PB96-963916
                                 EPA/ROD/R03-96/237
                                 March 1997
EPA  Superfund
       Record of Decision:
       Middletown Airfield Site,
       Operable Unit 3, Middletown, PA
        9/17/1996

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DECLARATION
RECORD OF DECISION FOR MIDDLETOWN AIRFIELD
REMEDIAL ALTERNATIVE SELECTION

SITE NAME AND LOCATION

Middletown Airfield Site
Middletown, Pennsylvania

STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected final remedial action for the Middletown
Airfield Site (Site), in Middletown, Pennsylvania, chosen in accordance with the
Comprehensive Environmental Response, Compensation and Liability Act of 1980
(CERCLA), as amended, and to  the extent practicable, the National Contingency Plan
(NCP), 40 CFR 300. This decision is based on this site's administrative record file.

The Commonwealth of Pennsylvania has concurred with the selected remedy.

DESCRIPTION OF THE SELECTED REMEDY

Based on the results of the risk assessment (RA) conducted as part of the operable
unit (OU) three investigation, it is concluded that the conditions at the Site, as
controlled by the RODs for OU1  and OU2 and the ESD, pose no current or potential
threat to human health or the environment and no additional remedial actions need  to
be implemented.  Although potentially hazardous constituents are present in Site
ground water, measures, that are compliant with applicable or relevant and
appropriate requirements (ARARs)  [more fully described in the 1987 Record of
Decision (ROD), the 1990 ROD and the 1992 Explanation of Significant Differences
(ESD)], are already being taken to  remedy that condition.  All of the requirements
outlined in the 1987 ROD and the 1990 ROD (as modified by the 1992 ESD),  will
remain in effect.  Consequently, the Site satisfies the requirements for a "No Further
Action" decision.

The ongoing nature of the previous remedial actions have been taken into account
prior to selecting the "No Further Action" decision for this operable unit.

DECLARATION STATEMENT

It has been determined that no significant risk or threat to  human health or the
environment exists from exposure to current conditions at this Site. Therefore, no
additional action is necessary to provide adequate protection to human health and
the environment.
Thomas C. Voltaggje; ^^                      Date
Division Director
Hazardous Waste Management Division

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                               Record of Deci'sion for OU#3:
                             Middletown Air Reid,
                                      Middletown, PA
Site Name. Location, and Description

       This is the Record of Decision (ROD)
for Operable Unit #3, which addresses actions
required by the ROD for Operable Unit #2
issued in 1990, as modified by the 1992
Explanation of Significant Differences (ESD) for
the Middletown Air Reid NPL Site (Site).  The
Site is located in Dauphin County,
Pennsylvania, about 8 miles southeast of
Harrisburg. It is situated between the
boroughs of Highspire and Middletown along
Pennsylvania Route 230. and bordered by the
Susquehanna River to the south (Figure).

       Pursuant to an Administrative Order on
Consent for Operable Unit #2 issued by the
United States Environmental Protection Agency
(EPA), Region III,  and executed by the United
States Air Force (USAF), effective September 8,
1993, a Supplemental Studies Investigation
(SSI) was conducted at the Middletown Air
Reid Site (Site), also known as the Harrisburg
International Airport, Middletown, Pennsylvania.
The United States Army Corps of Engineers
(USAGE), Omaha District, acting as service
support agency for the USAF, contracted with
ERM Program Management Company (ERM) to
conduct the SSI at the Site and prepare a
Focused Feasibility Study (FFS) report based
on the data collected during the SSI. The FFS
summarized current conditions at the Site and
included a discussion of the work completed
and results obtained from the SSI performed at
the Site.  The report also presented the results
of a baseline risk  assessment  (RA) and
evaluated the need for remedial action based
on all the data collected during the SSI as well
as data from a parallel study undertaken by the
Pennsylvania Department of Transportation
(PADOT) Bureau of Aviation.

This Site lies within the Triassic Lowland of the
Piedmont Physiographic Province. The Triassic
Lowland is characterized by a gentry undulating
topography, which slopes  generally to the
south and is  traversed by long low ridges and
a few round hills. Altitudes on the site range
from 280 feet above mean sea level (MSL) at
the Susquehanna River to approximately 420
feet MSL at the northern boundary.

