%EPA
            United States
            Environmental Protection
            Agency
              Office of
              Emergency and
              Remedial Response
EPA/ROD/R06-88/040
September 1988
Superfund
Record  of Decision:
                                           1
                                           i
            Sol Lynn/ Indutrial Transformers,TX

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REPORT DOCUMENTATION i- «EP°«T NO. 2.
pAQE EP A/ROD/ RO 6 -8 8/0 40
4. Title and Subtitle
SUPERFUND RECORD OF DECISION
1 First Remedial Action - Final
^k Author(s)
1 9. Performing Organization Name and Address

12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, S.W.

3. Recipient's Accession No.
5. Report Oat. Q9/23/BQ
6.
8. Performing Organization Rept. No
10. Project/Task/Work Unit No.
11. Contract(C) or Grant(G) No.
(C)

13. Type of Report & Period Covered
800/000
14.
 IS. Supplementary Notes
 16. Abstract (Limit: 200 words.)     ,    ,            j    .  ,       c-                     ^  -,  •
    Trie Sol  Lynn  site, also known  as  Industrial  Transformers  site,  is located  in Houston,
  Texas.   The  area around the three-quarter-acre site is a mix  of residential, commercial,
  and  light, industrial facilities.  Approximately 2,000 residents and 100,000  other  people
  move within  a  one-mile radius of the site on a daily basis  due to recreational
  activities associated with the area.  The site operated as  an electrical transformer
  salvage  and  recycling company between 1971 and 1978, and as a chemical recycling and
  supply company  from 1979 through 1980.  The first documented  investigation of this site
   ook place during the fall of 1971  when the City of Houston Water Pollution  Control
   ivision noted  that workers at Industrial Transformers poured oil out of electrical
  transformers onto the ground during transformer dismantling.   In 1981, strong odors
  originating  from the site were brought to the attention of  the Texas Department of Water
  Resources, the  predecessor agency of the Texas Water Commission (TWC).  Upon inspection,
  approximately 75 drums were found scattered about the property.  Most of the drums,
  labeled  "trichloroethylene", were empty and had puncture holes.  A technical assessment
  of the site, commencing in January  1986, indicated the presence of PCB contamination.
  PCB  contamination has been confined to the top two feet of  soil.  The highest
  concentrations  of PCBs were found in the middle of the site.   TCE has migrated deeper
   (See Attached Sheet)
  Sol  Lynn/Industrial Transformer,  TX
  First  Remedial Action - Final
  Contaminated Media:  gw
  Key  Contaminants:  TCE
   b. Identlfien/Open-Ended Terms

   c. COSATI Field/Group
   Availability Statement
19. Security Class (This Report)
    None
                                                        20. Security Class (This Page)
                                                            None
21. No. of Pages
    50
                                                                                  22. Price
(See ANSI-Z39.18)
                                        See Instruct/on* on Reverse
                         OPTIONAL FORM 272 (4-77
                         (Formerly NTIS-35)
                         Department of Commerce

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EPA/ROD/R06-83/040
Sol Lynn/Industrial Transformers, TX
Second Remedial Action - Final

16.  ABSTRACT (continued)

than the P'^Bs and away from the site.   Residual TCE remaining in the surface soil will
be remediated along with the PCB contaminated soils.  Any TCE that has migrated into th-
deeper ground water will be addressed in the second operable unit.  The primary
contaminants of concern affecting the soil are PCBs.

  The selected remedial action for this site includes:  excavation of approximately
2,400 yd-3 of PCB-contamir^ted soil and treatment using alkali metal polyethylene
glycolate (APEG) complex dechlorination with onsite disposal of treatment residuals;
effectiveness verification of the dechlorination process through treatability studies;
and pretreatment of liquid by-pro<.".ucts, if necessary, with discharge into a publicly
owned treatment works facility.  The estimated present worth cost for this remedial
action is 52,200,000.

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     RECORD OF DECISON
            FOR
INDUSTRIAL TRANSFORMER SITE
          PHASE II
          Houston
    Harris County, Texas
       September 1988

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                            TABLE OF CONTENTS


I.  Declaration by Regional  Administrator

II.  Decision Summary

    A.   Site Location and Description 	 1

        Site History

        Geology

        Remedial  Investigation Results

        Potential  Impacts of the Site on
          Human Health and the Environment

    B.   Enforcement  	  9

    C.   Community  Relations  History 	  9

    D.   Evaluation 	 10

        Evaluation Criteria

        Description of Alternatives

    E.   Recommended Remedy  	 22



III. Attachments

     A. Administrative Record Index

     B. Community  Relations  and Responsiveness Summary

     C.  TWC Letter of Agreement

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                             LIST OF FIGURES


Figure                                                         Page

 1                  Site Location                               2

 2                  Location of Shallow Monitoring Wells
                           and Sample Concentration             5

 3                  Plume Outline in Shallow Zone               6

 4                  Location of Second Zone Monitoring Wells    8
                      and Sample Concentrations

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                              LIST OF TABLES


TABLE                                                      PAGE

 1                   Evaluation of Alternatives             17

 2                   Applicable or Relevant and             18
                     Appropriate Federal and
                     State Laws

 3                   Cost                                   21

 4                   Sensitivity Analysis                   23

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                             DECLARATION OF
                            RECORD OF DECISION
SITE NAME AND LOCATION

Industrial Transformers Site
Houston, Texas

STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected remedial action for the
Industrial Transformers site in Houston, Texas, developed in accordance
with the Comprehensive Environmental Response, Compensation and Liability
Act of 1980 (CERCLA) as amended by the Superfund Amendments and Reauthorization
Act of 1986 (SARA), and the National Contingency Plan (40 CFR Part 300).
This decision is based on the administrative record for this site.  The
attached index identifies the items which comprise the administrative record
upon which the selection of the remedial action is based.
DESCRIPTION OF THE REMEDY

This operable unit is the final action of two operable units for the
site.  This operable unit addresses the groundwater contamination.  The
remedy addresses the principal threat at the site by treating the
contaminated groundwater and reducing the risks associated with exposure
to the contaminated water.  The first operable unit at this site involves
remediation of the contaminated soil.

The major components of the selected groundwater remedy include:

-- Pump and treat, via air stripping, approximately 12 million gallons of
   groundwater which exceeds the primary drinking water standard for TCE.

— A carbon unit will be used to filter the exhaust air if it does not
   meet Texas Air Quality Criteria.

— The treated groundwater will be disposed in a sanitary sewer or pumped
   back into the waterbearing zone.

DECLARATION

The selected remedy is protective of human health and the environment,
attains Federal  and State requirements that are applicable, or relevant
and appropriate  to the remedial action, and is cost-effective.  This remedy
satisfies the statutory preference for remedies that employ treatment
that reduces toxicity, mobility or volume as a principal  element and
utilizes permanent solutions and alternative treatment (or resource

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recovery) technologies to the maximum extent'practicable.  Because this
remedy will not result in hazardous substances remaining onsite above
health-based levels, the five year facility review will  not apply to this
action.

The State of Texas has been consulted and supports this  remedial decision.
Date             '                                  Robert E. Layton Jr.P.E.
                                                    Regional  Administrator

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             Summary of Remedial Alternatives Selection for the
                   Sol Lynn/Industrial Transformer Site,
                      Operable Unit II, Houston, Texas


 SITE LOCATION AND DESCRIPTION

 The Sol  Lynn Superfund site, which is approximately three quarters of an
 acre in  size, (also known as Industrial  Transformers (IT)) is located in
 Houston, Texas.  As shown in Figure 1, the site is located just south of
 1-610 and west of Highway 288.  There are two buildings on site which
 house four retail businesses.  The area  around the site is a mix of
 residential, commercial  and light industrial facilities.  The light
 industrial and commercial business areas are located directly to the east
 and south of the site.   Astroworld and  Astrodome are approximately 3,000
 feet to  the northwest of the site and a  mix of private, single and multi-
 family dwellings are approximately 4,000 feet to the north.  The residential
 population 'in the area is about 2,000 and a maximum daily traffic of
 100,000  persons may move within a one mile radius due to recreational
 activities associated with the Astrodome and Astroworld.

