential
remedy  is evaluated for the length of time required for
implementation and the potential impact on human health and the
environment during the remediation.

6.  Implemantability

     Implementability addresses the ease with which a potential
remedy  can be put in place.  Fact-rrs such as availability of
materials and services are considered.

7.  COSt

     Costs (including capital costs required for design and
construction, and projected long-term maintenance costs)  are
considered and compared to the benefit that will result from
implementing the remedy.

8.  State Acceptance

     The State of Arkansas has had an opportunity to review the
FS, the Proposed Plan and the ROD,  and offer comments to EPA.
The State of Arkansas fully supports EPA's preferred alternative.

9.  Community Acceptance

     During the public comment period, interested persons and
organizations have commented on the alternatives.   EPA has
carefully considered these comments in making its final
selection.  The comments received in response  ~ EPA's initial
Proposed Plan for OU2, issued in May 1995, are addressed in a
document called "The Original Responsiveness Summary," which was
released to the public on March 5,  1996,  when EPA issued its
Supplemental Proposed Plan for OU2, and is included as Attachment
A as part of this Record of Decision.  EPA received additional
formal  and informal comments following the release of the
March 5, 1996, Supplemental Proposed Plan, and these comments are
addressed in "The Supplemental Responsiveness Summary" which is
included as Attachment B to this ROD.  For additional information
on community participation, refer to  Section 3.0 of this
document.

     The nine criteria are categorized into three groups:
Threshold criteria, primary balancing criteria, and modifying
criteria.  The threshold criteria must be satisfied  in order for
an alternative to be  eligible for selection.  The primary
balancing criteria are used to weigh major tradeoffs  among
alternatives.  The modifying criteria are taken into  account
after public comment  is received on the  Proposed Plan.

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 Threshold  Criteria

 •     Overall  protection  of human health and the environment.

 •     Compliance with ARAR's  (applicable or relevant and
      appropriate  requirements of other Federal and State
      environmental  statutes).

 Primary Balancing Criteria

 •     Long-term effectiveness and permanence.

 •     Reduction of toxicity, mobility, and volume through
      treatment.

 •     Short-term effectiveness.

 •     Implementability.

 •     Cost.

Modifying Criteria

 •     State acceptance.

 •    Community acceptance.

8.1  COMPARATIVE ANALYSIS OF REMEDIAL ALTERNATIVES

1.    Overall Protection of Human Health and the Environment

     Alternative  S-l (no action),  does not provide adequate
protection of human health and the environment.  Alternatives S-2
through S-8 do not provide for adequate protection — human
health and the environment when considering the proposed TCDD
cleanup standards of 50 ppb, 35 ppb, and 20 ppb presented in the
FS (see EPA risk  evaluation of soil cleanup levels for 2,3,7,8-
TCDD  at the Vertac Superfund site).  EPA has determined that a 5
ppb action level, based on site-specific risk factors for TCDD
TEQ,  is necessary to be protective of a future on-site
unprotected worker exposure scenario.  However, in examining the
protectiveness of Alternatives S-2 through S-8 the following
 comparisons were  made:

      Alternatives S-2 through S-8 pose varying degrees of
 potential  short term risk during the construction phase of the
 remedial actions  associated with the various alternatives
 proposed.  Those  short term risks will be addressed  in greater
 detail in  Section 8.1.5,  "Short-Term Effectiveness,"  below.
 However, through  appropriate health and safety measures and
 proper engineering  controls that would be implemented in
 connection with any of the alternatives, adequate protection

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would be  provided to  the  community and the workers during the
remedial  actions.

      However,  containment of the  low  level risk media addressed
in  this ROD, particularly when a  5 ppb cleanup level is applied
to  the on-site consolidation remedy proposed in Alternative S-2,
will  be fully  protective  of the human health and the environment.
Containment of low level  threat wastes within a properly
engineered RCRA-compliant hazard-
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 However,  the  long term benefits  associated with these
 alternatives  are offset by the additional short term risks posed
 by material handling associated  with on-site desorption or with
 material  handling and transportation to an off-site incineration
 facility,  as  well as substantial additional costs associated with
 implementing  Alternatives  S-5 and S-6.

     Alternative U-l (no further action with respect to equipment
 and underground  utilities), would not provide adequate protection
 to the human  health  and the environment.  Potential risks would
 continue  at current  conditions for an extended period of time.
 Alternatives  U-2  (equipment plugging and cleaning) and U-3
 (equipment plugging,  cleaning and sealing) would provide overall
 protection to the human health and the environment due to the
 fact that  both would substantially remove sources of future
 contamination.  However, Alternative U-3 provides a greater
 degree of  overall human health and environmental protection by
 sealing off the cleansed and flushed equipment, sewer lines and
 curbs and  foundations,  further ensuring that those objects not be
 a source of future recontamination.

 2.   Compliance with Applicable or Relevant and Appropriate
     Requirements  (ARAR's)

     At present there are no State or Federal regulations that
 are applicable to Alternative S-l (no action),  although this
 alternative is not protective of human health.   Land disposal
 restrictions  (LDR's)  are not applicable to consolidated or
 containerized soils for the on-site landfilling component of
Alternatives S-2 through S-8,  as they would be consolidated
within an area of containment (AOC)  without treatment,  and
 therefore placement will not occur.   See discussion of
 consolidation within Section 7.2.1,  Federal ARAR's.   For
 alternatives S-3 through S-6,  thermally-treated soils would need
 to comply with land disposal restrictions prior to on-site
 disposal due to the fact that placement would occur with respect
 to treated wastes, as opposed to untreated contaminated soil and
 debris.  Treatment and  disposal of TCB spill-related material
 would comply with  all applicable  requirements with respect to
 pre-transportation and  manifesting requirements.  Because TCB
 spill-related materials above a  500 ppm action level would be
 treated and disposed  of off-site, further ARAR's analysis is
 inapposite, and all  applicable requirements would apply once the
 material  leaves the  site.

     Leachate collected from the on-site landfill in Alternatives
 S-2 through S-8,  and condensed water from Alternative S-3, would
 be treated at the on-site  treatment system, and the resulting
 discharge  to  Rocky Branch  Creek  would have to meet
 treatment/discharge  requirements. Organic condensate generated
 from on-site  thermal desorption  in Alternative  S-5 would  be
 transported off-site for incineration, and would  have to  be  in

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compliance with  appropriate  incineration and disposal
requirements.

     Off-site transportation of crystalline TCB and associated
spill soils in Alternatives  S-2 through S-6 and desorbed liquids
generated in Alternative S-5 would comply with all applicable
manifesting and  transportation regulations.

     Alternatives U-2 and U-3 would comply with ARAR's.  The LDR
treatment standards for hazardous debris are not applicable to
underground structures such  as manholes, sumps, and sewers
because the proposed actions do not involve placement within a
unit, and therefore land disposal will n^v. have occurred.
However, RCRA treatment and  disposal requirements are applicable
to the wastewater generated  during the remedial actions.
Wastewater generated from flushing of the industrial sewer, and
from hydroblasting of foundations and curbs, would be treated at
the on-site treatment plant  in compliance with applicable
treatment and standards, and the treated water would be
discharged into Rocky Branch Creek in compliance with applicable
State water quality standards.   Solids removed from the sewer
lines or removed from foundations and curbs would be placed in
the on-site consolidation unit.  Because those solids constitute
contaminated debris from within the site's AOC, placement will
not occur when they would be consolidated within the CCU, and
therefore RCRA's LDR's do not apply as an ARAR.

3.   Long-Term Effectiveness and Permanence

     Alternative S-l (no action)  does not provide for long-term
protection.   Alternative S-2 (on-site containment),  S-7 (capping
in place), and S-8 (on-site  containment of site media with dioxin
concentrations above 50 ppm) provide for the r "action in the
migration and exposure pathways through capping and/or
landfilling contaminated soils.  As discussed earlier,
containment of low level threat wastes in a RCRA Subtitle C
hazardous waste  landfill has proven to be an effective and
reliable technology, but one that requires long term operation
and maintenance  (O & M) and  the imposition of institutional
controls to remain effective.  Alternatives S-3 and S-4 provide
for more reliable long term  protection through additional
reduction in toxicity by permanently destroying some of the
contaminants through treatment.  Alternatives  S-5 and  S-6  involve
the greatest treatment components and would be more effective  in
the long term because they would permanently destroy site
contaminants.  However, the  high cost to  implement the off-site
incineration alternative  (S-6) and  increased  length of time  to
implement the on-site thermal  desorption  alternative  (S-5) make
these options problematic.

     For Alternative U-l  (no action with  respect to underground
utilities, equipment, and  curbs  and foundations), the quantity of

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 site-related  compounds  in underground  structures  is expected to
 remain  constant  for  the foreseeable  future.  For  Alternatives U-2
 (plugging  and cleaning  underground utilities, equipment, and
 curbs and  foundations),and U-3  (plugging, cleaning, and sealing
 underground utilities,  equipment, and  curbs and foundations) the
 residual contaminant concentrations  remaining after remediation
 would be minimal.  Alternative U-3 would provide  an additional
 level of effectiveness  by the grouting up of the  sewer line,
 which would reduce the  potential for collapse and transmission of
 groundwater,  and the sealing of foundations and curbs would
 prevent contact  with contaminants that cannot be  removed by
 scarification.

 4.   Reduction of Toxicity, Mobility,  or Volume of the
     Contaminants through Treatment

     A  significant reduction in toxicity, mobility and volume of
 TCDD is not expected under Alternative S-l (no action), since any
 reduction under  the no action alternative would occur through
 natural attenuation mechanisms.  Alternatives S-2, S-7 and S-8
 rely on capping  and/or excavation and  landfilling.  Therefore,
 this criterion is not applicable because neither  involves
 treatment.   Alternative S-8 provides the greatest reduction of
the mobility of the three alternatives due to extensive soil
 isolation,  yet does not involve treatment.  Alternatives S-3 (on-
 site desorption and chemical treatment) and S-4 (on-site
 containment,  consolidation,  and on-site incineration), which
 incorporate capping,  landfilling,  and treatment options,  address
 reducing the toxicity,  mobility and volume of TCDD at the site to
 some extent.   Alternatives S-5 (on-site desorption),  and S-6
 (off-site incineration) address soils with TCDD concentrations
greater than 50 ppb or 20 ppb depending upon the option
 considered, would provide for the greatest reduction in toxicity,
mobility and volume of TCDD of all che options revi_.ed.
However, drawbacks to these options  include the estimated 4 years
 of on-site treatment time required under Alternative S-5 and the
 extremely high cost of  implementation  associated with Alternative
 S-6.

     Alternative U-l would not provide for the reduction of
 toxicity, mobility and  volume of contaminants associated with the
 on-site structures.  Under Alternatives U-2 and U-3, contaminants
 are removed from these  structures, thereby significantly reducing
 their toxicity,  mobility and volume.

 5.   Short-Tent  Effectiveness

     All action  alternatives require between 2 and 5  years  to
 implement.  Remedial actions involving capping and excavation and
 landfilling are  generally faster to  implement than those options
 requiring  combinations  of on-site/off-site treatment,  capping,
 and landfilling.

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     Alternative  S-l  (no  action) poses no  short term  impact to
the  community  and site workers.  Alternatives  S-2 through S-8
pose some potential short term  impacts to  the  community and
workers  from dust generated during material handling  activities.
Alternatives S-3  through  S-6 pose additional impacts  associated
with the operation of treatment systems.   Short term  impacts
posed by Alternatives S-5 and S-6 are greater  than for the other
alternatives due  to the relatively large volume of soil to be
excavated and  treated, which COMM create  a longer period of time
for  potential  exposure.   Alternative S-5 involves transportation
of relatively  small amounts of high concentration liquids off-
site, and poses the additional risks associated with  excavation
and  treatment  of  a large  volume 01 contaminated soil, both of
which actions  could create a longer period of  time for potential
exposure.  However, with  respect to all alternatives  that involve
excavation and material handling that generate dust,  appropriate
engineering controls would be used for dust suppression, along
with other measures necessary to detect and prevent airborne
releases

     No short  term impact would result from implementation of
Alternative U-l (no action).  Short term impacts associated with
Alternatives U-2 and U-3 are primarily from dust generated during
remedial activities.   Appropriate engineering controls will be
used for dust  suppression, along with other measures necessary to
detect and prevent airborne releases.

6.   implementability

     Alternative S-l is the easiest to implement because it
requires no further action.  Alternatives  S-2,  S-7,  and S-8
(capping and landfilling options)  are relatively simple to
implement because they use conventional construction techniques.
Alternatives S-3,  and S-4 are more difficult because they require
temporary soil storage and on-site treatment of soils.  The
requirements for  implementing Alternative  S-6  are similar to S-3
and S-4 except that the volume of soils requiring excavation and
treatment is substantially larger.  Alternative S-5 is the most
difficult to implement because it involves the same amount of
soil involved  in  S-6, except that both on-site and off-site
treatment options  would be in effect.

     Alternative  U-l can  easily be implemented as it  does not
require  any further action.  Alternatives  U-2  and U-3 can be
implemented using standard and  specialized equipment.
Technologies and  technical expertise associated with  the
alternatives are  readily  available.

7.   Coat

     The costs associated with  the alternatives  described ranged
from $5,896,000 (Alternative  S-2) to  $164,601,000  (Alternative

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 S-6).   Annual  operation and maintenance  costs  ranged  from  $10,400
 (Alternatives  S-5  and S-6)  to  $37,700  (S-2  to  S-4).

     The  cost  to implement  Alternatives  U-2 and U-3 are
 $1,229,000  and $1,359,000,  respectively.

 8.   State Acceptance

     Under  the Superfund law,  EPA  is required  to ensure that
 states  have a  meaningful and continuing  role in remedy selection
 and  execution.  While states are not required  to concur formally
 with EPA-selected  remedies,  if the remediation is funded by the
 Superfund,  the state  where  the site is located must contribute 10
 percent of  the remedy's construction cost.   States are required
 to formally concur with the deletion of  a site from the National
 Priorities  List (NPL)  upon  completion of the remediation process.
 For  these reasons, EPA has  kept ADPC&E staff informed regarding
 the  remedy  selection  process and has briefed the State on several
 occasions concerning  the remedial alternatives considered in the
 FS and  the  preferred  option set out in the  original and
 Supplemental Proposed Plan  *->r OU2 and this  ROD.

     The  ADPC&E has reviewed the FS, the May 1995 Proposed Plan
 and the March  1996 Supplemental Proposed Plan,  and has provided
 EPA with  comments  on  this ROD.   The ADPC&E  is  in full agreement
with this ROD.
9.  Community Acceptance

     EPA recognizes that the community in which a Superfund site
is located is the principal beneficiary of all remedial actions
undertaken.  EPA also recognizes that it is its responsibility to
inform interested citizens of the nature of Superfund
environmental problems and solutions, and to learn from the
community what its desires are regarding those sites.

     EPA has undertaken an extensive effort to solicit input from
the community on the various remedial options considered for this
operable unit.  The concerns the community raised at various
times during discussions with EPA include the following:
1) The on-site landfill should be located at the greatest
distance away from the nearest residences, its size should be
minimized, and its height should not exceed 25 feet; 2) For the
restricted access portion of the site  (the area that would remain
fenced) workers should not have to wear  "moonsuits"  (the highest
level of protective clothing) to conduct their daily activities;
3) An attempt should be made to return a substantial portion  of
the site to commercial/industrial productivity; 4) The cleanup
level for dioxin within the fenced area  should be  no greater  than
5 ppb; 5) For the area outside the fence, the dioxin cleanup
level should be a maximum of 1 ppb;  and, 6) That the smallest

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 area  possible be fenced  to  provide  the maximum  acreage  for
 potential  future commercial/industrial redevelopment.

      EPA,  in the remedy  selected  in this document, has  made an
 effort  to  address these  community objectives within  Statutory
 guidelines.   While the community  desired that the strip of
 property along Marshall  Road be cleaned to  1 ppb dioxin to
 promote what they believed  was a  more attractive draw for
 prospective  land developers, they understand that the 5 ppb
 cleanup level is justified  by the risk assessment and defensible,
 and that a lower cleanup level, like 1 ppb, for example, is not.
 As such, the community understands  that EPA cannot mandate a
 lower cleanup level than is justified.  However, through
 discussions  and  meetings regarding  the communities desire for 1
 ppb along  Marshall Road, Hercules,  Inc., has indicated  it would
 evaluate this additional cleanup.   Such action on the part of
 Hercules,  Inc.,  would be fully supported by EPA and totally
 voluntary.

 9.0   THE SELECTED  REMEDY

      Based upon  consideration of  the requirements of CERCLA, the
 detailed analysis  of the alternatives using the nine evaluation
 criteria,  consultation with the Arkansas Department of Pollution
 Control and Ecology, and public comments, EPA has determined that
Alternatives  S-2  (with the modifications described below for on-
 site  surface  soils) and U-3, are  the most appropriate remedies
 for the Vertac Operable Unit 2 media.   Given the reasonably
anticipated future land use for the site and the low level
threats at the site that this ROD addresses, and consistent with
the NCP's preference for EPA to implement containment remedies
when  addressing  low level threat wastes where treatment of those
wastes is impracticable  (see NCP  Section 300.'~0(a)(iii)(B), 40
 CFR S 300.430(a)(iii)(B)),  on-site  consolidation of OU2 media,
 including those  similar media from  the 1990 Off-Site Areas ROD
 and the bagged soils Hercules, Inc., had excavated in a 1990
 removal action from contiguous residential areas, is fully
protective and appropriate.

      A component of the  selected  remedy uses excavation and
 landfilling  to address low  level  threats posed by contaminated
 soil  media.   In  addition, as discussed earlier, the  remedy
 selected also addresses  contaminated soil originally intended to
 be incinerated on-site.  These materials consist of  soils to be
 removed from the Rocky Branch Creek flood plain, sludges removed
 from  the on-site sewage  treatment plant and sediments from  the
 interceptor  line as part of the 1990 Off-Site Areas  ROD, and
 residential  bagged soil  from the  1990 Hercules-performed removal
 action  whose disposition the  1993 OU1 ROD expressly  deferred
 until EPA  executed the OU2  ROD.   Because the on-site incinerator
 is no longer operational and  because those  contaminated soils and
 debris  described above came from  a  contiguous  area of

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 contamination and constitute low level  threat media,  and
 therefore  in  no  way differ  from the  contaminated  soil and debris
 addressed  in  this ROD,  EPA  has  determined that  it is  appropriate
 to amend the  1990 Off-Site  Areas ROD to reflect this  change.

     After remediation,  the northern portion of the site will
 have unrestricted access for commercial/industrial development.
 EPA cannot determine the permanent fence locations on the
 southern portion along Marshall Road until the  remedial
 design/remedial  action phases begin.  However,  fence  locations on
 this portion  of  the property may be  phased in order to provide
 unrestricted  access in the  future for commercial/industrial
 development.   Figure 13  depicts the  appr,..imate areas of the site
 that will  remain fenced  in  relation  to  the portion of the site
 that will  have unrestricted commercial  access.  It should be
 emphasized that  tne area  shown  on this  drawing  is approximate,
 and the fencing  will be  conducted in phases, since a continuous
 effort will be made to provide  the maximum amount of property for
 commercial  redevelopment.