Very little of the site is an undisturbed natural
area because of industrial/ commercial land
uses. Site topography provides a significant
portion of the driving force behind groundwater
movement at the site. Groundwater
withdrawals from several pumping centers also
strongly influence groundwater flow at the site.
On the basis of groundwater usage, the
subsurface at the Middletown Airfield Site can
be divided into three broad categories:
overburden, shallow bedrock, and the deep
bedrock. Usage of the deep bedrock
groundwater (greater than 200 feet) is
extensive. Usage of the shallow bedrock
groundwater is less extensive, while
groundwater hi the  overburden is not used as a
direct water supply  source.

Highlights of Community Participation

       EPA has issued the FFS and Proposed
Plan as part of its public participation
responsibilities under §117(a)  of the
Comprehensive Environmental Response,
Compensation and  Liability Act of 1980
(CERCLA), commonly referred to as
"Superfund", as amended by the Superfund
Amendments and Reauthorization Act  of 1988
(SARA) and to the extent possible, the National
Oil and Hazardous Substances Pollution
Contingency Plan (NCP, 40 CFR 300)  on
August 1, 1996.  The Proposed Plan
summarized information which is found in
greater detail in the 1996 FFS and other
documents contained in the Administrative
Record. A public comment period for the
Proposed Plan was held from August 1,  1996
through August 30,  1996. No comments were .
received during this period.

       The U.S. Environmental Protection
Agency (EPA) is the lead agency for this Site.

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                                         aenetai&d
            Base Msp
MMefetMm AfefMd m Sit*
This ROD identifies the option selected by EPA
for remediating the Site based upon trie
Administrative Record, which includes the
findings of GIB FFS and the Proposed Plan.
The selected remediation alternative, chosen in
accordance with CERCLA. as amended by
SARA and, to the extent practicable, the NCP,
provides for no additional action

Site History, and Enforcement Activities

       The property was initially established
Camp George Gordon Meade by the Army on
rolling farmland aa a basic training camp in
response to the Spanish-American War in July,
1898. In less than a year, the tent camp
reverted to a pickle farm operated by H. J.
Heinz Company until May 15,1917 when
ground was broken for what eventually became
known as the Olmsted Air Force Base in
September 1947.  Activities throughout the
history of the Site included:

       • warehousing and supply of parts,
                 equipment, general supplies,
                 petroleum, oil and lubricants (POL) for
                 the Northeast Procurement District;

                 • complete aircraft overhaul including
                 stripping, repainting, engine overhaul,
                 reassembly, and equipment
                 replacement

                 • engine and aircraft testing; and

                 • genera) base support maintenance
                 and operation.

                 The Air Force field and most of the Air
          Force industrial buildings (approximately 625
          acres) are currently owned by PAOOT which
          maintains and manages the Harhsburg
          International Airport (HIA) and the Pennsylvania
          Air National Guard.  HIA conducts general
          airport on^rations and maintenance, and leases
          buildings '.o fixed base operators and industrial
          tenants. Operations performed by tenants at
          this Site include:

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        •aircraft maintenance operations,
        aircraft paint stripping and repainting,
        and parts cleaning,

        •aircraft instrument overhaul and repair,

        •fabric dying,

        •machine shop operations,

        •typewriter ribbon inking and cartridge
        assembly.

        Approximately 218 acres of former
administrative and  housing facilities north of
Route 230 are owned by the Harrisburg
Campus of the Pennsylvania State University.
An additional 93  acres of former Air Force
warehouse facilities just south of the
Pennsylvania Turnpike (I-76) were sold to Rrst
Industrial Realty Trust, Inc. in 1995 by Fruehauf
Industries, which still retains ownership of the
North Base Landfill. Fruehauf was involved in
the manufacturing of truck trailers with Site
activities including  welding,  punching,
fastening,  foaming  and  painting.

        Studies have been conducted at the
facility since 1983 to investigate and monitor
areas that were affected by operations at the
Site. In March 1983, the volatile organic
compound (VOC) trichloroethylene (TCE) was
discovered in six of ten HIA production wells
which triggered subsequent environmental
investigations and studies, and the installation
of a water treatment system that is currently still
in use at the facility.