 Surface  drainage around  the site include shallow ditches that border the
 site along Knight and Mansard Streets.  These two ditches carry surface
 runoff by slightly different routes to Braes Bayou, which empties into
 Buffalo  Bayou then into  the San Jacinto  River.  The San Jacinto River
 ultimately flows into Galveston Bay.   The site is above the 100-year
 flood plain.

 SITE HISTORY

 The Industrial  Transformer site is the location of a former electrical
 transformer salvage and  recycler company which operated between 1971 and
 1978. A chemical recycling and supply company subsequently operated at
 the same location from 1979 through 1980.

 The first documented investigation of this site took place during the fall
 of 1971  when the City of Houston Water Pollution Control Division noted
 that workers at the Industrial  Transformer Company poured oil out of
 electrical transformers  onto the ground  as they were being dismantled.
 In 1981, strong odors originating from the site were brought to the
 attention of the Texas Department of  Water Resources, the predecessor
 agency of the Texas Water Commission  (TWC).  Upon inspection it was
 revealed that approximately 75 drums  were scattered about the property.
 Most of  the drums, labeled "trichloroethylene", were empty and had puncture
.,noles.

 In October 1984 the site was proposed for inclusion on the National
 Priorities List.  In September 1985,  the TWC entered into a Cooperative
 Agreement with  the Environmental Protection Agency (EPA) to conduct the

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          FIGURE  1
INDUSTRIAL TRANSFORMERS SITE

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 Remedial  Investigation/Feasibility  Study  (RI/FS)  at  the  site.   Utilizing
 funds  from  this  cooperative  agreement,  the  TWC  contracted  with  Radian
 Corporation on  June  30,  1986,  for a technical assessment of  the site.

 In  an  effort  to  address  the  contamination in  an expeditious  manner,  the
 site was  broken  down  into  parts  called  operable units.   The  first  operable
 unit addressed  soil  contamination in  the  Phase  I  remedial  investigation
 and feasibility  study.   The  results of  this  investigation  indicated  poly-
 chlorinated biphenols (PCBs) are isolated in  the  upper two feet of soil
 at  concentrations  to  350 ppm.  Trichloroethene  (TCE)  was also found  in
 the soil  in concentrations below the  health  criterion of 160 ppm.   Chemical
 Dechlorinization was  selected  as the  soil remedy.  The remedy selection
 is  documented in the  Record  of Decision dated March  25,  1988.

 This summary  only  examines potential  remedial alternatives'for  the ground-
 water  operable  unit,  Phase II.

 GEOLOGY

 Surface soils at the  site  and  in the  vicinity are  of  the Lake Charles
 series.   These  soils  are characterized  by somewhat poor  drainage and high
 available water  capacity.  When  the soil  is  dry,  deep, wide  cracks form
 on  the surface where  water can enter  rapidly.  When  the  soil is wet  the
 cracks are  sealed  and water  infiltrates slowly.

 Below  the surface  soil  is  Beaumont  Clay, which  is  of  Pleistocene age.
 The lithology of the  Beaumont  Clay  is comprised of unconsolidated  clays
 and muds  or deposits  of  clayey sands  and silts.   The  clays and  muds  were
 deposited as  interdistributary,  abandoned channel  fill,  overbank fluvial
 or  mud-filled coastal  lake or  tidal  creek muds.   The  sands and  silts
 represent alluvium,  levee  and  crevasse  splays.

 The uppermost aquifer is encountered  at a depth of 30-34 feet below  ground
 surface.  This particular  aquifer is  a water-bearing  sand  that  varies in
 thickness from 2 feet to 6 feet, averaging  4  and  1/2  feet.   Sand content
 increases from west to east  across  the  site,  from  50  percent to 70 percent.
 Water  levels  taken at monitoring wells  in uppermost  zone indicate  that the
 groundwater flows  to  the northwest.

 The uppermost water-bearing  sand is separated from the next  lower, or
 "second", water-bearing  sand by  a stiff clay, approximately  45  to  52 feet
 thick.  The second water-bearing sand is underlain by clay.  Water levels
^taken  at  monitoring wells  in the second zone  indicate that the  groundwater
"-flows  to  the  west.

 These  aquifers are not used  as drinking water supplies.  However,  these
 aquifers  have the  potential  to be drinking water  sources,  Therefore, they
 are Class IIB aquifers in  the  EPA groundwater classification system.

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'The major  aquifers  in the  Houston area are the Chicot and Evangeline.
 These  aquifers  supplement  surface water  in supplying the City with drinking
 water.   In  the  vicinity  of the  site the  shallowest well for the City of
 Houston  is  screened  at 670 feet below the surface.

 REMEDIAL INVESTIGATION RESULTS

 During the  Remedial  Investigation (RI) groundwater samples were collected
 using  monitoring wells  and cone penetrameter to determine the nature and
 extent of  contamination  in the  groundwater.  Soil samples were also
 collected  as the monitoring wells were installed.

 Because  information  collected previously by TWC indicated the primary
 contaminants at the  site were polychlorinated biphenyls (PCBs) and
 trichloroethylene (TCE), the emphasis for analytical testing was  placed
 on determining  the  vertical and areal extent of these contaminants.  PCBs
 were known  to adsorb tightly to soils and were not expected to infiltrate
 into the groundwater.  The phase I remedial investigation results verified
 this,  as PCBs were  only  found in the upper two feet of soil.  In  addition,
 the leaching of PCBs into  the groundwater would not be expected and
 accordingly, groundwater sampling did not show any PCB contamination.  On
 the other  hand, TCE  does not adhere tightly to the soils but will tend to
 migrate  through the  soil.  TCE  is also quite soluble in water.  This
 indicates  that  the  potential for TCE to  leach into groundwater is high.
 Groundwater sampling results indicate that this is the case.

 The groundwater was  sampled by  two different methods.  The first  method
 involved withdrawing water samples from  installed monitoring wells.  Water
 samples  were collected twice from six monitoring wells screened in the
 uppermost  water-bearing  zone and analyzed for TCE.  The locations of
 the wells  and TCE concentrations for both sampling events are shown on
 Figure 2.

 In the second method, a  cone penetrometer was advanced into the uppermost
 water-bearing sand.  A well-screen tip was substituted for the tip of the
 cone penetrometer and at a selected depth the sampling sleeve was pulled
 up to  expose the screen.  Twenty samples were obtained and analyzed for
 TCE from this method.  The cone penetrometer was only used in the upper-
 most aquifer.

 The results from both methods indicate the highest concentration  of TCE
 in the groundwater  Is directly  below the island between the South Loop West
 feeder street and South  Loop West.

 Figure 3 shows  contour lines of TCE in the uppermost water-bearing zone
 using  both  the  monitoring  well  water samples and the cone penetrometer
 samples.  This  illustration indicates the plume extends to the north-
 northwest.

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                                    7

Three monitoring wells which were installed in the second water-bearing zone,
were sampled twice.  The concentrations of TCE from both sampling events
and the location of the wells are illustrated in Figure 4.  Although
these three wells cannot identify the extent of the plume or the volume
of contaminated water in this zone they do indicate: (a) that the TCE has
penetrated down to this water-bearing zone; and (b) that the flow gradient
of this zone is to the west.