     EPA acknowledges that  contaminated sediments in Rocky Branch
Creek have resulted in ecological impacts.   However,  until the
 site is remediated  and the  source of dioxin contamination
eliminated, the potential for continuing impacts exists through
contaminated surface soils,  sediment transport and groundwater
seeps.   With this remedy, the primary source will be removed
through consolidation of dioxin contaminated soils in the on-site
 landfill and sediment transport resulting from the sump overflows
and storm water run-on and run-off will be reduced or eliminated
through storm water management,  thereby eliminating ecological
risk.

      Groundwater seeps from the contaminated areas of the site
 into Rocky Branch Creek are currently impeded by th^ French drain
system installed along the western edge of the site and bordering
the on-site burial grounds,  thereby preventing another potential
source of contamination for Rocky Branch Creek.   Stream data
 indicates no measurable dioxin  concentrations,  for example,
 following rain events.   Since Rocky  Branch Creek is not a
perennial waterbody and does not  flow through the site, the
removal of the contaminated soils and elimination of untreated
discharges and possible groundwater  seeps will  essentially
 eliminate  future impacts.   While  data suggests  that existing
 impacts in Rocky Branch  Creek are on the decline, any actions to
 remove contaminated sediments in Rocky  Branch Creek would be cost
 prohibitive, but more importantly, any  disturbance of the
 existing sediment could  prove catastrophic, possible  even
 destroying the entire existing  ecosystem.  As such, this remedy
 in addition to the  other on-going remedies at the site will
 effectively remove  the contamination source and the storm water
 transport  concern allowing  Rocky Branch Creek to  continue,  in
 essence, a natural  attenuation  process.

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     A summary  of  the  selected  remedy  is presented below.

 9.1  SOILS AND  SEDIMENT MEDIA

 1)   On-sita Surface Soils

     The selected  remedy for the Vertac on-site soils media is
 Alternative S-2, with  the following modifications.

 All soils on both  the  northern  and southern parcels with dioxin
 concentrations  at  or above the  action  level of 5 ppb will be
 excavated and disposed of in the on-site landfill.  While EPA did
 not include this 5 ppb cleanup  level in the description of
 Alternative S-2 in the OU2 FS,  EPA has received substantial
 public comment  regarding the use of a  5 ppb dioxin cleanup level.
 In addition, EPA has reevaluated its risk assessment taking into
 account the reasonably anticipated future land use for the site
 and considering the low level threat media addressed by this ROD
 for OU2.  Therefore, EPA now selects 5 ppb as the appropriate and
 fully protective action level for the  implementation of
Alternative S-2.

     The OU2 on-site soils area includes the area around the
existing Regina Paint Building,  which  is targeted for demolition
under the OU1 ROD.   Sampling results indicate that some
excavation will be necessary in the areas around the Regina Paint
Building.  Following remediation,  the entire northern parcel will
be available for redevelopment.

     All excavated site areas will be backfilled with clean soil,
compacted and revegetated.   Some surface drainage modifications
may be used to control runon and runoff, thereby minimizing the
potential for erosion,  and to facilitate positive drainage to
eliminate the possibility for ponding water.

     During remedial action for this remedy, there is a
possibility of dust being created which could suspend dioxin
contamination.  As part of the  remedial action, continuous air
monitoring will be conducted and dust  suppression measures will
be implemented to ensure that no airborne contaminants migrate
 off-site to a receptor point.   Therefore, no-site related
 contaminants will be allowed to pose a threat to nearby citizens
 or a casual passerby.

     EPA will work with the Vertac Receiver and City of
 Jacksonville to impose deed restrictions and notifications, or  to
 enact  specific  land use restrictions to limit the future use  of
 the property as appropriate for the long term remediation
 efforts.  Finally, upon completion of  the remedy for OU2,  long
 term operations and maintenance measures will be instituted to
 ensure, in part, that  the integrity of the  RCRA Subtitle C
 hazardous waste landfill will be maintained.

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     Another  element  of  this portion of the remedy  is a  "phased
 fencing"  approach  for the  southern parcel.  Once  initial
 remediation is  complete, the smallest possible area of the site
 will be fenced.  A continuous effort will be made to provide the
 maximum amount  of  property possible for potential commercial
 redevelopment,  as  long term remediation efforts allow the
 restricted area to be reduced.

 2)   Crystalline Tetrachlorobenzene (TCB) and soils associated
     with the TCB  spill

     This component of the remedy -sails for the excavation and
 off-site  incineration of the crystalline TCB and  TCB-associated
 spill soils where  the TCB  concentrations exceed a 500 ppm health-
 based action  level.   Excavated areas will be backfilled with
 clean fill, graded and revegetated to prevent future contact with
 the remaining soils that fell below the 500 ppm TCB action level.
 It has been estimated in the RI that there are approximately
 1,400 cubic yards  (2,100 tons)  of crystalline TCB and associated
 soils for costing  purposes.  The actual volume of material will
be determined during  the remedial action.

 3)   Bagged Soils  from Residential Areas Excavated by Hercules,
     Inc., During  a 1990 Removal Action

     This component of the remedy calls for the consolidation of
approximately 2,770 cubic yards (4,155 tons)  of dioxin-
contaminated soils removed from residential yards in 1990 into
the on-site RCRA-compliant CCU.   As discussed earlier, the
Agency's  1993 ROD  had  deferred treating these contaminated low
 level threat soils and debris until all site soils were to be
addressed.  Due to the similarity of the on-site soils addressed
 ir. this ROD and the bagged soils from residen*  1 areas, EPA has
determined that it is  appropriate to treut all low  level threat
media in  a manner  consistent with the approach selected  for the
on-site soils in this ROD, that is, on-site disposal in the RCRA
 Subtitle  C Landfill.   Dioxin concentrations in the  bagged soils
range between 13 ppb  and 55 ppb TCDD, which is consistent with
 the dioxin concentrations  found in the soil and debris
principally addressed in this ROD.

 4)   Off-site Soils from the Residential Portions of Bayou Meto
     and  Rocky  rranch Creek riood Plain Areas from  the  1990 Off-
     Site Areas ROD

     This component of the remedy calls  for the excavation of  1
 ppb or greater  (approximately 4,100 cubic yards or  6,150 tons)
 dioxin-contaminated soils  from  along Rocky Branch Creek and  Bayou
 Meto and  consolidation of  this  material  into  the  on-site RCRA
 compliant CCU that is being constructed  as part of  the remedial
 action phase  of the 1993  OU1 ROD.  As  discussed earlier, these
 contaminated  soils and debris constitute low  level  threat media

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 and  had  originally  been  addressed  in the  1990 ROD for Vertac Off-
 Site Areas, which had required that they  be  incinerated  in the
 now-defunct on-site incinerator.   Due to  the similarity  to the
 on-site  soils addressed  in this ROD, EPA  has determined  that it
 is appropriate to treat  all  low level threat media in a  manner
 consistent with the approach selected for the on-site soils in
 this ROD, that is,  on-site disposal in the RCRA Subtitle C
 Landfill.

 5)   DevatereŁ Sludges from  the Old Savage Treatment Plant Sludge
     Digester and Sediments  from the Interceptor line from the
     1990 off-site  Areas ROD

     This component of the remedy calls for  the consolidation of
 approximately 890 cubic yards (1,200 tons) of digester sludge
 from the Old Sewage Treatment Plant into the on-site RCRA
 compliant CCU.  Also, about  2 cubic yards of contaminated
 sediment from the interceptor lines will be disposed in the CCU.
 The  dioxin concentrations found in the sewage treatment plant
 digester are consistent with those being landfilled from on-site
 areas.   As discussed earlier, these contaminated soils and debris
had originally been addressed in the 1990 ROD for Vertac Off-Site
Areas,  which had proposed that they be incinerated in the now-
defunct on-site incinerator.   Due to the similarity to the on-
site soils addressed in this ROD,  EPA has determined that it is
appropriate to treat all low level threat media in a manner
consistent with the approach selected for the on-site soils in
this ROD, that is,  on-site disposal in the RCRA Subtitle C
Landfill.

     The cost to implement Alternative S-2,  with above-mentioned
changes in action levels, is estimated to be $12.25 million.

9.2  UNDERGROUND UTILITIES,  FOUNDATIONS AND CURBS

     The selected remedy for addressing the contaminants
associated with these structures at the site is Alternative U-3.
 In addition to the  elements already described in Alternative U-3,
the underground chemical sewer lines will be cleaned to remove
 solids and filled with grout.  Cut-off barriers will be  installed
 around various underground utility lines to  prevent shallow water
migration along these lines.  Foundations and curbs will be
 cleaned through surface scarification, and for areas where
 persistent staining exists,  surface sealing  will also be
 employed.  Further,  the foundations and curbs will be covered
with adequate soil  (typically between 18  and 24 inches)  to
 support a vegetative cover and contoured  to  prevent erosion and
 prevent ponding of  storm water.   (The USTs were targeted to be
 addressed in this component  of the selected  remedy, but  as
 previously discussed in  Section 5.4.6 of  this ROD, Hercules,
 Inc., has recently  pumped dry and  backfilled these tanks with


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 grout.   Therefore,  the  five USTs  no  longer  require remedial
 action.)

      The cost  to  implement Alternative U-3  for the underground
 utilities lines,  building and  equipment  foundations, and curbs is
 estimated at $1.56  million.

      The total estimated cost  to  implement  both components of the
 selected remedy is  $13.81 million,   The  annual operation and
 maintenance costs are estimated at $37,700.  A more detailed
 estimate of the annual  operation  and maintenance cost will be
 provided in the site opertaion and maintenance plan to be
 developed during the remedial design.

 10.0     STATUTORY DETERMINATIONS

      Section 121(b)(1)  of CERCLA, 42 U.S.C. $ 9621(b)(l),
 requires  that  EPA select remedial actions that are protective of
 human health and the environment, that are cost effective,  and
 that utilize permanent  solutions and alternative treatment
 technologies or resource recovery technologies to the maximum
 extent practicable.  In addition, CERCLA Section 121(d)(l), 42
U.S.C. S  9621(d)(l), requires EPA to select remedies that comply
with applicable or relevant and appropriate environmental
 standards  (ARAR's) established under Federal and State
 environmental  laws, unless a waiver  is granted.   The following
 sections discuss how the selected remedy meets the statutory
requirements.

 10.1  PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

     The  selected remedy is protective of human health and the
 environment.  The remedial action objectives and goals specified
 in section 6.5 of this ROD will be met.

     The  selected containment remedy for the low level threat
 site soils, sediments and sludges, underground utility lines, and
 foundations is protective of human health and the environment
 because:

 1)   All  soils contaminated with  dioxin  concentrations of 5 ppb
 and greater will be excavated  and consolidated within an on-site
 RCRA  Subtitle  C hazardous waste landfill.   Excavation and
 consolidation  of» that low level threat material into the RCRA
 landfill will  substantially reduce the mobility of the site
 contaminants and will prevent  direct exposure through dermal
 contact,  inhalation, or ingestion by future site workers
 maintaining the restricted access area and  individuals passing by
 the site.  Excavation and consolidation  of  the contaminated  soil
 will  also prevent the threat of  leaching to ground water due to
 the engineering of  the  landfill,  and will reduce potential
 sediment transport  from runon  and runoff.   Such on-site

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 consolidation  of  low level  threat media  is  consistent with the
 NCP's  preference  for containment remedies for  low  level  threat
 media  where  treatment is  impracticable.  See NCP Section
 300.430(a)(iii)(B),  40 CFR  S  300.430(a)(iii)(B).

 2)   Concentrations  of dioxin-contaminated  soil that will remain
 in  place will  be  below 5  ppb, and are estimated to be on average
 less than  1  ppb,  which is well below the concentration required
 to  be  protective  of  human health and the environment.  EPA data
 indicate that  such an average dioxin concentration will  result
 due to the excavation of  grids containing dioxin concentrations
 above  5 ppb  and due  to the  fact that there  already exist grids
 v.hat contain dioxin  concentrations below 1  ppb.  Commercial
 access will  be possible for much of the site so as to allow
 redevelopment  of  the maximum amount of acreage.

 3)   Crystalline  TCB and  TCB-contaminated soils above the 500 ppm
 health-based limit will be excavated and transported off-site for
 incineration.  By permanently treating these wastes at an off-
 site facility, the possibility of direct contact exposure is
 completely eliminated.  In  ddition, the replacement of  clean
 topsoil will eliminate  the contact exposure pathway for  the TCB-
 contamination below  the 500 ppm action level.

 4)   Soils excavated from the contiguous areas of Rocky  Branch
 Creek,  bagged soils  from the contiguous residential areas,  and
 sediments and sludges from the old on-site sewage treatment plant
will be consolidated within the on-site RCRA Subtitle C  landfill.
 Excavation and consolidation of these sediments within a RCRA
 Subtitle C hazardous waste landfill will substantially reduce the
mobility of these contaminants and will prevent direct exposure
through dermal contact, inhalation,  or ingestion by members of
the public, who will be excluded from the landfill.

 5)   Underground utility  lines will be closed and/or grouted to
prevent the possibility of ground water contaminant migration and
 leaching through those  lines.  As discussed earlier, the USTs
have already been addressed, which has eliminated tne possibility
 of future leaching of any petroleum contaminants.

 6)   Building  foundations and curbed areas  will be cleaned using
 hydroblasting, scarification, epoxy sealing, and covered with
 adequate soil  to  provide  vegetative cover and contoured  to
 prevent erosion and  ponding water.  After such remediation, these
 structures will not  present an exposure hazard Ło future workers.

     Short-term risks associated with the selected remedy can be
 controlled by  closely monitoring the design and  implementation  of
 remedial measures and employing continuous  air monitoring and
 dust suppression  measures during construction  phases.  No adverse
 cross-media  impacts  are expected from implementation  of  the
 selected remedy.

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 10.2   COMPLIANCE  WITH ARAR'S

      The  selected remedy  for  site  soils,  sediments  and  sludges,
 underground  utility  lines,  and  foundations, will  comply with  all
 ARAR's identified for the site.  The ARAR's applicable  to the
 selected  remedy are  presented below:

      Due  to  the fact that the excavation  of the contaminated
 soils and debris  proposed in  this  ROD and their subsequent
 consolidation within the  CCU  will  occur entirely  within the area
 of contamination,  and because no treatment will occur that would
 result in those materials'  placement under LDRs within  the CCU,
 RCRA's land  disposal restrictions  do not  appj.y.   In addition,
 those restrictions do not apply to the soil and debris  from the
 1990  Off-Site Areas  ROD or  to the  bagged  residential soils
 Hercules  had excavated from contiguous areas as part of a 1990
 removal action, because they  were  also removed from within the
 area  of contamination (AOC)  and have not  been treated.  The
 substantive  (versus  procedural)  RCRA minimum technology
 requirements (MTR's)   for  hazardous waste  landfills are applicable
 to the CCU, due to the fact that all soil and debris
 consolidation actions will  occur entirely within AOC.  See 40 CFR
 SS 264.301(a, c,  g-j), 264.302(a),  264.310(a)  and (b) 264.312,
 264.313,  264.314,  264.315,  264.316, 264.317.   Therefore, design,
 construction, and operation of the CCU will substantively comply
with MTR's.  Finally, no ARAR exists for the backfill of clean
 soil over areas with dioxin contamination.

     Crystalline TCB and  spill-related soils will be excavated
 and taken off-site for treatment, and therefore ARAR's do not
 apply to the off-site component of this action.  However,  RCRA
manifesting and pre-transportation requirements are applicable to
 tha elements of this action that occur on-sit*-   Those RCRA
 requirements concerning manifesting, waste packaging, labeling,
waste analysis and notification to treatment,  storage and
 disposal  facilities  subject to land disposal restrictions are
 found at  40 CFR SS 262.20 - 262.23 and 262.30 - 262.32, and 40
 CFR 268.7, and apply in their entirety to off-site shipments  of
 hazardous wastes.

      In addition,  while not constituting  an ARAR, compliance  with
 the CERCLA Off-Site  Rule, promulgated pursuant to CERCLA Section
 121(d)(3), 42 U.S.C.  S 9621(d)(3), and formally entitled
 "Amendment to the National  Oil and Hazardous Substances Pollution
 Contingency  Plan;  Procedures  for Planning and  Implementing Off-
 Site  Response Action:  Final  Rule,"  58 FR 49200  (September 22,
 1993),  and codified  at 40 CFR 300.440, is mandatory for off-site
 disposal  actions.

      The  RCRA classification  and listing  as a  K085  waste  is
 applicable,  based on the  TCB  material's exhibiting  the
 characteristic of toxicity  pursuant to analysis under 40  CFR S

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 261.32.   The  land  disposal restrictions require that K085-listed
 wastes be treated  to  concentrations of constituents specified  in
 40  CFR S  268.43, which applies treatment standards set out at  40
 CFR S 268.40, prior to land disposal.  Such treatment will occur
 at  the off-site disposal facility.  Transportation of crystalline
 TCB and spill-related soils for off-site treatment/disposal would
 need to comply with all the requirements set forth under 40 CFR
 SS  107,171-177, and 263, the Hazardous Materials Transportation
 Act, 49 U.S.C. S 1801 et seq.. and state hazardous waste
 transportation requlations.

     The  Clean Air Act's (CAA's) National Ambient Air Quality
 Standards (NAAQS), 40 CFR S 50.06, as administered through
 Arkansas'  State Implementation Plan (SIP), may not be applicable
 to  this component of  the remedy since these standards are
 applicable only to "major sources" or sources that emit over 10
 to  25 tons per year of a regulated pollutant.  The standards,
 however,   are relevant and appropriate because respirable dust
 will be generated during the cleanup.   In addition, the Arkansas
 ambient air quality standards as described in the Non-criteria
 Pollution Control Strategy are applicable.

     Aqueous waste generated during the remediation activities
 and during perpetual  operation and maintenance, such as
 decontamination water or leachate from the CCU, will be processed
 through the on-site water treatment system.  Water from this
 treatment system will be discharged to Rocky Branch Creek,
monitored for compliance with State water quality criteria, and
 self-reported in accordance with State-developed effluent
 discharge limitations.

     Erosion and sediment controls during excavation,
 backfilling, regrading,  and revegetation would have to comply
with local regulations.

