United States        Office of
          Environmental Protection   Emergency and
          Agency           Remedial Response
EPA/ROD/R04-93/133
December 1992
&EPA    Superfund
          Record of Decision:
          Redwing Carriers/Saraland,
          AL

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50272-101	
  REPORT DOCUMENTATION
           PAGE
1. REPORT NO.
EPA/ROD/R04-93/133
3. Recipient's Accession No.
   Title and Subtitle
   SUPERFUND RECORD OF DECISION
   Redwing Carriers/Saraland, AL
   First Remedial  Action - Final
                                          5.  Report Date
                                                   12/15/92
7.  Author(s)
                                                                     8.   Performing Organization Rept. No.
9.   Performing Organization Name and Address
                                          10  Project Taskwork Unit No.
                                                                    11.  Contraet(C) or Grant(G) No.
                                                                    (C)

                                                                    (0)
12. Sponsoring Organization Name and Address
   U.S.  Environmental  Protection  Agency
   401 M Street,  S.W.
   Washington, D.C.  20460
                                          13.  Type of Report & Period Covered

                                             800/800
                                                                    14.
15. Supplementary Notes
                       PB94-964030
16. Abstract (Limit: 200 words)

  The 5.1-acre Redwing Carriers/Saraland site is a former trucking terminal and current
  apartment  complex located in Saraland,  Mobile County,  Alabama.  Land use in the area  is
  predominantly residential,  with wetlands  and woodlands situated near the site, and
  three  layers of hydrogeologic units,  including an alluvial and surficial aquifer,
  beneath the  site.  The estimated 160  people who reside onsite in the Saraland Apartment
  complex use  wells located to the north of the site to  obtain their  drinking water
  supply, and  although not  currently utilized,  the alluvial and surficial aquifers are  a
  potential  source of drinking water.   There are one grass-covered and two concrete-lined
  drainage ditches onsite that eventually empty into the Norton Creek.  From 1961 to
  1971,  Redwing Carriers operated a trucking company that transported substances such as
  asphalt, diesel fuel, chemicals, an'd  pesticides from local plants and that used the
  site as a  terminal for cleanup,  repairing, and parking the fleet of trucks.  Sometimes
  during the cleanup process,  untreated substances were  released sometimes directly  into
  the ground.   Many of the  contaminants likely were diluted and washed away during storm
  events; however, many of  them adhered to  the asphalt,  which was deposited later across
  the property during maintenance operations.  In 1971,  Redwing Carriers sold the
  property,  which was converted into an apartment complex.   In 1984,  the State

  (See Attached Page)
17. Document Analysis    a. Descriptors
   Record of Decision  - Redwing Carriers/Saraland,  AL
   First  Remedial Action - Final
   Contaminated Media:  soil, sediment,  debris,  sludge, gw
   Key  Contaminants: VOCs (benzene),  metals  (chromium)

   b.  Identifiers/Open-Ended Terms
   c.  COSATI Field/Group
18. Availability Statement
                         19.  Security Class (This Report)
                                   None
                                                    20.  Security Class (This Page)
                                                              None .
         21.  No. of Pages
                 102
                                                                              22. Price
(See ANSI-Z39.18)
                                   See Instructions on Rtvtrse
                                                   OPTIONAL FORM 272 (4-77)
                                                   (Formerly NTJS-35)
                                                   Department of Commerce

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EPA/ROD/R04-93/133
Redwing Carriers/Saraland, AL
First Remedial Action - Final

Abstract (Continued)

investigated complaints about a tar-like sludge oozing to the surface at numerous
locations.  In 1985, EPA studies detected high concentrations of 1,2,4—trichlorobenzene
and naphthalene in the soil and in leachate coming from the sludge, which has been related
to onsite ground water contamination. Subsequently, EPA required Redwing to remove any
visible sludge detected on the surface of the site. This ROD addresses the first and final
remedial action for the contaminated source material and ground.water affecting the
surficial and alluvial aquifers as a drinking water source.  The primary contaminants of
concern affecting the soil, sediment, debris, sludge, and ground water are VOCs, including
benzene; and metals, including chromium.

The selected remedial action for this site includes temporarily relocating onsite
residents during excavation; removing buildings or onsite structures as needed to
facilitate excavation; excavating contaminated soil, sediment, and sludge until the
remaining source material achieves excavation levels; staging and temporarily storing the
excavated material onsite; treating the surface soil, sediment, and sludge offsite using
thermal treatment, if necessary; dewatering and solidifying the subsurface soil offsite,
if necessary, before disposing of the residuals in an offsite landfill; analyzing,
treating, and discharging the water from the dewatering process in an appropriate manner;
removing, sorting, and treating offsite, if necessary, all contaminated debris, including
sidewalk slabs and pavement areas; backfilling excavated areas with clean material;
extracting approximately 12,000,000 gallons of contaminated ground water from the
surficial aquifer using extraction wells and french drains and treating it onsite using
biological treatment and sand/activated carbon filtration, with a supplemental treatment
step, if necessary, to remove contaminants not affected by biotreatment; discharging the
treated ground water offsite to a POTW or onsite in nearby surface water; disposing of
residual sludge and spent carbon offsite in an approved facility; allowing for natural
attenuation of the alluvial ground water; and monitoring the surface soil, sludge seeps,
and ground water in the alluvial aquifer to monitor the riatural attenuation process.  The
estimated present worth cost for this remedial action is $7,002,562, which includes an
estimated present worth O&M cost of $518,000.

PERFORMANCE STANDARDS OR GOALS:

Soil, sediment, and sludge cleanup goals and excavation levels are based on a human health
risk from inhalation or ingestion and ground water protection with a cleanup level of 15
ug/1 for lead. Chemical-specific goals include acetone 36 ug/kg; aldrin 4 ug/kg; alpha-BHC
0.5 ug/kg; benzo(a)anthracene 1,025 ug/kg; benzo(a)pyrene 94.9 ug/kg; benzo(b)fluoranthene
540 ug/kg; carbon tetrachloride 9,590 ug/kg; chloroform 70 ug/kg; chromium 47,000 ug/kg;
chrysene 362 ug/kg; 4,4-DDT 566 ug/kg; dieldrin 0.1 ug/kg; gamma-BHC 3.2 ug/kg; methylene
chloride 0.6 ug/kg; nickel 30,000 ug/kg; vanadium 156,000 ug/kg; and vernolate 55 ug/kg.
Ground water cleanup goals are based on SDWA MCLs.  Chemical-specific ground water cleanup
goals include acetone 1,120 ug/1; aldrin 0.00317 ug/1; alpha-BHC 0.00855 ug/1; beryllium 4
ug/1; bis(2-ethylhexyl)phthalate 6 ug/1; carbon disulfide 47.6 ug/1; chloroform 100 ug/1;
chromium 50 ug/1; 4,4-DDT 0.158 ug/1; dieldrin 0.00337 ug/1; gamma-BHC 0.2 ug/1; methylene
chloride 5 ug/1; nickel 100 ug/1; vanadium 78.1 ug/1; and vernolate 11.2 ug/1.

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        RECORD OF DECISION
REDWING CARRIERS,  INC.  (SARALAND)
             NPL SITE

        DECEMBER  15,  1992

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THE DECLARATION

Site Name and Location

The  Redwing Carriers,  Inc.  (Saraland)   Site  (Redwing  Site)  is
located in Mobile County,  Alabama  in the corporate limits of the
City of Saraland. The 5.1 acre site is about  eleven miles north of
Mobile, Alabama.  The Redwing Site is bounded to the east by U.S.
Highway 43 and  a skating rink.   On  the  south  it  is  bounded by a
United Gas Pipe Line easement.  A residential development is south
of the  pipe  line easement.   The Redwing Site is  bounded on the
north by a trailer park, and on the west  by  an undeveloped lot.

Statement of Basis and Purpose

This decision document  presents the selected remedial action for
the Redwing  Site in Saraland,  Mobile  County,  Alabama,  which was
chosen in accordance with the  Comprehensive Environmental Response
Compensation  and  Liability  Act  (CERCLA),. as  amended  by  the
Superfund Amendments and  Reauthorization Act (SARA),  and,  to the
extent  practicable,  the  National   Oil  and  Hazardous  Substances
Polluticn Contingency Plan (NCP).   This  decision is  based on the
administrative record for  this  site.

The State of Alabama concurs with the selected remedy.

Assessment of the Site

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

Description of the Selected Remedy

The Major components of the remedy are:

•    Excavation of sludge, sediments, and contaminated soils.

     Off-site treatment/disposal of  contaminated soils, sediments
     and sludge.

     Regrading and backfill of  excavations using clean, compacted
     fill material.

•    Temporary and possibly permanent relocation  of residents with
     the potential demolition of selected apartment units.

     On-site treatment of contaminated groundwater in  the surficial
     aquifer.  Monitoring and possible withdrawal and treatment of
     groundwater in the  alluvial aquifer.  Treated groundwater will
     be discharged to a Publicly Owned Treatment Works (POTW), or
     if unavailable, to a  nearby surface  water body.

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SUMMARY OF REMEDIAL ALTERNATIVE SELECTION

    REDWING CARRIERS,  INC.  (SARALAND)
            SARALAND,  ALABAMA
               Prepared By

  U.S.  ENVIRONMENTAL PROTECTION AGENCY
                REGION IV
             ATLANTA, GEORGIA

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 THE DECLARATION

 Site Name and Location

 The  Redwing  Carriers,  Inc.   (Saraland)  Site  (Redwing  Site)  is
 located in Mobile County, Alabama in  the  corporate  limits  of the
 City of Saraland. The  5.1 acre site is about eleven miles north of
 Mobile,  Alabama.  The  Redwing Site is bounded to the east  by U.S.
 Highway 43 and a skating rink.   On the south it is  bounded by a
 United Gas Pipe Line easement.  A residential development is south
 of  the pipe  line easement.   The  Redwing  Site is bounded  on the
 north by a trailer  park,  and on  the west by an undeveloped lot.

 Statement of  Basis  and Purpose

 This decision document presents the  selected  remedial action for
 the Redwing  Site in Saraland,  Mobile County, Alabama,  which was
 chosen in accordance with the Comprehensive Environmental Response
 Compensation   and  Liability . Act   (CERCLA) , . as  amended  by  the
 Superfund Amendments  and Reauthorization Act  (SARA), and,  to the
 extent practicable,  the National  Oil  and Hazardous  Substances
 Polluticn Contingency  Plan (NCP).  This decision is  based  on the
 administrative record  for this site.

 The State of  Alabama concurs with the selected remedy.

 Assessment of the Site

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

 Description of the  Selected Remedy

 The Major components of the remedy are:

 •     Excavation of  sludge,  sediments,  and contaminated  soils.

 •     Off-site treatment/disposal of contaminated soils,  sediments
      and sludge.

. •     Regrading and  backfill of excavations using clean,  compacted
      fill material.

 •     Temporary and  possibly permanent  relocation of residents with
      the potential  demolition of selected apartment units.

      On-site  treatment of contaminated groundwater in  the surficial
      aquifer.  Monitoring and possible withdrawal and treatment of
      groundwater in the alluvial aquifer.  Treated groundwater will
      be discharged  to  a Publicly Owned Treatment Works  (POTW), or
      if unavailable,  to a nearby surface water body.

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This remedy  is  the only and final remedial action for the site.
The function of this remedy is  to  reduce the risks associated with
exposure to contaminated soils, sediments, and ground water.

The selected remedy will:

1.   Prevent migration of contaminated groundwater.

2.   Prevent human  exposure  to contaminated  soils,  sediments and
     sludge.

3.   Permanently reduce the toxicity of the harmful  constituents in
     all media.

4.   Prevent migration of site  contaminants via drainage pathways.

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.   However,  because treatment of the
principal threats of the  site was not found to be practicable, this
remedy does not satisfy the statutory preference for treatment as
a principal element.

Because this remedy will result in hazardous substances remaining
on-site above  health-based  levels,  a review  will  be conducted
within five years after commencement of remedial action to ensure
that the remedy continues to provide adequate protection of human
health and the environment.
Patrick M. Tobin                                  Date
Acting  Regional  Administrator

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                             TABLE OF CONTENTS


1.0  SITE NAME, LOCATION AND DESCRIPTION   	    1

2.0  SITE HISTORY AND ENFORCEMENT ACTIVITIES   	    5

3.0  HIGHLIGHTS OF COMMUNITY PARTICIPATION   	    5

4.0  SCOPE AND ROLE OF RESPONSE ACTION   	    7

5.0  SUMMARY OF SITE CHARACTERISTICS   	    8
     5.1  SITE GEOLOGY   	   10
     5.2  SITE HYDROGEOLOGY	   10
     5.3  AREA DRINKING WATER SOURCES  	   11
     5.4  SUMMARY OF SITE CONTAMINATION	   11
          5.4.1     CHEMICALS DETECTED DURING THE SITE  INVESTIGATION   12
          5.4.2     CHEMICALS DETECTED IN GROUNDWATER  	   12
          5.4.3     SURFACE WATER PATHWAY INVESTIGATION  	   12
          5.4.4     AIR PATHWAY INVESTIGATION	   24
     5.5  FATE AND TRANSPORT   	   24
     5.6  SOURCE AREAS OF CONTAMINATION  	   28

6.0  SUMMARY OF SITE RISKS   	   28
     6.1  CONTAMINANTS OF CONCERN	   32
     6.2  EXPOSURE ASSESSMENT  	   32
          6.2.1     EXPOSURE PATHWAYS  	   33
     6.3  TOXICITY ASSESSMENT: DOSE RESPONSE EVALUATION  	   46
     6.4  RISK CHARACTERIZATION	   52
     6.5  UNCERTAINTY ANALYSIS   	   53
     6.6  HUMAN HEALTH SUMMARY   	   56
     6.7  ENVIRONMENTAL EVALUATION   	   56
          6.7.1     UNCERTAINTY ANALYSIS   	   57
     6.8  RISK ASSESSMENT SUMMARY	   57
     6.9  CHEMICALS OF CONCERN AND CLEANUP LEVELS  	   53
     6.10 CONCLUSION   	   58

7.0  DESCRIPTION OF ALTERNATIVES   	   61
     7.1  ALTERNATIVE No. 1	   61
     7.2  ALTERNATIVE No. 2	   61
     7.3  ALTERNATIVE No. 3	   62
     7.4  ALTERNATIVE No. 4	   63
     7.5  ALTERNATIVE No. 5	   64
     7.6  ALTERNATIVE No 6   	   64
     7.7  ARARS AND TBCS	   66

8.0  SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES   	   70
     8.1  THRESHOLD CRITERIA   	   72
     8.2  PRIMARY BALANCING CRITERIA   	   73
     8.3  MODIFYING CRITERIA   	   74

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9.0  THE SELECTED REMEDY  	    15




10.0 STATUTORY DETERMINATIONS	    g-,




11.0 DOCUMENTATION OF  SIGNIFICANT CHANGES  	    81




APPENDIX A   	     i




APPENDIX B   	
                                     11

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                               LIST OF TABLES

   Table                                                              Page

TABLE I   - GEOLOGICAL  STRATA	   10

TABLE 2A  - RESULTS  FROM ORGANIC  CHEMICAL ANALYSIS OF SLUDGE   ...   14

TABLE 2B  - RESULTS  FROM INORGANIC CHEMICAL ANALYSIS OF BLACK SLUDGE
            MATERIAL  	   16

TABLE 3   - REDWING  SITE:   SUMMARY OF CHEMICALS DETECTED DURING
            REMEDIAL INVESTIGATION  	   17

TABLE 4   - REDWING  SITE:  SUMMARY OF ANALYSIS OF THE ALLUVIAL AQUIFER 23

TABLE 5   - REDWING  SITE:   ORGANIC AND INORGANIC CONSTITUENTS
            DETECTED IN DITCH SEDIMENTS 	   25

TABLE 6   - AREAS AND VOLUME  ESTIMATES FOR SOURCE MATERIAL (INCLUDES
            SLUDGE)	   26

TABLE 7A  - CHEMICALS OF POTENTIAL CONCERN FOR SOILS,  DITCH,
            SEDIMENTS,  AND TAR-LIKE MATERIAL (SLUDGE)   	   33

TABLE 7B  - CHEMICALS OF POTENTIAL CONCERN IN GROUNDWATER	   34

TABLE 8A  - SURFACE  SOIL AND  SEDIMENTS RME CONCENTRATIONS	   36

TABLE 8B  - GROUNDWATER RME CONCENTRATIONS   	   36

TABLE 9   - EXPOSURE ASSUMPTIONS  FOR U/BK MODEL	   39

TABLE 10  - SUMMARY  OF  USEPA  ASSUMPTIONS   	   40

TABLE 11  - SUMMARY  OF  NON-USEPA  ASSUMPTIONS  	   41

TABLE 12  - GENERIC  EXPOSURE  ASSUMPTIONS   	   42

TABLE 13  - SPECIFIC EXPOSURE SCENARIO ASSUMPTIONS FOR THE RME
            RECEPTOR	   43

TABLE 14  - REFERENCE DOSES,  CONCENTRATIONS,  AND CANCER SLOPE FACTORS 47

TABLE 15  - TOXICITY EQUIVALENCY  FACTORS  (TEFs)  FOR POLYNUCLEAR
            AROMATIC HYDROCARBONS (PAHs)   	   52

TABLE 16  - SUMMARY  OF  PATHWAY SPECIFIC CARCINOGENIC RISKS   ....   54

TABLE 17  - SUMMARY  OF  PATHWAY SPECIFIC TOTAL HAZARD INDICES (NON-
            CARCINOGENIC RISKS)	   55
                                     111

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TABLE 18  - CLEANUP LEVELS  FOR SUBSURFACE SOIL  	   58




TABLE 19  - CLEANUP LEVELS  FOR SURFACE SOIL AND SEDIMENTS	   59




TABLE 20  - CLEANUP LEVELS  FOR GROUNDWATER	   60




TABLE 21A - ACTION-SPECIFIC FEDERAL  ARARS	   67




TABLE 2IB - CHEMICAL-SPECIFIC FEDERAL ARARS	   68




TABLE 21C - STATE OF ALABAMA ARARS   	   69




TABLE 22A - SURFACE SOIL AND SEDIMENT EXCAVATION LEVELS	   76




TABLE 22B - SUBSURFACE SOIL EXCAVATION LEVELS	   77
                                     IV

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                                LIST OF FIGURES




    Figure




FIGURE 1 -   SITE LOCATION   	




FIGURE 2 -   AREA LAYOUT   	




             SITE LAYOUT   	




             OLD TERMINAL LAYOUT   	




             LOCATION OF SOURCE AREAS  	




             CURRENT SITE PROPERTY AND CONTAINMENT LEVEE




             SOURCE AREAS  	
FIGURE 3 -




FIGURE 4 -




FIGURE 5 -




FIGURE 6 -




FIGURE 7 -
FIGURE 8 .-  'DEPTHS OF SLUDGE (TAR-LIKE MATERIAL)
Paae



   2




   3



   4



   6




   9




  13




  29



  30
                                       v

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                         Decision Summary
                        Record of Decision
                 Redwing Carriers Inc.  (Saraland)
                        Saraland, Alabama

1.0  .   SITE NAME,  LOCATION AND DESCRIPTION

The Redwing Carriers, Inc.  (Saraland) Site  ("Redwing Site")
comprises 5.1 acres and is located at 527 U.S. 43 in the City of
Saraland, Mobile County, Alabama.  Currently, thirteen (13)
buildings which comprise the office and resident living units of
the Saraland Apartment complex are built on the Redwing Site.
The property is bounded to the north by Cook's Mobile Home Park
(containing approximately 53 mobile homes), to the south by
private residences on Craig Drive, to the west by a wooded area
and private residences on Pierce Street, and to the east by. an
indoor roller skating rink and U.S. Highway 43.  Figure 1 shows
the location of the Redwing Site.

Concrete sidewalks are between and around the apartment buildings
and along the north side of the office building.  A paved drive
and parking area surrounds the buildings' units and provides
access from U.S. Highway 43 east of the complex.  Two concrete
lined drainage ditches run parallel to the southern and eastern
property lines of the apartment complex.  The southern ditch
converges with the eastern ditch at the southeast corner of the
Redwing Site.  About 220 feet north of the southeast corner,  the
eastern ditch turns east and connects to a drainage ditch running
parallel with U.S. Highway 43 at the entrance to the complex.  A
third drainage ditch runs along the northern property line.  This
ditch is unlined, but has a grass cover.  This northern ditch
also joins with the Highway 43 drainage ditch located at the
complex entrance.  A United Gas Pipe Line easement also parallels
the northern side of this ditch.  In the playground of the
apartment complex are a slide and swing used by children.

Storm water runoff drains into ditches on the north, south and
east borders of the property.  This ditch system empties into a "
drainage ditch parallel to Highway 43 and leads to Norton Creek
approximately 1/2 mile from the Redwing Site.  Wetlands are
located within a 3 mile radius.

On-site Demographics

The Redwing Site's 60-unit apartment complex houses approximately
160 residents.  Eighty to ninety of the residents are
preschool-age or elementary school-age children who frequently
play in the yard surrounding the apartments.  Figures 2 and 3 are
site maps which show the current layout of  the property.

