UniM SatM
Environmental
Agency
Office of
Emergency
EPA/ROO/R03-90/089
June 1990
AEPA
Superfund
Record of Decision;
Walsh Landfill, PA
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50272-101
REPORT DOCUMENTATION 11. REPORTHO. 12-
PAGE - EPA/ROD/R03-90/089
3. RKipienfe Accft8ion No.
4. TiUe and Subtitle
'UPERFUND RECORD OF DECISION
lalsh Landfill, PA
First Remedial Action
7. AUlhor(a)
5. Report Data
06/29/90
6.
a. P8rfonning Organization AeP'- No.
8. Performing Orgainization Name and Add-
10. ProjedlTuklWortt Unit No.
11. Contract(C) 01' Gnnt(G) No.
(C)
(G)
12. Sponaoring Organization Name and Addr888
U.S..Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
11 Type of Report . Period Cownd
800/000
14.
15. Supplementary Hotee
16. Abstract (Umit: 200 worda)
The 7-acre Walsh Landfill site encompasses an approximately 1.S-acre landfill and
surrounding area in a heavily wooded region of Honeybrook Township, Chester County,
Pennsylvania. The landfill reportedly received mixed municipal and industrial wastes
for disposal between 1963 and 1976; although State investigations in 1979 revealed
that disposal of hazardous waste at the site had resumed after that period.
Investigations by the State revealed the presence of fifteen to twenty drums
containing various hazardous substances, including VOCs. Fumes from the drums
reportedly sickened local residents, and organic and inorganic compounds were detected
in monitoring wells and private wells. In addition to waste disposal, open burning of
material was conducted in the southeastern portion of the landfill. Residential well
sampling from 1987 through 1989 resulted in an interim remedial measure in 1989 to
provide bottled water to 44 residences. Currently, the site is being operated as a
solid waste transfer station and salvage yard, and operations are increasing the
volume of landfill/junk yard debris, and the overall size of the site. This Re~ord of
Decision (ROD) addresses final source control for the landfill and allows for
expedited action on the contaminated drinking water supply. A second ROD will address
(See Attached Sheet)
17. Doewnent Analyala .. Deacrlptora
Record of Decision - Walsh Landfill, PA
First Remedial Action
Contaminated Media: soil, sediment, gw
Key Contaminants: VOCs (benzene, PCE, TCE),
lead)
b. IdentilieraJOpen-Ended Tenna
other organics (PAHs), metals (arsenic,
c. COSA 11 ReIdIGroup
AvailabiUty St8t8menI
11. Sec:wtty CIaM(Th18 AeporQ
None
20. Sec:wtty ClaM (ThI8 "'118)
Nnn):>
21. No. of P8088
80
I
22. Prl08
(See ~NSl-Z31.18)
SNIMInM:1i- on 118-
272 (4-77)
(FOI'IIWfty NTls.35)
Department of Co_08
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EPA/ROD/R03-90/089
Walsh Landfill, PA
First Remedial Action
>tract (Continued)
the contaminated ground water. The primary contaminants of
sediment, and ground water are VOCs including benzene, PCE,
including PARs; and metals including ar~~nic and lead.
concern affecting soil,
and TCE; other organics
The selected remedial action for this site includes removal of bulky items and debris
from the landfill surface for resource recovery, followed by construction of an
approximately 5.2-acre landfill cap; provision of an alternate water supply to
approximately 50 residences by extending the municipal water system; ground water
monitoring; and implementation of site access restrictions and institutiona~ controls,
including land use, ground water use, and deed restrictions. The estimated present
worth cost of this remedial action is ,$3,768,000, which includes an estimated annual O&M
cost of $63,090 for 25 years except years 5, 10, 15, 20, and 25 which will have an
estimated O&M cost of $108,950 due to the five-year reviews.
PERFORMANCE STANDARDS OR GOALS: Provision of an alternate water supply will ensure
availability of water meeting SDWA MCLs.
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RECORD OF DECISION
WALSH LANDFILL SUPERFUND SITE
(a.k.a. Welsh Road/Barkman Landfill Site)
DECLARATION
SITE NAME AND LOCATION
Walsh Landfill Site (a.k.a. Welsh Road/Barkman Landfill Site)
Chester County, Pennsylvania.
STATEMENT OF BASIS AND PURPOSE
This decision document presents the Remedial Action selected for
the first operable unit at the Walsh Landfill site. This action
provides for an alternate water supply and landfill cap to
address the primary risks posed by the site conditions. This
document was developed in accordance with the Comprehensive
Environmental Response, Compensation, and Liability Act of 1980,
as amended (CERCLA); and, to the extent practicable, the National
Contingency Plan (NCP), 40 CFR Part 300. The decisions contained
herein are based on information contained in the administrative
record for this site. A second Record of Decision (ROD) will be
prepared following the completion of the focused ground water and
feasibility study, and will address the contaminated ground water
aquifer at the site.
The Commonwealth of Pennsylvania. has concurred with the selection
of this remedy.
ASSESSMENT OF THE SITE
Pursuant to duly delegated authority, I hereby determine,
pursuant to section 106 of CERCLA, 42 U.S.C. section 9606, that
actual or threatened releases of hazardous substances from this
Site, as discussed in "Summary of site Risks," Section VII, if
not addres8ed by implementing the response action selected in
this Record of Decision, may present an imminent and substantial
endangerment to the public health, welfare, or the environment.
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DESCRIPTION OF THE REMEDY
EPA has selected, and the Commonwealth of Pennsylvania has
concurred on, the following Remedial Action for the first
operable unit at the Walsh Landfill Site. The remedial action
for this operable unit includes a final source control action for
the landfill and an alternate water supply. The second operable
unit will address the contaminated ground water aquifer. The
major components of the.Selected Remedial Action for the first
operable unit are as follows:
Selected Remedial Action: Alternative 4
* Construction of new water service lines, mains, hydrants,
and valves, and the connection to the Honey Brook Borough Water
Authority's water supply mains. It is estimated that 50 .
residences will be provided with this service, based on previous
sampling results, and the number of residents currently receiving
bottled water. The number and location of residences which will
receive public water will be verified during the design of this
remedial action.
*.Approximately 6500 feet of a-inch water main, 7500 feet of
4-inch and 3000 feet of 2-inch distribution lines will be
installed along PA State Route 10 and Welsh Road. Service lines
will be installed for each of the 50 households.
* The current water supply system will be upgraded to
provide sufficient capacity to service the impacted residences.
One water supply well will be installed and connected to the
Honey Brook Borough water supply system. A booster pump and
120,000-gallon water storage tank will also be required to
service the residents.
* Control of the new water lines and services will be
transferred to the Honey Brook Borough Water Authority as soon as
construction is completed.
* Resource recovery activities will be completed to remove
the bulky items and debris from the surface of the landfill in
order to prepare for construction of a landfill cap. Additional
information will be collected on the composition of the landfill
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materials during the design of a landfill cap. At a minimum, a
multi-media landfill cap that meets the requirements of the
Pennsylvania Municipal Solid Waste Regulations will be
constructed at the site. The cap will consist of a topsoil
component underlain by a soil layer, a drainage layer with a
permeability greater than a 1 x 10-3 em/sec., a high-density
polyethylene geomembrane, and a base soil layer over the
landfill. The cap will be designed to cover an area of at least
5.2 acres, and will be vegetated and sloped in accordance with
the state regulations. Surface water control measures will be
incorporated into the design of the landfill cap.
* Institutional controls including the construction of a
six-foot high fence topped with barbed or razor wire around the
perimeter of the landfill, and modification of the property deeds
for the landfill will be completed to restrict unauthorized use
or access to the site~ and to restrict future use and property
development.
STATUTORY DETERMINATIONS
The Selected Remedial Action (Alternative 4) is protective of
human health and the environment, complies with Federal and Stat'e
requirements that are legally applicable or relevant and
appropriate to the remedial action, and is cost-effective.
Connection to the public water supply and capping the landfill is
an effective remedy that will prevent human- exposure to the
contaminated media which are posing the primary risks at the
site: ground water and soils. This remedy utilizes permanent
solutions and alternate treatment technologies or resource
recovery technologies to the maximum extent practicable for this
site. However, because treatment of the principal threats at the
site was not found to be practicable, this remedy does not
satisfy the statutory preference for treatment as a principal
element. .
Because this remedy will leave ha~ardous.substances on-site, a
5-year review under Section 121(c) of CERCLA, 42 U.S.C. 9621(c),
.will be conducted for the Site to ensure that the remedy
continues to provide adequate protection of human health and the
environment.
J/ /
L- L-i. ,<- .
/ J / h-/
Da tie /
---
E ickson
Administrator
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I.
SITB NAME. LOCATION AND DESCRIPTIOH
The Walsh Landfill Site is located on approximately seven
acres, near the top of Welsh Mountain in Honeybrook Township,
Chester County, Pennsylvania (Figure 1-1). Approximately five-
sixths of the property area lies south of the Honeybrook
Township, Chester County line, while the remainder is located in
Caernarvon Township, Lancaster county. The entrance to the site
borders on Welsh Road, 200 feet east of the intersection of Welsh
Road with PA Route 10. The area surrounding the landfill is
heavily wooded, with agricultural activity situated approximately
one-half mile south of the site. Approximately 49 homes or
residential structures are situated within a half-mile radius
north,' east, and west of the landfill. Several residents live in
house trailers that are situated within five to ten feet of the
current salvage operation.
A salvage operation and waste transfer station are currently
operating on top of, and in the area surrounding the landfill.
The original landfill area covered approximately 1.5 acres on the
southern portion of the site. A large garage and mobile office
trailer are currently located near the main entrance to the
landfill, along Welsh Road. The surface of the landfill is
covered with assorted vehicles, dumpsters, appliances, tires,
batteries, empty underground storage 'tanks and drums,
construction waste and other debris. The southeastern portion of
the landfill was formerly used as a burn area, and currently two
patches of dead trees, and sparse vegetation exist along the
southern border. A stone/gravel access road exists along the
western and southern borders of the landfill property. A fifty-
foot power line/utility right-of-way also lies along the southern
border of the property. Areas to the north, east, and west are
woodlands interspersed with houses constructed on cleared lots.
The Walsh Landfill was constructed as a side-hill facility
in which the landfill materials were placed directly on the
existing ground surface near the ridge line of Welsh Mountain.
The axis of Welsh Mountain extends northeast to southwest, with
the mountain being the dominant topographic feature of the site
area. Surface runoff from the landfill generally flows' to the
south and southeast. Several spring-fed ponds in the Walsh
Landfill study area are situated to the south of the landfill,
and are drained by streams running south and southeast. These
streams drain into the West Branch of Brandywine Creek, which
eventually flows into the Delaware River.
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^^trO=~v^r./ ^
^^^==^-f(l'
~ LANDFILL
SITE
FIGURE I-I
WELSH ROAO/BARKMAN LANDFILL SITE
PROJECT LOCATION MAP
•OUUCCSt HOMIYMOOK.ML UHS. 7.S 70^0411 APNIC MAP, I9M, RfV. Ittl
MOMfANTOVII, ^A, U.S.t.1. TS TOPOfllA^NIC MAP. If St. MIV.
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II. SIT! HISTORY AND BNFORCEMENT ACTIVITIBS
The Walsh Landfill Site reportedly received mixed municipal
and industrial wastes for disposal between 1963 and 1976. The
site consists of several land parcels, bouqht at different times
by Grace and Ernest Barkman. Mr. Barkman operated a trash
haulinq business, "Ernest Barkman's Trash Disposal," and a
landfill on the property durinq this period. From 1970 up
throuqh the time of the reported landfill closure in 1976, Mr.
Barkman made several attempts to obtain state and Township
approval for a landfill at this location. Due to citizen
complaints reqardinq the site activities and continued non-
compliance with municipal solid waste requlations, as noted by
several inspections by state, county, and t~wnship officials, Mr.
Barkman's operation was never permitted.
Site inspections conducted by the Chester County Health
Department in 1970 described evidence of burninq automotive
materials and rebuildinq of a sewaqe collection truck on the
site. The Pennsylvania Department of Environmental Resources
(PADER) inspected the site various times from 1971 throuqh 1974
and issued several fines to Mr. Barkman for unacceptable landfill
practices and violation of the Pennsylvania Solid Waste
Manaqement Act. On July 31, 1973, criminal charqes were filed
aqainst Mr. Barkman by PADER, with respect to the unlawful
operation of a waste facility without a permit and for burninq of
solid waste at the site. Subsequent inspections of the site by
PADER in 1974 noted severalcontinuinq violations in the
landfill's operation. In addition, a formal objection was raised
by Honeybrook Township reqardinq the landfill's location in an
area zoned as farm-residence.
In January 1976, PADER noted that the landfill was
approachinq capacity, and requested that Mr-. Barkman submit a
final closure plan for the landfill in place of a permit
application for continued operation. PADER modified the closure
plan submitted by Mr. Barkman and approved it in December 1976.
PADER continued to inspect the site to monitor the closure
activities. The State inspection reports note several violations
of the penn.ylvania Solid Waste Manaqement Act and little
progress with landfill closure.
In the summer of 1979, PADER received complaints from local
citizens reqardinq the dumpinq of suspected hazardous materials
at the site. The State investiqated this complaint and visited
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the site on July 7, 1979 to find that waste disposal activities
had resumed. Numerous drums were found on the site with labels
describing their contents and source as sludge residue from
roofing tars and Calcozine from Sunoco Products in Downingtown,
PA. PADER also observed evidence of leakage from 20 full 55-
gallon drums onto an adjacent residential property. Information
obtained from the drum labels described the contents and source
as Ridoline 442 (corrosive) and various acids from Penguin
Industries in coatesville, PA.
In conjunction with the above findings, PADER receiv~d a
complaint that fumes emanating from. the drums had sickened local
residents. The state and Chester county Health Department
proceeded to sample private wells in the area and found elevated
levels of organic and inorganic compounds. Also, in accordance
with the landfill closure plan, four onsite monitoring wells were
installed, sampled, and found to contain organic and inorganic
contamination. PADER and Chester County continued to receive
citizen complaints during 1980 and 1981 regarding noticeable
odors and a foul taste of their well water, and sampling results
continued to show elevated levels of contaminants in the wells..
During a March 1981 site inspection, 15 to 20 full 55-gallon
drums were noted onsite, and open burning of other material was
occurring. The State advised Mr. Barkman of proper handling
procedures, but a fOllow-up inspection in May 1981 showed the
drums remained onsite. .
On September 2, 1982, a 60-day notice of intent to file a
citizen suit in accordance with the Pennsylvania Clean streams
Law was issued to Mr. Barkman for improper operation,
maintenance, and construction of a landfill which rendered water
in nearby wells unfit for consumption. In February 198_3, Mr.
Barkman's consultant, Nassaux-Hemsley, Incorporated, proposed
that the dumping of liquids used-to clean out dairy tanks at
three sites in close proximity to the landfill were partially
responsible for the ground water contamination.
In April 1983, a fuel oil spill occurred at the site when a
heating oil tanker leaked and oil pooled on the landfill surface.
EPA and PADER's files indicate that twelve drums of fuel oil were
collected by Mr. Barkman and shipped to what Mr. Barkman termed
his "other location,. and 25 cubic yards of soil were removed and
taken to Lanchester Landfill for disposal. In addition, one full
55-gallon drum, labelled "ARCb Polymers, D-3, SHEREX Chemical
Company, Dublin, Ohio. was. found on the landfill.
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In December 1983, DER prepared a draft order to be issued to
Mr. Barkman for voluntary closure of the lanafill ana the
elimination of soil and ground water pollution by May 1984. This
draft order was never finalized due to the placement of the site
on EPA's National Priorities List in September 1984.
Prior to the NPL listing, in June 1984,EPA sampled several
55-gallon drums found on Mr. Barkman's landfill. The drums
contained various hazardous substances including: toluene,
ethylbenzene, 1,1-dichloropropane, chlorobenzene and methylene
chloride. EPA issued a unilateral order to Mr. Barkman on
February 22, 1985, directing him to complete the containment and
removal of these drums to a permitted disposal facility. Mr.
Barkman initially agreed to complete this work, but later proved
uncooperative, and EPA completed the work using Federal funds.