Deep soil  samples were taken during the installation of monitoring well
#10.  These samples were taken at two-foot intervals.  The analytical
results indicate that TCE contamination was found as deep as 101 feet.
The highest concentration of TCE in the soil was 600 ppm obtained in a
sample taken at a depth of 18-20 feet.  Based on laboratory studies, soil
above the water table will  contribute TCE to the groundwater by two
mechanisms.  First, as groundwater is pumped from the upper water-bearing zone,
water in the soil above the water table will be drawn into the aquifer.
TCE in the soil will  be released in the water-bearing zone as the ground-
water is pumped.  Second, TCE will also reach the water table as rainwater
percolates through the soil.  Because it is quite soluble and will not
tend to adsorb to the soil  particles of the aquifer, TCE is expected to
be quite mobile once it reaches the groundwater, increasing the size of
the plume.

The general water quality was also determined in this investigation.  The
analytical results revealed that there are up to 3670 mg/1 of dissolved
solids in the upper aquifer and up to 1650 mg/1 In the second aquifer.
Suspended solids are visually noted in both aquifers.  While the suspended
and dissolved solids are high in both aquifers they are still within the
potential  drinking water range.  The EPA identifies a potential drinking
water source as having less than 10,000 mg/1 dissolved solids.  These
aquifers could be classified as Class IIB aquifers.  They are not currently
used as a resource, but could be used as a future supplemental source of
water.

These observations indicate the following:

     o  TCE contamination is observed in the soil  on site from the surface
        to a depth of 101 feet;

     o  TCE contaminates both the uppermost and the second water-bearing
        zones.  The highest concentrations of TCE (790 ppm; cone penetrometer
        number 13) in the uppermost aquifer was observed off site underneath
        the median strip between 1-610 South Loop West and the southern
        feeder street.   The volume of contaminated water in the uppermost
        aquifer is estimated at 3.2 million gallons;

     o  Although a volume cannot be defined for the second water-bearing
        zone because of the westerly gradient; it appears the Phase II
        investigation has identified the northern boundary of the plume.
        Further definition of the plume will be required in the remedial
        design portion of this project.

    o  TCE is the only identfied contaminant in the groundwater.

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      Potential  Impacts of the Site on Human Health and the Environment

      As part of the remedial  investigation, an assessment  of the  health threat
      created by the current site conditions was conducted.  Factors  included
      in this risk assessment  were the identified target receptors,  the maximum
      concentrations of TCE, and the degree of exposure to  the hazards from the
      site.  Target receptors  identified in the assessment  included  anyone who
      utilizes or comes in contact with the contaminated groundwater.

      The results of the risk  assessment indicate that the  highest concentration
      of TCE found in the groundwater presents greater than a 10"^  (one in ten)
      lifetime cancer risk.   This level  represents the threat that would be
      posed by the site conditions if no remedy were implemented and  the groundwater
      utilized.   This assessment assumes a 70 kg person consumes 2  liters of
      contaminated water each  day.  The major pathways of exposure are inhalation
      and ingestion.

      Levels of  cleanup are  based on a comparison of the contaminant  concentration
      found at the site to either 1) existing health based  standards  or criteria;
      or 2) concentrations that would represent a 10   to 10   lifetime cancer
      risk.  Because a standard exists,  it is not necessary to calculate a
      concentration representing the risk range.  The health-based criterion
      for TCE in contaminated  water is .005 mg/1 (Safe Drinking Water  Act of
      December 1974 as amended in 1986).

 II.   ENFORCEMENT

      The goal  of the EPA is to have those parties responsible for contamination
      of the site perform the  cleanup.  There are two identified potentially
      responsible parties (PRPs) for the IT site.  These parties will  be given
      the opportunity to conduct or participate in the remedial action selected
      for the site.  If they refuse, EPA may order the parties to  perform the
      remedial  design and if they continue to refuse, proceed against  them
      for cost recovery after  EPA has funded and implemented the proposed remedy.

III.   COMMUNITY  RELATIONS HISTORY

      The Industrial  Transformer Superfund site was proposed for the  National
      Priorities List (NPL)  in October 1984.  In February 1985 the U.S.
      Environmental  Protection Agency (EPA) and the Texas Water Commission
      (TWC) held a public meeting in Houston for residents  near the  site to
      discuss site conditions  and the Superfund Program/Process.  Approximately
      15 people  attended the meeting.  On October 3, 1985,  EPA issued  a news
      release announcing that  funds to study the site had been awarded to the
      TWC.

      Initiation of studies  on the Industrial  Transformer site was announced by
      TWC at a public meeting  in Houston on September 24, 1986.  Evaluation of
      the site was divided into two separate studies:  1) surface soil  contamination;
      2) groundwater contamination.  The study addressing surface soil  contamination

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IV.
                                    10

was completed in December 1987.  On January 21, 1988, EPA announced to
the public via a news release that a public meeting would be held on
February 2, 1988, to discuss the proposed remedy for surface contamination
at the site.

An EPA prepared fact sheet which described alternative remedial actions
for the soil contamination along with the EPA preferred alternative was
sent to the interested and affected public shortly after the public
meeting was announced.  EPA and TWC conducted the 7:00 p.m. public meeting
at the Astro Village Hotel on February 2, 1988.  Approximately 35 people
attended the public meeting.

On August 8, 1988, a news release announced that a public comment period
on the groundwater study would begin on August 10, 1988, and end on
September 9, 1988.  The news release also announced that a public meeting
would be held on August 25, 1988, at the Astro Village Hotel, Houston, Texas

An EPA prepared fact sheet describing the alternative remedial actions for
the groundwater study along with the EPA preferred alternative was sent
to the site mailing list shortly after the meeting and comment period was
announced.  EPA and TWC conducted the 7:00 p.m. public meeting on August 25,
1988.  Approximately 15 people attended the meeting.  Only two
questions were asked and no comments were made during the public meeting.

Further details on community relations are contained in Attachment B.

EVALUATION
 A.  Evaluation Criteria

     1.  SARA Requirements - Section 121(a) through (f) of SARA contains three
         factors which EPA must consider in selecting a remedy.

         a.  Protection of Human Health and the Environment

             The alternative must provide adequate protection of human health
             and the environment.

         b.  Cost Effectiveness

             Cost effectiveness includes an evaluation of the following criteria:

             i.  Long-term Effectiveness and Permanence

                 Alternatives are assessed for the long-term effectiveness and
                 permanence they afford along with the degree of certainty that
                 the remedy will prove successful.  Factors considered are:

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                              11

      •  magnitude of residual  risks in terms of amounts and concen-
         trations of waste remaining following implementation of a
         remedial action, considering the persistence, toxicity,
         mobility, and propensity to bioaccumulate of such hazardous
         substances and their constituents;

      •  type and degree of long-term management required, including
         monitoring and operation maintenance;

      •  long-term reliability  of the engineering and institutional
         controls, including uncertainties associated with land
         disposal of untreated  wastes and residuals.

 ii .   Short-term Effectiveness

      The short-term effectiveness of alternatives must be assessed
      considering appropriate factors among the following:

      0  magnitude of reduction of existing risks;

      •  short-term risks that  might be posed to the  community,
         workers, or the environment during implementation of an
         alternative including  potential  threats to human health
         and the environment associated with evacuation, trans-
         portation, and redisposal or containment;

      0  time until full  protection is achieved;

      •  potential need for replacement remedy;

      •  potential for exposure of human  and the environmental
         receptors for remaining waste considering the potential
         threat to human health and the environment associated
         with excavation, transportation, redisposal  or containment.

iii.   Implementability

      The ease or difficulty of implementing the alternatives are
      assessed by considering the following types of  factors:

      •  degree of difficulty associated  with constructing the
         technology;

      •  expected operational reliability of the technology;

      •  need to coordinate with and obtain necessary approvals and
         permits (e.g. NPDES, Dredge and  Fill  Permits for off-site
         actions) from other offices and  agencies;

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                                    12

            •  availability  of necessary  equipment  and  specialists;

            0  available  capacity  and  location  of  needed  treatment,
               storage,  and  disposal  services;

            •  compatibility with  existing  future  land  use;

            •  need  to  respond to  other  sites.

       iv.   Cost

            The types  of  costs that  should  be  assessed  include  the  following:

            t  capital  cost;

            •  operational  and maintenance  costs;

            •  cost  of  five-year reviews, where required;

            •  net  present  value of  capital  and O&M costs;

            •  potential  future remedial  action costs.

    c.   Compliance  with Applicable or  Relevant  and  Appropriate  Federal
        and State Regulations

        In  determining  appropriate remedial  actions at  Superfund  sites,
        consideration  must  be given  to  the  requirements of  other  Federal
        and State laws.   Alternatives  should be assessed  as  to  whether
        they attain  legally applicable  or  relevant  and  appropriate  require-
        ments of other  Federal and State  public health  environmental  laws.
        Requirements under  Federal and  State laws  that  specifically address
        the circumstances at a Superfund  site  are  considered applicable.
        Relevant and appropriate requirements,  while not  applicable to  a
        Superfund site, address situations  which are sufficiently similar
        to  those existing at the site.

