United States
            Environmental Protection
            Agency
               Office of
               Emergency and
               Remedial Response
EPA/ROD/R06-87/023
September 1987
SEPA
Superfund
Record of Decision:
             Crystal City Airport, TX

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                                    TECHNICAL REPORT DATA
                             !Please read Inunctions on the revene before completing)
  REPORT NO.
 EPA/ROD/R06-87/023
              3. RECIPIENT'S ACCESSION NO.
 4. TITLE ANO SUBTITLE
 SUPERFUND RECORD OF  DECISION
 Crystal City Airport,  TX
 First Remedial Action  - Final
              5. REPORT DATE
                        September 29, 1987
              6. PERFORMING ORGANIZATION CODE
 7. AUTMOR(S)
                                                            8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME ANO ADDRESS
                                                             10. PROGRAM ELEMENT NO.
                                                             11. CONTRACT/GRANT NO.
 12. SPONSORING AGENCY NAME ANO ADDRESS
 U.S. Environmental  Protection Agency
 401 M Street, S.W.
 Washington, D.C.   20460
              13. TYPE OF REPORT ANO PERIOD COVERED
              	Final ROD Report
              14. SPONSORING AGENCY CODE
                        800/00
18. SUPPLEMENTARY NOTES
 6. ABSTRACT
    The Crystal City  Airport (CAA) site, comprising  approximately 120 acres,  is  located
 in Zavala County,  Texas.   CCA began operations  during World War II as a military
 installation for transporting and detailing persons of Japanese descent.   In 1949,  the
 U.S. Government deeded the airport to Crystal City.  Since then, the city  has operated
 the facility as a  municipal airport.  Several private aerial pesticide applicating
 companies conducted  business at the airport until 1982.  In April 1983, the  Texas
 Department of Water  Resources investigated the  site because of the potential threat to
 local residents of waste  pesticides left by applicating companies no longer  in
 operation.  Surficial  soil at the site was found to be highly contaminated with
 pesticides.  In October 1983, an Immediate Removal  Action, initiated by the  U.S.  EPA,
 consolidated 40 yd^  of waste and 50-70 drums in two onsite disposal cells.   In  May
 1984, a second removal action disposed of 19 drums  offsite and secured the site with a
 fence.  Approximately  12,000 yd^ of surface soil are contaminated with pesticides
 including:  DDT, toxaphene and arsenic.
     The selected remedial action includes:  onsite  consolidation of contaminated soil,
 drums and buildings; multi-layer RCRA capping;  offsite injection well; disposal of
 decontaminated liquids; and fencing.  The estimated present worth cost for this remedy"
 is £l,600,000.
 7.
                                KEY WORDS ANO DOCUMENT ANALYSIS
                  DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS  C.  COSATI Field/Group
 Record of Decision
 Crystal City Airport,  TX
 First Remedial  Action  - Final
 Contaminated Media:  surface soil
 Key contaminants: arsenic, DDT,
  toxaphene, pesticides, metals
 8. DISTRIBUTION STATEMENT
KFA form 2230-1 (R»». 4-77)   PNBVIOUS IOITION i» OS*OL«TK
19. SECURITY CLASS 
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EPA P«n» 2220.1 (Rev. 4.77) (*•«•*••)

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                 DECLARATION FOR THE RECORD OF DECISION
Site Name and Location

The Crystal City Airport Superfund site is located in the City of Crystal
City, Zavala County, Texas, in the south-central part of Texas.

Statement of Purpose

This decision document represents the selected remedial action for this
site developed in accordance with CERCLA, as amended by SARA, and to the
extent practicable, the National Contingency Plan.

The State of Texas has been provided a reasonable amount of time to review
the proposed remedy but has remained silent.

Statement of Basis

This decision is based upon the Crystal City Airport administrative
record.  The attached index (Attachment A) identifies the items which
comprise the administrative record upon which the selection of a remedial
action is based.

Description of the Selected Remedy

•  Ons ite consolidation of all material which exceeds the health-based
   criteria of 100 mg/k9 total pesticides.

•  Placement of a RCRA cap over the consolidation cell.

•  Monitor site for a minimum of 30 years following construction of
   selected remedy.

•  Deep-well injection of decontamination liquids.

•  Five year review of selected remedy.

Declaration

The selected remedy is protective of human health and the environment,
attains Federal and State requirements that are applicable or relevant
and appropriate, and is cost effective.  Due to the characteristics of
the contaminants, the lack of near surface groundwater, and the imperme-
able nature of the soils, treatment of the contaminants was found to be
impracticable.
     Date              Robert E. Layton Jr.^ P.E.
                       Regional Administrator

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                             Table of Contents





                                                           Page



1.  Site Name, Location and Description 	  1



2.  Site History	  1



    o  Extent of Contamination	  2



    o  Risk from Contaminants 	  3



3.  Enforcement	  3



4.  Community Relations History 	  4



5.  Alternatives Evaluation 	  4



6.  Selected Remedy	  8



    o  Operation and Maintenance 	  9



    o  Schedule	,	  9

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               SUMMARY OF REMEDIAL ALTERNATIVE SELECTION

                          CRYSTAL CITY AIRPORT
                          CRYSTAL CITY, TEXAS

                             September 1987
SITE NAME, LOCATION AND DESCRIPTION

The Crystal City Airport Superfund Site is located in the City of Crystal
City, Zavala County, Texas, in the south-central part of Texas  (Figure 1).
The airport is owned by the City of Crystal City.  The site is comprised
of approximately 120 acres of land.  Surrounding the airport property
to the north, is land used for grazing animals, to the east is a
municipal landfill to the south are both an elementary and high school
as well as a residential area, and to the west is a residential area
(Figure 2).  The major aquifer containing potable water for the residents
of Crystal City is the Carrizo aquifer located 750 feet below the surface.

In general, the project site is in a region of low population where the    ;
economy is dominated by agriculture.  Crystal City is the county seat of   :
Zavala County and the most populated town in the county with an estimated
8,075 inhabitants from the total county population of 11,390.  The closest
large city from Crystal City is San Antonio, located approximately 100
miles northeast.

SITE HISTORY

The Crystal City Airport was first operated during World War II as a
military installation for transporting and detailing persons of Japanese
extraction.  In 1949, the U. S. Government deeded the airport property to
the city.  Since 1949 the city has operated the facility as a municipal
airport.  Several private companies conducted aerial pesticide applicating
businesses at the airport until 1982.

In April, 1983, the Texas Department of Water Resources, the predecessor
agency to the Texas Water Commission  (TWC), conducted a preliminary investi-
gation of the municipal airport after city officials voiced concern that
agricultural chemicals, left by defunct aerial operatorsr presented a threat
to local residents.  On June 13 and July 23, 1983, followup investigations
were conducted.  The results of the sampling efforts -conducted during these
investigations indicated that surficial soil at the site was highly contami-
nated with pesticides.  An Immediate Removal Action was initiated by the
Environmental Protection Agency (EPA) on October 31, 1983, to remove the
most highly contaminated materials.  During this action, approximately
40 yd3 of waste and between 50-70 drums of material were placed in two
onsite disposal cells east of the runway.  A second removal action was
initiated by EPA in May 1984, during which 19 drums were transported
off-site for disposal, a fence was constructed with a locked entrance
gate, and warning signs were posted.

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LOCATION OF CRYSTAL CITY
 AIRPORT SUPERFUNO SITE
                                    FIGURE 1

                         MAP OF WINTER GARDEN DISTRICT
              AND LOCATION OF CRYSTAL CITY AIRPORT SUPERFUND SITE

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       Figure 2
CRYSTAL CITY LAND USE

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In October 1984, the Crystal City Airport site was ranked for  inclusion  on
the National Priorities List  (sites which appear to present a  significant
risk to public health and/or the environment).  The State of Texas entered
into a Cooperative Agreement with the Environmental Protection Agency (EPA)
for $690,000 on September 28, 1985, to perform a Remedial Investigation
(RI) and Feasibility Study  (FS) at the site.  In June 1986, Ebasco Services
Incorporated was contracted by TWC to conduct the RI/FS.  Field work
began on September 28, 1986, and a draft RI report was submitted on
April 7, 1987.  A draft FS report was submitted on May 20, 1987.

Extent of Contamination

Table 1 summarizes the reports which were used to describe the nature and
extent of contamination.  Pathways and receptors are described in detail in
these reports.

     The primary areas found to be contaminated at the site are:

     o  The surface soil adjacent to Frank's hangar

     o  The surface soil adjacent to the southern hangar

The surficial soil occurring on the site includes the Crystal  fine sandy :
loam, the Cotulla clay, the Maverick clay loam, the Pryor sandy clay  loam u
and the Tonio fine sandy loam.  These soils range in depth from 28 to 72
inches below grade.  The soils are characterized by high clay  content and
extremely low permeabilities.  The clay contents of these soils increase
with depth.

The stratigraphy is generally consistent across the site.  Two lithologic
units of the El Pico Clay are present at the site.  The first  layer is
predominantly sandy clay with some surficial layers of clayey  to silty sand
and silty clay.  The layer extends from the surface to an average depth  of
26 feet.  Near the bottom of this layer, the sandy clay layer  occasionally
terminates above a 0.5 to 3 feet thick bed of clayey sand, silty sand or
siItstone.  The permeability of soil within the first layer of the El Pico
Clay is 4.42 x 10""° cm/sec.  The second layer consist of hard  clay with
interbeds of sandy to silty clay, silty to clayey sand, siltstone and
sandstone.  The average depth of the second layer is from 2.5  to at
least 180 feet.  For the hard claysjpresent in the lower layer, the
permeability ranges from 1.48 x 10   to 3.0 x 10   on/sec.