In 1985, PADER became the lead agency for the Walsh Landfill
Site, and entered into a cooperative agreement with EPA to
conduct a Remedial Investigation and Feasibility Study (RI/FS).
The site was classified as a state-lead-Superfund site, and- PADER
proceeded to hire a contractor, SMC Martin, to perform the
required site investigation work.
In the fall of 1985, EPA issued correspondence requesting
information from five companies whose labelled drums had been
found on the site. The five companies included: Penquin
Industries, Inc. of Coatesville, PA: Schick Electric, Inc. of
Lancaster, PA: Sperry New Holland of New Holland, PA: Sonoco
Products of Downingtown, PA: and, Sherex Chemical Company of
Dublin, Ohio. EPA received responses from these companies
indicating that they had no information and/or knowledge
regarding the disposal of hazardous materials or drummed wastes
at the Walsh Landfill site. Thus Mr. Barkman, the site owner was
the only responsible party who received a notice letter for the
RI/FS work: Mr. Barkman received notice from PADER in January
1985 and April 1986, and from EPA on May 31, 1989. Mr. Barkman
did not volunteer to complete or fund the required work for the
site. .
The RI field studies were initiated in 1987 and the final RI
report was .ubmitted by PADER's consultant in 1988. PADER
conducted ..veral rounds of residential well sampling in 1987,
1988, and 1989. Based on the results of this sampling, PADER
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6
issued an advisory to local residents in March 1989 and began
supplying bottled water to 44 residential units, or structures.
The provision of bottled water constituted an interim remedial
measure, and the action was taken in order to be protective of
public health~ Low levels of primarily organic contaminants were
detected at random intervals .and various well locations among the
49 residential structures in the Site area. In addition, little
documented information was available on the health effects of
exposure to the detected contaminants. Due to these
uncertainties, the provision of bottled water was selected as a
protective measure for the residents who use ground water as
their domestic water supply. "
The Site is currently operated as a solid waste transfer
station and salvage yard. Access to the Site is unsecured, and
the continuing operations are contributing to the increased
volume of landfill/junkyard debris, and the overall size of the
Site.
III. COMMUNITY PARTICIPATIOK
-
-
In accordance with Sections l13(k)(2) and 117 of CERCLA, on
March 18, 1990, EPA placed a quarter page advertisement in the
West. Chester Daily Local and the Lancaster New Era, announcing
the JO-day comment period on the Proposed Plan for the first -
operable unit of the Walsh Landfill Site. Also announced was the
availability of the Proposed Plan, RI/FS, and Public Health
Evaluation reports, as part of the Administrative
Record in the site information repository: Honey Brook Public
Library.
The public comment period began March 18, 1990, and ended
Hay 18, 1990. EPA received a timely request for an extension of
the comment period, and thus granted the minimum JO-day
extension, in accordance with the revised provisions of the NCP.
A public meeting was conducted on March 27, 1990 in order to
facilitate receiving the public's comments and concerns with the
proposed action for the first operable unit at the site. The
local citizens who attended the meeting appeared to generally
agree with the proposed remedial action for the contaminated"
drinking water supply and the landfill. Specific comments and
concerns raised by the local community are addressed in the
Responsiveness Summary.
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IV.
SCOPB AND ROLE OP OPERABLE UNIT
The Walsh Landfill Site has been divided into two operable
units (OUs), or site components, in order to effectively address
the complex contamination problems present in the various
environmental media. The institutional and containment actions
included in the remedy for the first au will address the
principal threats to human health posed by the presence of
elevated levels of organic and inorganic contaminants in private
wells and landfill soils. au number one allows for expedited
action on the contaminated drinking water supply and final source
control action for the landfill. au number two will consist of
the remedy selection for contaminated ground water. This
approach to remediation will allow for expedited action to
address health threats while further study of ground water clean-
up alternatives is completed.
The remedy for au number one removes the threats to public
health posed by the ingestion and/or inhalation of contaminated
ground water by extending a municipal water line to service the
affected residents in the area of the site. The remedy also
addresses the threats to public health posed by the ingestion of,
inhalation of, and dermal contact with contaminated landfill
soils by placing a cap over the landfill and fencing the area.
The landfill cap will address the threat to the environment by
substantially reducing the amount of percolation throug~ the
landfill, and thus the amount of leachate entering the ground
water.
The remedial action for the first operable unit also will
address the local community's concerns with Mr. Barkman's current
operations. The locai citizens are concerned with the open
burning practices and miscellaneous waste handling activities
that are reported to occur at the site, and any health or
environmental risks that these may pose. Capping the landfill
will necessitate ceasing the current operations on Mr. Barkman's
property, and will require the removal and decontamination of the
salvage materials and waste products currently placed on the
site. . .
The r...dial actions included in the first au will address
the primary human health threats posed by Site conditions. The
remedy for the first OU will allow for the primary health
risks to be addressed while the investigation required for the
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second OU, the contaminated ground water aquifer, proceeds. A
limited study of the site's ground water flow dynamics and
chemical characteristics will be completed in order to develop
information on effective cleanup remedies for the aquifer, as the
second OU for the site.
v.
SUXMARY OP SITS CHARACTERISTICS
BDvironmen~al Se~~ina and Clima~.
C~ester and Lancaster Counties, which encompass the~alsh
Landfill Site, are located in Southeastern Pennsylvania. This
area lies within the Piedmont physiographic province of the
Appalachian Highlands. The province is bounded on the west by
the Blue Ridge province, and to the east by the Coastal Plain.
The topography of the site is dominated by Welsh Mountain, which
extends northeast to southwest.
The climate in the area is mild, humid, with well-defined
seasons. Temperatures are usually moderate. precipitation i.s
generally ample and dependable, with the greatest amount falling
during summer months. The prevalent wind direction is from the.
west with an average speed of 9.5 miles per hour.
1. Reaional Geoloav
Bedrock underlyin~ the Walsh Landfill Site is characterized
by two distinct, highly fractured .geologic units. The oldest of
these is a Precambrian-aged amphibolite and granulite facies
felsic gneiss and graphite-bearing felsic gneiss. This unit is
located just to the south of the landfill.
The second unit is the Hellam conglomerate member of the
Cambrian Chickies Quartzite Formation. This unit, which forms
the ridge-cap of Welsh Mountain, is located directly beneath the
landfill and consists of a fractured, white, tan or gray to blue-
gray conglo8erate with occasional interbedded green, fine-grained
quartzite, occasional iron staining, and occasional thin shaley
layers. .
The contact between the~ Precambrian gneiss and the Cambrian
quartzite i. characterized by. a heavily fractured and weathered
zone approximately three feet in thickness. The Cambrian-
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Precambrian contact is located approximately 300 to 350 feet
south of the southern border of the landfill and strikes N69
degrees E. The dip of the contact is believed to be bet~een 40
degrees and 53 degrees to the northwest. .
The bedrock is generally overlain by saprolite. Saprolite
is defined as a soft, variably to thoroughly decomposed rock
formed in place by chemical weathering of igneous or metamorphic
rocks. Both the Precambrian gneiss and the Chickies quartzite
have associated saprolite layers. This overburden material
ranges in thickness from approximately 10 to 40 feet beneath the
Walsh Landfill to over 90 feet in the vicinity of the Cambrian -
Precambrian contact.
2. Hvdroaeoloay
Ground water in the vicinity of the Walsh Landfill Site
occurs in a fractured bedrock aquifer under confined to semi-
confined conditions. The ground water in the landfill area is
encountered in the quartzitic and gneissic bedrock and in the
saprolitic overburden. Both of these systems apparently are
interconnected and are flowing in a general south-southeasterly
direction fOllowing the surface topography. The bedrock is a
fractured medium and, therefore, ground water migrates mostly
along avenues of secondary porosity, such as interconnected
bedrock fractures. Ground water flow through the interconnected
fractures can be rapid compared to that in the surrounding
bedrock material, and the direction locally may vary
substantially from the average gradient.
Ground water flow is controlled by the geometry,
orientation, and interconnections within the bedrock fractures.
These properties are quite variable, and thus a complex flow
field has developed at the site. In general, the ground water
appears to be flowing from the northwest to the southeast.
However, due to the fractured nature of the bedrock, and induced
stresses on the aquifer due to the .pumping of residential wells,
the actual direction of ground water flow may vary a great deal
from the direction of the average gradient. These variations may
induce local ground water flow and contaminant migration to occur
in any direction. Contaminant migration will also be influenced
by dispersive processes acting within the aquifer.
The fractured bedrock aquifer currently is the primary
source of water in the site vicinity: most residents use ground
water as a source of potable water for their homes and farms.
I
J
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Due to the detection of organic contaminants in several
residential wells in the area, PADER initially provided bottled
drinking water to 44 residential structures beginning in March
1989. The number of residential structures receiving bottled
water has varied over the past two years. The primary reasons
for such variation have been independent sampling completed by
residents, and families moving in and out of the area. Many
residents continue to use ground water for other activities such
as bathing and washing.
3.
Jlv4roloav
Soils in the site area are generally the silt loams typical
of the Neshaminy-Glenelg and Edgemont Associations.. The soils at
the site are a mixture of native soils, demolition and
construction debris, and various plastics, paper, and metal
debris. The landfill area drains south and southeast by surface
runoff. Several spring-fed ponds situated to the south of the
landfill are drained by streams running south and southeast. The
surface water from the landfill drains into the West Branch of
Brandywine Creek, which flows into the Delaware River.
VI.
n'l'URB AND Brl'BNT 01' COH'l'AMINATIOIf
The primary risks attributed to the previous disposal
practices at the Walsh Landfill site are the degradation of the
ground water quality (specifically, the potable drinking water
supply), and soils contamination. Surface soils and sediments at
the site have elevated levels of polynuclear aromatic
hydrocarbons (P~s) and metals including arsenic, cadmium, lead
and nickel. The ground water system, including the potable water
supply, contains volatile organic contaminants including 1,1-
dichloroethane, chloroform, benzene, trichloroethylene,
tetrachloroethylene, and the metals arsenic, cadmium, lead and
mercury.
All sampling completed during the field studies indicated
the landfill as the source of contamination. No sampling of the
landfill materials was completed to characterize the composition
of the waste materials in the landfill, or to identify zones or
pockets of concentrated contamination. The data identifies
localized areas of soil contamination, and sporadic occasions of
ground water contamination offering no clearly defined or
predictable contaminant plume.
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The routes of exposure to the contaminants present at the
site include: ingestion and inhalation of ground water; and
ingestion of, inhalation of, and dermal contact with landfill
soils by local residents and landfill workers. At present, 44
residential structures are receiving bottled drinking water from
PADER. These residents continue to use ground water for bathing
and washing, and thus remain at risk from inhalation of volatiles
in their homes.
The ongoing activities at the landfill involve heavy vehicle
traffic during the solid waste transfer and salvage operations.
This activity may pose a potential risk to local residents by
generating dust from the landfill soils and sediments, and
creating a possible mechanism for an airborne release of
contaminants. In addition, the unsecured status of the southern,
eastern and western edges of the landfill/junkyard may allow
local residents to come into direct contact with the inorganic
contaminants and PAHs detected in landfill soils. Access to the
site may also pose a general safety hazard to local residents due
to the placement of various unstable piles of salvage materials,
vehicles, and construction debris on the sloped areas around the
site perimeter.
A. Remedial IDvestiaatioD (RI)
The RI field activities and analytical program were designed
to define the extent of environmental contamination from the
landfill, to identify migration pathways, and to provide data to
support a feasibility study of potential remedial actions. In
1985, PADER retained the services of SMC Martin Incorporated, of
Valley Forge, PA to conduct the RI/FS for the Walsh Landfill
site.
The scope of SMC Martin's RI included: surface water and
sediment sampling, surface and subsurface soil sampling;
monitoring well construction, testing, and sampling; residential
well sampling; limited air quality sampling, and preparation of a
report summarizing the results of the field and analytical
program.
The following figures are provided to illustrate the scope
of the field prograa:
Figure
Figure
Figure
Figure
1 - Surface Soil Sampling Locations;
2 - Surface Water' Sediment Sampling Locations;
3 - Monitoring Wells/Sampling Locations; and
4 - Residential Wells/Sampling Locations.
-------
figure 1
WELSH ROAD/BARKMAN LANDFILL SITE
COMPOSITE SURFACE SOIL SAMPLING LOCATION
MODIFIED FROM SMC (1988)
SS-B COMPOSHf SUHTACt SOU
• SAUPltNC IOCAnow
NOtTS: ONC. no AMD TMRtt fOOl
MltNVAlS WfWf COHPO9ICD MTO ONE
SAMPlt AT EACH SAUPIINC IOC*HOW
SS-I WAS TAKCN TOO rtCT 1*51 Of
-------
Figure 2
WELSH ROAD/BAH AN LANDFILL SITE
SURFACE WATER AND SEDIMENT SAMPLING LOCATION
MODIFIED FKOM SMC (IMS)
sw-?
• SCD-2
EXPLANATION
SUKTACC WATCH AND SCDMCNT
SAMPLING IOCAIION
NOTE: SEDIMENT SAUPU Al S«-< IOCAHQN
IS KKNItCAl TO COUPOSIIT SOU
SAUPtE TAKCN AT THIS LOCATKM
(SS-15)
SCAIE
WO
1000
-------
Figure)
WELSH ROAD/BARKMAN LANDFILL SITE
MONITORING WELL SAM FLING LOCATIONS
MODIFIED FROM SMC (1988)
.OCR-3
BEDROCK MOMTORMC NCU LOCATION
(IN51ALUD BY SilC MARITN INC.)
SHALLOW OVCR8URDEN «CU LOCATION
(INSTALLED BY SUC MARTIN INC )
CORtHOLE LOCATION
BCOROCK UOMTORtNC «
-------
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WELSH ROAD/8AR~ .AN LANDFILLSITE
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MODIFIED FROM 8MC (1988)
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-------
16
In July 1989, PACER contracted with Baker/TSA, Incorporated
of Coraopolis, PA to complete the feasibility study, a ground
water summary report, and the public health evaluation required
~s part of the RI/FS for the Walsh Landfill Site. Baker used the
results of the RI conducted by SMC Martin in order to complete
the Feasibility Study (FS) and public health evaluation.
B. 8ummarv of RI Pind~
A summary of the results from the RI sampling program
conducted by SMC Martin is presented below.
80ils
a) Elevated concentrations of arsenic (17 ppm), chromium (86
ppm), copper (43 ppm), lead (115 ppm), and zinc (616 ppm)
were detected in the composite soil samples collected from
the southern portion of the landfill.
b) Sampling locations SS-4, SS-8, SS-12, and SS-15 OPT
showed elevated levels (390-6000 ppb) of several
contaminants that are classified as coal tar derivatives
(acenaphthylene, phenanthrene, fluoranthene, pyrene,
chyrsene, benzo(b)fluoranthene, benzo(k)fluoranthene, and
benzo(a)pyrene).
c) Subsurface soil samples collected during well
construction activities showed elevated levels of bis(2-
ethylhexyl)phthalate (1300 ppb) at location SMW-4-SS.
Monitorina Well 8amDlinq
a) Results from two rounds of monitoring well sampling
showed elevated levels of trichloroethane, chloroethane,
toluene and total xylenes (5-35 ppb range) in wells MW-1,
MW-3, MW-4, MW-4, MW-S, and MW-6.
b) Bis(2-ethylhexyl)phthalate was detected at elevated
levels (20-72 ppb) in samples from MW-4, MW-5, and MW-6.
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17
c) Arsenic (34 ppb), barium (703 ppb), cadmium (20.2 ppb),
chromium (48.7 ppb), lead (16ppb), mercury (2.1 ppb), and
zinc (427 ppb) were elevated -in samples from several site
monitoring wells. The metals aluminum, iron, magnesium,
potassium, and sodium were also elevated in samples from
several wells (MW-3, SMW-4, MW-4, MW-5).
