United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R03-91/112
June 1991
&EPA Superfund
Record of Decision:
AVCO Lycoming-Williamsport
Division, PA
-------
50272-101
REPORT DOCUMENTATION i. REPORT NO. 2,
PAGE EPA/ROD/R03-91/112
4. Tin* and Subtitle
SUPERFUND RECORD OF DECISION
VCO Lycoming-Williamsport Division, PA
.rst Remedial Action
i. Author)*)
9. Performing Organization Name ind Address
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, S.w.
Washington, D.C. 20460
3. Recipient" • Accession No.
5. Report Date
06/28/91
6.
8. Performing Organization RepL No.
10. ProjecVTask/Worli Unit No.
11. Contnct(C) or Grsnt(G) No.
(C)
(G)
13. Type of Report & Period Covered
800/000
14.
15. Supplementary Note*
18. Abstract (Limit: 200 word!)
The 28-acre AVCO Lycoming-Williamsport Division site is an active manufacturing
facility in Williamsport, Pennsylvania. Surrounding land use is primarily
residential. The site overlies a surficial glacial aquifer and a deeper bedrock
aquifer that are used as seasonal sources of drinking water. Ground water is pumped
from the Williamsport Municipal Water Authority (WMWA) well field located 3,000 feet
outh of the site. Wetlands are located near the site in the 100-year floodplain of
ycoming Creek and the Susquehanna River. From 1929 until present, various
manufacturing companies including a bicycle and sewing machine manufacturing plant, a
sandpaper plant, a tool and die shop, a silk plant, and aircraft engine manufacturing
plant have been located onsite. Possible sources of onsite contamination include
improper-waste disposal in a "dry well", laboratory chemical disposal in a coolant
well, spillage and dumping in metal plating areas, a sludge holding lagoon, cutting
oils from a metal chipster sump, degreasing areas, and chemical storage areas. The
site also contains approximately 40 underground storage tanks that are presently
being abandoned or upgraded. In 1984, the State identified VOC contamination in the
WMWA well field. In 1985, monitoring and recovery wells were installed onsite and
(See Attached Page)
17. Document An*ly»ii a. Descriptors
Record of Decision - AVCO Lycoming-Williamsport Division, PA
First Remedial Action
Contaminated Medium: gw
Key Contaminants: VOCs (TCE), metals (chromium)
b. ktentiflers/Open-Ended Terms
c. COSAT1 Reid/Group
18. Availability Statement
19. Security Class (This Report)
None
20. Security Class (This Page)
None
21. No. of Pages
152
22. Price
(See ANSI-Z39.18)
See Instruction* on Reverse
OPTIONAL FORM 272 (4-77)
(Formerly NT1S-35)
Department of Commerce
-------
SPA/RCD/R02-91/112
AVCO Lycoming-Wiiliamsport Division, ?A
First Remedial Action
Absr-act (Cor.tir.ued)
of. te to identify t.-.e source of contamination, which was determined to be the AVCO
plant. In 1386, the State approved the AVCO remedial action plan, which included
installation of an air stripping system to treat water from three onsite and two
ijffsite recovery wells, and discharge to Lycoming Creek. This remedial action remains
in effect. Between 1989 and 1991, a RI/FS study was conducted to further characterize
the contamination and source areas. This Record of Decision (ROD) addresses management
jf migration of contaminated ground water from the onsite area. Remediation of offsite
ground water will be addressed in a subsequent ROD. The primary contaminants of
concern affecting the ground water are VGCs including TCE and metals including
chromium.
The selected remedial action fcr this site includes pumping and treatment of
contaminated ground water using an onsite treatment facility that utilizes
precipitation, coagulation, flocculation, and air stripping; treating air stripper
off-gases using Best Available Technology (BAT), possibly granular activated carbon or
fume incineration; dewatering and offsite disposal of residual precipitation sludge and
spent carbon filters; discharging treated water onsite to surface water; monitoring
ground water; and implementing institutional controls including land use restrictions.
The estimated present worth cost for this remedial action is 39,300,000, which includes
an annual CsM cost of :-;-;Z,300 for 30 years.
?£PFCP.MA::C£ STA::2A?i; :=. ""A12: jrcund water cleanup standards are based on the more
stringent of Federal xCLs or non-zero XCLGs, or background levels. Chemical-specific
gr - were net provided.
-------
RECORD 07 DECISION
AVCO LYCOMING SITE
DECLARATION
SITE NAME AND LOCATION
AVCO Lycoming Site
williamsport, Lycoming County, Pennsylvania
STATEMENT O? BASIS AND PURPOSE
This decision document presents the selected remedial action plan
for Operable Unit One at the AVCO Lycoming Site (the site) in
Williamsport, Lycoming County, Pennsylvania which was chosen in
accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980, as amended by the
Superfund Amendments and Reauthorization act of 1986, U.S.C.
Section 9601 (CERCLA), and, to the ext'ent practicable, the
National Oil and Hazardous Substances Pollution Contingency Plan.
This decision is based upon and documented in the contents of the
Administrative Record. The attached index identifies the items
which comprise the Administrative Record.
The Commonwealth of Pennsylvania has reviewed, commented upon,
and concurred in this decision.
ASSESSMENT OF THE SITE
Pursuant to duly delegated authority, I hereby determine,
pursuant to Section 106 of CERCLA, that actual or threatened
releases of hazardous substances from this Site, as discussed
under Summary of Site Risks in this document, if not addressed
by implementing the response action selected in this Record of
Decision (ROD), may present an imminent and substantial
endangerment to public health, welfare, or the environment.
DESCRIPTZOM OF TEX REMEDY
The remedial action plan in this document for Operable Unit One
is presented as the permanent remedy for containing, recovering
and treating the onsite ground water contamination at the Site.
Under this remedy, ground water recovery veils would be installed
on the downgradient side of the facility to contain contaminated
ground water and thus control further offsite migration. The
contaminated ground water will be recovered through a series of
existing and newly installed recovery wells, with the long-term
goal of returning the ground water to its most beneficial use.
This remedy also provides for additional protection by
-------
implementing institutional centrals in the form of limiting
future property use to these activities compatible with site
This remedy is for Operable Unit One and only addresses the
onsite contaminated ground water. The offsite contaminated
ground water plume will continue to be remediated through the
existing offsite reccvery-ar.d-treatment systems, as required by
the Consent Order and Agreement between AVCO and the Common-
wealth of Pennsylvania. This offsite plume will be discussed in
a separate operable unit. Additional studies will be performed
for this offsite operable unit to determine the most appropriate
action to be taken by EPA in a future Record of Decision.
STATUTORY DETERMINATIONS
Pursuant to duly delegated authority, I hereby determine
that the selected remedy is protective of human health and the
environment, complies with Federal and State retirements that
legally are applicable or relevant and appropriate to the
remedial action, and is cost-effective as required under Section
121(d) of CERCLA, 42 U.S.C. Section 9621(d). With respect to a
principal threat at the site, the contaminated ground water, the
remedy satisfies the statutory preference, as set forth in
Section 121(b) of CERCLA, 42 U.S.C. Section 9621(b), for remedia
actions in which treatment that reduces toxicity, mobility, or
volume is a principal element. Finally, it is determined that
this remedy utilizes permanent solutions and alternative
technologies to the maximum extent practicable.
Because this remedy will result in hazardous substances
remaining onsite above health-based levels, a review will be
conducted within five years after the commencement of the
remedial action to ensure that human health and the environment
continue to be adequately protected by the remedy.
Edwin B. EricJcson Date
Regional Administrator
Region III
-------
RECORD OF DECISION
TABLE OF CONTENTS
Page
I SITE NAME, DESCRIPTION, AND LOCATION 1
A. Site Name and Location 1
B. Site History and Enforcement Activities l
C. Highlights of Community Participation 3
D. Scope and Role of Operable Units 9
E. Site Characteristics 9
F. Nature and Extent of Contamination 23
II. SUMMARY OF SITE RISKS 45
III. DESCRIPTION OF ALTERNATIVES 68
IV. COMPARATIVE ANALYSIS OF ALTERNATIVES 73
V. DESCRIPTION OF THE SELECTION REMEDY 78
VI. STATUTORY DETERMINATIONS 80
ATTACHMENTS
A. Responsiveness Summary
B. Administrative Record Index
-------
Sire Description ar.ci Sur-T.ary of Remedial Alternative Selection
for the AVCO Ly com ing Superfur.d Site
Wi Ilia-sport , lyccr.ir.g County, Pennsylvania
The AVCC Lyooning Site is an active manufacturing facility
located at 552 Oliver Street in Williamsport, Lyconing County,
Pennsylvania (Figure 1) . Williamsport is situated in a valley that
is located in the Valley and Ridge Physiographic Province. The
site is approximately 23 acres in size with about 35 percent of the
property covered by buildings or pavement. The ziajor topographic
feature in the vicinity of the site is a steep ridge to the north
that rises to a height of approximately 210 feet above the site.
The elevation of the site is approximately 545 feet above mean sea
level (MSL) . The elevation of the Susquehanna River, which is
about 5,000 feet south of the site, is approximately 510 feet MSL.
The 35-foot change in elevation between the site and the river is
gradual, with a grade of approximately 0.7 percent.
The area surrounding the site is primarily residential. Two
public parks, Memorial Park and Elm Park, are located south and
southwest of the site, within the residential area. These parks
contain baseball fields, a public swimming pool, skateboard park
and playground. Along the southern boundary of the park area is
the Conrail Railroad track which runs east-west across Lyconing
Creek. Lycoming Creek flows south and is located approximately
2,000 feet southwest of the site. The creek drains into the
Susquehanna River. The Williamsport Municipal Water Authority
(WMWA) well field is approximately 3,000 feet south of the site.
Surface water in the vicinity of the site, including Lycoming
Creek and the Susquehanna River, is used for recreation and water
supply. In the Williamsport area, the primary supplier of water
is the WMWA which obtains most of its water from surface water
reservoirs located on the opposite side of the Susquehanna River
south of Williamsport. The WMWA also uses a well field, located
east and vest of Lycoming Creek, as a water supply. The veil field
consists of nine veils dug into the glacial and alluvial deposits
in the Lycooing Creek Valley. The veil field is used primarily in
the summer months as a backup supply vhen the reservoir yield is
low.
Site History and Enforcement Activities
t
The Aviation Corporation vas incorporated in 1929. In
1935, the Aviation Manufacturing Corporation, a subsidiary company,
was established under which the Williamsport Lycoming Division was
formed. By 1939, the Aviation Corporation had purchased the
majority of the present site property.
-------
Figure 1
Site Location Map
Textron Lycoming, Williamsport, Pennsylvania
TEXTRON
PLANT
SOUICB: U3QS TooogripMe Quadringto. 7.5 Mktut* S«i«s;
SUM. VWI W M-Md -9«
ORIGINAL
-------
In July 1344, during Wcrld War II, part of the facility was
constructed conjunctively by the Cefer.se Plant Corporation and the
Aviation Corporation for use as an experimental "laboratory. On •
January 22, 1947, the Aviation Corporation granted part of the
property to Reconstruction Finance Corporation, the parent
Corporation of Defense Plant Corporation, in exchange for financial
aid for further facility expansion. This property was subsequently
acquired by the United States of America by quitclaim deed from
Reconstruction Finance Corporation on May 25, 1943. In November,
1950, an Air Force contract was negotiated between AVCO and the
U.S. Government to consolidate the use of various machine tools and
the laboratory test building. At this time, part of the facility
was owned by the U.S. Government who leased it to AVCO.
On April 23, 1947, the Aviation Corporation changed its name
to AVCO Manufacturing Corporation, which subsequently changed its
name to AVCO Corporation on April 20, 1954.. On December 15, 1961,
the property and plant were determined to be surplus property by
the General Services Administration and were granted back to AVCO
Corporation.
In February 1935, AVCO Corporation, which included AVCO
Lycoming, Williamsport Division, was acquired by Textron, Inc., a
Delaware corporation based in Rhode Island. AVCO Corporation
maintains the status of a wholly-owned subsidiary of Textron.
Portions of the AVCO Lycoming Site were first used for
manufacturing purposes around the turn of the century.
Manufacturing operations consisted of a bicycle and sewing machine
manufacturing facility, a sandpaper plant, a tool and die shop and
a silk plant. During the 1920s, the property was purchased by AVCO
Corporation and operations focused primarily on the manufacture and
repair of aircraft engines. Prior to 1940, automobile and boat
engines were also produced at the facility.
Past waste disposal practices at the site are not well
documented. Several potential areas of concern or source areas
were identified through employee interviews, employees' general
knowledge of plant history and aerial photographs. These areas of
concern include a "dry wall", coolant water wall, past plating
areas, a temporary sludge holding lagoon, chipster (metal chips)
sump, degraaaing areas and chemical storage areas and underground
storage tanJca (Figure 2, Tabla 1). These areas are described
briefly in tha following paragraphs.
The dry wall, it is believed, consisted of an old septic basin
from a house that may have existed on tha property at the turn of
the century. The dry wall was located in the center of the plant
property and its depth is unknown. It has been reported that waste
disposal in this well was a common practice until it was sealed in
the 1950s. The well has sinca been covered over with a roadway.
-------
Figure 2
Potential Areas of Concern
Textron Lycomlng, Wllilamaport, Pennsylvania
14
I
,n*f
-------
index
PotsntUI Artas of Concam, T«xtron Lycommg,
Wllllimtoort. Pennsylvania
723-01-01-01
Location of past or present iegreaser unit.
2. Waste-water treatment area and location of former lagoon
;since closed).
3. Former plating and heat treatment area, dirt Qoor in past.
Nltrtter and cyanide furnaces located here in tie past.
Chrome, cadmium, nitrnter furnaces, cyanide base
solutions.
4. Former drum and chemical storage areas for oil and
chemicals.
5. Location of 1.000-galion ammonia tank, -ince removed.
6. TCE distilling area, possible spillage in past plating area.
7. Paint spraying booth.
8. Area of engine and engine part washing and steam
cleaning.
9. Drums of carbon tetrachionde stored here in past.
10. Former heat-treating and plating area.
11. Past impregnating room • 1940s.
12. Former area of transformer, oil drained once in 1950s.
13. Plant deep well, drilled in 1929 (approximately ) and used
for cooling water, and presently as Recovery Well RW-2.
14. Former gunk room, earty 1950s.
15. Put porous chrome plating area.
16. Former coolant wen location, where waste residuals from
the lab an reportad to haw been washed down. Drilled in
1930s and sealed tn the 1950s.
17. Former "dry wtfl": sump of unknown depth into which
wasts materials were reportedly disposed.
18. Past area of perforated concrete floor for drainage •
possdbijr drained, onto dirt.
*9* s^BflC 4%
-------
During the 1930s, a coolant water well was drilled
approximately 200 feet north of the dry well. Although no well
leg exists to verify its depth, this well is suspected to have been
about 100 to 150 feet deep. Due to its proximity to the chemical
laboratory, it has been reported that waste residuals from the lab
may have been washed down the well. This coolant well was
abandoned and sealed in the 1950s.
The past plating areas are of concern as a result of cadmium,
chromium, copper, tin, lead, nickel and black oxide plating that
took place over the years. The plating process at the plant
involves three steps. First the engine parts are degreased with
a solvent [usually trichloroethylene (TCE)], then the parts undergo
an acid rinse, and finally each part undergoes a specific plating
process. The acid rinse waters and plating wastes are then treated
in the on-site Waste Water Treatment Plant (WWTP). In the past,
plating operations took place mainly in the northwest portion of
the plant. In one plating area there was a dirt floor for many
years. This floor was paved in the early 1950s. The plating
operations in this area ended in the late 1960s.
The temporary sludge holding lagoon was located in the
northwest section of the property. For approximately 3 or 4 years
during the 1950s, this lagoon was used to hold sludge from the WWTP
located in the same area. The lagoon was lined with plastic and
was approximately 25 feet wide and 10 feet deep. Sludge from this
lagoon was eventually shipped off-site for disposal and the lagoon
was filled with native materials. Present plant operations, which
involve plating, waste water treatment and sludge handling, are in
accordance with state and federal regulations. Plating operations
have since moved to a new area of the plant and the old WWTP is
being phased out while a new WWTP is being phased into operation.
Sludges from the WWTP, used solvents and other wastes are
transported off-site for disposal or reclamation.
The concrete chipster sump is being used for collecting
cutting oils from metal scraps stored for recycling. It is
approximately 200 feet vest of Monitoring Well 5 (MW-5), and may
be a past source area for organics as at one time it was also used
to evaporate solvents.
Other potential source areas are locations where degreasing
took place and areas of chemical storage. Solvents used in
previous degreasing locations are known to have leaked or spilled
on the plant floor possibly entering the plant sever system or
other areas of the plant. Chemical storage existed primarily in
areas vhere they vere used for manufacturing processes. Temporary
chemical storage areas vere also located in the east end of the
plant, and near the experimental laboratory in the north end of the
plant.
-------
Many of these*
tanks have been taken cut of service and are being abandoned or
upgraded in accordance with underground Storage Tank (UST)
regulations. The AVCO Lvcoaing Site is a generator of hazardous
waste in accordance with the Resource Conservation and Recovery
Act (RCRA). However, because the waste generated is stored on site
for less than 90 days a RCRA Part 3 permit is not required.
In 1934, volatile organic compounds (VOCs), specifically TCE
and 1,2-trans-dichloroethylene (CCE), were discovered in the'wMWA
water supply well field located south of Third Street. After a
sore comprehensive analysis of the ground water by the WMWA for an
expanded list of VCCs, it was confirmed that TCE and DCE were the
primary compounds of concern in the well field. The WMWA notified
the Pennsylvania Department of Environmental Resources (PADER) of
the situation and' in November 1984, PADER informed site
representatives of the problem. In December 1984, and January
1985, an investigation was conducted by PADER and included ground-
water sampling from wells in the WMWA well field, other accessible
wells in the area and a well on the site property. The results of
this investigation led PADER to suspect that the source of VOC
contamination was the AVCO Lycoming Site property.
During 1935, Chester Engineers conducted a remedial
investigation at the request of AVCO Lycoming representatives.
This investigation included the installation of on-site and off-
site monitoring wells and on-site ground-water recovery wells.
During the investigation, reports were submitted to PADER. The
results of this investigation revealed that contaminants in the
overburden aquifer beneath the site were migrating from the site
in a southerly direction.
In November 1985, a Consent Order and Agreement (COA) was
entered between PADER and the AVCO Corporation through its AVCO
Lycoming Division. The COA required that a Remedial Action Plan
be developed to continue the remedial investigation to determine
the extent of contamination, identify and implement the appropriate
remedial action in contaminated areas and to continue ground-water
monitoring to define the progress of the remedial activities. In
May 1986, PADER approved the Remedial Action Plan which included
ground-water recovery from 3 on-site recovery wells and 2 off-site
recovery wells. Treatment of this recovered ground water is being
performed through air stripping. The treated ground water is
discharged to Lycoming Creek under a National Pollution Discharge
Elimination' System Permit. The emissions from the air stripping
towers are In compliance with the criteria deemed acceptable at the
time they were reviewed. The approval of the Remedial Action Plan
also includes quarterly ground-water monitoring. The remedial
action as required by the COA remains in effect.
-------
On January 22, 1987, EPA proposed the AVCO Lycoming site en
the sixth update of the National Priorities List. Textron Inc.,
the parent corporation of AVCO Lycoming, was notified by letter
from EPA on July is, 1987, that the Agency intended to conduct or
oversee a Remedial Investigation and Feasibility Study (RI/FS) at
the AVCO Lycoming Site. Through this general notification letter,
EPA also requested information pursuant to provisions of Section
104(e) of CERCLA, 42 U.S.C.9604(e), and/or Section 3007 of RCRA,
42 U.S.C. 6927. On October 2, 1987, a response to the
notification/104(e) information request letter was sent by the
Textron Lycoming Division (formerly AVCO Lycoming) of AVCO
Corporation to EPA expressing a willingness to participate in the
RI/FS. A second response was submitted on October 5, 1987, that
included referenced documents in response to EPA's questions in
the letter.
The AVCO Lycoming Site was placed on the National Priorities
List (NPL) on February 12, 1990, having a score of 42.24. Between
1989 and 1991, an RI/FS was conducted by AVCO Corporation through
its Textron Lycoming Division, under the guidance of EPA and PADER.
The RI/FS was performed in accordance with a COA signed in June
1988, between AVCO and EPA. The RI/FS was conducted to identify
the types, quantities and locations of contaminants and to develop
ways of addressing the contamination problems. The RI included a
risk assessment that determined which of the contaminants detected
posed a risk to human health or the environment. A Summary
Chronology of activities and enforcement history at the site is
presented in the RI.
Highlights of Community Participation
The RI/FS, Proposed Plan and background documentation for the
AVCO Lycoming Site were made available to the public on April 17,
1991, in the local information and administrative record repository
at the James V. Brown Library of williamsport and Lycoming County
located in williamsport, Pennsylvania. Notice of the availability
of these documents, of a public comment period, and a public
meeting was published in The williamsport Sun-Gazette on April 17,
1991. The public comment period was held from April 17, 1991
through May 16, 1991. Additionally, a public meeting was held at
7:00 P.M. on May 2, 1991, at the Sheraton Hotel in Williamsport.
At this meeting representatives from EPA and PADER answered
questions about the AVCO Lycoming Site and the remedial
alternatives under consideration and accepted comments from the
attendees.' A transcript of the public meeting was maintained in
accordance' with §117(a)(2) of CERCLA, 42 U.S.C. §9617(a)(2).
Written comments received during the public comment period are
addressed in the Responsiveness Summary which is an attachment to
this Record of Decision (ROD). The above actions satisfy the
requirements of Sections 113(k)(2)(B)(i-v) and 117 of CERCLA, 42
U.S.C. §§9613(k)(2)(i-v) and §9617. All documents that form the
8
-------
basis for the selection cf the remedial decisions contained in this
ROD are included in the Administrative Record for this site and car
be reviewed cr referred to for additional information.
Sccce
This is the first remedy proposed by EPA for the AVCO Lycoming
Site. However, contaminated ground water on-site and off-site is
currently being recovered, treated and monitored in accordance with
a November 1935, CCA between PADER and AVCO Lyconing. The scope
cf the remedy in this RCD for Operable Unit 1 (OU-l) will be to
address the en-site contaminated ground water. There was no
principal threat identified at the AVCO Lycoming Site.
Ground-water contamination is the media of concern at the AVCO
Lyccning Site. Contaminated ground water exists on-site and has
migrated off-site as far south as the WMWA well field. The goal
of the remedial action described in this ROD will be to recover on-
site contaminated ground water and restore the ground water to its
beneficial use, which is a potential drinJcing-water source. The
off-site contaminated ground water will continue to be recovered
and treated through the existing system installed in accordance
with the COA between PADER and AVCO Lycoming. However, the
existing off-site ground-water recovery and treatment system needs
rr.cdif ications to recover a greater portion of the contamination and
reduce the remediation time frame, as well as to provide a greater
level of protection to the WMWA well field. Therefore, the off-
site ground-water contamination will be a separate operable unit
(OC-2) to be addressed by EPA in a future ROD. This future ROD
will be based on additional studies.
Summary of Site Characteristics
Geology
The geology in the area of the AVCO Lycoming Site consists of
unconsolidated valley fill deposits of Quaternary Age and
consolidated bedrock of Devonian Age. A description of these units
is provided below.
Unconsolidated Valley Fill Deposits
The AVCO Lycoming Site is located at the northeastern edge of
the glacial floodplain formed along Lycoming Creek and the west
branch of the Susquehanna River. Unconsolidated alluvial and
glacial deposits (consisting of sand, gravel, cobbles, and small
boulders with relatively minor amounts of silt and clay,
collectively termed "overburden") underlie the floodplain and lie
-------
on bedrock. Some clayey sands and silts were noted in isolated
areas of the site at the time the drilling was performed during
the RI. The thickness of the overburden ranges from 16.5 to 30
feet beneath the AVCO Lycoming Site and thickens as the topography
slopes toward Lycoming Creek and the Susquehanna River. The
overburden thickness is related to the elevation of the underlying
bedrock. In general, the plant is situated at the base of steeply
sloped terrain to the north and is located on top of a "bedrock
high," that "drops-off" to the southwest, south, and southeast.
This bedrock high extends from the southwestern section of the Site
to the Elm Park Area. The southwestward extension of the bedrock
high forms a "ridge" oriented northeast/southwest.
Because of the configuration of the bedrock surface, the
thinnest overburden is found at the north end of the plant
(approximately 16 to 20 feet thick), and in Elm Park along the top
of the northeast, southwest-trending ridge (approximately 14 to 18
feet thick). The presence of the bedrock high results in
overburden thicknesses that are somewhat uniform beneath the Site
ranging from 25 to 35 feet beneath most of the property. The
overburden thickens considerably along the eastern and western
edges of the study area, and towards the Susquehanna River to the
south. The thickness of the overburden varies somewhat across the
site property. The thinnest section of the overburden beneath the
plant was 16.5 feet in soil boring SB-1 at the far west end of the
site. The thickest section is 37.5 feet observed in MW-9 in the
eastern end of the Site.
In the western portion of the site, overburden was found to
increase in thickness in a southwesterly direction towards Lycoming
Creek, from a minimum of 16.5 feet near SB-1 on the far west
portion of the site property to a maximum of 48 feet in MW-71 in
Memorial Park. In the eastern section of the site, the overburden
is thickest towards the southeast from the plant facility ranging
from approximately 30 feet (near MW-8, MW-7 and MW-6) along the
site's south and southeastern boundaries to 60 feet in the vicinity
of MW-66 and MW-67. This thickening is a result of a rather abrupt
drop in bedrock elevation in this area. Continuing in the
southeasterly direction, the overburden thins to 40 feet in the
vicinity of KW-73. This area southeast of the site, between MW-
66 and MW-73, is apparently a trough-like elongated (low) area in
the bedrock with the result that overburden thicknesses are greater
in this area.
The overburden beneath the site consists of unsorted (well-
graded) alluvial and glacial deposits. The material ranges from
silty fine1 sand to large, rounded to sub-rounded boulders and
displays a'high variability in grain size of the matrix material.
The overburden appears to become more uniform in the south end of
the site, but the distribution and frequency of pebbles and large
boulders increases. In the vicinity of the old Human Resources
building, borings indicated well-sorted (poorly graded), uniform
10
-------
aediua grained sand and silt, to a depth of up to 7 feet indicating
that fill aaterial was probably used during the construction of
this building. in addition, fill aaterial was evident in aany ct
the upper portions (less than 3 feet) of the soil borings,
consisting of brick, concrete, asphalt and "factory fill aaterial."
The overburden deposits south of the site become more unifora
and less variable in coapcsition. The deposits consist of
unconsolidated fine to coarse sands and gravels with some sandstone
and shale pebbles. Closer to the Susquehanna River, acre clays and
silts are evident in boring logs obtained from U.S. Aray Corp of
Engineers. In some cases, the clays were reported to have the
appearance of glacial tills, but did not appear to be continuous.
Bedrock
Bedrock strata in the study area are units of the Upper
Devonian Period. From oldest to youngest, they are the Marcellus
Formation, the Mahantango Formation, the Harrell Formation, and
the Brallier Formation. The Marcellus Formation underlies the
lower portion of the WMWA well field, near the northern boundary
of the Susquehanna River. The formation consists of carbonaceous
shales with thin beds of soft clay. The Mahantango Formation
underlies the area east and south of the site. With the exception
of the Tully Member of this formation, the Mahantango Formation is
comprised primarily of interbedded silty shales and shaley
siltstones. The lime-rich units of the Tully member mark the upper
200 feet of the Mahantango Formation and are the units of principal
concern in terms of ground-water conditions in the study area.
This unit underlies approximately 60 percent of the plant property.
The Tully Member consists of variable thicknesses of interbedded
limestone and shale. The Harrell Formation underlies the western
most portion of the site area and is a homogeneous shale with
scattered thin beds of laminated silty shale. The Brallier
Formation underlies the area northwest of the site. This
formation consists of interbedded siltstones and silty shales. A
generalized geologic section for the site is presented in Table 2.
The configuration of the buried bedrock surface based upon the RI
and previous investigations is presented in Figure 3.
The most distinct features are the presence of a buried
bedrock ridge, generally oriented parallel to the strike of the
limestone in the Tully Member and an adjacent bedrock low toward
the south also paralleling strike. Soft, black clayey shale of
the Harre^l Formation overlies (stratigraphically) the Tully
Limestone to the northwest, and Mahantango gray shale is the
underlying' lithology which occurs in the subsurface toward the
southeast. The bedrock, high beneath the site and the bedrock ridge
extending southwest from the plant is the result of the greater
resistance to weathering and erosion exhibited by the limestone in
11
-------
Tahle 2
Oanarataad Q»a<»ali
laf Study Ar*a f
72» •!-•*•)
08
OD
and
Silunan
lawai Devonian
and UfeiM Sdunan
DaaatM
UcAHavaN
FM
FM
Foimalion
0 U«
1*0
I. ••• I.7M
32k
100
by f\mntn( xatoi. tea. i
Mghl abva-pay. wary In*
^ MM »-r
b«M pay. »•>- *
and kgM •*•• aiay.
t4 ahato
!•*
to
200 to 2»0 toat to
(iay feMatoMa
i toviai part n*
(lay. M» to aiadk*»-
I aMto Tlia aHato to dadi aiay
Ikft ua*ai part at tia
Tka towai 1.4*0 toal
aail to pay •*»
to darti a/ay. Me* to
toaftdtlaiaua ahaU
to 100 toM to «Mto to fifty
—-"-— to Me* ii«i«. ~-
aart to
to
and
tun to madium
pad » nodk4« and hu
pail » UntntAUd. )M||ill4Ci»ou*. Mtd
••rf" - -
-. ,-. ^m pail al toonaaan
to NtadkJMdarti fliay. Mn to
-------
Figure 3
Bedrock Topography
Textron Lycoming
Williamaport, PA
I [AM SPORT
Coraur (T««)
POOR QUALlT
ORIGINAL
-------
contrast to the surrounding shales. The buried bedrock surface
slopes downward to the west and southeast from the limestone high.
The bedrock geology in the Elin Park area, as interpreted from
the bedrock well legs and core logs, consists of a thin layer of
weathered lime-rich shale, approximately 5 to 10 feet thick,
overlying the dense shaley limestone of the Tully Member of the
Mahantango Formation. Soft zones in the limestone were encountered
during drilling of both MW-59 and MW-60. These are consistent with
the presence of thin shale units which are often encountered in the
Tully Member. These shale zones were often water bearing and
tended to decrease in number with depth.
Hydrogeology
There are two primary aquifers in the site area; the
overburden and bedrock aquifer systems. The shallow overburden
aquifer is comprised of the Quaternary unconsolidated deposits.