Due, in part, to the low permeability of the soil, the 'contamination  is
limited to the upper 1 to 2 feet of soil.  Table 2 shows that  maximum
level detected for selected compounds and the frequency these  were
detected during RI.  Figure 3 depicts area of contamination on the
site.  The estimated volume of contaminated soil exceeding 100 ppm
total pesticide is 12,000 yd3.

Near surface groundwater is not present below the site.  The only known
source of groundwater, Carrizo aquifer, is located 750 feet below the
surface of the site and is isolated from the contaminated surface soils
of the site by thick clay layers.  The aquifer does not appear to be  in
any danger of future contamination from the airport.

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                                  TABLE  1
               Chronology of Sampling Events/Investigation
Date

April  1983



July 1983


October 1983


February 1984


April 1984


June 1987

July 1987
Agency/Firm

Texas Department
of Water Resources,
District 8

Environmental Protection
Agency

Environmental Protection
Agency

Texas Department
ot Water Resources

Environmental Protection
Agency

EBASCO Services Incorporated

EBASOO Services Incorporated
Purpose

Initial investigation



Supplemental Sampling


Initial Removal Action


Supplemental Sampling


Final Removal Action


Remedial Investigation

Feasibility Study

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                           TAbLb 2
                  SUMMARY OF SOIL SAMPLING

COMPOUND       FREQUENCY DETECTED     MAXIMUM CONCENTRATION
                                          (MG/KG)
TOXAPHENE          43-6%                   1113
DOT                W.2Z                   25U2
ARSENIC            89-9%                   145U

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                                      RUNWAY
                                         \
j.JOO      | -100
100       300
I'tOO      (VoO       1*00     fllOO      11300      ||SOO     11700

   rSAMPUNQ GRID XCOORDINAIIS                        •
                                                                              100 mg/ko = L i
                                                                                  1900
	i	i   . i
  11100
                                                                                          QttGO
                                                                                        ARFAS OF
                                                                                  • TOTAL CONTAMINATION
                                                                                       FIGURt 3

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Surface water from the Espantosa Slough, Nueces River and Volz  Pond
(Figure 4) for the most part, meet the water quality criteria limits,
and therefore would not require treatment.  Sediment samples collected
at the same locations generally contained levels which were comparable
to background soil levels.

Samples of ambient air were collected upwind and downwind of the site
.on two separate occasions.  Based on the sample results, air quality at
the site has not been measurably degraded as a result of the surface
contamination present at the site.

Risk from Contaminants

The contaminants of greatest concern at the site  (toxaphene, DDT, and
arsenic) were chosen from the compounds detected based on their widespread
distribution over the entire site as well as the relative toxicity and
concentration.  A risk assessment was conducted using these three indicator
compounds.  The first step in the exposure assessment required  the
identification of potential receptors.  Target receptors identified
in the assessment include:

     o  Occasional users of the site such as aircraft personnel and        •
        passengers, recreational users, and airport maintenance personnel,1-
        and
     o  Residents of housing area  (adults and children).

Target concentrations or clean-up levels,were developed which will
attain, to the extent practicable, a 10   to 10~5 risk level.   In an
effort to develop a single criteria, a combined pesticide level of 100
mgAg was proposed for the contaminants of concern.  This level will
approach a 10~6 (one in one million) risk level throughout the  entire
site for both casual onsite exposure (15 days/ year) and residential
children exposure as well as attain a 10   risk level for residential
adult exposure.  The 100 mgAg level approaches a 10   (10 in one
million) risk level for onsite exposure of 220 days/year.  The  Agency
for Toxic Substances and Disease Registry (ATSDR) has concurred with
this level of protection.

Results of the assessment indicate that remedial action is required to
reduce the potential for public health exposure through:

     o  Direct contact with contaminated soils;

         o  Ingestion of contaminated soils; and
         o  Inhalation of contaminated dust particles.

ENFORCEMENT

Five potentially Responsible Parties (PRPs) have been identified including
the City of Crystal City .  Four of the PRPs are no longer in business,
and the City of Crystal City appears to be unable to finance the cleanup.

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U SURFACE WATER SAMPUNO LOCATION
  SEDIMENT SAMPUNO LOCATION
  PUBLIC DRINKING WATER WELL.

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COMMUNITY RELATIONS HISTORY

On October 4, 1985, the U.S. Environmental  Protection Agency (EPA)
issued a new release announcing that  funds  had been awarded  to  the
Texas Water Commission  (TWS).  The money was  to conduct  studies on  the
Crystal City Airport site.

The TW2 made a presentation  to the Mayor, City Council and City Manager
of Crystal City on September 9, 1986.  The  meeting was to discuss what
activities would occur including on-site data gathering.

The completion of the studies was announced to the public via a news
release issued by EPA on July 24, 1987.  Along with an announcement
for the August 20, 1987, public meeting to  discuss the proposed remedy
for the site.

An EPA prepared fact sheet which described  alternative clean up plans
along with the EPA preferred alternative was  sent to the interested and
affected public on August 10, 1987.  The fact sheet gave a brief site
history, described the process and alternatives and gave details about
the public comment period and public meeting.

On the afternoon of August 20,.1987, EPA and  1WC staff met with City
leaders to brief them of the study findings and alternatives at 7:00 pm
that evening, EPA and 1WC conducted a public  meeting at  the  Fly Junior
High School Cafeteria.  Nearly 45 people attended the public meeting.

Further details concerning community relations are contained in
Appendix B.

ALTERNATIVES EVALUATION

The Feasibility Study for the Crystal City  Airport site  determined  what
actions, if any, would be appropriate as part of a permanent remedy for
the site.  Several alternative remedial technologies were developed to
mitigate damage to, and provide protection  of public health, and the
environment from past and future releases of  contaminants.   A response
action toward mitigating the release of contaminants is appropriate in
accordance with the National Contingency Plan (NCP), 40 CFR  Part 300.68.

Based on the results of the remedial investigation, objectives  and
criteria were developed for use in evaluating alternatives during the
Feasibility Study (Table 3).  In addition to  the the requirements of
the NCP the Superfund Amendments and Reauthorization Act of  1986 (SARA)
includes a strong preference for permanent  solutions and a requirement
that all onsite remedial actions attain legally applicable or relevant
and appropriate Federal and State standards,  requirements, criteria or
limitations (ARARs).

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                                  TABLE 3
                       OBJECTIVES OF REMEDIAL ACTION
                         CRYSTAL CITY AIRPORT RI/FS
    PATHWAY
    Soils-Short Term
    Soils - Long Term
    Air - Short Term
    Air - Long Term
    Surface waters-
      short term
    Surface waters-
      long terra
OBJECTIVE

Minimize direct
exposure to workers
onsite.
Reduce levels to
prevent chronic
or acute exposure.
Prevent significant
deterioration, onsite
and offsite.

Prevent significant
deterioration, onsite
and offsite.

Minimize surface
water degradation.
Prevent surface water
degradation.
    Groundwater
No groundwater
encountered.
CRITERIA

Perform remedy
in areas of
contamination
above site specific
cleanup criteria.

Attain site specific
cleanup criteria of
100 mgAg total
pesticides. *
                    t
Maintain background •'
air quality levels  *"
or OSHA, NIOSH Standards.

Maintain background
air quality levels.
Maintain background
surface water quality
or ambient water
quality criteria at
site boundary.

Maintain background
surface water quality
or ambient water
quality criteria at
discharge to surface
waters.

No groundwater
encountered.
* Level corresponds to a 10-10   excess lifetime cancer risk factor.

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In addressing permanence and long-term effectiveness of remedial actions,
EPA must consider the following:

    -  long-term uncertainties of land disposal;
    -  goals and requirements of the Resource Conservation and Recovery
       Act  (RCRA);
    -  persistence/ toxicity and mobility of the hazardous substances of
       concern;
    -  short and long-term potential for adverse human health effects;
    -  longterm maintenance costs, including remedy failure costs;
    -  potential threat to human health and the environment from the
       excavation, transportation, and redisposal, or containment of
       hazardous substances or pollutants or contaminants.

SARA establishes a preference for remedial actions that utilize treatment
to permanently and significantly reduce the volume, toxicity, or mobility
of hazardous substances.  Offsite transport and disposal without treatment
is the least preferred option where practicable treatment technologies
are available.

A number of potentially applicable remedial technologies were studied       *
for the Crystal City Airport site.  Treatment alternatives for source       •'
actions were developed ranging from an alternative that would eliminate/    k
minimize the need for long-term management at the site, to an alternative
using, as a principal element, treatment that would significantly reduce
the toxicity, mobility, or volume of site waste.

The following broad criteria was used in the initial screening of alternatives
and is consistent with the draft guidance distributed pursuant to SARA.

1.  Effects of the Alternative.  The effects of each alternative should
    be evaluated in two ways;   (i) whether the alternative itself or
    its implementation has any adverse environmental effects; and  (ii)
    for source control remedial actions, whether the alternative is
    likely to achieve adequate control of source material, or for offsite
    remedial actions, whether the alternative is likely to effectively
    mitigate and minimize the threat of harm to public health, or the
    environment should be considered.

2.  Implementabi1ity.  Alternatives must be feasible for the location
    and conditions of the release, applicable to the problem, and represent
    a reliable means of addressing the problem.

3.  Cost.  For each alternative, the cost of installing or implementing
    the remedial action must be considered, including operation and
    maintenance costs.  Cost is an important factor when comparing
    alternatives which provide similar results, however, it is not used
    to discriminate between treatment and nontreatment alternatives.

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After this initial screening of alternatives, eight alternatives were
retained for detailed evaluation and are discussed below and  summarized
on Table 4.