Residential .ell S&mDlinq
a) Results from two rounds of residential well sampling
showed elevated levels of carbon disulfide, l,l-dichlo-
roethane, chloroform, 2-butanone, l,l,l-trichloroethane,
bromodichloromethane, benzene, toluene, ethylbenzene and
total xylenes (5-87 ppb range). These contaminants were
detected in wells situated to the east and west of the
landfill area.
b) Di-n-butylphthalate and bis(2-ethylhexyl) phthalate
were detected at levels ranging from 11-150 ppb in several
residences near the landfill.
c) High levels of iron (129,200 ppb), magnesium (11,050
ppb), and manganese (7,340 ppb) were detected at locations
RES-l7, RES-18, RES-23, and RES-26.
d) Barium (214 ppb), cadmium, chromium (19 ppbt, cobalt
(51 ppb), copper (233 ppb), lead (24.5 ppb), mercury (8.2
ppb), zinc (321 ppb), and phenols (24 ppb) were detected at
elevated levels in numerous residences near the landfill.
Mx
a) Results of the air quality surveillance showed elevated
concentrations of chloroform (0.14 mg/m ) and hydrogen
chloride (4.1 mg/m ) along the western perimeter of the
site. These levels were detected in only one of three
sampling episodes. It is assumed that these contaminants
were detected from the current site operation and junkyard
activities since the landfill was reportedly closed by 1976.
Table. A, B, and C summarize the maximum, minimum and
average concentrations of the constituents of concern for the
soils, sediments and surface water, and ground water at the site.
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18
TABLE A
WELSH ROAD/BARKMAN LANDFILL SITE
SUMMARY STATISTICS FOR SURFACE S_OIL AND SEDIMENT SAMPLES
CONCENTRATION (~g/kg)
Constituent Frequency
Maximum Minimum Mean
Surface Soil
Chloroform 6.00 6.00 3.28 1/20
PAHs 1.1 x 103 3.9 x 102 2.6B x 102 4120
Arsenic 1.7xL04 6.1xl03 9.49 x 103 15/18
Cadmium 1. 16 x 104 1.70 x 103 3.01 x 103 8/18
Lead 1.15x105 3.8 x 103 1.69 x 104 17/1B
Nickel 5.50 x 1()4 5.50 x 103 1.37 x 10" 17/18
Sediment
PAH, 6.7 x 102 6.7 x 102 4.79 x 102 1/4
Cadmium 8.7 x 1()3 7.10 x 1()3 4.43 x 103 2/4
Lead 2.2 x 1()4 2.2 x 1()4 4.32 x 103 1/4
Nickel 4.3 x 1()4 8.7 x 1()3 2.09 x 1()4 414
..
TABLES
WELSH ROAD/BARKMAN LANDFILL SITE
. SUMMARY STATISTICS FOR SURFACE WATER SAMPLES
CONCENTRATION (pg/1)
. Constituent Frequency
Maximum Minimum Mean
Arsenic 12.20 12.20 5.98 1/5
Cadmium 3.80 3.80 2.72 1/5
Lead 10.10 9.30 4.30 2/5
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19
TABLE C
WELSH ROAD/BARKMAN LANDFILL SITE
SUMMARY STATISTICS FOR GROUNDWATER SAMPLES
CONCENTRATION (~g/1)
Constituent Frequency
Maximum Minimum Mean
1,1- Oichloroethane 9.00 1.00 1.82 12/113
Chloroform 87.00 8.00 2.82 7/113
Benzene 7.00 1.00 1.84 15/113
Ethylbenzene 24.00 1.00 1.73 14/113
Xylenes (Total) 35.00 2.00 1.96 12/113
T richloroethy lene 20.00 1.00 1.80 22/113
Tetrachloroethylene 3.00 1.00 2.03 16/113
Arsenic 34.00 8.30 2.62 5/116
Cadmium 24.00 2.30 2.18 14/116
Lead 106.00 2.60 2.84 43/116
Mercury 8.20 0.11 0.05 31/116
Nickel 111.00 5.30 11.80 161116
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20
C. CODclusioDS from the RI
The data collected during the RI do not identify anyone
specific source area of contamination, other than the landfill as
a whole. In general, the RI identified localized areas of
contamination in both soils and ground water. Elevated
levels of contaminants were detected in surface soils, sediment
and surface water on top of, downgradient from, and adjacent to
the landfill: levels of contaminants decreased with greater
distance from the site. .
Ground water contamination also appeared to be present in
certain localized areas, with only one area identified as a
potential plume migrating from the landfill. This area extends
approximately 600 feet south of the landfill property, and the
characteristic contaminants include: toluene, ethylbenzene,
xylene, trichloroethylene, and l,l-dichloroethane. The RI data,
however, did not reveal a well defined plume~
Residential well sampling completed prior to, and during the
RI provided water chemistry information on 49 residences situated
adjacent to the site. Results of this sampling showed that .~
elevated levels of site-related contaminants were being detected
in residential wells at random intervals and varying concentra-
tions. Due to the uncertainties associated with predicting:
contaminant flow in ground water, PADER issued a drinking water
advisory and began to provide bottled drinking water to 44
residential units in March 1989 as an interim remedial action.
While the primary health risks from contaminated well water have
been addressed, the residents remain potentially exposed to
volatile contaminants when bathing or washing with well water.
The geology at the site is complex, and thus the testing
completed during the RI did not succeed in identifying or
predicting preferential. flow pathways for contaminants to move in
the subsurface. Based on historical sampling data, it appears
that a contaminant plume originating at the landfill may have
existed at one time. The RI data, however, did not succeed in
defining the extent of such a plume nor did it show that any
plume exist. currently. The data also did not suggest that such
a plume will develop in the future.
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21
VII. SUHMARY OF SIT! RISIS
The Public Health Evaluation addresses the human health and
env~ronmental impacts associated with the existing contamination
at the Walsh Landfill Site. The evaluation 'assesses the risks
associated with the no action alternative, or the risks posed in
the absence of remedial corrective action.
The public health evaluation is based on the results of
sampling completed during the RI (1987,1988), and residential
well s~mpling completed during 1989. This sampling data were
reviewed to identify chemicals that would be evaluated during the
public health evaluation. A selection process was used to
identify the chemicals present at the site that pose the greatest
potential public health risk. Chemicals were selected for
detailed evaluation if they were present in environmental media
at levels above background concentrations and based on their
characteristic toxicity, mobility, persistence, and quantity.
The primary risks posed by the site are the contaminated
drinking water supply and the landfill soils and sediments. The
concentrations of individual contaminants (maximum, minimum,
average concentrations) that contribute to this risk are
described in Tables A, B, and C.
The response actions for the. first OU will remove these
risks, stabilize the site, and substantially reduce further
degradation of the ground water aquifer at the site. The
response actions will serve to rapidly and permanently address
the primary risks to the local residents (contaminated well
water) that have been present for over two years. The response
action will also remove additional risks that may be caused by
the continuing salvage and solid waste transfer operations by
requiring these operations to cease.
A. !Z1)osur. A.......nt sn_-ary
The goal of the exposure assessment is to determine the type
anc magnitude of potential human exposure to the contaminants
present at, and migrating from, the Walsh Landfill site. The
exposure assessment was conducted to estimate the risk imposed by
the site if no remedial action was taken.
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22
To determine if human and environmental exposure to the
contaminants of concern might occur in the absence of remedial
action, an exposure pathway analysis was performed. An exposure
pathway is comprised of four necessary elements: 1) a source and
mechanism of chemical release; 2) an environmental transport
medium; 3) a human or environmental exposure point, and 4) a
feasible human or environmental exposure route at the point of
exposure. This section of the ROD summarizes the potential for
completion of exposure pathways at the Walsh Landfill Site.
1. Air Bxoo8ure Pathway and PODulation
There are two potential release mechanisms to be considered
in evaluating the air pathways: release of contaminated
particulates and volatilization from surface soil, ground water
and surface water. The release mechanisms to the air are
fugitive dust generation and vOlatilization; the transport
mechanism is the air. The route for human exposure to
contaminated air is via inhalation. Potential exposure points
from the site are areas of human activity next to the- site and~
residential users of contaminated ground water for showering arid
bathing.
The population potentially exposed via the air pathway
includes the residents of the approximately 49 homes near the
site and workers at the landfill.
2. Soil Exoosure Pathway and PODulation
The two potential release sources for the soil pathway
include the contents of the landfill and contaminated soils.
The release mechanisms are fugitive dust generation and
deposition, tracking, surface runoff, and leaching: the transport
media are the surface and subsurface soils, and surface water
sediments. The routes for human exposure include ingestion,
inhalation, and dermal contact. Potential exposure points from
the site include areas- of human activity on and adjacent to the
site. .
The population potentially exposed via the soil pathway
includes adults and small children from approximately 49 homes in
the landfill area. Onsite workers could also be exposed via
incidental ingestion and dermal contact.
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23
3. Ground Water IXDosur8 Pathway and Poculation
The two potential release sources for the ground water
pathway include landfill contaminants and contaminated soils.
The release mechanism is site leaching and the transport medium
is the ground water in the soil overburden and bedrock aquifers.
Human exposure routes to contaminated ground water include
ingestion, inhalation and dermal contact. Potential exposure
points from the site are potable wells in the local area that
withdraw contaminated ground water.
The population potentially exposed via the ground water
pathway includes the residents from approximately 49 homes near
the site with potable wells. This group includes those residents
who are currently receiving bottled water supplies.
4. Surface Water BXDo8ur8 Pathway and Poculation
The two potential release sources for the surface water
pathway include contaminated soils and ground water. The release
mechanisms are surface runoff and ground water seepage: the
transport mechanism is surface water originating from local
ground water discharge and the headwaters of the West Branch of
Brandywine Creek. The routes for human exposure are via dermal
contact and incidental ingestion: surface waters are not known to
be used as a potable water supply.
The population potentially exposed via the surface water
pathway includes small children who reside in the 49 residential
structures near the site. Environmental receptors may include
aquatic species living in the surface waters and cattle using
surface water as a drinking supply.
BT Toxicitv A88e88..nt S11m1lllary
The purpose of the toxicity assessment is to weigh available
evidence regarding the potential for site-related contaminants to
cause adver8e effects in exposed individuals, and to provide an
estimate ot the relationship between the extent of exposure to a
contaminant and the increased likelihood and severity of adverse
effects.
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24
Table D summarizes the public health and environmental
criteria for the contaminants of concern at the site. This
information is developed usi~g data on the fate and transport, or
distribution relationships (transport between air, water, soil,
and biota), of individual contaminants, and the documented health
effects or health hazards posed by individual contaminants. The
toxicity of contaminants is determined based on the observed
effects on humans and/or laboratory animals, and is obtained from
published literature describing epidemiologic or toxicologic
studies. Table D primarily summarizes health-related
information for the contaminants of concern at the site, and
includes such data as: enforceable standards for public water
supplies; and classification of contaminants as carcinogenic or
non-carcinogenic.
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, are
multiplied by the estimated intake of potential carcinogen
mg/kg-day, to provide an upper bound estimate of the excess life-
time 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 under-
estimation of the actual cancer risk highly unlikely. CPFs 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.~
Reference doses (RFDs) have been developed by EPA for
indicating the potential for adverse health effects from exposure
to chemicals'exhibiting noncarcinogenic effects. RFDs, which are
expressed in units of mg/kg-day, are estimates of lifetime daily
exposure levels for humans, including sensitive individuals.
Estimated intakes of chemicals from environmental media can be
compared to the RFD.. RFDs are derived from human epidemiological
studies or animal studies to which uncertainty factors have been
. applied. These uncertainty factors help ensure that the RFDs
will not underestimate the potential for adverse noncarcinogenic
effects to occur. .
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"
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26
C. Risk Characterization Summary
The risk characterization process is the final step in
completing the public health evaluation for the site conditions.
In this step, the toxicity and exposure assessments are
summarized and integrated into quantitative and qualitative
expressions of risk. To characterize potential non-carcinogenic
effects, comparisons are made between projected intakes of
substances and toxicity values. To characterize potential
carcinogenic effects, probabilities over a lifetime that an
in~ividual will develop cancer due.to site-related exposure are
estimated from projected intakes and chemical-specific dose-
response information. In addition, comparisons are made between
chemical-specific ARARs and estimated concentrations of
constituents of concern. These comparisons include: (1) an
average exposure (AE) scenario using the mean concentrations of
the medium-specific sample results and average values for each
parameter in the exposure assessment equations: and (2) a worst-
case exposure (WCE) scenario using the maximum constituent
concentrations from the media-specific sample results and the --
upper end range (90th or 95th percentile) for each parameter in
the exposure assessment equations. The exposure scenarios are
then used to estimate individual risks.
.~
Excess lifetime. cancer risks are determined by multiplying
the intake level with the cancer potency factor. These risks are
probabilities that are generally expressed in scientific notation
(i.e., 1 x 10-6). An excess lifetime cancer risk of 1 x 10.6
indicates that, as a plausible upper bound, an individual has a
one in a million chance of developing cancer as a result of site
related exposure to a carcinogen over a ?O-year lifetime under
the specific exposure conditions at the site.
!
Potential concern for noncarcinogenic effects of a single
contaminant in a single medium is expressed as the hazard
quotient (HQ). The HQ is determined by calculating the ratio of
the estimated intake derived from the contaminant concentration
in a given medium to the contaminant's reference dose. By adding
the HQs for all contaminants within a medium or across all media
to which a given population may reasonably be exposed, the Hazard
Index (HI) can be generated. The HI provides a useful reference
point for gauging the potential significance of multiple
contaminant exposures within a single medium or across media.
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27
Tables E, F, and G summarize the potential carcinogenic and
noncarcinogenic risks posed to adults, children, and landfill
workers who maybe exposed to site-related contaminants via the
associated exposure pathways. These tables present calculated
health risks for exposure to each contaminant of concern via the
average and worst-case exposure scenarios. Each table also
presents a total for the combined risks (carcinogenic and non-
carcinogenic) posed by exposure to all contaminants via the
combination of exposure pathways that are reasonably expected to
affect the human receptors for the Site (i.e., adults and
children residing near the landfill and landfill workers).
When reviewing the quantitative information presented in
these summary tables, the following threshold levels should be
used. For noncarcinogenic risks, a chronic hazard index value
above a value of 1.0 indicates the potential for an adverse
health impact. For the carcinogenic risks, a value greater than
the 10.4 to 10-6 is generally recognized as indicating a risk
beyond the acceptable level.
Tables E, F, and G show that the highest health risks are
posed by the worst-case exposure scenarios, or exposur~ via
combined pathways to the maximum concentrations of site-related
contaminants. The child receptors, or children in the local
community, appear to have the highest potential health risk from
exposure to the site conditions. While the health risks posed by
the average exposure scenarios do not appear to reflect an
elevated risk, there are several factors which make consideration
of the worst case scenario more realistic for decision making on
the basis of protectiveness. These factors include the absence
of control for site access and the continuing waste and refuse
handlinq and. disposal practices at the site. The specific nature
of the continued operations at the site are undefined, but it is
likely that hazardous substances are being handled, and possibly
stored and/or disposed of, on and around the site property, to
which access is readily available. Due to these circumstances,
it is more realistic to view the risk levels calculated through
the worst case scenarios as protective of human health and the
environment.
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,,-()
TABLE E
WELSH ROAD/BARKMAN LANDFILL SITE
TOTAL CHRONIC HAZARD AND RISK FROM POTENTIAL CARCINOGENS
CHILD RECEPTOR
CHRONIC HAZARD INDEX
Constituent Inhalation Oral Dermal Contact
AE WCE AE WCE AE WCE
1,1- Dichloroethane 2.2 x 10-3 8.0;lt 10-2 4.5 x 10-4 4.2 x 10-3 3.4 x 10-7 3.2 x 10-6
Chloroform 7.0 x 10-3 4.0 x 10-1 1.6 x 10-5 4.0 x 10-4
Benzene
Ethylbenzene 4.3 x 10-4 1.1xl0-2 3.2 x 10-7 8.5;1t 10-6
Xylenes 4.8 x 10-4 6.6 x 10-2 2.4 x 10-5 8.1 x 10-4 1.8 x 10-8 6.2 x 10-7
Trichloroethylene
Tetrachloroethylene 5.1 x 10-3 1.4 x 10-2 3.8 x 10-6 1.1 x 10-5
PAHs
Arsenic: 1.5 It 10-1 2.4 1.2 It 10-2 1.0 It 10-1
Cadmium 2.4;1t 10-1 4.3 1.9 x 10-2 2.5 It 10-1 .