The overburden is a water-table aquifer. There are currently 45
monitoring wells completed in this aquifer in the site area, and
3 recovery wells. Recovery Wells RW-3 (Acid Waste) and RW-l (Tank
Building) are completed across the overburden/bedrock interface.
The Third Street Recovery Well is screened entirely in the
overburden.
The underlying bedrock aquifer consists of upper to middle
Devonian-age rocks, including shales, siltstones, and limestones.
Ground-water occurrence and movement is controlled by secondary
porosity (e.g. fractures, bedding planes). Eighteen monitoring
wells and eight rock cores have been drilled within the bedrock.
The plant deep well (RW-2), located in the test cell area of the
eastern portion of the site has a measured depth of 390 feet and
is presently used as a recovery veil. The Elm Park recovery well
recovers ground water from the shallow bedrock in Elm Park.
The following sections describe the physical characteristics
of the overburden and bedrock aquifers. Because the units have
differing characteristics, the mechanisms governing ground-water
flow and contaminant migration are different. Each unit acts as
a separata aquifer, although they are hydraulically connected.
The locations of the wells described above are in Figure 4. The
construction details of these veils are summarized in Table 3.
Overburden Aquifer
i
Ground water in the shallow aquifer occurs under unconfined
conditions. The depth to ground water ranges from 10 to 27 feet
below grade at the site (August 1990), and 9 to 25 feet near the
WMWA well field. The system is recharged by precipitation and
snowmelt. Seasonal fluctuations of up to approximately 5 feet have
14
-------
Figure
Monitoring Weil Locations
Textron Lycoming
Wllliamaport, Pa
POOR QUALITY
ORIGINAL
-------
T.i Me t
Ill-tl-tt-tl
PccMly
Ul«i*»4
MW4
MWt
MW«
MM I
MW*
MW I*
MW II
MW !•
MW I*
MW M
MW SI
MW n
MW n
MW*I
MWM
MW**
• I
Ml M
Ml II
MtM
U*4*
Ul.lt
U*84
M*4t
M*M
•44*1
•MU
M4.tr
•44 M
M1M
MtM
Ml aa
Ml *»
M*«l
M*M
MJM
•4J II
M*ll
Ml !•
M* IS
•MM
M« 41
Mita
08
HW r
MI C«
HW »'
MOM
M«M
M«M
M«M
M« 14
•M n
Miaa
Ml II
Ml 44
•4* IS
M* 44
M«M
Mao
Ml M
IMM
•4* 4*
M«aa
M«M
Mt 11
M4 11
MtM
Ml t»
Ml 1*
Ml M
M4*l
M2M
M1M
Ml 1*
MtM
Mt tl
Ma M
M1M
Ml 1*
M* It
Ml 24
Ml 12
Ma M
tM M
MtM
Mttl
M* 12
M*4*
n
II
12
t
II
It
II
22
t2t
ait
lit
14
It
Itt
Mt
Itt
M
Mt
It
lit
M •
i*at
Ml
•
U
ai
21
• it
21
• M
21
• U
*2t
lit
at
• 24
n
Mt
• M t
Mt
. M
• Mt
• M
nt
IMI
lltt
II*
1*
It M
ItM
ItM
ItM
It M
ItM
ItM
ItM
MM
ItM
ItM
ItM
ItM
ItM
ItM
ItM
MM
MM
ItM
ItM
Ml «•»•
•!«•*••
Ill (•*•
ItM
MI.M
M>
M)
n ut
Mt 1/21
1/44 4« II
141 !•
Mtl
•2M
21 M
2IM
ItM
21 M
2tM
2IM
12 M
t2M
II M
21 M
24 M
2tM
2t M
MM
2t M
MM
ItM
2tM
21M
IM /t
lit M
lit M
ItM
MM
1/2 M
4t II
Mt tS
t2t II
tit M
t2l 4t
tit It
M« 24
til 41
Mt M
4tl tl
Mt tl
tM tl
tM 4t
t!4 24
til M
tit M
t!2 2t
4M 11
4M tl
• 14 t2
tit M
Mt M
42ttl
4M 12
Ml M
4tt It
144 2«
N)
OQ
>>
M0.MM
-------
OttM* •
•U*l
•I
O
00
ZDZD
oo
MWtl
IM
MWtl
MWM
MM I*
MW II
MM II
MW n
MM 14
444 M
•MM
• IIM
til M
M>
IM II
•M M
HIM
•JIM
Ml M
•Mtl
4M II
Ml II
•MM
IM 14
Ml M
Mt 41
Mt It
tit It
HIM
III It
lit II
Ml 14
• II II
IM It
III It
tilt!
•Mtl
•Mtl
• It II
tM M
•II II
•14 JJ
IM tl
tit II
til II
IMM
• It M
lit M
• 14 II
n n
44 M
III*
It
MIt
11
M
411
M
It
II
Itt
M
II
M
II
M
Itl
It
Itl
M
11
MM
III
41
III
IIM
M
M
M
lit
IM
IM
III
•J
M
11
tt
Mt
11
MIt
14 M
41 It
M
MIt
41
M
Ml
4t
M
11
Ml
• M
n
M
•i
M
• Mt
n
Ml
4t
41
MM
441
U
n i
• IM
43
M
M
140
IM
IM
IM
tl
41
44
M
41 t
M
ItM
MM
II M
It M
ItM
ItM
It M
It M
It M
It M
MM
It M
ItM
ItM
MM
tt M
It t*
It M
It tt
It M
ItM
It M
It M
IIM
ItM
ItM
ItM
ItM
M Hptw*
M »•»•">
ItM
MM
IIM
41 M
ItM
ItM
IIM
ItM
ItM
1% M
It It
• t tt
4114
ItM
41 It
41 M
MM
41 M
4t M
14 M
I/ M
IIM
41M
II M
M M
M M
14 M
M M
4t M
41M
tt It
44 M
41 M
II It
tl t4
41 M
MM
ttM
I4t M
IM M
IJt M
IMM
tIM
4)OO
4t M
10 00
41 40
1*00
tI4 It
4lt II
4M It
4t4 14
Mt
4lt t4
4M It
411 It
411 M
til M
4M tl
tit II
til II
4t4 41
4lt 41
tit !•
tit 41
tit tt
4tt tl
4M 4t
411 It
4lt II
4M M
414 It
4lt tt
M4 It
411 M
411 14
4M 41
411 41
M4 41
411 tl
414 tl
1/t t*
411 tl
4(4 4t
411 II
4M It
444 M
M4 IS
-------
l.il.le 3
Mt L
ra*
M4«l
Ml II
Ml II
M»M
MXM
tMM
MIM
• MM
• I* It
M»M
• UM
•MM
*M4I
•MM
M**l
M*«l
M4M
•4BM
•It4«
Ml 14
M*U
•M 14
•M M
• IBM
•MM
•MM
• UM
M«M
MAM
M«M
•MM
Ml n
M4 M
M4*l
M* II
U4*«v«l
Mft «•
It M
M • M
M* »•
MM MM
41 M
IIM «IM
M 43
M IM I
IM« lit*
MS • ll«
IM 14*
IM !•
IM IM
lit IM
M •!
MM
I«M
MM
MM
• •M
IBM
• •M
<•/**•*
19
II I
UM
MM
UM
UM
• IM
ItM
MM
MM
••It
tlM
• I •»
41 M
MM
• tM
IM /•
lit M
II«M
I4«M
IMM
IMM
IUM
• f M
4t/ •!
4*4 /t
4M ai
44B •/
4M ••
4/401
*>/ M
411 24
4M«2
411 tl
MOM
42tO)
4M 12
IM 41
411 02
414 •!
!/• •»
421 •!
14)1
(Ml
|M
(MT)
••m
TJ
08
•i m
oo
zC=
>>
-------
been observed in the water table beneath the site at veil w-i
where -he overburden unit is thin. Ground water in the shallow,,
aquifer flews through interstitial voids in the sedi-ent, primarily^
in a southerly direction with =inor components toward the southwest
and southeast /Figure 5). The hydraulic gradient in this area is
largely controlled by the surface and underlying bedrock topography
'see Figure 2;.
Weil yields in the valley fill deposits in the williansport
region average 300 gallons per minute (gpn). The highest yields,
up to 2 , 300 gpm, are obtained from wells drilled near the
confluence of south-flowing streans and the Susquehar.na River,
where overburden deposits are relatively thick. The hydraulic
gradient has been measured at approximately 0.02 feet/foot in the
vicinity of the plant, but this gradient flattens to the south
before reaching the Susquehanna River due to the presence of a
bedrock high in the subsurface beneath the plant.
The point of lowest hydraulic head in the area is the
Susquehanna River. Lycoming Creek and the Susquehanna River are
the boundaries of the hydraulic systems and tend to act as points
of ground-water discharge in the regional ground-water flow
pattern. Ground water in the overburden aquifer moves primarily
south toward the Susquehanna River. The ground-water flow velocity
increases as it approaches the river as indicated by data obtained
from recovery well aquifer testing. Lower hydraulic conductivities
near the plant probably limit the natural ground-water flow rate
to less than one foot per day. Hydraulic conductivity is higher
at the WMWA well field, where natural ground-water flow rates are
on the order of five to ten feet per day.
Relationship between Lycoming CreeJc and Overburden Aquifer
During the RI investigation, efforts were made to better
understand the hydrologic relationship between the overburden
aquifer and Lycoming Creek in the site area. A total of five
piezometers were installed in Lycoming Creek, one at each of the
five surface water and sediment sampling stations. Streamflow
measurements ware takan at each of the stations to obtain discharge
measurements along various portions of the stream. Elevations on
five of tha bridges vara also surveyed and marked for the
collection of stream alavations along Lycoming Creek.
The stream flow and piezometer data generally indicate that
the upper' portion of tha stream, abova the High Street Bridge
(Station 5), is a gaining stream (i.a., receives ground-water
discharge). In contrast, between Station 4, near tha Memorial
Avenue bridge, and Station 2, near Third Street, Lycoming Creek
appears to be a losing stream (i.e., recharges the overburden
aquifer) . This change is a response to pumping from the Third
Street recovery well which pumps continuously at an average rate
19
-------
Figure 5
Water Table Surface
Overburden Aquifer
August 1990
Textron Lycoming
WILLIAMSPORT
POOR QUALITY
ORIGINAL
800
-------
of 900 to 1CCC crpa. Since the overburden aquifer north of thf
Third Street Recover/ Well cannot provide the total voluae ~c:
ground water puaped oy this well, the additional water flowing to
the well comes frcm Lyccair.g Creek and the overburden deposits
located northwest of this well. Lyccair.g Creek becoaes a gaining
stream again south of Station 2 as it leaves the area influenced
by the recovery well and approaches the Susquehanna River.
Water levels in the lower portion of Lyccming Creek are
affected when the WMWA wells are pumping, as interpreted fron past
WMWA water level data. This suggests that the lower segr.ent of
Lycoaing Creek becor.es a losing streaa in response to the pur.ping
of the WMWA wells. The WMWA wells were not in operation at the
tir.e that the streaaflow and piezcaeter measurements were taken.
Bedrock Aquifer
Ground-water flow through the bedrock aquifer is important in
developing an understanding of contaminant migration in the site
area. Ground-water movement in the bedrock is not controlled by
shallow hydraulic gradients as in the overburden, but by secondary
features such as solution features, jointing, fracturing, and
orientation of bedding planes. Though southeast is the direction
of the hydraulic gradient within the bedrock aquifer, the direction
of ground-water flow is primarily southwest, along the strike of
the bedrock. This is based on both the recovery test and water
quality data. Water-level measurements for the bedrock monitoring
wells from August 1990, are presented in Figure 6. The depth to
ground water for the bedrock wells on and off the site property
(October 1990) ranges from 17 to 28 feet below grade.
Ground water yields in the bedrock aquifer are variable,
ranging from less than 1 gpm to about 40 gpm from the bedrock
beneath Elm Park. Area wells drilled in the shales of the
Marcellus, Mahantango, and Harrell Formations tend to yield
moderate supplies of water. Wells are typically constructed with
shallow casings and large, open intervals to intercept as many
water-bearing zones as possible. Yields range from 12 to 355 gpm
in industrial and public supply wells in the area. The average
yield is 52 gpm. The median well depth for these formations is
137 feet. Siltstones, which include the Brallier Formation, tend
to be the area's poorest aquifers, with a median yield of 6 gpm
and median depths of 153 feet for domestic wells and 400 feet for
non-domestic wells.
t
The Tully Member of Mahantango formation, which underlies 60
percent of the plant, consists of variable thicknesses of
interbedded limestone and calcareous shale. These units are
relatively impermeable due to their fine-grained, compact nature,
however, the lime-rich units are susceptible to dissolution and
exhibit numerous solution features, especially within the upper
21
-------
Figure 6
Bedrock Aquifer Ground Water Levels
27 August, 1990
T«xtron Lycoming
WHIIamsport, PA
WILLIAMSPORT
800
NHVKI
POOR QUALITY
ORIGINAL
-------
weathered zcr.e. This weathered zone exists where the lime-rich
units cf the Tully underlie, ar.d are in contact with, tht
overburden. The solution features present within the Tully member
do not occur in the adjacent ncn-calcareous shale ur.i'ts, but
fracturing, jointing, and bedding planes are cordon to both types
cf bedrock and can be primary routes of ground-water flow.
During the Chester investigations, packer testing was
conducted on boring 55A to determine permeability at varying depths
within the upper 50 feet cf the Tully member cf the Mahantango
Formation. These tests indicated that hydraulic conductivities
range from 1.0 < 10'3 centimeters per second close to the bedrock
surface to less than 1.0 x 10'* centimeters per second deeper in the
bedrock .
Relationship between Overburden and Bedrock Aquifers
Vertical head relationships between the overburden and bedrock
aquifers were examined from water-level data collected during
November 1939, August 1990, and the recovery test conducted in
September 1990. The overall vertical head differences in the study
area were small with the exception of the wells in Elm Park area.
An upward vertical gradient is consistently measured at well nest
MW-60 and MW-32. This suggests that the bedrock aquifer discharges
into the overburden aquifer in the vicinity of the wells. The fef
overburden wells along the bedrock high limit the ability t~
further delineate this discharge area, however, contaminant- trends
indicate that ground water most likely discharges from the bedrock
high into the overburden beneath Elm Park. The operation of the
Elm Park Recovery Well may also help induce the upward gradient in
this area, though it is not possible to evaluate this effect with
the data collected to date. However, the concept fits with the
interpretation developed for ground-water flow from the bedrock.
Nature and Extent of Contamination
Since 1985 whan VOCs were first identified in ground water,
numerous sampling events have been completed beginning with the
investigation by Chester, followed by bi-monthly sampling until
1933, at which time quarterly sampling was initiated and continues
to the present. The two RI sampling events were completed during
the routine quarterly sampling program.
t
The comprehensive ground-water sampling and analysis conducted
during the Chester investigations indicated the presence of certain
vocs and metals in the ground water near the old WWTP. Chester's
initial ground-water sampling event included Priority Pollutant VOC
analysis by GC/MS analytical methods and selected inorganic
compounds. The primary compounds of VOC contamination found wer
23
-------
TCE and DCE. Subsequently, the quarterly ground-water monitoring
focused on these compounds.
The November 1939, sampling event conducted for the Phase I
RI included the Target Compound List (TCL) of VOCs and semi-VOCs,
Target Analyte List (TAL) Metals, Pesticides, PCBs and Cyanide with
Contract Laboratory Data packages. This sampling confirmed the
original findings. Since TCE, DCE and to a limited extent vinyl
chloride and hexavalent chromium have been confirmed as the primary
contaminants of concern, the Phase II RI sampling (August 1990) and
quarterly monitoring events include analyses for these compounds.
The voluminous ground-water quality data base identifies the
presence of a combined TCE-DCE plume in the overburden aquifer that
has maintained a stable configuration since it was first identified
in 1985. Additional overburden monitoring wells installed during
the Phase II RI have helped to establish the perimeter of the
affected area. Surface-water sampling of Lycoming Creek has
identified no discernible impact on surface-water quality.
The Phase I RI included a comprehensive ground-water sampling
event conducted in November 1989. Ground water from all monitoring
wells installed during the Phase I RI, and 15 of the existing
monitoring wells was analyzed for the full TCL/TAL list of
compounds including PCBs/Pesticides and Cyanide, and all of the
remaining wells were analyzed for the identified contaminants of
concern; TCE, DCE, and vinyl chloride. Samples for TAL analyses
were both filtered and non-filtered.
The Phase II RI included the sampling of 49 monitoring wells
and was conducted after the completion of the Phase II field
investigation. Ground water from all monitoring wells installed
for the Phase II RI, all bedrock monitoring wells, and selected
overburden wells were analyzed by EPA Method 601 for the identified
contaminants of concern (TCE, DCE, and vinyl chloride). In
addition, dissolved hexavalent chromium was added to the analysis
for monitoring wells MW-3R, MW-4, MW-5, MW-18, MW-31, MW-32, MW-
33 and MW-34. MW-3R and MW-18 were analyzed for both filtered and
unfiltered hexavalent chromium.
Tables 4 and 5 present the results of the Phase I and Phase
II ground-water sampling events for TCE, DCE and vinyl chloride.
Ground-Water Quality in Overburden Aquifer
i
The evaluation of data from the Phase I (comprehensive) and
Phase II (abbreviated) sampling events confirms that the primary
organic contaminants of concern in the overburden aquifer are TCE
and DCE. Vinyl chloride is present beneath the site and, to a
lesser extent total chromium and hexavalent chromium are present
24
-------
fa*
1.1 1. 1 i.- 4
I Ml QiouAd ••!•«
Evml
Facility
Four* OUMIM UM
*•«• M MM Tcntemi L yearning
72) •)•••!
AAAMfcAt L.6£4%AftttA
tAMfcAt QfeAt
Uftlit
ValalUt OfAMiM
lilAl»Ui*«Miyto*«
VlAvt Chi*«U*
MW-I
!!/•/§•
MA /I
• t
ItOO
«20
UW 2
!!/•/••
Mfl/l
•/!
370
••0
110
UW 4
1 !/•/••
pfl/l
17
§2
00
taoo
0
UM-7
1 !/•/•§
Mfl'l
1 b
/O
0 0
ii/ii/ti
y w »D
!!/•/•§
yw-ii
1 !/•/••
II
ii/7/at
UWI2
1 !/?/••
13
1 !/•/•§
IU1U
*•0
U 100
. M»
UW 21
I 1/8/>»
_iiflli_
/ooo
4:10
I/O
-------
e A (i-ont '.I)
Pttasa I Rl (bound Watar SaatpMnfl Evanl
Taitoon Lycomlng
Wllllanapofl FacUlly
Fouflh Ouartaf IMS
Analytical RaauMa lot lAenModng WaMa at lha Taikon Lycoating facility. WUilaaupoit. PA.
723-03-00-01
aftAflata^a^at aL a^at Aatta^A
Ama^^A^^h ^^B^B^B%
UaJU
Vataatta OrfMatoo
TftdOoioaUtytana
VWtvt CMo«i4a
Mw-ta
|t/IO/t»
Hfl/l
1ft
ISO
-------
T.ililc 4 (i-ont'.l)
?*•»• I Ml OiouMl W*t«f
Event
F«4Jr1ll
IM0
72) •! •• 01
. PA
~o
0
OO
:D ;D
srsr-
0*44 •
VUyi CMofirf*
MW-I4
Ml/1
!••
>
r- l~
r __
1
-------
TABLE S
Ph*«« M Rl (bound WaU« S«»pUog Ev«nl
TABUOA LycoMlng
WUUsMSpofl Facility
Thfcd OUMIM 1MO
»4 Ih* T«ib
ins^r**
UfUU
fcJ^^^^Afy* ^tOMUUB^^BBk
1 2 • B^B^^BB^&f ^^B^^^BttB^B^B^Bi 4^AA^^fc
Vinyl CMMtd*
y w 2
MB/I
<05
y W 3N
8/28/88
Vfl/l
54
280
<50
y w 4
MB/I
25
110
<50
y w s
va/l
1300
280
170
y w 8
8/28/88
Vfl/l
700
2100
37
yw 7
8/28/80
Mfl/l
47
-------
TABLE S (Cent)
M M (bound W.I* tUMpMng Ew*nl
WIIIUM«f>o«l Facility
Ifckd Ou*JU< lit*
A4*ulU tof Mo«UlOfti»a W«4ta «4 UM l«ito
-------
TABLE S Conl.)
Phaaa M M Ground Wal«* Sampling Event
TaiUon Lycomlng
WUIIaMapoil Facility
Tnkd OuMtM 1690
Analytical lloauMa »M ilonHoring Walla al lha Taitoon Lycoatlng FacllMy, WUIUatspocl. PA.
72) 63 01 01
•ittit*
MW ••
y w
yw-7i
yw-72
6/26/60
UW 74
6/26/60
••/I
Hfl'l
tffl/l
Pfl'l
Kfl/l
MO/1
TticMataailiylann
Vinyl ChkMkta
09
-------
beneath the western end of the site. A few ether organic comcour.ds
were detected in a few wells at trace concentrations.
The conf iguraticr. cf the cer_bir.ed TCE-DCE plur.e as interpreted
fro- the NcverJ:er 1339 (Phase I RI) ar.d August 1990 (Phase II Rl)
sanplir.g data, are presented in Figures 7 and 3 respectively.
These figures identify 3 areas on the site that have elevated
concentrations cf these compounds.
The first area shewing elevated concentrations is the area
around monitoring wells MW-9 and MW-20, located at the eastern end
of the site. Both cf these wells were sampled in 1985 by Chester
and the ground water contained combined TCE-DCE concentrations of
approximately 1,000 ppb to 2,000 ppb. These wells have been
sampled guarterly since 1933. In early 1939, increased TCE and DCE
concentrations were observed in both wells. Concentrations in MW-
9 have increased to 17,000 ppb TCE and in MW-20 to 8,300 ppb TCE.
Concentrations of DCE have also increased in MW-9 from 138 ppb to
310 ppb and in MW-20 from 116 ppb to 360 ppb. No explanation for
this increase in concentrations is apparent, since these wells, in
particular MW-20, are not downgradient from any suspected source
area at the site. MW-9 is located close to a former drum and
bottle storage area and the former rail line. It is noted that the
downgradient off-site ground water monitored by wells MW-12, MW-
29, MW-35 and Phase II well MW-74 shows little or no effect from
this high concentration area, indicating that the contamination
from this area has not migrated off site in the southeast direction
to any significant extent.
The second area showing higher concentrations is located in
the central portion of the site in the vicinity of MW-5, MW-21,
and MW-50. This area is near several identified areas of concern,
including the "dry well" and the chipster sump. The TCE-DCE
concentrations in ground water in MW-5 were detected at a peak
concentration of 67,200 ppb in August 1985. The combined
concentrations of TCE and DCE in ground water at MW-5 have
decreased since the recovery veil began operation in 1936, to
combined TCE-DCE concentrations of 1,520 ppb in the August 1990
sampling. MW-21 data has shown wide fluctuations of combined TCE-
DCE concentrations since the peak combined value of 12,350 ppb in
May 1985. The data for this well indicate an overall decreasing
trend in th« concentration of TCE (11,100 ppb in May 1985 to 830
ppb in Nov«mb«r 1989) and an increasing trend in the concentration
of DCE (1,750 ppb May 1985 to 7,000 ppb in November 1989). Ground
water in monitoring well MW-50 on the other hand had a peak
combined yalue of 53,000 ppb in October 1987; present combined
values are 16,400 ppb.
The third area of higher concentrations is located beneath
the western portion of the site near the old WWTP, the old Human
Resources Building and the Oliver Street storm sewer. The
monitoring wells with the highest TCE and DCE concentrations in
31
-------
1.4OO
Figure 7
TCE-DCE Overburden Plume
,. Concentration in ppb
November 1989
Textron Lycoming
W«ft Third StTMl \ I
Rccowry W«
-------
Figure 8
TCE-DCE Overburden Plume
Concentration in ppb
August 1990
Textron Lycoming
SCO
, rcz-oca
POOR QUALITY
A I
-------
this area are MW-3 and MW-13. Samples from MW-ia show decreasing
concentrations of TCE (high of 60,400 ppb in June 1985 decreasing
to 1,300 ppb in August 1990), and DCE (436 ppb high in May 1935
decreasing to less than 20 ppb in August 1990), since the
initiation of ground-water recovery at RW-3 in this area in 1936.
The 1935 peak TCE-DCE combined concentration of 60,856 ppb in MW-
13 has decreased (August 1990) to a combined TCE-DCE concentration
of 1,300 ppb. Concentrations of each compound in MW-3 have
fluctuated over time. The concentration fluctuations in this well
appear to be seasonal, with the highest concentration typically
reported in the winter quarter. Ground water in MW-4, located less
than 200 feet east of MW-13 shows lower TCE-DCE concentrations in
comparison with MW-13 (e.g. August 1990, MW-4 at 135 ppb). This
is possibly due to the configuration of the bedrock surface beneath
this portion of the site which may affect the direction of ground-
water flow and contaminant migration in this area.
These three areas can be thought of as separate areas from
which the contaminants would migrate. However, further
downgradient in the overburden aquifer, where the bedrock elevation
decreases and the aquifer thickens, the three plumes commingle.
The TCE-DCE plume in the overburden, depicted in Figures 7
and 8, shows that the off-site portion . of the plume migrates
southward from the central and eastern portions of the site. This
plume extends toward the south where it is intercepted by the
capture zone of the Third Street recovery well. However, low
levels of these contaminants have been detected in samples
collected from the public supply wells that are located on the west
side of Lycoming Creek.
As part of the Phase II RI, six additional overburden
monitoring wells were installed to help better delineate the
perimeter of the overburden plume. Based on the August 1990 data,
upgradient wells MW-36, MW-2 and MW-11 represent background water
quality levels since TCE-DCE and vinyl chloride are not reported
above method detection limits. The eastern edge of the plume is
monitored by MW-35 (54.1 ppb) which is 250 feet due east of the
site property line, MW-12 (2 ppb) located 450 feet southeast of MW-
9, MW-74 (less than 0.5 ppb) located on Memorial Avenue and MW-73
(4.5 ppb) located north of the railroad tracks approximately 1000
feet southeast of the site.
The western perimeter of the plume is defined by MW-69 (0.9
ppb) located at the far west end of the site, MW-70 (0.7 ppb)
located 500 feet west-southwest of the site, and MW-71 (1.2 ppb)
in Memorial Parfc, approximately 1000 feet southwest of the site.
The configuration of TCE and DCZ plumes in the overburden are
similar, but differ in detail in specific areas of the plant. The
general shape of plumes for these individual contaminants has
34
-------
remained similar between the Phase I and Phase II RI samel ir.cj
events.
Figure 9 shews the overburden TCZ plume from the Phase if
August 1990 sazpii.-.g event. As discussed above, elevated TCZ
concentrations are present at three distinct areas beneath the site
boundary. These occur around: 1) the old WVTTP; 2) the central
portion of the site around MW-50 and MW-21; and 3) in the
southeastern corner of the eastern-most parking lot centered around
MW-9. The three areas of elevated TCE concentrations appear to
correspond to suspected contaminant source areas at the site with
the exception of the area around MW-9, the source of which is not
known. The eastern-aost zone appears to be associated with TCE
detected in MW-15, MW-52, and MW-25. The plume from this area
extends to the south.
DCE is a degradation product of TCE, and as such the
configuration of the DCE plume mimics the TCE plume to a certain
extent, as depicted in Figure 10 from the Phase II ground-water
sampling event. Though similar to the pattern observed for TCE,
the DCE plume is subdivided into two distinct regions of high
concentration beneath the site. . One area is in the vicinity of
the old WWTP, centered around MW-3 (now MW-3R) to the north of the
old WWTP location. The other area of higher DCE concentration is
in the central area of the site around MW-50 and MW-21.
.The zone of high concentration of 54 ppb around MW-3 is inucv
more localized than the zone of TCE in the same area and is OL
limited extent. The zone of high DCE concentration in the center
of the site extends to the east-southeast, possibly connecting with
a zone of high DCE levels in MW-8 adjacent to Building 2, and
further eastward in the vicinity of MW-9.
DCE concentrations are primarily limited to the central
portion of the overburden plume, and do not extend to the outer
fringes, as evidenced by the results from the Phase II monitoring
wells.
Vinyl chloride was detected at elevated levels in six of the
on-site overburden wells during the Phase I RI sampling event.
The highest values were detected beneath the center of the site
property in ground water from wells MW-50, MW-21 and MW-5, with
concentrations of 520 ppb, 170 ppb and 310 ppb, respectively.
Ground water from MW-3, located on the west side of the site, had
a concentration of 150 ppb. Vinyl chloride was also detected at
50 ppb and 28 ppb at monitoring wells MW-6 and MW-8. Figure 11
shows the. configuration of the vinyl chloride component of the
contaminant plume from the Phase I RI data. Vinyl chloride was
not detected in any off-site overburden wells.
Analysis of ground-water samples from the Phase II RI sampling
event (August 1990) showed vinyl chloride in monitoring wells
35
-------
Figure 9
TCE Plume Configuration
Overburden Aquifer
August 1990
Textron Lycoming
wi IAMSPORT
POOR QUALITY
ORIGINAL
-------
Figure 1 Q
DCE Plume Configuration
Overburden Aquifer
August 1990
Textron Lycoming
POOR QUALITY
ORIGINAL
-------
Figure 11
Vinyl Chloride in Overburden Monitoring Wells
7-10 November 1989
Textron Lycoming
Wllllamsport, PA
WILLIAMSPORT
* AMM AMBMry VIM
80C
POOR QUALITY
ORIGINAL
-------
5 and MW-6 at concentrations of 170 ppb and 37 ppb, respectively.
Mo other samples from the overburden shoved concentrations above
Very few additional VCCs were detected in either the on-site
or off-site wells sampled for the TCL/TAL list. Twenty samples
from the Phase I ground-water sampling event were analyzed for'the
entire TCL/TAL list of compounds to determine whether there were
other compounds of concern present. The compounds, 1,1,1-
trichlcrcethane, toluene, 1,1-dichloroethylene and 1,1-
iichioroethane, were detected at low concentrations ranging from
3 ppb to 35 ppb in en-site monitoring wells MW-6 and MW-3.
Ground-water samples from MW-3 and MW-13, located near the
old VV~WT?, were the only en-site wells to contain elevated levels
of dissolved metals. MW-3 contained levels of cadmium (959 ppb)
and total chromium (4,500 ppb) and hexavalent chromium (5,000 ppb) ;
MW-13 showed concentrations of both total chromium (9,250 ppb) and
hexavalent chromium (10,000 ppb). Off-site well MW-32, located
north of Fourth Street in Elm Park, contained a concentration of
lead at 74 ppb.