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The WCM GROUP. Inc. -
                       FIGURE - 1

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the WCM GROUP. Inc.

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2.0     SITE  HISTORY AND  ENFORCEMENT  ACTIVITIES

From 1961 to 1971, Redwing Carriers,  Inc.  (Redwing), a trucking
company, used the Redwing Site as a terminal for cleaning,
repairing and parking its fleet of trucks.  The firm transported
a variety of substances,  including asphalt, diesel fuel,
chemicals and pesticides from local plants along U.S. Highway 43
North.  During cleaning,  untreated substances were released to
the ground.  Figure 4 depicts the general condition of the
Redwing Site property layout during Redwing's operations.

In 1971 Redwing sold the property to Harrington Inc. which' in
turn sold the property to Apartments, Inc. on December 22, 1971.
On March 26,  1973, Apartments Inc. sold the property to Saraland
Apartments Ltd.  The Saraland Apartments were built on the
Redwing Site in 1973.

In 1984, The Alabama Department of Environmental Management
(ADEM) investigated residents' complaints about a tar-like sludge
oozing to the surface at numerous locations.  In 1985, EPA
conducted initial studies in which high concentrations of
1,2,4-trichlorobenzene and naphthalene were detected in the soil
and in leachate coming from the sludge.

EPA sent notice letters to potentially responsible parties (PRPs)
in 1985.  EPA entered into an Administrative Order on Consent
(AOC)  on July 8,  1985 with Redwing.  Under the order, Redwing was
required and continues to periodically inspect the site and
remove any visible sludge on the surface.

The Redwing Site was proposed for listing on the National
Priorities List (NPL) in 1988 and finalized in February 1990.  In
June 1990, Redwing Carriers Inc. entered into an Administrative
Order on Consent with EPA to conduct the Remedial
Investigation/Feasibility Study (RI/FS) to determine the nature
and extent of contamination at the site, to evaluate the
associated risks,  and to evaluate alternatives for eliminating
those threats. Redwing, under EPA's oversight, began field
activities for the first phase of the remedial investigation in
January 1991. The RI/FS was completed in July of 1992.


3.0     HIGHLIGHTS OF COMMUNITY PARTICIPATION

All basic requirements for public participation under CERCLA
sections 113Ck)(2)(B)(i-v) and 117 were met in the remedy
selection process.  Because the local community has been very
interested and involved in the Redwing Site status during the
removal and the remedial activities at this site, community
relations activities remained an important aspect throughout the
RI/FS process.

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3
Q
m
 •
.*

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The community relations program at the Redwing Site was designed
to maintain communication between the residents in the affected
community and the government agencies conducting remedial
activities at the Redwing Site.  Frequent communication with on-
site residents and local officials has been maintained as a
priority.  Special attention has been directed toward keeping the
community informed of all study results.  Meetings were held with
Saraland city officials and EPA staff prior to the initiation of
the RI/FS.  Prior to approval of the RI/FS Workplan, EPA
officials met with the community at an availability session in
December 1990 to inform residents of EPA's intentions and to
obtain input concerning sampling locations and health and safety
procedures.

Once the first phase of the RI/FS was complete, EPA met with the
community again in August 1991 to present the Preliminary Site
Characterization Summary which detailed the results of the first
phase of the investigation.  EPA also discussed the rationale for
the subsequent sampling investigation, Phase II.  On August 11,
1992 after the finalization of the Remedial Investigation Report
and the completion of the Draft Feasibility Study, EPA presented
its preferred remedy for the Redwing Site during a public meeting
at the Saraland Civic Center, 731 Mae Street, Saraland, Alabama.
The 30-day public comment period began on August 1, 1992 and was
extended through September 29, 1992 pursuant to requests from the
public.  A copy of the Administrative Record upon which the
remedy was based, is lo'cated at the Saraland Public Library at
111 Saraland Loop, Saraland Alabama, 36571 and extra copies of
the study were provided to a community group interested in
commenting on the proposed plan.  EPA's responses to comments
which were received during the comment period are contained in
Appendix A.


4.0     SCOPE AND ROLE OF RESPONSE ACTION

This remedy is the final remedial action for the site.  The
function of this .remedy is to reduce the risks associated with
exposure to contaminated soils, sediments, ground water and
sludge.

The selected remedial alternative will address four conditions
which pose a threat to human health and the environment:

• Contaminated aroundwater in the surficial and alluvial aquifers
   (may potentially impact drinking water supplies).

• Ditch sediments along the northern, eastern and southern
  boundaries of the apartment complex property (may pose a direct
  contact threat to the public health).

• Sludge in the upper five feet of on-site soils  (presents a

                                7

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  continuing direct contact threat to the public health).

• Sludge and contaminated subsurface soils  (present a continuing
  source of contamination to the surficial aquifer).

Groundwater at the Redwing Site has been contaminated by the
sludge and contaminated subsurface soils.  Figure 5 shows  the
areas where the sludge/contaminated soil have been encountered.
These areas correspond to the locations where the highest
concentrations of contamination has been found in the surficial
aquifer.  This is the principal threat posed by conditions at the
site.

Pathways of exposure include:

• Ingestion of contaminated soil, sediments, and sludge

• Denr.-.-". contact with contaminated soil/sediments/sludge and
  potential absorption of contaminants

• Ingestion of contaminated groundwater

• Inhalation of vapors from volatile constituents contained in
  the contaminated media.

• Migration of site related contaminants to off-site areas via
  drainage pathways.

The major components of the remedy are:

• Excavation of sludge, contaminated soils and sediments.

• Off-site materials treatment/disposal.

• Receding and backfill of excavations using clean compacted
  fill material.

• Temporary and possibly permanent relocation of residents with
  the potential demolition of selected apartment units.

• On-site treatment of contaminated groundwater in the surficial
  aquifer.  Monitoring, possible withdrawal and treatment  of
  groundwater in the alluvial aquifer.  Treated groundwater will
  be discharged to a Publicly Owned Treatment Works (POTW),  or if
  unavailable, to a nearby surface water body.


5.0     SUMMARY OF SITE CHARACTERISTICS

-------
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                                                                      S 89-46' W.  302.7S1
                                               FIGURE - 5

-------
5.1
SITE GEOLOGY
The Redwing Site geology was determined from regional geological
information and from site-specific data gathered during the
Remedial Investigation.  The Redwing Sit^ is situated on fill
soils overlying He . ocene and possibly Pleistocene alluvium.  Four
generalized strat:. ..raphic units have been defined as in Table I
below.
TABLE 1 - GEOLOGICAL STRATA
Stratum
I
II
III
IV
Approximate
Depth Range
(feet)
0.0 - 6.0
1.0 - 12.5
4.0 - 29.5
8.0 - 40.0 +
Description
Fill: Clayey to silty sand.
Clayey to silty sand with
sandy clay and silt lenses.
Clay and sandy to silty clay
with few silty sand lenses.
Sand and silty to clayey sand
with occasional clay lenses.
Details regarding the regional and site geology are contained in
the RI Report.
5.2
SITE HYDROGEOLOGY
The primary aquifer underlying the Redwing Site is a group of
alluvial and terrace deposits ranging in thickness from a thin
veneer to more than 150 feet and consisting of fine to
coarse-grained sands, gravel, silts, sandy clay and organic
material.  The groundwater in the vicinity of the Redwing Site is
approximately 10 feet below land surface.  The Redwing Site is
underlain by strata that comprise the Alluvial aquifer of Mobile
County.  Three distinct hydrogeologic units were identified from
four strata underlying the Redwing Site.  The designations
assigned to these three units are as follows: (1) the Surficial
Aquifer  (upper sands);  (2) a Low Permeability Unit and (3) the
Alluvial Aquifer  (lower sands).  Groundwater in the aquifers
beneath the Redwing Site have been classified as Class IIB for
the surficial groundwater and Class IIA for the alluvial aquifer.
Class IIB groundwater is a potential drinking water source
although the groundwater may not be currently used as such.
Class IIA groundwater is a current source of drinking water.
                                10

-------
Watertable elevations indicate that groundwater flow within the
Surficial Aquifer is toward the south.  This southward flow
coincides with the southward slope of the underlying Stratum III
surface.

The low permeability hydrogeological unit is represented by
Stratum III as was described in Table 1.

The third hydrogeologic unit encountered at the Redwing Site is
defined by the lower sands designated as Stratum IV.  Stratum IV
has been designated the Alluvial Aquifer Unit.  Groundwater in
the Alluvial Aquifer is generally first encountered at.depths 11
feet to 19 feet.  Groundwater flow in the Alluvial Aquifer is in
a westerly direction.  This flow direction is almost
perpendicular to the watertable groundwater flow in the surficial
Aquifer.


5.3    AREA  DRINKING WATER SOURCES

Drinking water'for residents of Saraland is supplied by the City
of Saraland Water Department, which obtains its water supply from
wells located north of the Redwing Site.  These three wells are
located between 5000 and 7500 feet north of the Redwing Site.
The depths range from 95 feet to 124 feet below ground surface.
An additional well is located about 1400 feet southeast of the
Redwing Site and extends to a depth of 98 feet.  A well inventory
survey was conducted to identify private wells within a one mile
radius of the Redwing Site and identified 124 private wells in
the area.  Seventeen of the wells are currently being used.  Two
of the wells have their last documented use recorded as 1987.
The uses range from drinking water to water for gardening.  The
wells range in depth from 15 to 140 feet. The complete results of
the survey are contained in the Remedial Investigation report.


5.4    SUMMARY  OF  SITE  CONTAMINATION

The Remedial Investigation was initiated in December 1990.  The
RI sampling,  conducted in 1991 and 1992, focused on areas related
to former terminal operations.  Figure 6 shows a containment
levee (thought to be the residuals disposal area)  overlain by the
current site features.  During the truck washing operations,
chemical residue and other contaminants were released from the
trucks onto the ground and into the drainage ditches and levee
areas on the property.  Many of the contaminants were likely
diluted and washed away during storm events, however, many of
them adhered to the asphalt which was also deposited across the
property during maintenance operations.  The asphalt was
contained primarily in the levee area with overflow going to the
ditches.   Many of the chemicals from the truck washing affixed
themselves to the asphalt.  This resulted in the sludge that we

                                11

-------
                                                       FIGURE - 6
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-------
 currently encounter at  the Redwing Site.   Tables 2A and 2B
 contain the results from analysis  of the  sludge.  The sludge is
 present at the Redwing  Site in two forms:  (1)  surface seeps  at
 194 locations since 1985 (see Figures 5 and 6),  and (2)  sludge
 mixed with soil found in 15 samples across the Redwing Site.
 There is a direct  relationship between constituents found in the
 soil and in the surficial groundwater.  '


 5,4.1  CHEMICALS DETECTED DURING THE SITE INVESTIGATION

 During the investigation,  39 soil  borings  were collected with a
 total of 123 separate soil samples being  analyzed.   The
 substances found most frequently at concentrations  above cleanup
 levels fall into three  major  categories:   1)  pesticides and
 herbicides; 2)  Volatile organic compounds  (VOCs) and 3)
 Polycyclic Aromatic Hydrocarbons (PAHs).

 These substances were found in soils,  ditch sediments,  and
 groundwater across the  Redwing Site.  The  highest levels of
 contamination were detected in the southern and eastern portions
 (the location of the former containment levee  used  by Redwing)
-*and across areas of former terminal operations.   Inorganic
 substances, which  may occur in nature in  significant levels,  were
 also detected in soils,  sludge and groundwater.


 -5.4.2  CHEMICALS DETECTED IN GROUNDWATER

 Substances moving  from soil and the sludge have contaminated
 groundwater in the surficial,  or shallow,  aquifer.   Highest
 .groundwater contaminant concentrations are under the eastern half
 of the Redwing Site,  but the upper aquifer has been affected
 under most of the  Redwing Site.  Limited movement of contaminants
 to the alluvial (lower)  aquifer has occurred,  but at much lower
 levels.

 Table 3 illustrates the migration  of contaminants from "the source
 areas to the surficial  groundwater and alluvial sands.   The
 groundwater in the alluvial aquifer was found  to be contaminated
 in limited areas with some site related constituents.  Table 4
 illustrates the result  of the alluvial aquifer sampling.


 5.4.3   SURFACE  WATER PATHWAY  INVESTIGATION

 Storm water which  contacts surface soils,  and  sludge that has
 seeped to the surface,  drains into on-site ditches  resulting in a
 possible exposure  pathway.  The northern  ditch is unlined but
 covered with grass.  The southern and eastern  ditches are now
 concrete-lined but were unlined when Redwing operated at the
 Redwing Site.  Therefore, the study of the ditches  extended  to

                                 13

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TABLE 2A - RESULTS FROM ORGANIC CHEMICAL ANALYSIS OF SLUDGE
COMPOUND
1,1,1 TRICHLOROETHANE
1,2,4 -TRICHLOROBEN2ENE
2-BUTANONE (MEK)
2 -CYCLOHEXEN- 1 -OL
2-HEPTANONE
2-HEXANONE
2 -METHYLNAPHTHALENE
2-PENTANONE, 4-HYDROXY-4-METHYL
2-PROPANOL
4 -METHYL - 2 - PENTANOl ;Z
4,4' -DDD
4, 4 '-DDE
4, 4 '-DDT
ACENAPHTHENE
ACETONE
ALDRIN
ALPHA-BHC
ALPHA-CHLORDANE
ANTHRACENE
BENZENE
B El -:,: . A ) ANTHRACENE
BENZO (A) PYRENE
BENZO (B) FLUORANTHENE
BENZO (K) FLUORANTHENE
BENZO- ( G , H , I ) PERYLENE
BETA-BHC
BIS ( 2-ETHYLHEXYL) PHTHALATE
BUTYLATE
CACARBAMOTHOIC ACID.DIPROYL
CARBON DISULFIDE
CHLOROFORM
NO OF TIMES
DETECTED
1
2
3
1
1
2
3
8
2
1
3
1
4
2
7
1
1
12
4
3
5
3
5
1
2
1
4
8 •
1
3
1
RANGE OF CONCENTRATIONS DETECTED
tig /kg
3
4,000 - 18,000
13 - 120
180
48
11 - 27
2,500 - 5,200
1,900 - 100,000
12-36
15
0.1 - 6.8
0.29
0.48 - 11
2,600 - 4,600
54 - 610
0.86
1.1
762 - 19,100
200 - 7,300
4-48
160 - 7,2C.
920 - 3,200
280 - 7,200
1,700
610 - 880
6.4
58 - 200
450 - 51,000
4,900
5-24
4
14

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TABLE 2A - RESULTS FROM ORGANIC CHEMICAL ANALYSIS OF SLUDGE
COMPOUND
CHRYSENE
CYCLOATE
CYCLOHEXANE, DICHLORO
CYCLOHEXANOL , CHLORO
DELTA-BHC
DIBENZOFURAN
DIELDRIN
ENDRIN
ENDRIN KETONE
EPTC
ETHYLBENZENE
FLUORANTHENE
FLUORENE
GAMMA-BHC (LINDANE)
HEPTACHLOR EPOXIDE
INDENO (1,2,3 -CD) PYRENE
METHOXYCHLOR
METHYLENE CHLORIDE '
MOLINATE
NAPHTHALENE
NAPHTHALENE, 1 -METHYL
NAPHTHALENE ,2,3 -DIMETHYL
PEBULATE
PHENANTHRENE
PYRENE
SULFER, MOL(S8)
TOLUENE
VERNOLATE
XYLENE
NO OF TIMES
DETECTED
5
2
1
1
1
2
2
2
1
4
2
6
4
1
1
2
1
3
2
2
1
1
7
5
6
6
3
7
3
RANGE OF CONCENTRATIONS DETECTED
Hg/kg
160 - 6,000
6.6 - 10
670
1,400
0.23
2,200 - 6,800
1.1 - 3.4
3.3 - 11
17
39 - 1,900
18 - 120
200 - 23,000
2,300 - 12,000
0.12
1.7
710 - 1,300
13
5-48
18 - 21
3,900 - 13,000
9,900
5,600
25 - 9,800
850 - 33,000
ISO - 12,000
1,600 - 100,000
30 - 52
43 - 130,000
5 - 480
15

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TABLE 2B - RESULTS FROM INORGANIC CHEMICAL ANALYSIS OF BLACK
SLUDGE MATERIAL
CHEMICAL
ALUMINUM
ARSENIC
BARIUM
BERYLLIUM
CADMIUM
CALCIUM
CHROMIUM .: II/VI)
COBALT
COPFSR
IRON
LEAD
MAGNESIUM
MANGANESE
MERCURY
NICKEL
POTASSIUM
SELENIUM
SODIUM
VANADIUM
ZINC
NO OF TIMES
DETECTED
12
6
11
2
2
12
11
1
11
12
11
12
10
7
6
5
3
12
12
12
RANGE OF CONCENTRATIONS INORGANIC CHEMICALS
DETECTED (mg/kg)
762 - 19,100
0.71 - 3.3
9.1 - 80,9
0.39 - 0.63
2.2 - 9.5
59.1 - 27,100
2.7 - 51.9
2.7
1 - 23.7
204 - 9,150
4.2 - 316
11.1 - 361
2.1 - 372
0.15 - 1.9
3 - 30.1
199 - 1,960
0.62 - 1.6
169 - 12,900
1.8 - 30.6
2.2 - 97.7
16

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TABLE 3 - REDWING SITEt SUMMARY OF CHEMICALS DETECTED DURING REMEDIAL INVESTIGATION
* - INDICATES TENTATIVELY IDENTIFIED
COMPOUNDS
6 - INDICATES ORGANIC COMPOUND WHICH
WAS ALSO DETECTED IN THE ALLUVIAL
GROUNDWATER
CHEMICALS
1.1,1 TRICHLOROETHANE
1,2-CYCLOHEHANEDIOL *
1 . 2 . 4-TRICHLOROBENZENE
1,4 DICHLOROBENZENE
2(3HI-FURANONE,DIHYDRO-4,5 •
2-BUTANONE (MEKI
2-CYCLOHEXEN-l-OL •
2-CYCLOHEXEN-l-ONE •
2-HEPTANONE •
2-HEXANONE
2-HEXANONE, 5-METHYL *
2-METHYLNAPHTHALEME
2-METHYLPHENOL
2-PENTANONE.4-HYDROXY 4 • METHYL '
2-PROPANOL •"
2,4-D
2 , 4 -DIMETHYLPHENOL
2,4,5-T
2,5 CYCLOHEXADIENE-l, 4-D10NE *
4-METIILY-2-PEHTANONE
4 METHI.YPIIF.riOL
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE VADOSE
ZONE ( 0 ' - 2 ' 1
RANGE OF
CONCENTRATIONS
DETECTED(ng/kg)
ND
NO
290 - 18,000
ND
ND
95
ND
ND
ND
4 -64
1,300 -2,200
4,300 - 4,700
ND
5.700 - 170,000
190
ND
ND
20
NO
15 - 19
IIU
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE
SATURATED ZONE
12'- 81 )
RANGE OF
CONCENTRATIONS
DETECTED(Hg/kg)
3
ND
64 - 3,000
190
ND
8 - 13
180
ND
14
5 - 29
ND
44 - 2,600
ND
1,200 - 130,000
12 - 13
9.2
ND
NO
620
8 - 27
77
RESULTS FROM
CHEMICAL ANALYSIS OF
SURFICIAL
GROUNDWATER
RANGE OF
CONCENTRATIONS
DETECTED IHg/1)
ND
13
ND
ND
79
12 - 72
8 - 12
4.7
ND
4-16
ND
ND
120
24
ND
14
20
9.6
20
16
12 790
RESULTS FROM
CHEMICAL ANALYSIS
OF ALLUVIAL SANDS
RANGE OF
CONCENTRATIONS
DETECTED (|lg/kg!
HD
ND
ND
ND
ND
MD
ND
ND
MD
ND
210 - 7SO
I ID
ND
3, SOO - 21,000
32 - 44
8.2
ND
3.4
no
MD
HD
17