Lead
Mercury 4.2 It 10-3 1.3 3.1 x 10-6 9.7 x 10-4
Nickel - 3.0 x 10-2 5.0 x 10-1 2.2 x 10-3 3.0 x 10-2
TOTAL 2.6 x IG-3 1.5 x 10-2 4.4 x 10-1 8.9 3.4 x 10-2 3.8 x 10-1
TOTAL CHRONIC HAZARD INDEX AE: 4.7z 10-1 WCE: 9.4
AE - Average Exposure Scenario
WCE- Worst-case Exposure Scenario
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~'j
TABLE E - CONTI:\fUED
WELSH ROAD/BARKMAN LANDFILL SITE
TOTAL CHRONIC HAZARD AND RISK FROM POTENTIALCARCINOGE:\fS
CHILD RECEPTOR
POTENTIAL CARCINOGENIC RISK
Constituent Inhalation Oral Dermal Contact
AE WCE AE WCE AE WCE
1,1- Dichloroethane 3.3 x 10-7 6.1 x 10.6 2.5 x 10.10 4.6 x 10-9
Chloroform 2.2 X 10.6 1.0 x 10.3 3.4 x 10.8 3.9 x 10-6 7.7 x 10.11 3.7 x 10-9
Benzene 4.8 x 10.7 2.8 x 10-5 1.1 x 10- 7 1.5 x 10-6 7.9 x 10.11 1. 1 x 10.11
Ethylbenzene
Xylenes
Trichloroethy lene 2.1 x 10-7 3.6 x 10-5 3.9 x 10-8 1.6 x 1()-6 2.9 x 10-11 1.2 x 10.9
Tetrachloroethylene 5.7 x 10.8 1.3 x 10.6 2.1xl0.7 1.1 x 10-6 1.5 x 10-10 8.6 x 10-10
PAHs 5.0 x 10-8 1.6 x 10.6 3.1 x 10-6 8.1 x 10.5 6.3 x 10-6 1.2 x 1()-4
Arsenic 1.4 x 10-5 2.0 x 10-4' 1.5 x 10-5 5.6 x 10-4 1.7 x 10-6 2.2 x 10-5
Cadmium 5.6 x 10-7 1.7 x 10-5
Lead 9.4 x 10-9 5.1 x 10-7 2.4 x 10-7 2.5 x 10-5 3.2 x 10-8 1.6 x 10.6
Mercury
Nickel 7.1 x 10-7 2.2 x 10-5
TOTAL 1.9 x 10-6 1.3 x lQ-3 1.9 x 10-6 6.8 x 10-4 8.1 x 10.6 1.4 x'10-4
TOTAL POTENTIAL CARCINOGENIC AE: 4.8 z 10-5 WCE: 2.2 z lC)-3
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TABLE F
WEI.811 ROADIBARKMAN LANDt'ILLHITE
TOTALCIIRONIC IIAZARD AND RISK FROM POTENTIAL CARCINOGENS
ADULT RECEPTOR
CIiRONIC "AZARD INOEX POTENTIAL. CARCINOGENIC RISK
COnlUtuon& InhalauoD Oral Dermal Contac:& Inhalation Oral Dcrlllul COlilucl
AE WCE AE WCE AE WCE At: WCE AE WCE AI:: W{;I::
I,I-Dichloroethane 6.. II 10. 2.11110" 2.7 II 10" 2.6 II 10" 2.8 II 107 2.711108 3.01 10.7 9.311011 :1.1 1 10 IU !*.H dO ~
Chloroform ..21110~ 2.~1I101 ... II 108 2.61110. 8.6 II 10.7 6.6 1 10'. 3.11108 6.0 II 10 6 3.21 10 II li.:11 10 ~
Ben1ene 1.91101 1.8 110 ~ 9.61108 2.311011 1.0 1 10 III 2.41 10 ~
Ethylbenune 2.6 II 10" 6.81110" 2.7 II 107 7.211 108
Xylene. 1.2 II 10. 1.7 II 10.2 1.61110" 6.01110. 1.6.108 6.21107
Trichloroethylene 8.2 1 10 8 2.3110~ 3.61 1011 2.51 106 3.71 10 II 1.1; 1 10 ~
Tetrachloroethy lone 3.01110' 8.611 10" 3.211 108 9.0 II 10 8 2.21 108 8.31 107 1.91 101 1.71106 1.9 1 10 IU I.H 1 10 11
PAil. 9.3 II 109 6.41101
A rMRie 3.911 102 9.71110.1 4.11I10~ 1.01 10' 2.71108 6.9 1 10 ~ 8.2 1 10.6 6.lh 10. 11.6110 11 7.1.10"
Cadmium 6.61 102 U 6.81 1011 1.4110' 1.0 1 10 7 5.71108
tead 1.8 1 10 9 1.71 10 7 9.41 10 II 2.2110~ !J.71 10 II 1.:1 1 10 b
Mercury 2.6110' 7.8110.1 2.61108 8.2110.
Nickel IUIIO' 1.611101 9.2.108 1.7110. 1.3 1 10 7 1.61106
TOTAL 6.8 1 10. 3.81102 1.21 101 3.6 1.3.10. 3.71 10' 4.111106 1.9..0. 9.01 10 II 1.2.10. !*.:J. 1011 '1.li 110"
TOTALCIIRONIC IIAZARD INUEX
AE: 1.2 II 10.1
WCE: 3.8
TOTAL POTENTIAL CARCINOGENIC RISK
AE: 1.3" IO~
wet:: I.:). 10 ~
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TA8LEG
WELSH ROAD/8ARKMAN LAN 1}Jt'1 LL SITE
TOTAL CHRONIC HAZARD ANI) RISK FROM POTENTIAL CARCINOGENS
LANDFILL RECEPTOR
CHRONIC HAZARD INDEX POTENTIAL CARCINOGENIC RISK
Constituent Oral Dermal Contact Inhalation Oral Dermal ContacL
AE WCE AE WCE AE WCE AE WCE Ag WCE
1,1- Dichloroethane 6.2 x 10-6 4.4 I 10-4 1. I x 10-7 1.6 x 10.6
Chloroform 9.7 x 10-4 4.3 x 10-2 3.6 x 10-6 2.2 x 10-5 4.7 x 10-11 3.2 x 10.10 1.2 x 10.8 1.0 x 10.6 4.2 x 1011 5.4 x to 11
Benzene 3.7 x 10.8 4.0 x 10.7
Ethylbenzene 6.9 x 10.6 1.2 x 10-3
Xylenes 3.4:11 10-8 8.6:11 10-6
Trichloroethylene l.4x 10.8 4.3 x 10-7
Tetrachloroethylene 7.0 x 10.4 1.6 x 10.3 7.lxIO.8 3.0 x 10-7
PAils 2.9 x 10-1 4.4 x 10.6 6.0 x 10-8 4.9 x 10-7 2.6 x 10.6 7.4 x 105
Arsenic 9.9 x 10-3 1.7 x 10-1 4.0 x 10-3 2.5 x 10-2 8.4 x 10-6 5.6 x 10-4 3.5 x 10-6 1.2 x 10-4 1.4 x 10.6 1.7x 105
Cadmium 1.6:11 10-2 2.4:11 10-1 2.6 x 10-3 3.4:11 10-2 3.3 x 10-6 4.7 x 10-6
Lead 6.5 x 10-8 1.4 x 10.6 4.2 x 10.8 3.9 x 10-6 2.6 x 10.8 1.2 x 106
Mercury 6.7 x 10-4 1.3 x 10-1
Nickel 2. I x 10.3 2.7 x 10-2 2.9 x 10.4 4.0 x 10-3 4. I x I 0-6 6.2 x 10.6
TOTAL 3.0 x 10.2 6.1 x 10-1 6.8 x 10.3 6.3 x 10.2 9.2 x 10.6 6.8 x 10-4 3.8 x 106 1.3x 10.4 4.0 x 10.6 9.3x 1115
w
..-
TOTAL CHRONIC HAZARD INUEX AE: 3.7 x 10-2 WC"~: 6.8 x 10~1
TOTAL POTENTIAL CARCINOGENIC AE: 1.0 x 10-4 WCE: 8.9 x 10-4
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D. Uncertainty Analvsis
The procedures and inputs used in the public health
evaluation for the Walsh Landfill site are subject to
uncertainties. In general, the main sources of uncertainty
include: environmental chemistry sampling and analysis;
environmental parameter measurement; fate and transport
modelling; exposure parameter estimation; and, toxicological
information. Each of these sources of uncertainty is discussed
in detail in the Public Health Evaluation Report completed by
BakerfTSA, Incorporated. This report is part of the
Administrative Record for the site."
B. Risk Assessment Conclusions
The Walsh Landfill Site's surface soils and ground water
have a significant potential adverse health impact on receptor
populations as calculated by the chronic health index and the
risk from potential carcinogens indices. There were three
complete exposure pathways identified: the air exposure pathway
via inhalation of ground water and particulates by receptors; the
ground water exposure pathway via ingestion, inhalation, and
dermal contact by receptors of water supply wells; and, the soil
exposure pathway via ingestion and dermal contact by receptors.
The air pathway was not.deemed to represent a significant
health hazard with respect to the volatilization of organics from
the surface waters or from surface soils. However, the air
pathway was deemed to represent a potential health hazard from
inhalation of volatile organics during showering and bathing and
fugitive dust caused by vehicle traffic. The chemicals
contributing the most significantly to the potential adverse
health impacts and risks from the inhalation of volatile organics
included chloroform, benzene, trichloroethylene and
tetrachloroethylene. These contaminants were detected in the
ground water samples collected during and after the RIfFS. The
exposed population included childre~ and adults living in the
local area and using the ground water for domestic purposes. The
chemicals contributing the most significantly to the potential
adverse health impacts and risks from fugitive dust inhalation
included PABs, arsenic, cadmium, lead and nickel. The exposed
population included landfill workers and local residents living
downwind of the landfill.
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33
The soil pathway was identified as a health hazard from
ingestion and dermal contact exposure to contaminated surface
soils and sediments. The landfill workers dre potentially at
risk from dermal contact with surface soils contaminated with
PARs, arsenic, and lead. In addition, the children in the area
are potentially at risk from ingestion and dermal contact with
sediments contaminated with PAHs and lead. However, only the
sediments found onsite at location SED-4/0PT (See Fiqure 2) were
contaminated with PAHa and lead.
The ground water exposure pathway represented a potentially
significant health risk, as indicated by chronic health index
values greater than one, and projected carcinogenic risk values
above the target risk values of 1 x 10-6. The compounds con-.
tributing the most to the potential health impacts were 1,1-
dichloroethane, chloroform, benzene, trichloroethylene, tetra-
chloroethylene, arsenic, cadmium, lead and mercury. The exposed
population inc~udes children and adults living and working in the
local area and using the ground water for domestic purposes. The
exposed population has been preliminarily defined as the 49
residences situated along PA Route 10 and Welsh Road, whose water
supply wells were sampled during the RI/FS, and where contam-
inants were detected at elevated levels. In addition, residences
situated along the general direction of regional ground water
flow are included in the group as potentially impacted by
contaminated ground water in order to address possible future
health impacts. .
Future land use in the site area will include residential
dwellings and farming. Honeybrook Township and the Borough of
Honey Brook have expressed a desire to control future development
by restricting growth to that of a farming or low-density
residential nature within the municipalities wher. the Walsh site
is located. To this end, future growth is likely to be
controlled by the local government's zoning and permitting
process.
Based on the li.ited information available, the surface
water exposure pathway did not appear to represent a significant
risk to huaan health. The metals cadmium and lead occurred at
concentrations above their respective ARARs for protection of
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34
aquatic life at locations SW-l and SW-4 (See Figure 2). However,
these contaminated surface waters did not support a diverse or
highly productive aquatic life community. In addition, these
surface waters are present on an intermittent basis, and depend
greatly on precipitation. The remedial action selected for this
operable unit will involve capping the landfill surface, which
includes the areas of periodically ponded water.
Actual or threatened releases of hazardous substances from
the Walsh Landfill Site, if not addressed by implementing the
response action selected in this ROD, may present an imminent and
substantial endangerment to the public health, welfare, or the
environment.
VII. DBSCRIPTION OP ALTERNATIVES
Five remedial alternatives were retained from the
feasibility study to address the first OU. These alternatives
were designed to eliminate or reduce the health risk posed to ;the
local community by exposure to contaminated ground water and;.:
landfill soils. Each alternative was evaluated against the .,
following criteria: the overall protection of public health and
the environment; how well the action complies with State and
Federal laws and advisories (ARARs): its short-term
effectiveness: its long-term effectiveness; how well. the action
reduces toxicity, mobility, and volume; the implementability of
the alternative; the acceptance (or rejection) of the alternative
by the State and community: and the total cost of the
alternative. Table ES-l presents a summary of the detailed
evaluation that was completed using these criteria. Table ES-l
also includes cost figures for each alternative, and Table H
provides a detailed cos~ breakdown for the- selected remedy.
Remedial Action Alternative. No.1 - No Action
The No Action alternative is required by the National
Contingency Plan (NCP) for consideration during the detailed
analysis and is included for purposes of comparison. If No
Action was chosen at the Walsh Landfill Site, the present and
future potential health risks. would go unabated. The No Action
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35
alternative does not meet SARA's mandate to be protective of
public health and the environment. It is also very unlikely that
the state or community would accept No Action at the aite.
The No Action alternative includes no remedial action to
clean up contamination or to address risks posed by the site.
The current provision of bottled drinkinq water would cease;
however, this alternative would provide for continued qround
water monitorinq. This monitorinq consists of the annual
collection, analysis, and evaluation of qround water samples
collected from site monitorinq wells, piezometers, and
residential wells, to further define the extent, miqration, and
fate of indicator contaminants and to track contaminant movement
in the qround water. The results of the samplinq would be used
to assess any risks and to provide a baseline with which future
results and risks may be compared. Detailed reviews of site
conditions as required by CERCLA would be performed at five-year
intervals.
Remedial Action Alternative .0. 2 - In8~itution.l Action8
Alternative NO.2 consists of four activities: expansion of
an existinq water supply system; qround water monitorinq;
fencinq; and, property deed modifications. The principal
activity is the expansion of the Honey Brook Borouqh Water
Authority's water supply system to provide a lonq-term source of
potable water to residents affected by contaminated water in the
site vicinity. An eiqht-inch main line from the Honey Brook
Water Supply System currently extends to a location approximately
one mile south-southwest of the landfill. This eiqht-inch line
would be extended to, and alonq PA State Route 10 to a storaqe
tank near the top of Welsh Mountain. From the storaqe tank the
water would be distributed by qravity flow throuqh 2-inch and 4-
inch mainlines to approximately 50 households. The water supply
system expansion involves two components: extension of the
current system; and upqrade of the system capacity.
The major components of the water supply system extension
include an eiqht-inch mainline, four-inch and two-inch
distribution lines, a booster pump, and a 120,000 qallon water
storaqe tank. This desiqn may be affected by ordinances imposed
by Honeybrook Township which may require usinq minimum six-inch
distribution lines. These ordinances may also include mandatory
well abandonment and connection to the new system for domestic
use.
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36
The water supply system upgrade consists of the installation
of one water supply well and connection of this well to the
current distribution system. It is estimated that this water
well will increase the current system capacity by an estimated
115,000 gpd. This should provide sufficient additional system
capacity to supply affected residents with potable water as well
as to satisfy fire flow demand.
The approximately 50 households to be serviced by "the water
line extension comprise the group of homes whose wells were
sampled during the RIfFS. These homes have been identified as
those presently or potentially at risk from contaminated ground
water from the site. Ground water monitoring activities will
include the sampling of site monitoring wells to track
contaminant movement, and further define the migration and fate
of site-related contaminants to ensure that homes outside of the
water line extension area will not be at risk. Through this and
the work to be performed for the second OU, the ground water flow
dynamics will be defined, and EPA will be better able to identify
any additional homes that may be impacted by contaminated ground
water. . ~
EPA (and the State) will not be responsible for the
operation and maintenance of the water supply system once it is
operational. Control of the new water. lines will be transferred
to the Honey Brook Borough Water Authority as soon as
construction is complete. Therefore, construction details must
meet the reqUirements of Honey Brook Borough and Honeybrook
Township, as well as local fire codes.