Hexavalent chromium (dissolved) was analyzed in subsequent
sampling events to better delineate the extent of this compound in
ground water. Samples from MW-3R (replacement well for MW-3), MW-
4, and MW-13 showed hexavalent chromium at 6,900, 18, and 9,200
ppb, respectively, during the August 1990 sampling event.
Monitoring well MW-31, located off-site approximately 500 feet
south of the old WWTP, showed hexavalent chromium at 102 ppb during
the August 1990 sampling event.
Ground-Water Quality in Bedrock Aquifer
As with the overburden aquifer, the primary VOCs in the
bedrock aquifer are TCE, DCE and vinyl chloride. Figures 12 and
13 show the combined TCE and DCE concentrations detected in ground
water from the bedrock wells for the Phase I and II sampling
events, respectively.
The highest concentration of these compounds has been detected
in the on-«ite bedrock monitoring well MW-62 located adjacent to
the southeastern plant property along Memorial Avenue. This well
is nested with overburden monitoring well MW-8 and bedrock
monitoring well MW-8D. The August 1990 sample from MW-62 showed
a TCE congentration of 13,000 ppb, and DCE at 8,400 ppb; a decrease
from levels for the compounds of 19,000 ppb and 13,000 ppb,
respectively, from the November 1989 sampling event. Other VOCs
detected in this on-site well in November of 1989, included vinyl
chloride at 250 ppb, 1,1-dichloroethylene at 71 ppb, 1,1-
dichloroethane at 47 ppb, and 1,1,1-trichloroethane at 62 ppb.
39
-------
Figure 1 2
TCE - DCE in Bedrock Wells
7-1 ONov«mb«r 1989
Ttxtron Lycoming
Williamsport, PA
WI IAMSPORT
400 200 0 400 800
POOR QUALITY
ORIGINAL
-------
Figure 1 3
TCE-DCE In Bedrock Wells
Concentration in ppb
August 1990
Textron Lycoming
litl) rca-oca
Scat« fi
POOR QUALITY
ORIGINAL
-------
MW-8D monitors a shallower bedrock interval than adjacent
monitoring well MW-62. In November 1989, most of the same
compounds detected in MW-3D were detected in MW-62, but at lower
concentrations. TCE was detected at a concentration of 3,600 ppb
and DCE at a concentration 3,400 ppb. TCE was detected during the
Phase II sampling event at a concentration of 3,800 ppb and DCE at
a concentration of 2,600 ppb.
The August 1990 sample from on-site bedrock well MW-23 (which
is constructed similar to MW-3D) contained low concentrations of
TCE and DCE, at 210 ppb and 9.9 ppb, respectively. This well is
located 350 feet west of the MW-8D well nest. TCE and DCE levels
have also remained generally consistent in this well since late
1987, after reaching a peak in December 1986.
The August 1990 ground-water sample from on-site bedrock well
MW-63 contained TCE and DCE at concentrations of 2,900 ppb and 230
ppb, an increase from values of 800 ppb and 61 ppb, respectively,
detected in the wells during the first sampling event in November
1989. Lew concentrations of only a few other compounds were
detected it that time. This well is located roughly 400 feet
northwest (downdip) of MW-23.
Analysis of samples from the off-site bedrock wells showed no
anomalous values with the exception of MW-53 which is located near
the Third Street Recovery well and nested with MW-25. The highest
TCE and DCE concentrations in this well were recorded in November
1989, at 37 ppb and 15 ppb, respectively. These concentrations
decreased to previous levels by the January 1990 sampling event and
have since increased. Contamination in the bedrock continues to
be detected in the Elm Park monitoring wells. Samples from the
newly installed bedrock wells in this area screened at a lower
elevation show low to non-detectable concentrations of the
compounds of concern. MW-59 shows no compounds above the method
detection limit, and MW-60 has a concentration of TCE at 0.9 ppb
and DCE at 1.6 ppb. This indicates that contaminants have not
appreciably migrated to the deeper bedrock in the Elm Park area.
The installation of the Phase II bedrock wells have helped
delineate the extent of the bedrock contamination. TCE and DCE
were detected in MW-65, at 50 ppb and 61 ppb, respectively. This
well was drilled off-site along the line of strike from MW-62.
This was the highest concentration of TCE-DCE detected in any of
the Phase II bedrock wells, and is consistent with, and lower than,
the concentrations of TCE-DCE found in upstrike bedrock wells MW-
80, MW-23, and MW-62. Bedrock monitoring wells MW-64, MW-66, MW-
67 showedi TCE-DCE levels less than the analytical method detection
level of 1.0 ppb for the August 1990 sampling. This provides
evidence that detectable levels of these compounds have not
migrated within the bedrock aquifer south and southeast of the
site.
42
-------
Dissolved petals concentrations in the bedrock wells were not
elevated (relative to the other wells saspled) with the excect'-'c-
of barium, detected at 3,500 ppb and 930 pcb in MW-59 and MW-22*'
respectively, in Ncveaber 1939.
Dense Non-Aqueous Phase Liquid (DNAPL)
No evidence of DNAPL contaaination was observed during either
the Phase I or Phase II drilling programs. Sediaent samples
collected with a Xeaaerer saapler from the bottom of three
monitoring wells (MW-61, MW-62, and RW-2) showed no visual evidence
of a DNAPL. 3y observing the bottom sediments after they had been
allowed to sit for a period of tiae, DNAPL, if present, aay be
observed as beads of product in the sediment. These three wells
were selected because they were either open-hole wells located in
an area were DNAPL could occur or were wells where past sampling
events had indicated high concentrations of TCE and DCE. MW-62 is
also the deepest accessible monitoring well on site.
A review of past concentration data from all monitoring wells
was conducted. The concentration of TCE in well nest MW-8, MW-
3D, and MW-62 increases with depth. MW-62, one the deepest bedrock
wells in the study area, shows the highest TCE concentrations
detected. The concentrations of dissolved DNAPL components
relative to their solubility are often used as indicators for the
presence of a DNAPL. Concentrations on the order of 10 percent of
the solobility are typically expected if a DNAPL were present. The
solubility of TCE in water is 1,100,000 ppb. The highest TCE
concentration presently detected is 19,000 ppb in monitoring well
MW-62; less than 5 percent of the solubility of TCE.
Thus, the evidence does not indicate that there is a mobile-
phase DNAPL that is potentially recoverable. It appears more than
likely that if non-aqueous phase liquids are present, they are
located on-site and represent a residual contaminant source, but
one that is immobile and containable.
Community Well Investigation
An inventory of the identifiable residential, commercial,
industrial, and public-supply water wells within an approximate 3-
mile radius of the study area was conducted to identify potential
ground-water receptors. Available information concerning well
owners, well depth, use of the well and the location, the geologic
formation ^n which the well was finished, date drilled, and whether
the well is presently in use, was obtained and is presented in
Table 6.
A total of 35 wells were identified within an approximate 3-
mile radius of the AVCO Lycoming Site. Eleven are identified as
43
-------
.33.<2 T
W«M tovw.tory
Taxtron Lyeetnin^, WlilUmaport Facility
Own«r
in f»«t
Oat*
Drilled
«•«•« UM*
Uiwt Monitor** OUitne*
3ri«ni«iioni
29
31
32
33
34
35
36
37
31
39
49
SO
11
«•
72
10
it
14
219
220
221
321
349
41 1
412
413
574
S7«
S9«
MAMA
'umturvv
St»w*rt Arttfloai t
StMicn Arofleal i
Co.
22
3«
•00
23
140
SO
244
1M
• 2
tM
101
1 1 1
2t
21
lit
iTf
3«
30
30
2t
32
4«
4«
4«
ICO
no
It
40
41
1*0
20«
it3«
itOO
1«32
it20
192*
193*
193*
1934
197J
192*
193«
1929
1972
1972
1942
1*7)
1973
1973
1974
1971
197*
1971
1971
194)1
194)1
197»j
1971
1
Alluvium
Alluvium
Alluvium
Oawoman Bedrock
Alluvium
intfuttrtcl
industrial
in«u«tnai
Ovenuy S«drec*
Alluvium
Munan l«droc*
SBunan
Alluvium
Alluvium
Dram
Or«n
Drain
Commercial
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
S 800 •«•< 5
S 700 >••( SS«v
«.700 'Mt SSW
4 900 *Mt S
S MO '•«< SS
$900 'MI S6
12.100 'Ml SS
1 1 200 *Mt SE
I 440 to«t SE
13 soo f««<' e
13.900 >•*•( SSW
14 4OO fVM SSW
9 300 f»*t S
«.3oo
9.700
9 900 'Ml NW
« 300 %«t SNvy
4 300 'Mt S
5 WO f
S.400
4SOO
9.300
9.300
9.300
13.000
14.400
13.200
9.100
10.700
9.300
9.700 I«M
11.200 IM( NC
14*00 IWI S<
13.900 %« SC
SSW
SSW
< S
< S
i S
< S
SW
saw
NW
N
NNW
S
S
NO: No I
POOR QUALITi
ORIGINAL
-------
Su.Tjr.arv of Site Risks
The objective of this section is to estimate the potential
for adverse health or environmental effects incurred by human or
ecological receptors exposed under the exposure scenario
established in the RI. This section summarizes the Risk Assessment
report.
In order to estimate the human health risk, the risk
assessment focused on the following: (1) the contaminants detected
during the RI at the Site; (2) the potential environmental pathways
by which populations might be exposed to compounds released from
the Site; (3) the estimated exposure point concentrations of the
compounds of concern; (4) applicable or relevant and appropriate
requirements (AJRARs), criteria, and advisories; (5) the estimated
•intake levels of the compounds of concern; and (6) the toxicity
values of the compounds of concern. The level of risk that the
Site poses to human health was then quantified.
Human Health Risks
Indicator Compound Selection
The contaminants identified in the RI are comprised of a
diverse group of compounds with different toxicological properties.
The extent of contamination varied widely in concentration and
occurrence throughout the site property. Moreover, some
contaminants represent a greater potential for risk to human health
and the environment than others because of the differences in
toxicity, capacity to migrate to receptors, concentrations present
and likelihood of exposure concentrations at levels high enough to
pose human health and environmental risks.
The considered compounds (contaminants of concern) selected
for each scenario or medium at the AVCO Lycoming Site are presented
in Table 7. These compounds are believed to represent the majority
of carcinogenic and non-carcinogenic risks associated with the AVCO
Lycoming Site. TCZ, DCS, vinyl chloride, toluene, and
tetrachloroethylene were the compounds considered in the Risk
Assessment's evaluation of exposure from the air strippers. The
rationale for the selection of the above considered compounds is
presented in the Risk Assessment Report for the AVCO Lycoming Site.
45
-------
T.ible 7
Summary ol Considered Compounds
In Each Area
Textron Lycomlng
WUIIamsport, Pennsylvania
Scenario A
Effluent WMWA Wefl Field
Ground Water
Wefte
Scenario B*
Third Street
Ground Watar
Untreated
Scenario C
Off-Site Overburden
Ground Water -
Elm Part Area
Scenario O
On-SJte Overburden
Ground Waler - Plant
Southern Boundary
Scenario E
Off-SJie Bedrock
Ground Water
Mona Detected
1.2 Dtttooetiytone (total) 1.2 Dirtitoroethytene (total) 1.2 Dichloroelhylene (total) 1.2 Dfchloroeihylene (total)
Trfcttofoelhytana Trichtofoelhvtene Trichtoroethylena Trichkxoelhylena
Lead
Barium
BeryMum
Manganefte
Vinyl Chtonde
Cadmium
Vinyl Chloride
Qarium
1
Scenario F
Oo-StU Bedrock
Ground Water
.2 Dtchtofoethytene (total)
TricMoroethytene
.^ny) Chtonde
Scenario G
Chromium Area
In Ground Water
Hexavatent Chromium
Soto
(0-6 tee* beneath
paving)
Toluene
Trichloroelhylene
Lycomlng Creek
Surface Water'*
1.2 Dichloroelhylene (total)
Trichtoroelhytene
Manganese
Lycomlng Creek
Sediment
Lead
Ren/o(a)pyrene equivalent
08
15:0
OO
•Indudjaajinfluenl data tor WMWA well lield
"IncMHk storm sewer sample coHecled on site
-------
Exposure Pathways
This step in the risk assessment process involves determininc
the potential routes of exposure to the human population, the
estimated concentrations to which the population is exposed, and
the population at risk. Based on the information collected during
the RI, the Risk Assessment identified 11 exposures scenarios that
were associated with ground water, soil, surface water, air and
sediment at and around the AVCO Lycoming site.
The RI shewed that en-site soils and ground water at the AVCC
Lycoming Site contain moderate to high levels of organic and
inorganic contaminants. The two major inorganic constituents found
in the soils are lead and chromium. Lead was detected at
concentrations of 169 ppm and 135 ppm at the eastern end of the
site property. The highest chromium concentrations detected were
437 ppm near the center of the site and 1,120 ppm beneath the Human
Resources building, which no longer stands. The shallow ground
water in the overburden in the western section of the site contains
total chromium and hexavalent chromium at concentrations of 9,250
ppb and 10,000 ppb, respectively.
The primary VOCs found in the ground water at the AVCO
Lycoming Site include TCE, DCS and vinyl chloride. The shallow
ground water in the overburden on-site contains concentrations of
TCE up to 17,000 ppb and DCE up to 7,000 ppb. Vinyl chloride was
also detected in the shallow ground water on-site at concentrations'
of 520 ppb. The ground water in the bedrock on-site contains
concentrations of TCE up to 13,000 ppb and DCE up to 8,400 ppb.
The direction of ground-water flow at the AVCO Lycoming Site
is generally to the south toward Lycoming Creek and the WMWA well
field. Contaminated ground water has migrated from the AVCO
facility in the direction of the well field. The shallow ground
water in the overburden off-site contains concentrations of TCE at
2,900 ppb and DCE at 980 ppb. The ground water in the bedrock off-
site contains concentrations of TCE at 730 ppb and DCE at 170 ppb.
Currently, carcinogenic risks resulting from analysis of 6
exposure scenarios (i.e., treated water provided by the WMWA, on-
site soils, Lycoaing Creek surface water and sediment, and air
emissions from the air strippers on-site and off-site) are at or
below the acceptable level of 10'6. This level is equivalent to 1
extra chance in 1,000,000 of contracting cancer due to exposure to
site-related contaminants.
However, the on-site and off-site contaminated ground water
contributes future risks for potential ground-water users. The
following 5 scenarios describe conservative risks due to these
hypothetical exposures to site-related contaminants.
47
-------
The untreated ground water in the WMWA well field and the
ground water in the monitoring wells located on Third Street
present an excess human cancer risk presently estimated to range
from 3 to 8 x 10' . This risk is primarily due to TCE present at
a maximum concentration of 19,000 ppb in 1988 in a monitoring well
near Third Street. The range of values for this scenario is 0.2
ppb and 1,900 ppb with an average value of 317 ppb. This risk
evaluation represents a highly conservative estimate of human
health risk and means that individuals exposed to ground water in
this area have a maximum of 800 extra chances out of 1,000,000 of
contracting cancer. Due to the conservative nature of this
assessment, however, the actual health risks will probably be
lower.
The off-site overburden ground water in the Elm Park area
presents an excess human cancer risk presently estimated to range
from 3 to 6 x 10"A. The risk is primarily due to beryllium and TCE
present at maximum concentrations of 3.5 ppb and 860 ppb,
respectively. The range of values for beryllium is 0.4 ppb and
3.5 ppb, and for TCE, the range is 1.1 ppb and 860 ppb. The
evaluation represents a highly conservative estimate of human
health risk and means that individuals exposed to ground water in
this area have a maximum of 600 extra chances out of 1,000,000 of
contracting cancer. Due to the conservative nature of this
assessment, however, the actual health risks will probably be
lower.
The on-site overburden ground water presents an excess human
cancer risk presently estimated to range from 0.6 to 5 x 10"2. The
risk is primarily due to vinyl chloride present at a maximum
concentration of 1,100 ppb in 1988 in a sample from an on-site
monitoring well. The range of values for this scenario is 1 ppb
and 1,100 ppb with an average value of 126 ppb. This risk
evaluation represents a highly conservative estimate of human
health risk and means that individuals exposed to ground water in
this area have a maximum of 50,000 extra chances out of 1,000,000
of contracting cancer. Due to the conservative nature of this
assessment, however, the actual health risks will probably be
lower.
The off-site bedrock ground water presents an excess human
cancer risk presently estimated to range from 3 to 6 x 10' . The
risk is primarily due to TCE present at a maximum concentration of
1,200 ppb in a sample from a monitoring well located south of Third
Street. The range of values for this scenario is 0.5 ppb and 1,200
ppb with an average of 439 ppb. This risk evaluation represents
a highly conservative estimate of human health risk and means that
individuals exposed to ground water in this area have a maximum of
600 extra chances out of 1,000,000 of contracting cancer. Due to
the conservative nature of this assessment, however, the actual
health risks will probably be lover.
48
-------
The en-site bedrock ground water presents an excess hur.ar
cancer risk presently estimated to range from 0.3 to 2 x 10"2. Thl
risk is primarily due to vinyl chloride and TCE present at maximum
concentrations of 250 ppb and 19,000 ppb, respectively. The range
of values for vinyl chloride is 1.0 ppb and 250 ppb with an average
of 52 ppb. The range of values of TCE is 0.5 ppb and 19,000 ppb
with an average of 2,333 ppb. This risk evaluation represents" a
highly conservative estimate of human health risk and means that
individuals exposed to ground water in this area have a maximum of
20,000 extra chances cut of 1,000,000 of contracting cancer. Due
to the conservative nature of this assessment, however, the actual
health risks will probably be lower.
Toxicity Assessment
Cancer potency factors (CPFs) have been developed by EPA's
Carcinogenic Assessment Group for estimating excess lifetime cancer
risks associated with exposure to potentially carcinogenic
chemicals. CPFs, which are expressed in units of (mg/kg-day) -1,
are multiplied by the estimated intake of a potential carcinogen,
in mg/kg-day, to provide an upper-bound estimate of the excess
lifetime cancer risk associated with exposure at that intake level.
The 'term "upper bound" reflects the conservative estimate of the
risks calculated from the CPF. Use of this approach makes
underestimation of the actual cancer risk highly unlikely. Cance;
potency factors are derived from the results of human
epidemiological studies or chronic animal bioassay to which animal-
to-human extrapolation and uncertainty factors have been applied.
As described above, excess lifetime cancer risks are
determined by multiplying the intake level with the cancer potency
factor. The resulting risks are probabilities that are generally
expressed in scientific notation (e.g., 1 x 10"* or IE"6). An excess
lifetime cancer risk of IE'6 indicates that, as a plausible upper
bound, an individual has a one in one million chance of developing
cancer as a result of site-related exposure to a carcinogen over
a 70-year lifetime under the specific exposure conditions at a
site.
Reference doses (RfOs) have been developed by EPA for
indicating the potential for adverse health effects from exposure
to chemicals exhibiting noncarcinogenic effects. RfDs are exposure
levels for humans, including sensitive individuals, that are likely
to be without an appreciable risk of adverse health effects.
Estimated1,intakes of chemicals from environmental media (e.g., the
amount of a chemical ingested from contaminated drinking water) can
be compared to the RfD. RfDs are derived from human
epidemiological studies or animal studies to which uncertainty
factors have been applied (e.g., to account for the use of animal
data to predict effects on humans). These uncertainty factors hel'
49
-------
to ensure that the RfDs will not underestimate the potential
occurrence of adverse noncarcinogenic effects.
Potential concern for noncarcinogenic effects of a single
contaminant in a single medium is expressed as the hazard quotient
(HQ) (or the ratio of the estimated intake to the reference dose).
By adding the HQs for all contaminants within a medium or across
all media to which a given population may reasonably be exposed,
the Hazard Index (HI) can be generated. The HI provides a useful
reference point for gauging the potential significance of multiple
contaminant exposures within a single medium or across media.
A summary of quantitative toxicological information for the
considered compounds selected for the AVCO Lycoming Site are
presented in Table 8.
Risk Characterization
The potential carcinogenic risks associated with this site
were calculated by multiplying chronic daily intakes by the
appropriate carcinogenic potency factors. It is the policy of the
EPA to present a conservative estimate of site risk as represented
by reasonable maximum exposure (RME) scenarios, rather than by risk
ranges. This approach may be explained as the highest exposure
that is reasonably expected to occur at a site. It includes
consideration of both exposure parameters and exposure point
concentrations for their relevance as reasonable maximums. Despite
the conservative nature of the AVCO Lycoming Site risk assessment
(an approach that is in accordance with EPA policy), reevaluating
site risk according to specific EPA methodology would still result
in a value greater than 1 x 10"4 from the corresponding media.
Thus, both approaches conclude that similar media-specific
remediation is required.
In this respect, both reasonable and worst-case risks were
calculated using reasonable and worst-case chronic intakes rather
than presenting risk in terms of the RME. The resultant potential
risks are presented in Tables 9 through 17. The resulting
carcinogenic risk provided an estimation of the excess probability
of an individual developing an excess cancer over a lifetime as a
result of exposure to a particular compound or set of compounds
under the assumed conditions of the exposure. This estimate was
also sometimes referred to as the incremental or excess individual
cancer risk of 20 to 25 percent. Risk associated with exposure to
a set of .compounds was estimated by summing risks associated with
exposure to each compound.
Calculated ranges of lifetime carcinogenic risks for the
combined feasible scenarios are presented in Table 18.
50
-------
l.tl.lc 8
Summary ol Qu»nUUlWa ToilcoJoglcaJ Inlurmallon
Tailron lycominfl
WlUtamaporl, PannaylwanU
Campound
1.2 DkNofoatoyiarw (lolal)
IfkMMOatrytana
loluaoa
Vtnyt Chkxlda
Ba4uo{a)pyiana
Barium
Cadmium
Uanpanaia
BatyMuni
laad
lia*avalanl QuooOum
Oral RID'
{!******
240641
NA
400641
NA
NA
640642
600643—
640641
600643
144642
240642
')
Chronic
200642
NA
200641
NA
NA
740642
640644
100641
640643
140643
640643
Inhalation
(mp/kg/d
Sobchfonlc
NA
NA
200£,OO
NA
NA
NV
NA
NV
NA
NA
NA
RID*
*y)
Chronic
NA
NA
2006 »40
NA
NA
NV
NA
NV
NA
NA
NA
Oral SF"
(l/mtyfcg/day)
NA
1 IDE 02
NA
230E.OO
1 ISE.OI
NA
NA
NA
4304E.OO
NA
NA
InfuUtfon
NA
1 70E 02
NA
2 Bit 01
6 106,00
NA
NV
NA
NV
NA
NV
Cuclnoganlc
NO
U2
O
A
02
NC
Ul (1)
O
U2
U2
A|l»
Sourca
IMIU/III ASI
lit AS 1
II IIS
III ASI
SI'Hi M*
IHI'J
IlilS
IHIS
IHIS/lll ASI
Ilil'.WAlSltll
II IIS
and QuaiMM
IRIS • EPA'a orAna tntogiftlad RWi Intonnafcn 8y*kMn acoMaad Oc*o6w I WO
MtASI EPA a HaaMi ENacta A*aa*amart Summary Tatta* TWrd Quarts FY IM0(JUy
SPtCU Supartund Put*c Haa«h Ewaiuaion Manual. Odote* I»M
ATSOH Agancy It* loiio Sutalanoaa and Otaaaaa Ragfelry.
NA k>*uNUan< data to padonii o>MnMa»wa ftek a«aaaanMr«.
NC Nonc-Kiftogan.no «a«cfciogank:daiiJUdad>ntf»S
NV • M^aU*on nOtfatopa lactof riraflttrft. but rt(M iyfJL-**A* tinea t«M alamartt aia nol voUUI* and KjgU^a duU !• not a alto tpacttlc concha
(I) InhaUten patowy only; nol a ate apacttc concam.
allacU
•••Subchonfc: HID - Chronic RIO • 10
RIO Ralatanca doM
SF Sk>p*Wto<
Nola: QiaT&CVSF valuat ww a uMd hi fU« ctta
-------
Table 9
Aaaeeemenl el Carcinogenic Rltfc* • Scenario B
Monitoring Won* Located on Third Sueel
ToiUon Lycomlnfl
MNMlMMaod.
ROUTE OF
EXPOSURE
EXPOSED
COMPOUNDS
BCI
M»t4 1.2 DtchfcwoetVeno (total)
TrkttoraotiytoiM
CMUaga«-l2 1.2 OkM
TrkMomoeSyteM
i (total)
1 J
(tolaQ
77E03
I4AEOJ
OOOE.OO
967E03
246E03
OOOE.OO
40OEO3
SOCEO3
000£,00
Jj
wca
JOflMnlm]
Slope Factor
4
000£»00
33IEO2
7J7EO3
OOOE.OO
NC
1 70C02
NC
NC
1 70E02
NC
NC
1 70E02
NC
HCI • SF wca • SF
0 E.OO
3 £06
0 E.OO
0 E.OO
4 EO6
0 E.OO
0 E.OO
ft £46
0 EiOQ
Donne! Chlda0*24 U Dkfctaot*y*em (total)
ChiUaeȤ-l2 1.2 DKttOfOOtftytene (total)
Aduta 1.2
Ingouon
2 ME 06
4 ME 06
TikMoiaottyta
2S2EO6
364E06
• OOE06
IOIE05
44IE06
7 JOE 06
490E-O6
3»l£06
904E-06
NC
1 IOE 02
NC
NC
I lOt 02
NC
NC
1 IOE 02
NC
.OO
2
0 E.
3
0 E.OO
0 E.OO
GMdau»2« !.24*e«ofBOtVeoe (total)
T»ichtefoo*V»«ona
CMda0a6l2 I
Manjanaia
Adult*
likMoraoeSytoM
Uanpanaia
1.2 OkMoioottytano (totel)
.Mono****
• 77E 03
I48E03
279E02
• 67EO3
246E03
3 07E 02
400EO3
SOflEOJ
1.2 7 1 02
274EO6
326E-06
2.9IE05
300E02 NC
4 76£ 03 I IOE 02
3 I9E02 NC
33IE02 NC
787E03 I IOE 02
352EO2 NC
I37E02 NC
I 63E O2 I IOE 02
I 46€ 02 NC
faUHMMltonrWaifl
Eoa
E.OO
E.OO
L07
LiOO
0 E.
0
1 W
0 E.OO
2 £06
.00
E.OO
3 £06
0 E.OO
0 E.OO
6 E06
.0 E.IM
1 B44
08
NC • Noncafcmoojn
RCI • Reatonatote chtonic mlaha bated on aweo* conoantrauon
WCCI • Wotti «a«« chiomc otafc* baaadon maitoum coneenkaaon
00
0 E.OO
£06
£.00
E.OO
E O4
E.OO
0 E.OO
3 E
-------
l.llile 10
Uno0**Oc fttek*
Oft-Stt* OvwtturtMi MoAMoring ttMM
o
00
•2 -3-1
00
ROUTE Of
EXKMUAE
EXFOAEO
fOrULATtOM
COMPOUNDS
ACt
(Mft*»*«y)
WCQ
cuMi«»ft-ia i>i
<^li!kfcfc*^.44i»iifty»fcfi.it
300EO4
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
I&OE43
4»7E04
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
20ȣXW
I ME 00
I20EO4
544E04
CMUag»*l2 1.21
.(Ml)
I JSEOi
l«7EOa
LMd
442EO*
I24EO*
206E04
SMEOO
7 IOE 06
3 24E 04
3 IBE06
2 I6E03
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE.OO
OOOE^M
OOOE^X)
OOOE^O
JW^
I20E04
644E04
2UE06
4O8EO*
I«7EO«
442E06
I«7E06
I47EO6
7 IOE 06
324E04
3 I6EO6
NC
I 70E02
NV
NC
NC
NC
NC
I 70E02
NV
NC
NC
NC
NC
I TOE 02
NV
NC
NC
NC
NC
I IOE 02
430E.OO
NC
NC
NC
NC
I IOE 02
430E.OO
NC
NC
NC
NC
I IOE 02
430E.OO
NC
NC
NC
foW P~m*l ftttn
BCl'Sf
0 £.00
4 £06
0 E.OO
0 E.OO
0 E.OO
0 E.OO
0 E.OO
• to*
0 £.00
0 E.OO
£.00
£.00
0 £.00
2 £04
0 £.00
•O E.OO
0 £.00
0 E.OO
0
0
0
0
I
0 £.00
6 £0*
• £04
0 £.00
£.00
£.00
0 E.OO
• £0*
7 £0*
0 £.00
0 £.00
0 £.00
0 E.OO
2 £0«
3 £07
0 £.00
0 £.00
0 ( .<«>
WCCj^Sf
0 E.OO
4 EO4
0 E.OO
0 £.00
0 £.00
0 t .OO
0 E.OO
• £ 04
E.OO
E.OO
£.00
E.OO
£.00
I £04
0 E.OO
0 E.OO
0 E.OO
0 E.OO
4 £47
0 £.00
4 £0*
• £0«
0 E.OO
0 E.OO
0 E.OO
0 £.00
6 £ 0»
1 E0«
0 E.OO
0 E.OO
0 £.00
0 £.00
2 £ 07
3 t 01
0 £.00
0 £.00
0 J .00_
.._ —.
RUE CfxoMlc HUE • a
**f
4 23£ O4
• ME 0*
• 6M O4
I 4/E O6
1 Tttt 03
3 04E 04
• oat o/ »»3£oa
a »afc 01
06
i oiȣ oa
7 I6EOC
3t»3£ Oa
2S/EO/
4 46^07
-------
Table 10 (cnittM)
AMMJMMH! of Cwctoogmlc M»h« - Scwurio C
CMMIto O*«*u«tfMi Uonftoiteg MMte
T*itran LycMHtno
BCI
WGC4
• E-04
3 £44
00
30
>>
-------
T.I hi i- II
Hl»k» - Sc«rwirto
On-&ll« Ov*rt»urd«« Monitoring W*««
08
OD
PI
ROUTE OF
turoauflE
EXPOSED
JUIIttL
CQMPQUHM
RCI
WCC4
(k>uJ)
1.2
QMWa9»*l2 1.2 Dk**»o*t*tMW (toUQ
IrtcttanwAtytMM
\Any4Chfanto
1.2 OMA»«>ti»*»«»« (to*W)
DMM!