2.  SARA Preferences.   The  EPA is  also  directed by  SARA to  give preference
    to remedial actions which reduce the  toxicity,  mobility  or  volume of  the
    waste.   Relevant factors are:

            •  the  treatment processes  the  remedies employ  and  materials
               they will  treat;

            •  the  amount of hazardous  material that will  be destroyed
               or treated;

            •  the  degree of expected  reduction in  toxicity, mobility,  or
               volume;

            •  the  degree to which the treatment is irreversible;

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                                        13

                •  the residuals that will remain following treatment, considering
                   the persistence, toxicity,  mobility,  and propensity for
                   bioaccumulation of such hazardous substances and their
                   constituents.

    3.  EPA Guioelines.  It is EPA policy to consider other factors in selection
        of a remedy.These include:

        a.  Community Reaction

            This assessment should look at:

            •  components of the alternatives  which the  community supports;

            •  features of the alternatives about which  the community has
               reservations;

            •  elements of the alternatives which the community strongly
               opposes.

        b.  State Acceptance

            Evaluation factors include assessments of:

            •  components of the alternatives  the State  supports;

            •  features of the alternatives about which  the State has
               reservations;

            •  elements of the alternatives- under consideration that the
               State  strongly opposes.

B.  Description of Alternatives

    In accordance with the NCR, an initial set of remedial  approaches were
    screened to determine whether they might be appropriate for this site.
    From these possible remedies, five remedial  alternatives were chosen for
    more detailed evaluation and comparison with the remedy selection criteria
    outlined above.  Two discharge alternatives are also identified.

    All  the action alternatives include pumping the contaminated groundwater
    to the surface.  The recovery system consists of placing a number of
    wells on and around the site and extracting the groundwater.  For cost
    estimating purposes it was assumed that ten wells would be installed 30
    feet deep.  These wells would pump a total of 3500 gallons per day.   The
    recovery system will extract the 3.2 million gallons of contaminated
    groundwater currently estimated at the site.  An additional volume of
    groundwater will  be pumped and treated as  TCE is released from the soil
    particles in the  water-bearing zones.  Water percolating through the

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                                    14

unsaturated zone will also add to the total volume of groundwater to be
treated.  The total volume may approach 12 million gallons of water from
the upper waterbearing zone.  This recovery system will  require approximately^
10 years to remove 12 million gallons of water.

Alternative 1, No Action - No additional remedial actions would be conducted.
The selected soil remedy would be conducted without treatment of the con-
taminated groundwater.  However, annual environmental monitoring would be
required to assess the horizontal and vertical migration of the TCE.  In
addition, a review to occur every five years would be budgeted into
the total costs.  A five year review is necessary on any site if wastes
above health-based levels remain at the site.  The present worth of this
alternative is estimated to be $400,000.

Alternative 2 - Collection and Off site Deep Well Injection - This alternative
requires that the contaminated groundwater would be pumped and stored in
tanks on site.  The water would then be shipped via a vacuum tank truck
to a deep well injection facility in compliance with EPA regulations.

The deep well facility would provide injection, isolation and monitoring
of the contaminated water.  Generally, these facilities  will use deep
clay and shale formations to confine the waste.  In the  Gulf Coast region,
the injection depths for these wells typically range from 7,000 to 8,000
feet.

The site would be monitored during and after remediation for evaluation
of the effectiveness of the alternative.

This alternative is not a treatment alternative and therefore does not
destroy the TCE.  Deep well injection would provide measures for permanent
isolation and containment of the contaminated groundwater.  This alternative
is estimated to cost $4.8 million.

Alternative 3 - Collection, On site Carbon Adsorption and Discharge - In
this alternative the contaminated water would be pumped, as previously
described, to a storage tank where the solids would be settled.  From
this settling tank the water would be piped to a carbon  adsorption system.

The most applicable carbon adsorption unit is the downflow fixed dual
bed granular activated carbon adsorption system.  Water  would flow, by
gravity, down through the column and the TCE would bind  to adsorption
sites on the activated carbon.  Once the adsorption sites became filled
with contaminants, the carbon will need to be replaced or regenerated.

The treated water will be tested.  If the TCE levels are below the discharge
criterion, the water will be discharged using one of the options discussed
below.   If the concentrations are above the criterion, the water will run
through the secondary carbon bed for polishing.

-------
                                    15

The spent carbon from the adsorption would be shipped off site for regener-
ation or disposal.  The settled solids in the settling tank will be
periodically cleaned out and analyzed for TCE.  If the solids do not contain
TCE they will be shipped off site.  If they do contain TCE they will be
air stripped and then shipped off site.

This alternative will require a treatability study to select the carbon
and design the system.  However, this is a routine study and easily done.

This alternative does not destroy TCE, however, it does reduce the volume
of TCE contaminated material and would remove the contaminants from the
groundwater, concentrating them on the activated carbon which would be
disposed in accordance with appropriate regulations.  This alternative is
estimated to cost $1.8 million.

Alternative 4 - Collection, On site Air Stripping and Discharge - In
this alternative the recovery wells will discharge into settling tanks.
The water would then be pumped to an air stripping system.

The counter-current packed tower configuration has been chosen for its
effectiveness and adaptability.  Air stripping works by pushing air
through the contaminated water forcing the volatile chemical contaminants
such as TCE to mix with the air and evaporate.

As with Alternative 3, the treated water will be sampled.  If it meets
the established criterion it will be discharged, if not it will be run
through the system again.

The air emissions will be monitored to ensure that there is no threat to
human health and the environment.  If the air meets all emission standards
it will be released into the atmosphere.  If it does not meet the emission
standards an activated carbon unit will be added to the air stripper.  This
will be determined during the design portion of the site remediation.

A treatability study will be required to provide design parameters for
the air stripping tower.  However, this is a routine study and easily
performed.

This alternative does not destroy TCE but will remove it from the water
and concentrate it on activated carbon.  The TCE may be destroyed during
the disposal or regeneration of the carbon.  The present worth of this
alternative is estimated at $2.2 million.

Alternative 5 - Collection, On site Catalytic Dehydrochlorination and Discharge

As with the previous two alternatives, the water is withdrawn and stored in a
settling tank.

-------
                                    16

The contaminated water will be pumped into a batch dehydrochlorination
reactor.  This alternative will destroy the TCE through a chemical  reaction,
removing the chlorine atoms from the TCE molecule.  The residuals from
this reaction would include off-gas and brine, both of which could  require
additional treatment or disposal.  A carbon adsorption column will  be
used for the treatment of the gases.  The brine will  be stored and  shipped
off-site for disposal  via deep well injection.

A treatability study would be performed prior to implementation of  this
alternative to determine reactor size, flow rate and other design parameters,
The estimated present worth of this alternative is $6.3 million.