Additional activities include the construction of a six-foot
high fence topped with either barbed. wire or razor ribbon around
the perimeter of the landfill. It will be necessary to locate
property boundaries and the lateral extent ~f the landfilled
material prior to constructing the fence. The fence is designed
to restrict access to the site and prevent use of the property
for continued or future waste disposal. In addition, deeds for
properties. underlying, or in the vicinity of the landfill would
be modified to indicate the landfill presence, restrict future
use and property development, and restrict the use of ground
water by preventing the installation of wells on the property.
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37
This alternative could be implemented relatively quickly; it
is expected to take approximately one year to design and
construct the water line extension. Coordination with the Honey
Brook Borough, Honey Brook Borough Water Authority, Honeybrook
Township, and the Chester County Health Department will be
required for the construction of the water supply system
expansion.
The techniques involved in connecting the residences to a
public water system are well established and use common
engineering and construction practices. Generally, public water
systems are very reliable and require only limited maintenance.
The water quality of the proposed system will be regulated by the
National Primary Drinking Water Regulations and the Pennsylvania
Water Quality standards, in conjunction with the requirements of.
the Chester County Health Department and the Honey Brook Borough
Water Authority. This action will be in compliance with the
ARARs for the Walsh Landfill Site.
This alternative will require the approval of the Honey
Brook Borough.Water Authority. The Authority is currently
planning to expand their system's capacity. Through preliminary
discussions with EPA and the State, the Authority has indicated
that this proposed extension to service the approximately 50
homes will fit within the scopa of their system's design. The
Authority has expressed concern with the well abandonment issue,
and may pursue making abandonment mandatory for those households
being hooked up to the water line extension.
Remedial Action Alternative _0. 3 - Institutional Action.
Alternative three consists of four actions: bottled water
supply: ground water monitoring: fencing: and property deed
modifications. This alternative is similar to RAA NO.2, with
the primary difference being the use of bottled water rather than
the expansion of a water supply system. Based on the supply
schedule currently in place, it is estimated that approximately
44 to 50 households would require delivery of three cases of
bottled watar every two weeks to be used as their drinking water
source.
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These residents will continue to use their well water for washing
and bathing activities, which may expose the residents to
volatile organics detected in ground water via the inhalation
exposure pathway. This alternative therefore is not protective
of human health, but it is included based on input received from
the community. Several residents expressed a desire to continue
receiving bottled water as a permanent remedy for contaminated
ground water exposure, regardless of any continued health risk.
As with RAA NO.2, ground water monitoring activities
involving the sampling of site monitoring wells and residential
wells on an annual and five-year review basis will be completed.
This monitoring will serve to track contaminant movement, and to
aid in the further definition of the migration and fate of site-
related contaminants. This monitoring will assist in identifying
any additional homes that may be impacted by contaminated ground
water.
The fencing and property deed modification activities ...
included in this alternative are identical to those described for
RAA No.2. The fencing will serve to restrict site access, but
does not address threats posed by fugitive dust. Long-term
management of this alternative will require periodic site
inspections to assess changes in site conditions and usage of the
site by local residents or the owner. Five-year reviews, .
including sampling of wells, an assessment of risks posed by the
site, and an inspection of the integrity of the fence will be
required.
Remedial Action Alternative .0. 4 - In8titutional and Containment
Action8
Alternative number four includes both institutional and
containment actions to address risks posed by contaminated ground
water and onsite contaminated materials. This alternative
consists of six activities: expansion of an existing water supply
system; ground water monitoring; fencing; property deed
modificationa~ resource recovery; and capping. The first four
activities were described previously for RAA No.2.
The resource recovery activities may include, but will not
be limited to, salvaging the items found on, or near the surface
of the landfill such as cars, buses, appliances, storage tanks,
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39
dumpsters, batteries, and tires. These items will be
decontaminated, if necessary, and removed from the site by
qualified salvaging subcontractors. The decontamination of the
bulky items would be completed in a designated and specially
constructed area on or near the site. Any water generated during
the decontamination would be contained and sampled for analysis
prior to properly disposing of it. The resource recovery
activities include demolition of onsite buildings and the
excavation and removal of underground storage tanks that may be
present at the site. The purpose of the resource recovery action
is to remove recoverable or salvageable materials from the site
in a cost effective manner so that the landfill volume may be
reduced, and the landfill surface may be graded and prepared for
capping.
This alternative includes capping the landfill to reduce
infiltration from precipitation and to prevent potential exposure
to onsite contaminated materials. At a minimum, a multi-media
landfill cap that meets the requirements of the Pennsylvania
Municipal Solid Waste Requlations will be constructed at the
site. In general, the municipal or multi-media cap consists of a
soil cover having a topsoil component underlain by a thick soil
layer, a drainage layer with a permeability greater than 1 x 10 .
3 em/second, a high density polyethylene (HDPE) geomembrane, and
a base soil layer over the landfill. The overall thickness of
the municipal or multi-media cap is approximately four feet.
Prior to the design and construction of the landfill cap, it
will be necessary to collect additional information to ensure
that the cap is properly constructed for the site conditions.
Upon completing these pre-design or investigatory activities, the
information will be reviewed, and incorporated in the design
documents for the landfill cap. pre-design activities will
include, at a minimum, the followinq:
Survey property lines, landfill extent, surface
topoqraphy of landfill and surroundinq areas, power
lines, easements and rights-of-way:
Determine the contents of the landfill and landfill
geotechnical parameters (i.e., moisture content,
compactibility);
Characterize site soils;
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!
40
Locate and characterize borrow soil properties; and
Determine the potential for the landfill to
methane or other gases, and. measure VOC and
levels in the landfill gas to determine the
venting.
generate
methane
need for
The information generated during the pre-design activities
will be evaluated and incorporated into design documents for use
during implementation of the remedy. If available, data to be
generated during the focused ground' water study for the site will
also be considered in designing the landfill cap and surface
water runoff control measures.
The landfill cap will be designed to cover an approximate
surface area of 5.2 acres. The exact size of the surface area to
be capped may be subject to change once the resource recovery
action is completed, and the landfill area has been surveyed.
The top slopes of the cap will be approximately three percent,
minimum, and unbenched side slopes of a maximum of fifteen .:
percent. When the side slopes are greater than 15 percent, a c..
bench may be used for every 25-foot rise in elevation. Both top-
and side slopes will be vegetated, and gas vents may be installed
pending a review of the information collected during the pre-
design activities. In addition, surface water control measures"
will be implemented as part of 'the landfill cap. A fence will be
constructed around the perimeter of the capped area to restrict
site access.
This combination of institutional and containment actions is
expected to provide both short- and long-term protection of human
health and the environment. Long-term management of this
alternative includes continued ground water monitoring and
perio~ic inspections of site conditions. Five-year reviews,
including an assessment of risks posed by the site, an inspection
of the landfill cap's integrity, and an inspection of the
integrity of the fence will be required. Limited repair and
maintenance activities may be required on the cap and fence.
RAA NO.4 will address the principal threats posed by the
site, and provides a permanent solution to the drinking water and
landfill problems, as well as the nuisance issues associated with
the continued junkyard operation. The extension of an existing
water supply to service approximately 49 residential structures
impacted b~ contaminated ground water employs. well established
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41
construction techniques and engineering practices. The water
line extension is easily implementable, and should be completed
within one year, thus' providing rapid relief to those individuals
who may be exposed to contaminants when bathing or washing with
well water. The design and construction of the landfill cap also
employs well established engineering and construction techniques,
and is easily implementable, with an approximate completion time
of 18 to 24 months. The total completion time for this
alternative is approximately two years, with a phased approach
planned in order to expedite the provision of safe drinking
water. This alternative is likely to be consistent with the
final, or ground water remedial action for this site.
Remedial Action Alternative No.5 - Institutional and containment
Actions .
This alternative. is identical to RAA NO.4, except that
bottled water will be provided as a source of potable water
rather than extending an existing water supply system. As with
alternative number four, the following activities will also be
completed: ground water monitoring: fencing: property deed
modifications: resource recovery: and capping. These activities
are described in greater detail under RAA No.2 and RAA No.4.
Alternative number five is somewhat protective of human
health: the threats to public health posed by the ingestion of
contaminated-ground water are addressed. However, the threats
posed by the inhalation exposure pathway are not addressed. This
alternative is not protective of human health, but was retained
due to'the community's expression of preference for this method
of receiving safe drinking water.
This method of providing safe drinking water to the impacted
residences is not preferred by EPA. The bottled water will be an
effective remedy only as long as it is implemented. Providing
bottled water also i. not protective of human health due to the
concerns with inhalation of volatile organic contaminants during
. bathing. Under this alternative, the State would be responsible
for delivering bottled water to approximately 44 to 50
residential structures or households for an estimated period of
at least 25 years. For this reason, it is not anticipated that
the State would concur with this remedy.
Long-term management of this alternative includes continued
monitoring of ground water in site and residential wells,
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42
periodic inspections of site conditions, and possible repairs to
the fence and landfill cap. Five-year reviews, including an
assessment of risks posed by the site will also be required. The
total implementation time for this alternative is approximately
18 to 24 months.
1%. COMPARATIVW ANALYSIS OP ALTERNATIVES
The five remedial action alternatives described above were
evaluated under the nine evaluation criteria as set forth in the
NCP 40 C.F.R. Part 300.430(e) (9) and as described in the
"Guidance for Conducting Remedial Investigations and Feasibility
Studies Under CERCLA" (EPA, October 1988), EPA Directive 9355.3-
02 "Guidance on Preparing Superfund Decision Documents: The
Proposed Plan, The Record of Decision, Explanation of Significant
Differences,- and the Record of Decision Amendment" (EPA/540/G-
89/007), July 1989 Interim Final. These nine criteria are -
organized according to the groups below and can be categorized~
into three 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
Reduction of toxicity, mobility,
treatment
Implementability .
Short-te.rm effectiveness
Long-term effectiveness
Cost
or volume through
MODIFYING CRITERIA
Community acceptance
State acceptance
These evaluation criteria relate directly to requirements in
Section 121 of CERCLA, 42 U.$.C. Section 9621, which determine
the o~erall feasibility and acceptability of the remedy.
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43
Threshold criteria must be satisfied in order for a remedy to be
eligible for selection. Primary balancing criteria are used to
weigh major trade-offs between remedies. state and community
acceptance are mOdifying criteria formally taken into account
after public comment is received on the Proposed Plan. The
evaluations are as follows: .
1) OVerall Protection of Human Health and the Bnvironment
A primary requirement of CERCLA is that the selected
remedial action be protective of human health and the
environment. A remedy is protective if it reduces current
potential risks to acceptable levels under the established
range posed by each exposure pathway at the site.
and
risk
Alternative No.1, No Action, provides no protection for
human health or the environment. Alternatives 2 and 3 provide
some level of protection for human health and the environment.
Alternatives 2 and 3 provide some level of protection for huma~
health by reducing or eliminating potential ingestion of
contaminated ground water. Alternative 2 is somewhat more
protective than Alternative 3 in this respect because it also
eliminates the inhalation exposure pathway through the use of an
alternate water supply system as opposed to the use of bottled
water for drinking purposes. Both of these alternatives provide
a similar level of protection against exposure to onsite
contaminated materials with the erection of a fence to limit
access.
Alternatives 4 and 5 provide increased protection from on-
site contaminated materials by the placement of a cap over the
landfill in addition to a fence erected to limit access. Alter-
native 4 provides the highest level of protection by eliminating
the risks posed by all exposure pathways identified for the site.
2) ComDliance with ADDlicable or Relevant and AD~roDriate
Reauirement.
Under Section 121(d) of CERCLA, 42, U.S.C. Section 9621(d),
and EPA quidance, remedial actions at CERCLA sites must attain
legally applicable or relevant and appropriate Federal and State
environmental standards, requirements, criteria, and limitations
("ARARs"). Applicable requirements are those substantive
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44
environmental protection requirements, criteria, or limitations
promulgated under Federal or state law that specifically address
hazardous material found at the site, the remedial action to be
implemented, the location of the site, or other special
circumstances. Relevant and appropriate requirements are those
substantive environmental protection requirements, criteria, or
limitations promulgated under Federal or state law which, while
not applicable to the hazardous materials at the site, the
remedial action, site location, or other circumstances,
nevertheless address problems or situations sufficiently similar
to those encountered at the site that their use is well suited to
that site. . .
The remedy for the first operable unit will comply with all
of the ARARs of other Federal and State environmental laws.
3) Reduction of Toxicity Mobility or Volume
This evaluation criterion addresses the degree to which a,
technology or remedial alternative reduces toxicity, mobilitY"jor
volume of hazardous substance. section 121(b) of CERCLA,
42 U.S.C. Section 9621(b), establishes a preference for remedial
actions that permanently and significantly reduce the toxicity,
mobility, or volume of hazardous substances over remedial actions
which will not result in such reduction. .
Alternatives 1,2, and 3 do not reduce contaminant toxicity,
mobility, or volume through treatment. Alternatives 4 and 5
reduce the volume of materials through the implementation of
resource recovery activities to remove the bulky items present on
the landfill surface. Resource recovery is considered to be
physical treatment, and will address debris (appliances, .
vehicles, tanks, drums) present onsite. Alternatives 4 and 5
will also serve to reduce the mobility of contaminants, not
through treatment, but, through placing a cap over the landfill.
The cap will reduce infiltration through the landfill and will
thus reduce the quantity of contaminants that will leach to
ground water. Alternatives 4 and 5 will not reduce the toxicity
of contaminants that are present in the landfill.
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45
4) Imp1ementabi1ity
All remedial action alternatives are both technically and
administratively feasible. The activities included in each
alternative generally use standard construction techniques and
are of relatively high reliability.
Alternatives 2 and 4 will require some coordination between
state and federal agencies, the Honey Brook Borough Water
Authority, Honeybrook Township, and the Chester County Health
Department. Administrative issues associated with these
alternatives include: cessation of on-site operations, issuance
of property deed modifications and restrictions, and abandonment
of the residential wells prior to connection to the water supply
system.
5) Sber~-term Effectivenes8
Short-term effectiveness addresses the period of time needed
to achieve protection of human health and the environment, and
any adverse impacts that may be posed during the construction and
operation period until cleanup goals are achieved.
Alternatives 1,2 and 3 will not create additional short-term
risks to the community or workers above those identified in the
risk section of the ROD. Alternatives 4 and 5 will likely create
some acute risks, primarily to onsite workers, which may be
controlled by the use of personnel protective equipment.
6) Lena-term Effectiveness and Permanence
Long-term effectiveness and permanence addresses the long-
term protection of human health and the environment once remedial
action cleanup goals have been achieved, and focuses on residual
risks that will remain after completion' of the remedial action.
This section will address tha long-term effectiveness of the
limited scope of action for this ROD: landfill cap, alternate
water supply, and institutional controls.
Alternatives 2 and 4 address current risks to human health
posed by contaminated ground water. These alternatives provide
for an alternate water supply to eliminate both ingestion and
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46
inhalation exposure pathways for contaminated ground water.
contrast, alternatives 3 and 5 do not address the inhalation
exposure pathway.
In
Alternatives 4 and 5 include provision for the construction
of a landfill cap, and address current risks associated with
exposure to onsite contaminated materials. The containment
options (4 and 5) afford a higher degree of permanence than the
institutional controls (2 and 3) due to the physical barriers to
exposure provided by the cap. Alternatives 2 and 3 include
fencing to restrict site access, but these actions will not
necessarily provide long-term protection from exposure to on-site
contaminated materials.
Long-term management for all remedial alternatives includes
continued ground water monitoring with five-year reviews as well
as' periodic site inspections. Alternatives 2 through 5 will
require periodic inspection and repair of the fence. Alterna-
tives 4 and 5 will also require periodic inspection and repair of
the landfill cap.