., . . • - - •<•« •« r :
- ' ..•-';!.'• ;_i. j . s. i . _ ..'i, . ;
CMd«o»4 12 1.2 DK**»D«««vi*n« (tout)
VWtyl CMamte
t.24)KMoM>«4hytan* (total)
TfkttOT***^
Otfarttfe
1.2
Iritt
NC
I IOC 02
230C.OO
NC
NC
I IOC 02
230C.OO
NC
I IOC 02
230C.OO
NC
£07
E 06
0 t .00
0 E.OO
2 £07
I E 06
£.00
E.oo
£07
£ 06
_fl Lital
t E-O*
E.OO
8 EOS
7 £04
0 E.OO
E.OO
2 E 04
I E 03
0 E.OO
0 E.OO
3 £04
2 £03
_fl L»WI
.LLM
NC
HC4
WCCI
Reasonable Carcinogenic Rlsh= 6 £03
Cas« Carcinogenic
5 £02
-------
Table 12
Aaiaaamanl ol Carcinogenic RUk» • Scenario E
CXI SIM Bedrock Monitoring Well*
TeiUon LycoMlng
WttUmtpofl. Pennsylvania
-o
08
OO
II
NC - NoncaidnogMt
RCI Rc.ison.ibto cruoruc Nil.tki! b.i:-i!d on a«;i Jijc cont^itnalKin
WCCl Wo4klca*u cntomc uttaku basutl on niawmum coitomUaiMxi
Reasonablo Carcinogenic Risk = 3
Worst-Case Carcinogenic Risk;
ROUTE OF EXPOSED
EXPOSURE POPUtAIIOM COUPOUMOS
lnnala>an CMMag§24 1.2 O«*»o«oe*Vene (total)
TntMonweSylena
VAoylChtonde
Barium
CfaUag*>«-l2 1.2 DKttoMM**iane (total)
Tnchkxoe4hytene
VtaytCMond*
Aduto t.24kftkMMlMMM> (total)
Ukwl ^jtinaArW
""" ' O*m*"' CtMktao»24 1.2 Dkitooe^tene (total) ' '
Vinyl CMomto
Ch«dag*6l2 1^4Nc»*Moe*vleM (total)
VtojCMandB
AduU 1.2 Oid*MM«vfa«M (total)
>»- * /**kiw— rf4W
vVM I4v0nai
" lng»»l»n"X''""CfU«a^a24 *l*2 DicMoioetftylanti (total) "
VtnylChtonde
Banum
Chad age 6 12 1.2 DtcManMlhytena (total)
Vinyl Chtoode
Banum
Adult* 1.2 Dchtoroetftytene (total)
Tncttoroetoytene
VkiylCMonde
RCI
6 IOEO3
1 IOE 03
75OE 06
OOOE.OO
*72E 03
182EO3
I24E06
OOOE.OO
27BE03
376E03
2S7E06
iilft.'^;pf-. ..;
A36E06
1 ISEOa
iaiE04
775E06
209C06
1 43E oa
I50E04
SS6E06
7SIE06
&!3COa
I.09E04
6 IOE 03
1 IOE 03
7SOE06
1 I8EOI
672EO3
ia2E 03
1 24E 06
1 30E 01
2 7BE 03
376E03
2S7E 06
&ME.02
WCCI
ma/lut/di)
22SE02
300E03
2SOE06
OOOE.OO
246E02
497EO3
4 MEO6
OOOC.OO
I03C02
I03CO2
8S7EO6
OOOCfOO
Ji^STW
346EOS
46IE06
384E09
636E04
266C06
57IE06
4 76EO9
526EO4
205C05
206EOS
1 7IE043
300E03
2SOE06
4 ME 01
24SEO2
4 07EO3
4 ME 06
4S7EOI
1 03E 02
I03E02
8S7E06
I89EOI
la.
Slope Factor
NC
I 70E02
20SEOI
NC
NC
1 70C02
29SEOI
NC
NC
1 70C02
295EOI
NC
»< tnbMttltaa ftM »
NC
1 IOC 02
230C»OO
NC
NC
1 IOC 02
230C^M
NC
NC
1 IOC 02
230E.OO
NC
r«H/Jr«»M/AMr<
NC
1 IOC O2
230E.OO
NC
NC
1 IOC 02
230E.OO
NC
NC
1 IOC 02
230E.OO
NC
ttlltxnMtm flfiim
HC| * SF
0 E.OO
2 EOS
2 £06
0 E.OO
0 £.00
3 EOS
4 £06
0 E.OO
0 E.OO
6 EOS
B £06
0 f ,00
0 E.OO
2 £08
3 £08
0 £.00
0 E.OO
2 E08
3 Eoa
0 E.OO
0 E.OO
8 EO8
1 £07
0 EiOD
9 f-97 ...
0 £.00
1 EOS
2 EOS
0 £.00
0 E.OO
2 £05
3 EOS
0 E.OO
0 E.OO
4 EOS
6 EOS
0 £.00
WoiiiCase
SI'SF
0 £.00
b £05
7 £ 07
0 £.00
0 £.00
a E os
1 £06
O E.OO
0 E.OO
2 E O4
3 £06
0 f.fOQ
) £44
0 E.OO
S £08
9 £09
0 E.OO
0 E.OO
6 E 08
i Eoa
0 E.OO
0 E.OO
2 £ O7
4 £08
0 E.OQ
4 £~07
0 E.OO
3 i OS
6 E 06
0 E.OO
0 £.00
5 EOS
1 £ OS
0 E.OO
0 I .00
1 £ 04
2 £ OS
0 E.OO
6 £04
-------
T.I Me II
AtM«am«nl ol Cafdnoganlc Al»ks - Scenario F
On SIU Bedrock Monitoring W*Jls
Tailron Eycomlng
WUUarnapoil. Pcnnayrvanta
08
ROUTE OF EXPOSED
tnhalatoon Chlda*«24
Chadag«ai2
Addis
• •' •:-VWiiiiiill^^r'^
Da «ri • *;F
NC
1 704:4)2
29iE 01
NC
1 70E 02
29SE 01
NC
1 70£ 02
29i£ 01
0 E.OO
1 t 04
4 E OS
0 t.OO
2 E 04
6 E OS
0 E.OO
4 E 04
1 E 04
.; . : : TntirimiiiiMtn mil t £~oi
1 44E O4
I09E-OS
2 (ME 07
1 I9£ 04
1 3S£ OS
2S2E 07
6 S3E OS
485£ 05
906E 07
935E 02
7 IOC 03
1 33E 04
1 03E 01
t I7E 02
2 I9f 04
427E02
243E 02
4S4E 04
936E 04
730E OS
960E 07
775E04
904E OS
1 I9E^)6
SS6E 04
32b£ 04
426E 06
..:-.'• 1
6 lOE 01
4 75£ 02
625E 04
672E 01
767E02
1 04E 03
2.76E-OI
1 &3EOI
2. ME 03
Tot
NC
1 106 02
230t«00
NC
1 lot 02
23O4.00
NC
1 I0£ 02
230C.OO
NC
1 tOt 02
230C.OO
NC
1 lOt 02
230t«00
NC
1 tOt 02
230E.OO
0 E.OO
1 E 07
S E 07
0 E.OO
1 E 07
6 E 07
0 £.00
S E 07
2 LQfi
A* 4 £40
0 E.OO
a E os
3 E 04
0 E.OO
1 E 04
S E04
0 E.OO
3 E 04
1 E 03
•/irtaiirton ft/iii i-t^u —
wrrt • SF
DLilil iJI
0 E.OO
6 .04
2 04
0 ,00
t 03
:i . 04
0 1 , 00
3 1 03
fi Lfli
6 £ -01
0 ,OO
tt ()/
2 O6
0 ,()O
1 06
3 06
0 ,00
4 06
1 LQi
t £45
0 .00
b 04
1 03
0 .00
9 O4
2 E 03
0 E.OO
2 E 03
5 1 03
1 £02
00
ii
NC
FtCI -IUa«onab*achionicinta»i«b4»^lonaw«i«o«conc«ntiatk>n *''»
chionic mta»* bu«d on roajiimum conconiiauon
Reasonable Carcinogenic Rlsk= 3 E 03
Worst-Case Carcinogenic Risk:
2 E 02
-------
Tabto 14
AtMMflMftl ol C«rcino0anic Rli«* • Scenario G
HeMvatml Chromium AIM In Ground Water
Taiuon Lycomlng
EXPOtEO
CtvoirrfumVI
ChromluniVI
RQ
wcci
Slop* Factor
HCI'Sf
OOOE.OO
OOOEtOO
OpO£.»qO
>-:'2:^iti
3.I0E-04
2A4E-04
208E-OI
2.29E-OI
OOOEiOO
0006*00
OOOEtOO
NC
NC
NC
0 E.OO
0 E»00
Q E.QQ
« e.
7.20E04
S.ME04
4.60E^)I
SITE 01
NC
NC
NC
NC
NC
0 E.OO
0 E.OO
Q EjQQ
999*^9 i,
0 E.OO
0 E.OO
Q E.(
fca^
NU -
RCI • AMMMM* ctoonte InU** iMMd on a
Caiclnoo«nlc Rlaka 0 E*00
Wor»l-CaM Carcinogenic
0 E.OO
0 E.OO
Q EtQQ
0 E.OO
0 E.OO
Q
,<
0 E.OO
0 E.OO
L±flQ_
0 E»00
"D
08
OQ
-------
Table IS
Assessment of Carcinogenic Risks lor Soils (0-6II. below pavement)
Texlron Lycomlng
WUUamspon, Pennsylvania
ROUTE OF
EXPOSURE
EXPOSED
ULAJJML
COMPOUNDS OF
CONCERN
RCI
wcci
(mgAg/dflv) (mo/ka/djvl
Slope Factor
(l/mo/ha/div)
HCI • SF
WCCI • SF
Inhalation
mo/m3
lagsM
Chid aoe 0-12
Adutts
Toluene
TrtcfOoroetiytefte
Toluene
Tftchloroetiytone
Toluene
630E02
121E04
471E02
135E04
144E02
B.78E 01
682E44
655£01
759E04
201EOI
NC
1.70E-02
NC
1.70E-02
NC
170602
0 E*00
2 E 06
0 E.OO
2 E 06
0 E«00
4 E06
NC - Noncardnogefl
RCI - noeionahte chrenlc Intahe based on average conoeniratton
WCCI - Worst-case chronic Intake based on maximum concentration
0 E«00
1 E 05
0 EiOO
1 E 05
0 E«00
2 £05
Reasonable Carcinogenic Rlsk= 8 E-O6
Worst-Case Carcinogenic Rlsk= 4 E-05
-a
08
OO
>>
-------
TabU 16
Assessment ol Carcinogenic Risks • Lycomlng Creek Surface Water
TsKlron Lycoming
Wllllemsporl, Pennsylvania
ROUTE OF
UPQSURE
Wialalion
mg/rn3
EXPOSED
POPUiannM
Chid age 24
Child age 6- 12
COMPOUNDS
1.2-Dichloroelhylene (total)
ThchkMoethylene
Manganese
U-DichkMoelhylene (total)
TrichkMoettytene
Manganese
1.2-OichkMoethyiene (total)
RQ
(ma/fco/da-vl
524E-08
9.46E-10
NV
WCCI
(tnft/io/div)
TftctUMoetfiyten*
. ., . ^
Dermal Chid age 6 12
Adufts
2.DE49
NV
120E-06
340E-09
NV
226E07
2.9IE09
NV
340C07
650£^9
NV
523E08
1.0SE-08
HY
Slope Factor
(1/mgVkg/day)
UJfehtoroethylene (total)
Trfchtofoetiylene
Manganese
UOicMoroathybna (total)
Trichloroertiytene
S6SE47
1S3£-0«
7J6E06
246E06
470E08
34IEOS
456E07
1.46E06
NC
I70E02
NC
NC
1 70E02
NC
NC
I70E02
NC
MM *
NC
1 10602
NC
NC
I.IOE02
HCI' SF
0 £,00
2 Ell
0 E»00
0 E*00
4 til
0 E.OO
0 E«00
6 E It
0 EtOO
. 1 &10
0 E»00
2 E 10
0 E«00
0 EtOO
5 Ell
"i^eHiofl" " Chad age 6 12
TricMoioalhytMM
ManganaMi
UOicMoio^hyisna (total)
4.07E4M
1 HE^S
190E05
363E07
263E04
393E06
I.25E07
545E05
NC
IOE02
NC
NC
.IOE02
NC
0 EtOO
I E 09
0 EtOO
0 EtOO
4 E 10
0 £iOQ
WCCI • SF
0 EtOO
5 Ell
0 EtOO
0 EtOO
1 E 10
0 EtOO
0 EtOO
2 E 10
0 EiOO
9 £10
0 EtOO
5 E 10
0 EtOO
0 EtOO
2 E 10
_fl_£iOO_
7 £^ia
0 EtOO
4 E 09
0 EtOO
0 EtOO
I E 09
0 EiOO
O
_
^^^^ *^^*^
oo
NC - Noncarcinogan
NV - Not voiatte
RCI - Raasonabla chronic inlaka basad on avataga concanliaikm
WCCI - Wofkl-casa chronic inlaka basad on maximum concanti alion
Reasonable Carcinogenic Rlsk= 2 E-09
Worst-Case Carcinogenic Rlsk= 6 E-09
-------
Table | 7
A»Mstm«nl ol Carcinogenic Risks - Lycomlny CiMk
Tcilron Lycomlng
Wllllamtport,
ROUTE OF
EXPOSED
>QPtJLAHQ
Ch*Jag*ft-l2
Adult
Bwyftum
RCI
lAtfd
663E 06
I 06t 08
76«E 09
I Obt 06
260£ 09
202E 09
WCCI
89lt 06
I 6/t Ofl
I S2L 0«
I 411 06
440L 09
40OC 09
Slop*
NC
430t.OO
I Ibt.OI
N<;
4 JOt.OO
»U .01
NC - Noncaicinogan
ItCI • R««tonat*U ctuonk: inltk* b««4Ml on aw«iag« canocnbalion
WCCI Woi»l<«M ctMomc miak* b*MMt on mMiamm oono»nli«Uon
HCILJ
0 t.OO
s t. oa
9 I 00
0 t ,00
i I. ua
_.2.L.Utt.
1 £01
0 I. ,00
/ t. Ott
:• » o/
0 I ,01)
'I I OU
Reasonable Carcinogenic Risk- 2 E 07
Worst-Case Carclnogonic Risk
3 t 07
O
00
-------
f-J
08
oo
fi
Table 11>
Summary of Lifetime Carcinogenic Risk
Tailron Lycomlng
WllUamsporl. Pennsylvania
GROUND WATER
Treated WMWA Production Wei teld Scenario A
Third Sveet Monitoring WeeV - Scenario B
Oil Ska Overburden - Scenario C (Elm Park Area)
On Sfce Overburden • Scenario 0 (Plan! Southern Boundary)
ON-Sto Bedrock-Scenario E
On-Sfte Bedrock-Scenario F
Heiavalent Chromium Area • Scenario O
ON-SITE SOILS
LVCOMtNO CREEK SURFACE WATER
LVOOMUM CREEK SEDIMENT
EXPOSURE FROM AIR STRIPPERS
TOTAL FEASIBLE EXPOSURES
(Scenario A. sols, surface water, air. sediments only)
Scenario
Typ.
RaaaonabUfl)
Carcinogenic
Rl*k
Wor*l Ca»a (2)
Carcinogenic
Hl*k
Faasltoi*
0"
0"
•E44 |B2J
HypotfMtcal
HypotfwttcaJ
•E-04 [A « BJJ
;!. ..-.., '-. • '.
Feasible
Feasible
0"
SE 08 (B2|
2£ 00 (B2|
o"
4E OS (B2|
6E Ofl (B2|
2E 07 (A. Bl. B2| 3E^)7 (A. Bl. B2|
lE^flf IE 05ft
9E-06 SE05
Note: USEPA guWeUnea kv evaluaJton of caidnogenk: riak apedly a laigei range of acceptable ritfc between lE^ and IE 4.
Shaded value* btolcale ••dmaled polanlaJ risk* whkii exceed ihU guideline.
• And Infiuenldau Horn WMWAwei laid.
* * Risk to negHglbie. and therefore rapraaenied as iero.
(I) Based on average concanlraton of compounds In medium.
(2) Based on maximum concenliation ol compounds In medium.
A • Class A (known human) carcinogen
B2 • Class B2 (probabla human) carcinogen
t Based on reasonable case scenario lot Group 1 (population pietlicitxt in au modeling wheie the maximum r.oncunit aitoo
should occur).
t f Based on worst-case scenario lor Group I (populanon ptetiicted in an modeling wheia iha maiimum
should occur).
-------
Ncncarcir.cgenic Risk
The nor.carci-ccer.ic hazard index is the ratio of the excected
potential dose to acceptable exposure levels. Values of less than
unity .'i.o) indicate that no hazard exists. The r.oncarcincgenic
hazard indices were obtained by dividing the chronic daily intakes
by the appropriate reference doses. Tvo hazard indices were
calculated for the AVCO Lyccming Site:
reasonable chronic hazard index (reasonable chronic
intake/reference dose), and
worst-case chronic hazard index (worst-case chronic
intake/reference dose).
The noncarcinogenic hazard indices including the total
lifetime hazard associated with simultaneous exposure under
multiple feasible scenario is summarized in Table 19.
Environmental Risk Assessment
The environmental assessment represents a characterization of
risks completed by identifying potential exposures to ecological
receptors and estimating possible effects associated with such
exposures. The principal ecosystem of the AVCO Lycoming Site and
surrounding environment was divided . into three components:
terrestrial, aquatic and wetlands. There are no historical or
archeological sites within the area surrounding the AVCO Lycoming
Site.
Terrestrial Community
The AVCO Lycoming Site property and surrounding study area is
in Williamsport, an urban area of Lycoming County, Pennsylvania.
Most of the plant property is developed with buildings, paved
surfaces, roads and parking lots. The small, remaining open areas
consist of maintained lawns consisting of small grass strips around
a few buildings. Th« laclc of an established plant community, the
day-to-day industrial activities, and the chain-link fence
surrounding th« majority of the property impede wildlife from using
the limited cita resources.
The area surrounding the facility is characteristic of urban
commercial and residential properties. Much is developed by
buildings,' parking lots, roads, and houses. Vegetation within this
urban area is limited to noncontiguous ornamental trees and shrubs.
The residential and commercial area would appear to provide limited
habitat suitable for various song birds and small mammals such as
mice, squirrels, chipmunks, rabbits, and groundhogs. No endangerej
63
-------
POOR QUALITY
ORIGINAL
Tabla 19
Summary at UfXIm* Kioncarcinog«njc Hazard lndlc«*
T«itron Lyeomlng
Wllllamaport, Pannayrvania
Scanano R*ason«oi«'(i) Wont-Ota'(2)
Typa Chronic Hazard Chronic Hazard
GROUND WATER
I
'•eatee WMWA WtH fl«d - Scanano A
| "hira STBWI Monitoring Wads'" • Scaoano 3
i
0"
0"
OCf
TE-Of
3E-01
:«-S:a Cvarouroan • Scanano C (Em Park Ana)
Hypotf»oc»J
OCf
darru/n
On-Siv Ov*rourowfl • Scanasio 0
.P'ant Souinam 3oo"0*ry)
Lttti
OCf
*¥•«*
fltMT
Crt-Sits Badrock • Scanano E
On-Sita Badrodt • Scanano F
Haxavalant Chromium Ana • Scanano G
ON-SITE SOILS
LYCOMING CREEK SURFACE WATER
LYCOMING CREEK SEDIMENT
EXPOSURE TO AIM STWP»tft»
TOTAL PEASUlf OFO6UIV
(Sccnano A, idto. Mtea w»ar. air,
CCf
96-03
1E-03
SE-03
iE-oat
7E-02
9E-01
3E-03
7E-03
56-03TT
9€-01
only)
Noe»: EPA quBjaino lor r^amien ol nonoitinoganic ^xard jnde» apaofy « vHu« o< 1
.ojicaa ftiidi «ie**d 1 irxfcui txct flw« ia fw poMntt tar •dxafu hsalft
txpoat^ oondien*. Huard indon grMitr 9tn 1 m
•in eases wtwra etuorae hazard it gnmm tfian on*, tw hazard
Th«*t groupino* ara pravidad oVaedy baiew tf» total hazard
••Hazards rapratantad «• zare tinea eompeunda vara not
WMWA at fw v*l flaid.
witi »• drfrwd
on targat organ*.
in tfia •ffluant ground waaw tamptoa
anafy«eal r»aUt» for WMWA wal IMd Mluant ground waaw aamptoa,
OCE • i.2-0icfaoroa»y)ana (Btafl
{ i ) - Basad on avaraga cancan rattan o( eompounda in a madkjm
(2) • Basad on mawnurn conoantraton of comooundt in a madun
snould occur).
Basad on worsj-caaa scanano for Gnxaj 1 (popUaton
ar modalnQ whara *>a ma»murti conBadWSort
n ar medasng whara tha maonum conesnnaon
-------
species have beer, identified within the area surrounding the AVCD
Lyccaing Site.
Aquatic Ccar:ur.ity
Lycoaing Creek, the closest watervay to the site, is
approximately 1,500 feet east and southwest of the site. Much of
the natural ecology of the Lycoming Creek study area has been
repeatedly altered in the past by logging activities, levee and
flood wail construction, and road construction. within the study
area, six autcncbiie bridges and two railroad bridges span Lycor.ir.g
Creek. The natural flocdplain of Lycoaing Creek has been changed
by a flood protection levee systea along the east and west shores.
The levee systea was built by the U.S. Aray Corps of Engineers'
3altiaore District in 1955.
Today, the ecology along Lycoming Creek is fairly stable with
the only streaa and floodplain alterations occurring froa naturally
high waters due to spring thaws or heavy rains. Aquatic habitat
in the study area of Lycoaing Creek is coaposed of riffle and pool
areas. The substrate of the stream is predominantly coaposed of
equal amounts of boulders and rubble with the interstitial spaces
filled with sand and gravel. Soae small-, narrow strips of emergent
vegetation also exist along the edges of the stream.
Pennsylvania Department of Environmental Resources (PADER;
classifies streams in Chapter 93 of their rules and regulations.
Sections 93.3 and 93.4 define protected and statewide uses of
streams. From the confluence of Long Run (north of the village of
Cogan Station, 5.5 miles upstream of Williamsport) to the Lycoming
Creek mouth at the West Branch Susquehanna River, Lycoming Creek
is classified by Chapter 93 as a warm water fishery. Upstream of
Long Run, the stream is classified as a cold water fishery. The
Pennsylvania Fish Commission stocks Lycoming Creek with trout from
Cogan Station upstream to tha Lycoming County line.
As part of tha RI, qualitative kick-net and semi-quantitative
aultiplate macroinvertebrate samples were collected from five
stations along Lycoming Creek. Conclusions from the qualitative
sampling results indicate good water and sediment quality at four
of the five stations based on the diverse, healthy,
aacroinvertebrate communities observed at these stations. The
lower diversity and numbers observed at one of the stations may
have been due to the generally poor physical habitat available for
colonizatipn and/or high stormwater surges from the storm sewer
which scout the substrate and cause unstable habitat conditions.
Conclusions from the semi-quantitative multiplate sampling results
indicate good water quality based on the diverse, healthy
macroinvertebrate communities at all stations.
65
-------
Wetland Community
A field investigation of the study area identified several
wetland areas along the banks of Lycoming Creek. These areas are
confined to the loo-year floodplain within the flood protection
levee system that parallels the east and west shores of Lycoming
Creek. Wetland systems along the stream's shores include
palustrine emergent, scrub/shrub, and forested wetlands. Emergent
and scrub/shrub wetlands exist along most of Lycoming Creek's
banks. The forested wetland areas exist near the mouth of Lycoming
Creek and along the north bank of the West Branch Susquehanna
River. Both Lycoming Creek and the West Branch Susquehanna River
are classified by the National Wetland Inventory Map as riverine
wetland systems.
Identification of Potential Receptors
The potential receptors for possible site-related impacts to
the surrounding ecosystems are populations of aquatic and
terrestrial organisms inhabiting Lycoming Creek and the forested
and shrub wetlands along Lycoming Creek. The potential receptor
populations are characterized below in terms of terrestrial and
aquatic organisms.
wildlife populations along the stream appear to be healthy
for an urban area. Wildlife and signs of wildlife observed within
the forested and shrub areas along Lycoming Creek included
groundhog, rabbit, raccoon, gray squirrel, garter snake, and
various species of birds.
The Lycoming Creek supports a diverse population of warm and
cold water fish. Fish species that are known to occur in the Lower
West Branch of the Susquehanna River are listed in the RA for this
site. Many of these species would also occur within Lycoming
Creek. Game fish most likely to inhabit Lycoming Creek include
small mouth bass, rock bass, bluegill, brown and yellow bullhead,
yellow perch, chain pickerel, and brown trout. Other wildlife
species that may inhabit Lycoming Creek include several species of
snakes, turtles, and amphibians.
Exposure Assessment
Exposure assessment is the process of measuring or estimating
the intensity, frequency, and duration of exposures to a compound.
The purpose of this assessment is to determine the potential for
exposure to site-related compounds by potential receptor
populations inhabiting Lycoming Creek and the surrounding study
area. Chemical analysis of the surface water and sediments, as
well as the collection of macroinvertebrates from Lycoming Creek
during the remedial investigation was the basis for the exposure
66
-------
assessment:. These data provide a direct assessment of the stream's
physical and biological features.
Very few VOCs were detected in the sediment samples. TCE was
detected in SD-4 at a trace concentration of a ppb and in SD-3 at
a quantitatively estimated concentration of 1 ppb. Chloroform and
toluene were also detected at quantitatively estimated
concentrations in SD-3. Mo pesticides or PCBs were detected in any
sediment samples.
A number of semi-VCCs, all polyaromatic hydrocarbons (PAKs),
were detected in the sediments at Stations 2 and 3. Eight PAHs
were quantitatively detected at Station 3 and only two were
detected at Station 2. PAHs are formed during incomplete
combustion of organic matter in industrial furnaces, residential
heating units, motor vehicles, and fires, and are found primarily
in particulates in air, soil, and sediments. These compounds are
also typically associated with asphalt/tar based materials. The
presence of these compounds in the sediments at Stations 2 and 3
are not believed to be related to the site since most of these
compounds have not been detected in either groundwater or soil
samples collected from the facility. The Oliver Street storm sewer
travels 2,300 feet through Williamsport prior to discharging into
Lycoming Creek immediately upstream from Station 3. The
concentrations detected in the sediments at Station 3 are most
likely caused by stormwater runoff from the western portion of
Williamsport.
Risk Characterization «
The risk characterization integrates information from the
ecological characterization, exposure assessment, and toxicity
evaluation to produce an estimate of risk. The surface water
results shoved no exposure of any site-related compounds. Good
water quality is also indicated by the semiquantitative Hester-
Dendy results. The macroinvertebrate communities which colonized
the multiplate samplers at all stations were diverse and consisted
of sensitive species such as stoneflies, caddisflies, and mayflies.
The sediment data indicated the presence of a number of PAHs
at Station 3 and a few at Station 2. all of these concentrations
were below the available sediment criteria for the protection of
aquatic life. In addition, the source of the PAHs is most likely
the result of the stormwater runoff from the roads within the
western section of Williamsport and not a result of the Textron
Lycoming facility. The inorganic analyses of the sediment
indicated the presence of inorganics in the sediments at all
stations. Most inorganics are naturally occurring and their
concentrations are influenced by a watershed's geology, soils, and
industrial discharges. Six of the 12 inorganics detected
(aluminum, barium, cobalt, iron, magnesium, and nickel) were
67
-------
present at higher concentrations at the background Station 5 than
the other downstream stations. The remainder of the inorganics
detected were below the average Apparent Effect Threshold
Concentration. Cadmium and lead were also well below the
individual biota indicator's Apparent Effect Threshold
Concentrations. The criteria proposed by the New York State
Department of Environmental Conservation (NYSDEC) were exceeded
for cadmium, chromium, lead, iron, and nickel, however one of these
concentrations was above the NYSDEC Limit of Tolerance values.
Chromium, iron, and lead were also below the NYSDEC background
concentration. Chromium, a site-related compound is also at the
average concentration found in eastern U.S. soils. Therefore, it
is possible that the elevated level of chromium in the sediment
from Station 3 may be the result of soil erosion and discharge to
Lycoming Creek from the Oliver Street storm sewer outfall.
Considering the above, it is unlikely that exposure to sediment-
related compounds is significant. The sediment quality does not
appear to be impacting the macroinvertebrate community or the
aquatic system at any of the stations.
Conclusion of Summary of Site Risks
Actual or threatened releases of hazardous substances from
the Site, if not addressed by implementing the response action
selected in this ROD, may present an imminent and substantial
endangerment to public health, welfare, or the environment. The
Risk Assessment did not identify any threats due to exposure to the
air or direct contact. The only media of concern at the AVCO
Lycoming Site is through exposure to contaminated ground water.
Description of Alternatives
The Superfund statute and regulations require that the
alternative chosen to clean up a hazardous waste site meet several
criteria. The alternative must protect human health and the
environment, meet the requirements of environmental regulations,
and be cost effective. Permanent solutions to contamination
problems should be developed wherever possible. The solutions
should reduce the volume, toxicity, or mobility of the
contaminant*. Emphasis is also placed on treating the waters at
the site, whenever this is possible, and on applying innovative
technologies to clean up the contaminants.
In accordance with 40 C.F.R. §300.430 a list of remedial
response actions and representative technologies were identified
and screened to meet the remedial action objectives at this site.
The FS studied a variety of technologies to see if they were
applicable for addressing the contamination at the Site. The
technologies determined to be most applicable to these materials
were developed into remedial alternatives. In addition, the EPA
68
-------
has added the Mo Action Alternative (Alternative i) as required by
the National Contingency Plan (NC?). These alternatives ar^
presented and discussed below. All costs and implementation tiai
frames provided for the alternatives below are estimates.
Ccmr.on Elener.ts: All of the alternatives being considered would
include common components. Each alternative except the "no action"
alternative would include the continued operation of the existing
ground-water recovery wells and continued ground-water monitoring
to measure concentrations of site related constituents. EPA would
review the Site every five years to ensure continued protection to
human health and the environment for each of the alternatives,
including the "no action" alternative. Alternatives GW-3, GW-4,
and GW-5 include additional on-site ground-water recovery and
treatment. Also, institutional controls have been added to
alternatives GW-3, GW-4, and GW-5.
Alternative 1: Mo Action
Capital Cost: $ - 0 -
Annual O&M Cost: $ - '0 -
Present Worth: $ - 0 -
Months to Implement: - 0 -
The NCP requires that a "no action" alternative be evaluated
as a baseline for comparison to other alternatives. Under thi
alternative, no remedial action would be talcen at the site. The
existing ground-water extraction and treatment systems would not
be operated, however, ground-water monitoring would continue.