After the cleanup criteria are met, two discharge options will be considered
for Alternatives 3,4, and 5.  These are (a) reinjection and (b) discharging
into publicly owned treatment works (POTW).  Reinjection involves pumping
the treated water back into the water bearing zone.  This option may
increase the recovery rate of the contaminated water.  Discharging  into a
treatment plant would require obtaining permission from the City of
Houston Public Works Department and TWC before releasing the treated
water into the wastewater system.  This option would also require that
the standards of the National Pollution Discharge Elimination System
(NPDES) be met.  Reinjection is estimated to cost $93,650 and discharging
into a POTW is estimated to cost $212,860.

Evaluation of Alternatives

An evaluation of the alternatives is shown on Table 1.  The following
values were assigned to compare remedial selection criteria:

+  Alternative would exceed a criterion in comparison to other alternatives.

0  Alternative can be designed to meet the selection criterion.

-  In comparison to other remedies, this alternative will present difficulty
   in achieving a selection criterion.

1.  Complies with ARARs - (meets or exceeds Applicable, or Relevant and
    Appropriate Federal and State Requirements.)  Table 2 delineates the
    Federal and State statutes which are applicable or relevant and
    appropriate (ARARs).  In all instances where the regulation is
    considered applicable or relevant and appropriate, those requirements
    will be met.  The maximum contaminant level (MCL) for TCE is considered
    the appropriate cleanup criteria because these are considered Class
    IIB aquifers.
2.  Reduces Toxicity, Mobility and Volume - The "No Action" alternatives
    was rated  0  in reducing toxicity and mobility because it does nothing
    to reduce these parameters.  The volume will continue to increase as
    the plume spreads.  Therefore, it was rated "-" for volume reduction.
    Natural flushing will occur; however, due to the low transmissivity
    it will take generations as compared with a decade using any of the
    other alternative.  Deep well injection was rated "0" for toxicity

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                                    20

    and volume reduction because it does nothing to reduce these parameters.
    Deep well injection does reduce the mobility of waste, however, not
    as permanently as the three treatment alternatives; therefore, it
    rated a "0" for mobility reduction.  The three other alternatives all
    rated a "+" for toxicity, volume and mobility reduction because they
    removed the hazardous compound from the site and reduced the volume.
    In the ultimate disposal of the by-products the TCE may be destroyed
    (i.e., through the incineration of the carbon).

3.  Short Term Effectiveness - The "No action" was rated "-" in relation
    to all other treatment alternatives because of the relative differences
    in time between the natural flushing action of the aquifer versus the
    pumping associated with the other alternatives; however, since no one
    is using this aquifer it does not pose a short-term health risk.
    Deep well injection rated a "0" because it requires transporting the
    wastes off site which may pose a threat to the community or the
    environment during implementation of the alternative if a spill
    occurred.  The other pumping alternatives rated "+" because they pose
    little threat to the community and the environment and they return
    the aquifer to a potentially useable water source in a short time
    compared to the "No Action" alternative.

4.  Long Term Effectiveness - "No Action" does nothing to remediate the
    effect of the contamination on site; therefore, it was rated a "-".
    The action alternatives do alleviate the health threat and return
    the aquifer to useable water source.  Therefore, they all rated a "+".

5.  Implementability - The "No Action" and air stripping alternatives are.
  .  the most easily implementable alternatives, therefore, they rated a
    "+".  Deep well injection may be more difficult to implement because
    the possibility exists that a deep well injection facility may not be
    available to receive all of the fluid withdrawn over the life of the
    remedy.  For this reason deep well injection rated a "0".  Carbon
    adsorption is well proven and generally easily implemented.  However,
    the groundwater has an abundance of dissolved solids which may decrease
    the life of the carbon, therefore, it rated a "0".  Catalytic Dehydro-
    chlorination is an innovative technology and will require a more
    extensive treatability study than the other alternatives. Specialists
    will be needed to set up and run the treatability studies and teach
    the operators about the system, so it was also rated "0".
6.  Cost - Estimated costs for each remedial action alternative are
    summarized on Table 3.  Included in this table are capital
    costs, annual operations and maintenance cost, present worth of
    operation and maintenance cost and total present worth.

    Because the plume in the second water bearing zone is not defined, a
    sensitivity analysis was performed relating the volume of water to
    cost.  Scenario A assumes ten wells would be installed.  Each well
    would pump 350 gallons per day for ten years (12 million gallons).
    Scenario B assumes 50 wells will be installed, with each well pumping

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                                   22

    at a rate of 350 gallons/day over a ten year period (64 million
    gallons).  As the volume of water pumped increases, the cost per
    gallon decreases for carbon adsorption and air stripping.  Air
    stripping becomes the most cost effective.

    The results of the sensitivity analysis are summarized on
    Table 4.

7.  Community Reaction -  The public comment period began August 10, 1988,
    and ended September 10, 1988.  The meeting was held August 24.  Two
    comments were received during the public meeting and several throughout
    the comment period.  All the comments and the Agency's responses are
    provided in Attachment B.

8.  State Acceptance -  The State of Texas has been consulted and
    supports this remedy.

9.  Overall Protection of Human Health and the Environment - All pumping
    alternatives can potentially reduce groundwater contamination and
    thereby be protective of human health and the environment, therefore
    they rated a."+" while the "No Action" was rated a "-" because it
    does nothing to protect human health and the environment.

RECOMMENDED REMEDY:  Air Stripping

Treatability studies will be conducted during the design phase of the
project.  Additional hydrogeological studies will also be conducted during
the design stage to define the extent of the plume in the second water-
bearing zone.  The contaminated groundwater will be recovered and the
suspended solids allowed to settle.  The water will be pumped into a
packed air column, sprayed onto the packing coming in contact with the
air.  The TCE will evaporate as it comes in contact with the air.  The
air will be monitored as it is released out of the column.  If the released
air does not meet Texas Air Control Board air quality criteria, a carbon
adsorption unit will be added to the air stripping column.  After the
concentration of TCE in the water is reduced below .005 ppm, the water
will be discharged into the Houston sanitary sewer system or reinjected
into the water-bearing zones.

The groundwater will be sampled and analyzed while the remedy is in
operation.  EPA anticipates that the concentration of TCE in the
recovered groundwater will decrease over time.  Should the sampling
results indicate that the concentration of TCE is not decreasing, the
feasibility of achieving the remedial criteria in a reasonable period
of time and the possibility of revising or terminating the remedial
action will be evaluated.

Rationale

As previously stated, based on the  information available to evaluate the
five remedial options against these nine criteria, the EPA has concluded
that Alternative 4, Air Stripping,  is the Agency's preferred alternative.

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                                 TABLE 4
                   SENSITIVITY ANALYSIS OF ALTERNATIVES
                           PRESENT WORTH COSTS
                                        SCENARIO
    ALTERNATIVE

1.  No Action

2.  Deep Well Injection

3.  Carbon Adsorption

4.  Air Stripping

5.  Catalytic Dehydro-
     chlorination
A
$411,248
$4,789,955
$1,885,424
$2,204,890
$6,332,267
B.
$411,248
$20,960,117
$3,951,900
$3,077,547
$14,001,398
                                    23

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                                    24
This alternative is more easily implemented than carbon adsorption
because of the dissolved solids in the aquifer.  There will  also be less
materials handling required for the air stripping alternative than the
carbon adsorption alternative.  This alternative is protective of human
health and the environment, attains all applicable or relevant and appropriate
Federal and State requirements and is cost-effective.  This  alternative
also satisfies SARA's preference for a remedy which employs  treatment as
the principal  element to reduce toxicity, mobility, or volume.

Operation and Maintenance (O&M)

The site will  be monitored during and after remediation for  evaluation of
effectiveness of the alternative.  The monitoring will be accomplished by
sampling the groundwater on a selected interval and analyzing for TCE to
determine if remediation is continuing as planned.

Future Actions

No future actions are anticipated for the groundwater.  The  selected remedial
action will  afford a high degree of permanence.