ALTERNATIVE 1  (NO ACTION)

The Superfund statute requires full consideration be given  to a no-action
alternative.  No remediation of the soil contamination would  occur with
this alternative.  This alternative does not prevent future migration
of contaminants, does not clean up the existing contamination and does
not prevent accidental exposure to site contamination.   The associated
$0.6 million present worth cost of this alternative is for  fencing and
environmental monitoring.  Under this alternative the waste would neither
be consolidated nor isolated; therefore, the possibility of further
migration and exposure to hazardous waste is not reduced.

ALTERNATIVE 2  (IN PLACE CONTAINMENT- ASPHALT CAP)

Due to the impermeable nature of the soils, the lack of  near  surface
groundwater resources and the probable future use of the site as an       - j
airport; the capping alternative would be highly effective, both as a
source containment technology and as an isolation shield to protect        **
against physical contact with the waste.

A 7.92 acre asphalt cap would adequately isolate the areas  of the site
which exceed the 100 mg/kg clean up limit as well as the areas where
the four disposal cells are located.  A nine inch cap constructed of
asphalt rather than a five foot RCRA cap was considered  since
the height of a RCRA compliant cap would severely limit  the usage of
the airport since soil contamination is present along areas of the
runway and taxiways.  Isolating waste in place with a RCRA  cap would
create an unnecessary hazard for landing aircrafts.  An  asphalt cap,
rather than a RCRA compliant cap, would enable the site  usage to remain
as an airport and still provide an effective barrier to  all pathways  of
migration.

The cap would require periodic maintenance.  Any construction at the
airport would need to consider the possibility of exposure  to the untreated
waste below the cap.  The estimated present worth cost for  this alternative
is $2.0 million, including 30 years of cap maintenance.

ALTERNATIVE 3  (CONSOLIDATION - RCRA CAP)

Consolidating the waste (contaminated soil, drums, buildings) and capping
with a multi-layered cap provides similar results as simply capping in
place; however, the land use may be maintained as an airport.  Decontami-
nation liquids would be disposed of at a secure offsite  injection well.

The waste would be consolidated in an area onsite which  would pose no
hazard to landing aircraft.  The cell cap will be specifically designed
to protect against rainfall infiltration and rainfall erosion.  The
disposal cell will be approximately 190 x 190 feet, excavated to a
depth of 17 feet.  The estimated cost of this alternative is  $1.6 million.
Failure of this remedy is unlikely as long as proper maintenance of the
cap is conducted.

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                           TABLE 4






       SCREENING SUMMARY Of REMEDIAL ALTERNATIVES




                    CRYSTAL CITY AIRPORT




EFFECTIVENESS                FEASIBILITY      COST
Clean-up Protects Meets Reduces Capitol/O&M
Concepts HH&E ARARs MTV Tech Failure Rationale
No Action —

Asphalt 0
cap -H-

Consolidation
RCRA Cap + . +

Landfill
without
treatment + *

Landfill
with
Solidification + +

0

*

*


*


+

0

0

0


0


0

0

0

0


0


"
§(m)
-H- 0.6 Retained tor comparative
purposes
•H- 2.0 Etfective containment ot
contaminant soils/
materials; asphalt cap
would be in violation ot
ARARs.
•H- 1.6 Most ettective alternative;
similar risks as more
costly alternatives;
relatively simple to
implement.

- 2. 1 Removes exposure pathway
hazards; rigid design
consideration; increased
cost tor no decrease in
risk.
3.8 Ettective isolation remedy;
increased cost tor very
little decrease in risk;
r Alternative 3 essentially
achieves same risk without
j' increasing volume ot: wiste.

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                                                    TABLE 4 (CONT.)

                                     SCREENING SUMMARY OF REMEDIAL ALTERNATIVES

                                                  CRYSTAL CITY AIRPORT

                              EFFECTIVENESS                   FEASIBILITY        COST
Clean-*up
Concepts
 Integrated
 Incineration
 System
Protects
HH&E
Meets
ARARs
 Offsite
 landfill
 Critical
 Pressure
 Unit
Reduces
MTV
*
*
*
0
0
0
           Capitol/O&M
Tech         Failure
              $(m)
Rationale
                                                            11.4     Innovative system requiring
                                                                     further study during design.
                                                                     Difficult to implement
                                                                     incinerator onsite;
                                                                     significant maintenance
                                                                     required; not effective
                                                                     in reducing toxicity of
                                                                     arsenic.

                                                             7.0     Tranportation hazards
                                                                     associated with removing
                                                                     waste from site; increase
                                                                     cost and risk relating to
                                                                     other containment remedies.
                                                            16.1     Innovative technology re-
                                                                     quiring further study
                                                                     during design; system
                                                                     operation would be
                                                                     difficult; effectiveness
                                                                     is questionable.

                                                      O&M:   Operation and Maintenance
                                                      HH&E:   Human Health and the Environment
                                                      ARARs:  Applicable or relevant and
                                                              appropriate requirements
                                                      M: Mobility
                                                      T: toxicity
                                                      V: Volume

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ALTERNATIVE 4  (CONTAINMENT WITHOUT TREATMENT-LANDFILL)

Untreated contaminated soil, drums/ buildings would be placed  in a
landfill, designed in accordance with Section 264.301 Subpart  N of
RCRA.  Liquids generated during construction activities would  be disposed
at an offsite injection well.  The effectiveness of this alternative is
similar to alternatives 2 and 3.  Disadvantages with this remedy include
the cost of remedy failure and the rigid design consideration  required.
An accurate estimate of the volume of waste to be placed in the landfill
is required to adequately design the system.  The estimated present
worth cost is $2.0 million for this remedy.  According to manufacturers
of lining materials, a liner is expected to last at least 100  years.
Should liner fail at that time, the present worth failure cost was
estimated at $100,000  The total present worth cost, including failure
cost, is $2.1 million.

ALTERNATIVE 5  (CONTAINMENT WITH TREATMENT - LANDFILL)

The landfill would be designed in accordance with RCRA landfill require-
ments including cap requirements.  The contaminated material would be
treated (solidified), to the extent practicable, to reduce mobility.       f

The solidification procedure would include the decontamination water
and storm water runoff.  The immobilization process will not require
the offsite disposal of liquids generated during construction  activities.
Due to the impermeable nature of the soil and the lack of near surface
groundwater, the environmental and/or human health protection  achieved
by immobilizing the soils and placing the treated waste in a secure
landfill is similar to the containment protection previously discussed
in Alternatives 2,3, and 4.  The major disadvantage of Alternative 5 is
the increased cost associated with the solidification/stabilization
process which will not serve to further reduce the mobility or toxicity
of the waste at the site because the contaminants are already  highly
immobilized and fixed within a solid soil matrix.  In addition, the
construction of the RCRA landfill must be completed before starting the
solidification/stabilization process.  The cost of this remedy is $3.7
million with a failure cost of $100,000.

ALTERNATIVE 6  (INTEGRATED INCINERATION)

A mobile incinerator plant combined with appropriate exhaust gas and ash
cleaning equipment would be placed onsite.• The incinerator, designed in
accordance with Section 264.340 Subpart 0 of RCRA, would remove and destroy
the organic contaminants in the soil/materials.  A secondry treatment
technology (soil washing) would be necessary to remove the arsenic
compounds from the "treated" soil.  These technologies would be designed
as one fully integrated system.  Contaminated liquids would be collected
and mixed with the soils prior to being fed into the incinerator.
As systems are not currently available for combining incineration and
soil washing technologies, a custom  (innovative) system would  be designed.
Although Section 121(b)(2) of SARA allows for the selection of an innovative
technology, disadvantages exist with this integrated incineration system

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                                   8

including the demonstrated ability of the performance of such a system.
Due to the complexity of operation and maintenance of the component
system; the implementability and reliability are also considered dis-
advantages.  The costs associated with the remedy is $11.4 million,
including operation and maintenance costs.

ALTERNATIVE 7  (OFF-SITE LANDFILL)

All contaminated soil/ drums, demolished buildings would be disposed of at
an offsite RCRA landfill.  All contaminated liquids  (decontamination liquids)
would be disposed of at an offsite injection well.  Based on Section 121(b)(1)
of SARA, off-site transport and disposal of untreated hazardous substances
is the least favored option when others exists.  At the Crystal Airport site
other feasible alternatives have been developed; therefore, total off-site
disposal, along with no action, is considered the least preferred alternatives*
A cost of $7.0 million has been estimated for this remedy.

ALTERNATIVE 8  (CRITICAL PRESSURE FLUID EXTRACTION UNIT)

Removal from the soil, of organic contaminants and arsenic may be achieved
with soil flushing.  The organic contaminants residual would be destroyed,
off-site, in an approved incinerator.  Arsenic contaminated residual would!
be placed in an off-site landfill.  The flushing system would be designed  ^
as a two stage system.  The first stage is a critical pressure fluid
extraction unit for removing organics.  The second stage utilizes water,
enhanced with the oxidizer hydrogen peroxide, to remove arsenic compounds.
Although Section 121 (b)(2) of SARA allows for the selection of an innovative
technology, numerous disadvantages of the soil flushing system exist including
the unproven feasibility, implementability and reliability.  The estimated cost
for this alternative is $16.1 million.

Applicable or Relevant and Appropriate Requirements

Section 121 (d)(2)(A) of SARA requires EPA to give primary consideration to
remedial actions that attain or exceed applicable or relevant and appropriate
requirements (ARAR) of other federal and state public health and environmental
laws.  Environmental laws which will have an impact on the proposed remedies
at the Crystal City Airport site are summarized on Table 5.

SELECTED REMEDY

Considering the site setting (i.e., site stratigraphy and climate),
nature of the waste, and current and potential site hazards, the recommended
alternative for the Crystal City Airport is alternative 3; onsite consoli-
dation with a RCRA cap.  Consolidating and capping soil contaminated in
excess of 100 mgAg total toxaphene, DDT and arsenic would be highly effective
in protecting human health and the environment.  The effect of this
remedy would minimize the forces which drive the transport of waste from
the site as well as to remove the direct contact threat.  By consolidating
the contaminated soil away from the runway and taxiways, land use could
be maintained.  A fence would be erected around the capped area to protect
the integrity of the remedy.  Treatment will not significantly reduce the
mobility of the contaminants due to both the characteristics of the
contaminants as well as the impermeable nature of the soils.