        In 1984, ground penetrating radar and
magnetometer surveys were conducted  by Roy
F. Weston, Inc. at the Runway, Industrial, and
North Base Landfill areas. Nine partially
exposed 55-gallon  drums were removed from a
fill area located along a stream bank northeast
of the Meade Heights housing complex. The
drums were empty except for water and
coatings of a hard, black tarry substance.
These contents were sampled and found to be
nonhazardous under the EPA characteristic of
EP toxicity.
        The Site was proposed for inclusion on
the National Priorities List (NPL) on October 1,
1984 after EPA scored the Site using the
Hazard Ranking System.  The Site was
included on the NPL on June 1, 1986.  EPA's
initial response centered around the  presence
of VOCs that were found in the groundwater
beneath the site.  The remedy selected to
address the contaminated drinking water
supply consisted of the installation of an air
stripping system for the removal of VOCs to
meet the drinking water standards. The
existing treatment system consists of two air
strippers, an ion exchange unit for the removal
of hardness, and disinfection prior to
distribution.  The selected  remedy was
documented in the December 30, 1987 ROD.

        In order to fully characterize  the site
and identify potential public health and
environmental  concerns, EPA issued  a contract
for an extensive study of the site in 1988.  The
study was conducted by NUS Corporation
(NUS) and Gannett Reming, Inc.  (GF).  The
study was performed in two phases-the
Remedial Investigation (Rl) and the Feasibility
Study (FS).

        Based  upon the 1988 study for the
Site, Operable Unit 2 Record of Decision (1990
ROD), signed on December 17, 1990 involved
continued operation of the existing drinking
water supply treatment systems and  the current
distribution system, the institution of
groundwater use restrictions, and additional
monitoring of the water supply wells.  The
remedy contained in the 1990 ROD also
involved the use of institutional controls to
address direct  contact and other threats from
potentially contaminated soils that may be
exposed at the Site during construction,
demolition, excavation or other activities that
disturb Site soils and involve the potential for
worker and public exposure to presently
contaminated soils.

       A train  spill occurred northwest of the
runway area on June 4, 1988, approximately
500 feet west of Production 'Well HIA-12.
Diethylene glycol and mineral oil were released
as a result of the spill.  Remediation at the site

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of the spill included pumping ground water into
settling tanks where skimming the mineral oil,
biotreatment of the diethylene glycol, and
reinjection of the treated water occurred.
Remediation was completed in 1989.

       In 1992, an ESD was issued to expand
the scope of the SSI, required by the 1990
ROD, and to explain that the ground water
remedy in the 1990 ROD was an Interim action
and the final decision would follow in the final
ROD issued after the SSI was completed.

       A potentially responsible party (PRP)
search was conducted in 1988 by EPA's
contractor Development Planning and
Research Associates, Inc. (DPRA).  DPRA
conducted its research within the information
collection guidelines as specified by EPA under
the terms of CERCLA, as amended by SARA.
The work was conducted in two phases.  The
first phase consisted of describing the Site and
remedial  activities; a title search and the
identification of possible PRPs; and making
recommendations for preparing  and sending
CERCLA  104(e) letters. The second phase
consisted of analyzing EPA's requests for
information letters issued to parties associated
with the Site pursuant to CERCIA Section
I04(e), and concluding the PRP search by
making appropriate recommendations. Based
Upon the recommendations and additional
followup information, EPA identified several
PRPs for  the contamination at the Site.

Scope and Role of Operable Unit

       The SSI satisfies the requirements of
the 1990  ROD and the 1992 ESQ.

       A December 1987 ROD was previously
issued for this Site for the protection of the
drinking water supply  in the area.  The ROD
outlined an interim remedy which focused on
the drinking water  supply as an  operable unit.
The ROD remedy consisted of providing a
potable water supply to those served by  the
HIA water system.  A central air stripping tower
and treatment plant was constructed for this
purpose.
       A second ROD was issued for the Site
in 1990. Five major study areas (SAs). were
designated.