 10.3  COST EFFECTIVENESS

     The  selected remedy for Operable Unit 2 media is cost
 effective and is fully protective of human health and the
 environment based on  reasonably anticipated future land use for
 the  site  and the community objective of commercially redeveloping
 the  greatest amount of the site's acreage.  Section 300.430
 (f)(ii)(D) of the NCP, 40 CFR § 300.430(f)(ii)(D), requires 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, and short term  effectiveness.
 Overall effectiveness is then compared to  cost to ensure that  the
 remedy is cost effective.  For the reasons described  in greater
 detail in discussions above, the  selected  remedy  meets these
 criteria.
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      The  total  estimated  present worth of the selected remedy  for
 soils,  sediments  and  sludges  for the northern and southern
 parcels,  including  underground utilities and foundations, is
 $13,810,000.  The variation in remedy costs evaluated for these
 media ranged  from $5,896,000  for Alternative S-2, with higher
 site  action levels  to $164,601,000 for a total incineration
 remedy.   Even though  the  selected remedy does not provide for  a
 reduction in  the  toxicity or  volume of dioxin in site soils,
 landfilling will  substantially .-duce the mobility of the
 contaminants  of concern.  As  stated earlier, the NCP favors
 containment remedies  for  low  level threat media, or where
 treatment is  impracticable.   NCP Section 300.430(a)(iii)(B), 40
 CFR S 300.430(a)(iii)(B).  Due to the extreme cost of the
 treatment remedies, EPA has concluded that such treatment is
 impracticable.  However,  previously implemented remedies
 associated with other operable units have accomplished a
 reduction in  toxicity and volume of dioxin as a site contaminant
where those dioxin-contaminated media were considered to
 constitute a  principal threat.  As discussed earlier, however,
 containment is deemed to  be the preferred method of addressing
 low level threat media, and the remedy selected in this ROD cost
effectively accomplishes  that by utilizing the on-site RCRA
 Subtitle  C hazardous waste landfill being constructed as part of
the remedy for OU1.

 10.4  UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATIVE
      TREATMENT TECHNOLOGIES TO THE MAXIMUM EXTENT PRACTICABLE

     EPA has  determined that the selected remedy represents the
maximum extent to which permanent solutions and treatment
technologies  can be utilized  in a cost-effective manner for this
operable  unit.

     Of those alternatives that were protective of human health
and the environment, and  that comply with ARAR's, EPA has
determined that the selected  remedy provides the best balance  in
terms of  long-term effectiveness and permanence, reduction in
 toxicity, mobility, or volume achieved through treatment, and
 taking into consideration short-term effectiveness,
 implementability, costs,  and  State and community concerns.  The
 selected  remedy is consistent with the WCP's preference  of
 employing containment remedies when addressing low level threat
 media. NCP Section  300.430(a)(iii)(B), 40 CFR S
 300.430(a)(iii)(B).

 10.5  PREFERENCE  FOR  TREATMENT AS A PRINCIPAL ELEMENT

      Due  to the fact  EPA  has  determined  that principal  threats,
 as defined at NCP Section 300.430(a)(iii)(A),  40 CFR S
 300.430(a)(iii)(A), are not at  issue  in  this operable unit,  the
 remedy  selected for OU2 does  not require treatment to be
 implemented.  Therefore,  EPA  has determined that containment by

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 consolidating the low level  threat media within an on-site RCRA
 Subtitle  C  hazardous  waste landfill will effectively and
 protectively  address  those low  level threat media.  Therefore, it
 is  not  necessary  or appropriate for the OU2 remedy to meet the
 general statutory preference for treatment as a principal
 element.  Thus, EPA has determined that neither on-site thermal
 desorption, on-site incineration, or off-site incineration for
 the low level threat  media are  appropriate.  TCB-contaminated
 soils,  however, will  be excavated and transported off-site for
 treatment.

     All  soils that contain  concentrations of dioxin equal to or
 greater than  5 ppb will be excavated and placed into the on-site
 landfill.   By landfilling all grids having dioxin contamination
 levels  of 5 ppb or more, approximately 99 percent of all dioxin
 in  site soils and  debris will be contained.  Thus, completion of
 the remedy  selected in this ROD, in conjunction with other
 operable  unit remedies and related CERCLA response actions, will
 either  contain or  immobilize over 99 percent of the dioxin found
 in the  Vertac soils and debris.  The total amount of dioxin
present in site soils and "" ~bris covered under this operable
unit's  remedy selected herein comprises only about 1 to 5 percent
of the  amount of dioxin that was buried in on-site landfills
under the 1984 Court-ordered remedy.

11.0    DOCUMENTATION OF SIGNIFICANT CHANGES

     The Original Proposed Plan for Operable Unit 2 media at the
Vertac site was released to the public in May 1995.  As a result
of the Superfund Administrative Reforms issued in October 1995,  a
Supplemental  Proposed Plan was issued in March 1996.   The section
of the ROD that follows explains the differences from the
original proposal and the selected remedy contained in this
document.

     The modifications that have been made to the Record of
Decision  for  Operable Unit 2 media are the result of two
fundamental changes:  The preference for treatment of principal
threats has been met through other remedial actions undertaken or
to be undertaken at the site, while this ROD addresses low level
threat  media  for which the NCP prefers containment remedies, and
the future  land use scenario for only about two thirds of the
 southern  portion of the site will involve long term restricted
 access  due to the  on-site containment of hazardous wastes.
 Otherwise, the reasonably anticipated future land use, which is
 commercial/industrial, for much of the site will be attainable
 under the selected remedy.

     In the original  May 1995 Proposed Plan, EPA had envisioned
 that approximately 50 percent of the southern 93 acres of  the
 site would  eventually be returned to commercial/industrial use.
 However,  after reevaluating  the long term  operation and

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 maintenance requirements for that area  of  the  site, which will
 involve maintaining the caps on the  existing site  burial areas,
 the new RCRA Subtitle C hazardous waste landfill,  and operation
 and maintenance of a ground water treatment system, EPA believes
 that a more realistic estimate  would be that only  a portion of
 the property along Marshall Road could  be  available for future
 redevelopment opportunities on  the southern portion of the site.
 Because access to  about two thirds of the  southern property will
 remain restricted,  except for site maintenance workers, the
 selected remedy provides a more cost effective remedy that is
 fully protective of human health and the environment.

      The selected  remedy for the Operable  Unit 2 media differs
 significantly from EPA's original May 1995 Proposed Plan and the
 March 1996  Supplemental  Proposed Plan in several areas.  Those
 differences are:

 1)    Off-site incineration of dioxin-contaminated  soil is no
      longer a component  of the  selected remedy.

      The original Proposed Plan  called for the excavation and
 off-site incineration of  the 8 most highly-contaminated soil
 grids at the  site  (approximately  2,000 tons).

      EPA's  original rationale for  incinerating the 8 most highly-
 contaminated  grids  (out of  a total of 461)  at the site was based
 on EPA's preference for treatment of principal threats and for
permanent remedies, and those eight grids had initially been
regarded to constitute a principal threat.   Approximately 72
percent of the TCDD in site soils would have been treated at an
 off-site facility.

     After reevaluating all remedial options f    the site,  EPA
has determined that the preference for treatment of principal
 threats  is not necessary  due to the fact that this ROD addresses
 low level threat media, not principal threats,  when all of the
media addressed  in the ROD are considered as a whole.  S_ee
 Section  10.5  of this ROD.   One  should note, however, that the
 off-site incineration of  the TCB-contaminated soil has remained
 unchanged .

 2)    The volume  of  TCDD-contaminated material that was proposed
      for consolidation  into the on-site RCRA Subtitle C hazardous
      waste  landfill within the  fenced portion of the site has
          increased.
     The original May  1995 Proposed Plan called  for the
excavation and consolidation  of  approximately  104  grids,  or
approximately 17,059 cubic yards,  of  TCDD-contaminated soil into
the on-site  landfill.   The March 1996 Supplemental Proposed Plan
called for the excavation and on-site landfilling  of  TCDD-
contaminated soils  with TCDD  concentrations of 50  ppb or greater.

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Under  that proposal,  approximately 4,259 cubic yards of
contaminated  soil would have been consolidated within the CCU.
The  selected  remedy will  require that  112 soil grids that have
TCDD concentrations at or above 5 ppb  (approximately 18,319 cubic
yards) be excavated and consolidatsd within the on-site landfill.
This represents  approximately 99 percent of all the dioxin
present within site soils.

3)   TCDD-contaminated soils outside the fenced area will
     excavated and landfilled on-site wherever the TCDD
     concentration exceeds 5 ppb.

     The May  1995 Proposed Plan did not make a distinction
between the cleanup level for either the northern or southern
portions of the  site, and selected 5 ppm as the cleanup level for
TCDD.  The March 1996 Supplemental Proposed Plan set a 1 ppb TCDD
cleanup level for the northern (unfenced) portion of the site,
and proposed to  cap the southern (fenced) portion of the site
where TCDD levels ranged between 5 and 50 ppb.  Areas having TCDD
soil concentration levels above 50 ppb were to be excavated and
consolidated within the CCU.

     As discussed earlier in this ROD,  data indicate that
following the excavation of TCDD-contaminated soils, the average
TCDD contamination levels will be less than 1 ppb.  EPA data
indicate that such an average dioxin concentration will result
due to the excavation of grids containing dioxin concentrations
above 5 ppb and due to the fact that there already exist grids
that contain dioxin concentrations below 1 ppb.   Therefore,  by
excavating soils where TCDD concentrations exceed 5 ppb over the
entire site,  the remedy selected results in the same overall
cleanup goal as had been proposed in the original May 1995
Proposed Plan.

     All other elements of the original proposed plan remain
unchanged in the selected remedy.

     The changes discussed above were fully evaluated as other
remedial options considered in the OU2 FS and the original and
supplemental proposed plan.   EPA's selected remedy is a
modification of  Alternative S-2, which addressed  landfilling of
dioxin-contaminated media.  The difference between the selected
remedy and alternative S-2 is that EPA is requiring a more
conservative dioxin action level to trigger excavation and
landfilling fi.e.. 5 ppb  rather than 50 ppb).  In addition, the
remedy selected  in this ROD differs from EPA's preferred
alternative selected  in the March 1996 Supplemental Proposed  Plan
in that there no longer is a soils capping component to the
remedy.  This is in response to comments received during  the
public comment period.  The remedy selected herein  also allows
the  landfill  height to be maintained at  less  than 25 feet, which
likewise constitutes  an accommodation  to public preferences.

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                      ATTACHMENT A

                         FOREWORD
     The comments received in iexpense to EPA's initial  May  1995
Proposed Plan for OU2 are addressed in the following document
titled "Original Responsiveness Summary."  EPA's initial proposal
for remediation of soils called for the off-site incineration of
dioxin contaminated hot spots and on-site landfilling of dioxin
contaminated soils that exceeded a site-specific
commercial/industrial exposure level.   Under this scenario
approximately two-thirds of the site would have potentially  been
available for future commercial reuse.

     Following the release of the initial Proposed Plan  in
May 1995,  EPA issued a series of administrative reforms  for  the
Superfund Program.  One purpose of the reforms  was to control
remedy costs and to promote cost effectiveness,  and the  reforms
directed EPA to base site cleanup decisions on  practical future
land usage and reasonable contaminant  exposure  scenarios.  As a
result of those reform measures,  Region 6 reconsidered and
revised its Proposed Plan.

     At an open house on March 5,  1996,  EPA presented a
Supplemental Proposed Plan for OU2 and the "Original
Responsiveness Summary."  The Supplemental Proposed Plan for OU2
eliminated the off-site incineration component  of the original
May 1995 Proposed Plan, included capping in-place soils  having
dioxin contamination between 5 to 50 ppb, and proposed on-site
landfilling of soil contaminated with  dioxin in excess of 50 ppb.
Under this scenario none of the southern portion of the  site
would have been available for future development.  The community
strongly objected to the Supplemental  Proposed  Plan.

     As a result of revisions to the initial Proposed Plan,  some
of the following responses take into account EPA's preferred
alternative at that time.  Therefore,  some of the responses  will
indicate that capping dioxin contaminated soils in-place is
appropriate.  These comments reflect the EPA thinking at that
time and are included as part of the administrative record.
Nonetheless, the remedy presented in this Record of Decision for
the soils media is excavation of 5 ppb and above dioxin
contaminated soils and on-site disposal  in a RCRA Subtitle C
Landfill, not capping.

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                  ORIGINAL RESPONSIVENESS  SUMMARY

      This  "Original Responsiveness  Summary" has been prepared to
 provide  written responses to  comments  received at the public
 meeting  and during the public comment  period  for the Proposed
 Plan  of  Action for Operable Unit  2  media  at the Vertac Superfund
 Site.

      An  informal open  house was held in Jacksonville on May 25,
 1995, to discuss EPA's proposed plan of action for remediating
 the contaminated soils at the Vertac site.  A public meeting was
 held  at  the Jacksonville  Civic Center  on  June 15, 1995 to further
 discuss  the EPA's cleanup proposal  and to formally accept
 comments on the plan.   The transcript  of  this meeting is included
 in the Administrative  Record.  The  comment period ran from May
 26, 1995 to August 11,  1995.

     Written comments  on  the  proposed  plan were submitted by the
Arkansas Department of  Pollution Control  and Ecology (ADPC&E),
Hercules, Incorporated, State  Senator  Bill Gwatney,  the Concerned
Citizens Coalition, the En Lronmental  Compliance Coalition, the
Jacksonville Chamber of Commerce, the  Jacksonville Commerce
Corporation, City  of Jacksonville Office  of Economic Development,
the Jacksonville Serotoma Club, the Jacksonville Lions Club,  the
Arkansas Peace Center,  Vietnam Veterans of America,  the
Environmental Health Association of Arkansas,  Jacksonville
Mothers  and Children's Defense Fund, and  numerous concerned
citizens.  ADPC&E  also submitted additional comments on the draft
ROD which can be found in Appendix C.

     As will be explained in greater detail within the
Supplemental Proposed Plan, which modifies the Proposed Plan upon
which the comments below were submitted,  since the May 26, 1995,
issuance to the public of the  initial  Proposed Plan for OU 2,  the
EPA announced a series of administrative  reforms to the Superfund
Program  on October 3,  1995, to be effective immediately.   The
October  3,  1995, administrative reforms that EPA followed in
reevaluating the preferred remedy it had  proposed for OU 2 were
those intended to  control remedy costs and to promote the cost-
effectiveness of remedies  for  Superfund sites, and that directed
EPA to base  remedy decisions  on practical future land usage and
exposure pathways  scenarios for a given Superfund site.  In
addition, EPA's  reevaluation  of the preferred remedy for OU 2 of
the Vertac  Site  has been  thoroughly reviewed and approved by EPA
Headquarters Dioxin Review Board to ensure its consistency with
EPA's decisions  concerning dioxin-contaminated soils at
 industrial  sites elsewhere in the county. Finally, EPA has
requested that  the Agency for Toxic Substances Disease Registry
 (ATSDR)  with its revised  approach for  OU2, and ATSDR has  informed
EPA that this  approach is protective of the human health  and  the
environment.

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     Due to EPA's revision of its initial Proposed Plan for OU 2,
the responses to some of the comments will take into account
EPA's revised approach for the remediation of OU 2.
Arkansas Department of Pollution Control and Ecology comments

1.   Comment:  For years an earthen central ditch had been the
               pathway for transportation/migration of off-
               specification materials.  During 1984-1985 Vertac
               lined the bottom of the central ditch with
               concrete.  In 1986 Vertac gunnited the slopes of
               the ditch.

               The survey measurements and the persistent seepage
               of groundwater into the central ditch indicates
               that the base of the central ditch is below the
               adjacent ground water level.  Thus,  contaminated
               soil/sludge beneath the lined concrete is a major
               and continuous source of ground water
               contamination.

               Any remedial action which leaves the highly
               contaminated soil/sludge beneath the lined
               concrete at the central ditch does not provide
               adequate protection of the environment.   ADPC&E
               recommends inclusion of the soil/sludge beneath
               the central ditch as part of the soil remedy.

     Response:  EPA acknowledges that the central ditch at the
               Vertac site was used an unlined disposal conduit
               for many years.  However, information presented
               during the remedial investigat'  ~i at the site
               indicates that bedrock is very near the surface in
               this location and as such very little soil is
               thought to be present in that area.   Contaminants
               in this area would most likely be present in
               fractures in the bedrock itself.

               Under EPA's selected remedy for the Vertac site,
               the southern 100 acres  (i.e., the area that
               contains the central ditch) will be fenced and
               access will be restricted to future site workers.
               Soils within the restricted area that have dioxin
               concentrations greater  than 5 ppb and less than  50
               ppb will be covered with 1 foot  of clean soil to
               prevent direct exposure by site  workers.    Deed
               notices and appropriate restrictions will  also be
               placed on this portion  of the site to prevent
               unauthorized  excavation into the soil cap.

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           Ground water contamination  at  the  site  is  being
           addressed by EPA  in  a  separate Record of Decision.

 Comment:   Soils  beneath some of  the tank foundations are
           heavily contaminated.  ADPC&E  does not  believe
           sealing foundations  where persistent staining
           exists is a  proper method of treatment.  The
           contaminated soils beneath  tank foundations,
           especially foundations that consist of  ped: '.^ls,
           should be remediated.

 Response:  EPA agrees that soils below many of the old
           process  tank foundations may be heavily
           contaminated.  However, because EPA has determined
           that the southern 100 acres of site has little
           potential  for commercial redevelopment, access to
           this area  will be restricted for the foresseable
           future.  As  such, site workers will be performing
           their daily  activities (mainly ground water
          monitoring and treatment and site maintenance
           activities)  under an authorized health and safety
          plan that will ensure their protection.  Because
          building foundations, curbed areas, and other
          paved surfaces will remain in place,  there is
           little potential for direct exposure to
          contaminants below these structures.   Surface
          contamination on foundations will be removed
          through scarification and hydroblasting, and any
          areas that have persistent staining will be
          sealed.

Comment:  EPA has  indicated its desire to remediate the
          eastern half of the central process "^ea for
           future commercial/industrial usage.  However,
          under EPA's  preferred remedy the foundations would
          be left  intact.  Beneath some of those  foundations
          there could  exist highly contaminated soil.  So,
           if and when  industrialization of this section of
           the site becomes a reality, construction
           activities could bring contaminated soil to the
           surface.   Even with a comprehensive deed
           restriction,  it would be difficult to monitor the
           integrity  of every foundation.  Therefore, the
           above  concern should be addressed  at this  time.

Response:  EPA now  has  determined that access for  most of the
           southern 100 acres of the site will remained
           restricted.   However,  a 150 foot wide buffer  zone
           along  Marshall Road  will be cleaned to
           commercial/industrial  levels and as such could  be
           developed for commercial/industrial purposes.

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                There  are  no  building  foundations within the
                buffer zone along Marshall Road that will require
                remediation.   See Figure  13  in the ROD.

 4.   Comment:   Since  EPA's preferred  remedy is not specifically
                listed in  the feasibility study (FS), please
                explain the nature of  remedial activities once
                excavation of the contaminated soil is completed
                (i.e..  backfill!;*^, grading,  placement of topsoil,
                vegetative cover, etc.).

     Response:  EPA's  selected remedy  for site soils is
                Alternative S-2 in the FS with designated changes
                in action  levels.  Soils  with dioxin
                concentrations exceeding  the  action level of 5
                ppb, but less  than 50  ppb will be capped in place.
                Capping will  involve covering the contaminated
                surface soil with a 6  inch layer of compacted
                soil, topped by a 6 inch  layer of topsoil,  and
                revegetating the cap.  Excavated areas would be
                backfilled and compacted  with clean soil,
                including  6 inches of  topsoil (to return areas to
               pre-excavation grade),  and revegetated.   Some
                surface drainage modifications may be used to
               control runon  and runoff,  thereby minimizing the
               potential for the deterioration of the soil cap.