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TABLE 3 - REDWING SITE: SUMMARY OF CHEMICALS DETECTED DURING REMEDIAL INVESTIGATION
* - INDICATES TENTATIVELY IDENTIFIED
COMPOUNDS
6 - INDICATES ORGANIC COMPOUND WHICH
WAS ALSO DETECTED IN THE ALLUVIAL
GROUNDWATER
CHEMICALS
4. t '-ODD
t, 4 '-DDE
4, 4 '-DDT "
ACENAPHTHENE
ACETONE b
ALDRIN
ALPHA- BHC
ALPHA-CHLORDANE
ALUMINUM
ANTHRACENE
ARSENIC
BARIUM
BENZENE
BENZO ( A ) ANTHRACENE
BENZOIAIPYRENE
BENZO ( B ) FLUORANTHENE
BENZO ( K 1 FLUORANTHENE
BENZO- (G,H, IIPERYLENE
BENZOIC ACID '
BENZOIC ACID-DICHLORO *
BERYLLIUM
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE VADOSE
ZONE ( 0 ' - 2 ' 1
RANGE OF
CONCENTRATIONS
DETECTED |(lg/ kg)
12 - 65
2 - 5.8
16 - 74
2,700
3 - 230
0.36 - 10
1.1 - 4.7
4.5 - 14
(1,850 - 19, 100)E'
200 - 2,000
1,400 - 3,600
10,800 - 80,900
4
1,000 - 1,800
920 -1,200
3000
1,700
100 - 610
ND
ND
610
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE
SATURATED ZONE
(2'- 8')
RANGE OF
CONCENTRATIONS
DETECTEDIHg/kgl
.36 - 17
3.8 - 5.8
1 - 25
170 - 1,400
30 - 270
0.86 - 15
2 - 3.2
6.9 - 19
(1,740 - 10,400)E'
240 - 2,100
1,300 - 3,500
9, 100 - 56,200
4
6,900
ND
7,400
ND
ND
ND
ND
260 - 300
RESULTS FROM
CHEMICAL ANALYSIS OF
SURFIC1AL
GROUNDWATER
RANGE OF
CONCENTRATIONS
DETECTED ((lg/1)
ND
ND
0.86
ND
550 - 4,400
.011 - .47
0.044 - 0.15
ND
(8.04 - 229IE'
ND
4 - 22.6
231 - 1,100
ND
ND
ND
ND
ND
ND
16 - 66
5
3.9 - 9.5
RESULTS FROM
CHEMICAL ANALYSIS
OF ALLUVIAL SANDS
RANGE OF
CONCENTRATIONS
DETECTED (pg/kgl
ND
ND
4.5
ND
25 240
2.6
ND
210 - 750
(257 - 2,430) E'
NO
(1.3 - 1.5) F.1
(5.3 - 13.1-:.
ND
ND
ND
ND
ND
ND
ND
ND
430 - 440
18

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TABLE 3 - REDWING SITES SUMMARY OF CHEMICALS DETECTED DURING REMEDIAL INVESTIGATION
* - INDICATES TENTATIVELY IDENTIFIED
COMPOUNDS
" - INDICATES ORGANIC COMPOUND WHICH
WAS ALSO DETECTED IN THE ALLUVIAL
GROUNDWATER
CHEMICALS
BETA - BHC
BICYCLO(2,2, DHEPTAN-2-ONE •
BIS(2-ETHYLHEXYL)PHTHALATE "
BUTYLATE b
CADMIUM
CALCIUM
CARBAMOTHIOJC ACID, DIPROPYL •
CARBON TETRACHLOR IDE
CARBON DISUI.FIDE
CHLOROBENZENE
CHLOROFORM
CHLOROPYRIFOS
CHROMIUM (III/VI)
CHRYSENE
CINEOLEIVANI "
COBALT
COPPER
CYANIDE
CYCLOATE b
CYCLOHEXANE(DOT) *
CYOLOHEXANECARABOXYLIC ACID *
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE VADOSE
ZONE ( 0 ' - 2 ' )
RANGE OF
CONCENTRATIONS
DETECTED (fig /kg)
6.4 - 10
ND
58 - 580
1.7 -' 30,000
2,200 - 9,500
(1,440 - 61,600)E'
4,900
110,000
5
19
100
ND
4,500 - 51,900
160 - 2,400
780 - 7,700
1,900 - 2,700
1,900 - 23,700
ND
6.6 - 10
7
HO
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE
SATURATED ZONE
<2'- 8')
RANGE OF
CONCENTRATIONS
DETECTED l(Jg/kg)
2 - 29
ND
58 - 500
2.4 - 4,900
ND
(106 - 9.490IE1
470
ND
4-9
ND
250
230
3,500 - 19,000
6,000
ND
1,500
1,200 - 27,000
1,600
3.4 - 390
ND
NO
RESULTS FROM
CHEMICAL ANALYSIS OF
SURFICIAL
GROUNDWATER
RANGE OF
CONCENTRATIONS
DETECTED 
-------
TABLE 3 - REDWING SITEt SUMMARY OF CHEMICALS DETECTED DURING REMEDIAL INVESTIGATION
• - INDICATES TENTATIVELY IDENTIFIED
COMPOUNDS
* - INDICATES ORGANIC COMPOUND WHICH
WAS ALSO DETECTED IN THE ALLUVIAL
GROUNDWATER
CHEMICALS
CYCLOHEXANE.DICHLORO rt
CYOLOHEXANOL.CHLORO '"
CYCLOPENTANECARBOXALDEHYDE '"
CYCLOPENTANOL.2-METHLY *
DELTA -BHC "
DI-N-BUTYL PHTHALATE
DIBENZOFURAN
DICAMBA
DICHLORPROP
DIELDRIN
DIETHYLPHTHALATE
ENDOSULFAN SULFATE
ENDOSULFAN I
ENDRIN
ENDRIN ALDEHYDE
ENDRIN KETONE
EPTC b
ETHAHONE, 1- ( 3-ETHYLOXIRANYLI •
ETHYLBENZENE
FLUORANTHENE
FLIIOREtlE
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE VADOSE
ZONE 10' - 2 ' )
RANGE OF
CONCENTRATIONS
DETECTED (Jig/ kg)
ND
ND
ND
ND
ND
13
2,200
100
220
0.61 - 6.3
ND
ND
0.93
1.1 - 11
ND
2.5 - 17
5.9 - 490
ND
4 - 87
660 - 11,000
3,800 - 10.000
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE
SATURATED ZONE
(2'- 8')
RANGE OF
CONCENTRATIONS
DETECTEDIHg/kg)
200 - 850
340 - 2,500
ND
ND
.23 - IS
30
130 - 1, 100
ND
ND
1.1 - 14
390
3.8 - 19
2
1.7 - 18
3.8
3.8 - 15
1.7 - 800
480
ND
120 - 14,000
170 - 2,300
RESULTS FROM
CHEMICAL ANALYSIS OF
SURFICIAL
GROUNDWATER
RANGE OF
CONCENTRATIONS
DETECTED (flg/l)
7 - 24
13 - 140
4 - 26
230
0.04
3-4
ND
ND
ND
.012 - 1.1
ND
.02
ND
.018 - 1.5
ND
ND
.24 - 1.9
ND
ND
ND
NU
RESULTS FROM
CHEMICAL ANALYSIS
OF ALLUVIAL SANDS
RANGE OF
CONCENTRATIONS
DETECTED (|ig/kgl
ND
ND
ND
ND
ND
ND
ND
ND
ND
1.9
ND
ND
ND
5
ND
ND
ND
ND
ND
NO
ND
20

-------
TABLE 3 - REDWING SITE: SUMMARY OF CHEMICALS DETECTED DURING REMEDIAL INVESTIGATION
* - INDICATES TENTATIVELY IDENTIFIED
COMPOUNDS
* - INDICATES ORGANIC COMPOUND WHICH
WAS ALSO DETECTED IN THE ALLUVIAL,
GROIJNDWATER
CHEMICALS
GAMMA-BHC ILINDANE)
GAMMA-CIILORDANE
HEPTACHLOR
IIEPTACHLOR EPOXIDE
HEXADECANOIC ACID *
HYDROCARBON COMPOUND *
IHDENO ( 1 , 2 , 3 , -CD) PYRENE
IRON
LEAD
MAGNESIUM
MAIIOAIIKSE
MERCURY
METHOXYCHLOR
METHYLENE CHLORIDE
MOLINATE
NAPHTHALENE
NAPHTHALENE 1 -METHYL * *
NAPHTHALENE. 2. 3-DIMETHYL '
NICKEL
PEBULATE
PHENANTHREHE
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE VADOSE
ZONE ( 0 ' - 2 ' )
RANGE OF
CONCENTRATIONS
DETECTED (Hg/ kg)
2.5
2.1 - 9.9
1.4
.58 - 5.3
500
ND
710
(760 - 11, 900 IE1
11.13 - 33.4IE1
(100 - 2. 150 IE'
(100 - 2, 150 IE'
120 - 1,400
4-1
4 - 89
21
3,900
9,900
5,600
4,900 - 30, 100
1.6 - 9, HOO
B50 - 15,000
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE
SATURATED ZONE
12'- 8' )
RANGE OF
CONCENTRATIONS
DETECTED (Jig/ kg 1
.12 - 16
2 - 9.6
1 - 15
.53 - 2
ND
970
ND
(2,080 - 15,400)E'
(3.9 - 42.8IE'
(56.3 - 568) E1
(2.5 - 259IE1
130 - 1,200
.25 - 34
3 - 180
18
48 - 2, 100
ND
ND
4,700 - 22,500
7.7 - 1,300
160 - 6,500
RESULTS FROM
CHEMICAL ANALYSIS OF
SIJRFICIAL
GHOUHDWATER
RANGE OF
CONCENTRATIONS
DETECTED (Jig/ 11
.01 - 0.7
ND
0.018 - 0.51
ND
ND
ND
ND
(8.63 - 937) E'
3.4 - 162
(4.73 - 45.6IE'
(757 - 1.890IE1
ND
ND
330 -650
0.14
16
ND
36.2 - 301
28.7 - 301
0.61
HD
RESULTS FROM
CHEMICAL. ANALYSIS
OF ALLUVIAL SANDS
RANGE OF
CONCENTRATIONS
DETECTED (pg/kg)
7.7 - 7.8
ND
3.4
ND
ND
ND
ND
(385 - 3.6001E'
760 - 3,000
(40.3 - 348IE'
(3.1 - 9 . 4 ) E'
ND
ND
ND
ND
ND
ND
ND
27, 100
HD
HD
21

-------
TABLE 3 - REDWING SXTEi SUMMARY OF CHEMICALS DETECTED DURING REMEDIAL INVESTIGATION
• - INDICATES TENTATIVELY IDENTIFIED
COMPOUNDS
* - INDICATES ORGANIC COMh'i'lID WHICH
WAS ALSO DETECTED IN THE ALLUVIAL
GROUNDWATER
CHEMICALS
PHENOL
PHENOL-DIMETHYL *
POTASSIUM
PYRENE
SELENIUM
SODIUM
SULFUR, MOLIS8) * b
TETRACHLOROETHANE
TOLUENE
VANADIUM
t'1 VERNOLATE
XYLENE
ZINC
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE VADOSE
ZONE ( 0 ' - 2 ' )
RANGE OF
CONCENTRATIONS
DETECTED (Jig /kg)
NO
ND
(206 - 334IE1
160 - 8,400
710 - 1,600
(37.1 - 3,600)EJ
190 - 44,000
1,600
3-46
8,400 - 49,900
2 - 26,000
5 - 990
1,340 - 97,700
RESULTS FROM
CHEMICAL ANALYSIS OF
SOILS IN THE
SATURATED ZONE
12'- 9'|
RANGE OF
CONCENTRATIONS
DETECTED (fig /kg)
ND
ND
199,000
1000 - 11,000
890
(SB. 2 - 5.4301E'
380 - 100,000
ND
30
5,700 - 31,900
49 - 8,400
5
4,300 - 207,000
RESULTS FROM
CHEMICAL ANALYSIS OF
SURFICIAL
GROUNDWATER
RANGE OF
CONCENTRATIONS
DETECTED (Hg/1)
520
61
J-.U - 25,500
ND
3.7
(37.8 - 2.370IE1
6 - 96
ND
4
16.5 - 580
1.1 - 140
ND
187 - 739
RESULTS FROM
CHEMICAL ANALYSIS
OF ALLUVIAL SANDS
RANGE OF
CONCENTRATIONS
DETECTED 1 fig /kg)
ND
ND
254,000
ND
ND
(44.6 - 89.6IE'
230 - 4000
ND
24
4,700 - 8,400
ND
ND
2,700 - 51, 100
22

-------
TABLE 4 - REDWING SITE: SUMMARY OF
CHEMICALS
1 . 3 -DICXOLANE, 2-ETHYL-4 -MET •
2-PROPANOL '
4, 4 ''-DDT
ACETONE
ALUMINUM
ARSENIC
BARIUM
BERYLLIUM
BIS i 2 -ETHYLHEXYL ! PKTHALATE
BUTYLATE
CALCIUM
CAPROLACATAM *
CHLORINATED HYDROCAR30N COM? *
CHROMIUM (III/VI;
COBALT
COPPER
CYCLOATE
CYCLOHEXANE.DICHLORO •
CYCLOHEXANOLCHLORO •
CYCLOPENTANECARBOXALDEKYDE •
DE1TA-3HC
DI-N-CCTYL PHTHALATE
E?TC
IRON
LEAD
MAGNESIUM
MANGANESE
NAPHTHALENE 1-METHYL *
NICKEL
POTASSIUM
SODIUM
SULFUR, MOLIS8) •
VANADIUM
VZKNOLATE
ZINC
ANALYSIS OF THE ALLUVIAL AQUIFER
RESULTS FROM CHEMICAL ANALYSIS
OF ALLUVIAL GROUNDWATER
RANGE OF CONCENTRATIONS
DETECTED (|lg/i)
ICO
£
.01 - .08
12 - 180
6. 350 - 42,000
4 - 29.8
98.9 - 213
1.3 - 5.2
2 - 620
0.31 - 1
13, 000 - 44,800
14 - 26
4 - 6.1
28.7 - 66.3
6.5 - 33.3
18.9 - 34.9
0.15
16 - 51
180 - 260
10 - 37
.02
29
0.12
8,850 - 166,000
16.5 - 79.9
2,830 - 9,640
27C - 479
6
21.4 - 44.3
3,480 - 9,090
10,300 - 77,400
30
15.8 - 111
0.44 - 1.8
67.4 - 324
NO. OF
DETECTS
1
i
2
8
11
7
±±
3
7
2
11
2
3
11
6
8
1
4
4
3
1
^
1
11
10
11
11
1
5
8
11
1
3
4

RESULTS FROM CHEMICAL ANALYSIS
OF BACKGROUND AlLl'VIAL
GSOUNDwATEr.
RANGE OF CONCENTRATIONS
DETECTED {(ig/i!
ND
ND
ND
180
3,780
NC
93.8
ND
ND
ND
11,500
ND
ND
21.3
5.2
14.3
ND
ND
ND
ND
ND
ND
ND
7,380
9
2,400
253
ND
ND
2,140
7, 590
ND
14.5
ND
55.3
Nc . OF
_/:..:.. . j
.•-
ND
.•::


::D

M
V"™1
''"'•
•_
ND
ND

i
;
N'D
N-
NI.'
ND
ND
I.'D
:::
i
i
^
1
t.;~
r-—.
i
i
N3
1
N"

• - INDICATES TENTATIVELY IDENTIFIED COMPOUND
23

-------
soils beneath the concrete  liners.  Contaminants  found  in  the  8
ditch samples were  similar  to  those' detected  in soils'.  Table  5
illustrates the contaminants found  in the  ditch sediments.

A ditch sample collected below the  concrete liner in the eastern
ditch contained the highest number  of compounds at the  highest
concentrations.  Lower concentrations were found  in downstream
ditch areas.

Site ditches provide only temporary habitats  for  aquatic plants
and animals.  Two water species, the arrowhead plant and
mosquitofish, were  observed after heavy rain.  The mosquitofish
would likely move downstream as ditch water dried up.   Since
contaminants in ditch sediments can move downstream and could
have moved in the past, EPA used data from on-site ditch
sediments to predict effects on plant and  animal  life in
downstream surface  water bodies.  The analysis of these data
indicates that the  highest concentrations  are presently separated
from the ditch by the concrete liner and that measurable levels
are not presently moving off-site.


5.4.4   AIR  PATHWAY INVESTIGATION

A sample of sludge  was collected and the vapor from the headspace
a:, ilyzed at temperatures 25°C and 45°C  (77  and 113 degrees
fa..renheit,  respectively).  Two volatiles  were detected at the
high temperature and one semi volatile at the  low  temperature.
Additionally, air modeling -was conducted using assumptions which
were more conservative than the above headspace analysis.  This
was done to predict risk that might be posed  if people were
breathing those contaminants in the air.   Modeling and  air
monitoring results  indicated that exposure, above Federal/State
standards, to chemicals in the air  was not likely to occur.


5.5     FATE AND  TRANSPORT

An evaluation of the potential for  transport and  likely fate of
compounds detected  during the remedial investigation consisted of
analysis of the relationships among the various media at the
Redwing Site.  This evaluation also entailed a review of the
physical and chemical data for each constituent in all
potentially affected media.  To estimate concentrations for media
and locations where no samples were collected or  over time frames
for which data is not available, estimates were made of
concentrations using environmental  fate and transport models.

Exposure pathways for modeling were (1) a  source  and mechanism of
chemical release;  (2) an environmental transport medium; (3) a
point of pot- -.tial  exposure and (4) an exposure route.   The media
evaluated foi both  present and potential future exposure were  (a)
groundwater  (alluvial and surficial); (b)   soils and seeps of
sludge; (c)  air and (d) surface water and  sediments.

Contaminants have been found primarily in  the e~  ~ern portion of
the Redwing Site and in the location of the for:   / levee.   The
contaminants are affiliated with the sludge and .  -.e soil that is

                                24

-------
TABLE 5 - REDWING SITE: ORGANIC AND INORGANIC CONSTITUENTS DETECTED IN DITCH
SEDIMENTS
• - INDICATES TENTATIVELY IDENTIFIED COMPOUNDS (TICs)
» - INDICATES ORGANIC COMPOUND WHICH WAS ALSO
DETECTED IN THE ALLUVIAL GROUNDWATER
CHEMICALS
RESULTS OF ANALYSIS
FROM BACKGROUND SOILS
RANGE OF CONCENTRATIONS
DETECTED '>g/kg!
RESULTS OF ANALYSIS Fr.C-K DITCH
SEDIMENTS
RANGE OF CONCENTRATIONS
DETECTED (pig/kg1
N'c. cf
0-i-*---S
OROANICS
1 , 1-, 1 -TRICKLOROETHANE
2-S'JTANONE (MEK)
2-CYCLOHEXEN-l-OL •
2 -METHYLNAPHTHALENE
2-PENTANONE.4-HYDROXY 4 -METHYL '
4, 4 '-ODD
4, 4 '-DDE
4, 4 '-DDT "
ACENAPHTHENE
ACETONE "
ALDP.IN
ALPHA-BHC
ALPKA-CHLORDANE
ANTHRACENE
3ENZO ( A i ANTHRACENE
EEN20 ( S } FL'JCRANTHENE
BETA - EHC
BIS ( 2 -ETHYLHEXYL ) PHTHALATE "
B'u'TYLATE b
CHRYSENE
CYCLOHEXANE.DICHLORO ' *
CYCLOHEXANOLCHLCRO •*
DELTA-BHC *
DIBENZOFURAN
DIELDRIN
ENDOSULFAN I
ENDRIN
END?. IN KETONE
ENDRIN ALDEHYDE
ETHYL3ENZENE
ETHYNS. FL'JCP.C-'
ND
8
ND
ND
ND
ND
.47 - .61
ND
ND
5 - 67
ND
ND
.38 - 1.8
ND
180
300
ND
79 - 180
ND
93
ND
ND
ND
ND
0.57
ND
ND
ND
ND
ND
ND .
8
1? - 6£
1 * f.
-t .
2,200
9,000 - 7 £,000
0.34
0.23
0.32
2,400 - 2.7CC
33 - 160
0.67 - 200
0.16
0.67 - :;
1,300
1,300
1,30:
4.8
140 - 160
120
1,300
150
1,800
18
1,500 - 1,800
C . 16
0.93
0.52
3.9
3.9
IS
7

:

;
S
1
.
J.
•)
4
^
i
;
:
1
i
i
2
^
^
i
;
:
;
•
^
;
;
i
^
-
25

-------
TABLE 5 - REDWING SITE: ORGANIC AND INORGANIC CONSTITUENTS DETECTED IN DITCH
SEDIMENTS
• - INDICATES TENTATIVELY IDENTIFIED COMPOUNDS (TICs)
» - INDICATE-- ORGANIC COMPOUND WHICH WAS ALSO
DETECTED IN THE ALLUVIAL GROUNDWATER
CHEMICALS
FL'JORAT.'THENE
FLUOP.ENE
GAMMA-BHC (LINDANE!
GAMMA-CHLORDANE
HEPTACHLOR
HEPTACHLOR EPOXIDE
•METHOXYCHLOR
METKV^ENE CHLORIDE
NAPHTHALENE
NAPTHALENE. -TRIMETHYL-
NAPHTHALENE, 2, 3 -DIMETHYL *
PEBULATE
PHENANTHRENE
PYRENE
SULFUR, MOL(S8) • "
VERNOLATE
XYLENE
RESULTS OF ANALYSIS
FROM BACKGROUND SOILS
RANGE OF CONCENTRATIONS
DETECTED (Jig/kg)
310
ND
ND
.42 - 1.3
ND
ND
ND
2-10
NC
ND
ND
ND
97
240
ND
ND
ND
INORGANICS
ALUMINUM
ARSENIC
BARIUM
CALCIUM
CHROMIUM (III/VI)
COBALT
COPPER
IRON
LEAD
MAGNESIUM
MANGANESE
MERCURY
NICKEL
POTASSIUM
254 - 4,140
ND
7.6 - 42.1
38.3 - 1,350
1.4 - 8.2
8.9
1.1 - 4.2
322 - 9,520
3.8 - 9.8
28.5 - 820
1.9 - 107
ND
7
25.8 - 396
RESULTS OF ANALYSIS ~ZCV D:~CH .
SEDIMENTS i
RANGE OF CONCENTRATIONS
DETECTED (fig/kg!
4, 500 - 7,700
2,500 - 2.SOC
0.087 - 54
0.76 - 18
0.69
1.5
2.5
7-31
5,200
9, 300
13, OOC
IS - 71
8,700 - 11,000
3,300 - 4, SOO
180 - 52,000
290 - 2,600
17 - 25
No . of
Deteccs
:,
2
;
;

1

2

:

:
2
:
;.
2
n

1,350 - 10,700
1.2 - 2.8
11.5 - 32.2
338 - 6,460
4.9 - 24.3
1.8 - 2.5
2.3 - 4.3
2,950 - 28,900
8.2 - 17.3
74.1 - 149
7.3 - 20
0.33 - 3.1
6.1
250
9
->
*3
8
c
:
5
4
5
c
=
;
1
i
26

-------
TABLE 5 - REDWING SITE: ORGANIC AND INC
SEDIMENTS
• - INDICATES TENTATIVELY IDENTIFIED COMPOUNDS (TICsl
b - INDICATES ORGANIC COMPOUND WHICH WAS ALSO
DETECTED IN THE ALLUVIAL GRCUNDWATER
CHEMICALS
SODIUM
VANADIUM
ZINC
IRGANIC CONSTITUI
RESULTS OF ANALYSIS
FROM BACKGROUND SOILS
RANGE OF CONCENTRATIONS
DETECTED (|ig/kg>
40.9 - 46.3
6-17
1.9 - 31.9
SNTS DETECTED IN
RESULTS OF ANALYS7- •'
SEDIMENTS
RANGE OF CONCENTRATIONS
DETECTED (Jig /kg!
41 - 3.500
9.4 - 29.2
17.- - 30. e
DITCH
Cv DT7CK

N£ . Of
*i
4
~
commingled with the sludge.  This combination shall be referred
to as the "source material".  Various classes of compounds were
distributed across areas of the former terminal operations.
Volatile organic compounds  (VOCs) and aromatic compounds are
generally less persistent in surficial soil and surface water.
The VOCs are most persistent in groundwater.  The semivolatile
compounds detected at the Redwing Site are found to be insoluble
in the groundwater with the exception of the phenols.  Some of
the Polycyclic Aromatic Hydrocarbons  (PAHs) are very persistent
and tend to bioaccumulate in the environment although no
significant concentrations were found in the groundwater at the
Redwing Site.