• SA-1  Industrial Area • Includes HIA Ground
  Water Production Wells  and Runway Area
• SA-2  Industrial Area - Soils
• SA-3  Fire Training Area • Soils
• SA-4  North Base Landfill Area • Ground
  Water
• SA-5  Meade Heights Area • Surface
  Water

       The 1990 ROD addressed final
remedial actions at SAs 1,2, 3, and 4 and an
interim action at SA-5, since the field
investigation results at SA-5 were inconclusive
in determining contaminant sources and their
potential environmental impact.

       Under the 1990 ROD, the remedy
selection for SA-1 was the continued operation
of the ground water treatment system currently
in place at the Site, the institution of restrictions
for all ground water use throughout the Site
(which extends from the North Base Landfill to
the Susquehanna River), and the addition of
monitoring for the water supply wells.

       The remedy for SA-2 and SA-3
included land use and access restrictions, and
the development of public and worker health
and safety requirements for activities involving
construction, demolition, and excavation ar
other activities that would disturb the Sii* soil.

       The remedy for SA-4. which provides
protection of well MID-04, from contaminants
found in the North Base Landfill, was coupled
with the remedy for SA-1 to efficiently and
effectively address ground water contamination
at the Site.

       The interim action  required for SA-5
included a study evaluating the water quality
and organisms living In the stream near Meade
Heights.

       The SSI was required by the EPA's
December 1990 ROD. as clarified by the  April
1992 Explanation of Significant Differences
                                                                           AR300I36

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 (ESD).  After reviewing the 1990 ROD, the
 Pennsylvania Department of Environmental
 Resources (PADER) asserted that the ROD did
 not fully investigate the relationship between
 soil and ground water contamination, nor did it
 consider active soil cleanup technologies. The
 EPA incorporated PADEP concerns into the
 1992 ESD document.  The ESD explained that
 the ground water remedy selected in the ROD
 was an  interim action and that the final decision
 would follow in the ROD to be issued after the
 SSI was complete. The ESD also stated that
 the requirement, in the 1990 ROD, that the
 existing water supply system must continue to
 operate even if airport operations cease would
 be eliminated and reevaluated at a later date.

        Therefore the SSI satisfies the
 requirements of the 1990 ROD and the 1992
 ESD.
Summary of Site Characteristics

Industrial Area

       In the Industrial Area (which includes
the airports main pipeline distribution system,
the runway, and lagoons), polyaromatic
hydrocarbons (PAHs), low levels of VOCs, and
inorganics were determined to be scattered
throughout the area.

       PAHs occur uniformly throughout the
Site in relatively similar concentrations. Based
upon  published research, the presence of
PAHs at the concentrations detected at this
Site are common to developed areas
throughout the world.  Their presence is likely
due to normal industrial/commercial operations
such as asphalt, road and runway runoff, jet
exhaust and power plant emissions from
Crawford Station which is directly east of the
Site.

       TCE was found in 13 of 200 soil
samples above EPA's leaching screening level
of 0.2 parts per billion (ppb). In addition, the
TCE was located only at a single depth
suggesting that it is not migrating.  Low levels
of 1,2-dichloroethene (DCE) were found in 7 of
 200 samples and vinyl chloride was found in 2
 of 200 samples. Like TCE, there does not
 appear to be a discrete source for these
 contaminants,  nor do they appear to be
 migrating.

       The inorganics were generally detected
 at levels which are consistent with naturally
 occurring or background levels in soils.

       PAHs,  barium, chromium and nickel
 exceeded EPA's risk-based  concentration
 (RBC) soil screening levels,  developed by EPA
 Region III.  However, all of these contaminants,
 except for nickel in one sample, are below the
 Maximum Contaminant Levels (MCLs) in the
 ground water.  While nickel exceeded the MCL
 in one sample, it should be noted that it is not
 a contaminant  associated with Site operations
 as discussed in the 1990 Feasibility Study for
 operable unit two, which is a part of the
 Administrative  Record; and likely reflects an
 elevated natural background condition.