              Concerned Citizens Coalition Comments

     The Concerned Citizens Coalition is the group of
Jacksonville citizens that has undertaken the responsibility of
administrating the Technical Assistance Grant (TAG)  for the
Vertac, Jacksonville,  and Rogers Road landfill Superfund sites.
As part of that responsibility, the group felt compelled to
carefully evaluate the FS and EPA's Proposed Plan of action for
the Vertac soil remediation,  and as such, has developed several
specific recommendations  to  EPA's proposal,  which they designate
as the "Jacksonville Plan."   EPA received numerous letters in
support of the  "Jacksonville Plan," some of  those included
letters from such parties as the State Senator, the Jacksonville
Chamber of Commerce,  and  the Jacksonville Serotoma Club.
     The Major elements of the  "Jacksonville Plan"  are  as
follows:

5.   Comment:  The on-site landfill  should be  constructed  on the
               extreme northwest section of the site.   The base
               dimensions shall not  exceed 500 feet by  500 feet,
               and the vertical height shall not exceed 25 feet.
               In order to maintain  the proposed landfill

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          dimensions, the following should be considered:
          1)  Ship wood debris from the demolition
          activities, salt and ash, bagged soils from off-
          site residential areas, and other off-site soils
          to an off-site permitted facility for treatment
          and disposal; 2) decontaminate and recycle all
          steel from non-product piping and vessels
          structural steel (I-beams), steel doors, sheet
          metal, etc.; 3) place product piping and vessels
          into the landfill, and; 4) place concrete,
          asphalt, bricks, and cinder blocks into the
          landfill (crush prior to placement to minimize
          long axis to 18 inches).

Response: Based on the current estimated volume of material
          to be placed into the on-site landfill,  the
          dimensions should be very close to those presented
          by the Concerned Citizens Coalition.   However, the
          exact dimensions will be established when the
          design is finalized over the next few months.   The
          ROD for Oper,." le Unit 1 (the old process plant)
          called for recycling of non-contaminated or
          lightly contaminated material when possible.
          Recycling,  however,  is not desirable  when more
          waste is generated during decontamination
          activities than is generated from efficient
          disposal practices.   Specific details on recycling
          of materials will  be developed during the remedial
          design.

          Compaction of demolition debris,  concrete,  metal,
          wood,  etc,  will be an integral component of the
          landfill construction.   Void spaces within the
          landfill will be minimized to ensure  the integrity
          of the structure.

          Wood debris,  bagged soils and other off-site soils
          must be remediated as specified in EPA Records of
          Decision for the site.   These materials have been
          designated to be placed into the on-site landfill.
          At present, no decision has been made regarding
          the disposal of the incinerator salt and ash.  EPA
          is concurrently issuing for comment an Engineering
          Evaluation Cost Analysis (EE/CA) that outlines
          EPA's disposal preference for these materials.
          That preference involves the on-site in the RCRA
          Subtitle C landfill of the incinerator ash, salts,
          and pallets on which the drummed ash and salts had
          been stored.

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8.
9,
 Consent:   The landfill leachate handling  system should be
           protective of ground water and  surface water and
           consist of a temporary holding  tank  coupled  to a
           pump station with  a  direct pipeline  to the on-site
           water treatment  system.

 Response:  The final  design for the on-site RCRA Subtitle C
           landfill has not been completed at this time.
           However, because most of the material that will be
           placed into the  on-site landfill will be
           construction debris  and soil, very little leachate
           is  expected to be  generated or  collected from the
           disposal unit.   Any  leachate collected from  the
           landfill would be  processed through the existing
           on-site  ground water  treatment  system.

Comment:   Roads  to the new landfill  should be constructed of
           concrete or asphalt to minimize dust  and sediment
           migration.

Response:  EPA agrees  that  dust  suppression will  be an
           important aspect of soils remediation  at the site.
           The specific  engineering controls that will be
           used during  soils remediation will be developed
           during the  remedial design phase of the cleanup.
           It is  likely that hard surface roads will be used
           to allow access  to the landfill during varied
          weather conditions.

Comment:  A large drainage swale or french drain should be
          placed inside the fenced site area to control
           surface water runoff.

Response:  Surface runoff from the southern portion of the
           site is currently directed through the  existing
           sump/water  treatment  system at the site, i.e., the
           "first flush," or  surface water that  passes over
           the site (which  is typically the most
           contaminated) is collected in the on-site sump
           system and  is processed through the on-site  carbon
           treatment system prior to  discharge.   Additional
           drainage controls  will be  implemented as part of
           the OU2  ROD that will minimize  surface water runon
           and runoff  from  areas that have been  capped.

Comment:   Establish  a 75 foot  unobstructed buffer zone
           outside  the fenced portion of the site. Outside
           the buffer zone  establish  a 75  foot  wide
           vegetative barrier that will serve to obscure the
           site  from  the community.

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Response: The selected remedy will require that a 150 foot
          buffer zone be established for the southern
          portion of the site along Marshall Road.  A visual
          barrier will also be established so as to obscure
          as effectively as possible the site from the
          surrounding community to the east and south.
10.  Comment
          The site fence line for the southern portion of
          the site should be approximately 225 fact ^.~~^ of
          Rocky Branch Creek, extending in a north-
          northeast direction to the juncture of the two
          existing site fences running east-west.

Response: EPA now believes that the future landuse scenario
          for the southern 100 acres of the site should
          involve long-term restricted access, rather than
          extensive potential future commercial/ industrial
          redevelopment.

          In the proposed plan,  EPA had origionally
          envisioned that approximately 50 percent of the
          southern 100 acres of  the site would eventually be
          returned to commercial/ industrial use.   However,
          after re-evaluating the long-term operational and
          maintenance requirements for this area of the site
          (i.e. ,  maintaining the caps on the existing site
          burial areas, the RCRA Subtitle-C landfill,  and
          operation and maintenance of the ground water
          treatment system) ,  EPA believes that these
          operations will substantially reduce the chance
          for extensive future redevelopment opportunities
          on the southern 100 acres.   Thus,  the site fence
          along the eastern bo.rder of the site -'ill be
          located approximately  150 feet west or Marshall
          Road generally  running in a north-south direction.
11.  Coament:
     Response:
          All buildings and structures,  including concrete
          and asphalt pavements,  within the existing
          Hercules security area should be demolished and
          disposed of properly.

          The ROD for Operable Unit 1 requires that all
          above ground structures at the southern portion of
          the site, including buildings and plant equipment,
          be demolished as a part of site remediation.  In
          addition, most of the above ground structures in
          the northern portion of the site will also be
          removed except for the old munitions bunkers,
          which were never a part of herbicide operations at
          the site, and possibly the EPA-constructed pole
          barns.  Some interest has been expressed that
                           8

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12.  Comment:
           these  structures may  be useful  for  future
           commercial  operations.  EPA will  ensure  that  these
           structures  were decontaminated  and  clean if left
           in place.

           Because access to the southern  portion of the site
           will remain restricted, building  foundations,
           curbed areas, and roads will remain in place  after
           cleaning.

           Hercules should construct permanent office and
           equipment storage facilities, not temporary
           structures.
     Response: Construction details involving office space, site
               maintenance facilities, and the waste water
               treatment plant will be addressed during the
               remedial design phase of the cleanup.  These
               issues are generally not specified in a ROD.
13.  Comment:
          Hercules should clean all soils to an acceptable
          action level of 5 ppb within the security
          perimeter.  All areas outside the security
          perimeter shall be cleaned to 1 ppb 2,3,7,8-TCDD
          toxic equivalent quotients (TEQs).

Response: Since the May 26, 1995, issuance to the public of
          the initial Proposed Plan for OU 2, the EPA
          announced a series of administrative reforms to
          the Superfund Program on October 3, 1995, to be
          effective immediately.  The October 3, 1995,
          administrative reforms that EPA followed in
          reevaluating the preferred remedy it had proposed
          for OU 2 were those intended to control remedy
          costs and to promote the cost-effectiveness of
          remedies for Superfund sites, and that directed
          EPA to base remedy decisions on practical future
          land usage and exposure pathways scenarios for a
          given Superfund site.  In addition, EPA's
          reevaluation of the preferred remedy for OU 2 of
          the Vertac Site has been thoroughly reviewed and
          approved by EPA Headquarters Dioxin Review Board
          co ensure its consistency with EPA's decisions
          concerning dioxin-contaminated soils at  industrial
          sites elsewhere  in the county.   Finally, EPA has
          requested that the Agency for Toxic Substances
          Disease Registry  (ATSDR) with its  revised approach
          for OU2, and ATSDR has informed  EPA that this
          approach  is protective of the human health  and  the
          environment.

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14.  Comment:
               Therefore, EPA has concluded that capping  in place
               soils with dioxin concentrations exceeding the
               action  level of 5 ppb, but less than 50 ppb, will
               be protective of human health and the environment
               and cost effective.  Capping will involve  covering
               the contaminated surface soil with a 6 inch layer
               of compacted soil, topped by a 6 inch layer of
               topsoil, and revegetating the cap.  Excavated
               areas would be backfilled and compacted with clean
               soil, including 6 inches of topsoil (to return
               areas to pre-excavation grade), and revegetated.
               Some surface drrinage modifications may be used to
               control runon and runoff, thereby minimizing the
               potential for the deterioration of the soil cap.
               Soils with dioxin concentrations in excess of 50
               ppb will be excavated and consolidated within the
               on-site RCRA Subtitle C landfill.

               All areas east of the Hercules security perimeter
               shall be reclaimed to original grade with a slope
               not to excei.~ 2 feet per 100 feet.
     Response: Details involving the extent and location of
               excavation, capping, and grading will be developed
               during the remedial design phase of the cleanup.
15.  Comment:
               No contaminated soils shall be used as filler for
               restoring excavated areas to grade.
     Response: EPA agrees.  Only clean soil will be used for
               backfilling purposes.

                       Citizens' comments

     The citizens of Jacksonville showed a decided interest in
EPAs proposal to remediate soils <*t tue Vertac site.  Over 300
citizens responded either individually or by signing various
petitions stating their cleanup preferences for the site.
Similar questions have been grouped together in order to more
fully respond to all the issues raised by the Jacksonville
community.
16.  Content:
               Locate the landfill to the NW adjacent to or on
               the other side of the present landfills.
     Response: Over the past several months EPA has been working
               with ADPC&E and Hercules to develop an  alternate
               location for the on-site RCRA  Subtitle  C landfill.
               In order to be responsive to the community
               interest on this issue, the proposed location for
               the new landfill will be on the west side of Rocky
                                10

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17.  Comment
Branch Creek, roughly at the midpoint from north
to south.  EPA, however, is still working out a
potential conflict situation with the U.S. Air
Force that is currently planning on upgrading
their sanitary sewer line which crosses the Vertac
property near the proposed landfill location.
Currently, it appears that the two projects can
proceed as planned if closely coordinated.

Reduce the height of the landfill, transport the
maximum amount of waste from the site,  and
landfill only what cannot be transported.   The
maximum height of the landfill should not exceed
25 feet.
     Response:  There are two primary alternatives that can be
               implemented in order to reduce the height of the
               RCRA Subtitle C landfill that will be constructed
               at the site:   1)  Make the footprint of the
               landfill  larger,  thereby lowering  the height of
               the structure,  or;  2),  put less material into the
               landfill.   Because  of the overwhelming response  by
               the community to locate the landfill at the back
               portion of the site,  the ability to increase the
               size of the landfill footprint is  limited.   So,  to
               minimize  the  height of the landfill,  EPA agrees
               that less material  should be placed into the unit.
               However,  off-site transportation and treatment of
               soils from the Vertac site is a cost prohibitive
               operation.   Estimates from the OU2 FS show the
               cost to excavate site soils and transport them to
               an off-site incineration facility  to be
               approximately $6,000 per ton.    "f-site treatment
               of dioxin-contaminated soils above the 50 ppb
               action level  would  exceed $25,000,000.   EPA will
               now require that most of the contaminated soils  at
               the southern portion of the site to be capped in
               place.  Access in this area will be restricted to
               on-site maintenance workers, and by capping all
               dioxin-contaminated soils below 50 ppb, workers
               will not  be required to wear protective clothing
               to conduct their daily site maintenance
               activities.  EPA will, however, require the most
               contaminated areas  of the site to  be excavated and
               landfilled.  This is a change from landfilling
               approximately 17,000 cubic yards to about 4,200
               cubic yards.  Capping is a cost effective means of
               minimizing any potential threat to human health or
               the environment, while reducing the size of the
               on-site landfill.  EPA normally does not include
               actual specifications for remedial alternatives  in
                                11

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18.  Comment:
          a ROD.  Those issues will be addressed during
          remedial design.

          Restore the original buffer zone between the
          residences and the plant site, move the fence and
          gates to the original location, clean the soil on
          the south and east side to 1 ppb.
Response: It will be impossible to move the fence
          at the southern side of the site to its original
          location, because of the existence of the French
          drain leachate collection system which is a part
          of the long term remediation effort of the site.
          The French drain was installed in 1986, under a
          court-ordered remedy, to intercept ground water
          contamination that could potentially pass beyond
          the site boundary.  Pursuant to the 1986 Court-
          orderd remedy, Hercules is required to maintain
          the French drain system for a minimum of 20
          additional years.   Under this remedy EPA will
          require trees to be planted along the perimeter of
          the site where access will be restricted so as to
          provide a visual buffer to residents that live
          along the southern and eastern margins of the
          site.   In addition,  EPA will require that the
          southern gate be closed and new fencing be
          installed that will prevent future access to site
          from that area.

          In response to the requested 1 ppb action level,
          as discussed in Response Number 15,  EPA has
          established a 1 ppb action level for dioxin for
          all areas of the Vertac site that will be outside
          of the restricted access portion of w~a site.
          This will include a strip along Marshall Road and
          the northern 100 acres of the site which is slated
          to be returned to a  commercial/ industrial
          development.  The area of the site along the
          southern fence is currently at or below the 1 ppb
          action level for dioxins.  All areas within the
          restricted access southern portion of the site
          will be cleaned to a 5 ppb dioxin action level.
19.  CoBuumt:
          The heart of the plant site should be cleaned so
          that all grids with more than 5 ppb dioxin will be
          excavated and cleaned.
R«spons«: See response to Comments 15, 18 and 19.
                           12

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 2 0.  Comment:
          Place warning signs at inside perimeter of buffer
          zone.
     Response: Appropriate  signage will be required as part of
               this remedy.  Areas of the site that will have
               restricted access will be so designated.
2l.  Comment:
          Dress up green area and maintain in a well-groomed
          condition.
     Response: Hercules will be required to maintain all
               restricted access portions of the site.  This will
               include such activities as landscaping and mowing
               so as not to present a public nuisance.

     The following nine comments are of a similar theme and are
listed separately but responded to as a whole.
22,
Comment:
23,
Comment:
24,
 Comment:
25.
26,
27,
Comment:
Comment:
Comment:
28.  Comment:
I want to see you give us a generous buffer zone
between the homes and the plant site.  I would
ultimately like to see the whole thing taken away
and a park put on it,

Move it and move it all.  This is a horrible
situation for Jacksonville and unsafe.  This
should be EPA's job to see that this is all
cleaned up.  Please don't leave us with this mess
and the problems that go with it.

I would like to express my hope that the Vertac
site be returned to its original use as an
industrial site.  The end use of this property,
including along Marshall Road is of the utmost
importance to Jacksonville.  I support an
effective, expeditious cleanup, such as
recommended by EPA.

I feel that the site should be cleaned up totally
so that it would be safe for children to be on the
grounds.

Return the site to the very best condition
possible.

Clean the northern portion of  the  site to
commercial standards or  for use  as a city park.
The southern portion of  the site should  be  cleaned
to industrial  standards.

All necessary  action should be taken to  ensure
that the Vertac site is  cleaned  up to the point
                                13

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29.  Comment:
30.  Comment
           that  the  site can be used  for commercial
           development, city park, or residential
           development.

           We have lived under the stigma of Vertac for so
           long  that regardless of how long it takes, we want
           the site  cleaned up totally.  This location should
           be suitable for a park for children when cleanup
           is completed.

           We encourage the restoration of the site to its
           original  condition prior to development by
           Hercules  Chemical Company  and its predecessors.
           That would include:  A) Removal of all structures;
           B) removal of all buried wastes; C) removal of all
           contaminated soils, and D)  ; restoration of ground
          water to  background standards.  We would like to
          see in the future a site that could be used for
          any activity including development and use as
          parks, residences,  commercial establishments or
          industrial '"cilities.

Response: EPA agrees that cleanup of the Vertac site is
          necessary.  Under the proposed remedy for the
          Vertac site soils,  approximately 50 percent of the
          property will be available for
          commercial/ industrial redevelopment.   This is due
          to the facts that the southern portion of the site
          currently contains landfills and will contain the
          RCRA Subtitle C landfill,  which will be
          constructed to contain site equipment, debris and
          soils.  In addition,  that portion of the site
          contains ground water monitoring and treatment
          facilities,  whioh will renain in place due to the
          necessity for conducting long term ground water
          remediation and monitoring.  Therefore,  most of
          the southern portion of the site will remain under
          restricted access.   However, a north-south strip
          of land along Marshall Road (approximately 150
          feet wide) will be cleaned so as to allow for
          commercial development in that area.

          As previously stated in response to Comment 11, a
          buffer zone will be in place for the  southern and
          eastern portions of the site.  These  areas are or
          will be cleaned up to 1 ppb for dioxin, and visual
          vegetative barriers will be installed.  Because of
          the extensive contamination present at the old
          process plant area of the  site, cleanup to a level
           that would permit the development of  a park would
           be cost-  prohibitive.  EPA, when developing
                           14

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               appropriate remedies for a site, must also
               consider the past use of that property.  The
               Vertac property has been in commercial use for
               over  60 years, and as such, EPA's remedy for the
               site  must be consistent with its past use.
               Finally, EPA's mandate under the Superfund law is
               to provide long term solutions to hazardous
               substance contamination problems by abating
               conditions that pose imminent and substantial
               endangerments to the human health and the
               environment.  However,  under the Superfund law,
               EPA is prohibited from substantially improving a
               property beyond its pre-contamination condition.
               Because the proposed remedy for OU 2 will be
               protective of the human health and environment and
               will allow a substantial portion of the site to
               return to industrial usage, EPA will meet its
               mandate while not improving the property beyond
               its existing industrial usage,  which would be the
               case were it to accomplish a cleanup goal that
               would permit residential uses of the property.

31.  Comment:  I believe it is in the  best long term interest of
               the EPA,  the City of Jacksonville,  and the State
               of Arkansas to not bury any more wastes at the
               site.   There are sufficient off-site landfills
               available able to receive these wastes.