Pesticides and herbicides detected at the Redwing Site are
chlorinated hydrocarbons such as aldrin and carbamate compounds
such as butylate.  These compounds are not easily water soluble;
however, they are persistent and tend to remain in groundwater
and soil once transport has taken place.

Inorganic chemicals are widespread naturally in the environment
and occur in varying concentrations.  Inorganic chemicals in
aqueous form tend to be transported easily into groundwater and
surface water.  Several inorganic chemicals were detected in the
groundwater at the Redwing Site.

The groundwater at the Redwing Site has been impacted by
contaminants coming from the source material.  The highest
concentrations of contaminants in the groundwater occur in the
eastern half of the apartment complex but the surficial
groundwater has been impacted under almost the entire site.

The storm water from the Redwing Site contacts surface soils and
sludge seeps.  The contaminated sediments in the unlined northern
ditch are also a current vehicle for transport of chemicals of
concern.
                                27

-------
5.6
SOURCE AREAS OF CONTAMINATION
The results of the remedial investigation identified eight areas
of the Redwing Site as the source of the groundwater
contamination.  Those areas are shown on Figures 7 and 8.  The
bulk of the sludge was detected in the eastern area of the
Redwing Site.  This coincides with the area of highest
concentrations of groundwater contamination.  The source material
(i.e. sludge commingled with soil) was also concentrated in the
central area of the Redwing Site, the northwest area near
building 1200 and in two areas near the southwest corner of the
Redwing Site.

Table 6 shows the estimated volumes of source material which were
evaluated from the data collected during the RI.
TABLE 6 • AREAS AND VOLUME ESTIMATES FOR SOURCE
MATERIAL (INCLUDES SLUDGE) *
SOURCE
AREA
E-l
E-2 1
E-3 I
C-l 1
C-2 1
N-l I
SW-1 I
SW-2 |
TOTALS]
SQUARE
FEET
5,800
1,500
4,760
9,180
730
3,240
640
680
26,610
SLUDGE
THICKNESS
(FT)
2.0
0.5
2.4
1.2 '
2.5
1.5
2.0
1.0
n/a
SLUDGE
VOLUME
(CU. YDS)
433
29
423
408
68
180
47
25
1,613
SOURCE
MATERIAL
THICKNESS
(FT)
5
5
6
6
6
3.5
5
5
n/a
SOURCE
MATERIAL
VOLUME
(CU. YDS)
1,080
285
1,060
2,040
162
420
119
126
5,292
  * Source material includes black sludge and influenced soils,
6.0
SUMMARY OF SITE RISKS
CERCLA directs that the EPA protect human health and the
environment from current and future exposu.e to hazardous
                                28

-------
                                       FIGURE - 7
K)
10

-------
                                              FIGURE - 8
I  I— f^t-k ll-\     II OanalM prob«bl. »r««l
LEGEND     (   ) -i-Bl °r i«-•'•»••
               v	x ••t«rl«l.
                                             SB-I
                                                e F..I
Soil
                SA 4   I9BS II S EPA bnr Ing
                                       T.r-
                                          Soil    5 F..I tj.lo.
       FIGURE-8    Aeriol  extent
depths,   csnd thicl-cness  of
the  tor-~llke  moterlol.

-------
BLANK PAGE
 31

-------
 substances at Superfund sites.   In order to assess the current
 and future risks for th -  "edwing Site,  a baseline risk assessment
 (BRA)  was  conducted as :  _t of  the Remedial Investigation.   The
 BRA consists  of a human  ialth  and environmental  assessment  of
 current  and potential exposures at the  Redwing Site.

 As  defined by the 1990  National Oil  and Hazardous Substances
 Pollution  Contingency Plan (NCP),  the BRA:

   "characterize [s]  the current  and potential threats  to human
  health and  the environment that may be posed by contaminants
  migrating to ground water or  surface  water,  releasing to air,
   leaching through soil,  remaining in the soil, and
  bioaccumulating in the food chain."

 40  C.F.R 300.430(d)'->.  The BRA is organized into two major
 components, the Huir   Health Risk Assessment and  the
 Environmental Evalu  . ;>n.   The  risk assessment processes are
 evaluated  within ea   component.


 6.1    CONTAMINANTS OF CONCERN

 Tables 7A  and 7B provide a comprehensive list of  the  contaminants
 identified as chemicals of potential  concern (COCs) at the site
 in  their various media.  Chemicals provided in Tables 8A and 8B
 are the  contaminants which the  baseline risk assessment (BRA)
 indicated  might pose a current  or future significant  risk.   The
 criteria for  a significant risk was a carcinogenic risk level
 within or  above the acceptable  risk range (i.e.,  10E-4 to 10E-6),
 or  a hazard quotient greater than unity (1).   Tables  8A and  B
 also provide  the reasonable maximum exposure (RME)  concentrations
 which  were used in the BRA.

 The exposure  point concentrations are based on the 95% upper
 confidence limit (UCL)  of the arithmetic average.   The soil  UCLs
 are based  on  samples taken from the top 1 foot (12 inches) of
 soils  or sediments.
 6.2     EXPOSURE ASSESSMENT

 The  exposure assessment is the identification  of populations  that
 may  be exposed to the constituent  and the determination of the
 potential magnitude and duration of  their exposures.   A
 quantitative exposure assessment is  the  estimation of  the
 magnitude,  duration and frequency  of exposure  to various
•environmental media including both current and potential future
 exposures.
                                32

-------
                              TABLE - 7A
    CHEMICALS OF POTENTIAL CONCERN FOR SOILS. DITCH SEDIMENTS
                         AND TAR-LIKE MATERIAL
1.1,1-TRICHLOROETHANE
1,2,4-TRICHLOROBENZENE
1.4-DICHLOROBENZENE
2,4-D
2,4,5-T
2-BUTANONE (MEK)
4,4'-DDD
4,4'-DDE
4.4--DDT
4-METHYL-2-PENTANONE
4-METHYLPHENOL
ACENAPHTHENE
ACETONE
ALDRIN
ALPHA-BHC
ALPHA-CHLOROANE
ANTHRACENE
BENZALOEHYDE
BENZENE
BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZO(B)FLUORANTHENE
BENZO(G.H,I)PERYLENE
BENZO(K)FLUORANTHENE
BETA-BHC
BIS(2-ETHYLHEXYL)PHTHALATE
BUTYLATE
CADMIUM
CARBON OISULFIDE
CARBON TETRACHLORIDE
CHLOROBENZENE
CHLOROFORM
CHLORPYRIFOS
CHROMIUM (III/VI)
CHRYSENE
CYANIDE
DI-N-BUTYLPHTHALATE
DI-N-OCTYL PHTHALATE
DIBENZ(A,H)ANTHRACENE
DICAMBA
DIELDRIN
DIETHYLPHTHALATE
ENDOSULFAN I
ENDRIN
EPTC
ETHYLBENZENE
FLUORANTHENE
FLUORENE
GAMMA-BHC (UNDANE)
GAMMA-CHLORDANE
HEPTACHLOR ,
HEPTACHLOR EPOXIDE
INDENO(1,2.3-CD)PYRENE
LEAD
MANGANESE
MERCURY
METHOXYCHLOR
METHYLENE CHLORIDE
MOUNATE
NAPHTHALENE
PEBULATE
PHENOL
PYRENE
SELENIUM
TETRACHLOROETHENE
TOLUENE
VERNOLATE
XYLENE
ZINC
                                    33

-------
                 TABLE• 7B
CHEMICALS OF POTENTIAL CONCERN IN GROUNDWATPR
Chemical
2.4-0
2,4-Dimethylphenol
2.4,5-T
2-Butanone
4.4'-DDT
4-MethyJ-2-Pentanone
4-Methylpheno<
Acetone
Aldrin
Alpha-BHC
Arsenic
Barium
Benzoic Acid
Beryllium
Bis(2-ethylhexyl)pntnalate
Butylate
Caprofactum
Carbon Disulfide
Chloroform
Chromium (III/VI)
Copper
Cyanide
Di-n-butylphthalate
Di-n-octylphthalate
Dieldrin
Endrin
EPTC
Gamma-BHC
Heptacrdor
Iron
Lead
Manganese
Detected in Alluvial Aquifer




*


*


*
*

*
•
*
•


*
•
•

*


•

s
•
*
•
Detected in Surficial Water
Table Unit
•
•
•
*
•
•
*
•
•
*
*
»
*
•
*
•

•
•
*
*
*
*

*
*
•
•
*
*
*
•

-------
                TABLE - 7B
CHEMICALS OF POTENTIAL CONCERN IN GRQUNDWATER
Chemical
Methylene Chloride
Molinate
Naphthalene
Nickel
Pebuiate
Phenol
Selenium
Toluene
Vanadium
Vernolate
Zinc
Detected in Alluvial Aquifer



•




•
*
•
Detected in Surficial Water
Table Unit
*
*
*
•
*
*
•
*
*
•
*
* Detected in corresponding medium
                     35

-------
TABLE 8A - SURFACE SOIL AND SEDIMENTS RME CONCENTRATIONS
CONTAMINANTS OF CONCERN
BENZO (A) PYRENE
BENZO (B) FLUORANTHENE
BENZO (A) ANTHRACENE
CARBON TETRACHLORIDE
CHRYSENE
CONCENTRATION
RANGE
(jig/kg)
73 - 3,200
230 - 7,400
67 - 7,200
110,000
93 - 3,800
RME
CONCENTRATIONS
•(Jig/kg)
671
3,170
2,880
25,600
2,660
      TABLE 8B - GROUNDWATER RME CONCENTRATIONS
CONTAMINANTS OF CONCERN
4,4' -DDT
ACETONE
ALDRIN
ALPHA -BHC
ARSENIC
£RYLLIUM
BIS ( 2 -ETHYLHEXYL ) PHTHALATE
. CARBON DISULFIDE
CHLOROFORM
CHROMIUM
LEAD
METHYLENE CHLORIDE
NICKEL
VANADIUM '
VERNOLATE
CONCENTRATION
RANGE (ug/1)
0.96
10,000 -
2,100,000
0.11 - 0.47
0.044 - 0.15
4,000 - 29,800
1.3 - 9.5
2 - 620
9 - 5,500
2,900 - 27,000
6.2 - 355
2.4 - 162
330 - 650
28.7 - 301
6.6 - 580
1.1 - 140
RME
CONCENTRATIONS
(Jig/kg)
0.223.
1,520
0.121
0.0595
15
5.18
206
1,220
7,740
156
69.1
204
151
272
35.5
                         36

-------
The exposure assessment was conducted in three steps:  (1)
identification of exposure pathways, (2) estimation of
environmental concentrations and  (3) selection of exposure
assumptions and estimation of human intake.  Included was an
evaluation of possible exposure doses to people currently living
at the Redwing Site and potential future exposure doses due to
groundwater.

Exposure pathways at the Redwing Site were defined in terms of
the following elements: (1) a source and mechanism of chemical
release into the environment, (2) an environmental transport
medium, (3) a point of potential human exposure and (4) an
exposure route (e.g., ingestion of drinking water).

The media considered for both present and potential future
exposure are: (1) gro.undwater (alluvial and surficial),  (2) soils
and seeps of sludge  (tar-like material), (3) air, and  (4) on-site
ditch sediments.

Chemical concentrations used in the exposure assessment were
based on sampling data collected during the remedial
investigation. The exposure dose was calculated using the 95%
upper confidence limit (UCL) of the arithmetic mean of the
concentration unless this was greater than the maximum
concentration detected, in which case the maximum observed value
was used.   Whenever possible, actual sampling data were used.
When sampling data was not available, environmental fate and
transport modeling was used to estimate concentrations based on
the .sampling data.  Calculated chemical concentrations for the
exposure assessment used all detected concentrations of a
chemical plus half the quantification limit for each sample in
which that chemical was not detected.  Only chemicals that were
detected in at least one sample from the Redwing Site were
included in these calculations.   These data are summarized in
Tables XI-1 through XI-8 of Appendix XI of the RI Report for all
COCs.  Table 8A & 8B of this section provide a summary of the
more significant contaminants and their respective RME
concentrations.

Based on sampling results and Site layout,  four areas of possible
current exposure were identified as (1) the eastern portion of
the Redwing Site  (Target Area E), (2) the western portion of the
Redwing Site not covered by apartment buildings or pavement
(Grassy Area), (3) the Northern Ditch and  (4) the apartments'
living quarters.   The Redwing Site was divided into these four
areas for fate and transport modeling and calculations of human
intake.  The receptors considered for the exposure assessment
included an adult, a 9-year-old child  (the average of a child
ages 6 through 12 years) and a 4-year-old child  (the average of a
child ages 6 months through 6 years).

When site-specific data were not available, the exposure

                                37

-------
assumptions used in the risk assessment were based on standard
methodology.  Tables  9 through  L;, which were originally
presented in the RI Report as T.  le 6-8 and Tables 6-10 through
6-13, identify assumptions used in the risk assessment are
provided in the following pages.  In the tables and as presented
in the RI Report, the contaminated sludge is referred to as "tar-
like material."

6.2.1   EXPOSURE PATHWAYS

Groundwater:  The surficial groundwater is a potential drinking
water source.  For the City of  Saraland, the alluvial aquifer is
a current and potential future  drinking water source.  Presently,
three municipal wells located within 1.5 miles of the Redwing
Site receive water from the alluvial aquifer.  Although no wells
are located on the Redwing Site,  there are several private wells
located within a one-mile radius  of the ." edwing S:te.  These
wells were installed  at various depths a;.d contact the surficial
as well as the alluvial aquifer.  Remedial Investigation sampling
data revealed contamination in  on-site groundwaters, however,  no
Site related contaminants were  detected in off-site wells.  The
potential future exposure associated with a well installed on the
Redwing Site was evaluated.  The  evaluation addressed potential
future exposure to groundwater  from both the surficial and
alluvial aquifer as a result of ingestion and showering.

Soils:  Exposure to soils and seeps at the Redwing Site may occur
through incidental ingestion, dermal contact or inhalation of
vapors and particulates.  Actual  exposure at the Redwing Site has
not been measured, therefore, conservative default estimates were
used.  Possible exposure to soils and seeps was estimated by
proportionally dividing exposure  (time of contact and ingestion
mass) among the three outdoor areas (Target Area E, Grassy Area
and Northern Ditch) and seeps for relative .i.ntribution of risk.
Seeps (Sludge):  The  ongoing removal of seeps by Redwing has not
been incorporated into the BRA.   The maximum seep area was
estimated using historical data in conjunction with ground-level
and aerial photographs from the period prior to the current seep
inspection and removal program.  Additional seep analyses were
conducted which estimates exposure of sludge (tar-like material)
seeps found at the Redwing Site.  Methodology assumptions used to
estimate the total seep area and  the resulting risk estimates are
presented in Appendix XVII of the BRA.

This analysis resulted in a total seep area of 540 ft2 or 0.34%
of the potential exposure area  (sum of Target Area E and Grassy
Area less the area of apartments  and Northern ditch).  The
population potentially exposed  to the seeps are residents of
Saraland Apartments consisting  of approximately 96 adults and 64
children.  The estimate of seep constituent concentrations
include all samples of sludge regardless of depth.


                                38

-------
            TABLE - 9
EXPOSURE ASSUMPTIONS FOR U/BK MODEL
Exposure Assumption
Air Data
Concentration (^g Pb/m3)
Lung Absorption
Breathing Rate (m'/d)
Diet Data
Intake (»g Pb/day)
Water Data
Jftmount Ingested (liters/day)
Soil/Dust Data
Percent of soil and dust that is soil
Amount ingested (mg/day)
Soil contribution to house dust
U/BK Default'
0.202
32.0%
4.5
6.38
0.48
45%
100
28%
Saraland Modification
NM
NM
8
NM
1.3
NM
200
NM
' Average for children ages 0 to 6 years old.
* Mean concentration in urban air (USEPA 1990b).
NM - Not modified.
               39

-------
          TABLE  10



SUMMARY OF USEPA ASSUMPTIONS
Exposure Assumptions
Ingestion of water
o Amount ingested per day
•adult
-9-year-old
-4-year-old
o Years exposed (adult)
Showering
o Breathing rate
o Years exposed (adult)
Soil and tar-like material ingestion
o Amount ingested
-Adult
- 9-year-old
- 4-year-old
o Days/year exposed
adult and children
Dermal contact with soil (all areas)
o Adherence factor
sofl
tar-like material
o Days/year exposed
adult and children
Dermal Absorption
o Organics
o Inorganics
Vapor Inhalation indoors
o Days/year exposed indoors
adult and children
RAGS
(USEPA
1989b)/1991a)
2 liters
30 years
30 years
100 mg/day
100 mg/day
200 mg/day
350 d/year
350 d/year

350 d/year
Exposure Factors
Handbook
(USEPA 1989a)
1.5 liters
1.3 liters
0.6 m3/hr




New Interim Region
IV Guidance
(USEPA 1992)
I '


0.2 mg/cm2
1 .0 mg/cm2
1.0%
,_ 0.1%

              40

-------
            TABLE  11



SUMMARY OF NON-USEPA ASSUMPTIONS
Exposure Assumption
Showering
o Tim* exposed adult
o Years exposed (children)
Incidental ingestion of soil and
dermal contact (all areas)
o Years exposed-adult
Dermal contact with soil (all areas)
o Surface area
• adult
• 9-year old
- 4-year old
Inhalation of particulates
o Contact time
Inhalation of vapors
o Outdoor-contact time
o Indoor-contact time
RAGS
(USEPA 19895)
7(12) min per day average
(worst) case
NA
30years-
90th percent) le at one
residence

Dependent on duration of
exposure
Dependent on duration of
exposure
Dependent on duration of
exposure
Hypothetical
Values Used in
Saraland Risk
Assessment
36 min/day
6/5.5 years
9.6 years
2756cm2
3655cm*
2522cm2
8 hr/day
8 hr/day
16 hr/day
Rationale for Non-USEPA
Assumptions
Adjust .for additional indoor air
exposure (e.g.. dishwasher)
due to volatilization from water
Number of years for each age
group
95% UCL for residence at
Saraland Apartments. Children
exposed over total age period.
Assumed face and 2/3 upper
limbs for adult, and face,
2/3 upper limbs and 1/2 lower
limbs for children (ICRP 1984)
Assumed to be the reasonable
maximum exposure time
outdoors
Assumed to be the reasonable
maximum exposure time
outdoors
Assumed to be the reasonable
maximum exposure time
indoors

-------
          TABLE  12




GENERIC EXPOSURE ASSUMPTIONS1
Assumptions
Days per Lifetime
Years of Exposure4
Body Weight (kg)
Breathing Rate (m'/rir)
Total Body Surface Area (cm2)6
Surface Area of Lower Limbs (cm2) (37.5%)
Hands (cm2) (5.2%)
Upper Limbs (cm2) (18.8%)
Head and Neck (cm2) (7.8%)
Adult
25,550
9.6*
70
0.833
16,900
6." .17.5
£ .8
3,177.2
1.318.2
9-Year-2
Old Chad
25.550
69
31
0.6256
10,425
3.909.4
542.1
1,959.5
813.2
4-Year-3
Old Chad
25,550
5.5s
14.5
0.333'
7.195
2,698.1
374.1
1.352.7
561.2
Notes:
USEPA 1989a
3 Average of a child ages 6 to 12 years.
3 Average of a child ages 6 months to 6 years.
4 Upper 95th percentile value for residents currently residing at the Saraland Apartments. For
hypothetical groundwater exposure scenarios, 30 years (USEPA upper 95th percentile for
U.S. residence at a location) will be used.
9 Based on adult residence time of 9.6 years, child could theoretically reside at Saraland
Apartments for entire time period within this age group.
8 ICRP 1984.