       The primary constituent of concern in,
 the ground water at the Site is TCE  Out of
 110 samples in the Industrial Area, TCE was
 detected above the MCL (5 ppb) in 70
 samples, with concentrations ranging from 6
 ppb to 1,000 ppb. Several other contaminants,
 such as tetrachloroethylene, vinyl chloride, and
 DCE, were detected above MCLs, however
 they were in fewer than 5% of the samples.

       Results of the screening  analysis
 indicated that a number of constituents,
 including PAHs, pesticides, and inorganics
frequently exceeded ecological screening
 levels.  However, the Site is almost entirely
 developed for industrial and commercial uses,
 and there is very little undisturbed natural
 habitat.  Also, there are no federal or state
threatened or endangered species  and no
critical environments in the vicinity of the Site.
The presence of structures and pavement
throughout the area, limits potential exposures
of ecological receptors to soil in  this area

 Meade Heights

       From past sampling  events, the organic

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contaminants of concern for the Meade Heights
area include acetone, bis(2-ethylhexyl)phthalate
(DEHP), and methylene chloride.  No
contaminants exceeded the RBCs screening.
Also, known association of these chemicals as
common laboratory contaminants raises doubts
that they are actually present at the Site.

       The inorganics, cadmium and
vanadium, were detected at levels which
exceeded  site-background, but are consistent
with naturally occurring or regional levels in
soils (Dragun, 1988 Soil Chemistry of
Hazardous Materials: ATSDR. 1990
ToxjcoloaicaJ Profile for Vanadium).

       In  one sample, methylene chloride (11
ppb) exceeded its toxicity characteristic
leaching potential screening level (10 ppb).
However, because it has never been
determined to be a contaminant of concern at
the Site in previous studies, only one sample
exceeded  the screening level, and  it  is a  •
common laboratory contaminant (making its
presence suspect), EPA has determined that
there is no discemable risk associated with this
contaminant.

       Reported concentrations of PAHs*'and
inorganics were representative of naturally.
occurring levels and at most present an
insignificant threat to ecological receptors. No
organic contaminants were detected  above the
Biological  Technical Assistance Group's
(STAG) screening levels.

Penn State

       PAHs, similar to the Industrial Area.
and the pesticides; DOT, dieldrin, endosuifan,
endrin, lindane, and chlordane were detected
in the walkway that connects student housing
with the campus.

       Results of the RBC screening indicated
that there  are no unacceptable levels of risk
associated with these soils, nor do the
contaminants appear to be migrating based
upon the soil and ground water data available.

       Barium, cadmium, chromium, dieldrin,
nickel, and PAHs exceeded the leaching
screening levels in isolated occurrences. The
limited occurrence of these elevated levels and
their detection at below health-based
concentrations in ground water indicates that
the soil is not serving as a source of ground
water contamination for these contaminants.

       Reported concentrations of PAHs and
inorganics were representative of naturally
occurring levels and at most present an
insignificant threat to ecological receptors.

Warehouse Area

       Similar to the Industrial Area, soil
samples collected in the Warehouse Area
showed elevated concentrations of PAHs and
some inorganics.  However, evaluation of
potential risks associated with exposure to
these soils indicates that the levels of risk are
acceptable under  current established EPA
guidelines for human exposure as determined
by the risk assessment.

       Reported soil constituents were also
evaluated to assess the potential for soil
constituents to leach into ground  water. The
primary contaminants to exceed leaching
screening levels were barium and PAHs.
However, a review of ground water data
indicates that these constituents are not
present at levels that present concern for the
ground water at the Site based upon the
findings of the risk assessment.

North Base Landfill

       DEHP was detected in 7 of 9 sentinel
wells east of the landfill ranging from 2 ppb to
54 ppb.  The sentinel wells were installed to
provide an early warning should contaminants
from the landfill begin to migrate towards
Middletown's MID-04 public water supply well.
DEHP has not been detected in MID-04, which
draws water from beneath the landfill.

       Carbon tetrachloride (6 ppb to 8 ppb)
was also detected  in one off site, shallow well
slightly above its MCL (5 ppb).  Because it is a
common laboratory contaminant,  the validity of
                                                                               AR300I38

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 its presence, based upon a low concentration
 sample raises doubt that it is actually present
 at the Site.  Also, because it was discovered in
 a shallow well off site, it does not appear to be
 a site related contaminant.