There are no ARARs associated with this alternative. Alternative
1 would not comply with the CERCLA preferences for a remedy that
employs treatment to reduce toxicity, mobility or volume as a
principal threat.
At the AVCO Lycoming Site, remedial actions have already been
undertaken, pursuant to a COA with PADER. Thus, a true Hno action"
alternative is not possible. The best approximation of a "no
action" alternative is ceasing current actions, that is shutting
off the on-site and off-site ground-water extraction system. The
no-action alternative would include ground-water monitoring
consisting of sampling and analysis in accordance with the existing
PADER COA.
Alternative GW-1; No Further Action
Capital Cost: $ - 0 -
Annual O&M Cost $ 10,100
Present Worth: $160,000
Months to Implement: - 0 -
69
-------
Under this alternative, EPA would take no further action
beyond the continued operation of existing ground-water recovery
and treatment on-site and off-site to prevent exposure to the
contaminated media or to reduce risk at the site.
Alternative GW-2; Institutional Controls
Capital Cost: $ 48,000
Annual O&M Cost: $ 11,300
Present Worth: $220,000
Months to Implement: 6-9
This alternative consists of institutional controls including
deed, zoning, and/or ownership restrictions to limit future
property use to those activities compatible with site conditions.
This alternative would also involve the construction and
maintenance of a fence around the western portion of the site to
prevent unauthorized entrance in this area.
There are no ARARs associated with this alternative, and it
would not comply with the CERCLA preferences for a remedy that
employs treatment to reduce toxicity, mobility or volume as a
principal threat.
Alternative GW-3; Ground-water recovery, chemical treatment
for metals, air stripping, emissions
controls, discharge of treated water
Capital Cost: $2,500,000
Annual O&M Cost: $ 442,900
Present Worth: $9,300,000
Months to Implement: 18-21
This alternative consists of a ground-water recovery system
to contain and collect contaminated ground water on-site.
Approximately 33 recovery wells would be installed around the
downgradient perimeter of the site to prevent any further off-site
migration of contaminants. The recovered ground water would be
pumped at 66 gallons per minute (gpm) froa the western site area
and piped to a dedicated on-site treatment facility and treated to
reduce chromium and subsequently precipitate it and other metals.
This ground-water stream would then be combined with the remainder
of the recovered ground water being pumped at 177 gpm from the
eastern and central portion of the site. The entire recovered
ground-water stream would then be pumped to an air stripper for VOC
removal. The off-gas from the air stripper would be treated by the
best available technology which includes carbon treatment or fume
incineration. The treated ground water would be discharged to
Lycoming Creek. In addition, institutional controls have been
70
-------
added to this alternative in the fora of limiting future property
use to those activities compatible with site conditions prevent any
potential for direct contact with contaminated soils.
The metals treatment facility would consist of the following:
a modular chromium reduction and chemical precipitation
system (coagulation, flocculation, and settling) for
metals precipitation, and
use of the existing en-site WWTP for solids dewatering
via a piate-and-frame filter.
An iron coprecipitation system would be used for chromium
reduction and dissolved metals removal, using ferrous sulfate and
polymer, at a pH of 9. It is assumed that the sulfuric acid and
caustic (used for pH adjustment) , and ferrous sulfate will be
stored and fed from the indoor tanks for the existing system.
Sludge will be recirculated through the process to improve
metals removal. The sludge will be dewatered and is estimated to
contain 30 percent solids after dewatering. The sludge will then
be transported off-site to an approved hazardous waste disposal
facility.
The air stripping system would include feed pumps, a blower
(1,300 cfm), and a packed tower 4 feet in diameter with a 20-foot
packed depth and an air-to-water ratio of 40:1. Effluent from the"
air strippers would be discharged to the Oliver Street storm sewer
and thereafter to Lycoming Creek. Effluent limitations would be
determined in coordination with PADER during the remedial design
phase. PADER limitations will likely require VOC removal, chromium
reduction, and metals removal. This overall treatment system would
operate until the ground-water cleanup ARARs were achieved or as
long as technically practicable.
The major ARARs associated with this alternative include the
Safe Drinking Water Act, the Clean Air Act and the PADER ARAR for
ground water for hazardous substances.
Alternative GW-4; Ground-water recovery, chemical treatment
for metals, chemical oxidation, discharge
of treated water
'Capital Cost: $ 2,400,000
'Annual O&M Cost: $ 526,000
Present Worth: $10,000,000
Months to Implement: 13-21
This alternative is equivalent to Alternative GW-3, except
for the use of chemical oxidation for organics removal, instead o
71
-------
air stripping. As in Alternative GW-3, the sludge generated from
the metals' removal process will be transported off-site to an
approved hazardous waste disposal facility. The chemical oxidation
process is most likely to include hydrogen peroxide addition to the
combined ground-water flow to oxidize organics. Catalysis of this
process would use ultraviolet light to hasten the oxidation
reaction and to carry the reaction to completion to carbon dioxide,
hydrochloric acid, and water. Prefiltration will be needed for
gross suspended solids and iron removal before chemical oxidation
for that portion of flow not treated via chemical precipitation.
In addition, institutional controls have been added to this
alternative in the form of limiting future property use to those
activities compatible with site conditions.
The oxidation unit proposed would be sized for 243 gpm. The
effluent from the unit would be discharged as described in
Alternative GW-3 above.
The major ARARs associated with this alternative include the
Safe Drinking Water Act, the Clean Air Act and the PADER ARAR for
ground water for hazardous substances.
Alternative GW-5: Ground-water recovery, chemical treatment
for metals. air stripping, emissions
controls, reiniection and discharge of
treated water, and in situ biological
treatment
Capital Cost: $ 3,300,000
Annual O&M Cst: $ 650,500
Present Worth: $13,000,000
Months to Implement: 18-21
This alternative would consist of the components of
Alternative GW-3 plus in situ biological treatment for ground water
beneath the Site. The recovery well system for this alternative
would be the same as that described in Alternative GW-3, but the
discharge scheme would differ due to the need for upgradient
reinjection of ground water to facilitate in situ bioremediation.
The ground water from the western portion of the site would be
treated for metals, and the entire recovered stream would be
treated for organics, as in Alternative GW-3. Also, the sludge
generated from the metals' removal process will be transported off-
site to an approved hazardous waste disposal facility.
The fair stripper used in this alternative has been sized to
meet the more stringent water quality criteria for reinjection.
The air stripping system would have a packed tower 4 feet in
diameter with a 30-foot packed depth and an air-to-water ratio of
80:1. The off-gas from the air stripper would be treated by the
best available technology which would include carbon treatment or
72
-------
fume incineration. An estimated 195 gpm of the treated ground
water would be discharged as described in Alternative GW-3 above
and the remaining 43 gpm would be reinjected. The water to L
reinjected would be treated in an upflow filtration unit to remove
suspended solids and metals and would then be dosed with an
oxidizing agent such as hydrogen peroxide (at an estimated
concentration of 500 ppm) and nutrients (nitrogen and phosphorus)
before discharge to the injection wells. Eight reinjection wells,
each recharging at 6 gpm for a total of approximately 48 gpm being
reinjected, are proposed for this alternative. The locations of
these wells will be based on the need to distribute nutrients
evenly within the overburden VOC plume to enable the bacteria to
efficiently degrade the VOCs. In addition, institutional controls
have been added to this alternative in the form of limiting future
property use to those activities compatible with site conditions.
The major ARARs associated with this alternative include the
Safe Drinking Water Act, the Clean Air Act and the PADER ARAR for
ground water for hazardous substances.
Sununarv of Comparative Analysis of Alternatives
A detailed analysis was performed on the six alternatives
using the nine evaluation criteria specified in the NCP 40 C.F.R.
§300.430(e)(a) in order to select a final remedy for Operable Uni^
(OU-l) . The following is a summary of the comparison of ear
alternative's strengths and weaknesses with respect to the nin
evaluation criteria. These nine evaluation criteria, which are
listed in Exhibit A, can be categorized into 3 groups; threshold
criteria, primary balancing criteria, and modifying criteria.
THRESHOLD CRITERIA
- Overall protection of human health and the environment
- Compliance with applicable or relevant and appropriate
requirements (ARARs)
PRIMARY BALANCING CRITERIA
- Long-term effectiveness
- Reduction of toxicity, mobility, or volume through treatment
- Short-term effectiveness
- Implementability
- Cost
i
MODITYING CRITERIA
- Community acceptance
- State acceptance
73
-------
EXHIBIT A. DMCRIPTIOM OF IVMOATIOM CXITIHIA
addresses whether or not a remedy will: cleanup a site to within
the risfc rang*; result in any unacceptable impacts; control the
inherent hazard (e.g., toxicity and mobility) associated with a
sits; and minimize the short-term impacts associated with
cleaning up -the site.
Compliance with AJAR 'a - addresses whether or not a remedy will
meet all the applicable or relevant and appropriate requirements
of other environmental statues and/or provide grounds for
invoicing a waiver.
Long-term Effectiveness and Permanence - refers to the ability of
a remedy to maintain reliable protection of human health and the
environment over time, once cleanup goals have been met.
Reduction of Toxicity. Mobility, or V«?i^** through Treatment -
refers to the anticipated performance of the treatment
technologies that may be employed in a remedy.
Short-term Effectiveness - refers to the period of time needed
to achieve protection, and any adverse impacts on human health
and the environment that may be posed during the construction and
implementation period until cleanup goals are achieved.
Impleaentability - describes the technical and administrative
feasibility of a remedy, including the availability of materials
and services] needed to implement the chosen solution.
Cost - includes the capital for materials, equipment, etc. and
the operation and maintenance cost.
Support Agency Acceptance - indicates whether, based on its
review of the RX,PS and £he Proposed Plan, the State concurs
with, opposes, or has no comment on the preferred alternative.
Acceptance - will b« assessed in the Record of Decision
following a review of the public comments received on the RI, FS,
and the Proposed Plan.
POOR QUALITY
ORIGINAL
74
-------
These evaluation criteria relate directly to requirements in
Section 121 of CZHCLA, 42 U.S.C. Section 9621, which determines
the overall feasibility and acceptability of the remedy. Thresho'
criteria must be satisfied in order for a remedy to be eligible fo
selection. Primary balancing criteria are used to weight major
trade-offs between remedies. State and community acceptance are
r.cdifying criteria that are formally taken into account after
public corrjr.er.t is received on the Proposed Plan. The evaluations
are as follows.
Overall Protection of Human Health and the Environment
Due to contaminant migration and contaminant concentrations
that exceed health-based levels, Alternative 1 would not be
protective of human health or the environment. Since protection
of human health and the environment is a threshold criteria for
any Superfund action, this alternative will not be selected and
thus need not be evaluated further.
Alternatives GW-i and GW-2 would continue to recover and treat
the contaminated ground water utilizing the existing recovery and
treatment system. These alternatives would provide limited
protection. Alternatives GW-3, GW-4, and GW-5 minimize off-site
migration of contaminants in ground water flowing beneath the
plant. These alternatives would provide adequate protection by
controlling and reducing risk through a combination of containment-
treatment and institutional controls. Alternative GW-3 wou..
contain and treat the contaminated ground water on-site while the
off-site contaminant plume is recovered and treated through the
existing ground-water treatment system. The effluent limits for
the discharge or treated ground water would be met for alternatives
GW-3, GW-4, and GW-5.
Compliance with ARARs
CERCLA requires that remedial actions meet applicable or
relevant and appropriate requirements (ARARs) of other federal and
state environmental laws, or that there are grounds for invoking
a waiver. These laws may include, but are not limited to: the
Toxic Substances Control Act, the Clean Water Act, the Safe
Drinking Water Act, and the Resource Conservation and Recovery Act.
A "legally applicable" requirement is one which would legally
apply to the response action if that action were not taken pursuant
to Sections 104, 106, or 122 of CERCLA. A "relevant and
appropriate" requirement is one that, while not "applicable", is
designed to apply to problems sufficiently similar that their
application is appropriate.
75
-------
All the alternatives, except for the "no.action" alternative
(Alternative 1), will meet their respective ARARs as referenced in
the FS. These include compliance with the Clean Air Act and PADER
Air Quality Standards for emissions from the Site. All discharges
of treated ground water to Lycoming Creek from Alternatives GW-l
through GW-5 should meet National Pollution Discharge Elimination
System (NPDES) requirements developed pursuant to the Clean Water
Act and PADER Bureau of Water Quality Management Standards.
The goal of the ground-water remediation is to achieve
background ground-water quality as required by PADER. Alternatives
GW-l and GW-2 would probably not achieve the Pennsylvania ARAR for
ground water in a reasonable time period.
Short-term Effectiveness
Alternatives GW-l and GW-2 consist of pumping and treating
ground water. These alternatives would utilize the existing
ground-water recovery and treatment system. The remediation time
frame associated with these alternatives is difficult to determine
but is expected to exceed that required for Alternatives GW-3, GW-
4 and GW-5 since no additional recovery wells would be constructed.
Short-term risks would be associated with the construction of the
ground-water treatment facilities and the installation of
additional ground-water recovery wells for Alternatives GW-3, GW-
4, and GW-5. These risks include potential exposure to VOC
releases during well installation and worker injury during the
construction of the associated ground-water treatment system. The
risks could be minimized by the use of personnel protective gear
by these workers. Also, the community will be protected from
potential VOC releases by continuous air monitoring during the well
installation.
Long-Term Effectiveness
For each of the alternatives, long-term management will be
required, including monitoring of the effectiveness of the recovery
and treatment system. During operation of the treatment system,
monitoring of surface water, ground water, and treated effluent
will be required. The potential for contaminants to exist as a
separate, dense phase in the bedrock aquifer will require that
ground-water recovery be conducted for a prolonged period, and can
be evaluated at each of the five-year effectiveness reviews.
i
(
Reduction of Toxicity, Mobility or Volume
Alternatives GW-l and GW-2 provide little reduction of
toxicity, mobility and volume as neither alternative contains the
contamination on-site. This allows only for the existing volume
76
-------
of contaminated ground water with its inherent toxicity, mobility
and volume to be collected and treated. Alternative GW-5 is
expected to provide the highest degree of toxicity, mobility or
voiurr.e reduction because of the additional reduction in VOC level
in the aquifer by bioreaediation. The ground-water treatment
systems in Alternatives GW-3 and GW-4 are anticipated to provide
fairly equal reduction in VCC levels as compared to Alternative
GW-5.
Implementability
Implementation of Alternative GW-5 presents potential
obstacles relative to technical feasibility. This alternative
requires a substantial degree of permitting, and bioremediation is
an innovative technology with associated uncertainties for
reliability, ease of adding additional remedial measures, and
construction/operation. Potential problems associated with
Alternatives GW-3 and GW-4 are not expected to be significant.
Alternative GW-4 is a less widely used method. Alternative GW-3
is expected to be the most reliable of the treatment systems
considered.
Cost
Alternative GW-3 provides the most favorable costs (relative
to Alternatives GW-4 and GW-5) and provides essentially equa
benefits relative to Alternative GW-4 and somewhat lesser benefits
than Alternative GW-5, which costs substantially more. The costs
for each alternative are better defined in the FS.
State Acceptance
The Commonwealth of Pennsylvania has concurred with the
selected remedy.
Community Acceptance
A public meeting on the Proposed Plan was held on May 2, 1991,
in Willieuuport, Pennsylvania. Several comments were received at
the meeting. Community acceptance is more fully assessed in the
attached Responsiveness Summary. The Responsiveness Summary
provides a thorough review of the public comments received on the
RI/FS and the Proposed Plan, and EPA's responses to the comments
received.
77
-------
Selected Remedy
Based upon the consideration of the requirements of CERCLA,
the findings of the RI/FS, the detailed analysis of the
alternatives, public comments, and other documents set forth in the
index for the Administrative Record, the remedy selected for
implementation at the AVCO Lycoming Site for Operable Unit 1 is
Alternative GW-3, ground-water recovery, chemical treatment for
metals, air stripping, emissions controls, and discharge of treated
water. Alternative GW-3 represents the best balance among the nine
evaluation criteria.
Goal
The goal of the selected remedy is to restore contaminated
ground water to its beneficial use, which is, at this Site, a
potential drinking-water supply. Thus, ground water will be
treated until contaminant levels reach background, MCLs, or non-
zero MCLGs, whichever are lower. Based on information obtained
during the RI, and the analysis of all remedial alternatives, EPA
and the Commonwealth of Pennsylvania believe that the selected
remedy may be able to achieve this goal.
The selected remedy will include ground-water extraction for
at least 30 years, during which time the system's performance will
be carefully monitored on a regular basis and adjusted as warranted
by the performance data collected during operation. Modifications
may include any or all of the following:
a) at individual wells where cleanup goals have been attained,
pumping may be discontinued;
b) alternating pumping at wells to eliminate stagnation
points;
c) pulse pumping to allow equilibration of the ground-water
system and to encourage absorbed contaminants to partition
into ground water; and
d) installation of additional recovery wells to facilitate or
accelerate cleanup of the plume.
To ensure that cleanup goals continue to be maintained, the
ground water will be monitored at those wells where pumping has
ceased eyery five years following discontinuation of pumping.
i
Performance Standards
In order to restore contaminated ground water to its
beneficial use, the remediation system implemented under the
78
-------
selected remedy shall operate until Site-specific remediation goals
are achieved. Thus, ground water would be treated until the
contaminant levels reach background, MCLs, or non-zero MCLG-
whichever are lower.
Background concentrations for the contaminants of concern will
be determined by complying with the procedures for ground-water
monitoring as outlined in 25 PA Code S264.97. In the event that
a contaminant is not detected in samples taken for determination
of background concentration, the detection limit for the method of
analysis utilized with respect to that contaminant shall constitute
the "background" concentration of the contaminant. As of the date
of this ROD, the appropriate methods and their detection limits are
as follows.
Contaminant Method Detection
Limit(ug/1)
Trichloroethylene 601/602 0.12
1,2-Dichloroethylene " 0.10
vinyl Chloride " 0.18
Barium SW-346/7000 (Furnace) 2
Beryllium " 0.2
Cadmium " 0.1
Lead " 1
Manganese " 0.2
Hexavalent Chromium " 1
If implementation of the selected remedy demonstrates, in
corroboration with hydrogeological and chemical evidence, that it
will be technically impracticable to achieve and maintain the
remediation goals throughout the area of attainment (which will be
the edge of the site property where contamination is furthest
detected), the EPA in consultation with the Commonwealth of
Pennsylvania, will amend the ROD or issue an Explanation of
Significant Differences to inform the public of alternative
remediation goals.
The discharge levels for contaminants in the treated ground-
water effluent will be determined by EPA in consultation with PADER
as part of remedial design in accordance with the substantive
requirements of Pennsylvania's NPDES program.
Summary of the Selected Remedy
r
As discussed under the Description of Alternatives section,
the selected remedy consists of on-site ground-water containment,
recovery and treatment. Under this alternative, ground-water
recovery wells shall be installed on the downgradient side of the
facility to contain contaminated ground vater and control further
79
-------
off-site migration. The contaminated ground water shall be
recovered through a series of existing and newly installed recovery
wells. The recovered ground water shall be chemically treated for
metals and air stripped for VOCs. The vapor phase from the air
stripper shall be treated by the best available control technology
and the treated ground water shall be discharged to Lycoming Creek.
In addition, institutional controls have been added to this
alternative to limit future property use.
The selected remedy will only address that portion of the
contaminated ground water that exists on-site (Figure 14) . The
off-site contaminated ground water will continue to be treated
through the existing off-site ground-water recovery and treatment
system in accordance with the COA between PADER and AVCO Lycoming.
The selected remedy will not address contaminated soil at the Site
because it does not pose a risk to human health or the environment,
but the fact that it will remain and is considered a waste means
that there is a statutory requirement to review this situation
every five years.
Statutory Determinations
Section 121 of CERCLA requires that the selected remedy:
be protective of human health and the environment;
comply with ARARs;
be cost-effective;
utilize permanent solutions and alternative treatment
technologies or resource recovery technologies to the
maximum extent practicable; and
address whether the preference for treatment as a
principal element is satisfied.
A description of how the selected remedy satisfies each of
the above statutory requirements is provided below.
Protection of Human Health and the Environment
Based on the risk assessment, this remedy will be protective
of human health and the environment over time as ground water
containing site-related contaminants would not move across the Site
boundary. Recovery and treatment of ground water at the southern
site boundary will permanently remove contaminants from ground
water beneath the site. The treatment system is expected to
provide adequate treatment to achieve ARARs for discharge. This
alternative will reduce the concentrations of site-related
compounds in the ground water beneath the site; however, the
ability to attain ARARs in the two aquifers via long-term ground-
water recovery and treatment is not Known. A more comprehensive
ground-water recovery system is proposed in this remedy, in
80
-------
-------
comparison with current recovery efforts. Therefore, the mass of
contaminants that is currently leaving the plant property in the
ground water, and the risk associated with these contaminants
(assuming future hypothetical ground-water use) will be
significantly reduced. This remedy will achieve the remedial
action objectives over time via ground-water recovery and
treatment. No unacceptable short form risks or cross-media impact
will be caused by implementing the remedy.
Compliance with Applicable or Relevant and Appropriate
Requirements
The selected remedy of recovery and treatment of ground water
will comply with all chemical-, location-, and action-specific
ARARs pertinent to this action. Except where specifically noted,
the site-specific limitations to the following ARARs will be
identified in the remedial design phase.
1. Chemical-Specific ARARs
a. Chapter 123 (25 Pa. Code SS123.1 et.seg.) - This
chapter on "Standards for Contaminants" sets forth
requirements for fugitive emissions, including open burning
and demolition activities; specific limitations for
particulate matter sulfur dioxide, odor, and visible
emissions.
b. Chapter 127 (25 Pa Code SS127.1 et.seq.) - This
chapter on "Construction, Modification, Reactivation and
Operation of Sources" requires the use of Best Available
Technology (BAT) for control of new sources, plan approval
and operating permit requirements, and special requirements
for sources in nonattainment areas.
c. Chapter 92 (25 Pa. Code SS92.1 et.seq.) - This
chapter sets forth provisions for the administration of the
NPOES program within Pennsylvania, and establishes criteria
for the content of NPDES permit applications, effluent
standards, monitoring requirements, standard permit
conditions, public notification procedures, and other related
requirements.
d. Chapter 93 (25 Pa Code SS93.1 et.seq.) This chapter
sets forth general and specific standards for the quality of
Pennsylvania's waters and includes specific water quality
criteria and designated water use protection for each stream
in Pennsylvania. It is reviewed and updated, as necessary,
at least once every three years.
e. The Safe DrinJcing Water Act Maximum Contaminant-
Levels (40 CFR Part 141) . This sets forth the Federal
82
-------
Standards for several chemicals including the RCRA MCLs,
adopted to protect public drinking water systems. Standards
will be considered and used in characterizing human healt
risks associated with possible contaminated groundwater usec.
for public consumption.
f. The Pennsylvania Safe Drinking Water Act of 1984 (25
PA Code 109 et. sea;.) State Act which established drinking
water standards at least as stringent as Federal Standards.
g. The Pennsylvania ARAR for ground water for hazardous
substances is that all ground water must be remediated to
"background" quality as specified by 25 Pa. Code Sections
264.90 through 254.100, and in particular, by 25 Pa.Code
Sections 264.97(1), (j) and 264.100(a)(9). The Commonwealth
of Pennsylvania also maintains that the requirements to
remediate to background is also found in other legal
authorities. The method by which background levels will be
determined is set forth in the Performance Standards section
of this ROD. Such background levels shall be attained as part
of the Selected Remedy, unless it is demonstrated that
attaining such levels is infeasible, or otherwise waivable
under CERCLA Section I21(d), 42 U.S.C. Section 9621(d).
h. The National Emissions Standards for Hazardous Air
Pollutants (NESHAPs) set forth at 40 C.F.R. §61-64(b) and
promulgated under the Clean Air Act, 42 U.S.C. §7401, contaj-*
an emission standard for air stripping vinyl chloric^
manufacturing plants that is relevant and appropriate to the
air stripping-. The vinyl chloride emission standard is 10 ppm
(average for 3-hour period).
2. Location-Specific ARARs
No location-specific ARARs have been identified with respect
to this Site.
3. Action—Specific ARARs
a. To the extent that new point-source air emissions
result from the implementation of the remedial alternative,
25 Pa. Code Section 127.12(a)(5) will apply, requiring that
emissions b« reduced to the minimum obtainable levels through
the use of best available technology (BAT), as defined in 25
Pa. Code Section 121.1.
1 b. Treatment and discharge of contaminated ground water
to Lycoming Creek will cause the requirements of
Pennsylvania's NPDES program to apply. Those requirements, as
set forth in 25 Pa. Code Sections 93.1 through 93.9, include
design, discharge, and monitoring requirements which will be
met in implementing the selected remedy.
83
-------
c. The ground-water extraction and treatment operations
at the Site will constitute treatment of hazardous waste
(i.e., the ground water containing hazardous waste), and will
result in the generation of hazardous wastes derived from the
treatment of the contaminated groundwater (i.e., spent carbon
filters from the air stripping operation). The remedy will
be implemented consistently with the requirements of 25 Pa.
Code Part 262 Subparts A (relating to hazardous waste
determination and identification numbers), B (relating to
manifesting requirements for off-site shipments of spent
carbon or other hazardous wastes), and C (relating to
pretransport requirements; 25 Pa. Code Part 263 (relating to
transporters of hazardous wastes); and with respect to the
operations at the site generally, with the substantive
requirements of 25 Pa. Code Part 264 Subparts B-E, F (in the
event hazardous waste generated as part of the Selected Remedy
is managed in a surface impoundment), G, I (in the event that
hazardous waste generated as part of the Selected Remedy is
managed in containers), J (in the event hazardous waste
generated as part of the Selected Remedy is treated or stored
in tanks), and K (in the event hazardous waste generated as
part of the Selected Remedy is treated or stored in surface
impoundments).
d. The land disposal restrictions set forth at 40 C.F.R.
Part 268 are applicable to the management of hazardous wastes
(including spent carbon filters from the air stripping
operation) generated as part of the Selected Remedy.
e. 29 C.F.R. S1910.170 sets forth applicable
requirements regarding worker safety in the handling of
hazardous substances.
f. 49 C.F.R. 5171.1-171.16 sets forth applicable
requirements regarding off-site transportation of hazardous
waste.
g. The requirements of Subpart AA (Air Emission
Standards for Process Vents) and BB (Air Emission Standards
for Equipment Leaks) of the federal RCRA regulations, 40
C.F.R. Sections 1030 and 1050, are relevant and appropriate
(and, depending upon the levels of organics in the extracted
ground water and treatment residuals) may be applicable to
the air stripping operations under the Selected Remedy. These
regulations require that total organic emissions from the air
strapping process vents must be less than 1.4 kg/hr (3 Ib/hr)
and '2.8 mg/hr (3.1 tons/yr).
84
-------
4. ether Criteria. Advisories, or Guidance TO Be Considered
In determining the selected remedy in this ROD, EPA use<
the site-specific guidance documents set forth in the index
to the Administrative Record accompanying the Declaration to
this ROD. i
Cost Effectiveness
Alternative GW-3 is cost effective as the selected remedy,
when compared to the other alternatives. A detailed cost breakdown
for all components of the alternative is presented in Table 20.
Preference for Treatment as a Principal Element
The selected remedy satisfies the statutory preference for
remedies that employ . treatment as a principal element to
permanently reduce toxicity, mobility, or volume of hazardous
substances. The selected remedy addresses the risks posed by the
ground water associated with the Site through use of treatment
technologies.
Utilization of Permanent Solutions and Alternative Treatment
Technologies to the Maximum Extent Practicable
EPA has determined that the selected remedy represents the
maximum extent to which permanent solutions and treatment
technologies can be utilized while providing the best balance among
the other evaluation criteria. Of the alternatives that are
protective of human health and the environment, the selected remedy
provides the best balance in terms of long-term and short-term
effectiveness and permanence; cost; implementability; reduction in
toxicity, mobility, or volume of hazardous substances through
treatment; state and community acceptance; and the statutory
preference for treatment as a principal element.
The selected remedy utilizes the technology of extraction and
treatment to reduce the volume and toxicity of hazardous substances
in ground water. In the short-term, the risks posed by direct
contact with contaminated materials present during remedial
activates and afterwards, and the potential ingestion of ground
water will be avoided through the implementation of institutional
controls., For the long-term, the ground-water extraction and
treatment- will return the ground water to levels that meet federal
and state criteria. The treatment component of the Selected Remedy
is easily implemented.
85
-------
T.bU 20
Alternative GW-3: Ground Water ColUclion, Chemical Treatment lot
Air Stripping. Fume Incineration. Mid (Mscharga or Traalad Walar
Item
Estimated Capital Coil
Description
Recovery Watts
oo
cr>
O
00
go 33
OO
Recovery Pump*
CenkaJ and Eastern
Plant Areas
Cental and Eastern
Plant Areas
Recovery Wees • Western Plan! Area
Recovery Pumps - Western Plant AIM
Bedrock Recovery Wefts
Bwtrocft Recovery Pumps
SMa PiepwsMon
WMIMR InNusnl EquaNzalton Tank
East and Cent IntuarM EquaNiaaon Tank
Piocesa Pumps
Process Pumps
Metals Removal/Recovery TiealabUly
Chemical PieciplUtton System
Sampler
Flow Meier
Plpmg «woogh lacNMy to EquaUiallon
Tanks
Plptng kom WWTP to OMver Sfeeel
Manholes
Horizontal Boring of Piping
Horizontal Boring Pits (6)
Pipe Bedding
Trench trough plan! lacttly to WWTP
InslaM 22
30 N deep
22 pumps and conkoto.6 gpm ea. 0 5 HP
bislal It weas. 30 It
II pumps and conkofa. • gpmea. 05 HP
(ratal 3 deep weas
3 pumps and confeolB. IS gpm ea. I 0 HP
MobHUatton/DemoMllzallon
200Ogafton cap. I FHP w/30 mm ret wne
SOOOoaBon cap. I FHP w/30 mai ret ante
2 TO gpm • 60 N head. 20 HP
2 250 gpm 9 60 N head. 75 HP
TrealabMly study
M gpm system as manufactured by Andco
(SCO or Sigma
Vonlurt Now measuring device
3710 N of 4 In dU PVC pipe
500 N of 12 to dU gravity sow RCP
2 precast concrete 4N«4lti4N w/cover
ISO N of pipe bored under or uM
• Ni«Ni4n AM . totasng 75 cy
10 to deep tod sprtogHne of pipe M 400 B.lftcy
4 N deep. 2 It wide. 3S6O ft long
Unit Cost (I)
S.ftOOes
6.000M
S.BOOee.
e.OOOes
36.700es
6.600es
Lump Sum
e.OOOes
l&.OOOes
a.OOOes
6.300es
IOO.OOO esl
Lump Sum
Lump Sum
Lump Sum
IS/11
13/11
1.7SOes
40O/II
30/cy
23/cy
4 50/cy
Insulted Cost (|)
120.800
132.000
84.800
00.000
110.100
10.500
20.000
a. ooo
15.000
12.000
12.800
too.ooo
318.000
2.000
2.000
55.650
8.500
3.500
60.000
2.300
400
4.750
Paqu t ol 2
-------
-'> conl'd
OW-3: Ground Wat* CotUOton. Chemical lr««im*4il |o« aUUIi.