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                    Tentative Remedial Action Schedule


Approval Remedial Action (Sign ROD)                    September 1988

Complete Enforcement Negotiation                       Febuary 1989

Award Cooperative Agreement Amendment
  for Design of Approved Remedy                        September 1989

Start Design                                           September 1989

Complete Design                                        October 1990

Award Remedial  Cooperative                             November 1990
  Agreement Amendment for Construction
    of Approved Remedy

Start Construction                                     May 1991

Complete Remediation                                   July 2001

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ATTACHMENT A

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SITE NAMEi
SITE NUMBER.
ADMINISTRATIVE RECORD INDEX

         ADDENDUM

Sol Lynn Phase II
TXD 980873327
DOCUMENT NUMBER:
DOCUMENT DATEi
NUMBER OF PAGES:
AUTHOR•
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE.
DOCUMENT TITLE:
         123
     02/02/88
     001
     Arthur Talley
     Texas Water Commission
     Sherry Fuerst, U.S. EPA Region VI
     Record of Communication
     Acccess agreement for groundwater sample
     for Sol Lynn
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
         124
     03/30/88
     001
     Sharon E.  Fuerst, Regional Project Manager
     U.S.  EPA Region VI
     Robert Rountree, Texas Water Commission
     Correspondence
     Transmittal of EPA's final comments for the
     Industrial Transformer Remedial
     Investigation and Feasibility Study Reports
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:

COMPANY/AGENCY:
 .*

RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
         125
     04/04/88
     014
     Carl R. Hickam, R.S.,  Senior Regional
     Representative
     Agency for Toxic Substance and Disease
     Registry/ROHR-Region VI
     Carl Edlund,  Chief,  Superfund Program
     Branch
     Correspondence and Attachment
     Draft Health  Assessment for the Industrial
     Transformers  site; provides findings and
     recommendations regarding public health
     issues and or concerns for this site and
     adjacent areas
                            A-l

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SITE NAME:
SITE NUMBER:
ADMINISTRATIVE RECORD INDEX

         ADDENDUM

Sol Lynn Phase II
TXD 980873327
DOCUMENT NUMBER:
DOCUMENT DATE.
NUMBER OF PAGES:
AUTHORt

COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
         126
     04/06/88
     001
     Robin Gelston-Walls,  Texas State
     Coordinator, State Programs Section
     U.S. EPA Region VI
     David H. Sorrells, Texas Water Commission
     Correspondence w/o referenced enclosures
     Transmittal of signed copies of Record of
     Decisions, including  the Industrial
     Transformer/Sol Lynn  site
DOCUMENT NUMBER«
DOCUMENT DATE.
NUMBER OF PAGES:
AUTHOR.

COMPANY/AGENCY:.
RECIPIENT:

DOCUMENT TYPE:
DOCUMENT TITLE:
         127
     04/07/88
     002
     John Fleeter for Robert E. Layton Jr.,
     P.E., Regional Administrator
     U.S. EPA Region VI
     Honorable Martin Frost, Member, United
     States House of Representatives
     Correspondence
     Explanation of involvement of Sol Lynn
DOCUMENT NUMBER:
DOCUMENT DATE.
NUMBER OF PAGES.
AUTHOR:
COMPANY/AGENCY.
RECIPIENT.

DOCUMENT TYPE.
DOCUMENT TITLE.
         128
     04/14/88
     001
     Greg Tipple for David H. Sorrells, P.E.,
     Chief,"Superfund Section, Hazardous and
     Solid Waste Div.
     Texas Water Commission
     Lawrence M. Kagan, Kagan-Edelman
     Enterprises
     Correspondence
     Industrial Transformer Superfund Site;
     request that the right-of-entry to property
     for access to monitoring well not be
     terminated
                            A-2

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SITE NAME:
SITE NUMBER.
       ADMINISTRATIVE RECORD INDEX

                ADDENDUM

       Sol Lynn Phase II
       TXD 980873327
DOCUMENT NUMBERt
DOCUMENT DATE i
NUMBER OF PAGES.
AUTHORi
COMPANY/AGENCY:
RECIPIENT.
DOCUMENT TYPEi
DOCUMENT TITLE:
                129
            04/15/88
            001
            Julie T. Cadogan
            U.S.  EPA Region VI
            Sherry Fuerst, U.S.  EPA Region VI
            Record of Communication
            Air Stripper regulations
DOCUMENT NUMBER.
DOCUMENT DATE.
NUMBER OF PAGES.
AUTHORi
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT
DOCUMENT
TYPE.
TITLE.
    13C
04/26/88
001
Robert Rountree, Remedial Investigation
Unit, Superfund Section, Hazardous and
Solid Waste Division
Texas Water Commission
Thomas W. Hoskings, Ph.D., P.E., Department
Head, Radian Corporation
Correspondence
Confirmation of conversation on 04/15/88
which discussed the Objective and Criteria
for the Industrial Transformer site
DOCUMENT NUMBER:
DOCUMENT DATE.
NUMBER OF PAGES;
AUTHOR:

COMPANY/AGENCY.
RECIPIENT:
DOCUMENT
DOCUMENT
TYPE:
TITLE.
    131
05/24/88
003
Carl E. Edlund, Chief, Superfund Program
Branch
U.S. EPA Region VI
Carl Hickam, RS, Senior Regional
Representative, ATSDR/ROHR-Region VI
Memorandum and Attachment
Comments on Draft Health Assessment for the
Industrial Transformers Site
                            A-3

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SITE NAME:
SITE NUMBER:
ADMINISTRATIVE RECORD INDEX

         ADDENDUM

Sol Lynn Phase II
TXD 980873327
DOCUMENT NUMBER.
DOCUMENT DATE:
NUMBER OF PAGES<
AUTHOR.
COMPANY/AGENCY.
RECIPIENT.
DOCUMENT TYPE.
DOCUMENT TITLE:
         132
     07/08/88
     001
     Jon Rauscher
     U.S. EPA Region VI
     Sherry Fuerst, U.S. EPA Region VI
     Memorandum
     Comment on the excess cancer risk from
     exposure to trichloroethylene at the
     Industrial Transformer Superfund Site
DOCUMENT NUMBER.
DOCUMENT DATE.
NUMBER OF PAGES:
AUTHOR.

COMPANY/AGENCY:
RECIPIENT.
DOCUMENT TYPE.
DOCUMENT TITLE.
         133
     07/12/88
     005
     Robert Rountree, Remedial Investigation
     Unit
     Texas Water Commission
     Texas Water Commission Files
     Memorandum and Attachments
     Industrial Transformers-Meeting with Bill
     Chadick, ERT & Jim Mutch, Gulf States
     Utilities, Date. 07/07/88; meeting to
     discuss the results of the groundwater
     analyses
DOCUMENT NUMBER.
DOCUMENT DATE.
NUMBER OF PAGES.
AUTHOR.
COMPANY/AGENCY.
RECIPIENT.
DOCUMENT TYPE.
DOCUMENT TITLE.
         134
     07/19/88
     013
     Sherry Fuerst, Texas Remedial Section
     U.S. EPA Region VI
     Robert Rountree, Texas Water Commission
     Correspondence and Attachments
     EPA's comments based on review of the Site
     Investigation, Feasibility Study and
     Quality Assurance/Quality Control Reports
                            A-4

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SITE NAME:
SITE NUMBER:
                ADMINISTRATIVE RECORD INDEX

                         ADDENDUM

                Sol Lynn Phase II
                TXD 980873327
DOCUMENT NUMBERi
DOCUMENT DATEi
NUMBER OF PAGES>
AUTHORi
COMPANY/AGENCYi
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
                         135
                     07/20/88
                     007
                     Robert Rountree, Remedial Investigation
                     Unit, Superfund Section, Hazadous and Solid
                     Waste Division
                     Texas Water Commission
                     Tom Hoskings, Radian Corporation
                     Correspondence
                     Remedial Investigation/Feasibility Study
                     Phase II Comments as discussed in the
                     meeting held 06/30/88
DOCUMENT NUMBER.
DOCUMENT DATE.
NUMBER OF PAGES.
AUTHOR.
COMPANY/ AGENCY:
RECIPIENT.
DOCUMENT
DOCUMENT
         TYPE.
         TITLE.
    136
07/21/88
177
Riaz Ahmed, Program Manager, Thomas
Hoskings, Project Director, and Mary
McGill, Geologist
Radian Corporation
Sherry Fuerst, Remedial Project Manager,
U.S. EPA Region VI
Correspondence and Final Draft Report
Investigation Report, Phase II Groundwater
Contamination, Industrial Transformer
Superfund Site, Houston, Texas; objective
is to assess extent of contamination in
water-bearing zones
DOCUMENT NUMBER.
DOCUMENT DATE.
NUMBER OF PAGES:
AVTHOR.
COMPANY/AGENCY.
RECIPIENT.