 Susquehanna River

        Quarterly monitoring, as required by
 the 1990 ROD, as modified  by the 1992 ESD,
 has resulted in the detection of several PAHs,
 VOCs, inorganics, and pesticides. Based upon
 the sampling data, these contaminants do not
 appear to be Site related, but are present
 regionally.

        Organic constituents detected in
 surface water appear to be anomalous and do
 not represent a potential threat to ecological
 receptors.  Inorganic constituents are either
 within the range of reported background
 concentrations or they infrequently exceeded
 the Biological Technical Assistance Group
 (STAG) screening levels.

        Organic and inorganic constituents in
 the sediment were generally within the range of
 upstream samples.

 Mead* Heights Stream

        A one time sampling of the stream,
 resulted in the detection of VOCs, PAHs, and
 inorganics in the surface water.  Review of the
 data suggests that upstream and downstream
 concentrations are likely results of natural
variability. Historically,.the area near the
stream has exclusively been used for housing.

 Summary of Site Risks

        During the FFS, an analysis was
conducted to estimate the potential human
 health or environmental problems that could
 result if contaminated media at the site were
 not remediated.  This analysis is commonly
 referred to as the baseline risk assessment
 (RA). Potential human health problems are
 identified by calculating risk levels and hazard
 indices. Potential carcinogenic risks are
 identified by the risk level, and a  1x10* level
indicates one additional case in 1,000,000 that
an individual will develop cancer above the
expected normal rate of approximately 330,000
per 1,000,000.  The hazard index identifies the
potential for the most sensitive individuals to be
adversely affected by noncarcinogenic
chemicals.  If the hazard index exceeds one
(1.0), there may be concern for potential  non-
cancer effects.  As a rule, the greater the value
of the hazard index above 1.0, the greater the
level of concern. Changes in the hazard  index,
however, must be over one or more orders of
magnitude  (e.g., 10 times greater) to be
significant

       In general, throughout all of the studies
conducted  at this Site,  no soil samples were
reported which indicated contamination had
been detected above acceptable health and
environmental based levels.

       A RA was completed on the data
generated by the SSI and  PADOTs
Comprehensive Testing Program.  The results
were integrated with  information regarding Site
use and Site activities in order to derive
appropriate remedial action objectives. The RA
focused on three distinct areas of concern; soil,
ground water, and surface water/sediment
Each of these areas were further divided for
analysis purposes.

       The soils of the Industrial Area, Meade
Heights, the Penn State Area, and the
Warehouse Area were evaluated individually
and were determined to contain levels below
health-based.and environmental concern.
Cumulative  risks for workers and residential
exposures were estimated using RBCs. In
addition, the RA also evaluated the potential for
soils to pose a threat to ecological receptors.
Based on the results  of the RA and current and
anticipated  future Site use scenarios, more fully
described in the FFS, no further actions are
necessary to address soils at the Site since the
acceptable  range for health-based levels of 10"*
to 10*, as defined in  the NCP, are not
exceeded and EPA's STAG group has
confirmed that no unacceptable threat exists to
the ecology in the area. The noncarcinogenic
hazard indices were determined to be less than

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one (1).

       tt should be noted that in the Terminal
Area of the Industrial Area, the potential
noncarcinogenic hazard index exceeded one
(1), based almost entirely on the presence of
manganese, which has not been identified as a
Site related contaminant  However, when
using the recent Integrated Risk Information
System (IRIS) reference dose for manganese,
the hazard index drops below one (1).

       Elevated levels of several VOCs, PCBs,
and inorganic constituents were detected in
Vault J-5 of the storm sewer system
(approximately  100 feet west of the
southwestern corner of Building 208) during  the
SSI. A review of the soil and ground water
data for this area suggests that no source is
present in these media.  The USAGE has
removed the storm sewer sediment, which
contained the hazardous constituents, and the
vault was resampled and verified that the
presence of the hazardous substances was not
due to an on site source. Therefore this
segment of the storm sewer system presents
no identified threat to human health and the
environment The remainder of the storm
sewer system will be addressed during an on-
going storm sewer discharge permitting
process, which  is not a part of this Superfund
action.