7) Cost
CERCLA requires selection of a cost-effective remedy that
protects human health and the environment and meets the other
requirements of the Statute. Project costs include all
construction and operation and maintenance costs incurred over.
the life of the project. An analysis of the present worth value
of these costs has been completed for each alternative described
in this ROD and is summarized in Table ES-1. Capital costs
include those expenditures necessary to implement a remedial
action.
The costs of the five alternatives range from $1,258,000 to
$3,601,000. The degree of protection provided by the
alternatives also varies. Comparison of different levels of
costs for different levels of protectiveness and permanence of
treatment is a primary decision criterion in the cost-
effectivene.. evaluation.
Alternatives 2 and 4 are the highest in cost, yet offer a
higher level of protection by providing a permanent source of
safe drinking water to the affected residents. Alternative 4 is
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47
the most costly, and is also the most protective of human health
and the environment by providing permanent relief from exposure
to contaminated soils and ground water. A detailed breakdown of
the costs associated with Alternative 4 is provided in Table H.
The costs for the remedial alternatives are also subject to
change based on several influences. All of the alternatives were
sensitive to the cost of borrowed capital. Alternatives 1 and 3
were sensitive to the variation in O'M costs. The present values
of alternatives 2 and 4 varied significantly with changes in the
capital costs associated with the expansion of the existing water
supply system. Alternatives 4 and 5 are sensitive to variations
in the capital costs associated with capping.
8) .
Community AcceDtance
A public meeting on the Proposed Plan was held ~n March 27,
1990 in Honey Brook, Pennsylvania. Comments received from the
public at that meeting and during the comment period are
discussed in the Responsiveness Summary attached to this ROD.
') .
state AcceDtance
The Commonwealth of Pennsylvania has concurred with this
selected Remedial Action.
x.
SELECTED REDDY
Alternative 4: In.titutional an4 containaent Action8-
Bzten4 Municipal Water Line, LaD4till Cap, Acce... Control..
Based on the findings in the RI/FS and the nine criteria
listed above, the USEPA has selected Alternative 4. In the
judgement of EPA, Alternative 4 represents the best balance among
the evaluation criteria and satisfies the statutory requirements
of protectiveness, compliance with ARARs, cost effectiveness, and
the utilization of permanent solutions and treatment to the
maximum extent possible. Alternative 4 is selected as the most
appropriate remedy for meeting the goals of the initial operable
unit at the Walsh Landfill Site.
This alternative is an operable unit measure to prevent
human exposure (i.e., ingestion, inhalation, dermal contact) to
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48
TABLE H
WELSH ROAD/BARKMAN LANDFILL SITE
COST SUMMARY FOR THE SELECTED REMEDY
Cost Component Cost Estimate
Direct Capital Costs
1. Groundwater Monitoring $227,850
2. . Expansion of Existing Water Supply System 787,310
3. Fencing 30,750
4. Resource Recovery 13,525
5. ~unicipal Cap 1.125.600
Total Direct Costs $2,1~,035
Indirect Capital Costs
1. Engineering and Design (7~ of Direct Cost) 152,952 ~
2. Contingency Allowance (2~ of Direct Cost) 437.007
Total Indirect Costa $589,959
TOT AL CAPITAL COSTS 12,774,994
Operation and Maintenance Costa
1. Landfill Maintenance and Groundwater Monitoring Around Unit. $63,090
(Years 5, 10, 15,20 and 25)
2. Landfill Maintenance and Groundwater Monitoring Around Unit 108,950
(Years 2 through 4,6 through 9,11 through 14,16 through 19, and
21 through 24)
TOT AL COSTS ~
(Net Present Value calculated using a 5~ discOunt value)
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49
contaminated water and soils having concentrations of TCE,
chloroform, ethy1benzene, arsenic,lead, mercury, and other
cOuotituents in excess of Federal, State, and local health-based
ARARs. This alternative will remove the primary risks posed by
the site, and will also be consistent with a final remedial
action for this site. A summary of each of the major components
of this selected remedy is described below:
The extension of the Honey Brook Borough water supply system
will be designed to include the following components.
Specific parameters may be subject to change pending
completion of design and coordination with local and state
agencies.
I .
I
i
Construction of an approximate one mile extension of an
eight-inch-diameter mainline along PA state Route 10 to a
storage tank located near the top of Welsh Mountain. From
the storage tank, 2-inch and 4-inch mainlines will be placed
to distribute water by gravity flow to an estimated 50
households. The 50 households include those previously
sampled and those presently receiving bottled water. The
number and location of residences which will receive public
water will be verified during the design of this remedial
action.
Approximately 6500 feet of 8-inch water main, 7500 feet of
4-inch and 3000 feet of 2-inch distribution lines will be
installed along PA State Route 10 and Welsh Road. Service
lines will be installed for each of the approximately 50
households.
The current water supply system will be upgraded to provide
sufficient capacity to service the impacted residents. This
upgrade involves the installation of one water supply well
and connection of this well to the current system. A
booster pump and 120,000 gallon water storage tank are also
included in the required system upgrade. .
Control of the new water lines and services will be
transferred to the Honey Brook Borough Water Authority as
soon as construction is completed.
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50
Ground water monitoring data will be collected to monitor
the current contaminant levels and possible migration.
Wells will be sampled as part of the focused ground water
study to be completed for the second operable unit at the
site, which is planned to occur in tandem with the water
line design. A five year review will also include ground
water monitoring of site wells, with analysis for the full
list of CLF target parameters.
At a mininum, a multi~media landfill cap that meets the
requirements of the Pennsylvania Municipal Solid Waste
Regulations will be designed to contain the contaminated
soils and waste mat~rials present at the site. The initial
activities include resource recovery, or salvaging of bulky
items (cars, appliances, dumpsters, tires) presently placed
on top of the landfill, demolition of onsite buildings, and
excavation and removal of underground petroleum storage
tanks currently used to fuel vehicles used in the junkyard
operation. Additional information will be collected in
order to properly design the landfill cap, including:
survey landfill extent, power lines, easements, and rights~
of-way: characterization of the contents of the landfill,~
its potential to generate methane and other gases, and'
landfill geotechnical parameters: characterizing site soils:
and locating borrow soils with appropriate characteristics.
Results and findings from the focused ground water study
will also be considered in designing the landfill cap, if
available. . .
A six-foot high fence topped with either barbed wire or
razor ribbon will be constructed around the perimeter of the
landfill in order to restrict unauthorized site access and
the use of the property for continued or future waste
disposal.
Property deeds for the landfill area will be modified, where
appropriate, to indicate the landfill presence, restrict
future use and property development, and to restrict use of
ground water by placing limitations on the installation of
ground water wells.
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51
Cost
The estimated capital and annual operation and maintenance
costs for this alternative are summarized below. The present-
worth cost estimate is $ 3,768,000 which includes construction of
a multi-media landfill cap that at a minimum, meets the
requirements of the Pennsylvania municipal solid waste management
regulations.
capital Cost
IS 1.000s)
2,775
0'. Cost
CS1000s)
63 (annual)
109 (5-years)
pr.sent Worth
~
3,768
A more detailed breakdown of costs is presented in Table H.
XI.
STATUTORY DETBRMINATIONS
The selected remedy which was outlined in Section X
satisfies, in part, the remedy selection requirements of CERCLA
and the NCP. The remedy provides protection of human health and
the environment, achieves compliance with ARARs, utilizes
permanent solutions to the maximum extent practicable, and is
cost effective. The statutory preference for using treatment as
a principal element is not applicable to this operable unit.
This requirement will be addressed in the second operable unit
which will consider ground water remediation alternatives.
Of the five balancing criteria used in selecting the remedy
for the site, the long-term effectivess and permanence factor
were found to be the most important during the screening process.
Due to the history and continuing status of site operations, and
the apparent lack of environmentally sound practices, selection
of a permanent source control and alternate water supply remedy
was made to ensure protection of human health and the
environment.
The ..lected remedy for the first operable unit will be
protective of human health and the environment by reducing the
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52
principal threats posed by the current site situation. By
extending the-Honey Brook Borough municipal water supply, the
affected residents will be offered a permanent source of safe
drinking water. The landfill cap and site access controls will
prevent contact with contaminants present in sit~ soils and
sediments. The cap will also reduce the mobility of contaminants
which may flow into site ground water. This action therefore
reduces and controls the risks posed by the air pathway (fugitive
dust, shower inhalation), the soil pathway (dermal contact and
ingestion), and the ground water pathway (ingestion, dermal
contact, and inhalation).
The selected remedy provides the highest level of protection
utilizing permanent solutions for the position of the site which
poses the principal threats to human health and the environment.
This remedy is likely to be consistent with the selection of a
final, or ground water remedy for the site, and is cost-
effective. The resource recovery activities will reduce the
volume of contaminated materials and allow for preparation of the
~andfill surface for capping. The remaining alternatives were -
quite costly in proportion to their ability to provide protection
of public health with regard to the site conditions.
Implementation of the selected remedy should not pose any
short-term risks to local residents. The remedy will be designed
to include air monitoring around the site perimeter or work area,
and measures to limit the generation of dust during the use of
heavy equipment. A health and safety plan will be developed to
protect onsite workers or visitors from exposure to hazardous
substances during implementation of the remedy.
The selected remedy for this operable unit does not satisfy
the statutory preference for including treatment that reduces
toxicity, mObility, or volume as a principal element. The
Feasibility study evaluated incineration as a remedial
alternative for- the landfill materials in the initial screening.
While incineration is a viable process option, the conditions
under which the landfill contents were disposed of (mixed
municipal, industrial and construction wastes) may pose severe
difficulties to the implementation of incineration asa cleanup
alternative. S~rting and separation of the landfill contents
prior to incineration of any hazardous substances would pose
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1_."
53
extreme safety and health hazards to the onsite workers. In
. addition, potential health risks may be posed to the local
community from generation of fugitive dusts during implementation
of incineration activities. For these reasons, as well as
consideration of the cost effectiveness of incineration, EPA did
not select this treatment option for the landfill wastes. EPA
will consider treatment technologies for the contaminated ground
water as the second operable unit for the site.
ComD1iance with ARARa
Applicable or relevant and appropriate requirements (ARARs)
pertaining to this remedy will be attained. The selection of
this alternative has generated a limited number of ARARs, due to
common and accepted engineering and construction practices
associated with the installation of water mains and water service
connections. These requirements consist of state/local plumbing
and fire codes which are to be considered for the installation of
water mains, service connections, and fire hydrants. Also, the
residences targeted herein, are to be connected to the public
water system which must be in compliance with the National
Drinking Water Regulations, the Pennsylvania Water Quality
standards, and the requirements of the Chester County Health
Department and Honey Brook Borough Water Authority.
The ARARs and other nonpromulgated advisories and guidances
issued by Federal, state and local governments (TBCs, or "to-be-
considered" items) for the remedial action are discussed below.
It should be noted that due to the limited nature of this
operable unit, ARARs that apply to ground water cleanup will be
addressed in the final ROD for this site.
SDWA Kaziaua contaminant Level. (40 cpa Part 141, SUbpart S,
section. 141.11(b), 141.12, and 141.'1(a))
The substances arsenic, benzene, cadmium, lead, total
mercury, trichloroethylene, tetrachloroethylene, and total tri-
halomethanes have Safe Drinking Water Act (SDWA) Maximum
contaminant Levels (HCLs). These substances correspond to the
arsenic, benzene, cadmium, lead, mercury, trichloroethylene,
tetrachloroethylene, and chloroform detected in samples collected
at the site. These MCLs typically apply to public water systems
having at least lS service connections or serving an average of
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54
at least 25-year-round residents as well as to non-transient,
non-public water systems regularly se~ing at least 25 of the
same persons over six months per year. Because ground water
affected by the site is extracted by the wells of residents and
not a community system, the SDWA MCLs are not applicable.
However, they are relevant and appropriate requirement as in-situ
cleanup levels for ground water that is used for drinking water.
The alternatives that include provision of alternate water will
comply with the SDWA MCLs. Alternatives 2 and 4 will include the
provision of a municipal water supply line, which undergoes
routine testing to ensure compliance with MCLs.
Acceptable Intat.s Chronic (AICs) and Potency ractors (prs)
These are TBCs (to-be-considered) requirements that were
identified in the Public Health Evaluation Report as providing
the best available health standards for indicator chemicals
detected at the site. These criteria are detailed in Table
D for the contaminants of concern at the site. These standards
are the best available to ensure protectiveness of the remedy and
compliance with ARARs. Of specific concern at the site is the
inhalation pathway for potential exposure to contaminants.
Limiting access to the site, as provided in alternatives 2 and 3,
will potentially comply with inhalation TBC criteria by reducing
the potential for exposure to fugitive dust generati~n. These
alternatives would leave the onsite soils, sediments and solid
waste unaddressed, and thus they would remain as a source of
fugitive dust generated by the wind.
Alternatives 4 and 5 fully comply with this TBC though
capping the contaminant bearing media. These alternatives also
comply with the TBC criteria for the dermal contact and
incidental ingestion exposure routes, because the landfill cap
will prevent contact with the contaminants.
Municipal .aste XaDaq..ent\LaDdfill aequlation. for
Penn8ylvania
(25 PA Code Chapter 75)
These regulations pertain to the operating and applications
requirements for persons and municipalities that operate
municipal waste landfills in Pennsylvania. Chapter 75, Sections
75.21 through 75.38 of the Pa. Code of regulations establishes
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55
provisions for the managem~nt of municipal and residual waste.
These regulations are relevant and appropriate for the site
conditions, and may be considered applicable once additional
field work has been completed. While Mr. Barkman never received
a permit from the State for the operation of a municipal
landfill, upon completion of the field tasks required to properly
design a.landfill cap, we may find that only municipal and
construction wastes were disposed of at the site. If so, these
requirements will be ARARs, and the landfill cap will be designed
to comply with the State's requirements. Based on our knowledge
of past site operations, it is assumed that we will find mostly
municipal and construction debris within the landfill, and thus
this ROD calls for a landfill cap that meets the requirements of
the municipal waste management regulations.
Resource COD.ervatioD and Recovery Act - (40 CFR Part
264.J10(a), 264.117(c), 264.310(b»
The RCRA regulations pertaining to capping and closure with
waste in place are considered to be relevant and appropriate for.
the site conditions. These requirements are applicable if a RCRA
hazardous waste was placed at the site after November 8, 1986; or
if placement of a hazardous waste occurred in another unit when
the waste is being covered for the purpose of leaving it behind
after a remedy is completed. The Walsh Landfill operated from
1963 through 1976, and according to the site owner, strictly
junkyard activities occurred at the site from approximately 1976
to the present. State and EPA records do not indicate any
officia~ closure date for the landfill, and it is assumed that
during the history of site operations, a mixture of solid and
listed hazardous waste was disposed of on the site. since the
RI/FS did not include sampling of the landfill materials, we
presently have no documentation of the presence of RCRA hazardous
wastes within the landfill. During the design work required for
the landfill cap, sampling of the landfill will be completed.
The results of this work will be used to properly design a
landfill cap that is appropriate for the site conditions, and the
nature of the waste materials found therein. The land disposal
restriction. ("land ban") will not be an issue since placement of
wastes will not occur with this remedy.
In addition, associated requirements for operation and
maintenance (40 CFR 264.310) and Surface Water Control (40 CFR
264 .301(c) (d» will be relevant and appropriate for the landfill
capping action at the .site. These requirements may be considered
ARARs based on the findings of field investigation .ork required
to properly design the landfill cap.
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5'
Underground storag.- Tanka: Final Rul. (40 CFR Parts 280 and
281, Subpart E, Section 280.52(b), Subpart F, Sections 280.62(a),
280.63(a), and 280.64
The Underground Storage Tank program pertains to the
regulation of petroleum and hazardous substance storage tanks,
and includes- appropriate measures for leak detection, leak
prevention, corrective- action, and sampling and closure -
requirements. These requirements will be ARARs for the sampling
and removal of the underground petroleum tank present onsite.
Due to the presence of a gasoline pump adjacent to the onsite
garage, we have assumed that at least one underground petroleum
storage tank is present. The pre-design activities associated
with the implementation of the selected remedy will include-
confirming the tank's presence, and sampling the tank contents.
All activities associated with the onsite underground petroleum
storage tank will be completed in compliance with the UST
regulations. .