AW Stripping. Fu»« IncliMiatto*. a*d DUcft«*9« ol Ti**u4 W*Ui
OO
Tianch kom WWTP to Obvar Start 4 • d»*p. 3 H wtda. 4OO ft long 4 M> /cr 000
Ti«nch BacfcliMng and Compaction I ISO ey «nd S% •lal^^* ( p^« vo* A bed ) 2S /cy 28 /io
Fllliailon ~- 3 batk«l Mtois 4 ooo M 12.000
Ait SklppM I 4 H dU 2O H p*dkM< S**n 68 000
Fum« Inckwiatton I »kid mounted to« 1300 C!M oMgM lu«np St«n 227.400
Pi«tob«kc«lMl BuMding Con*oi«. lab. and MTM* aooMtoitM. MO »l 37M/*I 21000
Pumpc t pump and I tp«i* «5OO 00 •• 13.000
Piping 2ft i ol 4 In dla PVC pip* 15/11 _ 400
303.100
Total Dtret CMMtntctt«« CM! (1DCC) l.33a.40«
EngtMMttng. Laoat. HaaMi a Sat»ty, ami
Comhuctton Man apt mart • 26% al TOCC _
BualoUl l.»l«.00«
Total E*UM«to4) M«U«*d C«»l w/3Tfc CMHte««Mcy (»OM»<»< la I •«*•••)
*!lie estimated capital cost in the Feasibility study u.is lia.scd on tlie use i>l I IIIIIL- i nr I m:i .11 Ion ,i:.
a method of emissions control from the air strippers. Th I s tost may change- II l( Is del t:i mliu-il
th.it a different method of emissions control is more stilt.ihle based on the llest Demonstrated Av.i I l.il> I
Q Technology (BDAT).
00
00
I'aqo 2 ol 2
-------
TabU 2(} (ci)iitM)
Alurnallv* GW-3: Ground WtUi Collection. Chemical Iraaimanl lot kUlala.
All Stripping. FUM* Inclnaiallon. and CMtchaig* ol Traalad Walar
lallmalad OAU Coal
Hum
FtMl
Power
Iron Predptaton Opwatton
Labor
ClMintcate
SoMtta DtapoMl
Ouutd* Analy** VariNcatton
Ftv« Yaai PartMn
Equipment MaMananca
UnM Co»l (|)
21.000 gal/yr | 00/gal
274.300 kwtt/yr 0 10 /kwh
34.669.000 oaJkMM 0 40 /IOOO
6240 hour* 30 00/hi
Lump Sum tor mala* lamoval IO.OOO
40 lona/yr 324 /ion
12 tamptaa 1,200/tamp
Annual ooal aqutvatanl ol 6 y»ar raviaw •> 7.800
$20.000 aadi tor 30 yaara
3%otTDCC
Tola! EaMaMla4 AMMW! O4M Coal «/3t% ConllM«aMcy
Piaaanl Wartk al OMI Ceal (M yaan 6> •%)
Annual OtM Coil (|)
21.000
27.4OO
gal 13.000
167.200
10.000
13,000
14.400
7.800
48.000
44*.M6
CO
oo
Tola! PraaMl War* - CaaMal Coal aa4 OaM Caat (36 yaara •> »%)
t.Ml.llt
-a
08
OO
-------
tccur.er.tation of significant Changes from the Proposed Plan
The Proposed Plan for the AVCO Lycoming Site was released foi.
public comment on April 17, 1991. The Proposed Plan described the
alternatives studied in detail in the Feasibility Study, presented
to EPA in March, 1991. In the Proposed Plan, EPA selected a remedy
that included additional on-site and off-site ground-water
remediation. During the public comment period, EPA received
numerous comments in support of not performing additional off-site
ground-water recovery as part of this ROD. After careful review
of these comments, which included a hydrogeologic evaluation of the
off-site ground-water plume, EPA has decided not to include
additional off-site ground-water remediation as part of this ROD,
as originally set forth in the FS. This decision is based on the
need for additional studies to determine the most appropriate
action to further recover and treat the off-site contaminated
ground water. Therefore, the off-site contaminated ground water
will be a separate operable unit (OU-2) that will be addressed in
a future ROD.
39
-------
?.E S ? 2 N" 5 IVE>:ESS S L'MXAR Y
FCR. THE
PRCPCSEZ REMEDIAL ACTICN PLAN
Cut-ine 1
Background 2
Part I: Summary of Corrj7.er.tors' Major Issues
and Cor.cerr.s 3
A. Health Concerns 3
3. Remedial Alternatives 4
C . Ground Water Cleanup 6
D . Administrative Record F lie 6
E. Technical Assistance Grant Process T
Part II: Comprehensive, Technical and Legal Response to
Significant Comments 3
-------
3 •"* '^ ** ~ w " ° '^ — s s — *^.n c *5 s c c n H3 " ^ ~rcss rH^s^
.e r.ur. i z ipa
" s c r1. r. i c 3 1 r^sccr. ss iccurr.sr. ".
-------
the Avco '—'<' — C.T.Ir.~ Site has ceer. li.~i.~2ci.
To obtain public input or. the Proposed Remedial Action Plan
1", 1391 to Xay 15, 1991. lr. May 2, 1951, EPA held a public meet;
to present, the plan, answer questions, ar.d receive oral oor-.-er.ts 2
cruesticr.s . E?A also crovided cublio meetir.c resccr.se cards wr.io'r.
allowed rr.eetir.g atter.oees to rr.ake cc~rr;er.ts or. tr.e cards ar.d ser.d "
to EPA. Tr.cse ir. atter.car.oe at tr.e rr.eetir.c ir.c —uded loca_ arsa
residents, state and Izoal officials, news rr.edia representatives,
'"oc*"os*=in""a"" ; v-^s -^^.—« Z~~" a*"d *^°cr°sentatives from T-^xtron I-'/corr.ir
EPA notified looal rr.edia, area residents and Federal, state,
and local officials of the May 2, 1991 public meeting through a
oub1i ~ no~io° ann oun o °~an~ cub1i s hed in the AD r i1 17 1991 edi t i cr
of the siilliaKSpcr- S<~~ Gazette. In addition, EPA established a
site information repository at the James V. Brown Library in
Williamsport. The repository contains EPA's Administrative Recorc
File for the site as well as all documents used in the selection
-------
PART I: SUMMARY OF CCMMENTORS ' MAJOR ISSUES AND CONCERNS
This secti" prcvi^ec = 3u.--T.ary cf r cm-enters ' ~a~cr i33ues
ir. i 7 : r. ce rr. 3 ar.c, -sxc r-=33 ly ii.ir.ewlez-es ar.z resc ;.-. ds to t.~. C3^
-2 ma " r -33u^3 ar.:: ~
• a — s
A. Health Concerns
3. Remedial Alternatives
C. Ground Water Cleanup
3. Administrative Record File
E. Technical Assistance Grant Process.
A. Health Concerns
• A citizen askec. if the Avco lyccming Site is an -exception to tr.e
perception tr.at when people think of a Superfund site they thin<
of some risk to tr.e environment, to public health, and safety.
".-._-•? : :.'o, the S-perfur.o. program mandates I?A to also
- * _ — . ..•'ci^'^.w~^/ — " ."A ... ^* o — ^.. ^ '/'*•.» ^ *. ^* --»S — — —..i — ..£ _..tcj
ccter. tial ris<3 of ar. ir. ii'/iiual oor. tract ir. - oar. oer, f;r
13 x a rr. c . *^ c o *" ri a ** ~ r.~* c r a s ^ ^. * a r*. i i. r*. *" 't ° f u r u r °
A citizen as
-------
a sensitive perscr. such as an individual who -ay have asth.-.a,
for example, the elderly, and some sensitive sub-popuiat icr.s .
A citizen asked if there .-.as ever been an epidemiological studv
- ~ cancer rates ~ ~. ~ h e 3 i ~ a a*"aa .
"nsg : ..-.ere is current.-/ a health study assessment being
acne by t.-.e Pennsylvania Zepartment cf Health which involves
epidemiologists. This survey will be available for public
• review as soon as it is released.
intake of the area residents.
Z?A Response : The air rr.cdelin- has taken this into account in
evaluating the maximum areas where concentrations would occur.
• A citizen asked if an ecidemioiogicai studv or a health
assessment will be conducted at the site, and if this testing
will be completed prior to the Record of decision.
EPA Response: An epidemoiogicai study will not be conducted at
the site, however, a health assessment will be conducted. The
main difference between an epidemological study and a health
assessment is that the study develops new data from interviews,
biological samples, demographical data, etc. A health
assessment only uses data already available from EPA's studies
of the site.
• A citizen asked if there is a technology available to accomplish
air stripping that does not vent chemicals into the air.
EPA Response: Air emissions control will be part of the
remediation; no harmful levels of VOCs will be vented to the
air.
B. Remedial Alternatives
• A citizen asked EPA to define the ultimate objectives of the
thirty-year cleanup process .
EPA Response: EPA intends to achieve the cleanup goals which will
be identified in the Record of Decision. EPA will issue a
Record of Decision at the end of June which will require a
contaminant concentration equal to that of background ground
• A citizen asked if the off-site cleanup would affect the
residents.
EPA Response: No, the off-site cleanup will not affect the area
residents other than potential for releases of volatile organic
compounds during the installation of wells. This will be
-------
• a •
.-• exposure 2: loxicity ir.rc rr.at icr., tr.er. we r.ave
a — -" a
: _3sue of c rote ot iver.es s is re-addressee at that
o i t 12 e r. a 3 .< e o 11 ^ r.-. 2 c r. o, u c ~ e d a r. i r. z e c s r. i e r. ~ a c c r a i s a
c- .as--— * - ^
. n o o n n e c 11 o r. w 11 n issuing its .-. e c o r o. or _ e c i s i o r
.oteo an ir.cecer.oent oost estimate to confirm the
£r A Pespcr.se: Z?A sr.culi have ar. operaticr.al grour.i wa^er
reccverv ar.i treacr.er.i S'/sterr, ir. clace wichir. acp ro.xima _e -'.' ~w
'•'ears cf "r. e ?. e — c r d cf Zecisicr*..
• A citicer. asked if a.-.y ctr.er a.i err.az ives were ceir.g ccr.siiere-
to prciect tr.e air as well as tr.e wa-er.
EPA Respcr.se: Yes, EPA is rcr.cerr.ed wi-h air quali.y as well as
water quality ir. tr.e site area. EPA will tr.erefcre, place son
ccr. trols c r. too cf "he air striccers tr.at will crevep.c
* »^.—. j—fc fc
volatilization of the ccr.pcuncls during the stripping process.
• A citizen asked if any study had been conducted regarding the
synergistic effect of acditicr.ai toxics released by air
stripping, the Avco facility, and the other industries in the
area .
EPA Response: No, it is not necessary to evaluate synergism. A
emissions controls will be part of the remedial action for
operable unit one of the Avco Lycoming Site.
i
• A citizen asked if the duties of the Community Relations
Coordinator and the Remedial Project Manager will continue to
reside in Pennsylvania.
Z?A Respor.go: The duties of the Community Relations Coordinate'
have been assumed by Mr. Patrick Gaughan in Wheeling West
-------
Virginia, however, Eugene 3er.r.is will continue to carry cut the
duties of the Remedial Prefect Manacer in Philadeiohia.
A citizen asked if tr.s crcccssd rerr.eci'.' is selected from
alternatives studies cy Avcc cr cy an independent E?A studv.
• A citizen asked if proposals were considered
affected earth.
;a soi- was
a*"*^if ^^"> *^-**r~v ••-• « ..... ^^«<^.^_V'...,.'^*lvt
C. Ground Water Cleanup
• -A citizen as
-------
• • — ;S -• — — -» — —« £3 ••« W ' " ~ ~ ~ O -» ' ^ a — • . « .3'
~- -1 r^cruire the ACJT. in ist rat ive ?.ec:
zz cur.er.t 3 tr.at were -sei in tr.e ~a!<.
3 3 rr. s r*. ~ w n i. c n i*. 3 s 3 i. r1* c s
A c*"^.z*ar'. — s V. ^^ ci wp. */ "ns A ^i rr. * n • 5 c ^ 2 ~ i. v ° ?-^cc^i F" — • *^ s^^^^s *""
alternative tr.ree is preferred, while ar. April 1", 1391 news
ar^i^le *'*3i'*a""':ai " n a " a 1 " ** r r1. a t i v * ^c*ur is cr0*0^'*'0'^
is a i i s c r e c a r. c v c e t w e e n the AcLrr. 1 r. i s t r a 1 1 v e
P.eccrd File ar.a tr.e Acril l~th r.ews article regarding the .".•_: .rJ:er
-~ c "j^o — S»-O<;Q»"'-O.^' ^"••^'"^^••••/ia^.p^taACfa ^ ** •" «^vf^ •••^•v..^ »•>» • ** 1* f ~*. v .*a^
is ~ '~ & sarr. e
and onl the nurriers are
• A citizen as
-------
are applied for and awarded during the Remedial Investigation.
feasibility Study stage at the site, however, there have been no-
formal limits set against awarding TAGs after the stage has
passed.
• A citizen asked how Icr.j the TAG ace 11 cat ion crocedure takes.
Z?A Pqspc.-.sg : The TAG acclicaticn orocess can take uc to five or
six mcr.ths .
• A citizen asked if there is ar.y r.etwcr:< cf TAGs withir.
? e r. r. s v 1 v a r. 1 a or the ?. e c i o r.
"^he*"0 '~avo b0£ap. less than tar^' ""AGs awsr-ded in EPA
r.eaion III, and there are several for Sucerfund sites in
Pennsylvania, specifically the Paimerton Zinc Site, the C i D
" frcre Sit.
Part II: Comprehensive, Technical and Legal Response to
Significant Comments
Please refer to technical resoonse document.
-------
PART II
R2SPON8IVZNES8 SUMMARY
(technical raaponse)
TABLZ 07 CONTENTS
ION; PAGE
May 1, 1991 letter from ERM to U.S. EPA 1
May 2, 1991 Public Meeting Transcript 10
May 16, 1991 letter from ERM to U.S. EPA 14
May 14, 1991 letter from Williamsport Municipal Water
Authority (WMWA) to U.S. EPA and May 16, 1991 letter
from ERM to U.S. EPA in response to the WMWA letter 16
May 10, 1991 Letter from ERM to U.S. EPA 20
Response to U.S. EPA and PADER Comments:
15 January 1991 Draft Remedial Investigation Report for
the Textron Lycoming Williamsport Facility 22
Response to U.S. EPA and PADER Comments:
31 January 1991 Draft RisJc Assessment Report for the
TexHron Lycoming Williamsport Facility 31
Response to U.S. EPA and PADER Comments:
15 March 1991 Draft Feasibility Study Report for the
Textron Lycoming Williamsport Facility ... 36
-------
AVCO LYCOMING (TEXTRON LYCOMING), WILLIAMSPORT, PA
2.0 RESPONSIVENESS SUMMARY
Source Document: May l, 1991 Letter from ERM to U.S. EPA
Ground-Water Use/Risk Assessment
1. The RP expressed concern that insufficient emphasis was
made regarding the fact that current users of ground water
pumped from the Williamsport Municipal Water Authority
(WMWA) wells do not face any additional potential risks,
as this water is treated before introduction into the
water supply system. The emphasis should be placed on the
fact that the risks discussed in the Proposed Plan are for
a hypothetical scenario that does not presently exist
(i.e., drinking untreated ground water over an extended
time period).
EPA acknowledges this concern. It will be noted in the
Record of Decision (ROD)that siterisks are due to
hypothical exposures.
2. The RP suggested that EPA express a range of values for
the hypothetical future risks and corresponding estimated
increased incidence of cancer in the Proposed Plan and
subsequent revised pages. The RP provided Table 1 which
lists the correct hypothetical cancer rates based on the
correct hypothetical risks.
EPA acknowledges receipt of the Table and the changes are
reflected in the ROD.
3. The RP states that there is no current threat to public
health or welfare, because the WMWA well field has been
provided with treatment and the plume has been contained
by the Third Street recovery well. The RP further states
that due to these factors, the statement in the Proposed
Plan (page 8, paragraph 1) "Actual or threatened
releases...present a current or potential threat to public
health, welfare, or the environment11 should be corrected.
At this time. BPA diaaareea that there i« no current or
envir*7riB^pt« Until additional data from Monitoring are
obtained ^nd Modeling i» performed* BPA cannot modify the
statement.
4. The RP requests that the first sentence on page 8,
paragraph 2 of the Proposed Plan be modified to read "At
this site the most significant potential future risk...,"
-------
rather than "At this site the most significant risk...."
The RP argues that a risk to surrounding populations under
current conditions (i.e., treated water) is"not
applicable.
5PA notaa that "aoat significant" is used in this sentence
to mean "primary" vith respect to riafca posed bv the site.
No reference to the tiae the risfc aav be posed is implied.
5. The RP notes that page 8, paragraph 5 of the Proposed Plan
should be modified to state that institutional controls
should encompass future land use and untreated ground-
water use rather than only implementing institutional
controls for exposure to contaminated soil.
SPA recognises the need for institutional controls for
future land use and untreated ground-water use and shall
incorporate the addition to the ROD.
Feasibility Study
5. The RP requests clarification of page 2, paragraph 1 of
the Proposed Plan regarding whether a third edition of the
Feasibility Study (FS) report would be retired or in fact
the revised FS pages already submitted to EPA would be
sufficient.
doeg not require a revised edition of! the Feasibility
Study report. The revised pages will besufficient to
satisfy BPA's requirement.
Ground-WaJ^er... Recovery
7. The RP commented on the Proposed Plan statement (page 15,
item 3) that "the additional recovery and treatment of the
contaminated off-site ground water will help in restoring
the quality of off-site ground water in the overburden and
bedrock." The RP does not concur with the assumption that
additional off-site ground-water recovery and treatment
can be implemented in a technically sound manner without
further study of the performance of the proposed on-site
recovery system. However, the RP states that since there
is no risk to ground-water users, the plume is stabilized,
th« WMWA well field is protected by the Third Street well,
the WMWA system is treated, additional off-site recovery
will not change or decrease the hypothetical risJc in the
shbrt term, and off-site institutional controls can
control future hypothetical risk scenarios.
treat the off-site olmif *,§ * separate Operable Unit
additional data
-------
will be needed to confirm tha statement, but, believes the
ongoing off-site plume containment and contaminant mass
recovery ia effective. Baaed on the results of tha Remedial
investigation and the Feasibility Study, additional off-
site around-vater recovery may be required to mitigate riafca
posed by the ee>n+-»minant plume.
8. The RP commented that the statements (page 8, paragraph 3,
last sentence; page 11, paragraph 2 and page 13, paragraph
2) regarding the need for additional off-site ground-
water recovery of the Proposed Plan are inaccurate. The
Proposed Plan states that "the off-site contaminated
ground water...recovery and treatment systems...will be
enhanced by additional recovery." The RP stated that
there are insufficient data presently available to support
this statement and there has been no opportunity to '
evaluate the effect of pumping the on-site recovery system
proposed in the Feasibility Study on off-site ground-
water quality over time.
The RP further states that the there are presently
insufficient data from the aquifer system to determine the
need for an upgraded scheme or to optimize well
configuration, should additional off-site recovery be
required in the future.
EPA will treat the off-ai^t Pl"pi* >a » separate operable unit
which will be addressed in m furture ROD and based en
additional studies. BPft understands that additional data
will be needed to confirm the statement, but believes the
recovery is effective. Based oa the results of the Remedial
Investigation and the Feasibility Study and data from similar
sites* additional off-site ground-water recovery may be
>aed bv the conti
it affects the off-aite aquifers.
Contamination
9. Th« RP requests that the statement that "the ground water
in tha bedrock on-site and off-site is contaminated with
TCE, DCE, and Vinyl Chloride" be clarified to reflect the
limited nature of the bedrock contamination.
statement needs clarification at this time.
10. The RP states that on page 6, the last paragraph of the
Proposed Plan, the value of 19,000 parts per billion
(ppb) should be corrected to 1,900 ppb.
-------
acfcaoirladgaa the transcriotional arror. Tha chance will
ba reflected in the Summary of Site Characteristics section
of the ROD.
Other Cc
11. The RP states that page 2, paragraph 5 of the Proposed
Plan should be corrected to state that AVCO was
acquired by Textron on February 28, 1985, not in 1980.
EPA acknowledges this comment and notes the change. Tha
correction will ba raflactad in taa 8ita Name. Location, and
Description section of the ROD.
12. The RP states that page 5, item 4 of the Proposed Plan
should be corrected as lead is not present above
background levels in soil. In addition, the RP noted
on page 6, paragraph 1 of the Proposed Plan that the
concentrations of lead actually found in the eastern
end of the property were 16.0 and 18.5 parts per
million (ppm), not 169 and 185 ppm, respectively.
This is based on incorrect laboratory results which the
RP rectified in the April 15, 1991 revised Remedial
Investigation report.
EPA acknowledges and nota* this change. The correction wii:
be reflected in the Summary of Site Characteristics section
of the ROD.
13. The RP stated that the sentence on page 6, paragraph 3
of the Proposed Plan should be revised to read "The
direction of overburden ground-water flow is to the
south." The RP noted that the bedrock ground-water
flow is to the southwest.
The Reaedial Investigation report states that ground water
in the shallow aquifer (overburden) floir a oriMarilv in a
southerly direction with Minor components toward the
southwest and •outhaast. Tioruraa within the Remedial
bedrock aquifer is predominantly to the) southwest. EPA
• and notaa this chance. The revision will be
the ROD.
(
14. The RP states that page 7, paragraph 1 of the Proposed
Plan contains an error regarding beryllium values of
samples collected in Elm Parfc. There was only one
sample reported for Elm ParX (MW-32) and the
concentration was 3.5 ppb. Therefore, there is no
range of values as indicated in the Proposed Plan.
-------
EPA acknowledges and notes this change. The correction will
be reflected in the fl»mnt«T-y Of site Characteristics section
of the ROD.
Remediation
15. The RP recommends that EPA include in the paragraph on
page 5, Scope and Role of Operable Units, language
indicating that "extensive remedial actions carried out
by Textron under the Pennsylvania Department of
Environmental Resources (PADER) direction, both on- and
off-site." The RP suggests that a listing of the
remedial actions (i.e., installation of five recovery
well systems with air strippers, extensive quarterly
monitoring, installation of air strippers at the WMWA
well field, and remediation in the old wastewater
treatment area) be included in the plan.
As part of the Administrative Record, this information is
included for public review. Baaed on the scope off the
remediation should be included in the Proposed Plan.
16. The RP states that on page 9, paragraph 2 of the
Proposed Plan, EPA has developed a monitoring
alternative rather than a true "No Action" alternative.
The RP further states that "Because there is no short-
term ground water cleanup under this option, there is
also a need for five-year effectiveness reviews, which
is not costed by EPA in the Proposed Plan."
EPA*s "Guidance for Conducting Remedial Investigations and
Feasibility studies Under CBRCIA" (EPA/540/Q-89/004. October
1988) states "that « no-action alternative aav include some
EPA has not estimated a coat for the five-year effectiveness
reviews in the Proposed Plan and but will discuss them in
the Remedial Alternatives section of the ROD.
17. The RP states that Alternative GW-1, on page 10 of the
Proposed Plan, includes the existing monitoring program
required under PADER's auspices. The comment suggests
that the Proposed Plan should be modified to reflect
this.
i
monitoring i» a component of this alternative. The change
will be reflected in the Remedial Alternatives section of
the ROD.
18. The RP notes that Alternative GW-2 on page 10 of the
-------
Proposed Plan should include proposed restrictions on
future untreated ground-water use in the area overlying
the piuae.
SPA aotas and acknowledges this comment. The change vill be
reflected in the Remedial Alternatives section of the ROD.
19. The R? notes that the annual O&M cost for Alternative
GW-3, on page 10 of the Proposed Plan, should be
$442,900, as noted in the 15 April 1991 submittal, not
3442,700. The extra cost reflects the change in
monitoring well configuration to encompass the eastern
end of the facility requested by PADER.
In addition, the description of this alternative includes
institutional controls but does not include the cost for
these controls. The RP states that in order for this
alternative to be effective, institutional controls should
include limitations on property access and future untreated
ground-water use, not just future property use.
EPA notes and acknowledges thi,? comment. The change vill be
reflected in the Remedial Alternatives auction of the ROD.
20. The RP notes that the annual O&M cost for Alternative
GW-4, on page 10 of the Proposed Plan, should be
$526,000, as noted in the 15 April 1991 FS revision
package, not $525,700. The extra cost reflects the
change in monitoring well configuration to encompass
the eastern end of the facility requested by PADER.
EPA notes
«nt vill
be reflected in the Remedial Alternatives section of the
21. The RP notes that the annual O&M cost for Alternative
GW-5, on page 11 of the Proposed Plan, for this option
should be $650,500, as noted in the 15 April 1991 FS
revision package, not $650,000. The extra cost
reflects the change in monitoring well configuration to
encompass the eastern end of the facility requested by
PADER.
reflected in the R<
22. the RP states that on page 11, paragraph 2 of the
Proposed Plan,the statement,"the recovered ground water
would be. recovered through a series of existing and
newly installed recovery wells" is not completely
accurate. The RP states that the proposed on-site
recovery system was not designed to incorporate
-------
existing recovery wells. The RP further clarifies this
by stating that this does not mean that the existing
well system would be discontinued.
EPA notes and acknowledges tb*« eammant. The chance vill ba
reflected in Remedial Alternatives section of the ROD.
23. The RP suggests that EPA revise the statement on page
11, paragraph 2 of the Proposed Plan to allow for a
determination of the need for air emissions controls
after actual recovered ground-water concentrations are
known. The RP states that the wording ("the vapor
phase from the air stripper would be treated by the
best available control technology") implies that fume
incineration would be required. The RP believes that
if the recovered volatile organic contaminant (VOC)
concentrations are sufficiently low and there is no
unacceptable risk from uncontrolled stripper emissions
from the treatment process, emissions controls may not
be required. The RP suggests that EPA modify the
wording to allow a determination of the need for air
emissions controls after actual recovered ground-water
concentrations are known.
EPA notes that the RP indicated in the Descriptions of the
Alternatives in the Proposed Plan describing air strippers
that air emission control* are a component of the
alternative. No cflimt has been made at this time. An
evaluation of the type of emissions control will be made
during remedial design. At this tin*, it appears that some
type of emissions control will be needed.
24. The RP suggests that EPA modify the last line of
paragraph 2, page 11 of the Proposed Plan where
institutional controls are discussed to include future
property access and untreated ground-water use in
addition to future property use.
re will be
reflected in the Remedial Alternatives section of the ROD.
25. The RP suggests that the Alternative GW-2, as discussed
on page 13, paragraph 1 of the Proposed Plan, be
carried through the evaluation process since component
parts of it could be incorporated in the selected
remedy for the site. The components include the
Institutional controls such as fencing and ground-
water, access, and land use controls.
EPA agrees that institutional controls are needed in the
selected remedy as described in the Remedial Alternatives
-------
gaction of the ROD.
25. The R? suggests that the language in paragraph 2, page
13 of the Proposed Plan be modified to state that the
ability of the alternatives to meet effluent limits
will have to be reviewed after actual implementation.
The RP states that contrary to EPA's statement, it
cannot be determined with certainty that the effluent
limits for the treated ground-water discharge can be
met. This is because effluent limits have not yet been
set by PADER for this discharge.
SPA notes this comment hovever. the effluent linita will set
be by PAD2R during the desicrn stage and will be evaluated
for tfteir efficiency*
27. The RP suggests that the language in paragraph 3, page
13 of the Proposed Plan, which states "the goal of the
ground water remediation is to achieve background
ground water quality as required by the PADER," be
modified. The wording should state "..if it is
demonstrated that ground water contamination
asymptotically approaches concentrations above the
cleanup levels, EPA shall modify the cleanup levels
consistent with that determination. "
EPA believes, that it implementation of the selected remedy
demonstrates, in corroboration with gyflroqeological and
cheaical evidence, that it will f« technically impracticable
to achieve and Maintain the remediation goals throughout the
area of a
contaainat
with
h will be the edge of the aite where
t detected). the EPA in consultation
•alth of
ROD or issue an Explanation of Significant Differences to
Lye aroun
-------
to be consistent with the Feasibility Study report.
EPA notes and acfcnowledges this ce""»«"» The change vill be
reflected in the RiaX Characterization section of the ROD.
30. The RP requests that the language of paragraph 1, page
14 of the Proposed Plan be modified. Surface water is
not a medium which will be monitored. The RP requests
that surface water be removed from the second sentence.
EPA not
-------
Source Document: May 2, 1991 Public Meeting Transcript
21. will off-sire ground-water recovery and treatment be
chosen at the time of the final decision? (See page 9,
lines 5-20.)
Additional off-site ground-water recovery and treatment of
the corn-*™-i,nant pluaa will be considered as a separata
operable unit and addressed by BPA in a future ROD.
22. What is the basis of the estimate for the cost of the
proposed twenty- to- thirty-year ground-water
remediation? (See page 10, lines 4-17.) Will the
estimate of cost be based solely on the AVCO consultant
estimate, or will an independent appraisal be made?
(See page 13, lines 9-10.)
The costs were estiaated by the AVCO Lycoainq consultant
based on years of experience and practice in the field.
In angver to the second Question.. EPA has recently made an
independent cost estimate and confirmed the estimated cost.
33. What is the ultimate objective regarding contamination
at the end of the thirty-year period? (See page 10,
lines 24 and 25 and page 11, lines 1-9.)
EPA expects the ground-water contamination levels to be
equivalent to those concentrations that have not been
impacted by contamination ffroa AVCO Lvcomina (i.e.,
background) or Majciaua Contaainant Levels (MCLs) as defined
bv BPA or risk level! (whichever is the lowest).
34. Are there any data available as to the length of time
groundwater was contaminated prior to treatment being
implemented, and could residents have consumed
untreated, possibly contaminated, water? (See page 13,
lines 11-25 and page 19, lines 1-25.)