     Response: One of the issues that  EPA had to consider when
               evaluating disposal options for dioxin
               contaminated soils at Vertac was the "dioxin rule"
               which states that if dioxin wastes are taken off-
               site then they must be  treated  'a the Best
               Demonstrated Available  Technology (BOAT)  prior to
               disposal.   BOAT requires that a treated F-02X
               waste (dioxin-containing waste) be reduced to less
               than 1 ppb TCDD as determined by the toxicity
               characteristic leaching procedure (TCLP)  found at
               40 CFR Part 261, Appendix II, prior to land
               disposal in a RCRA permitted landfill.  Therefore,
               any soil that is transported off-site would first
               have to be incinerated (at a cost of approximately
               $4,000 per ton) and then the residuals would have
               to be land disposed in a RCRA Subtitle C landfill
               per RCRA regulations.  Thus, the cost for off-site
               disposal of dioxin wastes is extremely high.  On
               the other hand, on-site disposal of dioxin-
               contaminated soils may be land disposed  in a RCRA
               Subtitle C landfill without triggering the 1 ppb
               land  ban requirement if done within a contiguous
               "area of contamination"  (AOC).  According to EPA


                                15

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               guidance  (OSWER Directive 9347.3 05FS),  "for the
               land disposal restrictions  (LDRs) to be  applicable
               to a CERCLA response, the act must first
               constitute placement of a restricted hazardous
               waste."  Therefore, it must first be determined
               whether consolidation activities considered or
               contemplated at the site constitute placement, and
               if a RCRA hazardous waste is involved.   To assist
               in defining when placement does and does no*- ^ccur
               for CERCLA actions involving on-site disposal of
               wastes, EPA uses the concept of areas of
               contamination (AOCs) which are equivalent to RCRA
               units, for the purpose determining the
               applicability of RCRA's land disposal restrictions
               found at 40 CFR Part 268.  An AOC is delineated by
               the areal extent of contiguous contamination.
               Placement does not occur when wastes are left in
               place, or moved within an AOC.   Specifically,
               "placement does not occur when the wastes are
               consolidated within the AOC."  See preamble to the
               National Contingency Plan (NCP),  55 Federal
               Register 8759 - 8760,  March 8,  1990.

               In addition,  minimum technology requirements are
               also not required within the AOC but may be
               relevant and appropriate requirements for such a
               CERCLA action.   If materials are treated on-site
               within the AOC and then redeposited within the AOC
               such as within a landfill,  then placement has
               occurred and land disposal restrictions would
               apply.   However,  as noted above,  because the
               proposed on-site landfilling of dioxin-
               contaminated soil and debris will occur entirely
               within the Vertac AOC,  but without p^or
               treatment,  placement will not occur for purposes
               of applicability of the RCRA land disposal
               restrictions.

32.  Coament:  it is in the best long term interest to exhume the
               existing wastes.  I realize there are existing
               court decisions and RODs that must be overcome in
               order for this to occur.  I believe that it can be
               done, and shorten the overall site cleanup,
               including that for groundwater.

     Response: In 1984 EPA challenged the court-ordered plan for
               disposal of waste materials in the on-site burial
               areas at Vertac with no success.  See Order of the
               U.S. District Court for the Eastern District of
               Arkansas, Western Division, in U.S. v. Vertac
               Chemical Corporation and Hercules. Inc.. No. LR-C-


                                16

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               80-109, July 18, 1984.   Because that Order is now
               unappealable, EPA will continue to evaluate the
               effectiveness of the Court-ordered remedy, and
               will respond as appropriate.

33.  Comment:  I believe the dioxin cleanup standard should be
               1-10 ppb.  I do not object to the on-site
               treatment via incineration or tilling of soil for
               exposure to sunlight.

     Response: EPA has established that 5 ppb dioxin cleanup
               standard is appropriate for a
               commercial/industrial future use exposure scenario
               for the Vertac site.  EPA no longer favors
               additional treatment of dioxin-contaminated soils
               at the Vertac site for the following reasons:
               When looking at the Vertac site and each of the
               six operable units as a whole,  it can be seen that
               a substantial amount of treatment,  both on-site
               and off-site, have been employed to address
               principal threats at the site.   Examples of on-
               site treatment include the incineration of
               approximately 29,000 drums (10,000  tons) of
               dioxin-containing organic liquids.   The dioxin
               concentration in these drums was one to several
               orders of magnitude greater than that generally
               found in the Vertac site soils.   In addition,  the
               contents of the abandoned tanks at  the site,  oily
               leachate from the french drain system,  and
               contaminated carbon from ground water treatment
               operation will also be treated by incineration at
               an off-site facility and will exceed approximately
               5,000 additional tons of material.   As such,  a
               significant amount of the dioxin at the site has
               or will be treated during site remediation
               efforts.

34.  Comment:  I object to siting the landfill on clean soil near
               the railroad.  I believe that this area should be
               kept clean for future development.

     Response: EPA received overwhelming response from
               Jacksonville citizens that if an above  ground on-
               site landfill was necessary at the Vertac site,
               that it be placed as far back on the Vertac
               property as possible and that its height be
               restricted to 25 feet or less if possible.  The
               current proposed location for the on-site  landfill
               is responsive to those concerns.  As far as future
               development  in the  proposed  landfill area,  it  is
               true that this area is clean.   However, because  of
                                17

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35,
Comment:
the location of Rocky Branch Creek to the east and
the railroad to the west, access to this area is
extremely limited.

EPA's proposals do not take into account exposure
of children, who are at higher risk and when
factored in make risks unacceptable.
36,
37,
38.
Response: The  future  land use for the Vertac site was
          assumed to  be a commercial/industrial scenario,
          and  is based on the most probable use of the land
          and  current land u?e zoning requirements.  For a
          commercial/industrial type scenario exposure to
          adults is evaluated rather than to children.

Comment:  Alternative disposal methods should be employed,
          not  incineration, either off-site or on-site.

Response: In the proposed remedy for Vertac soils, off-site
          incineration is no longer a component of the
          cleanup.  I--,tead, EPA has proposed employing on-
          site landfilling and on-site capping as
          alternative disposal methods.

Comment:  Health monitoring, health surveys and a disease
          and hazardous waste exposure registry should be a
          priority for the Vertac site.

Response: A health and exposure study was initiated by the
          Arkansas Department of Public Health (ADPH) in
          conjunction with the Agency for Toxic Substances
          Disease Registry (ATSDR)  and the Centers for
          Disease Control (CDC)  over four years ago, and is
          ongoing.  Preliminary results of these studies
          have been presented to the public during a number
          of public meetings over the past several years.
          The commenter is referred to the Arkansas
          Department  of Public Health for information
          concerning the results from those studies.

Comment:  Opening up  any part of the site that does not have
          less than 1 ppb TEQs is irresponsible and contrary
          to EPA's mandate to safeguard health and safety.

Response: Under the proposed remedy for on-site soils, all
          portions of the site that will be available  for
          commercial/industrial development will  be
          remediated  to an action level of 1 ppb  for dioxin.
          Areas that  will remain fenced where access will  be
          restricted  to on-site workers will be remediated
          to 5 ppb for dioxin.
                                18

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39.  Comment:
           Landfill ing is  at best  a  temporary  solution.  The
           existing landfills have breached  the  French drain
           and there is some evidence that the ground water
           at the site is  contaminated.
Response:  EPA  currently has  no data  from Vertac ground water
           monitoring  program that would suggest that the
           French drain leachate collection system is not
           functioning as designed.   EPA does, however,
           acknowledge that the ground water under the Vertac
           site is heavily contaminated with site compounds.
           The  results of the ground  water investigation at
           Vertac can  be found in the OU2 Phase 1 and Phase 2
           Remedial Investigation Reports.  Ground water
           remediation will be addressed as part of the
           Record of Decision for Operable Unit 3.  EPA
           expects to  release a Proposed Plan to discuss
           potential ground water remediation options within
           the  next several months.
40.  Comment:
          Construction of a landfill will allow more
          airborne particulates and fugitive emissions.
Response: The construction of the on-site landfill is
          required as a part of the Record of Decision for
          Operable Unit 1, where all building debris and
          equipment from the demolition of the plant will be
          disposed in the on-site landfill.  Appropriate
          dust suppression measures will be employed and
          monitoring will be conducted to ensure the safety
          of workers and residents living near the site.  As
          a part of the proposed remedy for Operable Unit 2
          (Soils) , EPA is now requiring   r,uch reduced
          volume of soil to be placed into the on-site
          landfill which should substantially reduce any
          issues concerning fugitive emissions from soil
          excavation operations.
41.  Comment:
          Establish a laboratory, testing and research
          facility on the Vertac site for the future
          evaluation of non-thermal dioxin destruction
          technologies .

Response: Many  lawsuits have  been filed  over the  past
          several years concerning the potential  for
          emissions from on-site remedial operations  to
          impact the  local  community.  EPA  is curious why
          the commenter would be interested in  EPA setting
          up an experimental  testing  facility to  work on
          dioxins near a residential  community.  Little is
          known about the potential emissions  from many of
                           19

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                the  new and  untested  technologies.   Such a testing
                facility would most likely have to be  in place for
                many years to determine the effectiveness of new
                treatment technologies.   EPA does not  favor such a
                proposition  for this  site.

       Arkansas Peace  Center, Vietnam veterans of America,
          Environmental Health Association of Arkansas/
        Jacksonville Mothers and Children's Defense Fund,
          and the Environmental Compliance Organisation
                             Comments
42.  Comment:
43,
          The failure to characterize all dioxin and furan
          congeners, and to include analyses-supported toxic
          equivalency quotients  (TEQs) into the generation
          of remedial goals (RGs) is seriously problematic,
          as is the failure of the risk assessment to
          provide calculations for all possible exposure
          scenarios.  Therefore, selection of remedial
          alternatives should be deferred until adequate
          analytical data in regard to dioxins and furans
          are available.

Response: EPA agrees that it is important to evaluate all
          dioxin and furan congeners when addressing the
          risk from exposure to site soils.   Because these
          data were not available for most of the sampling
          that was conducted for the site during the
          remedial investigation, EPA is requiring that all
          soil remediation be conducted with respect to
          dioxin and furans as 2,3,7,8-TCDD toxicity
          equivalents (TEQs).   That is to say, for each soil
          grid remediated at the site, the average
          dioxin/furan concentration shall not =xceed the
          action level as for TCDD and TCDFs as TEQs.

Comment:  There is a concern regarding the absence in all
          data obtained for review of an attempt to
          calculate soil remedial goals that would be
          protective of the extremely aggressive ground
          water Maximum Contaminant Limit (MCLs) of 30 parts
          per trillion  (TEQ) for dioxin established by EPA
          and the even lower TEQ thought to be protective of
          surface water.

Response: Remediation of ground water at the Vertac site
          will be addressed as part of the Operable Unit 3
          ROD.  In general, the ground water  situation at
          the Vertac site  is extremely complex, due to the
          presence of dense nonaqueous phase  liquids
          (DNAPLs) and  questions as to how they move within
                                20

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44.  Comment:
 a tilted,  fractured bedrock environment.   These
 dense phase liquids typically  migrate  down along
 dipping rock strata and are trapped in fractures
 where current remediation technologies have a very
 limited potential  of capturing them.   As  such,
 these DNAPLs will  provide a long term  source for
 dissolved  phase  contamination  at the site.  A
 ground water technical  impracticability waiver
 will  most  likely ^e sought for the  central  process
 plant portion of the site,  and thus attainment of
 MCLs  will  not be required.  One positive point is
 that  ground watrr  (even though highly
 contaminated)  does  not  move quickly under the
 Vertac site.   With  over 40  years of on-site
 operations,  current data suggest that  the ground
 water plume has  not migrated beyond the boundaries
 of the site.   Various forms of ground  water
 containment will be necessary, however, to  ensure
 that  migration of site  contaminants is  controlled
 over  the long term.

 There  are  concerns  that the favored plan of action
 to include  off-site  disposal and on-site
 landfilling  appears  to  be  less than fully
 protective  of human  health  and the  environment,  as
 required by the National Contingency Plan (NCP),
 and does not provide mandated treatment to reduce
 the toxicity, mobility, and/or volume of the
waste.
     Response: EPA disagrees.  Soils within the restricted access
               portion of the site that are highly contaminated
               will be excavated and consolidated into an on-site
               RCRA Subtitle C landfill.  Soils that contain
               lower levels of contaminants will be capped in
               place.  Both excavation and consolidation into a
               RCRA landfill, and capping in place, will
               substantially reduce the mobility of site
               contaminants and will prevent direct exposure
               through dermal contact, inhalation or ingestion by
               future site workers maintaining the restricted
               access area.  Therefore, the proposed remedy is
               fully protective of human health and environment.

               When evaluating the Vertac site and each of the
               six operable units, it can be seen that a
               substantial amount of treatment, both on-site and
               off-site, have been employed to address principal
               threats at the site  (i.e., the most toxic  and
               mobile materials).  Over  15,000 tons of dioxin-
               containing organic liquids and sludges have been
                                21

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45.  comment:
          treated through both on-site and off-site
          incineration.

          We find no discussion of the RCRA land ban
          restrictions on the type of waste contemplated for
          land disposal in this instance as Applicable,
          Relevant and Appropriate Requirements (ARARs).

Response: Page 44 of the Proposed Plan for OU2, and page 12
          of the OU2 Fact Sheet both discuss compliance with
          ARARs and specifically address land ban issues.

          A complete discussion of potential ARARs for each
          disposal option is presented in Sections 2.2, 2.3
          and 2.4 of the OU2 feasibility study.  Pages 2-12
          through 2-16 deal with RCRA disposal and
          specifically with TSD facility requirements,  land
          ban,  and consolidation issues.   See also response
          to Comment 32.
4 e.   Comment:
     Response:
          There is con  rn that there has been limited
          chemical and physical characterization of the
          condition of the existing disposal areas on the
          site.   We can find no documentation of a
          comprehensive ground water monitoring plan,  no
          effort to delineate the  wetlands that appear to
          encroach the northwest disposal area...,  no
          discussion or investigation into the status of
          closed disposal  areas which do  not appear to
          sustain grass or other vegetative cover.

          The north burial area, the south burial area,  the
          Reasor Hill burial area,  above  ground vault (Mt.
          Vertac),  and the cooling water  pond were all
          remediated between 1984  and 1986 as part of a
          Court-ordered remedy. The remedy generally
          involved closing the Vertac plant cooling water
          pond and the equalization basin and consolidation
          of the sediments from these units into an
          excavated area where earlier operators had buried
          drums of waste.   The burial areas were capped and
          a French drain and leachate collection system was
          installed around them.  Ground water monitoring
          wells were also  installed and a ground water
          monitoring program was initiated.

          EPA generally disapproved of the remedial
          approach, but its legal objections were
          overturned.  As  such, these remedies are
          considered to be final,  and further action by EPA
          on this areas is limited unless documentation of
                                22

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           remedy failure  is  found.
           Comment 33.
                                         See also response to
47.  Comment:
           Page  3,  Paragraph  4  of the Proposed Plan states
           that  soil  concentration  levels are based on what
           "will be protective  for  persons reasonably
           expected to be  in  contact with these soils."  This
           statement  fails to note  that EPA health-based
           cleanup  standards  are to be conservative, not
           reasonably protective.   Additionally, this
           rationale  fails to embrace the twin mandate of
           CERCLA to  protect  both human health and the
           environment...  No demonstration has been
           presented  that  the proposed soils remediation
           goals  will provide adequate protection of ground
           water  resources and aquatic environments.  The
           concluding sentence of this paragraph notes
           primarily that  the preferred alternative is cost
           effective.  However, under existing EPA guidance
           cost is not to  be  considered in preference to
           technical considerations, except where the
           difference in cost between to alternatives
           represents a magnitude of order discrepancy.

Response:  EPA believes that a remediation goal for dioxin of
           5 ppb TEQ is protective of human health and the
           environment assuming a commercial/ industrial
           exposure scenario.   See EPA's risk assessment
           dated April 11, 1995, which is part of this
          Administrative Record.  This action level is being
           applied to that portion of the site (southern 100
           acres) where access will remain restricted to
           future site workers and  is conr  ->red to be
           conservative for that exposure scenario.  A 1 ppb
           dioxin action level will be required for all other
           area of the site that will have unrestricted
           commercial access.  While ground water issues are
           not being  addressed in this ROD, they will,
           however, be addressed in the ROD for Operable Unit
           3.  See  also response to Comment 44.
48.  Comment:
          There exists a potential conflict of  interest
          involved with allowing a responsible  party to
          perform a risk assessment that will subsequently
          determine remedial  goals, given  the negative
          economic implications of more extensive,  and more
          protective, remedial work.

Response: EPA allowed Hercules to conduct  the baseline risk
          assessment  and Monte Carlo  risk  modelling for the
          Vertac site.  After review  of these documents and
                           23

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           many discussions  with Hercules  and its  contractors
           on various  assumptions used  in  the risk
           assessments,  EPA  decided  to  conduct its own  risk
           assessment.   Remediation  goals  for Vertac were
           established from  the  EPA  site-specific  risk
           assessment  for Vertac,  and not  on  Hercules'
           product .
49.  Comment:
           EPA's  justification  for choosing 261 ppb an^
           as the cutoff  for off-site remediation appears to
           be cost efficiency.  We do not believe that cost
           is a proper, or controlling, factor in determining
           remedial goals whicn are per statute intended to
           be health-based.

Responsa:  The 261 ppb cleanup number presented in the
           Proposed Plan for OU2 media should not be confused
           with a remedial action goal for the site.  It is
           simply a number where EPA made a determination of
           cost effectiveness for applying two different
           treatment technologies.  The health-based remedial
           action goal for site soils was set a 5 ppb TEQ for
           dioxin.
50.  Comment:
          Page 6, Paragraph 2 of the Proposed Plan gives the
          impression that on-site landfilling, a non-
          permanent, non-destructive alternative that does
          not immobilize, detoxify, or reduce We*sic: volume
          is preferable to on-site treatment, despite the
          SARA-mandated preference for treatments.
Response: See response to Comment 34.
51.  Comment
          We request that EPA provide document a ^on of the
          compliance and regulatory history of the APTUS
          facility.  Full explanation of any permit
          suspensions, administrative orders, or notices of
          deficiencies is also requested.

Response: EPA is no longer proposing to send contaminated
          soil to the APTUS facility for treatment under
          this Record of Decision.  EPA has reevaluated the
          necessity to treat dioxin-contaminated soil at the
          Vertac site and since it is not considered to be a
          principal threat at the site, other disposal
          options have been selected in place of
          incineration.  See also response to Comment 34.
52.  Comment:
          We are uncomfortable with  the  assumption that
          since unsampled  areas  of the site are downgradient
          from areas  of  relatively low contamination,  that
                           24

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           no contamination is probable in those  areas.
           More and comprehensive characterization  is
           required and is  a prerequisite  to  critical
           remedial determinations.