Schedule
The anticipated schedule is for the design to begin in the
late summer of 1990. Once the design is completed, a
construction period of three to four months will be required for
the extension of the water supply lines and service connections
to the individual homes. Construction of-the landfill cap and
the associated resource recovery activities are expected to last
from 18 to 24 months.
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57
TABLE E5-1
WELSH ROADfBARK)'IA~ LA~DnLLSlTE
Sl")'I)'IARY OF DETAILED EV ALl"ATION OF THE RE)'IED[AL ACTIO~ ALTERSATIVES
Evaluation Criteria RAA No.1 RAA No.2 RAANo.3 RAA No.4 RAA ~o. 5
OveraJl Protectiveness
of Human HeaJtb and
tbe Environment
Ingestion of Groundwater No risk reduction Protects againlt Partial protection Protects against Partial protection
by Residents existing risk by againat existing risk nisting risk by against nisting risk
providing alternate by providing bottled providing alternate by providing bottled
water supply water water supply water
.--------. ------- .------- -------. ------- --------
Ingestion of Groundwater No risk reduction No protection for No protection for Cap will reduce Cap will reduce
by Future lisers future uaers unlesa future users unle. leachate generation; leachate generation;
water supply system bottled water providing some providing some
is npanded distribution is protection to future protection to future
expanded users users
. ---- - _.- -. ~------ .------- -------. ------- --_._----
Protection from Dermal No risk reduction Alternate water Bottled water protec:t.l Alternate water Bottled water protects
ContactlInhalation Risb supply system againat current risb lupplYIYst.em against carrent risks
from Groundwater for protectl against posed by groundwater protect8 against posed by rroundwater
Residents uisting and potential ingestion: does not emting and potential ingestion: does not
future risu provide protection future risu provide protecti
against inhalation against inhalatio..
expo.ure pathway exposure pathway
--------- ------ -------- -------- ------- ~-------
Protection from Dermal No risk reduction No protection for' No protection for Cap will reduce Cap will reduce
ContactlInhalation Riaks future uaers uale.. future users leachate generation leachate generation
from Groundwater for water supply system providing some providing some
Future Residents is eltpanded protection. Water protection
supply "Item
upanaion will
provide additional
protection
~-------- ~------ -------- -------. ------- --------
Protection from Dermal No risk reductioD Feace .ill provide Fence will provide Cap will be protecti':e Cap will be protective
Contact/Ingestion of On- prot8cQon only u protection only.. ofbwaan health ofhwnan health
Site ContamUlated long u it ia long sa it is
',{ a terlaa maintained maintained
~-------_. ------ ~------- ------- ------- --------
Protection from Inhalation No riak reduction Fence will restrict Fence will restrict Cap will be protective Cap will be protective
oiOn-Site Contaminated vebicle acee.. anei vetUcle acee.. anei oC human health by ofhUtD&n health by
"{ a te rials reduce dU8t reduce dun eliminating dU8t eliminating dust
,eneration generation generation generation
-------- ------ ~------- -------- ------- ~-------
Environmental Protection Allowacontinued Allows continued Allowa continued Reduc.. leachate Reduces leacbate
contamination of contamination of the contamination of the generation althougb generation although
the groundwat.er rroundwater groundwater continued continued
coat..",i"."t contaminant
migration iaallowed migration is all,
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58
TABLE ES-(
(Continued)
WELSH ROADIBARK~A~ LA="iDnLL SITE
St;M~RY OF DETAILED EVALCATIOS OFTHE RE~EDIALACTIOS ALTER:-iATIVES
Evaluation Criteria RAA No.1 RAA ~o. 2 . RAANo.3 . RAA No.' ' RAA ="io. 5
Compliance witb
ARARs
Chemical-Specific ARARa None complied with Groundwater ARARa Groundwater ARARa Groundwater ARARs Groundwater ARARs
regarding human regarding human regarding human regarding human
health met; ones health partially met; health met; one8 health partially met;
regarding ODe8 regarding regarding ones regarding'
groundwater clean. up groUndwater clean-up groundwater clean-up groundwater clean-up
are not are not are partially are partiaUy
addressed addressed
~-------- ------ .------- -------. ------- --------
Location-Specific ARARa No location-specific No lacation-specific No location-specific No location-specific No location,specific
AMRa identified ARARa identified ARARs identified ARARa identified ARARs identified
~-------_. ------ .------- -------. ------- --------
Action-Specific ARARa No actioD-specific No action-specific No action-specific State ARARa RCRA ARARa
ARARa identified ARARa identified ARARs identified concerning capping concerning capping
complied with; ReRA complied with
AMRa will be
complied with
pending completion of ,
design
~------ ------ .------- -------. ------- --------r
TBC Criteria None complied with TBC. involving TBC. involviD, TBC. concerning TBC8 involving
ingesUon of ingeltion of ingestion and ingestion of
contaminanta met; contaaUnanta met; inhalation of contamiaantt met;, -
thoae involving those involvinc contaminantt are those involving
inhalation are inhalation are complied with inhalation are .'
partiaUy addre888cl pa.rt.i&11y addreued partially addressed
Long-Term
Effectiveness and
Permanence
"fagnitude ofResidua.1 Esiating riak will Current riak reduced Current risk due to Current risk i8 Current risk due to
Risks Posed by remain or eliminated., ingeltion i8 redw:eci: reduced or ingeatioD i8 reduced:
Groundwater potential future risk risu due to eliminated. Cap riau due to
pouibl. inhalation are not redw:ea potential inhalation are not
reduced - potent.ia1 future riak reduced. Cap reduces
future rilk due to poteotial future riSK
dermal contact or althoUCb future risk
iahalation i8 po88ible due to dermal contact
or inhalation is
poaaible
~-------_t ------ ~------- -------- ------- --------
~{agnitude of Reaidua.1 Esiltiag riak will Current riak i8 Current riak iI Current riak i8 Current ruk ia
Riak Posed by On-Site remain reduceci. pot.anuu redu.ced. poteoU.a1 eliminated. Future eliminated. Future
~-'''rial ruture riak i8 future risk i8 risk i8 reduced if cap riak is reduced Ii cap
controUed only if cootrolled only if i8 maintained. is maintained-
fence i8 maintained rence is malotained althouch wute wiU althouch waste will
remain 00 site remai.D on lite
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59
TABLE ES.l
iContinued>
WELSH ROADiBARK)1A~ LA~DnLL SITE
St")1)1ARY OF DETAILED EVALt:ATION OFTHE RE)fEDIALACTION ALTER~ATIVES
Evaluation Criteria RAA No.1 RAA :-lo. 2 RAA No.3 RAA :-lo. 4. RAA No.5
Adequacy and Reliability No controls Alternate water Bottled water is Alternate water Bottled water supply
of Controls considered supply is effective in effective in reducing supply is effective in is effective In
controlling risk from risk from controlling risk from reducing risk frolD
groundwater; fence is groundwater groundwater. Cap is groundwater
oflimited ingestion. but not effective in ingestion. but not
effectiveness inhalation; fence is of controlling risk from inhalation. Cap is
limited effectivenesa on-site material effective in
controlling nsk from
on-site material
~ - - _.- - - - - 11 ------ -------- -------. ------- --------
Five Year Reviews Five year reviews Five year reviews are Five year review. are Five year review. are Five year reviews are
are required required required' required required
Reduction of Toxicity.
Mobility. or Volume
Through Treatment
Treatment None used None uaed None uaed None uaed None used
---------. ~------ .------- -------. ------- ~-------
ResiduaJa from Treatment None None None None None
---------. ------ ~------- -------. ------- ~---_r' --
Statutory Preference for Not aati.s1ied Notsatimed Not aati.tieci Not aatiafied Not satisfied
Treatment
Short.Term
Errectivenes8
Community Protection RisU remaiD Community protected Community protected Community protected Community protected
unchanged from contaminated from contaminated from contaminated from contarrunat8d
groundwatet; on.lite groundwater ground)IVatat; on. lite groundwater
mataria1a remaiD ingestion, although materia1a remaiD ingestion. althougl1
undilturbed potential tbreata uadiaturbed potential chreata
posed by groundwater posed by groundwater
due to inhalation ant due to in.b&lation are
still preMaCO on-lite still present; on-site
mataria1a remain materials remain
undiaturbed undisturbed
--------- -------. .------- -------. ~------- ~-------
Worker Protection No t:ip.ificant riak No liCDific:ant risk to No significant riak to Worker protection Worker proteCUon
to workera work.1'8 workera required during cap required during cap
consU'W:tion constrUCtion
-------
60
TABLE ES.l
(Continued)
WELSH ROADiBARK:\1A:-t LA~DnLLSITE
St::\1~ARY OF DETAILED EV ALUATIO~ OFTHE RE:\1EDIALACnOS ALTERNATIVES
Evaluation Criteria RAA No. 1 RAA ~o. 2 RAA :-10.3 RAA ~o. 4 RAA ~o. 5
Implementability
Ability tD Construct and :-;0 construction or Conventional Conventional Conventional Conventional
Operate operation construction and construction and construction and . construction and
operation operation operation operation
~-------_. 1------- ~------- -------. - - -'- - - - --------
Ability tD ~fonitor Groundwater will ~onitDnng will MonitDring will ~onltDring will Monitoring will
Effectiveness be monitDred provide indication of provide indication of provide indication of provide indication of
an increase in an increase in' an increase in an increase in
groundwater groundwater groundwater gt'oundwater
contamination contamination contamination contamination
---------.. .------ ~------- -------. ------- ~-------
Approvals. Permits. None necessary Coordination with None necessary Coordination with None necessary
Coordination Honey Brook Borough Honey Brook BoroUlh
Water Authority and Water Authority and
Chester County Cheater County
Health Department Health Department
likely to be neceuary likely to be necessary
State Acceptance State acceptance to State acceptance to be State acceptance to be State acceptance to be State acceptance to be
be addreued in the addreued in the ROD addreued in the ROD addressed in the ROD addressed in the RO D
ROD
Community Acceptance Community Community Community Community Community
acceptance to be acceptance to be acceptance to be acceptance to be acceptance to be
addressed in the addreued in the ROD addreued in th. ROD addressed in the ROD addressed in the ROD
ROD
Estimated Time for .. 1 year 0.5 yean 2 to 2.5 yeara 1.5 to i years
Implementation of Design
and ConstrUction Phue.
Cost ($).
Capital Cost 289.000 1.328.000 328.000 2.775.000 2.312.000
---------. ~-----_. ------- -------. ------- --------
Annual Operation and 32.000 57.000 50.000 63.000 55.000
~aintenance Cost
--------- ------- .------- -------. ------- ~-------
Operation and 228.000 103.000 245.000 109.000 251.000
'.faintenance Cost Durin,
Fi ve. Year Reviewl
---------- 1-------- -------- -------.. 1-------- ~-------
Present Worth Colt 1.258.000 2.242.000 1.538.000 3.768.000 3.601.000
-------- 1--_____4 -------- -------.. ~------- ~-------
Worst-Cue Present Value 1.886.000 3.026.000 2.208.000 4.970.000 4.623.000
---______4 1------- .------- -------. 1-------- ~-------
Belt.Cue Present Value 825.000 1.866.000 992.000 3.180.000 3.002.000
.~ costa are rounded to Uze nearest $ 1.000.00.
-------
WELSH ROADiBAHKMAN LANDFILL SIT~
HONEYBROOK TOWNSHIP, PE:--lNSYLV ANIA
RESPONSIVENESS SUMMARY
JUNE 1990
This Responsiveness Summary documents public concerns and comments expressed during
the public comment period. The summary also provides EPA's and PADER's responses to
those comments. The information is organized as follows:
1. Overview
2. Summary of Community Involvement
3. Summary of Comments Received During the Public Comment Period and Agency
Responses
4.
Responses to Potentially Responsible Party's Comments
1.0
OVERVIEW
The public comment period for the Walsh Landfill Site (a.k.a. Welsh Road/Barkman Landfill
Site) began on March 18, 1990 and extended until May 18. 1990. To facilitate commenting,
EPA and PADER held a public meeting at the Honey Brook I"ire Hall on March 27,1990.
At the meeting, EPA and PADER discussed the Remedial Investigation (RO. I"easibility Stud)'
(FS) and Public Health Evaluation Reports performed for the site and presented the Proposed
Plan for eliminating/mitigating public health and environmental threats posed by
contamination detected in environmental media in the area. EPA explained that the plan.
addresses the first Operable Unit (OU), which consists of replacing contaminated potable
water supplies and proper closure of the landfill; a plan for addressing the second au.
contaminated groundwater, will be developed after a forthcoming areawide groundwate.r
study is completed. The preferred remedial action alternati ve for the first OU involves
extending a municipal waterline to service affected residences, constructing a multi-media cap
over the landfill and implementing land use/access restrictions on the property of concern.
Local residents and officials offered minimal objections to the proposed plan; some public
meeting attendees did express preference to excavation and off-site disposal of the landfill
contents. The majority of concerns dealt with administrative issues regarding the service area
of the proposed waterline extension, payment oC water bills, well abandonment procedures and
deed restriction issues. Technical concerns 'focussed primarily on possible effects on the
current municipal water supply by contaminated groundwater detected in the vicinity of the
site. Also, during the public meeting a number of local residents expressed serious concerns
regarding ongoing operations being conducted at, and in the general area of, the Welsh
Road/Barkman Landfill Site. However, this Responsivenes8 Summary is limited to those
comments in the proposed remedial action plan and any other portion oC the Administrative
Record detailing the Welsh RoadlBarkman Landfill NPL Site. Current site operations are not
addressed as they are within the realm of local and state enforcement concerns.
-------
2.0
SUMMARY OF COMMUNITY INVOLVEMENT
Community relations activities associated with the Welsh Road,. Barkman Landfill Site were
initiated by PADER in 1979. PADER served as the lead response agency during the sampling
of residential wells that occurred from 1979 through 1989. Throughout the duration of the
well sampling program and site investigation (Rl/FSJ, the State maintained contact with
residents from approximately 43 to 49 homes in the site area. The State forwarded
correspondence with sampling results to the residents during this period, and updated
interested citizens, local government officials and the site owner on the status and findings of
the RIIFS.
On February 16, 1990, EPA and PADER placed the Administrative Record in a repository
located in the Honey Brook Library, Honey Brook, PA. On ~arch 18, 1990, EPA and PADER
placed a quarter page advertisement in the West Chester Daily Local and the Lancaster ~ew
Era, announcing the 30.day comment period on the Proposed Plan for the first operable unit of
the Welsh Road/Barkman Landfill Site. Also announced was the availability of the Proposed
Plan. Rl/FS. and Public Health Evaluation reports. as part of the Administrative Record in the
site repository.
The public comment period began March 18, 1990, and ended ~1ay 18, 1990. EPA received a
timely request for an extension of the comment period. and thus granted the minimum 30-day
extension, in accordance with the revised provisions of the National Contingency Plan (NCP).
A public meeting was conducted on March 27,1990 as was described previously in Section 1.0.
3.0
SUMMARY OF COMMENTS RECEIVED DURING THE PUBLIC COMMENT
PERIOD AND AGENCY RESPONSES
Comments provided during the Welsh Road/Barkman Landfill Site public comment period on
the Remedial InvestigationlFeasibility Study, Public Health Evaluation and Proposed Plan
are summarized briefly as follows. The comment period extended from March 18 to May 18,
1990. The comments are categorized by relevant topic.
Remedial Action Preferences
1.
Several commenters expressed a preference for excavation of the landfill contents and
off-site disposal, rather than constructing a cap over the landfill. Their concerns were
related to the potential for the landfill to continue to serve as a source of contamination
even after the remedial action is implemented.
A2enCY Response: Excavation and off-site disposal was considered and evaluated as
part of the Feasibility Study. However, it was judged to be too costly, difficult to
implement given the undefined nature of the landfill contents and to have the
potential to expose local residents to unacceptable health risks during
implementauon.. .Furthermore, under the Superfund Amendments and
Reauthorization Act (SARA), this alternative is considered undesirable since it merely
transfers contaminated materials rather than reducing the mobility or toxicity of
hazardous wastes.
2.