DOCUMENT TYPE.
DOCUMENT TITLE.
                         137
                     07/21/88
                     235
                     Riaz Ahmed, Program Manager, Thomas
                     Hoskings, Project Director, Karen Miller
                     and Mark Colonna, Engrs
                     Radian Corporation
                     Sherry Fuerst, Remedial Project Manager,
                     U.S. EPA Region VI
                     Correspondence and Final Draft Report
                     Feasibility Study, Phase II, Groundwater
                     Contamination, Industrial Transformer
                     Superfund Site, Houston, Texas; objective
                     is to document findings of TCE

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SITE
SITE
NAME:
NUMBER:
ADMINISTRATIVE RECORD INDEX

         ADDENDUM

Sol Lynn Phase II
TXD 980873327
DOCUMENT NUMBERt
DOCUMENT DATE*
NUMBER OF PAGESi
AUTHORt
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT TYPEi
DOCUMENT TITLE:
DOCUMENT NUMBER:
DOCUMENT DATEi
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
                    138
                07/21/88
                038
                Riaz Ahmed,  Ph.D., P.E., Program Manager,
                and Thomas Hoskings, Ph.D., P.E., Project
                Director
                Radian Corporation
                Sherry Fuerst, Remedial Project Manager,
                U.S. EPA Region VI
                Correspondence and Final Draft Report
                Phase II Quality Assurance and Quality
                Control Report, Industrial Transformer
                Superfund Site; a system of checks which
                enables documentation of data reliability
                    139
                08/10/88
                003
                Jon Rauscher
                U.S.  EPA Region VI
                Sherry Fuerst, U.S. EPA Region VI
                Memorandum
                Comment on the Health Assessment for the
                Industrial Transformer Superfund site
DOCUMENT NUMBER:
DOCUMENT DATEi
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLE:
                    140
                08/10/88
                001
                Community Relations Staff
                U.S. EPA Region VI
                Public
                Public Notice
                Notice of Public Availability announcing
                the availability of the Administrative
                Record for the Industrial Transformer
                Superfund Site
                            A-6

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 f
SITE NAME:
SITE NUMBER:
       ADMINISTRATIVE RECORD INDEX

                ADDENDUM

       Sol Lynn Phase II
       TXD 980873327
DOCUMENT NUMBER.
DOCUMENT DATE:
NUMBER OF PAGES>
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT
DOCUMENT
TYPE:
TITLE:
    141
08/12/88
001
John S. Reese, P.E., General Manager
NEPCCO
Carl Edlund, Chief, Superfund Program
Branch, U.S. EPA Region VI
Correspondence
Comments on possible remedies for
groundwater contamination
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHORi
COMPANY/AGENCY:
RECIPIENT:

DOCUMENT'TYPE:
DOCUMENT TITLE:
                142
            08/16/88
            002
            Lawrence M. Kagan
            Kagan-Edelman Enterprises
            Carl Edlund, Chief, Superfund Program
            Branch, U.S. EPA Region VI
            Correspondence
            Industrial Transformer Site; Houston,
            Texas, comments on EPA's proposed remedial
            plan to remedy groundwater contamination
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
DOCUMENT TITLEi
                143
            08/25/88
            029
            Mary Kay Hendricks, CSR
            A Better Court Reporting Service
            U.S. EPA Region VI
            Public Meeting Transcript
            Transcript of Proceedings for the
            Industrial Transformer (Sol Lynn) Superfund
            Site Public Meeting held August 25, 1988
                            A-7

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                ADMINISTRATIVE RECORD INDEX

                         ADDENDUM
SITE NAME:       Sol Lynn Phase II
SITE NUMBER:    TXD 980873327
DOCUMENT NUMBER.          144
DOCUMENT DATEi       09/09/88
NUMBER OF PAGESi      006
AUTHOR.              Patrick R.  Cowlishaw
COMPANY/AGENCYi      Cohan,  Simpson,  Cowlishaw,  Aranza & Wulff
RECIPIENT!           Carl Edlund,  Chief,  Superfund Program
                     Branch, U.S.  EPA Region VI
DOCUMENT TYPEi       Correspondence
DOCUMENT TITLE:      Industrial  Transformer (Sol Lynn) Site;
                     comments prepared by ERT regarding the
                     Phase II Remedial Investigation Report and
                     Feasibility Study prepared  by Radian
                     Corporation
                            A-8

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ATTACHMENT B

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Sol  Lynn
Houston, Texas
Responsiveness Summary

This community relations responsiveness summary is divided into two sections:

Section I:  Background on Community Involvement and Concern
            This section provides a brief history of community interest and
            concerns raised during the remedial planning activities at the
            Sol Lynn Superfund site.

Section II: Summary of Public Comments Received During the Public Comment
            Period and the EPA Responses to Comments
            Both the written and spoken comments are categorized by topics.
            EPA responses to these relevant major topics are also presented.

I. Background on Community Involvement

    Initiation of studies on Industrial Transformer was announced by TWC at a
    public meeting in Houston on September 24, 1986.  Evaluation of the site
    was divided into two separate studies:  1) surface soil contamination; 2)
    groundwater contamination.  The study addressing surface soil contamination
    was completed in December 1987.   On January 21, 1988, a news release was
    issued stating that a public meeting would be held on February 2, 1988,
    to discuss the proposed remedy for surface contamination at the site.

    An EPA prepared fact sheet which described alternative remedial actions
    for the soil contamination along with the EPA preferred alternative was
    sent to the interested and affected public shortly after the public
    meeting was announced.  EPA and TWC conducted the 7:00 pm public meeting
    at the Astro Village Hotel on February 2, 1988.  Approximately 35 people
    attended the public meeting.

    On August 8, 1988, a news release announced that a public comment period
    on the groundwater study would begin on August 10, 1988 and end on
    September 9, 1988.  The news release also announced that a public meeting
    would be held on August 25, 1988, at the Astro Village Hotel, Houston, Texas,

    An EPA prepared fact sheet describing the alternative remedial actions
    for the groundwater study along with the EPA preferred alternative was
    sent to the site mailing list shortly after the meeting and comment
    period was announced.  EPA and TWC conducted the 7:00 p.m. public meeting
    on August 25.  Approximately 15 people attended the meeting.  Only two
    questions were asked and no comments were made during the public meeting.

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II.   Summary of Public Comment Received During Public  Comment  Period and
     Agency Responses

     This  section  gives the  EPA's  responses  to the  comments  received during
     the public comment period. There  were  two verbal  comments  made at  the
     public meeting  and nine written  comments  received  by the  EPA
     during public comment.

     A.   Comments  at the public meeting

         i.  By Ray  McMullen on behalf  of  a  landowner.

         Comment #1

         Who is responsible  for the  fence, barrels  and  other debris  on the
         land next to  the contaminated  area?