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                                                                           TABLED

                                                              Sumary of Environmental Statutes
 Statute
 Super fortJ Amendments
 ami Reauthorizatlon
 Act (SARA)
Regulation
 Resource Conservation
 and Recovery Act
 (SARA)
 Clean WaterAct
 Occupation*! Health
 *nJ Safety Act.

 Clean Air Act
                                                                  Asphalt     RCRA
                                                 I) No action  2) Cap      3) Cap
Remedial Alternative*

                RCRA
   RCRA         landfill and
4) landfill  5) solidify
Prefers to the ,
extent practicable,
permanent and
significant
reduction of
volume, mobility
or toxicity
(Section 121(0(1)1

A) Operation of hazardous
   waste storage facil-
   ities (40 CFR 264)

B)  Hazardous waste
    land disposal ban
    (40 PCR 268)

Sets water quality
standards  (40 CFR 301,
307, 403)

Protection standards for
workers  (29 CFR 1910)

Establishes ambient air
quality standards and
emissions  limitations
 (42 U.S.C. 7401)
                                                                                           6) Incineration

                                                                                                x
   Offsita
7) landfill
   Critical
   pressure
8) unit
Department of
Transportation
hazardous
transportation

Texas Solid
Waste Disposal
Act
 Regulates the
 transport of
 hazardous waste
 (49 CFR 179)

 Operation of
 hazardous waste
 storage
Texas Clean
Air Act
 Texas Air
 Regulations,
 Section 101.4
                                                          Key.

                                                          X  ARAR will be met
                                                          -  ARAR will not be met
                                                           ] (Blank) - Not an ARAR

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Potential treatment processes which are capable of reducing the mobility
of the contaminants significantly increase the volume of the waste  (25
to 30%).  The toxicity of the organic contaminants may be reduced through
an integrated incineration system; however, innovative technologies would
be incorporated into the design in order to develop a system to remove
the arsenic compound from the soil.  Such a system does not currently exist.
Given the limited treatment methods available for the contaminants at
this site and the location of the site, Alternative 3 represents
the preferred remedy.

Details of alternative 3 are provided in Figure 5.  The site will be
monitored for a period of at least 30 years (post-closure time period
stipulated under RCRA) to ensure that no significant contaminant
concentrations migrate from the site.  If however, future migration does
occur, appropriate actions will be taken.

Operation and Maintenance (O&M)

Projected operation and maintenance requirement for the proposed remedy
include restrictions on construction activities in the capped area, periodic
inspections, warning notice replacement, and landscape and cap repair
actions (grass cutting, erosion gully repair, etc.).                       f
                                                                           b.
The State of Texas will assume responsibility for operation and maintenance
of the site.  EPA will pay 90% of the first year operation and maintenance
cost.

Schedule

- Approve Remedial Action (sign ROD)          September 1987
- Completed Enforcement Negotiations          November 1987
- Award Cooperative Agreement Amendment       November 1987
  for Design of the Approved Remedy
- Start Design                                January 1988
- Complete Design                             August 1988
- Award Remedial Action Cooperative
  Agreement Amendment for Construction
  of Approved Remedy                          October 1988
- Start Construction                          April 1989
- Complete Construction                       August 1989

No future remedial actions are anticipated.  The selected remedial action
is considered permanent.  If, however, significant uhforseen offsite
contamination occurs as a result of the site, appropriate remedial measures
will be taken.

The site will be monitored for at least 30 years to ensure the reliability
of the implemented remedial action.

SARA also states that if an alternative results in any hazardous substances,
pollutants, or contaminants remaining on site, the remedial action shall
be reviewed at least every five years to assure that human health and the
environment is being adequately protected.

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                                                                 FILTER FABRIC


                                                                SVNTHETIC LINER
                                                      ANDFILL COVER
                                                      VNTHETIC LINER
  INITIAL
  BACKFILL.
*o
                                                   *"***
ROJECT

  CRYSTAL CITY AIRPORT
    FEASIBILITY STUDY
                    SECURE LANDFILL     -
                LINING AND ANCHOR DETAIL
                                               SCALE: NOT TO SCALE
                                                                FIGURE  5

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ATTACHMENT A

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                                  Index
                              Crystal City
                                 Airport
Document Date:  4/28/83
Document Type:  Investigation Report
Originator City of Crystal City
Or1g1nator-Aff111at1on (same)
Recipient:  David Lopez
Recipient-Affiliation EPA RPM R-6
Decr1pt1on:  Frank Crop Dusting Service, Inc
Number of pages:  15
Document Number Sequence:  1
Document Date:  4/25/83
Document Type:  Crystal City Municipal Airport
Originator:  (same)
Originator-Affiliation (same)
Recipient:  EPA
Recipient-Affiliation:  EPA RPM R-VI
Description:  Pesticide Analysis
Number of pages:  5
Document Number Sequence:  2
Document Date:  4/29/83
Document Type:  Texas Dept. of Health Bureau of Labs
Originator:  Bureau of Labs
Or1g1nator-Aff1Hat1on:  Texas Dept of Health
Recipient:  David Lopez
Recipient-Affiliation:  EPA RPM R-VI
Description:  Soil Analysis
Number of paqes:  3
Document Number Sequence:  3
Document Date:  4/29/83
Document Type:  Texas Dept. of Health Bureau of Labs'
Originator:  Bureau of Labs
Originator-Affiliation:  Texas Dept of Health
Recipient:  David Lopez
Recipient-Affiliation:  EPA RPM R-VI
Description:  Soil Analysis
Number of pages:  3
Document Number Sequence:  4

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Document Date:  4/29/83
Document Type:  Texas Dept of Health Bureau of Labs
Originator:  Bureau of Labs
V1g1nator-Aff1l1at1on:  Texas Dept. of Health
 eciplent:  David Lopez
Recipient-Affiliation:  EPA RPM R-VI
Description:  Soil Analysis
Number of pages:  1
Document Number Sequence:  5
Document Date:  4/29/83
Document Type:  Texas Dept. of Health Bureau of Labs
Originator:  Bureau of Labs
Or1g1nator-Aff111at1on:  Texas Dept. of Health
Recipient:  David Lopez
Recipient-Affiliation:  EPA RPM R-VI
Description:  Soil Analysis
Number of pages:  1
Document Number Sequence:  6
Document Date:  5/3/83
Document Type:  TOWR Memo
Originator:  Henry Karnel, Jr.
Originator-Affiliation:  TOUR
Recipient:  Gary Schroeder
:edp1ent-Aff1 Hatlon:  Solid Waste and Spill Response Sec.
Description:  Investigation of an abandoned Aerial  Applicator Site at CCA
Number of pages:  5
Document Number Sequence:  7
Document Date:  5/5/83
Document Type:  memo, telephone
Originator-  Hike Dick
Or1g1nator-Aff111at1on:  TDWR
Recipient:  Skip Francis
Recipient-Affiliation:  TDWR
Description:  Crystal City Airport
Number of pages:  1
Document Number Sequence:  8

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Document Date:  5/6/83
Document Type:  memo
 Mglnator:  Vernon Francis
  •1g1nator-Aff1liat1on:  TDWR
recipient:  Gary Schroeder
Recipient-Affiliation:  TDWR
Description:  Enforcement Report
Number of pages:  4
Document Number Sequence:  9
Document Date:  5/20/83
Document Type:  Weston-Sper Correspondence
Originator:  Frank OmelHon
Or1g1nator-Aff1Hat1on:  TAT-Reglon VI
Recipient:  Charles Garza
Recipient-Affiliation:  DPO-Reg1on VI
Description:  Crystal City Hazardous Waste Site
Number of pages:  2
Document Number Sequence:  10
Document Date:  6/30/83
Document Type:  TDWR
Originator:  Dan McClellan
*r1g1nator-Aff1Hat1on:  TDWR
 ^clplent:  Gary D. Schroeder
«ec1p1ent-Aff1l1at1on:  P. E. Chief
Description:  Crystal City Municipal Airport Investigation
Number of pages:  3
Document Number Sequence:  11
Document Date:  6/30/83
Document Type:  memo
Originator:  Dan McClellan
Or1g1nator-Aff1Hat1on:  TDWR
Recipient:  Gary Schroeder
Recipient-Affiliation:  TDWR
Description:  Airport Investigation (with maps)
Number of pages:  11
Document Number Sequence:  12

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 Document  Date:   7/1/83
 Document  Type:   TDWR  correspondence
 Originator:
  •1g1nator-Aff1Hat1on:   TDWR
 ,^c1p1ent:   William J.  L1br1zz1, Director
 Recipient-Affiliation:   EPA Reg1on-VI
 Description:  Sample  analysis results from the Crystal City Airport
   abandoned  applicator  site
 Number  of pages:   2
 Document  Number  Sequence:  13
Document Date:   7/6/83
Document Type:   TDWR  Interoffice memo
Originator:  Henry Karnei, Jr.
Originator-Affiliation:  TDWR EQ Specialist D1st. 8
Recipient:  Gary Schroeder
Recipient-Affiliation:  TDWR Solid Waste and Spill Response Sec.
Description:  Chemical analysis of sampler collected at the abandoned
  aerial applicator site at CCA
Number of pages:  5
Document Number  Sequence:  14
Document Date:  7/15/83
Document Type:  TDWR Interoffice memo
 "Iglnator:  Dan McClellan
^Hglnator-Affi llatlon:  TDWR
Recipient:  Gary D. Schroeder
Recipient-Affiliation:  TDWR P. E. Chief
Description:  Immediate Removal Action for CCA abandoned aerial applicator
 site
Number of pages:  3
Document Number Sequence:  15
Document Date:  7/25/83
Document Type:  memo
Originator:  George A. Jones
Originator-Affiliation:  CDC
Recipient:  George Buynoskl
Recipient-Affiliation:  USEPA-publlc health advisor
Description:  recommend residential sampling
Number of pages:  1
Document Number Sequence:  16