-------
                        TABLE  13
SPECIFIC EXPOSURE SCENARIO ASSUMPTIONS FOR THE RME RECEPTOR
Exposure Scenario Assumptions
Adult
9-Year-
Old
Child
4-Year-
Old
Child
Reference
HYPOTHETICAL FUTURE EXPOSURE: Assumes future installation of water supply wells
INGESTION OF WATER. ALLUVIAL AQUIFER
Amount ingested (I/day)
Number of contacts total (days/yr * yrs exposed)1
INGESTION OF WATER. SURFICIAL WATER
TABLE UNIT (ON-SITE AND OFF-SITE)
Amount of water ingested (I/day)
Number of contacts total (days/yr * yrs exposed)1
SHOWERING, ALLUVIAL AQUIFER
Breathing Rate (m3/hr)
Time Exposed (hr/day)
Number of contacts total (days/yr*yrs exposed)1
SHOWERING, SURFICIAL WATER TABLE UNIT
(ON-SITE AND OFF-SITE)
Breathing Rate (m3/hr)
Time Exposed (hr/day)
Number of contacts total (days/yr • yrs exposed)1
2
10500
2
10500
0.6
0.6*
10500
0.6
0.6s
10500
1.5
2100
1.5
2100
0.6
0.43
2100
0.6
0.43
2100
1.3
1925
1.3
1925
0.6
0.43
1925
0.6
0.4'
1925
USEPA 19893
1989b
USEPA
19895/1991 a
USEPA 1989a
USEPA
19890/1 991 a
USEPA 1989b
ENVIRON
USEPA
1989a/1991 a
USEPA 19696
ENVIRON
USEPA
1989a/1 991 a
CURRENT EXPOSURE
INGESTION OF SOIL Eastern sector
Amount ingested (kg/day)
Total time of ingestion (days/yr * yrs exposed)
Days exposed per year
Fraction of time in Eastern sector
INGESTION OF SOIL, Western/Central sector
Amount ingested (kg/day)
Total time of ingestion (days/yr * yrs exposed)
Fraction of time In Western/Central sector
INGESTION OF TAR -LIKE MATERIAL
Amount ingested (kg/day)
Ingestion time (days/yr ' yrs exposed)
Fraction of time exposed to seeps of tar-like
material
0.0001
3360
350
49.83%
0-0001
3360
49.83%
0.0001
3360
0.34%
0.0001
2100
350
72.83%
0.0001
2100
18.83%
0.0001
2100
0.34%
0.0002
1925
350
55.83%
0.0002
1925
38.83%
0.0002
1925
0.34%
USEPA 1989b
USEPA 1991 a/
ENVIRON
USEPA 19913
ENVIRON
USEPA 1989b
USEPA 1991 a/
ENVIRON
ENVIRON
USEPA 1989b
USEPA 19913/
ENVIRON
ENVIRON

-------
                         TABLE  13



SPECIFIC EXPOSURE SCENARIO ASSUMPTIONS FOR THE RME RECEPTQR


Exposure Scenario Assumptions
INGESTION OF SEDIMENTS. NORTHERN DITCH
Amount Ingested (kg/day)
Total time of ingestion (days/yr • yrs exposed)

Fraction of time in ditch
DERMAL, SOIL, Eastern sector
Number contacts total (days/yr * yrs exposed)

Days expcted per yea'
Son to skin adher= :e factor (K^'cm2)
Dermal absorptio- 4)
Compounc Class Specific
organics
inorganics
Surface area of contact (cm2)
for Adult = Face + 2/3 Upper limbs
for NINE and FOUR = Face + 2/3 Upper
limbs + 1/2 Lower limbs
Fraction of time in Eastern sector
DERMAL, SOIL, Western/Central sector
Number contacts total (days/yr * yrs exposed)

Son to skin adherence factor (kg/cm2)
Dermal absorption (%)
Compound Class Specific (see above)
Surface area of contact (cm*)
Fraction of time in Western/Central sector
DERMAL, TAR-UKE MATERIAL
Number contacts total (days/yr * yrs exposed)

Soil to skin adherence factor (kg/cm2)
Dermal absorption (%)
Compound Class Specific (see above)
Surface area of contact (cm2)

Fraction of time exposed to seeps of taNike
material


Adult

0.0001
3360

0%

3360

350
2.00E-07


1%
0.1%
2756



49.83%

3360

2.00E-07


9-Year-
Old
Child

o.oooi
2100

8%

2100

350
2.00E-07


1%
0.1%
3655



72.83%

2100

2.00E-07


2756 3655
49.83%

3360

1.00E-06


2756

0.34%

18.83%

2100

1.00E-06


3655

0.34%

4-Year-
Old
Child

0.0002
1925

5%

1925

350
2.00E-07


1%
0.1%
2522



55.83%

1925

2.00E-07


2522
38.83%

1925

1.00E-06


2522

0.34%



Reference

USEPA 1989b
USEPA 1991 a/
ENVIRON
ENVIRON

USEPA 19913/
ENVIRON
USEPA 19913
USEPA 1992


USEPA 1992
USEPA 1992

USEPA 1989a
ENVIRON

ENVIRON

USEPA 1991 a/
ENVIRON
USEPA 1992

USEPA 1992
USEPA 1989a
ENVIRON

USEPA 1991 a/
ENVIRON
USEPA 1992

USEPA 1992
ICRP 1984/
ENVIRON
ENVIRON


-------
                        TABLE  13
SPECIFIC EXPOSURE SCENARIO ASSUMPTIONS FOR THE RME RECEPTOR
Exposure Scenario Assumptions
DERMAL SEDIMENT, NORTHERN DITCH
Number contacts total (days/yr * yrs exposed)
Soil to skin adherence factor (kg/cm2)
Dermal absorption (%)
Compound Class Specific (see above)
Surface area of contact (cm2)
Fraction of time in ditch
INHALATION - PARTICULATES, Eastern sector
Contact time (hr/day)
Number contacts total (days/yr ' yrs exposed)
Fraction of time in Eastern sector
INHALATION - VAPORS. Eastern sector
Contact time (hr/day)
Number contacts total (days/yr • yrs exposed)
Fraction of time in Eastern sector
INHALATION - VAPORS, Western/Centra) sector
Contact time (hr/day)
Number contacts total (days/yr * yrs exposed)
Fraction of time in Western/Central sector
INHALATION - VAPORS, TAR-LJKE MATERIAL
Contact time (hr/day)
Number contacts total (day/yr * yrs exposed)
Fraction of time exposed to seeps of tar-like
material
INHALATION - VAPORS. INDOORS
Contact time (hr/day)
Number contacts total (days/yr * yrs exposed)
Fraction of time indoors
Adult
3360
2.00E-07
2756
0%
2
3360
49.83%
2
3360
49.83%
2
3360
49.83%
2
3360
0.34%
22
3360
100%
9-Year-
Old
Child
2100
2.00E-07
3655
8%
2
2100
72.83%
2
2100
72.83%
2
2100
18.83%
2
2100
0.34%
22
2100
100%
4-Year-
Old
Child
1925
2.00E-07
2522
5%
2
1925
55.83%
2
1925
55.83%
2
1925
38.83%
2
1925
0.34%
22
1925
100%
Reference
USEPA 1991 a/
ENVIRON
USEPA 1992
USEPA 1992
ENVIRON
ENVIRON
ENVIRON
USEPA 1991 a/
ENVIRON
ENVIRON
ENVIRON
USEPA 1991 a/
ENVIRON
ENVIRON
ENVIRON
USEPA 1991 a/
ENVIRON
ENVIRON
ENVIRON
USEPA 1991 a/
ENVIRON
ENVIRON
ENVIRON
USEPA 1991 a/
ENVIRON
ENVIRON
1 Based on default USEPA value for length of residence, 350 days per yean 30 years (adult). 6
years (9 year old) and 5.5 years (4 year old).
2 Based on Inhalation during 15 minute daily shower and additional exposure to other voiatues for
20 minutes per day.
3 Based on inhalation during 24 minute bath.
                           45

-------
Air:  Although exposures have not been measured, exposure to
constituents through inhalation of vapor and particulates
ispossible.  Possible exposures to vapors in the grassy area,
indoors, target area E and the sludge have been evaluated via
mathematical modeling.  Indoor exposure may occur from the
inhalation of vapor that may diffuse through concrete foundation
cracks or utility openings.  In addition, outdoor ambient air
concentrations can contribute to indoor air concentrations.
Total indoor air concentrations were estimated from the sum of
modeled indoor and outdoor ambient air concentrations.


6.3     TOXICITY ASSESSMENT:  DOSE  RESPONSE  EVALUATION

The toxicity assessment evaluates the adverse effects on humans
due to exposure to the chemicals of concern.  The dose-response
evaluation is the characterization of the  relationship between
the dose received and the resulting effect.  The toxicity values
are then derived from quantitative dose-response relationships.
These values are used to predict the incidence or probabili-y of
an adverse effect occurring relative to a dose.  Toxicity values
are used during risk characterization to estimate the possibility
of an adverse effect occurring under a given set of
circumstances.

Scientists have developed several mathematical models to
extrapolate low-dose carcinogenic risks to humans based on
carcinogenicity observed at high doses typically used in
experimental animal studies.  These models provide an estimate of
the upper limit on lifetime cancer risk per unit dose,
Carcinogenic Slope Factor (CSF).  The mathematical model used by
EPA to generate CSFs is a linearized multistage model.

Non-carcinogenic risks for long-term exposures are characterized
by the chronic reference dose  (RfD) for ingestion,  or reference
concentration (RfC) for inhalation which is similar in concept to
an "acceptable daily intake."  The RfD or RfC represents an
estimate of daily exposure that is not expected to result in an
increased risk of adverse health effects.  Initially, the
threshold dose is identified by determining the
no-observed-effect level  (NOEL), or, if a NOEL is not available,
the lowest-observed-effect level  (LOEL) from observations of
people or experimental animals.

Toxicity values developed by EPA  (RfDs, RfCs, and CSFs) have been
used to characterize risk for all compounds except Lead and PAHs.
Lead and PAHs are discussed below.  Table 14, summarizes utilized
toxicity values from Appendix XII of the RI report.

For polynuclear aromatic hydrocarbons  (PAHs), a CSF has been
onlyestablished for benzo(a)pyrene  (BaP).  Therefore, a Region IV
interim guidance document has recently adopted a toxicity

                                46

-------
TABLE - 14
REFERENCE DOSES. REFERENCE CONCENTRATIONS AND CANCER SLOPE FACTORS

CHEMICAL
Acenaphthene
Acetone
AJdrln
Anthracene
Benz(a)anlhracene*
Bens(a)pyrene
Benialdehyde
Benzene
Benio(b)fluorenlhene'
Bemo(ghl)perylene
Benzo(k)fliiorantlMfw*
BeniotoAcW
Bls(2-elhy(hexyt)phthalate (BEHP)
Bulylete
Caprolactam
Carbon dlsulflda
Carbon tetrechlorlde • Tetfachroromethane
NON-CARCINOCENIC
lekeLWC
Imifln/tor)
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
2.86 x 10 '
NA
InhaL RIC
SOURCE















HEAST 1991

Oral RID
(mc/M/tfar)
6.00x10*
1.00 X 10 '
3.00 X 10 9
300 X 10 '
NA
NA
1.00x10*
NA
NA
300x10*
NA
4.00
2.00 x 10*
5.00 x 10*
5.00 x 10 '
1.00 x 10 '
7.00 x 10"*
Oral RID
SOURCE
HEAST/inS 1991
HEAST/inS 1991
HEAST/IRIS 1991
HEAST/IRIS 1991


HEAST 1991


HEAST/IRIS 1991

HEAST 1991
HEAST/IRIS 1991
HEAST/IRIS 1991
HEAST 1991
HEAST/IRIS 1991
HEAST/IRIS 1991
CARCINOGENIC
InkiL CSF
l/(mj/lt/day)
NA
NA
1.70 x 10*
NA
6.10x10*
6.10
NA
2.90 x 10 *
6.10x10*
NA
6.10x10*
NA
NA
NA
NA
NA
1.30 x 10 *
InhiL CSF
SOURCE


HEAST/IRIS 1991

HEAST 1991
(BaP TEF)
HEAST 1991

HEAST/IRIS 1991
HEAST 1991
(BaP TEF)

HEAST 1991
(BaP TEF)





HEAST/IRIS 1991
Oral CSF
l/d-tAt/**)
NA
NA
1.70 x 10*
NA
5.80x10*
5.80
NA
2.90 x 10*
5.80x10*
NA
5.80x10*
NA
1.40 x 10*
NA
NA
NA
1.30x10'
Oral CSF
SOURCE


HEAST/IRIS 1991

HEAST 1991 (BaP
TEF)
HEAST 1991

HEAST/IRIS 199t
HEAST 1991
(BaP TEF)

HEAST 1991
(BaP TEF)

HEAST/IRIS 1991



HEAST/IRIS 1991

-------
TABLE -14
REFERENCE DOSES. REFERENCE CONCENTRATIONS AND CANCER SLOPE FACTORS

CHEMICAL
Chlordana (alpha)
Chlordan* (gamma)
ChtorolMnzviM • MooocJitorobanMo*
Chloroform • TrteMoromattwiw
Chlorpyrlfot
CfiiyMn*'
Crawl (p-) (4-Mattiyl Phanol)
2.4-0 (2.4 OcMoroptwnoxyacctio acid)
Ol-n-btilyl pttihalai*
Oi-fl«dyl phthalat*
Dib«ni(a,h)anttiracan«l
DteamtM
»!-•_• t- M. * >
p-OeMorobantafl*
DfchlprodlprMflyl dteMonMttuM (p.p1-)
(ODD)
DtcMofodlphanyl dtehtonMttiyton* (p-pl
(DOE)
NONr>
1.30
1.30
NA
8.10x10*
NA
6.10x10*
NA
NA
NA
NA
6.10
NA
NA
NA
NA
IrtaL CSF
SOURCE
HEAST/IWS 1991
HEAST/IRIS 1991

HEAST/IRIS 1991

HEAST 1991
(BaPTEF)




HEAST 1991
(OaPTEF)




OnlCSF
i/(m/i«/-'-.>
1.30
1.30
NA
6. 10 x Iff4
NA
5.80x10*
NA
NA
NA
NA
6.60
NA
2.40x10*
2.40 xlO'1
3.40 x 10 '
OnlC5F
SOURCE
HEAST/IRIS 19!
HEAST/lfVS 10

HEAST/IRIS 19S

HEAST 1991
(BaPTEF)




HEAST 1991
(BaPTEF)

HEAST 1991
HEAST/IWS 1991
HEAST/IRIS 1891
   /.a

-------
TABLE -14
REFERENCE DOSES. REFERENCE CONCENTRATIONS AND CANCER SLOPE FACTORS

CHEMICAL
Dichkxodlphanyftrlchloroethan* (p.p1-)
(DDT)
DiolhyiphthalalB
Oleldrln
Dimalhylphanol (2.4-)
Endosulfan
Endosulfan IIs
Endrln and meiaboliwi
Ethyl 
-------
              CHEMICAL
 Mwx>(1.2.3)pyr«n«'
 Mithoxychtof
 Mtltiyt •%< MI-M ;f,n K) - 2-txitanon*
 Mrthyt Itobutyi fc
Pfwnol
2.4.5-T
Tolu«n* • Toluol
Ttlctik)fOb«nw» (1,2.4-)
TflchkKO«tti«n» (1.1,1-)
Vtmolit*
Xyten*a
                                                                        TABLE -14
     NA

     NA
  9.00 x 10 *
 8.60 x JO'
    NA
    NA
    NA
    NA^
    NA
    NA
  _NA_
8.71 x 10'
                                       NA
                                    8.60 x 10 *
                    )NCENTRAT»ON!
      NON^CARCINOCENIC
hluLRIC  I   OralRfD   I     OralRfD
                             SOURCE
               0.00
                                                      SOURCE
                                                    HEAST 1991
                                                    HEAST 1991
                                                    HEAST 1991
            HEAST 1991
            HEAST 1991
            HEAST 1991

            HEAST 1991
             g.OO »
             5.00 K 1Q»
             5.00 n 10'*
            6.00 n
            2.00
            4.00 K
            5.00x10^
            6.00 ii 10 '
          ^3.00 x 10*
            1.00 K 10a
          j.oomo-a
          _2.00 ic 10 *
           t.31
          1.00K103
             2.00
  HEAST/IRIS 1991
    HEAST
    HEAST 1991
  HEAST/IRIS 1991
  HEAST/IRIS 1991^
    HEAST 1991
        '1991
 HEAST/IRIS 1991
 HEAST/IHIS 1991
 HEAST/intS 1991
 HEAST/IRIS 1991
  HEAST 1991
  HEAST 1991
  HEAST 1991
HEAST/IRIS 1991
                                                                                                  lnh.1 CSP
6.10x10'

   NA
   NA
   NA
1.65 XJIO3
  _NA_
   NA
   NA_
  NA
 _NA_
  NA
                                                                                                                  InkiL CSP
                                                                                                                   SOURCE
                                                                                                                 HEAST 1991
                                                                                                                 JBaP TEF)
                                                                                     CARCINOGENIC
                                                                                              Oral CSP
                                                                                                                 HEAST 1991
                                                                                                               HEAST 1991
 5.80 x 10'

   _NA_
    NA
   _NA_
 7.50 xIQ"3
   _NA
   NA
  _NA_
   NA^
  _NA_
  _NA_
'.10x10*
 _NA_
 _NA_
 _NA_
 _NA_
 NA
                                                                           r>0

-------
                         TABLE -14
REFERENCE DOSES. REFERENCE CONCENTRATIONS AND CANCER SLOPE FACTORS

CHEMICAL
Arsenic
Barium
Beryllium
Cadmium dusts & tails (•• Cd)
Chromium (III)
Chromium (VI)
Copper
Cyanides (•• CM)
Manganese
Mercury • Inorganic
Ntefcel
Selenium
Vanadium
Zino and oompoundi
NON-CARCINOCENIC
lakaLMC
(«c/ks/
NA
NA
NA
NA
5.70 X 10 r
5.70 x 10'7
NA
NA
1.14 x 10"*
8.57 x 10 9
NA
NA
NA
NA
InhiL RfC
SOURCE




HEAST 1991
HEAST 1901


IRIS 1991
HEAST 1991




Oral RID
(rac/kc/da;)
3.00 x 10~*
7.00 x 10'*
.5.00x10'
5.00 x 10"*
1.00
5.00 x Iff3
1.00
2.00 x 10*
1.00 x 10 '
3.00 xHT4
2.00 x 10*
5.00 x 10^
7.00 x 10"3
2.00 x 10 '
Oral RID
SOURCE
IRIS 1991
IRIS 1991
IRIS 1991
HEAST/IRIS 1991
HEAST 1991
IRIS 1991
IRIS 1991
HEAST 1991
IRIS 1991
HEAST 1991
HEAST 1991
IRIS 1991 .
HEAST 1991
HEAST 1991
CARCINOGENIC
InNaL CSF
l/(iH8/kg/d.r)
5.00 x 10*
NA
8.40
6.30
NA
4.20 x 10*
NA
NA
NA
NA
8.40 x 10 '
NA
NA
NA
Inhal CSF
SOURCE
HEAST 1991

IRIS 1991
IRIS 1991

IRIS 1991




HEAST 1991



Oral CSF
l/(mt/ftt/«iay>
1.75
NA
4.30
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Oral CSF
SOURCE
IRIS 1991

IRIS 1991





*





1 Cancer elope factou have been adjusted using toxlclty equivalency factor (TEF) methodology as cited In New Interim Region IVGuidanct. February 1992 memo from USEPA Region IV.
2 HEAST 1991 and IRIS 1991 provide references for Endosulfan only. These values were also used for Endosuffan II.

-------
equivalency factor  (TEF) methodology  for carcinogenic PAHs based
on the relative potency of each compound to the potency of BaP.
The oral CSF for BaP  is 5.8  (mg/kg-day)"'.  Therefore, compounds
with a TEF of 0.1 were evaluated using oral CSFs of 0.58  (mg/kg-
day)'1.  This TEF approach was  used for inhalation, dermal and
oral exposure pathways  (see  Table  15).