The riifca posed in the past were not evaluated prior to the
extension of public water line* or the construction of air
stripping towera. The riafc assess«ent evaluates current and
futura water use. The water drawn fro« the contaminated
yell field is treated to non-detectaJJl* levels before it is
put into the Municipal water supply for drinXinq. However,
priop to treatment being implemented, since the well field
is al*BO the reserve water «7»ttB ff?P the city, past
consumption of non-treated water was a possibility.
35. Will Best Available Technology be used regarding the
air stripping controls and would money be available if
better technology became available? (See page 24,
10
-------
lines 6-25 and page 25, lines 1-6.).
EPA believes that there is always the option of using a
better technology should it become available. The
performance standards to be met will be identified in the
Record of Decision (ROD) and the Remedial Design. These
standards would apply for future use, unless it is found
that health effects are a greater concern than previously
determined. New exposure or new tozicity information vould
allow the ability to re-exanine the current controls in
place in addition to the standard design process. Limits of
the stripping tower controls would also be examined. There
is also, a built-in five-year review period in which at or
after five years of operation, BPA re-«^«V"«a the entire
site to determine if the remediation is still protective.
If it is no longer protective, it is re-evaluated.
with regard to money being avt
addressed during the remedial Phase.
issue wi:
36. What is the situation regarding some residents who have
their own wells and are consuming or using water for
food processing from the contaminated well field? (See
page 30, lines 24-25 and page 31, lines 1-20.)
Based on the remedial investigation. a thorough survey has
been completed which identified any users within the three-
mile radius of the facility. Baaed on this survey EPA
believes that there are no private wells currently in use
AVCO.
37. Explain what is meant by limiting of future property
use? (See page 32, lines 1-15.)
Limits on future property u«e relate to limitations to those
activities compatible with site conditions.
38. Regarding the consideration by EPA for the need of
additional off-site remediation, pending an evaluation
of the effectiveness of the on-site containment, will
the evaluation take into consideration the mass of
contaminants in the bedrock members between the plant
site and Third Street and the approximate travel time
and contamination of the material in that area? What
period of time would be sufficient to evaluate that
strategy? (See page 32, lines 19-25 and page 33, lines
1-14.)
be used to
boundary and Third Btreet and provide some information as to
11
-------
tha aaaa of contaminants. This procaaa la vary difficult.
but tha information gathered as vail as additional riafc
asaeaaaant off-aita would allov tha formulation of a plan to
moat affactivaly eaotura. racovar and traat tha off-aita
contaainatad plume. Tha tiaa gram* conaidarad for
evaluating this procaaa J3 approximately tiro vaara.
39. Will additional studies be cost-effective relative to
actual additional off-site cleanup? (See page 33,
lines 16-25 and page 34, lines 1-7.)
Additional studies should ba banaficial la pinpointing exact
placement of additional off-ait* recovery valla for
effective racovary of tha pluma and •nhancenent of the
cleanup tia« frana.
40. Would it be advisable to consider the expansion of
monitoring the wells to include more points in and
around the public water supply well field? (See page
34, lines 16-25 and page 35, lines 1-6.)
Expansion of th« monitoring valla will b« t*X«n undar strong
consideration. This includes not only additional nonitorinq
in tha vicinity of 81a Parfc or Third 8traat a» a result of
additional studias but also evaluation of how far bavond
41. The off-site pumping from the Third Street recovery
well is presently pumping at a thousand gallons a
minute. Has any consideration or study been given to
the potential of actually pulling more contaminants
into the immediate well field area due to the high
pumping rate? (See page 37, lines 1-5.)
The futura evaluation of tha «ffactivanass of tha on-sita
around-vatar racovary and traitaant systam should provide
inforaation to «aXa this dataraination.
42. Has any consideration been given to the use of any
other off-site wells which might cause the point of
depression to be less extended? (See page 37, lines 6-
10.)
Tha future •valuation of tha affactivanaaa of th< on-aita
to »*Jca this dataraination.
43. Do you have any information update on when air
inversion occurs in this valley? (See page 38, lines
13-25 and page 39, line 1.)
12
-------
air Modeling has taXan this into account in the maximum
areas where concentrations would occur and in that respect
vould have considered any processes auch as air inversions.
44. How far beyond Lycoming Creek does the contaminant
plume extend?
The future evaluation of the effectiveness of the on-site
ground-water recovery and treataent system should provide
information to mafce this determination.
13
-------
Source Document: May 16, 1991 latter froa ZRM to U.S. BPA
43. The RP provided a letter summarizing their rationale for
proposing an intensive On-Site Ground-Water Recovery and
Treatment System as the best remedial alternative.
According to a letter submitted by the RP, "Textron Lycoiaing
wants to see an effective remedial program for the site based
on sufficient information to make an informed remedy choice.
From the time of discovery of contaminants in the ground water
beneath the facility and off-site, Textron Lycoming has
responded by completing an intensive hydrological
investigation of the aquifer system, continuing routine
ground-water monitoring and initiating ground-water recovery
and treatment en-site, and at the Williamsport Municipal Water
Authority (WMWA) municipal well field. The extensive data
gathering and evaluation process that culminated in the
completion of the remedial investigation (RI), the risk
assessment (RA), and the feasibility study (FS) combined with
the routine ground-water monitoring, from the existing
database from which to make a remedial decision. The data
collected indicate that the existing remedial system has
achieved a measurable level of control on the ground-water
system."
The RP proposes to conduct numerical analytical modeling. The
additional technical data resulting from this modeling, in
combination with the selection criteria established by the
regulations, will allow EPA to make an informed decision on
the performance of the system and an assessment of the need
for additional off-site ground-water recovery.
The RP requests that the ROD provide a mechanism, based on the
monitoring data and modeling results, that will evaluate the
need for additional off-site remediation.
At this tim« EPA agrees with the RP tnat the existing and
proposed groundwater recovery «y»to will achieve a
on cont^aia^nt Migration* The off-site
will be treated as * separate operable unit
and addressed by BPA in a future ROD.
46. The RP requests that the performance of the ground-water
remediation system be evaluated based on technically
achievable goals. The RP requests that the ROD reflect EPA's
recognition of limitations on cleanup strategies and the need
to base cleanup goals on best demonstrated technology. In
other words, the ROD should be worded to state that "if it is
demonstrated that ground-water contamination asymptotically
approaches concentrations above cleanup levels, EPA will
modify the cleanup levels consistent with that determination.
14
-------
EPA does not agree with the proposed change at this time.
CSRCLA requires that remedial actions meat applicable or
relevant and appropriate requirements (ARARal of other
Federal and state env* Torin*ntal laws. These lavs include
but are not limited to; The Toxic Substances control Act.
the Clean Water Act, the Safe Printing Water Act, and the
Resource conservation and Recovery Act.
All discharges of treated ground water to Lycominq Creole
should aeet National Pollution Discharge Elimination systani
(NPDB8) requirements developed pursuant to PAPER Bureau of
Water Quality Management standards. The goal of the ground-
water remediation is to achieve background groundwater
quality as required by the Pa. Code Sections 264.90 through
264.100. See comments 128 and *7l of this Responsiveness
for further details.
47. The RP requests that the off-site institutional controls
recommended in the FS be made part of the ROD since the
potential risk to a hypothetical ground-water user exists
and will exist until remediation is completed.
EPA agrees that institutional controls are needed in the
final selected remedy and will incorporate them into the
selected remedy as described in the ROD.
15
-------
Source Docuaent: May 14, 1991 letter froa Williaasport Municipal
Water Authority (WMWA) to U.S. BPA and
May 16, 1991 Letter fron BRM to U.S. EPA in
Response to the WMWA Letter
43. The WMWA submitted a comment regarding whether the present
two-stage air stripping system is a limiting factor with
regard to increasing the well-field capacity from 6 million
gallons per day (MGD) to 9 MGD. (See WMWA Comments l & 2.)
The RP responded to this comment and believes that
nicdif ication of the air stripping system will not have an
impact on the available yield. The RP further indicates
available records do not exhibit that the well field has
ever been used at even its current 6 MGD capacity.
The two-stage air stripping system limits the rate at which
well water can be treated to remove VOCs to 6 MGD, but does
not limit the rate at which the well field can be pumped.
Current plans are to increase the capacity of the stripper
system to 9 MGD by modifying it to a one-stage system. Once
the air stripper can handle 9 MGD, and provided the well
field yields 9 MGD, the WMWA will be assured of this rate of
supply.
BPA cannot respond fully to this commen.t until certain
questionsareanswered.The WMWA »uat provide data
demonstrating that the wall field canreach * yield of 9
MGD. Alao. at a withdrawal rate of 9 MOD,, the impact on the
qroundwater flow regime is liXely to be significant if
pumping_continues over in extended tiae period. The WMWA
These factors will become more evident and important when
the off-site qrouadirmter recovery and treatment la addressed
in the second operable unit in a future ROD.
49. The WMWA noted that the Third Street recovery well pumping
appears to successfully control additional contaminant
migration into the WMWA well field, but expressed concern
that the Third Street recovery well may significantly affect
the recharge capacity of the well field when used for
extended periods of time at rates of 6 MGD or higher. (See
WMWA Comment 3.)
The RP agrees that the Third Street recovery well is
effective in controlling the contamination into the WMWA
well 'field. The RP states that the maximum effect of the
Third Street Recovery Well on the WMWA supply wells could
theoretically be as high as 1 to 1.4 MGD if the Third Street
well is pumped at 700 to 1,000 gallons per minute. The RP
also notes that the water in the Third Street and WMWA wells
is induced recharge from Lycoming Creefc and the Susguehanna
16
-------
River. Therefore, it is unlikely that the Third Street well
has or will have any measurable impact on the WMWA well-
field yields.
EPA believes that the ability of the Third Street veil to
intercept contamination and its impact on the yield of the
WMWA veil field depend on the pumping schedule and pumping
rates from the WMWA wall field.
umping scenarios
a clear picture of
WMWA, it is not
possible to predict the interaction between the Third street
and WMWA walla or to adequately evaluate the rate and extent
of induced recharge from surface water bodies.
50. The WMWA stated that an additional off-site recovery well
should be constructed north of Third Street. This well will
allow a decrease in pumping from the Third Street Well
during heavy usage periods. The RP states it is unlikely
that replacing the Third Street recovery well with a well
400 to 500 feet further north (based on WMWA's suggested
location) that pumps 1 to 1.4 MGD would measurably change
the available yield in the WMWA well field. (See WMWA
Comment 4.)
WMWA believes an additional benefit of locating an
additional recovery well would be to minimize additional
ground-water contamination migration from east of the well
field. The contamination would normally have flowed
southeast, prior to being influenced by the flow lines of
the WMWA well-field cone of depression. WMWA also believes
while the Third Street well operates effectively as a
contaminant migration interference well, it greatly enlarges
the cone of depression of the WMWA well field, which would
potentially enhance contaminant migration from the east into
the well-field area. The RP disagrees with "replacing" the
Third Street Recovery well. The RP states that the amount
of water coming from the east to the well field, which is
beyond the contaminant plume, would not measurably change.
The RP states that numerical ground-water modeling will be
performed to better evaluate the effect of off-site pumping.
icenarioe for both the RP
are provided, and until a
recovery well cannot be evaluated*
t
EPA a'areea with WMWX'e pceition that the Third Street yell
can alter the source of water to wella in the well field.
without acre data and until an evaluation through Modeling
ia conducted. The future evaluation of the effectiveness of
17
-------
provide this input information.
51. The WMWA states that an assessment of the extent of the
contaminant migration around and into the WMWA well field is
not addressed in the HP's Risk Assessment or Remedial
Investigation Report. The WMWA data indicate that the 10
parts per billion (ppb) trichloroethylene (TCE) isopleth
extends west of Lycoming CreeJc toward WMWA Well 47, and on
the east and south toward WMWA wells 43,6,9 and 10. The
WMWA states that additional monitoring of the plume in and
around the WMWA well field during pumping and non-pumping
periods would provide an indication of off-site remedial
action as it relates to the well-field operations. (See WMWA
Comment 5).
The RP responds by stating that the effectiveness of the
ground-water program will be monitored by quarterly sampling
of existing monitoring wells as well as WMWA's water quality
sampling of their own wells. The RP questions how much
additional monitoring would be needed to demonstrate whether
or not ground-water quality is improving.
SPA believes that the need for additional grouadvater
monitoring cannot be rul«d out at this tiae baaed on the
data presented by the RP and WMWA. As Bore data become
available over tiae. *nd with the construction and
validation of a computer «o<3«l. the qroundifater development
and recovery scenario* will provide the information needed
to decide on additional Monitoring.
52. The WMWA states that the goal of the proposed plan should be
to restore the WMWA well field to its original water
"quality and quantity" potential without the need for the
WMWA to treat for VOCs. The WMWA comment states that an
interim goal during the remedial action period should be to
contain the contaminant plume in such a way as to avoid
impacting the WMWA pumping capacity as well as the need for
any additional treatment of VOCs, including off-gas or other
forms of additional VOC treatment by the WMWA. (See WMWA
Comment 6.)
The RP responded that the water quality in the WMWA well
field has already improved to levels generally below MCLs as
a result of the Third Street Recovery veil operation. In
addition, controlling the source of contaminants at the
Textron property boundary should result in cleanup of the
off-site ground water with the help of the Third Street
Recovery Well, such that this well can eventually be shut
down. The RP states that there is no indication that
recharge to the WMWA well field has been affected by the
Third Street Recovery Well.
13
-------
EPA acknowledges both the RP's and WMwy T ^«««enta. One
goal of the remedial action is to aininise off-site
migration of contaminants in ground vater flowing beneath
the AVCO Lvcomina site. The action will provide adequate
protection by controlling and reducing riafc through a
^rtmEH nation of cont*inmant. treatment, and inatitutional
controls. The action will contain and treat the
contaminated ground water on-site while the off-aite ground-
water plume is recovered ^n^ Created through the existing
ground-water treatment systea. with regard to the reduction
in recharge to the WMWA well field. BPA does not currently
have evidence that a reduction in recharge to the WMWA veil
field la occurring or may occur. According to the data and
available information, significant recharge occurs from
Lvcomina CreeX and the Susouehanna River.
19
-------
Source Docuaant: May 10, 1991 L«tt«r fro» BRM to U.S. SPA
32. The R? presented information to substantiate their rationale
for not conducting additional off-site ground-water recovery
at this tiae. provided: '
o "The present off-site risk to ground-water users is
within the acceptable range because the water from the
VMWA supply wells is treated. Only under hypothetical
situations of untreated ground-water use does any
unacceptable risk exist to potential users."
o "The limits of the overburden pluae are well-defined,
and the plume has been effectively contained by the
present remedial system. The plume is presently in a
steady state condition, and no further deterioration of
the aquifer is evident based on routine quarterly
monitoring over the past two to four years."
o "The on-site system will be expanded by implementing
the proposed remedy* This will increase the
contaminant mass removal on-site, block additional off-
site migration (both overburden and bedrock) and help
to improve the effectiveness of the off-site system."
o "The present off-site ground-water recovery system has
significantly reduced the concentrations in all of the
WMWA production wells, demonstrating the effectiveness
of the Third Street well as a blocking/recovery well.
As shown in the Remedial Investigation (RI), on-site
and off-site monitoring wells and the WMWA wells show
decreases in contaminant concentrations since
installation of the existing recovery systems."
o "The overburden plume is being captured by the pumping
of the Third Street Recovery Well. This was
demonstrated by a two-dimensional streamline model
completed by E£M. This model uses the same basic Theis
assumptions as the DREAMS or RESSQ models. The model
was used to demonstrate the capture area of the Third
Street Recovery Well when this veil is pumping at 500
GPM. In addition, each of the WMWA production wells
was simulated in the model to pump 100 GPM, and the
recharge boundary of Lycoming Creek was simulated using
the image veil theory to present a vorst-case scenario.
The model demonstrated that vhen pumping at the rate of
500 GPM, with all of the WMWA veils operating, the
Third Street Recovery Well effectively captures the
entire off-site overburden contaminant plume."
The RP further states that they "agree with the PADER that
it is prudent to operate the proposed on-site recovery
20
-------
system for a minimum of two years and a maximum of five
years to collect accurate operating data on the system."
These data will be used to determine the effectiveness of
the present off-site recovery system at reducing the off-
site plume mass. During this time period, a ground-water
flow and transport model will be calibrated, run, and
continually upgraded with site data to more reliably predict
cleanup times and the effectiveness of the off-site recovery
system. Based on these monitoring data and modeling
results, the need for additional off-site recovery will be
evaluated to determine whether additional off-site
remediation would be required and if so what the specific
requirements would be.
EPA agrees that tha •xistino and proposed aroundvater
short t«na, and is accepting th« rational* for not
finalizing tha decision on th« •act^nt off off-sit«
groundwatar r«cov«ry at this tia«. Hov«v«r. EPA will ba
evaluating th< mtf baaia of a future
Racord of Decision for OU-2.
21
-------
Source Document: Response to U.S. SPX and FADER Comments:
15 January 1991 Draft Remedial Investigation
Report for the Textron Lycoming Williamsport
Facility
54. The EPA requested that the RP discuss other potential
sources of contamination or provide that a review of all
other potential sources (through interviews and reviews of
file material from other hazardous waste generators in the
vicinity) have been identified. As noted during the site
visit, there was an odor which may have been a volatile
contaminant .
The RP stated that according to their interviews with plant
personnel and review of the Textron file material, no other
continuing sources to ground-water contamination were
identified. The RP stated that they do not have the
authority to obtain records from industries active in the
area to review operations and disposal practices. The RP
was not able to respond to the statement regarding the odors
noted during the site visit because they did not know where
in the study area the EPA noticed odors of volatile
organics .
EPA aareea that the RP did a thorough review of the
potential on-aite sources of the crroundvate
In response to obtaining information regarding hazardous
vaate generation and disposal practices of other Indus-tries,
that the source has been adequately characterised and no
further research is requested fro« the RP. with regard to
the source of the odors, it appears that the odors were
originating fro« outside of the AVCO Lycoaino: facility.
55. EPA requested that the RP provide modeling in the RI in
order to define the volume of soil to be remediated and the
length of time necessary for operation of the ground-water
treatment system. EPA noted that if this modeling would be
included in the FS or RA then the comment could be deleted.
The RP responded that the modeling is discussed in detail in
the responses to the draft Feasibility Study. The RP
reiterates that once the planned on-site remedial system is
installed and operating, data will be collected to check its
performance. The RP states that "After the system has been
operating as designed for two to three years, sufficient
data Would be available to initiate reliable modeling to
evaluate cleanup times. This would provide a better basis
to determine whether additional remedial measures are
warranted. "
22
-------
accaots tha deference to the modeling presentation in
the response to the Feasibility atudv comments. BPA doaa
not accept aa •valuation of tha system in tiro to three
years. The on-aite remedial svsten will be evaluated after
approximately tvo years operation. Baaed on this
evaluation, and additional studies, BPA will then evaluate
the effectiveness and develop plans for future off-site (00-
2) remediation.
56. EPA requested that the RP provide a detailed description of
the chemicals used at the site in order to perform a more
thorough characterization. EPA also requested that the RP
provide a list of compounds other than TCE which may have
been disposed of in the dry well. With regards to the
presence of semi-volatile compounds found in the outfall of
the Oliver Street storm sewer at concentrations above
background, EPA requested that the RP provide a list of all
chemicals associated with the plant to demonstrate that
there are or never have been semi-volatiles associated with
the plant.
The RP responded with a summary of the operations and
provided a list of chemicals presently used at the facility.
The RP also reiterated that during the RI, expanded chemical
analyses (Target Compound List and Target Analyte List) were
conducted on ground-water and soil samples. Based on these
data, the RP believes that the type of chemical compounds in
the environmental media in the study area have been
adequately characterized through the analytical work
completed and that no unknown compounds are present.
57. EPA expressed concern that the RP has not adequately
evaluated the ground-water contamination with regard to
separate phases, specifically Dense Non-Aqueous Phase
Liquids (DNAPLs). Consideration should be given to the
positioning of the screen intervals in order to best detect
DNAPLs. Trichloroethylene (TCE) has been observed to
increase with depth in the well nest containing MW-8, MW-
8D, and MW-62 which may be an indication of a DNAPL
contaainant source. The RP should provide an assessment of
the DNAPLs as they potentially reach and contaminate the
bedrock.
i
The RP provided evidence that consideration was given to
placement of the well screens in the overburden to evaluate
the potential for DNAPL. The RP has utilized a Kemmerer
sampler to obtain samples from the bottom of the wells and
no DNAPL was observed.
23
-------
53.
The RP states that the DNAPL may exist as a residual source
which is difficult to remediate and there is no current
technology available for this remediation. To date, the
cest available technology is to control the source.
The RP concluded that the data indicate that if a residual
source of TCE exists, it appears to be restricted to the on-
site area and feeds TCE to the ground water in a dissolved
phase. The data do not indicate that there is mobile DNAPL
and suggests that if non-aqueous phase liquids are present,
they are located on-site, most likely as an immobile
residual .
SPA agrees that th« data collected to <3at« indicate that the
DNAPL aa? not b« mobile. However, thera «ay ba DNAPL
residual sine* thara ara increasing concentrations of TCE
with 4«oth. Further •valuation of th« potential for and
occurrence of DNAPL will b« conducted during the design of
the on-sita recovery system.
EPA identified certain deficiencies in the RI and requested
that the RP provide tables, data, additional information, or
clarification. The topics are stated briefly below and
acknowledgement of EPA's receipt of requested information is
identified. The requested information was also made
available for public comment during the public comment
period for the Proposed Plan.
a)
b)
c)
d)
e)
f)
References in the RI.
to and accepted by
Correction on Section 3.8: Regional Hydrology.
Provided to and accepted bv SPA.
Section 3.9: Pages 3-17 and 3-18.
Section 4.6.1: Collection of Groundwater Samples
Provided nd acc^ttd b BPA.
Section 4.6.1.1: Field parameter collection.
i
Provided to and accepted bv SPA.
Section 4.6.4: Page 4-25; Use of immiscible interface
probe.
Provided to and acc»t«d
24
-------
g) Section 5.0: Consistency in labeling figures and
plates.
Provided to and accepted bv BPA.
h) Section 5.1.2.1: Past Plant Operations
Provided to and accepted by BPA. See response to
f?r»ma^nt 54 of this Responsiveness 8nB""arv.
i) Section 5.3.2.3: Page 5-17; Background soil data and
transcriptional errors.
Provided to and accepted by BPA.
j) Section 5.3.5: Comparison of laboratory VOC analysis to
Petrex Soil Gas Results
Provided to and accepted by BPA.
k) Section 5.4: Figure for overburden thickness isopachs.
Provided to and accepted by BPA.
1) Section 5.4: Inclusion of recovery wells on Plates 3,4,
and 5 and locations of potential areas of concern.
Provided to aad accepted by BPA.
m) Figure 5-32: Connect the hot spot around MW-3R to the
rest of the plume configuration.
Provided to and accepted by BPA.
n) Section 5.7.2.8: Estimate the total mass of
contaminants present in the saturated zone, both in the
liquid phase and sorbed to the solid phase.
Provided to and accepted by BPA.
o) Section 6, Page 6-2: Clarify the meaning of "low" in
the statement "overall VOC concentration in the soil
samples were low."
Provided to and accepted bv BPA.
p) Appendix 0: Remedial Investigation Quality
Assurance/Quality Control Review Report: Definition of
the "B" qualifier.
Provided to and accepted by BPA.
25
-------
33. FADER requested that the R? provide information regarding
the isolated occurrence of Arochlor-1254 (polychlorinated
biphenyl - i.e., ?C3) in soil boring SB-14B.
The RP provided information to substantiate that PC3s were
not used or disposed of at the site. The RP stated that the
soil sample was collected in conjunction with the
underground storage tank investigation being conducted in
cooperation with the PADER.
EPA acXaovladqaa the raaponae. In addition, BP* received
tha Underground 3torag« TanX raport ajd is currently
conducting a raviair and evaluation of tha document.
60. EPA questioned the unidentified.recharge boundary that
apparently exists 500 to 1,000 feet east of RW-2. EPA
requested information regarding regional geologic
information to support the apparent increase in the
thickness of the overburden east of the site.
The RP stated that the apparent recharge boundary is an
observation from the recovery test data discussed in the RI.
The RP stated that there is no known "regional geologic
data" to support the thickening of sediments east of RW-2,
but indicated that the site-specific data indicate
overburden thickness in this direction.
EPA acknowledges ind «cc«Pt» this response, .at this time.
f>
61. EPA requested that the RP provide information regarding the
potential for contaminants to migrate in the bedrock at Elm
Park and beneath Lycoming Creek. It appears that the water
level elevations at HW-60 and MW-32 appear to indicate an
upward hydraulic gradient but this is contradicted by the
fact that little if any of the overburden appears to be
saturated near the "bedrock ridge1* at Lycoming Creek. The
water level elevations in MW-14B and MW-72 indicate a
downward gradient. Presumably this reflects the impact of
pumping at the Ela Park recovery veil. Although operation
of this recovery veil might appear to affect Lycoming Creek
here, it is not clear that contaminants would also discharge
upvard given their apparent propensity to move southvest
along strike in the bedrock. EPA is concerned that the data
available regarding TCE-DCE concentrations in bedrock wells
provide little assurance that contaminants have not migrated
beneath Lycoming Creek.
The RP argues that there is a bedrock high in an area of
thicker saturated overburden sediments where MW-60 and MW-
32 are located. Therefore the upvard gradient at Elm Park
is an accurate observation of the hydrogeologic conditions.
26
-------
The RP indicates that it was not their intent to imply or
state in the Rl that all of the contaminants or ground water
in the bedrock at Elm Park discharge to the overburden
sediments.
EPA is not convinced that contaminants have not migrated
across Lvcomina Creek at Elm Park and will evaluate this
possibility with the second operable unit.
62. EPA requested that the RP provide further data
interpretation or analysis to explain the presence or
absence of vinyl chloride in the ground water from wells at
the perimeter of the plume. This information would provide
information relevant to the design of a ground-water
biorestoration remedial alternative.
The RP provided the hypothesis that the TCE to vinyl
chloride biodegradation is primarily through a reductive
dechlorination pathway, caused by anaerobic conditions
enhanced by the plant paving (approximately 85% is paved or
covered with buildings) . In addition, ethene can be the end
point from the abiotic degradation of the vinyl chloride.
The RP reviewed data from the wells at the perimeter of the
plume and concluded that the vinyl chloride concentrations
were below the detection limits of less than 1 ppb.
EPA notes and acknowledges the response. At this time the
hypothesis seeas plausible; however, additional aonitoring
for the degradation products of TCB will be substantive.
The science of biorestoration/bioremediation is still in its
infancy and information froa sites such as these will build
on the liaited existing <
63. EPA requested that the RP clarify the reason for the higher
pH in monitoring wells MW-64 and MW-66. EPA suggested that
these wells may need to be abandoned since they may be
grout-contaminated .
The RP responded that the reason for the high pH in these
wells is not clear. The RP indicated that they will
redevelop each of the wells with high pH and reevaluate the
integrity of the veils. The RP stated that pH is not a
factor affecting the concentration of the contaminant of
concern in the study area or the ability to detect these
compounds .
i
wells are needed. BPA disagrees that the oH will not
affect the ^bjljtv to detect the coapounda of interest. The
* (chlorinated hydrocarbons) are not directly
affected by elevated pH; the fact that the well aay not be
orooerly developed indicates that saaples collected from the
27
-------
va\T.3 aay not ba representative of tha aonitored aquifer.
64. ?ADER requested that the RP change the direction of the
arrows indicating ground-water flow in the bedrock so that
they are perpendicular to the ground-water contour lines.
The RP indicated that the flow conditions in the bedrock are
anisotropic, based on recovery test results. Therefore,
under anisotropic conditions, the direction of groundwater
flow is not necessarily perpendicular to the contours of the
pctentiometric surface as expected in isotropic flow
conditions. The RP stated that the direction of ground-
water flow, as depicted by the flow arrows are correct.
gPA acXnoirladqas and accepts th« r«3Dona«.
55. EPA stated that ground water appears to flow to the
Susquehanna River, which is about a mile south of the site;
however, no information could be found regarding a ground-
water discharge investigation. EPA suggested that the
discharge points be located and tested for any contamination
that might be entering the Susquehanna. This concern
revolves around the ultimate fate of the 1,1-
dichloroethylene as well as several metal contaminants
associated with the' site.
The RP indicated that ground-water flow from the overburden
beneath the Textron Lycoming facility should be captured by
the Third Street Recovery Well; and therefore, no discharge
to the Susquehanna River would occur. The RP also stated
that if contaminants were to discharge to the river from the
overburden aquifer, the contaminants would be diluted,
resulting in concentrations below detection limit. The RP
states that the bedrock aquifer in the vicinity of Third
Street does not contain contaminants of concern above the
analytical method detection limits.
v
w
should
be captured by the Third Street Recovery Well. However. as
stated in the 8ite Characteristics lection of the ROD, in
DCB concentrations of 37 pob and IS ppp« respectively.
do«s not *rl»t ia th< vicinity of Third 8tr««t. BPA
that th< ••t«la ar> attanuatad bv
aoil and may
not ti« of concern
At this tim«. tn« RP*« r<»pon»» ia
66. PADER requested information regarding the type of cooling
process used, especially with regard to the types of
chemicals used to treat the water.
28
-------
The RP responded that little is Icnown about the cooling
system, but it is believed to have been an air-water heat
exchanger in which air flows around coils containing water
which was not recirculated.
At thi3 time, the response ia adequate.
67. PADER requested that the RP clarify the reason for the
variation in detection limits used for vinyl chloride.
The RP stated that the analytical protocols used require
dilution of the samples where high concentrations of
contaminants are evident. TCE was the high concentration
contaminant that required the sample to be diluted. These
dilutions drive the final detection limits for all non-
detected compounds in the diluted analyses.
EPA acknowledges and accepts this response.
68. PADER requested information regarding an anomaly that the
concentrations of hexavalent chromium are greater than the
total chromium concentrations in wells MW-3 and MW-18.
The RP states that these two parameters are analyzed using
different methods, and the results for the two different
compounds in each well were below the permissible EPA error
range for laboratory analysis.
EPA notes and acknowledges this response.
69. EPA requested that the RP provide evidence and assurance
that chromium will not eventually migrate to the WMWA well
field. Based on data for MW-31, which is located south
(downgradient) of the old wastewater treatment plant, it
appears that off-site chromium migration is occurring. EPA
states that isoconcentration maps depicting chromium levels
should be included in the RI report. The EPA states that
the FS report should include remedial alternatives which
address the chromium as well as the organic contaminants.