Response:  EPA disagrees.   When examining  the soil
           contaminant  data that  were collected from over 460
           different collection grids at the  Vertac site,
           patterns of  contaminant distribution become
           readily  apparent.   Site contamination  is related
           to specific  process operations  at  specific site
           locations and is also  related to past  site
           disposal activities.
53.  Comment
          Page 15, Bullet 3 of the Proposed Plan identifies
          porous bedding media as a potential problem, but
          does not elaborate on potential contaminant
          migration, corrective action, or sampling effort
          to fully characterize the concern.

Response: EPA has no data that show whether porous bedding
          media was actually used at the site around
          underground conduits, i.e. ,  no plans or drawings
          are available from early construction activities.
          However, EPA has conservatively assumed that
          porous bedding media may be present, and as such,
          the proposed remedy will require that cuttoff
          barriers be installed at specific locations along
          these conduits to prevent any potential shallow
          ground water flow along these lines.
54.  Comment:
          At page 17, Bullets 1 and 3 of the Proposed Plan,
          EPA notes its goal to minimize cancer risks to
          within the statutory mandate between 1/10,000 and
          1/1,000,000.  This is, however, a very broad range
          of values, and requires an explicit statement of
          the specific level of acceptable risk that EPA has
          adopted for OU2 and the site in general.

Response: EPA's risk modelling for the Vertac site shows
          that a commercial/ industrial worker exposed to
          site soils remediated to 5 ppb dioxin or less will
          be exposed on average to 0.67 ppb dioxin.  The
          risk estimated from the Reasonable Maximum
          Exposure  (RME) method is 1X10"*.  Monte Carlo
          modelling predicts the risk at the upper 95
          percentile  level for a 5 ppb cleanup to be 4X1Q~S.
          Both are within EPA's acceptable exposure risk
          range.  See also in the Administrative Record
          EPA's site  specific risk assessment entitled
          "Evaluation of Surface Soil Cleanup level
                           25

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55.  Comment:
               contaminated with 2,3,7,8-TCDD TEQs at the Vertac,
               Inc. Superfund Site," dated April 11, 1995.

               The proposed fish flesh monitoring program should
               be modified to provide better information
               responsive to on-site conditions.  Specifically,
               sampling should be scheduled for one event prior
               to excavation activities, at the midpoint of
               remedial activities, and a 30 days post-remedial
               confirmation sampling.

     Response: EPA was not proposing to conduct a new fish-
               monitoring program.   Rather,  EPA was explaining
               the results of the existing monitoring program
               that is a requirement of the Off-site ROD issued
               in September 1990.  The existing program is
               considered to be adequate for monitoring
               contaminant concentrations in aquatic organisms in
               Rocky Branch Creek and Bayou Meto.
56.  Comnent:
               At page 22,  Paragraph 2 of the Proposed Plan EPA
               takes the position that because public water is
               available on and around the site,  ground water is
               not a potential pathway for human exposure.   This
               is not necessarily the case in that it is well
               documented that ground water normally discharges
               into proximate surface features.   Therefore,
               contaminated ground water from the site is likely
               to discharge into Rocky Branch Creek which is a
               potential human exposure route through both direct
               contact and the food chain.

     Response:  EPA agrees that potential exposure pathways from
               ground water sources may exist for the Vertac site
               through dermal exposure and incidental ingest ion
               exposures from primarily surface water features.
               EPA's statement in the Proposed Plan was that the
               ground water ingestion pathway (drinking well
               water) was unlikely since Jacksonville is on a
               public water supply.

               Ground water exposure issues are not being
               addressed in the Operable Unit Record of Decision.
               They will, however, be addressed in the ROD for
               Operable Unit 3.
57.  Comment:
               The additional characterization data for all
               congeners for dioxin and furan needs to be
               reflected in recalculated risk assessment values.
               It is absolutely necessary that EPA show the
               actual calculations related to the 20 percent
                                26

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                elevation  in risk when all dioxins and furans are
                considered.

     Response:  See response to Comment 43.
58.  Comment:  Page 24, paragraph 2 of the Proposed Plan states
               that 2,4-D contributed materially to an
               unacceptable hazard index of 4  (1.0 is the
               threshold).  However, no soil remedial goals for
               2,4-D are proposed.

     Response: The commenter is correct.  However, EPA need not
               establish remediation goals for all contaminants
               of concern at the site if such contaminants are
               reduced to below levels of concern during the
               remediation of another contaminant.  Such is the
               case for 2,4-D.  When dioxin is remediated in
               surface soils at the site below the specified
               action level, 2,4-D concentrations will also be
               well below a health based exposure levels.

                 Hercules Incorporated Comments

59.  Comment:  Although the plan acknowledges the existence of
               the two areas,  it fails to recognize unique area-
               specific conditions when proposing surface  soil
               cleanup criteria, i.e.,  the plan provides for a 5
               ppb dioxin (TEV)  cleanup criterion for surface
               soil for both the restricted and unrestricted
               portions of the site.

     Response: EPA disagrees.   EPA made a conscious decision to
               establish a soil cleanup level   <  the southern
               restricted access portion of the site that  would
               be protective of a site worker, such that
               protective clothing would not be required during
               the conduct of daily activities.  Several reasons
               for this include:  1)  The long term ground water
               remediation efforts and site maintenance efforts
               will be required, and thus individual site workers
               will likely be required to be at the site a normal
               work period; 2) it is difficult to enforce/monitor
               how well health and safety requirements  (i.e.
               personal protective clothing requirements are
               being maintained) over a long term operation, and
               3); the Jacksonville Community  felt that a "no
               moon suits" requirement should  be established for
               the southern part of the site because of the
               nearness to residential neighborhoods and the fact
               that this site will be a part of their community
               for the foreseeable future.
                                27

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 60.  Comment:   The  5  ppb dioxin  surface  soil  cleanup criterion,
                however,  is  unnecessarily stringent  and
                inconsistent with a  past  dioxin  cleanup
                requirement  of  20 ppb used at  another
                commercial/industrial site in  Arkansas,  e.g..  the
                site in Arkwood,  Arkansas,  and at other  sites.

     Response:  EPA  disagrees that a 5 ppb dioxin surface  soil
                cleanup level is  unnecessarily stringent,  ""--
                commenter  failed  to  note  that  EPA's  risk
                assessment did  not consider an exposure to dioxin
                at a concentration of 5 ppb.   Rather,  EPA more
                liberally  looked  ac  the average concentration of
                dioxin that would be present at the  site after
                remediaion of dioxin at 5 ppb  occurred, which  is
                0.67 ppb.  EPA  calculated the  risk from exposure
                to future site workers based on this average
                concentration and  found the risk to be 1X10"*,
               using EPA RME methodology.  A  cancer risk of
                1X104 is the upper limit of the range  (1X10"1 to
                1X10"*)  that EPA considers to be acceptable.  Monte
               Carlo modelling was also used by EPA to predict
               the risk to a future site worker from exposure to
               dioxin after remediaion at a 5 ppb action level,
               the future risk was estimated at 4X10'5.

               A 20 ppb cleanup level for dioxin (which equates
               to a 2  ppb exposure concentration after
               remediation), based on site-specific conditions,
               would result in exposures that are outside of
               EPA's acceptable risk range for both RME (2.7X10^*)
               and Monte Carlo modelling (1.1X10^*).

               EPA believes that it has appropriately established
               a cleanup level for dioxin at the site that is
               protective of human health.

61.  Content:  The EPA risk assessor incorrectly used EPA default
               risk assessment guidance when selecting the amount
               of skin area exposed to soil for workers wearing
               the clothing described above.  The risk assessor
               used 25 percent as the percent of the total body
                surface exposed every working  day for twenty-five
               years.   This skin  area corresponds to hands, arms,
                face and lower  legs  being continually  exposed.
                For normal work clothing,  i.e..  long  sleeve shirt
                and pants, EPA  risk  assessment guidance  for
                exposure to soil  indicates  that  the  skin exposure
                should be  10 percent (reference  made to  the
                "Dermal Exposure  Assessment: Principals  and
                Applications, Interim Report," U.S.  EPA, 1992)


                                28

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     Response:
          which corresponds to exposure of hands and face.
          This factor alone will effectively reduce the
          estimate of potential risk to future workers by
          about 60 percent for any given soil cleanup
          criterion.

          EPA guidance referenced by the commenter, the
          "Dermal Exposure Assessment: Principles and
          Applications" st^es on pages 8-10 that "for soil
          contact scenarios dermal exposure was expected to
          occur at the hands, legs, arms,  neck,  and head
          (McKone and Layton, 1986) with approximately 26
          percent and 30 percent of the total surface area
          exposed for adults and children,  respectively.
          Less conservative scenarios have limited exposure
          to the arms,  hands, and feet.  The clothing
          scenario presented above suggests that roughly 10
          percent to 25 percent of the skin area may be
          exposed to soil.   Since some studies have
          suggested that exposure can occur under clothing,
          the upper end of this range was  selected for
          deriving defaults.   Thus, applying 25  percent to
          the total body surface area results in defaults
          for adults of 5,000 cm2 and 5,800 cm2.   The
          defaults for  children can be derived by
          multiplying the 50th and 95 percentiles by 0.25
          for the ages  of interest."

          The risk assessor also assumed that future site
          workers would not conduct any of  their activities
          in those portions of the containment area that
          have already  been remediated. Under EPA
          oversight,  40 percent of the containment area has
          been remediated using clean off-site soil and is
          currently contaminant free.  The  EPA risk assessor
          ignores the fact that many of the site activities,
          e.g.,  inspection and maintenance, mowing of capped
          areas,  measuring water levels in monitoring wells,
          etc.,  currently and in the future will occur in
          clean areas.   Hercules believes that the risk
          assessment for the future worker should reflect
          this site information.  If incorporated correctly,
          this factor would reduce the predicted risk to
          future workers by at least 40 percent because
          future site workers are expected a
          disproportionate share of time in clean areas.

Response: The worker exposure area as  defined by Hercules
          includes about 100 acres of  the southern portion
          of the site.  This is considered to be an
          extremely large exposure area.  The exposure for a
62.  Comment:
                                29

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               site worker could be much less than the whole 100
               acre site.  It is currently not known what
               specific activities will be required of future
               site workers and the locations of the site that
               they will be required to conduct their daily
               activities.  In EPA's risk assessment evaluation
               of the soil cleanup level for the southern portion
               of the site, the risk posed by exposure to site
               soils after remediation at a 5 ppb cleanup level
               was approximately 1X10"* based on RME calculations
               and 4X10'5 using Monte Carlo risk estimates.   These
               risk numbers are based on an average exposure of
               0.67 ppb for dioxin, which is the average
               concentration of dioxin for all the southern
               portion of the site that gets remediated.   That is
               not to say that some workers will not be exposed
               to higher concentrations and others to lower
               concentrations,  depending upon the exact location
               where work is conducted at the site.   For example,
               the cleanup scenario requires that any grid at the
               site (each i~ approximately 5,000 sq.  ft.  in size)
               with an average dioxin concentration greater than
               5  ppb be covered with 1 foot of clean soil.   Thus,
               the dioxin concentration at that location is now
               assumed to be half  the detection limit or 0.15
               ppb.   Any grid that has an average dioxin
               concentration of less that 5 ppb,  say 4.9  ppb,
               would be left undisturbed.   For that particular
               case,  the actual exposure point concentration for
               a  worker at that location would be 4.9 ppb and not
               the average of 0.67 ppb for the entire site.   This
               means that the risk associated with exposure to
               this one grid or several adjacent grids if the
               concentrations a^e  similar,  would be higher than
               the average or approximately 8X10"* based on  RME
               and 3X10"* based  on  Monte Carlo,  which are  outside
               of EPA's acceptable risk range.  EPA,  however,
               considers it unreasonable to assume that site
               workers will be exposed only to these grids.
               Rather, EPA believes that site workers will be
               exposed to a range  of dioxin concentrations across
               the site from 4.9 ppb to zero as they conduct
               *:heir daily activities.   Thus, EPA's risk
               assessment reasonably predicts the risks
               associated with future work conducted on the
               southern portion of the site after remediation is
               complete.

63.  Comment:  The EPA risk assessor also failed to consider that
               remedial plans for the site which, although not
               yet finalized, include relocation of most of the


                                30

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               waste water treatment facilities into a clean
               building within the containment area.  Collection
               and treatment of ground water will be the main
               future activity within the containment area.
               Therefore, future worker exposure to site soil
               will be further reduced from that assumed by the
               EPA risk assessor.  Hercules has estimated that
               over one-half of each worker's time in the
               containment area will be spent on operating and
               maintenance activities which will occur within the
               clean building.  This factor should also be
               included in the site risk assessment.

     Response: Recent conversations between EPA and Hercules have
               indicated that the waste water treatment plant may
               not in fact be relocated to a "clean" portion of
               the site.   EPA does not believe it appropriate to
               reevaluate site exposure scenarios based on
               unknowns.   See also response to Comment 64.
64.   Comment:
          Two other inappropriate assumptions or procedures
          were used by the risk assessor that resulted in an
          overly stringent cleanup standard.   One
          inappropriate procedure was the use of a site-
          specific bioavaliability factor of  10 percent that
          was higher than any of the individual results
          determined by the Rutgers University
          bioavailability study for 2,3,7,8-TCDD conducted
          with soils samples from the Vertac  site.  The
          individual results ranged from less than 1 percent
          to less than 9 percent.  An average of the site-
          specific results which had a geometric mean 2.3
          percent more accurately descri>~ - the
          bioavailability of dioxin for Vertac site soil.
          In addition, the risk assessor used a slope factor
          of 156,000 kg-day/mg for 2,3,7,8-TCDD that is
          substantially greater than the slope factor of
          100,000 kg-day/mg which corresponds to the risk-
          specific dose of dioxin (0.01 grams TEV per
          kilogram of body weight results in one additional
          cancer in one million) stated in the plan  (page
          22) .

Response: a) The bioavailability study of 2,3,7,8-TCDD
          conducted by Hercules for Vertac site soils was
          reviewed by EPA and discussed with Hercules
          personnel, Hercules contractors, and the  author  of
          the report on  several  different occasions as  the
          study progressed  and at the conclusion  of the
          study.  EPA found the  study results to  be
          inconclusive concerning whether the  low
                                31

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 measurements  of  bioavailability  were  attributable
 to Vertac soils  or  to  experimental  error.   The
 study failed  to  show proper  expected  responses  in
 the positive  control animals.  It was not  apparent
 from the  authors of the  study that  the experiment
 was designed  or  implemented  to determine a
 reliable,  reproducible bioavailability "factor" to
 be used quantitatively in the manner  proposed by
 Hercules.  Rather,  their study seemed to b«
 directed  more toward establishing whether  dioxin
 in Vertac soils  is  bioavailable  as  determined by
 liver enzyme  responses and other bioassay
 techniques, rather  than  producing specific
 percentages of bioavailability to apply to human
 risk  calculations.  In short, Callow  and Meeker
 (authors  of the  study)  seem to attribute
 qualitative significance to their study, but not
 the quantitative significance which Hercules does.
 Site-specific soil  studies done  at other Superfund
 sites showed a wide degree of variation in
 bioavailability.   For example,  Callow and Meeker
 discussed a Times Beach soils study that showed
 approximately 30 percent bioavailability.   There
was no indication that an attempt was made to
characterize the soils (i.e., sand versus clay or
absorption capacity) to help correlate or explain
differences within Vertac soils or between Vertac
soils and Times Beach or other site soils.   EPA
does not believe that the Hercules bioavailability
study for Vertac site soils was conclusive for the
reasons mentioned above.   However,  EPA gave
Hercules credit for conducting the study and
acknowledges that dioxin absorption from soil is
expected to be less chat absorption ^om corn oil
 (55 percent is often used as the default
bioavailability for dioxin),  thus an absorption
 factor of 10 percent (the upper range of the
 individual results obtained in the Hercules study)
was accepted by EPA and was used in EPA risk
 assessment calculations  for the  site.

 b) The statement by Hercules that M... 0.01 grams
 TEV per kilogram of body weight  results in one
 additional cancer in a million"  was improperly
 cited from EPA's proposed plan.  What EPA  stated
 was that  0.01 picograms  TEV per  kilogram of body
 weight per day results in the incidence of one
 additional cancer case in one million people.
 According to  the Risk  Assessment Guidance  for
 Superfund Volume I, Human Health Evaluation Manual
 (Part A),  pages  7-15,  the toxicity  values  in the
                 32

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65.  Comment
          Integrated Risk Information System  (IRIS) database
          should be used in EPA risk assessments.  If
          information is not available in IRIS, then the
          toxicity values in the Health Effects Summary
          Tables (HEAST) may be used.  A toxicity value for
          2,3,7,8-TCDD is not available on IRIS as of August
          1995, but an oral and inhalation slope factor of
          1.5E+5 (150,000) mg/kg-day is presented in the
          HEAST database.  The toxicity value of 156,000
          mg/kg-day which was used in the Vertac risk
          assessment was based on the Rat toxicity study
          done by Kociba et al. in 1978.   The study by
          Kociba et al. was referenced in the HEAST and has
          been used historically to evaluate risk from
          exposure to dioxin and furans.   Current
          information from the EPA's dioxin reassessment
          also does not change the slope factor for dioxin.

          Hercules supports EPA's conclusion that dioxin-
          contaminated soils can be safely disposed of in an
          on-site hazardous waste landfill.   Hercules does
          not agree,  however,  that application of that
          remediation technology should be limited to soil
          containing less than 260 ppb dioxin.  None of the
          site soil is a principal threat,  especially when
          compared to the thousands of tons of concentrated
          wastes which have been,  or will be,  destroyed by
          incineration.   Based on both the technical
          effectiveness of landfilling dioxin-contaminated
          soil and the very low cost effectiveness of
          incinerating such soil,  Hercules believes that all
          excavated dioxin-contaminated surface soil should
          be placed into the on-site hazardous waste
          landfill that will be constructed as part of
          Operable Unit 1 remediation.  Landfilling will
          eliminate the need to transport the soil over
          public highways to an off -site incinerator,
          shorten the remediation time, and eliminate short
          term risks by not having to pre-process the soils
          (removal of coarse rock fraction) prior to
          shipment .
Raspons*: EPA agrees.
66.  Comment
          The Feasibility Study evaluated capping of
          contaminated soil in place and found the
          technology to be both technically and economically
          appropriate for areas of low contamination
          concentrations.  The very low potential for dioxin
          to migrate through  soil, as supported by  the low
          bioavailability, is supportive of covering
                           33

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          contaminated soil in place with a layer of clean
          soil.  Therefore, Hercules recommends that capping
          for some areas of low contaminant concentrations
          ... in the containment area with clean soil be
          selected as an optional remediation technology.
          Capping some areas of low contaminant
          concentration would have the additional benefit of
          minimizing the size of the landfill.  Hercules is
          aware that the Jacksonville community would like
          the landfill size to be minimized.

Response: EPA agrees.  When FPA re-evaluated the future
          landuse potential for the southern portion of the
          Vertac site,  i.e..  the southern 100 acres, EPA
          concluded that because of the existing on-site
          burial areas and landfills,  the construction of a
          new landfill as part of Operable Unit 1
          remediation,  and likelihood of long term on-site
          ground water monitoring and treatment,  these
          operations would substantially reduce commercial
          redevelopmer.1^  opportunities at this part of the
          site.