         Response

         The property  owner  signed an access agreement  with  the  Texas Water
         Commission.  This access  agreement  gave the Texas Water Commission
         the right to  use the land.   The Texas Water Commission  is  responsible
         for removing  the fence, barrels and any other  material  generated
         during its  investigation.

         Comment #2

         The name  I've seen  associated  with  the cause  of  the contamination is
         Sol  Lynn.  What happened  to  h-im and is he  paying for  any of the
         cleanup or  is it only being  funded  by the  Superfund?

         Response

         The Environmental Protection Agency has been  in  contact with
         Mr. Lynn  and  other  potentially responsible parties  to try to recoup
         the expenses  of the remedial actions  which have  occurred and which
         are scheduled to occur at the  site.

         ii. Comments  by Steve Hupp of  the Harris County  Pollution Control.

         Comment #3

         What is the anticipated total  amount  of TCE emitted into the air during
         the life  of this project? What air  cleaning equipment was considered to
         eliminate the TCE emissions  into the  atmosphere? What  is the odor
         threshold for TCE?

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         Response

         We estimate 50 pounds per year of TCE will  be  emitted  into the air
         if no emission control  devices are used  and less  than  10  pounds per
         year if any are used.

         The carbon adsorption canister was the only emissions  control  device
         considered during the feasibility study.

         The lowest reported odor threshold limit  is 1.134 mg/m^.

B.  Written Comments

    i.  Lawrence Kagen of Kagen-Edelman Enterprises, an adjacent  landowner:

        Comment #4

        I am concerned about the subsidence danger to my property  caused by
        the EPA withdrawing groundwater from the  property.  Who will  be
        responsible for the damage caused to my property by the settling and
        possible flooding caused by the lower ground elevation  caused by the
        withdrawal of the groundwater?

        Response

        The City of Houston is experiencing subsidence  problems from
        groundwater pumpage.  The majority of this subsidence problem is
        from pumping of municipal wells.  These wells can pump  up  to one
        million gallons of water per day.  The system discussed in the
        Record of Decision for the remediation of  the TCE  contaminated
        groundwater would pump about 3.2 million  gallons over a 10 year
        period.  We estimate the subsidence to be  less  than'one inch for
        the ten year life of the system.  The subsidenece will  be  less if
        the treated groundwater is reinjected into the  ground than if
        it is discharged into publicly owned treatment  works.  The discharge
        options will be evaluated in the remedial  design stage  of  the project.

   ii.  Prepared by ERT, an engineering company,  for the law firm  of Cohan,
        Simpson, Cowlishaw, Aranz and Wulff, representing Gulf  States
        Utilities, a potentially responsible party.

        Comment #5

"••       The volume of tricholorethylene contaminated water in the  uppermost water-
        bearing unit may be overstated.  The hydrocone  testing  determines
        groundwater quality very crudely and the data should be viewed with caution,

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Response

The EPA tries to be "cautious" with our estimates erring on the side
of conservatism.  A sensitivity analysis was done comparing the effect
of volume changes on the cost of each alternative.  This analysis was
considered in the alternative selection.  This analysis indicated
that air stripping becomes more cost effective as the volume of treated
water increases.

The cone penetrometer is one of many techniques that can be utilized to
trace groundwater contamination.  Like most other techniques it has
its limitations. .Yet when evaluating its effectiveness versus cost,
it proved to be a useful technique for this investigation.

Comment #6

The three monitoring wells completed in the intermediate zone are
inadequate to determine the extent of contamination, the flow
direction or any aquifer parameters.

Response

As stated on page 7 of the Record of Decision, these three wells were
not used to define the extent of contamination.  We believe three
monitoring wells adequately indicate the flow direction and many
other aquifer parameters.  The extent of contamination will be
determined during the design phase of the project.

Comment # 7

There is a probability the intermediate water-bearing unit
contamination came from poor monitor well construction or from the
on site groundwater production well.

Response

We disagree.  Monitoring wells were installed according to approved
specifications.  Care was taken to avoid cross-contamination by double
casing each well.

The on site groundwater production well may have contributed to the
contamination by producing a vertical channel  for the movement of the
TCE.  All wells on site not used in remediation or for postclosure
monitoring will be plugged.

Comment #8

Both the upper and intermediate water-bearing units are not usable
potable water supply sources because of low yield and high Total
Dissolved Solids,

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Response

The Total Dissolved Solids in the upper water-bearing zone ranges
from about 2300 mg/1 -to 3700 mg/1 and in the second water-bearing
zone from 1000 to 1650 mg/1.  Although these are higher than the
secondary drinking water standard of 500 mg/1 according to Chemical
Analysis of Public Water Supply by the Texas Department of Health,
1983, there are numerous water supplies in Harris County and throughout
the State that are within these ranges.  As stated on page 7 of the
Record of Decision, the EPA identifies a potential drinking water
supply as any body of water under 10,000 mg/1 Total Dissolved Solids;
therefore, the groundwater at Industrial Transformers could not be
eliminated as a potential water supply.  The yield is low in these
water-bearing zones, but they do provide enough water to be considered
potential water supplies.

Comment #9

ERT disputes the application of drinking water standard to water
bearing zones not usable for potable purposes.

Response

As stated in response to comment #8, the groundwater at Industrial
Transformers is considered a potential water supply.  As such, drinking
water standards apply in defining the extent of remediation.

Comment
The impacts of groundwater remediation need to be studied before a
recovery system is proposed.  This includes water bearing unit yield
and the potential  for subsidence adversely impacting the adjacent 610
Highway.

Response

See comment #4.

Comment 111

The EPA inappropriately eliminated directly discharging groundwater
to a Publicly Owned Treatment Works (POTW).

Response

As stated in the Record of Decision on pages 16 and 23, the method of
discharge has not been determined.  In alternatives 3, 4, and 5
discharging into a POTW and reinjection into the groundwater zone are
still being considered.  This decision will be made during design.

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Response

As stated in the Record of Decision on pages 16 and 23,  the method of
discharge has not been determined.  In alternatives 3,  4, and 5
discharging into a POTW and reinjection into the groundwater zone are
still being considered.  This decision will  be made during design.

Comment #12

There is no basis for selecting air stripping over direct activated
carbon treatment.

Response

The EPA disagrees.  The air stripping system, as described in the
Record of Decision, provides many advantages over direct carbon
adsorption.  The high total dissolved solids in the groundwater make
carbon adsorption less effective than air stripping;  other organics
will  compete with the TCE for adsorption sites.  The  high suspended
solids also cause the carbon unit to clog, drastically  reducing the
effectiveness of the treatment process.  The cost effectiveness
increases with air stripping as the volume of groundwater to be treated
increases.  This becomes important since the volume of  contaminated
groundwater in the second water-bearing zone will be  defined during
the design phase.

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ATTACHMENT C

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                     TEXAS  WATER COMMISSION
B. J. Wynne, III, Chairman

Paul Hopkins, Commissioner

John O. Houchins, Commissioner

J. D.

MW^r
Karen A. PKHfips,
J Counsel
i,Jv; ^
                            Allen Beinke, Executive Director

                         September 19,  1988

  Allyn M. Davis,  Ph.D., Director
  Hazardous Waste  Management  Division
  U. S. Environmental Protection Agency
  Region VI
  1445 Ross Avenue
  Dallas, Texas    75202-2733

  Re:   Industrial  Transformers Superfund  Site
       Draft Record of Decision

  Dear Dr. Davis:

  We have reviewed the proposed Record of Decision  (ROD)  for the
  Industrial Transformers Site.   We have  no objection  to  the
  selected remedy  of collection, on-site  air stripping, and
  discharge (Alternative 4) as described  in the draft  ROD of
  September 14,  1988.

  Sincerely,
  Allen P. Beinke
  Executive Director
                                                                     . Tf

      P 0. Box 13087 Capitol Station • 1700 North Congress Ave. • Austin, Texas 78711-3087 • Area Code 512/463-7830

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