The RP stated that there was no intention to de-emphasize
the occurrence of hexavalent chromium in the ground water
beneath the western portion of the plant. The primary focus
of the contaminants in the ground water are TCE, DCE, and
vinyl chloride. The RP states that the RI report indicated
that 'migration of hexavalent chromium beyond the plant
boundary is occurring. The RP provided an isoconcentration
map presenting the hexavalent chromium contaminant plume.
The RP states that effort was placed in the FS concerning
the remediation and treatment of the hexavalent chromium
portion of the contaminant plume. The RP conducts ongoing
29
-------
collection of samples and analyses for hexavalent and total
chroaiua.
At this tiaa 3PA doas not discount that remediation of the
3ourc« of the chromium gay b< naadad. Otherwise, BPA
acKnovladgaa and accapta this
The EPA stated that the Pennsylvania ARAR for ground water
for hazardous substances is that all ground water must be
remediated to "background" quality as specified by 25 Pa.
Cede §§264 .97 (i) , ( j) and 264 . 100 (a) (9) . The Commonwealth of
Pennsylvania also maintains that the requirement to
remediate to background is found in other legal authorities.
The RP does not agree that EPA should consider the
Pennsylvania ground-water "background standard" specified in
25 Pa. §§264.97(i) , (j) and 264. 100 (a) (9) to be an ARAR. The
RP argues that these standards are applicable to RCRA sites
not CERCLA sites. In addition, the standard is not relevant
and appropriate since it does not address problems or
situations sufficiently similar to those encountered at the
site and that their use is well suited to the site. The RP
argues that the RCRA standard is intended as a "prospective
detection and reaediation standard," and it is inappropriate
to apply such a standard to the situation at the Textron
Lycoaing facility where long-term historical contaaination
caused a ground water plume.
BPA disagree* that thi« r
-------
Source Document: Response to U.S. EPA and PADBR Comments:
31 January 1991 Draft Risk Assessment (RA)
Report for the Textron Lycoming Williamsport
Facility
71. In the RI review, EPA requested more information concerning
the impact of ground-water and soil contamination on
toxicity. The environmental risk assessment relating to the
contaminants vinyl chloride, 1, 1-dichloroethylene, and
hexavalent chromium should be addressed.
The RP stated that this is addressed in the response
comments on the draft Risk Assessment.
EPA notes and accepts this response.
72. EPA noted that it is the policy of the EPA to present a
conservative estimate of site risk as represented by
reasonable maximum exposure (RME) scenarios. This approach
may be explained as the highest exposure that is reasonably
expected to occur at a site. It includes consideration of
both exposure parameters and exposure point concentrations
for their relevance as reasonable maximums. EPA states that
the RP's RA report has presented a risk range rather than
calculating the RME.
The RP states that the RA report was prepared in accordance
with the interim final "Risk Assessment Guidance for
Superfund, volume 1, Human Health Evaluation Manual (EPA
540/1-89-002)." The carcinogenic risk for the RME scenario
equaled the reasonable risk scenario. Similarly, the hazard
for the RME was almost identical to the reasonable hazard.
Therefore, the RP requests approval to leave the
calculations as a range.
In addition, the RP noted that the RA guidance document
recommends the use of total unfiltered metals as a
conservative, worst-case approach to risk calculations. The
RP states that Region III has required full detection limits
in the calculation of averages for metals for other NPL
sites. The RP noted that all of the EPA recommendations
could b« included in the report, but the conclusions to the
RA and the media requiring remediation would remain the
same. Therefore, the RP requests EPA approval to leave the
calculations as reported in the RA.
acknowledges the re»pooif^ ^fld agrees that both
approaches conclude that siailar Media-specific remediation
is required.
31
-------
72. EPA noted that there vere transcriptional data errors in the
RA which should be corrected. in addition, the definitions
of exposure tiae (ET) , exposure frequency (EF) , and exposure
duration (ED) on page 5-16 do not coincide with the
calculations presented on page E-10 of the RA report.
The RP states that the ET, EF, and ED values on pages 5-16
and E-10 were given for different scenarios. the values on
page 5-16 reference VOC emissions from the air strippers
which were modeled to the nearest population, while the
values on page E-10 reference the inhalation of volatiles
from soil at source without modeling. Therefore, the
exposure values were different.
SPA acKnovlodcroa and accepts the response.
74. The EPA noted that the incorrect version of the "Risk
Assessment Guidance for Superfund Volume 1, Human Health
Evaluation Manual" was cited. The RA is to use the December
1989 version rather than the September 29, 1989 version.
The RP stated that the correct version was used in
preparation of the RA report.
SPA acknowledges and accepts the response.
75. EPA states that the risks were calculated using the
arithmetic mean of the constituent concentrations and
calculated again using the maximum concentrations.
According to the "Risk Assessment Guidance for Superfund
Volume 1, Human Health Evaluation Manual", the 95%
confidence interval of the arithmetic mean should be used
with other considerations to quantify the reasonable maximum
exposure (RME). The RME should be used in quantifying the
risks unless the deviations from the approach are approved
by EPA.
The RP noted that the modification was baaed on the
knowledge that ground-water risks calculated in the
preliminary risk assessment (ERM, 1988) exceeded EPA's
recommended carcinogenic risk range. The RP notes that the
ground-water data collected after submission has not shown
concentrations significantly different from the previous
levels. The RP requests EPA's approval for the deviation
based on the facts presented and the use of similar
conservative approaches on previous RA submittals made to
the agency.
BPA accepts the RP*> approach used to quantify site risks
based on the fact that « revaluation of the risks in
accordance with approved SPA aethodology would also result
in a Talue greater than 1 x 10 from the corresponding
32
-------
madia. Thus, bcth approaches conclude that similar media-
apecific remediation ia required, although in some instances
the ria* numfr^rs presented by the RPa are overly
conservative. The conservative nature of the PII»>S«T-«I
results from the use of several philosophical approaches to
the data that are inconsistent with EPA policy, including
the use of a riafc range rather than tha RMB. the use of
unfiltered natal3 data, and the use of full detection limits
for non-detect metals. BPA notes that the HP's request for
approval of this methodology, which ia based on tha fact
that similar conservative approaches have been used by tha
RP in prior submittals to the Agency, ia not a valid
argument for Agency acceptance.
76. The EPA noted that 11 of the 35 wells within the three-mile
radius of the site were identified as domestic water supply
wells. EPA requested that the RP provide justification for
not considering these wells as potential receptors. Ground-
water sampling data may be necessary to determine if these
wells have been impacted by the contaminant plume.
The RP stated that none of these wells are within the
defined plume boundaries, nor during the RI were any
migration pathways defined toward these wells.
EPA ackaovledaea the response and notes that in the future,
efforts shall be made to verify the existence of these
veils.
77. The EPA requested clarification of the statement that the
WMWA supplies five- to eight- percent of the water for
Williamsport. EPA is concerned whether this percentage is a
yearly average. EPA requested the seasonal percentages
rather than the yearly average.
The RP revised and submitted Table 2-2 which includes a
breakdown of the water usage from the two reservoirs and the
WMWA production well field during the months that the well
field was used.
78. EPA requested a text change for Section 2.5.1, Page 2-14 due
to inconsistencies between this report and the RI.
The HP submitted the revised page which was changed to be
consistent with the RI.
BPA acknowledges and accepts the response.
79. The EPA was concerned that the underground storage tanks may
be a contributing source due to elevated VOCs in the soil in
33
-------
the central section of the plant.
The RP noted that the Underground Storage Tank (UST) report
provides information regarding the soils investigation in
this area.
The 08T report has bean received by BPA and ia currently
being reviewed and evaluatad.
30. The EPA noted concern regarding the statements the "source
of the bedrock contamination is unclear" and "the primary
migration pathway for contaminants in the bedrock aquifer
corresponds to the primary ground-water flow direction."
The EPA is concerned with the migratory patterns of DNAPLs,
which do not necessarily follow the same flow paths as
ground water.
The RP stated that this comment has been addressed in the RI
response to EPA comments.
»A r»3Pons« to Conaant 57 of thia Responsiveness
31. EPA requested clarification of the conversion of the
reported chronic reference dose (RfD) to the subchronic RfD
listed in the Table for cadmium.
The RP removed the subchronic RfD for cadmium and noted that
the removal had no impact on the conclusions.
B7A acknowledges and acc«ot« the response.
32. EPA requested that the eleven scenarios be presented in
terms of current and future land uses. EPA indicates that
the data and/or calculations should be presented to
characterize the likelihood that exposures might actually
occur. EPA states that if it is unlikely that exposures
will occur, the scenario may be excluded from further
consideration provided there is sufficient justification
including review and comment from the EPA and PADER regional
project managers.
The RP requests that the changes in terminology from
"feasible" to "actual" and "hypothetical" to "future" not be
made in that the text, tables, and appendices would require
significant revisions. The RP requests that rather than
change the document, EPA should approve that an additional
page be inserted prior to the Executive Summary that defines
the terminology under the old (EPA, 1986) and final (EPA,
1989) guidance documents.
34
-------
acfcnoirl edges receipt of the page and accepts the
response.
35
-------
Source Document: Response to U.S. BPA and PXDBR Comments:
15 March 1991 Draft Feasibility study Report for
the Textron Lycoaing williamsport Facility
33. EPA questioned the lead concentrations in Appendix B of the
FS and stated that lead in soil should be remediated to less
than 200 parts per million (ppm) in residential areas.
The RP indicated that the maximum lead concentration
detected in site soils was 13.5 mg/kg; thus remediation of
the 'soil for lead is not required.
SPA notes and acknowledges this response. See additional
comment 112 of this Reaponaivene*** ?»"narv for details.
34. EPA suggested that additional remedial measures should be
considered in the FS for off-site ground water in the
vicinity of Elm Park. It is not adequate for the RP to
conclude that additional remedial measures are unnecessary
in the Elm Park Area, based on the statement that the Elm
Park well "is thought to intercept that portion of the
bedrock flow in the Tully member that is contaminated."
The RP states that remedial measures have been considered
but were not deemed necessary in the vicinity o-f Elm Park
for various reasons. The RP reiterated that the on-site
ground-water recovery system proposed in the FS should be
evaluated through data collection and evaluation after the
system is operational. The effectiveness of on-site and
off-site remediation will be evaluated two to three years
after start-up.
three veara. The off-tit* ground-water oluae irill be
treated as a separate operable unit and addreaaed by BPA in
a future ROD. See c 10 fl 51 of this
F"? for More detail.
35. EPA requested that the RP provide an estimate rather than an
assumed value of 30 years, using one of the three methods
provided in "Guidance on Remedial Actions for Contaminated
Groundwater at Superfund Sites'1 (EPA/540/G-88/003) to
determine the time frame for remediation of contaminated
ground water. EPA requested that the time frame for
restoration of both on-site and off-site ground water be
estimated.
i
The RP indicated that use of the 30-year time frame was for
the purpose of costing. The RP provided output from the
three methods as well as a slug transport model. The RP
indicated that since there appears to be a residual
contaminant source on-site, and because the mass of this
36
-------
source cannot be accurately determined, estimating cleanup
time for the on-site overburden and bedrock cannot be
defensibly performed at present. The continuous flushing
model and a slug transport model assumes that there will be
no migration of contaminants from the site once the on-site
recovery system is in place. The RP estimated the time for
remediation of the off-site overburden ground water, after
the installation of the system proposed in the FS, to range
from ten to 420 years.
This range is of a large magnitude because of the
uncertainty of the estimate. The RP states that "until the
apparent on-site source of contaminants is contained (the
goal of the recovery system proposed in the FS), and a trend
in the water quality response off-site is observed, an
accurate estimate of the cleanup time cannot be determined."
The RP reiterates that the progress of remediation on-site
and off-site is expected to require at least two to three
years due to the trend in water quality in response to the
remedial efforts undertaken to be observable.
The RP states that within the above range of remedy
duration, a reasonable estimate of cleanup time for the off-
site overburden ground water is 13 years with the operation
of the recovery system proposed in the FS. This estimate
assumes that the off-site plume will migrate as a slug to
the Third Street well at a retarded ground water velocity of
135 ft/day due to the partitioning of TCE between aquifer
materials and water.
EPA acknowledges receipt of the clean-up tin* estimates and
at this time accepts the RP*« response.
86. EPA indicated that perhaps the on-site clean-up times could
be shortened or enhanced by additional measures in the off-
site areas.
The RP does not believe that expanding off-site ground-
water recovery will enhance on-site ground-water recovery.
The reason for this is that remediating on-site ground water
via off-site recovery would require pulling ground-water
contaminants that have not yet left the site into an off-
site area of lover contamination. The RP believes that on-
site source control allows the remediation of off-site
ground-water by reducing contaminant loadings on the off-
site -aquifers.
i
At this time* BPA believes that expanding off-site ground-
recovery. However. SPA will consider allowing the on-site
system to be operational to provide information as to the
exact placement of additional off-site recovery veils is
37
-------
Bade.
37. PADER stated that the FS references the cleanup level as the
maximum contaminant level. Pennsylvania's position is that
all ground-water cleanups should be to background quality if
technically feasible.
The RP presented the same arguments regarding the validity
of the Pennsylvania requirements as an ARAR. See comments
23 and 71 of this Responsiveness Summary for further
information.
The RP believes that using the risk-based MCLs is a
reasonable approach. The RP does not believe that it is
feasible to reach background (or even MCLs) in a reasonable
time (less than 20 to 30 years) for sites with conditions
similar to Textron Lycoming's on-site aquifers, nor has it
been demonstrated.
EPA believes that background la the remediation cleanup
goal. B7A has selected the remedy in order to achieve this
requirement standard. At this ti»e BPA disagrees that this
requirement is not *a XRXR. and *t this tiae there la no
criterion. 8«« responses 127 and 170 of thia Reponslveneaa
for Bore details*
38. EPA and PADER expressed concern that it may be too early in
the remediation phase to determine air stripper tower sizes.
The size of the tower will be a function of the effluent
limits set by the facility's NPDES permit. Based on the
increased discharge volumes, a permit modification may will
be required.
The RP responded that preliminary sizing was conducted in
order to facilitate the cost estimation. The RP sized the
process equipment to conform to an assumed influent-effluent
basis, in the absence of final discharge limits from PAOER.
The FS notes that "effluent limitations will be determined
in coordination with PADER during the design phase.1*
EPA agrees that the specific tower siies will be determined
during the reaedial design phase.
89. The PADER noted that the proposed system of recovery wells
only stretches as far east as the area of MW-9 and MW-22.
These two wells are areas of high concentrations of TCE and
DCE. Any proposed recovery system must be aJble to prevent
contamination from leaving the site to the east of the area
of MW-9 and MW-22.
38
-------
The RP provided a revised figure illustrating the revised
location of the wells. The locations were changed to ensure
no migration from the eastern end of the plant will occur.
The RP provided an additional cost for this modification in
the three FS alternatives involving treatment. The RP
indicated that the final number of wells, spacing and
pumping rates may be modified to account for field
conditions. The RP noted that in addition to natural
variability within the overburden aquifer, well access for
drilling and subsurface utilities interference may influence
the final placement of the wells.
EPA accepts the revised spacing as response to this comment.
Hovevar. the proposed recovery system should ba designed to
3Jt«.
90. PADER states that the current off-site remediation is not
adequate as far as the complete ground-water resource is
concerned. PADER feels that additional recovery in the Elm
Park area is needed to increase the ongoing ground-water
cleanup efficiency. The PADER feels that interception of
the more significantly contaminated ground water within the
sand and gravel aquifer can be undertaken.
The RP agrees that additional remedial efforts should be
focused at the Textron facility. The contaminants migrating
beneath the plant are resupplying the mass to the existing
off-site plume, at a rate of approximately equal to the rate
of mass removal by off-site recovery wells. The RP believes
that the proposed on-site ground-water recovery system will
eliminate off-site migration of contaminants in the
overburden aquifers. Based on the overburden system modeled
by Chester Engineers, the former consultants, the Third
Street well could effectively contain the overburden plume
by pumping at a rate of 500 gpm. The well has pumped at
rates of 1,000 gpm in the past and is presently pumping at
650 gpm.
The RP states that there is no unacceptable risk to
municipal water users in the area and there are no other
known ground-water users in the area overlying the plume.
The RP indicates that adequate time will be needed to
properly evaluate the need for further off-site ground-
water recovery.
i
The RP developed and provided as an attachment, a
hypothetical off-site ground-water recovery option to assist
EPA and PADER in their consideration of the benefits of
installing additional off-site recovery versus the cost of
such measures. Two pumping wells and three injection wells
would be located approximately midway between the plant, the
39
-------
Elm Park recovery well, and the Third Street recovery well,
in the approximate center of the off-site plume. -Given the
location of the hypothetical system the RP estimates that i
could reduce the off-site remediation time by about a factor
of two. The RP states "however, additional off-site
recovery provides no additional reduction in risk or
protection of the WMWA well field compared to the existing
system." The estimated cost would result in an increase of
50% of the estimated cost over that for the on-site system.
The RP provided the revised cost as an attachment.
The RP estimates the time for cleanup, assuming the ground-
water remedial scenario presented in the FS , to be
approximately 13 years, based on the assumed slug transport
model. The RP indicated that the future evaluation of off-
site remedial alternatives to complement the existing off-
site recovery program can be performed once these data are
collected.
EPA is not only concerned with ris* reduction or protection
of the WMWA wall fitld but believes that remediation should
be conducted in the shortest tiae ffraae possible. BPA does
realise that there i» 4 need to evaluate the effectiveness
of the -on-site recover? »y3tm and the results of additional
studies prior to d+velopinq and improving the existing off-
site round-water rtcov^r s»t»«.
91. PADER requested that the RP change the wording on page 3-13
regarding State Acceptance.
The RP provided the corrected wording.
EPA accepts th< chano*.
92. The EPA requested clarification of the third and fourth
sentences on page 3-33: Administrative Feasibility.
The RP provided an explanation for these sentences by
explaining the reinjection step in Alternative GW-5.
EPA accepts the explanation
-------
Geothermal Fluid Release", Summers, K.S., Gherini and C.
Chen, Tetra Tech, Inc., (EPA/600/7-80-117, 1980) as modified
by EPA Region IV. Descriptions of the Summers model and NPL
sites where it has been applied are documented in
"Determining Soil Response Action Levels Based on Potential
Contaminant Migration to Ground Water: A Compendium of
Examples", EPA/540/2-89/057, EPA, 1989.
EPA notes that tha Bunnars model us«s th< linear equilibrium
relationship batvean the soil/vast* «nd th« leaching fluid.
EPA acknowledges and accepts th« r«3pona«.
94. PADER questioned the desirability of using fume incineration
for air-stripper off-gas controls.
The RP notes that two technologies, fume incineration and
vapor phase carbon, can be employed for control of air
stripper emissions. Vapor phase carbon alone is not an
appropriate technology for removal of vinyl chloride and
1,2-dichloroethylene. vinyl chloride and 1,2-
dichloroethylene are very poorly absorbed on vapor-phase
carbon and breaks through the carbon bed quickly.
Therefore, fume incineration is a much more appropriate
technology for the compounds of concern at Textron.
The RP notes that process control is much easier with fume
incineration for the constituents present in the off-gas.
This is because the fume incinerator operation can be linked
to the recovery system. This way, should the fume
incinerator fall below its design temperature range (as
determined during system design) for destroying the VOCs
present in the off-gas, no untreated air emissions will be
released. The RP concludes that fume incineration provides
efficient destruction of the vinyl chloride over the long
term, whereas vapor-phase carbon will not adsorb significant
quantities of vinyl chloride.
incinerator. How«v«r. th« ROD «p«cifi«« that this
information will b* conaid«r«d during th< •valuation for the
final dMion of th« r«m
-------
ri6_u .ric iU.T-T.2ry .-.-peri, prepared cv rer.r.sv_var.ia
Ie-ar~.T.er.~ cf £r.virtr.~er.~ al Resources (PACER),
«'«:~' ^ lr. ~~ °" ~ ~* • "
A<±nir.ist:ra-ive Record File available 4/15/91, update^
^- , ^i >*• / *•* ••
C / ^ C / 'i> i .
-------
REMEDIAL ENFCRCIMENT rlAMNIMG
1. Administrative Order cy Consent In the Matter of:
Avco Corporation site, 6/'2~/33. ?. 200001-20001".
2. letter to Ms. Beverly F. Doian, Textron, Inc., fro~
Mr. Stechen R. Wassersug, U.S. EPA, re: 104 (e)
request" for inforr.aticn, 7/17/33. ?. 200018-200026
A certified receiot is attached.
-------
"• ^ ~~ A J~."" ~ ~ ^ ™*^ MM .—• A /-< - a "
i-n •'Feas ib i lity Stuay wcrk plan by EPA,
ii_ letter frcm Environmental Resource
tne wor.< clan is attached.
Ls""~sr ~3 !'1r. Zucrsr.s 3sr.r.is U.S. Z?A frcn Mr. Lss
H. Trefsaer, Tsxircr. Lyccrr.ir.g, re: ERM's prepared
preli.~ir.ary responses fcr Textron Lycorr.ir.g 10 E?A's
ccr.r.er.ts rr. t'r.e P.I/FS wor< clar., 2/2/39. ?. 200011
Letter to Mr. Eugene Cer.r.is, U.S. EPA, from Mr.
Richard T. Wroblews
-------
9. Letter to Mr. Lee H, Trefsger, Textron Lvcoming,
from Mr. Eugene Dennis, U.S. EPA, re: Additional
comments on the RI/?S work plan, 6/13/39.
P. 200579-300551.
10. Report: Remedial Investigation Site Operations
Plan, crepared bv ERM, Inc., 7/12/89. P. 300532-
300623.
11. Letter to Mr. Lee H. Trefsger, Textron Lvcoming,
from,Mr. Eugene Dennis, U.S. EPA, re: EPA's
conditional acprcvai for the revised RI/FS work
plan, 7/25/39"." P. 300624-300624.
12. Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Larry S. Newcomer, PADER, re: Confirmation of
change of PADER project officers for the Textron
Lycoming site, 8/8/99. P. 300625-300626. A letter
to Mr. Lee Trefsger of Textron Lycoming concerning
the project officer change is attached.
13. Letter to'Mr. Eugene Dennis, U.S. EPA, from Mr.
Randy Farmerie, re: A completed review of the
second revision of the RI/FS work plan and the
Remedial Investigation. Site Operation Plan (RISOP),
8/15/89. P. 300627-300627.
14. Letter to Mr. Lee H. Trefsger, Textron Lycoming,
from Mr. Eugene Dennis, U.S. EPA, re: Final
approval of the revised RI/FS work plan, 8/15/89.
P. 300628-300628.
15. Report: Draft Remedial Investigation Report, Volume
I, prepared by ERM, Inc., 1/15/91. P. 300629-
300964K. A letter regarding the report is attached.
16. Report: Draft Remedial Investigation Report, Volume
II Appendices, prepared by by ERM, Inc., 1/15/91.
P. 300965-301863.
17. Report: Draft Remedial Investigation Report, Volume
III Appendices, prepared by ERM, Inc.,1/15/91.
•P. 301864-302539.
I
18. Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Randy Farmerie, PADER, re: Comments on the draft
Remedial Investigation report, 2/12/91. P. 302540-
302540.
-------
^ . . _~tter ~.~ Mr. _ee .rersger, .extron Lvcoming, rrom
:-'r. Eugene Zennis, U.S. EPA, re: Comments regarii:
the review of the draft Ris< Assessment reoort,
21. Letter to Mr. E u — e n e Zer. r. is/ *.S. ~ - A,
evera we
22. le""~er i^ Mr. Ise Tr05s^er Tex^rcn L,'/corr;r.G ^**^m
Mr. Euger.e Zer.r.is, U.S. EPA, re: Ccrr.ment:s on the
craf" Re.T.edial Ir.ves'igaticr. ar.d Risk Assessment cv
PACER, 2/7/31. ?. 302556-302553. A facsimile
" rar.srr. is s ion cover letter is attached.
22. P.eccrt: 3raft Ris< Assessment Report, prepared bv
Textron lycoming, 1/21/31. ?.' 2C2259-30312 1 . A
transmittal cover letter is attached.
24. Report: Draft Feasibility Study Report, prepared c\
Textron Lycoming, 3/15/91. P. 203122-303343*. A
transmittal cover letter is attached.
25. Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Randy Farmerie, PADER, re: Comments to the draft
Feasibility Study, 3/27/91. ?. 303349-303350.
26. Letter to Mr. Lee Trefsger, Textron Lycoming, from
Mr. Eugene Dennis, U.S. EPA, re: Comments from the
EPA on the draft Feasibility Study, 3/27/91.
P. 303351-303353.
27. Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Richard T. Wroblewsici and Mr. Charles Bandoian, ERM,
Inc., re: Transmittal of responses to comments on
the draft Remedial Investigation, Risk Assessment
,and Feasibility Study reports, 4/10/90. P. 303354-
'303419. The responses are attached.
29. U.S. EPA Proposed Plan, AVCO Lycoming Site, 4/91.
P. 303420-303435. A memorandum and corrected pages
are attached.
-------
29. Letter to Mr. Eugene Der.r.is, U.S. E?A, from Mr.
Richard T. Wrobiewski and Dr. Charles A. 3randoiar.,
Enviror.rr.er.tal Resources Management, Inc., re:
Further off-site ground water recovery, 5/1/91.
?. 202435-303446. A letter regarding comments on
the Proposed Plan is attached.
30. letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Richard T. Wrobiewski, Environmental Resources
Management, Inc., re: Textror./ERM (Environmental
Resources Management, Inc.) presentation to FADER
(Pennsylvania Department of Environmental
Resources)/EPA, 5/10/91. P. 303447-303451. A
summary of the Textror./ERM presentation is attached.
31. Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Richard T. Wrobiewski, Environmental Resources
Management, Inc., re: Correspondence to be
considered as comments on the Proposed Plan,
5/14/91. P. 303452-303453.
32. Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
James M. Luppert, Williamsport Municipal Water
Authority, re: Comments on the Proposed Plan,
5/14/91. P. 303454-303456.
33. Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Richard T. Wroblewski and Dr. Charles A. Bandoian,
Environmental Resources management, Inc., re:
Summary of Textron Lycoming's position regarding the
planned remedial action, 5/16/91. P. 303457-303459.
34. -Letter to Mr. Eugene Dennis, U.S. EPA, from Mr.
Richard T. Wroblewski and Dr. Charles A. Bandoian,
Environmental Resources Management, Inc., re:
Williamsport Municipal Water Authority's (WMWA)
comments on the Proposed Plan, 5/16/91. P. 303460-
303462.
35. Report: Independent Cost Estimate of Remedial
Action (CORA), 6/25/91.
36. Letter to Mr. Edwin B. Erickson, U.S. EPA, from Mr.
,A. Paul Franklin, PADER, re: State concurrence with
'the U.S. EPA's proposed remedy, 6/28/91.
-------
lues
-------
BIBLIOGRAPHY OF SITE SPECIFIC GUIDANCE DOCUMENTS
Risk Assessment Guidance for Superfur.d, Volume 1, Human
Health Evaluation Manual (Part A), Interim Final, prepared bv
U.S. I?A, 12/39.
EPA 540 1-39 002.
Ground-Water Protection Strategy, prepared by Office of
Ground-Water Protection, August 1, 1934.
EPA-440/6-34-002
Guidelines for Ground-Water Classification Under the
EPA Ground-water Protection Strategy, prepared by Office
of Ground-Water Protection, December 1, 1986.
CERCLA Corr.pliance with Other Environmental Statutes,
prepared by J.W. Porter, OSWER, October 2, 1935.
OSWER #9234.0-2
Attachments: Potentially Applicable or Relevant and
Appropriate Requirements
RCRA Ground-Water Monitoring Technical Enforcement Guidance
Document (T£CD~(Secondary^Reference),prepared
by EPA, September 1, 1986.
OSWER #9950.1
Final Guidance for the Coordination of ATSDR Health
Assessment Activities with the Superfund Remedial
Process, prepared by J.W. Porter, OSWER/OERR and ATSDR, May
14, 1987.
OSWER #9285.4-02
Attachment: Same Title, Dated 4/22/87.
-------
.e i - : .-. - r c cr.e , .-.rser.i_, -
ica- rrcri.es)
sees ccs, Bariu.r., Benzene,
er.z- < A; Pyrer.e, 3 = ±r.iu~, Career. Teirachlcr ide, Chlcrcber.zer.e,
er, C res els, Cyanide,
echar.e , 1 , 2-C ichlcrcechyler.e ; Volurr.e 29:
er.e, 1, 2-C ich lor ce chyle r.e, CIS-1, 2-
Hexacr.lorccer.zer.e, r.exacr.lcrcbucaciier.e ,
H e x a c rt 1 c r o c v c 1 c c e r*. ™ a ci i a r. e H e x a v a 1 e r. c C h r -T* ; u *"> "" ** o n ( a **. d
ccr.pcur.as), lead Lir.dar.e, Magar.ese (ar.d ccrr;pcur.ds ) , Mercury,
Mecr.vl Zir.'/l Keicr.e, rr.eir. vler. e Cr.lc-ride, N'accr.aler.e, N'ic^>.v \ . . . * . O y ^ - y_v..*~, ^- C — ^ . 4 *, «, * . I \ d * * ^* t— -™/
3yar..de, Sulfuric Acid, 2 , 2 , ^ , 5-Tet racr.lcrcdiber.zc-p-Dioxiri,
1, 1, 2 , 2-Tetrac." Icrcecr.ar.e, Tecrachloroechyler.e, Toluene,
1 , 1 , 2-7ncr.lcrce~r.ar.e, 1, 1, 1-Trichlorce'har.e
Tricr.lcrcetir.yler.e, 2 , 4 , 5-Tr ichlorophenol , 2,4,6-
Tricr.lorcpr.er.ol, Trivalent: Chromiun, Vinyl Chloride, Xylene,
Zinc (and ccr.pounds), prepared by ORD/OHEA/ZCAO and
GSWER/CE?.?., Septie.r.ber 1, 1934.
EPA- 5 4 0 / 1 - 3 6 / GO 1 -C 5 8
Integrated Risk Inf orma -ion Systems (IRIS) (A
Ccr.puter-3ased Risk Ir.f crrr.atiiGn Sysrem
Available Through E-Mail--3rochure on Access is
Included) , prepared by CKEA, (undated) .
HEAST Tables - Health Assessment Summary Tables.
Superfund Exposure Assessment Manual, prepared by OERR,
April 1, 1993.
OSWER #9285.5-1
Superfund Public Health Evaluation Manual, prepared by OERR
and OSWER, October 1, 1986.
OSWER #9285.4-1
•s, r
Endar.g.erment "Assessment Guidanae, (Secondary Reference) ,
prepared by. J:W. Porter, OSWER, November 22, 195.
OSWER #9850.0-1
ATSSR Tox*icity' Profiles, ATSDR/TP-88/xxx .
------- |