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 Document  Date:   8/5/83
 Document  Type:   TDWR  Interoffice memo
 iVIglnator:   Henry  Karnel, Jr.
   1g1nator-Aff1l1at1on:   TDWR
-..eciplent:   Gary  Schroeder
 Recipient-Affiliation:   TDWR Solid Waste and Spill Response Sec
 Description   CC  Municipal Airport
 Number  of pages:  3
 Document.  Number  Sequence:  17
 Document Date:  8/12/83
 Document Type:  lab report
 Originator:  William Langley
 Originator-Affiliation:  USEPA GES-HL
 Recipient:  Charles Gazda
 Redplent-Affllluvion:  USEPA GES-E
 Description:  lab results
 Number of pages:  14
 Document Number Sequence:  18
Document Date:  8/19/83
Document Type:  lab report
Originator:  William Langley
Originator-Affiliation:  USEPA GES-HL
 >c1p1ent:  Charles Gazda
~ec1p1ent-Aff1l1at1on:  USEPA GES-E
Description:  lab results
Number of pages:  10
Document Number Sequence:  19
Document Date:  8/26/83
Document Type:  lab report
Originator:  William Langley
Originator-Affiliation:  USEPA GES-HL
Recipient:  Charles Gazda
Recipient-Affiliation:  USEPA GES-E
Description:  lab results
Number of Pages:  17
Document Number Sequence:  20

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 document Date:  8/26/83
  icument Type:  letter
. rlglnator:  James Turner
 Originator-Affiliation:  USCPA
 Recipient:  Jose Balderas
 Recipient-Affiliation:  Crystal City Manager
 Description:  threat to drlnklngwater
 Number of pages:  2
 Document Number Sequence:  21
Document Date:  9/1/83
Document Type:  EPA lab report
Originator:  William D. Langley
Originator-Affiliation:  Houston EPA office
Recipient:  Charles Gazda, Chief
Recipient-Affiliation:  Energency Response Branch
Description:  Transmlttal of laboratory report
Number of pages:  11
Document Number Sequence:  22
Document Date:  9/2/83
-Document Type: _communication record
 rlglnator:  David Price
>Hg1nator-AffIllation:  USEPA GAW-SE
Recipient:  Jose Balderas
Recipient-Affiliation:  Crystal City Manager
Description:  city cleanup assistance
Number of pages:  1
Document Number Sequence:  23
Document Date:  9/16/83
Document Type:  A1r and Waste Management Division
Originator:  Allyn M. Davis, Director
Originator-Affiliation:  A1r and Waste Management Division
Recipient:  Darwin C. Handel 1
Recipient-Affiliation:  Crystal Spraying Service
Description:  Crystal City, Texas Airport Site
Number of pages:  3
Document Number Sequence:  24

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Document Date:  9/23/83
  »cument Type:  TDWR telephone memo
 rlglnator:  DMI
Or1g1nator-Aff1Hat1on:  TDWR
Recipient:  Lopez
Recipient-Affiliation:  TDWR
Description:  Crystal City
Number of pages:  4
Document Number Sequence:  25
Document Date:  9/29/83
Document Type:  memo
Originator:
Originator-Affiliation:  TDWR
Recipient:  David Lopez
Recipient-Affiliation:  USEPA-Dallas
Description:  city unable to do cleanup
Number of pages:  1
Document Number Sequence:  26
Document Date:  10/1/83
Document Type:  photo package
 Vlglnator:  N/A
>1g1nator-Aff1Hat1on:  N/A
Recipient:  N/A
Recipient-Affiliation:  N/A
Description:  site photographs
Number of pages:  10
Document Number Sequence:  27
Document Date:  10/28/83
Document Type:  Superfund Enforcement Section
Originator:  Samuel L. Nott, Chief
Originator-Affiliation:  EPA
Recipient:  Clarence Sugarek
Recipient-Affiliation:   Dallas Pest Control
Description:  Crystal City, TV Airport Site
Number of pages:  1
Document Number Sequence:  28

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 Document Date:  4/21/83 - 11/2/83
 Document Type:  field notes
 Originator:  David Lopez
  •1g1nator-Aff1l1at1on:  City of Crystal City
 eclplent:  N/A
 Recipient-Affiliation:  N/A
 Description:  field notes
 Number of pages:  25
 Document Number Sequence:  29
Document Date:  11/9/83
Document Type:  TDWR Interoffice memo
Originator:  T1m WolteMnk
Or1g1nator-Aff111at1on:  Abandoned Site Response Unit
Recipient:  Dan McClellan
Recipient-Affiliation:  Spill Response Unit
Description:  meeting with City Manager
Number of pages:  2
Document Number Sequence:  30
Document Date:  1/12/84
Document Type:  memorandum
Originator:  Henry Karnel, Jr.
Dr1g1nator:Aff1l1atton:  USEPA
^•clplent:' Gary Schroeder
 .*c1p1ent-Aff1Hat1on:  TOUR
Description:  Inadequate clean-up of site by EPA
Number of pages:  4
Document Number Sequence:  31
Document Date:  3/6/84
Document Type:  memorandum
Originator:  Henry Karnel, Jr.
Originator-Affiliation:  USEPA
Recipient:  Gary Schroeder
Recipient-Affiliation:  TDWR
Description:  follow-up Inspection
Number of pages:  4
Document Number Sequence:  32

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Document Date:  3/13/84
Document Type:  memorandum
 V1ginator:  Dan McClellan
 r1g1nator-Aff1liat1on:  USEPA
Recipient:  Gary Schroeder
Recipient-Affiliation:  TDWR
Description:  Investigation of site
Number of pages:  2
Document Number Sequence:  33
Document Date:  3/29/84
Document Type:  request
Originator:
Or1g1nator-Aff111atlon:  10 point document
Recipient:
Recipient-Affiliation:
Description:  Immediate removal request
Number of pages:  20
Document Number Sequence:  34
Document Date:  4/4/84
Document Type:  memo
Originator:  Henry Karnel
^1g1nator:Aff1Hat1on:  TDWR
recipient:  Bryan D1xon
Recipient-Affiliation:  TDWR
Description:  results of samples
Number of pages:  1
Document Number Sequence:  35
Document Date:  4/12/84
Document Type:  memo
Originator:  William Langley
Originator-Affiliation:  USEPA
Recipient:  Phil Crocker
Recipient-Affiliation:  USEPA
Description:  data review from
Number of pages:  2
Document Number Sequence:  36
Texas Dept. .of Ag

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 Document  Date:   4/13/84
 ^cument  Type:   letter
 ylglnator:   Jose  Balderas
 Urlglnator-Aff1Hatlon:   Crystal City Manager
 Recipient:   Dick Whittlngton
 Recipient-Affiliation:   USEPA
 Description:   city clean-up assistance
 Number  of pages:   1
 Document  Number  Sequence:  37
 Document  Date:   4/13/84
 Document  Type:   memo
 Originator:   Henry  Karnel
 Originator-Affiliation:   TDWR
 Recipient:   Bryan D1xon
 Recipient-Affiliation:   TDWR
 Description:   additional  results  of  samples
 Number  of pages:  3
 Document  Number  Sequence:   38
 Document Date:   4/21/84
^Document Type:
Originator:  J.  Lucas
 
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 Document Date:   5/9/84
^Document Type:   letter
  -Iglnator:   Charles  Bond
  ,-lginator-Aff 111 at ion:   Weston-Sper
 Recipient:   Charles  Gazda
 Recipient-Affiliation:  ERB
 Description:   Emergency  Response  Summary
 Number of pages:   2
 Document Number  Sequence:  41
 Document  Date:   6/26/84
 Document  Type:   report
 Originator:
 Or1g1nator-Aff11iation:
 Recipient:
 Recipient-Affiliation:
 Description:  sampling for  pesticides
 Number  of pages:   4
 Document  Number  Sequence:   42
 Document  Date:   6/29/84
 Document  Type:   Action Report  7  Immediate  Removal  Action
 .Originator:   David  Lopez
 JVr1g1nator-Aff1l1at1on:   TWC
 Jecipient:   Samuel  Nott
"Recipient-Affiliation:  Chief  Superfund  Branch
 Description:  After Action  Report
 Number  of pages:  4
 Document  Number  Sequence:   43
Document  Date:   7/84
Document  Type:   report
Originator:   TACB
Originator-Affiliation:
Recipient:
Recipient-Affiliation:
Description:   sampling project  of  TDWR
Number of pages:   5
Document  Number  Sequence:   44

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 Document Date:  10/9/84
-Document Type:  news article
   •Iginator:  Owlght Sllverman
  Mg1nator-Aff 111at1on:  San Antonio Light
 Recipient:  public
 Recipient-Affiliation:  public
 Description:  toxic chemicals 1n landfill
 Number of pages: 1
 Document Number Sequence:  45
 Document Date:  10/10/84
 Document Type:  news article
 Originator:  Dwlght Sllverman
 Or1g1nator7Aff111at1on:   San Antonio Light
 Recipient:  public
 Recipient-Affiliation:   public
 Description:   toxic chemicals In landfill
 Number of pages:   1
 Document Number Sequence:  46
 Document Date:   11/6/84
 Document Type:   report
 Originator:   David Lopez
 Xr1g1nator-Aff1l1at1on:  USEPA (6ES-E)
  «dp1ent:   Rod Klmbro
 Recipient-Affiliation:  TDWR
 Description:  After Action Report
 Number of pages:   9
 Document Number Sequence:   47
 Document Date:   5/1/85
 Document Type:   memo
 Originator:   Dick Whittington
 Originator-Affiliation:   USEPA (6A)
 Recipient:'  Jack McGrawy
 Recipient-Affiliation:  USEPA (WI-562)
 Description:   Increase RI/FS  Study
 Number of pages:  1
 Document Number Sequence:   48