TABLE 15 -  TOXICITY EQUIVALENCY FACTORS  (TEFs)  FOR POLYNUCLEAR
            AROMATIC HYDROCARBONS (PAHs)

  Compound                         TEF

  Benzo(a)anthracene               0.1
  Benzo(b)fluoranthene             0.1
  Benzo(k)fluoranthene             0.1
  Chrysene                         0.01
  Dibenzo(a,h)anthracene           1.0
  Indeno(l,2,3-c,d)pyrene          0.1


For Lead, the RfD or  CSF currently does not exist, nor are value's
likely to be developed in the  foreseeable future due to
difficulty of detecting effects of very low levels of lead
exposure.  The Uptake/Biokinetic  (U/BK) model, developed by
Harley and Kneip (USEPA 1991b), has been used by the USEPA Office
of Air Quality Planning and  Standards to set the National Ambient
Air Quality Standards (NAAQS)  for  lead.  Also, the Environmental
Criteria and Assessment Office (ECOA) has distributed the U/BK
model as a method for establishing soil cleanup levels for lead.
Accordingly, the U/BK model  was used  in the Risk Assessment for
this site as the most appropriate  method currently available to
estimate the potential risks associated with exposure to lead.


6.4     RISK  -lARAv-TERIZATION

Human health risks  are characterized  for potential carcinogenic
and noncarcinogenic effects  by combining exposure and toxicity
information. Excessive lifetime cancer risks are determined by
multiplying the estimated daily intake level with the cancer
potency factor.  These risks are probabilities that are generally
expressed in scientific notation  (e.g., 1'x 10"6) .  An excess
lifetime cancer risk  of IxlO'6  indicates that,  as a plausible
upper bound, an individual has a one  in one million additional
(above their "normal risk) chance of developing cancer as a result
of site-related exposure to  a  carcinogen over a 70-year lifetime
under the assumed specific exposure conditions at a site.

The Agency considers  individual excess cancer risks in the range
of IxlO"4  to IxlO'6  as protective;  however the  IxlO'6 risk level is
generally used as the point  of departure for setting cleanup

                                52

-------
levels at Superfund sites.  The point of departure risk level of
IxlO"6 expresses EPA's preference for remedial actions  that
result in risks at the more protective end of the risk range.

Potential concern for noncarcinogenic effects of a single
contaminant in a single medium is expressed as the hazard
quotient  (HQ)  (or the ratio of the estimated intake derived from
the contaminant concentration in a given medium to the
contaminants's reference dose).  A HQ which exceeds one (1)
indicates that the daily intake from a scenario exceeds the
chemical's reference dose.  By adding the HQs for all
contaminants within a medium or across all media to which a given
population may reasonably be exposed, the Hazard Index (HI) can
be generated.  The HI provides a useful reference point for
gauging the potential significance of multiple contaminant
exposures within a single medium or across media.  An HI which
exceeds unity indicates there may be a concern for potential
health effects resulting from the cumulative exposure to multiple
contaminants within a single medium or across media.  Tables 16
and 17 provide a summary of specific carcinogenic and
noncarcinogenic risks respectively.  The future potential
exposure to the surficial and/or alluvial aquifer were the only
pathways which represent an unacceptable risk.


6.5  UNCERTAINTY ANALYSIS

Throughout the risk assessment process, uncertainties associated
with evaluation of chemical toxicity and potential exposures
arise.  For example, uncertainties arise in derivation of
toxicity values for reference doses  (RfDs) and carcinogenic slope
factors   (CSFs), estimation of exposure point concentrations,
fate and transport modeling, exposure assumptions and ecological
toxicity data.  Because of the conservative nature of the risk
assessment process, risks estimated in this assessment are likely
to be overestimates of the true risk associated with potential
exposure at the Redwing Site.

Because of the uncertainty in the calculation of the total area
occupied by seeps, three different estimations of seep area were
conducted in the risk assessment.  This was done to quantify the
range of possible exposure and the resulting risks at the Redwing
Site.  These calculations are presented in the RME scenario
(Section 6.2.3.4) of the RI Report and in Appendix XVII of the
Report.

Since 1985, a seep inspection and removal program has been
implemented at the Redwing Site.  As a result, seeps have not
been observed to increase in size beyond approximately 2 inches
in diameter.  However, the risk assessment was conducted to
evaluate risks associated under the conditions that would occur
at the Redwing Site if the removal actions were not occurring.

                                53

-------
TABLE 16 - SUMMARY OP PATHWAY SPECIFIC CARCINOGENIC
RISKS
E 705'JRE SCENARIO
ALLUVIAL ACVIFSR
ingest ion of water
inhalation during showering
SUHFICIAL AQUIFER
ingest ion of water
inhaiation during showering
ADULT
CANCER
RISK
9 YEAR OLD
CANCER RISK
4 YEAR OLD
CANCER RISK
SUM OF 9 AND
4 YEAR OLD
CANCER RISK

5xl
-------
TABLE 17 - SUMMARY OF PATHWAY SPECIFIC TOTAL HAZARD
INDICES (NON-CARCINOGENIC RISKS)
EXPOSURE SCENARIO
ADULT
ALLUVIAL AQUIFER.
Ingest ion of water
Inhalation during showering

SUr.FICIAL AC'-IFER
i~3-~stion of water
Inhalation during showering
2xioc
0
NINE-YEAR-
OLD
FOUR-YEAH-
OLD

4X10°
0

3X101
8X10°
5X101
ix:o:
ex:?°
0

9X101
3x:c:
TARGET AREA E
ir.gesticn of soil
dermal contact Iw/soil)
inhalation (vapors)
inhalation (particulates)
4X1C"
2X10-'
ixio-'
3X10"
ixio"
8X10'J
2x:o-J
8X10'2
5X10-1
9X10"
2X10-)
7X10"
GRASSY AREA
ingestion of soil
dermal contact (w/soil)
inhalation (vapor)
3X10°
9X10-1
2X10'4
2X10'J
ixio-4
1X10"
2X10"
3X10-4
2x:o-4
INDOOR EXPOSURE
inhalation of vapor (includes seeps!
inhalation of vapor (excludes seepsl
3X10"
5X10"
5X10-'
8X1C-'
SX10"
9X10-'
NORTHERN DITCK
ingestion of sediments
dermal contact with sediments
EXPOSURE TO SEEPS OF SLUDGE.
ingestion of sludge
dermal contact with sludge
inhalation of vapors
TOTAL CURRENT BXPOSTOB
[Includes risks from eastern+western/ central*
indccr-ditch»seeps . ]
TOTAL POTBHTXAL KXPOSOTB
Includes currents exposure + exposure co the
alluvial aquifer.
Includes current exposure » exposure to the
surficial groundwater.
0
0

ixicr4
2X10'5
2X10"'
1X10''

3X10°
4X101
7X10-'
3X10-'

3X10"
6X10'5
4X10"
SxlO'1

5X10"
6X1 01
2x:c-J
3X10'4

1X10"
9X10-5
4X10"
7x10"

9X10°
1X10'
55

-------
.-"! alte.   .tive se=p a.-alysis  -'as conducted assuming a maximum
i.;ssibl.   eep area of  10,400  _c2.  This is 20 times greater than
tne arei used in the RME scenario.  Using the alternative seep
analysis, Els for the  9 and 4-year-old children exceed 1.  The
alternative seep area  also increased carcinogenic risks under the
current exposure scenario by  an order of magnitude.


6.6  HUMAN HEALTH SUMMARY

EPA evaluated present  and possible future exposure from 1)
surficial and alluvial groundwater, 2) soils and seeps of sludge,
3) air and (4) site surface water and sediments.  The risk
assessment indicates that contaminant levels in surface soil,
sediments and sludge seeps are not high enough to pose a
significant health threat via current exposure.  Furthermore,
there is no current exposure  to people from  voundwater or
subsurface soil contamination.  However, CO'   :ould pose a future
health risk if the surficial  aquifer were u:   as a source of
potable water or if contamination moves int    \e alluvial
aquifer.   Additionally, COCs  may pose a hea.   risk if the PAHs
detected under the concrete liner become ex   sd because of the
removal of the liner,  or if similar contami..... _ion is found
elsewhere along the drainage  pathway.  The COCs in the northern
ditch do not currently present a significant human health threat.


6.7    ENVIRONMENTAL EVALUATION

The environmental evaluation  examined the potential for adverse
ecological impacts as  a result of the presence of the chemicals
at the Redwing Site.   The evaluation was conducted in four steps:
(1) identification of  the presence of critical habitats _and
species of concern,  (2) identification of chemicals of potential
concern,   (3) estimation of a.:ute and chronic toxicity and
exposure concentrations, and  >4) comparison of toxicity threshold
estimates and exposure estimates.

The ecological risk assessment primarily addressed risk to on-
site receptors.  The Redwing  Site is mostly a non-vegetated, non-
aquatic habitat in an  urban/residential area and does not provide
any special or unique  habitats.  Therefore, it is unlikely to
attract or support endangered or threatened species.  Terrestrial
(land) plants are limited to  mowed grass and a few bushes and
trees.  Animals likely to be  found at the Redwing Site are song
or field birds, small  rodents, frogs, and possibly reptiles.
Although Redwing Site  contaminants might have harmful effects on
some plants and animals, the  source area is presently covered
with soil making direct exposure unlikely.  Wildlife would
probably avoid the tar seeps.  Therefore, the source material
does not a. pear to pose an environmental risk.


                                56

-------
Site ditches provide only temporary habitats for aquatic plants
and animals.  Two aquatic species, the arrowhead plant and the
mosquitofish, were observed in the concrete-lined ditches
following heavy rainfall.  The mosquitofish would likely move
downstream as water in the ditch dries up.  Since contaminants in
unlined ditch sediments could move downstream and those in the
lined ditch could have moved in the past,  data from on-site ditch
sediments were used to predict effects on plant and animal life
in downstream surface water bodies.  The analysis indicated that
the highest contaminant concentrations were found under the
concrete liner in the ditch and measurable levels of contaminants
are not presently moving off site.  Dilution factors were applied
to the maximum detected ditch sediment concentrations to
determine possible sediment contaminant levels downstream in
Norton Creek resulting from any past migration.  Comparison of
these levels with toxicity information indicated that possible
past migration of sediment contaminants downstream into Norton
Creek would have little effect on the aquatic biota.

For specific information on EPA's environmental and human health
evaluations, refer to the Baseline Risk Assessment portion of the
RI Report.


6.7.1  UNCERTAINTY ANALYSIS

The major uncertainties associated with the environmental
evaluation are the extrapolation of soil/ditch sediment
concentrations to actual exposures.  In addition the
extrapolation of laboratory toxicity data on pure compounds or
specific complexes to the Redwing Site, where the actual
environmental forms are unknown,  adds to the uncertainty.


6.8    RISK ASSESSMENT  SUMMARY

The health risk posed at this site is primarily from the future
use of the groundwater in both the surficial and alluvial aquifer
as a potable source.   This is due to the presence of contaminants
presently at concentrations above EPA's Maximum Containment
Levels for drinking water.  Surface soils and sediments are
subject to contamination from the continual leaching of
contaminants from the sludge which percolates to the surface.

With regard to environmental risks, there are no permanent on-
site aquatic habitats and the only on-site surface water bodies
are intermittent ditches.  The highest sediment contaminant
levels are under the lined ditch and therefore not presently
available to migrate along the surface water pathway.  Dilution
factors,  with respect to possible effects on aquatic biota on
surface water bodies downstream,  show that there would be no
adverse effect on aquatic biota from sediment contaminant levels.

                               57

-------
6.9     CHEMICALS  OF  CONCERN AND  CLEANUP LRVRT.fi

The chemicals of potential concern were determined during the
risk assessment.  All constituents detected at the Redwing Site
were initially considered as chemicals of  potential concern.   The
results of the risk assessment have provided a basis for
narrowing that list to those constituents  in the soils  which pose
a threat via the direct contact  (ingestion and inhalation)  route
and via the migration pathway to groundwater.   The chemicals
determined for the remedial investigation  to be of potential
concern to human health and the environment and their respective
protective cleanup levels for soils and sediments are presented
in Tables 18 and 19.   Additionally, Table  20 lists protective
groundwater concentrations.  These allowable post-remediation
concentrations are based upon the current  groundwater protection
standard (MCL) or where such standards are not available,  the
number is based on the results of the risk assessment which
constitute health-based cleanup goals.
6.10
CONCLUSION
Actual or threatened releases of hazardous substances  from this
Site, if not addressed by implementing the response action
selected in the ROD may present an imminent and substantial
endangerment to public health,  welfare,  or the environment.
        TABLE 18 - CLEANUP LEVELS FOR SUBSURFACE SOIL
CONTAMINANTS OF CONCERN
4, 4 '-DDT **
ACETONE
ALDRIN
ALPHA-BHC
CHLOROFORM
. CHROMIUM
DIELDRIN
GAMMA -BHC (LINDANE)
METHYLENE CHLORIDE
CONCENTRATION
RANGE
(Jig/kg)
0.48 - 140
3 - 2,300
0.67 - 200
0.1 - 4.7
4 - 46,000
2,800 - 52, 900
0.57 - 6.3
2.5 - 54
3-89
CLEANUP
LEVEL *
(Jig/kg)
566
36
4
0.5
70
47,000
0.1
3.2
0.6
                                58

-------
       TABLE 18 - CLEANUP LEVELS FOR SUBSURFACE SOIL
CONTAMINANTS OF CONCERN
NICKEL
VANADIUM **
VERNOLATE
CONCENTRATION'
RANGE
(ug/kg)
3,000 - 36,500
1,800 - 50,200
2 - 130,000
CLEANUP
LEVEL *
(ug/kg)
30,000
156,000
55
 * Cleanup levels  are based on groundwater protection.  If
lead is detected  in  subsurface soils not already  cited for
remediation because cleanup levels above are exceeded, and the
concentration of lead is above 541 OOP liq/kcr, then
groundwater and soil characterization will be conducted to
determine if soil  cleanup is required for the protection of
groundwater at 15ng/l, the current action level  for lead in
groundwater.

** Concentrations  of these site related contaminants were
detected above cleanup levels in groundwater during the
remedial investigation but not in the subsurface soils. Their
current existence  in subsurface soils above cleanup levels
must be verified.
TABLE 19 - CLEANUP LEVELS FOR SURFACE SOIL AND SEDIMENTS
CONTAMINANTS OF CONCERN
BENZO (A) PYRENE
BENZO (B) FLUORANTHENE
BENZO (A) ANTHRACENE
CARBON TETRACHLORIDE
CHRYSENE
CONCENTRATION
RANGE
(jig/kg)
73 - 3,200
230 - 7,400
67 - 7,200
110,000
93 - 3,800
CLEANUP LEVEL
(jig/kg) *
94.9
540 1
1,025
9,590
362
* Based on risk from inhalation or ingestion
                              59

-------
TABLE 20 - CLEANUP LEVELS FOR GROUNDWATER
CONTAMINANTS OF CONCERN
4,4' -DDT
ACETONE
ALDRIN
ALPHA-BHC
BERYLLIUM
BIS (2- ETHYLHEX YL ) PHTHALATE
CARBON DISULFIDE
CHLOROFORM
CHROMIUM
DIELDRIN
GAMMA - BHC (LINDANE)
METHYLENE CHLORIDE
NICKEL
VANADIUM
VERNOLATE
CONCENTRATION
RANGE (Hg/1)
0.86
10,000 - 2,100,000
0.11 - 0.47
0.044 - 0.15
1.3 - 9.5
2 - 710
9 - 5,500
2,900 - 27,000
6.2 - 355
0.012 - 1.1
O.OL- 0.7
330 - 650
28.7 - 301
6.6 - 580
1.1 - 140
CLEANUP LEVEL
(Hg/1) * .(
0.158
1,120
0.00317
0.00855
4.00
6.00
47.6
100
50
.00337
0.2
5
100
78.1
11.2
* Based on MCL or Risk Assessment
                  60

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7.0
DESCRIPTION OF ALTERNATIVES
The Feasibility Study Report evaluated possible alternatives for
remediation of conditions at the Redwing Site.  A total of six
(6) alternatives have been established for detailed analysis
consideration.  These alternatives were selected to provide a
range of remedial actions for the Redwing Site.
1.
2.
3.
4.
5.
6.
No Action
Continuing Response Action
Collection of Source Material and Off-
Site Treatment Disposal; Extraction of
Groundwater with On-Site Treatment and
Off-Site Disposal to a POTW
RCRA Cap
Concrete Cap
Collection of Source Material and On-
Site Treatment Disposal; Extraction of
Groundwater with On-Site Treatment and
Off-Site Disposal to a POTW
7.1
ALTERNATIVE No. 1 - No Action
The no action alternative is carried through the screening
process as required by the National Oil and Hazardous Substances
Pollution Contingency Plan  (NCP).   This alternative is used as a
baseline for comparison with other developed alternatives.  Under
this alternative the seep inspection and removal program
currently being conducted by Redwing under a removal order would
cease.  Sludge seeps would be allowed to emerge unchecked and the
EPA would not take further action to minimize the impact that
soil contamination would have on the groundwater.  Contaminants
in the soil would continue to leach into the groundwater.  Levels
of contamination would continue to exceed groundwater protection
standards.  The overall remedial action levels would not be
achieved by utilizing this alternative.  There is no cost
associated with this alternative since no actions would be
conducted.
7 .2     ALTERNATIVE No.  2  -  Inspection  and  Seep  Removal with
        Groundwater Monitoring

This alternative consists of inspection for and removal of
surfaced seeps of sludge along with monitoring surficial and
                                61

-------
alluvial groundwater quality and movement.  This alternative
contains some of the elements currently being conducted under an
Administrative Order by Redwing Carriers, Inc.  Groundwater
remediation is not addressed by this alternative.  Under this
alternative, institutional controls and natural attenuation of
the contamination within the surficial and alluvial groundwater
would be the mechanism to prevent exposure and groundwater
remediation respectively.  The estimated costs for this
alternative is $558,000 for the thirty (30) years of
implementation.  However, the timeframe for natural attenuation
to occur has not been determined.
7 .3     ALTERNATIVE No.  3 - Excavation of Source Material,
        Extraction of Surficial Groundwater with Off-Site
        Treatment and Disposal of each.   Groundwater Monitoring
        of the Alluvial  Aquifer.

This alternative involves  excavation and transportation of soil
and sludge  (i.e. source material) to an off-site treatment and
disposal facility.  Additionally, extraction and disposal of
contaminated surficial groundwater would be required.
Groundwater monitoring of  the  alluvial aquifer would be
implemented to assure attenuation of the contaminant levels.
Source material and groundwater pre-treatment may be required
prior to disposal.  This may require thermal and biological
treatment of soils and groundwater, respectively.  Excavated
subsurface soils may require dewatering and stabilization prior
to land disposal.  This water  will be analyzed and
treated/disposed of in an  appropriate manner.  Excavation may be
accomplished with or without the removal of buildings or
structures in areas requiring  excavation. Currently, there is no
evidence that contamination exists under the buildings.  However,
if contamination is found  during the remedial design appropriate
action, which may involve  the  demolition of some buildings, will
be undertaken.  EPA will consult the public before taking this
action.

The areas of soil and sludge would be excavated.  Residents would
be temporarily relocated during the period of excavation.  Source
materials would be moved to a  staging area on-site prior to being
hauled off-site.  Some of  the  excavated soils will be removed
from the saturated zone and will require dewatering.  Sidewalk
slabs and pavement areas may be contaminated and thus require
removal.  Excavated areas  would be backfilled with clean
material.  The excavated material would be sorted and
characterized to determine if  treatment is required before land
disposal.  If treatment is required it will be conducted off-site
at an approved facility.   All  excavated soil, source material,
sludge, and contamina- =d debris will be disposed of off-site at
an approved facility.   :t  is estimated -.nat the excavation and
removal would be accoir ..Dished  in 18 months.

                                62

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Alternative 3 also includes extraction and active treatment of
the surficial groundwater.  Under this alternative contaminated
groundwater would be extracted, treated on-site and discharged to
the POTW or to a nearby surface water body if appropriate limits
can be met.  The alluvial groundwater will be monitored to insure
that chemicals of concern decrease to cleanup levels.  If natural
attenuation does not progress at a rate to meet cleanup levels
within the timeframe of active treatment to the surficial
aquifer, the remedial design will be modified to include active
treatment of alluvial as well as surficial groundwater.

An installed network of extraction wells and french drains will
extract contaminated groundwater from the surficial aquifer for
on-site treatment.  The treatment system will use a biotreatment
process and sand/activated carbon filtration to treat more
heavily contaminated groundwater.  After concentrations decrease
the system may be adjusted to reduce the rate of extraction or to
a point where only the filtration system is required.  The
groundwater may also contain contaminants which may not be
effectively treated using a biotreatment process.  These
contaminants may require a supplemental treatment step.  Residual
constituents in the biotreatment sludges or spent carbon would be
disposed of off-site at an approved facility.

It is predicted that 12 million gallons of surficial groundwater
must be treated to reduce concentrations to cleanup levels.  The
groundwater cleanup time frame is estimated to be 7 years.  The
time may be shortened by putting nutrients into the surficial
aquifer to enhance biodegradation.