          Because the southern portion of the site will not
          be used for commercial/industrial development,
          other  remedial options presented in the OU2 FS and
          in the supplemental  proposed plan,  such as
          capping,  present a more cost effective  means of
          cleanup that  is fully protective of human health
          and the environment.   The cap for Operable Unit 2
          soils  would involve  covering the contaminated
          surface soil with a  6 inch layer of compacted
          soil,  and a 6  inch layer of  topsoil,  and re-
          vegetation.  Drainage controls would be
          implemented to prevent runon and runoff from
          capped areas.   The function of the cap  is
          principally twofold:   1)  To pre—ent direct
          exposure through dermal contact, inhalation, or
          ingestion by future  site workers maintaining the
          restricted access portion of the site,  and 2); to
          prevent potential off-site exposure to human and
          environmental receptors from the migration of
          contaminated soils  via various sediment transport
          mechanisms.

          Migration of dioxin-contaminated soils is
          adequately addressed by the 1 foot soil cap
          because:

          •    Dioxin has an extremely low solubility  in
               water and does not leach readily;
                           34

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                •    Site-specific studies have shown that dioxin
                    adheres strongly to fine grain particles and
                    soils with organic content of 3 percent or
                    greater, thereby further reducing its
                    leachability;

                •    The soil cap is not designed to protect
                    ground water at the site.  Ground water is
                    heavily contaminated with high concentrations
                    of dissolved phase contaminants and non-
                    aqueous-phase liquids (NAPLs), and as such a
                    technical impracticability (TI)  waiver will
                    be sought for this area of the site.  Ground
                    water remediation will most likely entail
                    hydraulic containment of the plume;

               •    The construction of an impervious
                    infiltration barrier over a major portion of
                    the site could substantially complicate
                    ground water flow and contaminant migration
                    prediction,  as well as affect the collection
                    of both dissolved phase contaminants and NAPL
                    recovery efforts in the existing French drain
                    system.   Several years have been invested in
                    developing a good conceptual ground  water
                    flow model for the site (which has been
                    confirmed through long term site testing and
                    monitoring),  and as such few benei^cs can be
                    found for installing an impermeable  cap,  and;

               •    An increase in the thickness of  the  soil cap
                    would not add additional protection  from
                    exposure for on-site work*- -~. They  will be
                    conducting maintenance activities under an
                    approved health and safety plan  that will
                    dictate the appropriate level of protection
                    should the need arise to breach  any  capped
                    areas.  Increasing the thickness of  the cap
                    also has certain negative aspects in that it
                    could increase the possibility of erosion in
                    areas graded from the cap surface to the
                    ground surface because the slope in these
                    areas would be greater.

67.  Comment:  The assessment of potential risk to human health
               from exposure to contaminated soil in the
               tetrachlorobenzene (TCB) spill area indicated that
               500 ppm of TCB in soil provided an acceptable risk
               if exposure of workers is limited.  The FS
               evaluated only two remedial technologies, thermal
               desorption and incineration, for  TCB-contaminated


                                35

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68,
69,
70.
           soil.   Although  evaluation  of  other  technologies
           was  focused on dioxin-contaminated soil,  Hercules
           believes  these evaluations  apply  to  TCB
           contaminated soil  as well.   Specifically, Hercules
           believes  soil which contains up to ten times the
           no-action level  of 500 ppm  TCB should be  placed
           into the  on-site landfill for  permanent
           containment.  Soil containing  more than 5,000 ppm
           TCB  and any crystalline TCB should be sent off-
           site for  treatment in a RCRA facility.  Although
           incineration is  the most likely treatment for
           these materials, ths ROD for these materials
           should  allow for other permitted treatments or
           recovery  options to be evaluated and selected
           during  the  remedial design  period.

Response:  EPA  currently cannot comment on the
           appropriateness  of the Hercules proposal to
           j.andfill  TCB-contaminated soils with
           concentrations between 500 ppm and 5,000 ppm
           because it was not an option considered by EPA in
           the  Feasibility  Study.   In addition,  EPA believes
           that this cleanup option could not have reasonably
           been anticipated by the public, and as such,  must
           be presented to the public for consideration or
           comment prior to further action by EPA.

                Pvil)lie Heating Comment•

Comment:   Why hasn't a comprehensive health study, morbidity
           study,  or a census on adverse health effects been
           conducted for the residents  in Jacksonville.

Response:  See  response to  Comment 38.

Comment:   The  Vertac  site  should be used as a dioxin
           research  facility where alternative treatment and
           disposal  technologies are developed and tested.

Response:  See  response to  Comment 42.

Comment:   EPA  needs to hold  a public  referendum on  all
           possible  alternatives for soils remediation,
           including chemical dechlorination.

Response:  Under the Superfund process each  citizen  has the
           opportunity to review and comment on cleanup
           alternatives proposed for each site.  This
           information is formally presented to the  public in
           the  Feasibility  study and Proposed Plan of Action,
           and  comments received are evaluated  by  EPA prior
                                36

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71.  Comment:
to drafting a Record of Decision for the site.
Chemical dechlorination was one of the
technologies evaluated in the Vertac Operable Unit
2 Feasibility Study and was presented as one of
the options in the May 1995 Proposed Plan for on-
site soils.  In addition, EPA discussed in length
many of the pros and cons associated with the use
of chemical dechlorination for dioxin-contaminated
soils at the public meeting held in Jacksonville
on June 15, 1995.  EPA received over 300 written
responses or signatures concerning the proposed
cleanup for soi.Tc at the Vertac site, and only
three comments concerned chemical dechlorination.
EPA believes that the public has had an
opportunity to provide EPA input on the use of
chemical dechlorination at Vertac.

EPA needs to develop a study to evaluate the
potential migration of contaminated ground water
off-site.
     Response: EPA has been eve.luating the condition of
               contaminated ground water at the Vertac site over
               the past several years and is currently in the
               process of developing a Proposed Plan that will
               present various cleanup alternatives and EPA's
               preferred alternative for ground water remediation
               at the Vertac site.  See also response to Comment
               44.

72.  Comment:  EPA needs to guarantee that there will be no
               further on-site incineration.

     Response: EPA cannot guarantee that if additional
               remediation efforts are needed at the site that
               they would not include on-site incineration.  EPA
               can, however, state that on-site incineration is
               not a part of any current remediation efforts
               slated for the site and that the on-site
               incinerator used in the remedy for OU 1 has been
               dismantled to the point that it would be cost-
               prohibitive to reassemble it and return it to
               operating condition.

73.  Comment:  There are concerns about fugitive emissions  in  the
               moving of the dirt,  including dust,  salt, and ash,
               and the salt soils,  and salt spills  around  the
               incinerator site.  Have they been sampled,  or  are
               they included  in the sampling process?
                                37

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 Response:  See response to Comment  41  on  dust  suppression.
           As a part of the cleanup operation  for  the
           northern portion of  the  Vertac site,  soil sampling
           will be  employed to  ensure  that dioxins and  furans
           are below the 1 ppb  action  levels set for this
           area of  the  site.
74.  Comment:
           EPA  should  consider using the local abandoned
           missile  silos as permanent waste storage
           facilities.
Response: This option was not considered by EPA in the FS,
          and EPA is very doubtful ^aat it poses a very
          realistic disposal alternative for dioxin-
          contaminated wastes.  EPA fails to see the
          advantages is disposing of dioxin wastes in
          missile silos over that of a hazardous waste
          containment unit that was designed to hold
          hazardous wastes.
75.  Comment:
          EPA should declare this a contaminated area,
          permanently restrict access, and buy out nearby
          homes and business properties.
Response: EPA disagrees.  EPA believes that approximately 50
          percent or 100 acres of the Vertac site can be
          returned to commercial/ industrial reuse after site
          cleanup efforts are complete.  Access to the
          remaining 100 acres of the site, i.e. , the old
          process plant area, will be restricted and
          engineering controls such as landfilling and
          capping will be employed to ensure that
          contaminants are controlled so that they will not
          pose an unacceptable risk to nearby residents,
          future site workers, or the environment.
          Residential areas that were found to have site
          contaminants above health-based levels were
          remediated as part of a removal action back in
          1987.
76.  Comment:
          Explain in terms of risk the difference between
          the 20 ppb dioxin cleanup standard that Hercules
          is proposing and EPA's 5 ppb dioxin cleanup level.
Response: First, the distinction between a cleanup standard
          and an exposure concentration must be made.  When
          soils are cleaned up to a certain concentration,
          say 5 ppb, the resulting concentration  of
          contaminants  in the soil after remediation will
          range from 4.9 ppb at their maximum  for some areas
          down to  zero  for others.  So, a 5 ppb cleanup
                           38

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77,
Comment:
 level will result  in an exposure concentration
 that will be the average of all the remediated
 area.

 Specifically for Vertac, if the site is cleaned to
 20 ppb for dioxin, then the resulting average
 dioxin concentration for the remediated areas will
 be 1.8 ppb.  The risk associated with being
 exposed to 1.8 ppb of dioxin under a commercial
 scenario ranges from 3X10"* based on RME estimates
 to 1X10"4 for Monte Carlo estimates.  These are
 both outside EPA's acceptable risk range.  A 5 ppb
 dioxin cleanup, however, will result in an average
 exposure concentration of approximately 0.67 ppb
 dioxin.  The risk associated with exposure at this
 concentration for a commercial scenario is 1x10^*
 for RME and 4X10-S for Monte Carlo.   Both are
within EPA's acceptable risk range.

Will the portion of the site that is cleaned up
and tested to be below 5 ppb have unrestricted
commercial access,  public access,  or public use?
78,
Response: Access to southern portion of the site (fenced
          area) will be restricted to site maintenance
          workers.  The Receiver for Vertac Corporation,
          which holds title to the property, has indicated
          to EPA a willingness to impose deed restrictions
          on the property that will prevent the property
          from being redeveloped.

          The northern portion of the site will be cleaned
          to a 1 ppb dioxin (TEQ) action "-vel and will have
          unrestricted commercial/industrial use.
          Generally, municipal zoning restrictions are used
          to control the type of development that occurs on
          a particular piece of property.  When EPA
          determines future site risks, guidance requires
          that EPA evaluate the past use of the property,
          and in most instances, future use of a piece of
          property follows its past or historical use.  EPA
          generally is prohibited from restoring a site to a
          future use that is above its historical use.  See
          response to Comment 31.

Comment:  Does EPA's risk assessment address potential
          exposure to children who may have access to this
          site  (the area that will have  commercial
          redevelopment) after the remediation is complete?
                                39

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 Response:  No.   The portions  of  the  site  that will be
           returned to productive  use  ( i . e . , the northern  100
           acres)  will have administrative  controls  such as
           deed restrictions  that  will prevent  future
           development other  than  commercial and light
           industrial.  However, as  a part  of EPA's  proposed
           remedy,  EPA will require  that  the northern portion
           of the  site be cleaned  to a 1  ppb dioxin  TEQ
           action  level.  This action level has been used  by
           EPA  as  the  cleanup standard for residential
           properties  adjacent to  the Vertac property and
           floodplain  soils along  residential stretches of
           Rocky Branch Creek, and as such, any incidental
           exposure  from children  accompanying a parent to
           work would  not pose an  unacceptable risk  to the
           child.
79.  Comment:
          Clean the area of the site that will be used for
          commercial/ industrial reuse to 1 ppb (dioxin) and
          the fenced portion of the site to 5 ppb (dioxin) .
Response: See response to Comment 14.
80.  Comment:
          We encourage the restoration of the site to its
          original condition prior to development by
          Hercules and its predecessors.  This includes,
          removal of all structures, removal of all buried
          waste, removal of all contaminated soila, and
          restoration of ground water to background
          standards.  Partial restoration of the site is not
          in the best interest of the community or its
          future residents.  The future use of the site
          should be able to support any activity, including
          parks, residences, cojtmercial establishments, or
          industrial facilities.
Response: See response to Comment 31.
81.  Comment
82.
          The average person in Jacksonville would like to
          see the site cleaned up to conditions that existed
          prior to Hercules' operation, including the
          excavation and off-site disposal of the existing
          on-site landfills.
Response: See response to Comment 31.

Comment:  It appears that some of the buildings  at the site
          may remain.  All the buildings  should  be removed.

Response: See response to Comment 12.
                           40

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 83.   Comment:   The  EPA  pole  barn  buildings at the northern
                portion  of  the  site  should be cleaned and  left in
                place.   These building could be used by the city
                as a new recycling center.

      Response:  The  disposition of the existing pole barns on the
                site are not  part  of the proposed remedy for OU2.
                However,  EPA  is willing to clean and leave these
                structures  in p]-*~e  if they are considered to be
                valuable.   Agreement from the City and the Vertac
                Receiver will be sought should the City and the
                Receiver have such an interest.

 84.   Comment:   Highly contaminated soils should be treated or
                taken off-site  rather than placing all that soil
                into an  on-site landfill.

     Response:  EPA has  determined that off-site disposal of the
               highly contaminated soils is not cost-effective
               and affords only minimal additional protection
               over secure containment on-site in a RCRA Subtitle
               C landfill.

85.  Commen^:  The salt and ash residuals from the completed
               incineration operation should not go into the on-
               site landfill.

     Response: EPA is presenting information to the public in an
               Engineering Evaluation/Cost Analysis which will
               explain options being considered by the Agency for
               the disposal of approximately 40,000 drums of salt
               and ash generated during the on-site incineration
               of drummed herbicide wastes and approximately
               1,000 tons of pallets used in the storage of these
               wastes.  EPAs preferred alternative for salt, ash
               and pallets is containment in an on-site RCRA
              •Subtitle C  landfill.  Citizens will have 30 days
               to comment  on EPA's proposal when it is released.

86.  Comment:  The restricted  access portion of the site should
               be much  smaller than that proposed.  Minimize the
               portion  of  the  site that will remain fenced.

     Response:  See  response  to Comment 11.

 87.   Comment:   We had origionally hoped that while the
                incinerator was operating out at the site  that all
                the  contaminated soil would have been processed,
                which would have allowed for a smaller landfill.
                If there are  other technologies that could be used
                                41

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           at the site to remediate the soils and reduce the
           size of the landfill,  they should be considered.

 Response:  Other technologies were evaluated in the
           Feasibility Study for  treating on-site soils,  but
           were not adopted  by EPA as the preferred
           alternatives for  OU 2.
88.  Comment
           The  citizens  of Jacksonville,  the business
           community, the civic clubs, and the city officials
           all  are  saying the same thing, and that is, clean
           it,  restore it, and give us back an area at least
           equivalent to what we started  out with.  If some
           waste must be left out there,  make it as little as
           possible.
Response: See response to Comment 31.
89.  Comment
          EPA has stated that the total amount of dioxins
          and furans at the site are approximately 20
          percent high-- as toxicity equivalents than for
          2,3,7,8-TCDD alone.  The dioxin reassessment
          indicates that the ratio should be approximately
          10 times greater than for 2,3,7,8-TCDD alone.  How
          does EPA derive the 20 percent figure?

Response: The 20 percent number used by EPA was based on
          site-specific sampling conducted at Vertac.  In
          1994, five areas at the Vertac site were resampled
          using EPA Method 8280 to determine the dioxin and
          furan congener concentrations for those areas.
          The analytical results from each area was used to
          calculate a Toxic Equivalency (TEQ) concentration
          for the sample collected, and the ratio of
          2,3,7,8-TCDD to TEQ was determined.  The ratio of
          2,3,7,8-TCDD to TZQ ranged between 0.73 and 1.00.
          This suggests that other dioxin and furan
          congeners are present at the site that would
          contribute to the overall dioxin toxicity
          calculated for site.  As a result of the dioxin
          resampling effort, EPA is requiring that all soil
          grids at Vertac site be remediated for dioxin and
          furans expressed as 2,3,7,8-TCDD toxicity
          equivalents.
90.  Comment:
          Has EPA evaluated the various isomers of
          tetrachlorobenzene  (TCB) from the spill area to
          determine the appropriate cleanup level, or has  it
          just considered a common potency for all.  Some  of
          the isomers are dioxin-like and this should be
          factored into the cleanup determination.
                           42

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     Response:  EPA  evaluated  the  toxicity  of tetrachlorobenzene
                and  some  of  its  isomers  from the data available in
                EPA's  Integrated Risk  Information System  (IRIS)
                database.  The studies used to develop the
                reference dose (RfD) for tetrachlorobenzene
                included  the evaluation  of  1,2,4,5-
                tetrachlorobenzene, 1,2,3,4-tetrachlorobenzene,
                and  1,2,3,5-tetrachlorobenzene isomers.

91.  Comment:   Has  EPA evaluated  other  dioxin-like compounds at
                the  site  such  as chlorinated biphenalenes?  These
                compounds are  as toxic as dioxins and are expected
                to be present  and  could  radically change the risk
                assessment.

     Response:  During the remedial investigation of the site
                Hercules, Incorporated evaluated compounds in site
                soils based on raw materials used at the site,
               manufacturing  intermediates, and finished
               products.  These compounds included compounds such
               as toluene, chlorinated herbicides,  chlorinated
               phenols and dioxin.  Because the history of site
               operations was known,  extensive screening for
               numerous other compounds was not conducted.

92.  Comment:  EPA should considered using other treatment
               technologies such as chemical dechlorination,  base
               catalyzed decomposition,  or bio-remediation to
               destroy the approximately 2,000 tons of soils
               slated for off-site incineration.   Even if these
               technologies do not get the dioxin contamination
               down to the cleanup standard,  it would have
               reduced the dioxin level to a c'-^ree that it could
               be dealt with in other ways.

     Response: Both chemical dechlorination and biological
               treatment were evaluated in the Vertac Operable
               Unit 2 FS.  Biological treatment using "white rot
                fungus" was found to be  in the developmental
                stage, and limited bench scale tests have been run
                on contaminated media  containing 2,3,7,8-TCDD.
                Currently no venders offer this remediation
                service commercially.

                Chemical  dechlorination  along with base catalyzed
                decomposition  (BCD) were also evaluated and found
                to be successful in treating dioxin-contaminated
                media.  Most tests conducted to date have been
                either bench scale tests or field trial tests and
                considerable additional  testing would most  likely
                be necessary to  confirm  the efficiency of this
                                43

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93,
comment:
94,
Response:

Comment:
95.
 technology  for Vertac  soils.  One  of  the major
 concerns  that has  been raised during  on-site
 incineration was the health effects associated
 with  emissions from the  incinerator.  The Region
 also  considered those  concerns when it evaluated
 whether to  pursue  chemical dechlorination or BCD
 for soil  remediation at Vertac.  Information
 available from a test  conducted at the Koppers
 Superfund site showed  that dioxin and furan
 emissions had to be addressed with additional
 engineering controls before the full scale
 operation could proceed.  Therefore, EPA did not
 prefer this option for the small amount of soil
 that would  have required treatment at Vertac.