       Ground water in the Industrial Area, the
North Base Landfill Area, and residential wells
was evaluated in the RA.  The primary
constituent of concern in ground water in the
Industrial Area is TCE.  However, as previously
discussed, remedial efforts are currently in
place at the Site to manage TCE contamination
in ground water in the Industrial and  Runway
Areas. Thus, under current and future realistic
use scenarios, there are no unacceptable risks
associated with the use of untreated  ground
water In these areas. Ground water in other
areas was found to contain low levels of a few
contaminants; however, none were determined
to be a concern or a potential future public
health threat because of the lack of exposure
potential and the presence of institutional
controls already in-place.
       DEHP was detected in 7 of 9 sentinel
wells east of the North Base Landfill ranging
from 2 ppb to 54 ppb.  The sentinel wells were
installed to provide an early warning should
contaminants from the landfill begin to migrate
towards Middletown's MID-04 public water
supply well.  DEHP has not been detected  in
MID-04, which draws water from beneath the
landfill. At those concentrations, even
uncontrolled use of the ground water by the
public would only represent a carcinogenic
risk of 10*.

       Surface water and sediment samples
were collectad from the Susquehanna River
and from the Meade Heights stream. Human
exposure to the contaminants detected in the
surface water and sediments in the
Susquehanna River was shown to be limited
because of the restricted access to the
shoreline.  In the Meade Heights Area, the only
contaminants of concern detected were
inorganics. A comparison of upgradient and
downgradient samples indicated that the
concentrations detected were likely naturally
occurring. The sample results, coupled with
the fact that the most likely exposure to the
constituents would be from children playing in
the stream, and that the inorganics are poorly
absorbed  across the skin  indicates that no
unacceptable risk is expected to be associated
with these constituents. EPA has determined
that ecological receptors are not adversely
impacted above acceptable levels based upon
the constituents found in the surface water  and
sediments.

       No contaminants of concern were
identified in the surface water or sediment
above BTAG screening levels.

       Based on the RA, a summary of the
Site's risk management conclusions are
presented below.

•  No additional action is necessary to address
soils at the Site.

'•  Institutional restrictions on ground water use
will be continued at the Site.
                                              8
                                                                               flR300H*0

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•  It is expected that pumping and treating
ground water in the Industrial Area will continue
to control most of the discharge of ground
water by containment to the Susquehanna
River.

•  On-going monitoring of surface water and
sediment in the Susquehanna River is required
as part of the 1990 ROD.  In addition, two
locations downgradient from the J-5 storm
drain, situated next to building 208, are also to
be sampled quarterly and  evaluated in five
years.  The sampling frequency may be
modified by PADEP after one year. These
locations are the J-5 storm drain and the outfall
of the J-5 storm line at Post Run.  No other
actions are deemed necessary at this time.

•  On-going monitoring of the sentinel wells at
the North Base Landfill Area is required as part
of the 1990 ROD as protection for well MID-04.
No other actions for this area are deemed
necessary at this time.

•  No  action is required for  surface water or
sediment in Meade Heights.

•  In the event that the HIA  should cease or
reduce the pumping of the production wells,
PADEP will assess the potential  for currently
contained hazardous substances to migrate
and may impose a sampling and review period
(not to initially exceed 5 years),  to assess
whether any impact is occurring regarding the
Susquehanna River.  After the initial review,
PADEP will again review the Site's status and
determine if additional action is  warranted.

• As required by the 1990  ROD, ground water
use will be restricted in the event any new wells
or modification of usage to existing wells are to
be implemented at the Site.  The extracted
ground water must be tested and the results
reported to PADEP.  Ground water use at the
Site will require a permit or approval by PADEP
prior to use:

       Based on the results of  the SSI and
RA, no additional action than that already
required by the 1987 ROD and the 1990 ROD,
as modified by the 1992 ESD, is required at the
Site.  It should also be noted that based upon
this same study, the objectives of the
Harrisburg Airport Master Plan can be realized
within the requirements of the "No Further
Action" alternative by utilizing engineering and
institutional controls.