This alternative would provide overall protection for any present
or future uses of the property.  The estimated implementation
timeframe for this alternative is seven (7) years.  The estimated
cost for this alternative is $7,002,562.


7.4     ALTERNATIVE No.  4  -  RCRA Cap.  Extraction  of  Surficial
        Groundwater for  On-site Treatment,  and Groundwater
        Monitoring for the Alluvial-Aquifer.

This alternative involves placement of a RCRA cap over the
eastern half of the apartment complex, extraction and on-site
treatment of the surficial groundwater and monitoring of the
alluvial aquifer.  Construction of the RCRA cap will require the
demolition of approximately six buildings and the capped area
would be fenced.  As part of this alternative,  the contaminated
surficial groundwater will be extracted in order to prevent
further migration of contamination.  Groundwater will be treated
on-site and subsequently discharged.   The integrity of the cap
would be maintained indefinitely with monitoring of the surficial
and alluvial aquifer.  Surficial groundwater extraction and
treatment is expected to reduce contaminant concentrations below

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cleanup levels within eleven  (11) years.  The estimated cost for
this alternative is $3,870,460.


7 .5     ALTERNATIVE No.  5 - Concrete Cap.  Extraction and Off-Site
        Treatment and Disposal of Surficial  Groundwater and
        Monitoring of the Alluvial Acruifer.

This alterative consists of the placement of a concrete cap over
sections of the eastern half  open grassy areas of the Redwing
Site,- surficial groundwater extraction with off-site treatment
and disposal and monitoring of the groundwater in the alluvial
aquifer.

The concrete cap would be  constructed without the demolition of
any apartment buildings.   The cap could be placed around the
existing apartment units which are in source areas of
contamination.  The cap would be constructed such that its
integrity can be maintained and upward movement of subsurface
sludge would be inhibited.

The cap would be designed  with sufficient thickness and joint
impermeability to control  seeps of sludge and potential vapor
emissions.  The cap would  be  designed and constructed above grade
over the current ground surface of the Redwing Site such that it
would eliminate migration  of  sludge around the edges of the cap.
The capped area would remain  accessible for use by the apartment
residents.  To maintain the existing functional use of the
Redwing Site, recreational-use improvements would be incorporated
into the cap design.

The contaminated surficial groundwater would be extracted and
treated on-site, as necessary, for disposal to the POTW.
Implementation of groundwater monitoring of the alluvial aquifer
and maintenance of the cap would be required.  The estimated
timeframe for remediation  of  the surficial groundwater is ten
(10) years.  Natural attenuation would be the mechanism for
remediation of the alluvial groundwater.  The cap would be
maintained indefinitely.   The estimated cost of this alternative
is $2,233,751.


7.6     ALTERNATIVE No 6 - Excavation of  Source Material  and
        Surficial Groundwater with On-Site Treatment/Disposal.
        Groundwater Monitoring of the Alluvial Aquifer.

This alternative combines  source material excavation with on-site
treatment of source material  and surficial groundwater.
Temporary relocation for approximately 2 years would be required
during excavati'. - and treatment of the source material.
Currently, the     3 no evidence that contamination exists under
the buildings.     //ever,  if contamination is found during the

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 remedial design appropriate action,  which may involve the
 demolition of some buildings,  will be undertaken.   EPA will
 consult the public before taking this action.

 The following primary on-site  treatment processes  will be
 implemented:   1)  soil washing/flushing,  2)  filtration,  and 3)
 biotreatment.  The excavated source material will  be stockpiled
 and washed with a compatible washing agent as a volume reducing
 treatment step.  The washed soil would be then dewatered and
 analyzed before backfilling into the excavation.   The spent wash
 solution and soil fines  would  be pumped through a  filtration
 system to further separate and concentrate the dissolved and
 suspended constituents.   The filtrate may be reused as wash
 solution.  The filtered  constituents will then be  sent to the
 biotreatment  unit.   The  biotreatment process will  be designed  to
 create a favorable environment for microorganisms  which are
 capable of degrading the compounds of concern at the Redwing
 Site.

 In addition to the soil  washing,  other technologies (ex-situ soil
 flushing, gravity separation and ex-situ bioremediation)  may also
 be used in addition to or instead of ex-situ -soil  washing, if
 during the remedial design these technologies are  effective in
^reducing soil contaminant concentrations and are determined to be
 cost effective.

 Alternative 6 also includes extraction and active  treatment of
 surficial groundwater.   Under  this alternative,  contaminated
 groundwater would be extracted,  treated on-site and discharged to
 the POTW or to a nearby  surface waterbody if appropriate limits
 can be met.  The alluvial groundwater will be monitored to insure
 that chemicals of concern decrease to cleanup levels.   If natural
 attenuation does not progress  at a rate to meet cleanup levels
 within the timeframe of  active treatment to the surficial
 aquifer,  the remedial design will be modified to include active
 treatment of  alluvial as well  as surficial groundwater.

 An installed network of  extraction wells and french drains will
 extract contaminated groundwater from the surficial aquifer for
 on-site treatment.   The  treatment system will use  a biotreatment
 process and sand/activated carbon filtration to treat more
 heavily contaminated groundwater.  After concentrations decrease
 the system may be adjusted to  reduce the rate of extraction or to
 a point where only the filtration system is required.   The
 groundwater may also contain contaminants which may not be
 effectively treated using a biotreatment process.   These
 contaminants  may require a supplemental treatment  step.   Residual
 constituents  in the biotreatment sludges or spent  carbon would be
 treated prior to disposal.

 It is  predicted that 12  million gallons of surficial groundwater
 must be treated to reduce concentrations to cleanup levels.  The

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groundwater" cleanup  time frame is estimated to be 7.1 years.  The
time may be shortened by putting nutrients into the surficial
aquifer to enhance biodegradation.

The estimated timeframe for treatment of the source material and
groundwater is 2 and 7 years respectively.  The estimated cost of
this alternative is  $6,168,452.


7.7     ARARS AND TBCS

The remedial action  for the Redwing Site, under CERCLA Section
121 (d) , must comply with federal and state environmental laws
that are either applicable or relevant and appropriate (ARARs).
Applicable  requirements are those standards,  criteria or
limitations promulgated under federal or state law that
specifically address a hazardous  substance, pollutant,
contaminant, remedial action, location or other circumstance at  a
CERCLA site.  Relevant and appropriate requirements are those
that,  while not applicable, still address problems or situations
sufficiently similar to those encountered at the site that their
use is well suited to the particular site.  To-Be-Considered
Criteria (TBCs) are  non-promulgated advisories and guidance'that
are not legally binding but should be considered in determining
the necessary level  of cleanup for protection of health or the
environment.

While TBCs do not have the status of ARARS, EPA's approach to
determining if a remedial action is protective of human health
and the environment  involves consideration of TBCs along with
ARARs.

The affected groundwater in the aquifers beneath the Redwing Site
have been classified as Class IIB for the surficial groundwater
and Class IIA for the alluvial aquifer.  Class IIB groundwater is
a potential drinking watei source althoug.. the groundwater may
not be currently used as such.' Class IIA groundwater is a
current source of drinking water.  It is EPA's policy that
groundwater resources be protected and restored to their
beneficial uses.  The six remedial alternatives with the
exception of alternative one (no action) have components which
may to some degree promote the beneficial use of the aquifers.  A
complete definition  for groundwater classification is provided in
the Guidelines for Ground-water Classification under the EPA
Ground Water Protection Strategy. Final Draft, December 1986.

The action level for lead in groundwater (IS^ig) is the only TBC
that has been identified at this time.  The potential action
specific, chemical s --rific and State ARARs are presented in .
Tables 21A, B and C.
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TABLE 21A -
         ACTION-SPECIFIC FEDERAL ARARS  FOR THE REDWING
         SITE
CLEAN WATER ACT - 33 U. S. C. 1251-1376
R & A
40 CFR Part 122, 125 -
National Pollutant
Discharge Elimination
System
Requires permits for the
discharge of pollutants for any
point source into waters of the
United States.
      40  CFR Part  403  - National
      Pretreatment Standards
                           Sets  standards  to  control
                           pollutants which pass through or
                           interfere with  treatment
                           processes in public  treatment
                           works or which  may contaminate
                           sewage  sludge.
RESOURCE CONSERVATION AND RECOVERY ACT - 42 D.S.C. 6901-6987
R & A
40 CFR Part 257 - Criteria
for Classification-of
Solid Waste Disposal
Facilities and Practices
Establishes criteria for use in
determining which solid waste
disposal facilities and
practices pose a reasonable
probability of adverse effects
on public health or the
environment.
R & A
40 CFR Part 262 -
Standards Applicable to
Generators of Hazardous
Waste
Establishes standards for
generators of hazardous wastes
      40 CFR  Part  263  -
      Standards Applicable  to
      Transportation of
      Hazardous Waste
                           Establishes  standards which
                           apply  to  transporters of
                           hazardous waste within  the U.S.
                           if  the transportation requires a
                           manifest  under 40  CFR PaRt 262.
R & A
40 CFR Part 264 -
Standards for Owners and
Operators of Hazardous
Waste Treatment, Storage
and Disposal (TSD)
Facilities
Establishes minimum-national
standards which define the
acceptable management of
hazardous wastes for owners and
operators of facilities which
treat, store or dispose of
hazardous wastes.
      40  CFR Part  268  -  Land
      Disposal
                           Identifies  hazardous  wastes  that
                           are  restricted from land
                           disposal  and describes  those
                           circumstances under which an
                           otherwise prohibited  waste may
                           be land disposed.
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TABLE 21A -
ACTION-SPECIFIC  FEDERAL ARABS  FOR  THE REDWING
SITE
SAFE DRINKING WATER  ACT
       40  CFR  Parts  144  - 147
       Underground Injection
       Control Regulations
                     Provides  for  protection of
                     underground sources of  drinking
                     water
HAZARDOUS MATERIALS  TRANSPORTATION ACT - 49  U.S.  C 1801-1813
       40  CFR  Parts  107,%171-177
       - Hazardous Materials
       Transportation Regulations
                     Regulates transportation of
                     hazardous materials.
A. = APPLICABLE REQUIREMENTS WHICH WERE PROMULGATE? UNDER FEDERAL LAW TO SPECIFICALLY ADDRESS A HAZARDOUS SUBSTANCE,
POLLUTANT, CONTAMINANT, REMEDIAL ACTION LOCATION C- THER CIRCUMSTANCE AT THE REDWNC SITE.

R b A. * RELEVANT AND APPROPRIATE REQUIREMENTS WHO- MOLE THEY ARE NOT 'AT 'UCABLE" TO A HAZARDOUS SUBSTANCE. POLLUTANT,
CONTAMINANT, REMEDIAL ACTION. LOCATION, OR OTHER CIRCUMSTANCE AT THE RED WNC SITE, ADDRESS PROBLEMS OR SITUATIONS SUmdlXTVt
SIMILAR TO THOSE ENCOUNTERED AT THE REDWING SITE THAT THEIR USE IS WELL SUITED TO THE SITE.
TABLE 21B - CHEMICAL-SPECIFIC FEDERAL ARARS FOR THE REDWING
SITE
CLEAN WATER ACT - 33 U. S. C. 1251-1376
R & A
A
40 CFR Part 131 - Ambient
Water Quality Criteria
requirements
40 CFR Part 403 - National
Pretreatment Standards
Suggested ambient standards for
the protection of human health
and aquatic life.
Sets standards to control
pollutants which pass through or
interfere with treatment
processes in publicly-owned
treatment works or which may
contaminate sewage sludge.
RESOURCE CONSERVATION AND RECOVERY ACT - 42 U.S.C. 6901-6987
R & A
40 CFR Part 261 -
Identification and Listing
of Hazardous Wastes
Defines those solid wastes which
are subject to regulation as
hazardous wastes under 40 CFR
Parts 263-265 and Parts 124,
2~0, and 271.
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TABLE 218 - CHEMICAL-SPECIFIC FEDERAL ARARS FOR THE REDWING
SITE
R & A
40 CFR Part 262 -
Standards Applicable to
Generators of Hazardous
Waste
Establishes standards for
generators of hazardous waste.
CLEAN AIR ACT - 42 USC Section 7401 - 7642
R & A
40 CFR Part 50 - National
Primary and Secondary
Ambient Air Quality
Standards
Establishes standards for
ambient air quality to protect
public health and welfare.
SAFE DRINKING WATER ACT - 40 USC Section 300
R & A
R & A
40 CFR Part 141 - National
Primary Drinking Water
Standards
PL No. 99-339 100 Stat.462
(1986) - Maximum
Contaminant Level Goals
(MCLGs)
Establishes maximum contaminant
levels (MCLs) which are health-
based standards for public water
systems .
Establishes drinking water
quality goals set at levels of
no known or anticipated adverse
health effects with an adequate
margin of safety.
A = APPLICABLE REQUIREMENTS WHICH WERE PROMULGATED UNDER FEDERAL LAWTO SPECIFICALLY ADDRESS A HAZARDOUS SUBSTANCE.
POLLUTANT, CONTAMINANT, REMEDIAL ACTION LOCATION OR OTHER CIRCUMSTANCE AT THE REDWING SITE.
R fr A = RELEVANT AND APPROPRIATE REQUIREMENTS WHICH WHttE THEY ARE NOT "APPL/CABLE" TO A HAZARDOUS SUBSTANCE, POLLUTANT.
CONTAMINANT, REMEDIAL ACTION, LOCATION. OR OTHER CIRCUMSTANCE AT THE RED WNC SITE, ADDRESS PROBLEMS OR SITUATIONS SUFFICIENTLY
SIMILAR TO THOSE ENCOUNTERED AT THE REDWING S/TE THAT THEIR USE IS WELL SUITED TO THE SITE.
     TABLE  21C -STATE OF ALABAMA ARARS  FOR THE REDWING SITE
        REGULATION
  APPLICABLE  OR
   RELEVANT AND
   APPROPRIATE
     BASIS FOR
  DETERMINATION
Alabama Water Pollution
Control Act  code  of
Alabama, Title 22,
Chapter 22  - Water
Improvement  Commission)
APPLICABLE REQUIREMENT WHICH WAS
PROMULGATED BY THE STATE OF
ALABAMA TO SPECIFICALLY ADDRESS A
HAZARDOUS SUBSTANCE, POLLUTANT,
CONTAMINANT. REMEDIAL ACTION
LOCATION OR OTHER CIRCUMSTANCE
AT THE REDWING SITE.
Establishes
standards  for
limits of
pollution  and
quality of water.
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       TABLE 21C  -STATE OP ALABAMA ARARS FOR THE REDWING SITE
  Alabama National
  Pollutant  Discharge
  Elimination System
  Permit Regulations
   (Alabama Administrative
  Code, Department  of
  Environmental
  Management, Water
  Division,  Water Quality
  Program, Chapter  335-6-
  6 NPDES; adopted
  October 19, 1979;
  amended January 24,
  1989 v-
  Alab -a  Primary
  Dri.  _:ig Water
  Sta:. .^rds (Alabama
  Administrative Code,
  Department of
  Environmental
  Management,  Water
  Division - Water supply
  Program,  Chapter 335-7-
  2-Primary Drinking
  Water Standards;
  Adopted  January  4,
  1989)
APPLICABLE REQUIREMENT WHICH WAS
PROMULGATED BY THE STATE OF
ALABAMA TO SPECIFICALLY ADDRESS A
HAZARDOUS SUBSTANCE. POLLUTANT,
CONTAMINANT. REMEDIAL ACTION
LOCATION OK OTHER CIRCUMSTANCE
AT THE REDWINC SITE.
State
administered
permit program
comparable to  the
National
permitting
system.
APPLICABLE REQUIREMENT WHICh
PROMULGATED BY THE STATE OF
ALABAMA TO SPECIFICALLY ADDRL
HAZARDOUS SUBSTANCE. POLLUTE.
CONTAMINANT. REMEDIAL ACTION
LOCATION OR OTHER CIRCUMSTANCE
AT THE REDWINC SHE.
Applicable to
water  systems
required to
monitor for
various
contaminants.
  Maximum  Concentration
  of Constituents  for
  Groundwater Protection
   (Alabama Administrative
  Code, Department of
  Envi ronment a1
  Management, Hazardous
  Waste Program, Chapter
  335-14-5.06-Releases
  from Solid Waste
  Management Units;
  adopted  June 8,m 1983;
  amended  January  25,
  1992)
RELEVANT AND APPROPRIATE
REQUIREMENT WHICH WHILE IT IS NOT
•APPLICABLE ' TO A HAZARDOUS
SUBSTANCE, POLLUTANT,
CONTAMINANT, REMEDIAL ACTION.
LOCATION, OR OTHER CIRCUMSTANCE
AT THE REDWINC SITE. ADDRESS
PROBLEMS OR SITUATIONS
SUmaiNTVf SIMILAR TO THOSE
ENCOUNTERED AT THE REDWINC SITE
THAT THEIR USE IS WELL SUITED TO
THE SITE.
Applies to
owners/operators
of  facilities
that  transport,
store,  or dispose
of  hazardous
waste.
8.0     SUMMARY OF COMPARATIVE ANALYSIS OF  ALTERNATIVES

This  section  of the  ROD provides the  basis for  determining which
                                   70

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alternative provides the best balance with respect to the
statutory balancing criteria in Section'121 of CERCLA, 42 U.S.C.
Section 9621, and in the NCP, 40 C.F.R, Section 300.430.  The
major objective of the FS was to develop, screen and evaluate
alternatives for the remediation of the Redwing Site.  A wide
variety of alternatives and technologies were identified as
candidates to remediate the contamination at the Redwing Site.
These were screened based on their feasibility with respect to
the contaminants present and the site characteristics.  After the
initial screening, the remaining alternatives/technologies  were
combined into potential remedial alternatives and evaluated in
detail.  The remedial alternative was selected from the screening
process using the following nine evaluation criteria:

• Overall protection of human health and the environment;

• Compliance with applicable and/or relevant Federal or State
  public health or environmental standards;

• Long-term effectiveness and permanence;

• Reduction of toxicity, mobility or volume of hazardous
  substances or contaminants;

• Short-term effectiveness or the impacts a remedy might have on
  the community, workers or the environment during the course of
  implementation;

• Implementability,  that is, the administrative or technical
  capacity to carry out the alternative;

• Cost-effectiveness considering costs .for construction,
  operation,  and maintenance of the alternative over the life of
  the project,  including additional costs should it fail;

• Acceptance by the State and

• Acceptance by the Community.


The NCP categorizes the nine criteria into three groups:

(1)  Threshold Criteria - overall protection of human health and
     the environment and compliance with ARARs (or invoking a
     waiver)  are threshold criteria that must be satisfied in
     order for an alternative to be eligible for selection;

(2)  Primary Balancing Criteria - long-term effectiveness and
     permanence; reduction of toxicity, mobility or volume;
     short-term effectiveness;  implementability and cost are
     primary balancing factors  used to weigh major trade-offs
     among alternative hazardous waste management strategies; and

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 (3)  Modifying Criteria - state and community acceptance are
     modifying criteria that are formally taken into account
     after public comments are received on the proposed plan and
     incorporated in the ROD.

The selected alternative must meet the threshold criteria and
comply with all ARARs or be granted a waiver for compliance with
ARARs.  Any alternative that does not satisfy both of these
requirements is not eligible for selection.  The Primary
Balancing Criteria is the technical criteria upon which the
detailed analysis of alternatives is primarily based.  The final
two criteria, known as Modifying Criteria, assess the public's
and the state agency's acceptance of the alternative.  Based on
these final two criteria,  EPA may modify aspects of a specific
alternative.

The following analysis is a summary of the evaluation of
alternatives for remediating the Redwing Carriers Inc.,
 (Saraland) Superfund Site under each of the criteria.  A
comparison is made between each of the alternatives for
achievement of a specific criterion.


8.1     THRESHOLD CRITERIA

Overall Protection of Human Health and the Environment

Each of the alternatives with the exception of Alternative 1 and
2 would provide protection of human health and the environment by
minimizing or controlling the risk associated with the
contaminated soils through institutional controls and treatment
or containment.  Alternative 2 would rely on an ongoing
maintenance endeavor to achieve satisfactory protection from
direct contact with the source material, but is ineffective for
protection of groundwater.  Therefore, cleanup levels for
groundwater would not be achieved with Alternative 2.  The
containment alternatives 4 and 5 would rely on continued
maintenance to achieve satisfactory protection.  These two
alternatives provide overall protection by isolating the source
material from potential direct contact, ingestion or inhalation.
The surficial groundwater pump and treat action may eventually
achieve the remedial objective for the surficial groundwater,
however, the source material would remain.  Therefore,  overall
protection may not be achieved with alternatives 4 and 5.  Those
alternatives involving excavation,  (Alternatives 3 and 6),  would
minimize the"majority of the risk by removing and treating the
principal source of the soil and groundwater contamination.
Alternatives 3 and 6 would provide the best overall protection
because of removal and treatment of contaminated soils and
groundwater.

Compliance with ARARs

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Each of the remaining alternatives  (alternatives 3,. 4, 5 and 6)
could comply with all Federal or State ARARs or justify a waiver.
Chemical specific ARARs for groundwater would be met through
compliance with the groundwater protection standards  (ie., MCLs).