 The dioxin  data collected for the Vertac site
 soils was for 2,3,7,8-TCDD only and not toxicity
 equivalents.  Why were equivalents used in the
 risk assessment?

 See response to Comment 43.

 In the risk assessment a gastrointestinal
absorption of 0.55 was assumed for TCDD
equivalents ard was derived from the U.S.  EPA's
 1989 Human Health risk guidance.   Is that document
still valid after the dioxin reassessment.
Response: Yes.

Comment:  What criteria did EPA use to define the 260 ppb
          cutoff for dioxin soil treatment and landfilling,
          i.e., your determination between high
          concentrations and lew concentrations.   It looks
          as though it could have been entirely economic.

Response: The 260 ppb treatment level for dioxin-
          contaminated surface soils was based primarily on
          a cost/benefit balance.  The balance that EPA
          weighed was the high cost associated with off-site
          incineration and the reduction of toxicity or
          mobility of soil contaminants through treatment.
          EPA looked at the reduction in the total amount  of
          dioxin that would be achieved by incrementally
          incinerating the most highly contaminated grid at
          the site down to the least contaminated, and the
          resulting cost for that  incineration.  What was
          found was that by incinerating the 8 most highly
          contaminated grids at the site approximately 70
          percent of all the dioxin in site soils was
          destroyed.  However, by  incinerating the ninth
                                44

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9 6.  Comment:
     Response;
97,
98,
Comment:



Response:


Comment:
     Response:
99,
Comment:
     Response:
 grid,  only an additional  0.5  percent was  destroyed
 at a cost of  an additional  $1 million.  After
 treatment of  the 8th  grid,  it became apparent  that
 treatment of  additional grids yielded little
 additional benefit.

 Who developed Monte Carlo Modelling? My
 indication is that industry actually developed
 Monte  Carlo in cr^er  to raise the cleanup levels
 at various sites.

 Monte  Carlo probabilistic modelling  is a
 statistical application that  nas been used in  a
 wide variety  of  fields to evaluate population-type
 data.  This modelling technique is widely used by
 researchers in universities,  industry, and the
 government.   This modelling technique is  unique in
 that it looks at data as  a distribution for a
 given  input parameter, rather than as a fixed
 point.  Application of Monte  Carlo modelling does
 not result  in laxer cleanup standards for a given
 contaminant.

 Is the landfill that  is to be constructed under
 the ROD for Operable Unit 1 going to be built  to
RCRA hazardous waste  specifications?

Yes.  The on-site landfill will be constructed to
RCRA Subtitle-C standards.

 EPA should consider reducing the toxicity of the
 soil through treatment prior to putting it into
the on-site landfill,  even if requires that
 several different alternatives be used.

 From a cost/benefit perspective, there is very
 little benefit from pretreating dioxin-
 contaminated  soils to reduce toxicity prior to
 disposal  into a secure RCRA Subtitle C landfill.
 The Subtitle  C landfill will be designed  and
 maintained  to strict  standards, and  therefore
 exposure  to waste materials placed in the landfill
 would  be  considered a very remote possibility.

 Is EPA considering capping  any of the dioxin-
 contaminated  soil at  the  site as Hercules is
 proposing?

 Yes.   In  the  proposed plan, EPA had  origionally
 envisioned that approximately 50 percent  of the
 southern  100  acres of the site would eventually be
                                45

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returned to commercial/industrial use.  However,
after reevaluating the long term operational and
maintenance requirements for this area of the site
(i.e., maintaining the caps on the existing site
burial areas and the RCRA Subtitle C landfill, and
operation and maintenance of the ground water
treatment system), EPA believes that these
operations will substantially reduce the chance
for extensive future redevelopment opportunities
on the southern 100 acres.  Because access to this
area of the site will remain restricted (except
for site maintenance workers), other remedial
options presented in the OU 2 FS and set out in
the OU 2 Proposed Plan, such as capping, present a
more cost effective means of cleanup that is fully
protective of human health and the environment.
                 46

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                      ATTACHMENT B


                      SUPPLEMENTAL

               RESPONSIVENESS SUMMARY

     The Environmental Protection Agency (EPA) has prepared this
 Supplemental Responsiveness Summary in  response to comments
 received at the open house held in Jacksonville, Arkansas, on
 March 5, 1996, and during the public comment period that ran from
 .larch 6, 1996, to April 29,  1996,  regarding the Supplemental
 Proposed Plan of Action for Operable Unit #2 (OU2) media at the
 Vertac Superfund Site.

     This Responsiveness Summary addresses comments received upon
 the Supplemental Proposed Plan for OU2,  and does not address
 those comments EPA received on the original Proposed Plan for OU2
 dated May 23,  1995.   EPA provided the public with its response to
 those comments on March 5,  1996,  and those responses are attached
 to this ROD as Attachment A.

     Written comments on the May 1995 Supplemental Proposed Plan
were submitted by the Arkansas Department of Pollution Control
 and Ecology (ADPC&E),  Hercules,  Incorporated (Hercules),  State
 Senator Bill Gwatney,  the Concerned Citizens Coalition, the
 Environmental Compliance Coalition,  the  Jacksonville Chamber of
Commerce,  the Jacksonville Commerce Corporation, City of
Jacksonville Office  of Economic Development, the Jacksonville
 Serotoma Club,  the Jacksonville Lions Club, the Arkansas Peace
Center,  Vietnam Veterans of  America,  the Environmental Health
Association of Arkansas,  Jacksonville Mothers *nd Children's
Defense Fund,  and numerous concerned citizens.

     As was explained in detail within the Supplemental Proposed
Plan issued on February 26,  1996,  EPA Administrator Carol M.
Browner issued a series of administrative reforms tor the
 Superfund Program on October 3,  1995.  One purpose of those
 reforms was to control remedy costs and  to promote cost
 effectiveness,  and the reforms directed  EPA to base site cleanup
 decisions on reasonably anticipated future land usage and
 reasonable contaminant exposure scenarios based on the future
 land usage.

     As a result of those reform measures, and due to the ongoing
 deadlock over the Federal budget occurring at the time, Region  6
 revised the proposed plan of action for OU2 and developed the
 Supplemental Proposed Plan issued on February 26, 1996.  That
 supplemental plan eliminated the off-site incineration component
 of the original proposed plan, included capping of  soils having
 dioxin concentrations between 5-50 parts  per  billion (ppb),  and
 proposed on-site landfilling of soil contaminated with dioxin
 concentrations in excess of 50 ppb.

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     The  following are the comments received by EPA Region  6
during the  45-day comment period between March 6,  1996, and April
29,  1996, and the responses from the EPA are included below each
comment.

1)   Comment:  The commenter is opposed to constructing the on-
     site landfill on the west side of the Rocky Branch CTO^IC and
     stated that it would be more desirable to site the landfill
     within the French drain system since the land on the west
     side is considered "clean."  Also, this commenter expressed
     some concern with respect to the continued integrity of the
     ground water monitoring wells.

     Response:  The siting of the landfill is considered
     appropriate since it is on-site and within the general area
     of contamination at the Vertac site.   Based on numerous
     comments during meetings with the community,  the most
     desirable location was west of Rocky Branch Creek where the
     new landfill could be "out of site - out of mind."  See
     response to comment #34 in the Original Responsiveness
     Summary in Attachment A.

     The Hercules,  Inc.,  a potentially responsible party (PRP),
     will be conducting continuous groundwater monitoring at the
     site.  More information on ground water will  be included in
     the ROD for the Groundwater operable Unit (OU3),  wnich EPA
     plans to issue concurrently with the ROD for  OU2.

2)   Comment:   The commenter (Hercules,  Inc.)  provided two
     letters stating that the trichlorobenze (TCB)  and TCB-
     contaminated soil having TCB concentrations between 500 ppm
     and 5,000 ppm should be landfilled on-site, bu_ agreed with
     EPA that the TCB above 5,000 ppm should be incinerated off-
     site.

     Response:  The on-site landfilling of TCB-contaminated soils
     above 500 ppm was not an option considered by EPA in the
     Feasibility Study, and therefore was not presented to the
     public for comment.   In addition, in the ROD for OU2, EPA
     has chosen to consolidate within the on-site RCRA Subtitle C
     hazardous waste landfill low level threat material having
     the similar characteristic of dioxin contamination.
     However,  the TCB-contaminated soils with concentrations
     between 500 and 5,000 ppm TCB do not share that common
     characteristic.  In addition, because Hercules' proposal has
     not been held out for public comment, EPA cannot include
     that proposal within its remedy decision for  OU2.

3)   Comment:  The commenter stated that the existing fenced
     areas  at the site were unacceptable since the fence  along
     the south side of the site is considered a detriment to

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     property values  in the area.  The commenter further stated
     that the site should be completely remediated so that the
     site could be "useful" in the future.

     R«sponsa:  One of the EPA's goals with respect to the remedy
     selected for OU2 is to allow the greatest amount of the site
     to be unrestricted by such structures as fencing to permit
     the commercial redevelopment of the greatest amount of the
     site.  However, EPA will not know the extent of the fencing
     that will be necessary for areas around the eastern and
     southern portions of the site until the remedial
     design/remedial action phase of the OU2 remediation.
     Nonetheless,  the northern and western fenced areas are
     around the existing landfills, and the French Drain must
     remain in place due to the fact that those areas were
     delineated by a 1984 order of the U.S. District Court for
     the Eastern District of Arkansas.  In addition,  it will be
     necessary to maintain some fencing around areas where ground
     water extraction and monitoring wells currently are located
     or will be placed upon the execution of the ground water
     operable unit ROD (OU3)  to protect those wells and to
     prevent trespassers from interfering with them.   Finally,
     fencing will also have to be maintained around the existing
     wastewater treatment plant since that facility will continue
     to be operated during the extended periods of operation and
     maintenance (O & M)  for various of the site's operable
     units .

     With respect to the comment regarding a complete remediation
     of the site,  EPA believes that the remedy selected in this
     ROD for OU2 allows the greatest amount of the site's future
     useful reuse in a manner that is consistent with the new
     direction of the Superfund program and that meets the
     public's general approval.

4)   Comment:  The commenter provided voluminous petitions from
     local citizens, and numerous other letters from individuals,
     endorsing and reiterating the preference for the
     Jacksonville Plan.
               While EPA acknowledges tne merits of the
     Jacksonville Plan, it is not cost effective when evaluated
     along with the other eight criteria set out in the Superfund
     statute for evaluating Superfund remedies.  The remedy
     selected in the ROD for OU2 results in a cost effective
     remedy that is protective of the human health and the
     environment, recognizes the reasonably anticipated future
     land use for the  site, which allows for a substantial amount
     of the site to be redeveloped for commercial /industrial
     uses, is supported by the State of Arkansas, and is

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     consistent with the Agency's strategy for dealing with low
     level threat wastes.

5)   Comment:  The commenter expressed concern about reduced
     property values of real estate in areas adjacent to the site
     to the west and requested that all material that might
     constitute a hazardous waste be removed from the site
     immediately.  The commenter also requested that a public
     statement be made when any and all of the hazardous wastes
     have been removed from tho site so that it would be suitable
     for industrial use.  Finally,  the commenter stated that if
     the requests could not be performed then adjacent landowners
     should be compensated for the  true loss of value to the
     property.

     Response:  As discussed earlier in this Responsiveness
     Summary, a 1984 Court Order resulted in the permanent
     location of several unlined landfills and the French drain
     system on-site.   In addition,  as discussed in the OU2 ROD,
     EPA considers the material to  be consolidated within the on-
     site RCRA Subtitle C hazardous waste landfill to constitute
     low level threat media.   The Agency has stated in the
     National Contingency Plan (NCP),  40 CFR Part 300,  that the
     preferred method of addressing such low level threat media
     is containment,  and that the use of the technologies
     employed in constructing,  operating,  and maintaining such a
     hazardous  waste landfill have  been proven.   Therefore,  the
     on-site containment of low level threat media within the on-
     site RCRA Subtitle C landfill  is appropriate in light of the
     above comments and when considering that the 1984 Court-
     ordered remedy resulted in the on-site burial of principal
     threat materials in unlinod landfills that do not meet the
     technological standards of the RCRA Subtitle C unit
     currently being constructed.

     Nonetheless,  the remedy selected in this ROD will result in
     a substantial amount of the site being available for
     commercial/industrial redevelopment.  Upon completion of the
     OU2 remedy, the public will be made aware of the fact that
     those portions will be available for such redevelopment.

     Finally, the conditions at the site are not due to the
     actions of the Federal government, and therefore, any loss
     of property value is not compensable by the United States or
     any of its agencies.

6)   Comment:  The commenter offered financial management
     services and stated that a  local bank could provide direct
     deposit and electronic transfer capabilities.  Also, the
     commenter further stated that the EPA was spending more
     money on the cleanup than necessary.

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     Response:  There is no known need for electronic transfer
     capabilities to fund this project. In addition, EPA believes
     that the remedy selected for OU2 is cost effective and fully
     protective of the human health and the environment.
     Therefore, EPA disagrees that it is spending more money at
     the site than is necessary.  Furthermore, it is the intent
     of EPA to order Hercules, Inc.,  to perform the OU2 remedy.

7)   Comment:  The commenters stated that there has been economic
     damage to the City of Jacksonville because of the publicity
     surrounding the Vertac site.  Before Vertac, Jacksonville
     was one of the fastest growing communities in the area,  and
     as a result of the Vertac situation,  adjacent communities
     such as Cabot and Sherwood have  experienced economic and
     population booms.   The City of Jacksonville Chamber of
     Commerce has formed an organization to purchase industrial
     property to enhance recruitment  opportunities for potential
     industry and associated jobs.  The Commenter has urged the
     EPA to clean the northern portion of  the site to 1 ppb and
     is eager for the EPA to donate this property to the City of
     Jacksonville so that this land can be included in industrial
     marketing efforts.   The commenter further requested that
     careful consideration should be  given to the strip of
     property along Marshall Road for long term future
     development as it  relates to cleanup  levels.

     Response:   The EPA recognizes that the City of Jacksonville
     has suffered a continued economic loss as a result of the
     Vertac site.   However,  the cleanup standards included in
     this ROD will allow future use of the northern portion of
     the site and will  result in an average d^ ~vin concentration
     of 1 ppb or less.   Property along Marshall Road will be
     cleaned to a dioxin concentration of  5 ppb thereby providing
     for future redevelopment.  Due to the long term operation
     and maintenance (O & M)  activities necessary with respect to
     the wastewater treatment plant,  ground water extraction and
     monitoring wells,  and the existing landfills within the
     southern portion of the site,   future land use exists for
     only a portion of the southern property.  The risk
     assessments performed for OU2 have established that soil
     concentrations of up to 5 ppb dioxin are fully protective
     for future commercial/industrial land use.

     Finally, while the Vertac site belongs to the Vertac
     Receiver, and is not the property of the EPA, EPA has and
     will continue to encourage the future redevelopment of all
     available remediated portions of the site.

8)   Comment:  The commenter  (the Department of  the  Interior  (
     DOI)) has stated that based on numerous previous  studies,
     unacceptable levels of TCDD  (dioxin)  in sediments  already

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     exist  in Rocky Branch Creek and Bayou Meto; and that if the
     source of contamination is not controlled, even more dioxins
     will be loaded into this system which would pose an
     unacceptable risk to fish, mammals and birds.  Further, the
     commenter indicated that the proposed capping of the
     southern portion of the site does not provide a permanent
     remedy since dioxin contamination can be uncovered during
     flood  events, resulting in continued loading of dioxin into
     the system.

     Response:  There is no doubt that dioxin has been released
     to Rocky Branch Creek and subsequently into Bayou Meto.
     However, the remedy selected in this ROD does not include a
     capping component, as was recommended in the Supplemental
     Proposed Plan for OU2.   Instead,  the remedy selected in this
     ROD will result in the excavation and consolidation within a
     RCRA Subtitle C hazardous waste landfill of dioxin
     contaminated soils at concentrations of 5 ppm and above for
     the entire site.   EPA data indicate that the average post-
     remediation soil levels will be at or below 1 ppb.   The
     excavation and on-site consolidation of soils with dioxin
     concentrations of 5 ppb and above will provide for
     commercial/industrial remedial actions.   Therefore,  the
     implementation of the remedy selected in this ROD will
     eliminate dioxin concentrations in site soils,  excepting the
     areas subject to the 1984 Court Order,  in excess of 5 ppb,
     which will effectively eliminate those soils as a source of
     off-site contamination.   Finally,  because storm water run-
     on/run-off measures will be implemented in connection with
     the remedy selected in this ROD,  site soils or surface run-
     off waters will be prevented from leaving the site,  and most
     storm waters will be captured and treated in t  -. on-site
     wastewater treatment facility.

9)   Comment:  This comment was provided by the City of
     Jacksonville by Resolution #47 (#2-96)  which opposed the
     modification of the original proposed plan issued May 1995,
     and reiterated support of the Jacksonville Plan.

     Response: With the exception of the off-site incineration of
     up to  eight highly-contaminated grids, the remedy selected
     in this ROD is substantially similar to the remedy proposed
     in EPA's original May 1995 Proposed Plan for OU2.  As
     discussed above, the Jacksonville Plan, while having some
     merit, is not a cost effective remedy that takes fully into
     account the reasonably anticipated future land use for the
     site or acknowledges that the OU2 media constitute low level
     threat media, as opposed to principal threat media.

10)  Comment:  This comment  is a summary of numerous  letters  and
     petitions from various members of the Jacksonville community

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expressing concern with EPA's proposal to "reduce the scope"
of the cleanup of the Vertac site.  Also, included in the
letters and petitions is a statement supporting the
"Jacksonville Plan."

Response: As discussed in the response to Comments 5 and 10,
EPA believes that the remedy selected in this ROD is fully
protective of the human health and the environment, is cost
effective, and meets with general public approval.

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ATTACHMENT C

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                          STATE OF ARKANSAS
         DEPARTMENT OF POLLUTION CONTROL AND ECOLOGY
                     8001 NATIONAL DRIVE, P.O. BOX 8913
                     LITTLE ROCK, ARKANSAS 72219-8913
                           PHONE: (501) 682-0831
                            FAX: (501) 682-0880
 September 16,  1996
Jane  Saginaw
Regional  Administrator
U.S.  Environmental  Protection Agency
1445  Ross Avenue
Suite 1200
Dallas, Texas  ^5202
Dear Ms. Saginaw:


This  letter is  to  inform you  that the  Arkansas  Department of
Pollution Control  and Ecology  (ADPC&E)  formally concurs with the
Operable Unit 2 Record  of  Decision (ROD)  and the amended 1990 Off
Site ROD for the Vertac Superfuni Site.

ADPCScE also concurs with the ROD  for Operable Unit 3 provided  that
any changes  to  the ground water  plume  containment trigger levels
will be more stringent  than those which are currently contained in
the ROD.   In addition, ADPC&E must  be involved  in the decision
making  process  should changes   to  the  trigger   levels  become
necessary.

I commend your  staff in their efforts in achieving  this  goal.

Sincerely,
Randall  Mathis
Director

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