Description of °No Further Action' Alternative

       Based  on the results of the RA
conducted as part of this SSI, EPA has
determined that the conditions at the Site, as
controlled by the previous two RODs and ESD,
pose no unacceptable current or potential
threat to human health or the environment and
no additional remedial actions need to be
implemented.  Although potentially hazardous
constituents are present in Site ground water,
measures that are compliant with ARARs and
are more fully described in the 1987 ROD, the
1990 ROD and the 1992 ESD, are already
being taken to  remedy that condition. All of
the requirements outlined in the 1987 ROD and
the 1990  ROD, as modified by the 1992 ESD;
will remain in effect  Consequently, the Site
satisfies the requirements for a "No Action*
determination for operable unit #3.

       The ongoing nature of the previous
remedial actions and the additional monitoring
of the J-5 storm drain have been taken into
account prior to proposing the selection of the
"No Further Action" alternative for this operable
unit

Evaluation of Previous Remedial Actions

       Based upon the results of the RA, the
"No Further Action" alternative is being
proposed for this Site's final operable unit  It
should be noted, however, that several interim
remedial actions addressing ground water were
required by both the 1987 ROD and the 1990
ROD, as modified by the 1992 ESD.  These
actions are more fully described in the RODs,
which are a part of the Administrative Record.
Based upon an evaluation of the RODs
remedial actions at the time of the issuance,
EPA has determined that these actions provide
overall protection of human health and the
environment. Furthermore, EPA has identified

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all ARARs for this Site in the previous two
RODs and ESD.  Implementation of those
remedies resulted in achievement of all ARARs.

       All of the requirements outlined in the
1987 ROD and 1990 ROD, as modified by the
1992 ESD, will remain in effect and are
necessary in order to provide for the
protectiveness of human health and the
environment and to comply with ARARs.

Glossary

Administrative Record: An official compilation
of documents, data, reports, and other
information that is available to the public and
considered important to the status of and
decisions made relative to a Superfund site..

Applicable or Relevant and Appropriate
Requirements (ARARs): The federal and state
requirements that a selected remedy must
attain.  These requirements may vary among
sites and alternatives.

Comprehensive Environmental Response,
Compensation and Liability Act (CERCLA), or
Superfund: A federal law passed in 1980 and
modified in 1986 by the Superfund
Amendments and Reauthorization Act  The Act
created a trust fund, known as Superfund, to
investigate and clean up abandoned  or
uncontrolled hazardous waste sites.

Ground water: Water found beneath the
earth's surface in geologic formations that are
fully saturated. When present in quantity,
ground water can be used as a water supply.

Hazard Index: A value used to evaluate the
potential for noncarcinogenic effects  that occur
m humans.

National Priorities List (NPL): EPA's list of the
nation's top priority hazardous waste sites that
are eligible to receive federal money for
response under Superfund.

Operable Unit (OU): A portion  of a Superfund
site that has been conceptually separated from
the rest of the site to allow for easier
management.
Record of Decision (ROD);  A legal document
that describes the final remedial actions
selected for a Superfund site, why the remedial
actions were chosen and others not how. much
they cost, and how the public responded.

Remedial Action:  Action to protect human
health and the environment by restoring all
media to their beneficial uses within a
reasonable time frame.

Remedial Investigation/Feasibility Study (RI/FS):
A two-part study of a hazardous waste site that
supports the selection at a remedial action for
a site. The first part, the Rl, identifies the
nature and extent of contamination at the site.
The second part, the FS, identifies  and
evaluates alternatives for addressing the
contamination.

Volatile Organic Compounds (VOCs):  Organic
liquids that readily evaporate under
atmospheric conditions.  Example VOCs
include vinyl chloride and trichloroethene
(TCE).
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                                                                             AR30GU2

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Responsiveness Summary
No comments were received during the 30-day public comment period beginning August 1, 1996 and
ending August 30,1996. In addition as offered in the press release printed in the July 31, 1996 edition
of the Press and Journal of Middletown and a newspaper article appearing in the Patriot News about
the same time, no verbal or written request was received by EPA requesting that a public meeting be
held.
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