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 Document Date:   6/28/85
 Document Type:   letter
  ~1g1nator:  Jose Balderas
  •1g1nator-Aff1llatlon:  Crystal City Manager
 Keclplent:   Allyn Davis
 Recipient-Affiliation:  USEPA
 Description:  city participation 1n RI/FS
 Number of pages:  1
 Document Number  Sequence:  49
Document Date:   7/15/85
Document Type:   letter
Originator:  Robert Hannesschlager
Originator-Affiliation:  USCPA (6AW-S)
Recipient:' Bryan D1xon
Recipient-Affiliation:  TDSW
Description:  RI/FS Funds
Number of pages:  2
Document Number  Sequence:  50
Document Date:  7/16/85
Document Type:  report
Originator:  Charles Faulds
Rr1g1nator-Affiliation:  TDWR
"jedplent:  Bonnie Devos
Recipient-Affiliation:  USEPA
Description:  work scope and cost estimate
Number of pages:  32
Document Number Sequence:  51
Document Date:  7/17/85
Document Type:  letter
Originator:  Robert Hannesschlager
Originator-Affiliation:  USEPA
Recipient:  Jose Qalderas
Recipient-Affiliation:  Crystal City Manager
Description:  response to city offer of assistance
Number of pages:  2
Document Number Sequence:  52

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 Document  Date:   10/4/85
.Document  Type:   news release
   1g1nator:   Region 6 AP
 .  1g1nator-Aff1Hat1on:  USEPA
 Recipient:  General
 Recipient-Affiliation:  General
 Description:  site Information
 Number of pages:  2
 Document  Number  Sequence:  S3
Document Date:  11/5/85
Document Type:  letter
Originator:  Carlene Chambers
Or1gtnator:Aff1l1»t1on:  USEPA (6H-SS)
Recipient:' Charles Faulds
Recipient-Affiliation:  TDWR
Description:  comments on work scope
Number of pages:  3
Document Number Sequence:  54
Document Date:  12/4/85
Document Type:  letter
Originator:  Charles Faulds
>1g1nator:Af filiation:  TDWR
 £dp1ent:  Carlene Chambers
Rec1p1ent:Aff1Hat1on:  USEPA (6H-SS)
Description:  comments on work scope
Number of pages:  3
Document Number Sequence:  55
Document Date:  12/31/85
Document Type:  Texas Water Commission
Originator:  William E. Colbert Chief of Coummunlty Relations
Or1g1nator-Aff111at1on:  Hazardous Waste Management Division
Recipient:' Mr. Carlene Chambers
Recipient-Affiliation:  U. S. EPA Hazardous Waste Management Division
Description:  Crystal City Airport Superfund Site
Number of pages:   23
Document Number Sequence:  56

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Document Date:  1/7/86
Document Type:  report
 '-Iglnator:  Martyn Turner/Greg Tipple
  1g1nator-Aff1Hat1on:  TWC
Recipient:  N/A
Recipient-Affiliation:  N/A
Description:  work scope
Number of pages:  12
Document Number Sequence:  57
Document Date:  3/12/86
Document Type:  conference record
Originator:  M. Turner
Originator-Affiliation:  A. Onjanan
Recipient:  J1ra McGuIre
Rec1p1ent-Aff1 nation:  consultants
Description:  site visit
Number of pages:  2
Document Number Sequence:  58
Document Date:  3/19/86
Document Type:  letter
Originator:  Greg Tipple
^r1g1nator-Aff111at1on:  TWC
•edplent:  consultants
Kec1p1ent-Aff111at1on:  (same)
Description:  general questions/list of consultants
Number of pages:   9
Document Number Sequence:  59
Document Date:  4/10/86
U'jcuirint Type:  memo
Originator:  David Sorrells
Or1g1nator:Aff111at1on:  TWC
Recipient:  Larry Soward
Recipient-Affiliation:  TWC
Description:  Commission Fact Sheet
Number of pages:  2
Document Number Sequence:  60

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   cument  Date:   4/21/86
  jcument  Type:   report
 Originator:   Stanley  H1tt
 Originator-Affiliation:  U.S. EPA  - TRS
 Recipient:   Jose Balderas
 Reclplent^Aff111at1on:  Crystal City Manager
 Description:  Action  Summary
 Number  of pages:   2
 Document  Number  Sequence:   61
 Document  Date:   6/12/86
 Document  Type:   report
 Originator:  Martyn Turner
 Or1g1nator:Aff1Hat1on:  TWC
 Recipient:  J1m  McGuIre
 Recipient-Affiliation:  U.S. EPA
 Description:  Revision Field Sampling
 Number of pages:  2
 Document  Number  Sequence:  62
Document Date:  6/26/86
 jcument Type:  cost proposal
 Hglnator:  EBASCO
Or1g1nator-Affiliation:
Recipient:
Recipient-Affiliation:  USEPA
Description:  cost breakdowns
Number of pages:  26
Document Number Sequence:  63
Document Date:  6/30/86
Document Type:  contract
Originator:
Or1ginator-Aff1lat1on:  USEPA 7 EBASCO Services
Recipient:                                 .         .
Recipient-Affiliation:
Description:  contract for services for Crystal City Airport superfund
              site Investigation and feasibility study
Number of pages:  69
Document Number Sequence:  64

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 N>cument  Date:   7/11/86
  ocument  Type:   letter
 Originator:   Edward  Bates
 Or1g1nator-Aff1Hat1on:  EBASCO
 Recipient:   Martyn Turner
 Recipient-Affiliation:   TOUR
 Description:   clarify RI costs
 Number  of pages:  6
 Document  Number  Sequence:   65
 Document  Date:   7/21/86
 Document  Type:   letter
 Originator:   Martyn  Turner
 Originator-Affiliation:   TDWP
 Recipient:'  Ed  Bates
 Rec1p1ent-Aff111at1on:   envlrosphere
 Description:   proposed  amendment
 Number  of pages:   2
 Document  Number  Sequence:   66
 Document  Date:   8/1/86
•Document  Type:   letter
 ,r1g1nator:   Martyn  Turner
•Originator-Affiliation:   TDWR
 Recipient:'  Paul  S1em1nsk1
 Recipient-Affiliation:   USEPA
 Description:  Revised RI/FS Schedule
 Number  of pages:   2
 Document  Number  Sequence:  67
Document Date:   8/8/86
Document Type:   commentary
Originator:   Jim McGuIre
Or1g1nator:Aff1l1at1on:   USEPA  6H-ST
Recipient:  Joe  Brown
Recipient-Affiliation:  TDWR
Description:  workplan comments
Number of pages:   5
Document Number  Sequence:   68

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 Document  Date:   8/13/86
Document  Type:   memo
  •Iglnator:   E.  Heyer
 ^rlglnator-AfflHatlon:  TDWR, QAO
 Recipient:   Martyn  Turner
 Recipient-Affiliation:  TDWR
 Description:  comments on QAP;P
 Number of pages:  3
 Document  Number  Sequence:  69
Document Date:  8/21/86
Document Type:  letter
Originator:  TDWR
Originator-Affiliation:
Recipient:' Ed Bates
Recipient-Affiliation:  EBASCO
Description:  comments on draft plans
Number of  pages:   10
Document Number Sequence:  70
Document Date:  9/2/86
Document Type:  telecommunication
Originator:  Martyn Turner
 Ylg1nator-Aff1Hat1on:  TDWR
Recipient:' Ed Bates
Recipient-Affiliation:  EBASCO
Description:  EPA comments CCA QA/QC Plan
Number of pages:  10
Document Number Sequence:  71
Document Date:  9/2/Cf
Document Type:  letter
Originator:  Paul S1era1nsk1
Originator-Affiliation:  USEPA
Recipient:  David Sorrel Is
Recipient-Affiliation:  TWC
Description:  comments on QA/QP
Number of pages:  4
Document Number Sequence:  72

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Document Date:  9/5/86
  ^cument Type:  report
  Iglnator:  Ed Bates
originator-Affiliation:  EBASCO
Recipient:  Martyn Turner
Rec1p1ent:Aff1l1at1on:  TDWR
Description:  Revision Field Sampling Plan
Number of pages:  85
Document Number Sequence:  73
Document Date:  9/8/86
Document Type:  date managed plan
Originator:  EBASCO Services, Inc.
Or1g1nator-Aff1 11at*qn:  (same)                   ;   ..:
Recipient:  Texas Water Commission
Recipient-Affiliation:  EPA Region VI
Description:  Data Management Plan for Crystal City Airport Superfund
  Site
Number of pages:  25
Document Number Sequence:  74
Document Date:  9/17/86
"•ocument Type:  QA/QC Quality Control Plan
 .•Iglnator:  Sam Mason
Or1g1nator-Aff111at1on:  EBASCO
Recipient:' EPA RPM R-VI
Recipient-Affiliation:  EPA
Description:  general report
Number of pages:  81
Document Number Sequence:  75
Document Date:  9/17/8*
Document Type:  letter
Originator:  Bonnie Devos
Or1g1nator-AffIllation:  USEPA-SPS
Recipient:  Greg Tipple
Recipient-Affiliation:  TWC
Description:  conditions for approval to airport sampling plan
Number of pages:  3
Document Number Sequence:  76