8.2     PRIMARY BALANCING  CRITERIA

Long-Term Effectiveness and Permanence

The long-term effectiveness is demonstrated by treatment of
contaminated soils and groundwater using proven technologies thus
eliminating potential exposure and long term maintenance.

Alternatives 3, 4, 5 and 6 would provide long-term effectiveness
through limiting the migration of contamination or treatment of
the contaminated soils at the Redwing Site'.  For alternatives 4
and 5, long-term effectiveness relies on proper cap maintenance
and continued extraction and treatment of groundwater.
Implementation would require restricted use of the affected
groundwater until the remedial cleanup goals are achieved.  In
Alternative 4, the contaminants are contained on-site in a RCRA
landfill while Alternative 5 uses a concrete cap to prevent
infiltration of rainwater into the contaminated soils.  The
long-term effectiveness of Alternative 4 and 5 is satisfactory
since continuous inspection and monitoring would be required
while allowing for the use of the property as an apartment
complex.  Alternatives 3 and 6 provide the best level of
long-term effectiveness because treatment would be utilized to
permanently remediate the soils and groundwater.

Reduction of Toxicity, Mobility or Volume Through Treatment

Alternatives 4 and 5 would isolate the contamination from the
environment thus minimizing the forces which drive contaminant
mobility.  However, toxicity and volume would not be affected by
Alternative 4 or 5.  Alternatives 3 and 6 would reduce the
mobility, toxicity, and volume of contaminants which are above
acceptable risk levels.

Short-Term Effectiveness

Alternatives 3, 4, 5 and 6 will require varying amounts of time
to implement.  None are immediately implementable or effective.
Threshold toxicity criteria would not be exceeded by implementing
Alternatives 3 and 6.  Health risks to remedial workers is
unlikely since appropriate monitoring and engineering controls
will be applied.  Of the alternatives evaluated, Alternatives 3
and 6 are most effective because contaminated soils and
groundwater would be removed and treated.  However Alternative 6
would require a longer implementation time period because of the
requirement for on-site treatment,  thus reducing its short term

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effectiveness.

Xmplementability

Alternatives 3, 4, 5 and 6 are equally implementable but may
require the temporary/permanent relocation of on-site residents
to allow for excavation and construction.  Alternative 4 may
require permanent demolition of the on-site buildings located in
the capped area.  Complexities in the implementation of
alternatives 3, 4 and 6 exist because remediation impacts on the
apartment complex residents.  Alternative 5 (Concrete Cap) design
would be complex to allow for the continued use of the property
as a pleasant living environment.

Cost

All of the alternatives which involve on-site treatment
components have higher capital and present worth cos- •.   However,
the cost associated with Alternatives 3 and 6 (exca-   ion with
on-site/off-site treatment) would not extend into th . operation
and maintenance period except for a limited time to achieve the
groundwater cleanup goals.  Alternatives 4, and 5 would require
expenditure of funds for an indefinite period of time.


Cost Summary

Since no action would be taken under alternative 1, no additional
costs would be incurred.  The other alternatives range in cost as
shown below.  Temporary relocation costs are not included in cost
estimates for alternatives 3 and 6.  Capital costs include direct
and indirect costs.  Operation and Maintenance costs are present
worth dollars based on 5% discount rate.  Implementation present
worth is the sum of capital cost3 and the present worth of the
total Operation and Maintenance expenditures.


Alternative   Capital Cost      O&M Costs     Present Worth Costs
    2          $    76,000        $   482,000        $   558,000
    3          $6,484,763        $   518,000        $7,002,562
    4          $2,065,755        $1,805,000        $3,870,000
    5          $1,811,017        $   423,000        $2,233,751
    6          $5,951,165        $   217,000        $6,168,000


8.3     MODIFYING CRITERIA

State Acceptance

The State of Alabama has concurred with the selection of
Alternative 3 to remediate the Redwing Site.  The State of
Alabama expressed concern that the originally proposed

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Alternative 6 would not be the appropriate option for the Redwing
Site.  EPA took the state agency's concern into account and
reevaluated the preferred alternative.

Community Acceptance

At the August 11, 1992 public meeting the primary concern
expressed by the community was that the sludge and contaminated
materials be removed from the Redwing Site.  Implementation of an
off-site option  (Alternative 3) will provide a protective
remedial alternative and satisfy the primary community concern.


9.0     THE  SELECTED REMEDY

Based upon consideration of the requirements of CERCLA, the NCP,
the detailed analysis of alternatives and public and state
comments, EPA has selected a source control and groundwater
remedy for this site.   The risk associated with this site has
been calculated at 10"6 at the completion of this remedy.  This
is determined to be protective of human health and the
environment.  The total present worth cost of the selected
remedy, Alternative #3, is estimated at $7,002,562.

A.      Source Control

Source control remediation will address the contaminated soils,
sludges and sediments at the Site.  Source control shall include
excavation of soils, sludges and sediments, staging,  dewatering,
characterization, and transportation to an approved disposal
facility.
                      •
  A.I.  The  manor components of source  control  to be  implemented
        include:

        Soils, sludges  and related materials shall be excavated
        at the Redwing  Site and staged  on-site  for off-site
        disposal.  Excavation  shall occur in all areas  of  site
        related  contamination  above cleanup levels.   The concrete
        liners in the southern and eastern  ditches shall be
        removed  and  excavation shall occur  along past and  present
        drainage pathways from the Redwing  Site.  Excavation
        shall continue  until the  remaining  soils and  sediments
        material achieve the levels specified in the  tables
        below.

        In order to  comply with ARARs,  source material may
        require  pre-treatment  prior to  disposal.  This may
        require  thermal treatment  of soils.  Excavated subsurface
        soils may require dewatering and stabilization prior  to
        land disposal.  The water  from  the  saturated  soils must
        be analyzed  and treated/disposed of in  an appropriate

                               75

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manner.

Excavation may be accomplished with or without the
removal of buildings or structures.  While the areas of
soil and sludge  (i.e. source material) are excavated
residents will be temporarily relocated.  Source
materials will be excavated and moved to a staging area
on-site prior to being hauled off-site.  Some of the
excavated soils will be removed from the saturated zone
and will require dewatering.  Sidewalk slabs and pavement
areas may be contaminated and thus require removal.
Excavated areas will be backfilled with clean material.
The excavated material will be sorted and characterized
to determine if treatment is required before land
disposal.  If treatment is required it will be conducted
off-site at an approved facility.  All excavated soil,
source material, sludge, and contaminated debris will be
disposed of off-site at an approved facility.

Excavation of the surface soils and along the drainage
pathways shall continue until the levels identified in
the table below are met.
TABLE 22A SURFACE SOIL AND SEDIMENT
EXCAVATION LEVELS
CONTAMINANT
BENZO (A) PYRENE
BENZO (B) FLUORANTHENE
BENZO (A) ANTHRACENE
CARBON TETRACHLORIDE
CHRYSENE
EXCAVATION
LEVEL
(jig/kg)
94.9
540
1,025
9,590
362
Excavation of materials shall occur in the subsurface
soils contaminated with chemical concentrations above the
levels identified in the table below*:
                        76

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TABLE 22B SUBSURFACE SOIL EXCAVATION LEVELS
CONTAMINANT
4,4' -DDT
ACETONE
ALDRIN
ALPHA -BHC
CHLOROFORM
CHROMIUM
DIELDRIN
GAMMA- BHC (LINDANE)
METHYLENE CHLORIDE
NICKEL
VANADIUM
VERNOLATE
EXCAVATION
LEVEL
(jig/kg)
566
36
4
0.5
70
47,000
0.1
3.2
0.6
30,000
156,000
55
             If lead is detected in  subsurface soils not
             already cited for remediation because the cleanup
             levels above have been exceeded, and the
             concentration of lead is greater than 54j 00Dug/kg;
             then groundwater and soil characterization will be
             conducted to determine if soil cleanup is required
             for the protection of groundwater at 15|ag/l, the
             current action level for lead in groundwater.
A.2   Treatment  of excavated material

      The excavated material will  be sorted and characterized
      for RCRA hazardous  waste characteristics,  to  determine if
      thermal  or other treatment is  required before land
      disposal.  If treatment is required it will be conducted
      off-site at an approved facility.
A.3 .   Performance Standards

      The performance standards  for this  component  of  the

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        selected remedy include,  but are not limited to,  the
        following excavation and treatment standards:

        a.   Excavation Standards:

         Excavation shall continue until the remaining soil and
         material achieve the concentration levels identified in
         Table 22A and 22B of the previous section.  All
         excavation shall comply with ARARs, including,  but not
         limited to OSHA and state standards.  Testing methods
         approved by EPA shall be used to determine if the
         concentration levels have been achieved.

        b.   Treatment Standards:

         . -1 excavated soils, sludges and related materials will
         cisposed of at an appropriate approved facility.  Pre-
         treatment may be required prior disposal.  Treatment
         will be conducted at an approved facility.


B.      Groundwater Remediation

Groundwater remediation will address the contaminated groundwater
at the Redwing Site.  Contaminated surficial groundwater will be
extracted, treated on-sife and discharged to the POTW or to a
nearby surface waterbody if the  POTW is unavailable and if
appropriate limits can be met.   The alluvial groundwater will be
monitored to insure that chemicals of concern decrease to cleanup
levels.  If natural attenuation  does not progress at a rate to
meet cleanup levels within the timeframe of the active treatment
of the surficial groundwater, the remedial design will be
modified to include active treatment of the alluvial aquifer as
well as surficial groundwater.


  B.I.  The ma-jor components  of qroundwater  remediation  to  be
        implemented include:

        Extraction and active treatment  of the  surficial
        groundwater.   The major component  of groundwater
        remediation to be implemented at the Redwing Site is
        installation of a network of extraction wells and french
        drains to extract contaminated groundwater from  the
        surficial aquifer for on-site treatment with discharge to
        a POTW or to a nearby surface waterbody if appropriate
        limits can be met.


  B.2.  Extraction,  Treatment,  and Discharge of Contaminated
        Groundwater
                                78

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      The  treatment system will use a biotreatment process and
      sand/activated carbon filtration to treat heavily
      contaminated groundwater.  After concentrations decrease
      (estimated at 1,000,000 gallons), the system may be
      adjusted  to reduce the rate of extraction or where only
      the  filtration system is required.  The groundwater may
      also contain contaminants which will not be effectively
      treated using a biotreatment process.  These contaminants
      may  require a supplemental treatment step as identified
      during the remedial design.  Residual constituents in the
      biotreatment sludges or spent carbon will be disposed of
      at an approved facility.

      It is predicted that approximately 12 million gallons of
      surficial groundwater must be treated to reduce
      concentrations to cleanup levels which are specified in
      Table 20  of this ROD and repeated in Section B.3 below.
      The  groundwater cleanup time frame is estimated to be 7
      years.  The time may be shortened by putting nutrients
      into the  surficial aquifer to enhance biodegradation.
B.3.  Performance Standards

      Groundwater shall meet the clean-up levels specified in
      the table below at the wells in the surficial and
      alluvial aquifers at the Redwing Site.

      a.  Extraction Standards:

        Groundwater will  be  extracted from the surficial
        aquifer in a. manner  to be  determined during the
        remedial design.

      b.  Treatment Standards:

        Groundwater shall be treated until  the cleanup levels
        identified below  are attained at the wells  designated
        by EPA as compliance points:
              CONTAMINANTS OF
                  CONCERN

                  4,4'-DDT

                   ACETONE

                    ALDRIN
GROUNDWATER
  CLEANUP
    LEVEL
  (Liq/1)   *

    0.158

    1,120

   0.00317
                             79

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                CONTAMINANTS OF
                    CONCERN
                    ALPHA-BHC
                    BERYLLIUM
            BIS(2-ETHYLHEXYL)PHTHALATE
                 CARBON DISULFIDE
                    CHLOROFORM
                    CHROMIUM
                    DIELDRIN
              GAMMA - BHC (LINDANE)
                METHYLENE CHLORIDE
                     NICKEL
                    VANADIUM
                    VERNOLATE
GROUNDWATER
  CLEANUP
   LEVEL
  (Uq/1)  *
   0.00855
    4.00
    6.00
    47.6
     100
     50
    .00337
     0.2
      5
     100  .
    78.1
    11.2
           *  Based on MCL  or Risk Assessment
       c.  Discharge Standards:
          Discharges for the groundwater treatment system shall
          comply with all ARARs,  including, but not limited to,
          POTW pretreatment requirements,  substantive
          requirements of the NPDES permitting program under the
          Clean Water Act,  33 U.S.C Section 1251 et sea., and all
          effluent limits established by EPA.
       d.  Design Standards:
          The design,  construction and operation of the
          groundwater treatment system shall be conducted in
          accordance will all ARARs,  including the RCRA
          requirements set forth in 40 C.F.R. Part 264 (Subpart
          F) .
C.    Compliance Monitoring
Groundwater monitoring shall be conducted at  this site on a
monthly basis at wells designated by EPA as compliance points.
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After demonstration of compliance with Performance Standards, the
Site including soil and groundwater shall continue to be
monitored quarterly for five years.  Inspection of surface soils
for sludge seeps shall occur not less than monthly during the
summer months of the year. If monitoring indicates that the
Performance Standards set forth in Paragraph B.3 are being
exceeded at any time after pumping has been discontinued,
extraction and treatment of the groundwater will recommence until
the Performance Standards are once again achieved.  If monitoring
of the remaining soil indicates Performance Standards set forth
in Paragraph A.3 have been exceeded, the effectiveness of the
source control component will be re-evaluated.


10.0    STATUTORY DETERMINATIONS

The selected remedy satisfies the requirement of CERCLA section
121 to protect human health and the environment by eliminating
and by reducing risks posed through each pathway and population
through treatment.  The remedy ensures adequate protection of
human health and the environment.  The site risk will be reduced
to the 10"6 risk range for carcinogens, and a Hazard Index for
non-carcinogens of less than one.

No short-term risks or cross-media impacts will be caused by
implementation of the remedy.  The selected remedy satisfies the
requirement of CERCLA section 121 to comply with ARARS.

The selected remedy provides overall effectiveness proportionate
to its costs (i.e., is cost-effective).  The selected remedy
satisfies the requirement of CERCLA section 121 to utilize
permanent solutions and alternative treatment technologies or
resource recovery technologies to the maximum extent practicable.

The selected remedy provides the best balance of tradeoffs among
the alternatives with respect to the evaluation criteria.  Those
criteria that were most critical in the selection decision (i.e.,
those criteria that distinguish the alternatives most) are:
Overall protection of human health and the environment,
compliance with ARARs; reduction of toxicity, mobility and volume
through treatment; long term effectiveness and permanence; state
and community acceptance.


11.0    DOCUMENTATION  OF  SIGNIFICANT CHANGES

Significant changes from the Proposed Plan must be documented in
accordance with CERCLA section 117(b).  Although the changes from
the originally proposed remedial alternative are significant they
could have been reasonably anticipated by the public based on the
alternatives and other information available in the proposed plan
and the supporting analysis and information in the administrative

                                81

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record.  Therefore,  no additional  public  comment  on  the revised
remedial alternative will  be offered.

The  State of Alabama indicated  grave concern  about the on-site
treatment aspect  of  Alternative 6.   This  was  due  to  the density
of the population in close proximity to the on-site  treatment of
contaminated soils.   The Region evaluated the State's concerns
with great scrutiny  and agreed  that  the selection of Alternative
3 provided for  a  better balance between the preference for on-
site treatment, and  the concerns for the  overall  negative effect
on the community.  Alternative  3 has therefore been  selected as
±he  final remedial alternative  for the Redwing Site.

The  soil clean-up levels protective  of ground water  generated by
Redwing Carriers  Inc.,  in  the Draft  Feasibility Study Report and
subsequently put-forth in  the Proposed Plan,  were reviewed and
revised.  Redwing used the SUMMERS model  to generate the levels
and  one correction was necessary for each compound.  Redwing
incorrectly calculated the octanol/water  partitioning coefficient
.(Koc) because they used an equation  that  is specific to only
certain compounds.   EPA recalculated the  soil clean-up levels
using compound  specific Koc values from the EPA publication
entitled Basics of Pump-and-Treat  Ground  Water Remediation
'Technology.  Table 18  reflects the  results of these
calculations.

Redwing did not use  a site specific  partitioning  coefficient to
determine the soil cleanup level for lead.  It was determined
that site specific values  should be  used.  EPA performed a
statistical analysis of site specific soil/water  partitioning
coefficients (Kd's)  generated for  the site rather than use the Kd
that was used before.   The cleanup level  which was obtained for
lead using this site specific Kd can been specified  as an action
level for further characterization of soil and groundwater in
areas where cleanup  levels for  other constituents of concern have
not  been exceeded.

Although some of  the cleanup levels  contained in  the Draft
Feasibility Study were computed incorrectly they  were calculated
to achieve the  remediation goals which would  result  in acceptable
exposure levels that are protective  of human  health  and the
environment.  The result of EPA's  recalculation of the cleanup
levels was that some of the levels became higher  while others
became lower, however,  the final remediation  goal remains the
same.  In the case of the  subsurface soil cleanup levels,
protection of the qroundwater AB a potential  drinking water
source is the final  remediation goal.   A comparison of the
cleanup levels  from  the Draft Feasibility Study and  EPA's
recalculated values, is presented  below:
                                82

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SOIL CLEAN-UP LEVELS PROTECTIVE OF GROUND WATER
   (all  cleanup  levels  are in units  of ug/ka)
Compound
DDT
Acetone
Aldrin
A-BHC
Chloroform
Chromium
Dieldrin
G-BHC (Lindane)
Methylene Chloride
Nickel
Vanadium
Vernolate
Proposed Plan
Cleanup Level
131
295
0.860
0.402
419
85,800
0.0959
9.40
9.05
30,300
157,000'
56.0
ROD Cleanup
Level
566
36
4
0.5
70
47,000
0.1
3.2
0.6
30,000
156,000
55.0
                       83

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APPENDIX B:CONCURRENCE LETTERS
              XIV

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                   IVL
Leigh Pegues. Director


1751 Cong.W.L.
Dickinson Drive
Montgomery. AL
36130
(205)271-7700
FAX 271-7950
   270-5612
Field Offices.


110 Vulcan Road
Birmingham. AL
3S209
(205)942-6166
FAX 941-1603


P.O. Box 9S3
Oecatur, AL
35602
(205)353-1713
FAX 340-9359


2204 Perimeter Road
Mobile. AL
3661S
(205)450-3400
FAX 479-2593
                                    ALABAMA
               DEPARTMENT OF ENVIRONMENTAL MANAGEMENT
                                                      Guy Hunt
                                                      Governor
                   November 30,
Mr. Kenneth  A.  Lucas,  RPM
U.S. EPA,  SSRB
345 Courtland St.  N.E.
Atlanta, GA  30365

Re:  Redwing Carriers/Sarland Apartments NPL Site
     Record  of  Decision

Dear Mr. Lucas:

    The  Alabama  Department of  Environmental Management
(ADEM),  Special  Projects,  received  the  second  draft
Record    of    Decision    (ROD)     for    the    Redwing
Carriers/Saraland  Apartments  NPL  Site  on  November 6,
1992, for  review and requested concurrence.

    This  office  appreciates the  EPA's consideration of
STATE concerns  expressed in correspondence and at our
September  -29,   1992  meeting,  with  you  and Mr.  Arthur
Collins, here in Montgomery.

    The   STATE   concurs    with   this    ROD,   but   has
reservations that  the  selected  remedy could be onerous
to   implement.    We   reiterate   the   position   that
protection of  human health  and the  environment  could
be  accomplished with  a  less  extensive  and disruptive
alternative.

    Confirmation of  the  presence or  absence  of source
material  beneath  buildings can  be ascertained by use
of  recently developed  sensing  equipment  used in the
oil industry and discussed with you.

    It   is   suggested   that  the   clean-up   level  for
Methylene  Chloride  in  subsurface  soil and  surficial
groundwater  may be at  or below detection limits.

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Page 2
Mr. Kenneth A. Lucas
November 30, 1992
    In  Section  7.3.  page  63.  2nd paragraph,  thermal
pre-treatment  of  source  material  and groundwater  is
not understood.   We  see similar  language  in  the draft
Scope of  Work,  received Wednesday, November  25,  1992.
Applicable air emission standards would have  to be met
in the use of any thermal device.

    Section  9.0 B..  page  80.  Groundwater  Remediation.
calls for discharge  of treated  water  to  be discharged
to the POTW  or to a nearby  surface waterbody.  Except
for  rain  events,  the  closest  waterbody  is  Norton
Creek,  1/2 mile from the site.

    Please  be  advised  that  concurrence  with  this  ROD
does  not bind  the  STATE   contractually  to  matching
requirements  in  the  event  of  Fund .Lead  remediation.
If  this  Lead  is  followed,   the  department  would
approach the  Legislature  to request funds  to meet the
fiscal matching requirements concerning this Site.

    If  there  are  questions,   call   this   office  at
(205)260-2787 or 260-2786.
                          Dahle^L E. Cooper,
                          Special Projects
/JEM/jdb

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