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 Document  Date:   9/17/86
-Document  Type:   memo
   1g1nator:  E.  Heyer
 .r1g1nator-Aff1l1at1on:  QAO, TDWR
 Recipient:  Martyn Turner
 Recipient-Affiliation:  TDWR
 Description:  EPA comments on QAPjP
 Number of pages:  2
 Document  Number  Sequence:  77
Document Date:  9/17/86
Document Type:  letter
Originator:  Martyn Turner
Or1g1nator-Aff1Hat1on:  TDWR
Recipient:  Sam Mason
Rec1p1ent-Aff111at1on:  Envlrosphere
Description:  TWC comments
Number of pages:  4
Document Number Sequence:  78
Document Date:  9/23/86
Document Type:  letter
Originator:  David Sorrel Is
 >1g1nator-Aff1 Hatlon:  TDWR
recipient:  Bonnie Devos
Rec1p1ent:Aff1Hat1on:  USEPA
Description:  Revision Workplan Schedule
Number of pages:  3
Document Number Sequence:  79
Document Date:  9/2P/8C
Document Type:  letter
Originator:  Paul Sleinlnskl
Originator-Affiliation:  USEPA
Recipient:' Greg Tipple
Recipient-Affiliation:  TWC
Description:  revisions to QAPJP
Number of pages:  2
Document Number Sequence:  80

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 document Date:  10/1/86
   cument Type:  letter
   1g1nator:  Edward Bates
 Originator-Affiliation:  Envlrosphere
 Recipient:   Martyn Turner
 Recipient-Affiliation:  TOWR
 Description:  revised page 60 QA/QC  plan
 Number of pages:   2
 Document Number Sequence:  81
 Document Date:   10/17/86
 Document Type:   Interoffice memo
 Originator:   John Dupont
 Or1g1nator-Aff111at1on:   Texas Water Commission
 Recipient   Martyn Turner
 Recipient-Affiliation:   H & SW D1v., EPA
 Description:  Qaullty Assurance Inspection  at  EBASCO  Mobile  Laboratory
 Number of pages:   2
 Document Number  Sequence:  82                                        i
 Document Date:   10/22/86
 Document Type:   memo
  -Iglnator:   Geol  Pettlgrew for  Carl  S.  Hlckam/Sr.  Public  Health  Advisor
  /1g1nator-Aff111at1on:   Dept. of  Health &  Human  Services
"Recipient:   Jim McGuire
 Recipient-Affiliation:   Texas Remedial  Section
 Description:   Proposed  Action Level  of  Crystal  City Airport  Superfund
   Site
 Number of pages:   1
 Document Number Sequence:   83
 Document Date:   10/23/86
 Document Type:   memo
 Originator:   Jim McGuire,  Project  Manager
 Originator-Affiliation:   Texas  Remedial  Section
 Recipient:   Paul S1em1nsk1,  Project  Officer
 Recipient-Affiliation:   EPA  State  Programs  Section
 Description:   Field Audit  of Sample  Collection  at the  Crystal  City  Airport
   Superfund  Site
 Number of pages:  2
 Document Number Sequence:  84

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 Document  Date:   10/29/86
 Document  Type:   memo
-Originator:   John  Dunont, Quality Assurance  Inspector, Field Operations
   Division
   1g1nator-Aff111at1on:  Texas Water Commission
 Recipient:   Martyn  Turner
 Recipient-Affiliation:  H 4 SW D1v.t EPA
 Description:  Quality Assurance  Inspection at Hlttman-EBASCO Laboratory
 Number  of pages:   2
 Document  Number  Sequence:  85
 Document Date:   11/6/86
 Document Type:   memo
 Originator:  Sam Mason, P.E.. Site Manager
 Or1g1nator-Affiliation:  EBASCO Services, Inc.
 Recipient:   Martyn  Turner
 Recipient-Affiliation:  EPA-Texas Water Commission
 Description:   Plan  for Disposal of Liquids - Crystal City Airport
   Investigation  Crystal CHy, Texas
 Number of pages:  2
 Document Number  Sequence:  86
Document Date:   12/4/86
Document Type:   newspaper article
"">1g1nator:  Zavala Co. Sentinel
 >1gtnator-Aff1l1at1on:  Crystal City, Texas
"Recipient:  public
Recipient-Affiliation:
Description:  contamination still studied
Number of pages:  1
Document Number  Sequence:  87
Document Date:  1/20/87
Document Type:  letter
Originator:  Edward Bates
Originator-Affiliation:  EBASCO
Recipient:  Martyn Turner
Recipient-Affiliation:  TWC
Description:  fluid disposition
Number of pages:  2
Document Number Sequence:  88

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Document Date:   1/27/87
nocument Type:   contract amendment
   Iglnator:  Edward Bates
  .-1g1nator-Aff1l1at1on:  EBASCO
Recipient:  Martyn Turner
Recipient-Affiliation:  TWC
Description:  contract #14-60042-2
Number of pages:  13
Document Number  Sequence:  89
Document Date:  2/4/87
Document Type:  table
Originator:  Sam Mason
Originator-Affiliation:  EBASCO
Recipient:' Martyn Turner
Recipient-Affiliation:  TWC
Description:  response objectives
Number of pages:  2
Document Number Sequence:  90
Document Date:  2/13/87
Document Type:  contract amendment
.Originator:  Larry Soward
  -1g1nator-Aff111at1on:  TWC
 &c1p1ent:  Edward Hlopak
Recipient-Affiliation:  EBASCO
Description:  contract #14-60042-2
Number of pages:  21
Document Number Sequence:  91
Document Date:  2/19/87
Document Type:  letter
Originator:  Edward Bates
Or1g1nator-Aff1l1at1on:  EBASCO
Recipient:' Martyn Turner
Recipient-Affiliation:  TWC
Description:  revision to QA/QC Plan
Number of pages:  2
Document Number Sequence:  92

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Document  Date:   2/20/87
  vcument  Type:   letter
   Iglnator:   J1m McGuire
 Ur1g1nator-Aff1l1at1on:   USEPA
 Recipient:   Martyn  Turner
 Recipient-Affiliation:  TWC
 Description:  disposal of liquids
 Number  of pages:  2
 Document  Number  Sequence:  93
 Document  Date:   3/20/87
 Document  Type:   conference  record
 Originator:   Martyn  Turner
 Originator-Affiliation:   Sam Mason, Rod Klmbro, Lorlng Pitts, T1m
   Wolternlk,  Jim McGuire, Stan Hltt, Martyn Turner, Greg Tipple
 Recipient:  same as  above
 Recipient-Affiliation:   same as above
 Description:  conference  Per1-R1sk Assessment
 Number of pages:   11
 Document  Number  Sequence:   94
Document Date:  4/1/87
T^cument Type:  conference record
: iMglnator:  Martyn Turner
"Ur1g1nator:Aff1l1at1on:  TWC
Recipient:' George Pettlgrew, Carl Hlckam, Stan Hltt, J1m McGuire, Sam
  Mason, Lorlng Ptts, martyn Turner, Greg Tipple
Recipient-Affiliation:  same as above
Description:  Risk Assessment Comments
Number of pages:  1
Document Number Sequence:  95
Document Date:  4/10/87
Document Type:  letter
Originator:  Stanley H1tt
Originator-Affiliation:  USEPA-TR5
Recipient:  Greg Tipple
Recipient-Affiliation:  TWC
Description:  summary of risk assessment
Number of pages:  2
Document Number Sequence:  96

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Document Date:  4/13/87
  cument Type:  letter
 Hglnator:  E. C. Bates
Originator-Aff1 Hatlon:  Envlro sphere
Recipient:  Martyn Turner
Recipient-Affiliation:  TWC
Description:  alternative evaluation
Number of pages:  9
Document Number Sequence:  97
Document Date:  4/15/87
Document Type:  tabel
Originator:  EBASCO Atlanta
Orlglnato^Affl 11at1on:  same as above
Recipient:' general
Recipient-Affiliation:  same as above
Description:  parameters and definitions • cancer risk
Number of pages:  9
Document Number Sequence:  98
Document Date:  4/16/87
Document Type:  conference record
' Mglnator:  Martyn Turner
 *1g1nator-Aff1l1at1on:  TWC
Recipient:  Greg Tipple, Sam Mason, J1m McGuIre
Recipient-Affiliation:  same as above
Description:  FSRA - Final Alternative Comments
Number of pages:  1
Document Number Sequence:  99
Document Date:  4/24/87
Document .Type:  memo
Originator:  J1m McGuIre
Originator-Affiliation:  USEPA (6H-ST)
Recipient:  Martyn Turner, Greg Tipple, Sam Mason
Recipient-Affiliation:  same as above
Description:  Potential Remedial  Alternatives
Number of pages:  2
Document Number Sequences:  100

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 Document Date:   6/87
 Document Type:;  RI  Final  Report
 -Originator:   EBASCO Services,  Inc.
   1g1nator-Aff11iatlon:   (same)
  ddpient:   Texas Water  Commission
 Rec1p1ent-Aff111a1ton:   EPA Region  VI
 Description:   Remedial  Investigation Final  Report
 Number of pages:   156
 Document Number  Sequence:   101
 Document  Date:   6/87
 Document  Type:   Final  Report  RI
 Originator:   EBASCO Services,  Inc.
 Originator-Affiliation:   (same)
 Recipient:'  Texas'Water  Commission
 Recipient-Affiliation:   EPA Region  VI
 Description:  RI Appendix
 Number  of pages:   202
 Document  Number  Sequence:   102
 Document  Date:   7/87
 Document  Type:   feasibility  study
 Originator:   EBASCO Services,  Inc.
-Originator-Affiliation:   (same)
  *cipient:   Texas  Water  Commission
_sc1p1ent-Aff1Hat1on:   EPA  Region  VI
 Description:  Final Report
 Number  of pages:   334
 Document  Number  Sequence:  103
 Document  Date:   7/24/87
 Document  Type:   news  release
 Originator:   USEPA
 6r1g1nator-Aff1Hat1on:   USEPA
 Recipient:   general public
 Recipient-Affiliation:   general public
 Description:  EPA Environmental News
 Number  of pages:  2
 Document  Number  Sequence:   104

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ATTACHMENT B

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Crystal City Airport Site
Crystal City, 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 concern raised during the remedial planning activities
            at the Crystal City Airport Superfund site.

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

I.  Background on Community Involvement

    In early 1982 a local fanner filed suit against Franks Crop Ousting
    Service alledging that a pesticide sprayed by Frank's drifted onto
    his pecan grove and killed his pecan trees.  The fanner won his       ?
    suit and the crop dusting operation went out of business.             =
                                                                          k
    The Texas Department of Water Resources  (now the TWC) requested
    funds from EPA in October 1983 to mitigate the immediate hazards at the
    site.  Contaminated soil and some 75 drums were removed and placed
    in trenches.   Clean soil was used to backfill and grade.  In 1984 a
    fence was installed and caution signs were posted.

    On October 29, 1984, a meeting was held at the Crystal City Library
    to brief the public and city officials about the studies to be
    conducted at the site.  Approximately 25 people attended the
    briefing conducted by the TWC and EPA.

    The people of Crystal City, Texas learned via an EPA news release on
    October 4, 1985, that the TWC had received funds to conduct studies
    at the airport site.  On September 9, 1986, TWC staff made a presentation
    to the Mayor and city council members regarding the upcoming studies  at
    the site.

    On the afternoon of August 20, 1987, representatives of TWC and EPA
    met with the Mayor, City Manager, Assistant Superintendent of
    Schools and other civic leaders.  Twenty-four people attended the
    meeting.  The results of the studies were discussed along with the
    various remedial alternatives.  That evening the TWC and EPA conducted
    a public meeting to brief the citizens about the study results; review
    the remedial alternatives considered; describe EPA's preferred remedy
    and, answered questions and comments.  45 people attended this meeting.

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    Eseguiel Guzman requested, on behalf of the Mayor and other civic
    leaders, that EPA extend the public comment period.  A two-week
    extension was granted changing the closing date to September 14, 1987.
    This decision was announced to the public via a news release on
    September 2, 1987.

    Following the extended comment period, a community meeting was held
    on September 21, 1987, to answer additional questions regarding the
    Remedial Alternatives.  During this meeting, several people supported
    incineration of the contaminants.  Approximately 50 people attended
    this meeting.

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

    The public comment period on the Feasibility Study for the Crystal
    City Airport Superfund site opened August 10, 1987 and closed
    September 14, 1987.  A public meeting was held August 20, 1987, in
    Crystal City, Texas with approximately 45 people in attendance,  a
    summary of the comment provided during the comment period is
    provided below.

Comment tl

EPA's proposed remedy of consolidating and capping, waste at the Crystal City
Airport site "... does not meet the requirements established by Congress
in the Superfund Amendments and Reauthorization Act of 1986  (SARA).11

EPA Response to Comment tl

The consolidation/capping remedy was proposed due to the unique nature of
contamination at this site, because it fulfilled all legal requirements,
and best conforms with SARA's remedy selection criteria.  In proposing
this remedy, full attention was given to Section 121(b)(1) of SARA.

The law clearly requires a preference for alternative treatment
technologies, but it does not mandate their use where they would be
inappropriate.  The proposed remedy's conformance with the preference of
the law is provided in the following responses.

Comment 12

The proposed consolidation-capping remedy'is a "substandard/second class"
remedy for the site.  Explain EPA's justification for recommending a
remedy which does not treat waste to significantly reduce the mobility,
toxicity or volume of the contaminants.

EPA Response to Comment 12

The remedy proposed by EPA would be fully protective of human health and the
environment, consistent with the SARA and in no way would be a "second
class" cleanup.  The Remedial Investigation report found that, due to the

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alkaline makeup of of the soil, the organic pesticides and arsenic compounds
have been adsorbed to the soils.  Furthermore, because the onsite soils
have low permeability and there is no groundwater other than that which
percolates from the surface, the potential for further migration of waste
is extremely remote.  Further trying to immobilize the waste is not practicable
since the contaminants are effectively immobilized and isolated.  The
organic compounds will continue to degrade under the
cap into less toxic compounds, however, significant reductions in toxicity
were not claimed for this remedy.  Finally, because the contaminants
represent less than one-tenth of a percent of the volume of the soil,
none of the demonstrated alternatives, including a standard incineration
unit, could be expected to achieve a significant reduction in volume.

Comment 13

How does the proposed consolidation remedy comply with the minimum tech-
nology requirements for land disposal facilities including the land disposal
ban?

EPA Response to Comment #3

RCRA is not considered to be applicable as it pertains to the proposed    :
remedy, although some of PCRA's provisions; such as cap design, are considered
relevant and appropriate.  For the RCRA minimum technology requirements
for landfills (40 CFR 264 Subpart N) to be applicable/ disposal or management
of waste must occur.  The proposed remedy is not considered a disposal
action since the contaminated material will be consolidated in the unit
or area of contamination from which they originated.  A multi-layered cap
(RCRA equivalent) while not an applicable requirement, is considered
relevant and appropriate for the overall effectiveness of the remedy;
therefore, a RCRA cap will be placed over the consolidation cell.  The
cap will remove the potential of future infiltration as well as remove
the direct contact threat posed by the currently exposed waste.

Comment #4

Is reburial of contaminated soil considered a permanent solution even
after the 30-year maintenance period has ended?

EPA Response to Comment #4

Yes.  The Remedial Investigation found that the arsenic and organic
pesticides spilled at the site have been locked into the top foot of the
alkaline soils at the site.  The degree that contaminants are bound up is
of the same degree that would have been achieved if the pure contaminants
had been processed by a solidification technology.  Consolidating this
"naturally treated" waste under a hazardous waste cap is therefore
considered permanent.   The 30-year maintenance period mentioned in the
Feasibility Study is used to calculate operation and maintenance costs
for each remedy; it does not imply that the effectiveness of the cap
would cease at the end of that time.

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Comment #5

Was the recommendation for the consolidation remedy based on  the  low
population of the area surrounding the airport site?

EPA Response to Comment #5

No.  A site specific risk assessment was conducted in order to develop
the health based clean-up criteria for the site.  The assessment  considered
the nearest possible receptor  (residents of nearby housing project)  as
the worst case exposure scenario.  The actual number of people which
could be potentially exposed is not a factor in the assessment, but
rather the distance to the nearest receptor within the total  number  of
potentially exposed people.  Although the density of the population  is
not a factor in developing a cleanup level; the location of the population
relative to the site is a factor in determining the feasibility of
various alternatives.

Comment 16

Has the location of the consolidation cell already been determined?     .  :
                                                                          t
EPA Response to Comment #6                                                •.

No.  The location.of the consolidation cell will be determined during
the design phase of the project.  The Agency will discuss potential
locations with the city management during the design.

Comment #7

The Agency's own Feasibility Study contradicts the rationale  used for
proposing the consolidation remedy.

EPA Response to Comment 17

The intent of the statements in Section 4 of the Feasibility  Study
regarding the reduction of mobility, toxicity or volume was not to
suggest non-compliance with the requirements of SARA.  As previously
stated, Section 121(b)(1) of SARA prefers the selection of actions which
significantly reduce mobility, toxicity or volume; however, it is not a
requirement of the provision.  The statement made regarding Section
121(b)(1) serves only to show how each remedy meets the preference of
SARA, relative to the other remedies.  In no case did any of  the
demonstrated alternatives significantly reduce mobility, toxicity or
volume; therefore, all remedies, with the exception  of no action, are
considered equally protective.

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To clarify EPA's position on the proposed remedy, copies of the draft
Sumnary of Remedial Alternative Selection for the site, together with the
Remedial Investigation and Feasibility Study, were made available at the
information repositories at the start of the public comment period.
This draft document represents the Agency's synthesis of site studies,
and contains the rationale for EPA's proposed remedy.  While not a final
document, the draft Summary of Remedial Alternative Selection is less
ambiguous about the conformance of the proposed remedy with SARA.
Comments and questions received during the public comment period are used
to further clarify the basis for EPA's proposed remedy, or another
remedy, should the proposed plan be found to be inappropriate.

Comment #8

What activities is EPA conducting to prevent future contamination of
airports due to crop dusting operations?

EPA Response to Comment 18

The Agency has imposed stringent requirement which regulate the use of
and disposal of chemicals used by industry including the aerial
applicating industry.  In the State of Texas, funds have been provided    ;
for limited soil sampling at airports which appear to pose a public       :
health threat.  Based on the results of the sampling, the sites could     w
be included on future priority lists for the Superfund.

Comment #9

Why was incineration not chosen as EPA's preferred remedy for the
Crystal City Airport site?

EPA Response to Comment 19

This alternative remedy did not conform with the Superfund statute
as well as the consolidation/capping remedy.  Incineration would remove
the organic contaminants from the soil; however, the most toxic contaminant,
arsenic, would continue to be present in the residual ash/soil following
treatment.  The reduction in volume would be, at best, minimal since the
waste makes up only a small percentage of the contaminated soil.  Using
currently available and demonstrated incineration systems, the arsenic
would remain in the scorched earth, or scrubber sludges, and would
require storage as hazardous waste.

Comment 310

Several people were concerned that health monitoring was not conducted
during the recent remedial investigation and requested this occur in
the near future.

EPA Response to Comment IIP

Health monitoring was not conducted due to the lack of any documented
health problem relating to the contaminants at the site.  Should
evidence of health related problems exist, the information should be
submitted to the Texas Department of Health for further action.

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