One commenter asked if consideration is being given to pumping and treating
groundwater from residential wells to alleviate the potential for contaminating the
Honey Brook Borough Water Authority's municipal wellfield.
A2ency Response: Possible options for dealing with contaminated groundwater will be
considered under the second OU. A groundwater study of the area will be
2
-------
implemented and the results will be evaluated, with the focus on developing a cost-
effective remedial action for renovating contaminated groundwater.
3. One commenter inquired whether individual home treatment units were considered
instead of extending the waterline or supplying bottled water.
Agency Response: Yes, individual units were considered, but were rejected because
each unit would have to be routinely monitored to ensure it was performine
adequately. The frequency of these monitoring activities could not be defined since the
levels and types of contaminants varies considerably at each residence and also
because it would depend on the usage rate of each resident. Thus, there would be an
ongoing concern that the treatment systems were not performing as intended.
Administrative Concerns Regarding Remedial Alternatives
1. A number of questions were raised about the extension of the Honey Brook Borough
Water Authority waterline. Specifically, residents asked who would be responsible for
paying for water used once the hookups to the municipal supply were completed, who
would be provided with hookups and has EPA and the Honey Brook Borough Water
Authority signed an agreement to implement this option?
Agency Response: Once each hookup has been completed, the individual residents will
be responsible for paying for water used, just as the current customers must pay for
water. No final decision has been reached on specific residences to be included as part
of the waterline extension. This determination will be based on the results of the
upcoming groundwater study, which will focus on better defining the extent of
contamination and the rate and direction of contaminated groundwater flow. Those
residences affected or anticipated to be affected before groundwater remediation is
completed in the area will be provided with hookups to the waterline extension.
Honey Brook Borough Water Authority has been consulted regarding extension of the
waterline and will continue to have input during the design and implementation of
this portion of the remedial action. However, no agreement has been signed to date
with the Authority since the waterline extension is only proposed at this time.
2. Residents were concerned about residual contamination that may exist in their
plumbing and fixtures and what steps are necessary to ensure that municipal water is
not contaminated by residual contamination.
Agency Response: No special precautions other than thoroughly flushing the lines
initially is all that will be necessary since the contaminants of concern do not have a
strong affinity for accumulating within the plumbing or fixtures.
3. The question was raised regarding providing hookups from the extended waterline to
undeveloped properties. Also, a concern was expressed about the area losing its rural
flavor if the municipal water supply is extended into the area.
Agency Response: It is EPA's policy under the Comprehensive Environmental
Response, Compensation and Liability Act (CERCLA) not to encourage development
as a result of implementing a remedial action. Therefore, undeveloped properties will
not receive a connection to the waterline. However, this does not prevent future
connections if the local authorities permit such an occurrence and the landowner pays
for the connection.
development.-HQweVirVjtneTlocaI'mfinTclDalitlesTjave expressed°a desire co
maintain low density development in tne site area;
-------
4. Several commentators asked if farms will be connected to the waterline and will
sufficient water be provided to water livestock and allow irrigation activities to be
conducted.
Agency Response: Farms will be provided with the same connections as other
residences (i.e., for domestic consumption). Ponds located on one of the farms were
sampled and the results indicated that the water was not contaminated, so their use of
the ponds to water livestock and to irrigate can continue. Depending on local water
authority policy regarding well abandonment, groundwater from existing wells may
continue to be used for nonpotable purposes such as irrigation.
5. One commenter reported that he cannot develop his property because he is unable to
obtain a well drilling permit from the Chester County Health Department reportedly
due to the problem at the Welsh Road/Barkman Landfill Site. If bottled water is the
selected option and wells are prohibited in the area, will he be supplied with bottled
water if he develops his land?
Agency Response: EPA and PADER do not have authority to interfere with Chester
County Health Department policy regarding issuance of well permits. Since bottled
water is not the preferred alternative, determination of who will receive bottled water
has not been made. However, as stated previously, CERCLA policy is not to encourage
growth in an area, so properties not developed at the time of remedial action
implementation likely will not be eligible for bottled water.
6. Numerous questions and opinions were expressed in regard to possible abandonment
of existing wells once the waterline is extended and hookups are provided to this new
supply. Both positive and negative statements on the issue of mandatory well
abandonment were made during the public meeting. Commentators in favor of
mandatory well abandonment were concerned about possible contamination of the
municipal water supply from contaminated groundwater and the possibility that
continued pumping of local domestic wells may accelerate migration of contaminated
groundwater to unaffected areas. Negative responses focused on the additional
expenses that would be incurred by homeowners who paid to have wells installed and
now would be unable to use them even for nonconsumptive purposes (laundry,
washing cars, watering lawns, etc.).
Agency Response: EPA and PADER do not have the authority to institute an
mandatory well abandonment policy. This requirement likely would be a condition
imposed by the Honey Brook Borough Water Authority to protect the municipal
supply. However, EPA and PADER would encourage the Authority to require proper
well abandonment aa a sound public health measure. Also, it is possible that
continued pumping may further spread groundwater contamination to areas not
previously affected.
7 The issue of deed restrictions was addressed by several commentators. The concern
was expressed that mandatory deed restrictions could have an adverse impact on
property values. Also, a commenter asked what the wording of the deed restrictions
would be.
Agency Response: Mandatory deed restrictions would be confined to the property(ies)
on which the landfill cap is placed to prevent disturbance of the cover and to advise any
future landowner of the presence of the landfill. Voluntary deed restrictions could be
placed on surrounding properties advising future purchasers of the possibility of
contaminated groundwater underlying affected parcels. The exact wording of the
-------
mandatory deed restrictions has not yet been developed, but will be in accordance with
:;tate and local requirements for landfills containing hazardous materials/wastes.
Wording for voluntary deed restrictions will be at the discretion of the current
landowners.
Commentators at the public meeting were concerned about declining property values
and difficulties experienced in selling homes in the area. Their question basically
centered on what relief could be provided under CERCLA.
A/Zency Resoonse: Although EPA and PADER sympathizes with local residents, there
are no regulatory provisions for monetary compensation for diminished property
values or reduced salability of h.omes under CERCLA. However, there may be legal
remedies available to affected residents. EPA and PADER suggest those who believe
that they have suffered economic losses consult their attorneys for possible relief
through the courts.
Several people at the public meeting asked who would own the site once remediation
was completed and who would prevent future occurrences like the ones that initiated
the problems at this site.
A/Zency Response: Technically, the current property owner would continue to own the
land once the remedial actions have been completed. Future incidents can be avoided
by local and state agencies maintaining enforcement of existing laws and ordinances.
One commenter asked what options were available to local residents who had
consumed contaminated groundwater and experience adverse health effects.
)
A/Zency Resoonse: EPA and PADER suggest consulting an attorney to determine
what legal recourses exist for residents that believe they have site-related health
effects.
. ..,.hnical Questions/Concerns Regarding Remedial Alternatives
Several questions were raised regarding the landfill cap. These concerns included the
purpose of the cap, runoff controls to be provided to prevent adverse off-site effects and
responsibilities for maintaining the cover.
A/Zency Resoonse: The purpose of the cap is to reduce/eliminate percolation of
precipitation through wastes contained in the landfill, thereby limiting the amount of
leachate generated. The cap will be designed to promote posit.ive drainage and prevent
ponding of water on the surface of the landfill, which also will reduce generation of
leachate. The design of the cap will include control of surface runoff and erosion to
minimize potent.ial of adverse ofT-site effects to adjacent properties. Maintenance of
the cap and associated facilities initially will be assumed by EPA; continued
maintenance will be provided by the State.
An attorney represent.ing several adjacent landowners asked what. health risks were
associated with impleme"tation oft.he alternative presented in the Proposed Plan.
Allency Resoonse: The remedial action alternative presented in the Proposed Plan is
intended to prevent the health risks identified at the site by eliminating the link
between receptors (i.e., the local residents) and contaminated environmental media
(Le., surface soil. and groundwater). The links, or pathways, that currently exist
include direct contact with contaminated soil and groundwater, ingestion of soil and
5
-------
groundwater and inhalation of these media. The remedial action would prevent direct
contact by covering contaminated soils and eliminate ingestion or inhalation of
contaminants by providing an alternate water source for drinking, cooking and
bathing/showering.
3 Numerous comments during the public meeting addressed the effects that the site was
having on the existing municipal wellfield and the current quality of the municipal
supply (i.e., is the present source safe to drink?).
Agency Response: There is no evidence of any near term impact on the Honey Brook
Borough Water Authority's water supply from contamination originating from the
site. The municipal supply is regulated under the Safe Drinking Water Act (SDWA)
and is routinely sampled and tested to ensure compliance with all applicable drinking
water regulations. EPA will be conducting an areawide groundwater study to
determine the rate and direction of contaminated groundwater migration off site and
will advise residents of the findings as soon as they are available. A major focus of this
study will be to determine if the municipal supply is threatened and what steps must
be taken to prevent degradation of the municipal supply.
4. On a related issue, the question was raised regarding the direction of groundwater
flow in the vicinity of the site and the effects of local quarrying operations on flow
conditions.
Agency Response: Groundwater flow in this area is complex due to existence of
varying geologic features underlying the site. The forthcoming groundwater study
will be designed to better characterize the hydrogeologic setting so that an accurate
portrayal of groundwater conditions can be developed and appropriate measures
implemented to remediate groundwater in the area. Currently, it appears that in
general, groundwater in the vicinity of the site flows from the northwest to southeast,
following the topography of the area. Any effects caused by blasting at local quarries
have not been documented presently, but will be examined as part of the groundwater
study.
5. Questions arose about the time to implement the measures outlined in the Proposed
Plan.
Agency Response: EPA hopes to extend the waterline and provide connections to
affected residents within one year of signing of the Record of Decision. The
groundwater study would be conducted concurrently with design of the waterline
extension to determine what residents will be included in the service area. Overall,
the remedial action is estimated to require 24 to 36 months to implement from the time
that the Record of Decision is signed and a contractor is selected to initiate final design
of the action.
6. Several commentators asked about the residential well sampling program.
Specifically, residents wondered how homes were selected for sampling and how far
along Quarry Road were residences sampled?
Agency Response: Several rounds of residential well sampling have been conducted by
PADCR in past years. Attempts were made to include all homes in the general vicinity
of the site. Many times repeated attempts were made with local homeowners to
sample on specific dates, but due to varying reasons these contacts were unsuccessful.
In general, most of the homes believed to be affected were sampled and the residents
provided with the results. The upcoming groundwater study also will include another
-------
8.
9.
round of residential well sampling and local residents will be contacted rt:garding
specific dates that sampling activities will be performed.
-
, .
One commenter expressed concern regarding the groundwater 5tudy and the potential
for the installation of additional monitoring wells to introduce contaminants into
currently unaffected aquifers, most notably the lIoney Brook Borough Water
Authority wellfield aquifer.
Agencv Response: Installation of additional wells likely will be necessary to
adequately characterize groundwater conditions in the area. Every etTort will be made
to drill and install wells in an environmentally safe manner, thereby minimizing the
potential for introducing cO'ntaminants into any unatTected aquifer in the area.
The question was raised about the potential for the ongoing operation to continue to
affect groundwater and other environmental media in the area. Of primary concern i5
the possible etTects of contaminants (gasoline, oils, lubricants, antifreeze, etc.) from the
large number of automobiles currently present onsite. Also, even if these vehicles are
moved to another location, won't they still pose a threat to the environment?
Ag-ency RespOnse: Yes, it is likely that contaminants typically associated with
abandoned vehicles such as gas and oil could be adversely affecting groundwater.
During the remediation vehicles located in the area to be capped will have to be
removed before the cap is installed. EPA and PADER recognize that simply moving.
the vehicles will not eliminate the problem of continued contributions to groundwater
contamination. However, it will be the responsibility of state and local agencies to
enforce zoning codes and laws governing any ongoing operations that are outside of the
areas to be remediated under the Proposed Plan.
I
"
The question arose regarding sampling of the contents of the landfill during the
Remedial Investigation. In addition it was noted that a discrepancy was reported in
the local newspaper about the size of the landfill (property was reported to be 8 acre5,
landfill cap size in the Feasibility Study is 5.2 acres).
Ag-ency RespOnse: Sampling of the landfill contents was not performed during the
Remedial Investigation due to a number of factors including the inability to gain
access to most of the landfill surface because of the extensive amount of junked
vehicles, appliances and other materials covering most of the area. However, before
final design of the landfill cover proceeds, a predesign Investigation will be conducted.
This investigation will include sampling of the landfill contents to better define the
types of wastes contained therein and the extent of the . landfill (i.e., how much of the
property actually comprises the landfill verses areas that contain junked vehicles and
other materials, but are not underlain by landfilled materia!::;\' .
I U.
One commenter noted that the Proposed Plan calls for a 120,OOO-gallon storage tank
as part of the alternate water supply and inquired as to whether this would be
sufficient to handle peak demand for the residents to be served.
Ag-ency Response: The alternate water supply system described in the Proposed Plan
represents the initial engineering estimate and is based on preliminary calculations
for sizing the storage tank. During the linal design stage, when the number of homes
to be serviced is determined, peak demand requirements will be recalculated and the
size of the storage tank revised as necessary.
7
-------
11.
The question of whether it is ::iafe to grow foud in the gTound uverlying cont
-------
2.
Several people inquired as to why the ::iituation at the site has been allo~ed to conunuc
for so many years apparently without attempts by enfurcement agenci!:s to correct
and/or cease disposal operatiuns.
Al!ency Response: PADER has undertaken a number of enfurcement actions over the
years, but has been unsuccessful in persuading the property owner to conduct
operations in accordance with environmental regulations either voluntarilv ur
through legal action. Such enforcement actions will continue to be pursued ei"ther
through negotiations or via the courts.
3.
During the public meeting a number of people expressed concerns about other possible
operations in the area that may be contaminating the environment.
Al!ency Response: State enforcement officials requested that suspected polluters be
reported to them and that appropriate foHowup actions will be taken.
4.0
RESPONSES TO POTENTIALLY RESPONSIBLE PARTY'S COM MENTS
The following are paraphrased comments and agency responses to the May 18, 1990 letter
from Mr. Stephen W. Miller, Attorney, with Clark, Ladner, Fortenbaugh & Young
representing Mr. Ernest Barkman, owner of the Welsh Road/Barkman Landfill on the
~ational Priority List (NPL) in Honey Brook Township, Chester County.
1.
EPA and PADER have not formally requested comments on the Public Health
Evaluat.ion Report.
Agency Response: Contrary to this comment, the Environmental Protection Agency
(EPA) and Pennsylvania Department of Environmental Resources (DER) have invited
comment on the Administrative Record, as well as the Proposed Plan. Included in the
Administrative Record is the "Final Public Health Evaluation - Welsh RoadlBarkman
Landfill Superfund Site, Chester County, Pennsylvania" prepared by BakerrrSA, Inc.,
dated January 1990, (Public Health Evaluationl. This Public Health Evaluation
replaces Chapter 6, Risk Assessment, in the "Remedial Investigation Report for the
Welsh RoadlBarkman Landfill Site,. Honey Brook, Pennsylvania" prepared by S~tC
~tartin, Inc., dated December 8, 1988 (RII. Also replaced by the Public Health
Evaluation are any conclusions which were developed in the RI, based on the previous
Risk Assessment in Chapter 6. As work began on the Feasibility Study it became
evident that the Risk Assessment did not address all of the exposure pathways and
exposure receptors, as required by the EPA guidance documents. A thorough Public
Health Evaluation, following EPA guidance, was necessarily conducted by BakerrrSA
in order to appropriately define the remedial action objectives, a preliminary stage in
the development of Remedial Action Alternatives. The Public Health Evaluation was
developed using samples collected during the RI. but it was also supplemented with
data collected by PADER during April/May 1989. This Public Health Evaluation was
the decision-making document used for the purpose of evaluating human health risk,
and conclusions of this Public Health Evaluation assert that there is a significant risk
to human health posed by soils and groundwater in the vicinity of the Welsh
Ruad/Barkman Landfill SPL Site. The preliminary risks posed by the site are throu~h
contaminated drinking water supply, and the landfill soils and sediments. The
primary routes of exposure are through dermal contact, inhalation and ingestion of
either the soils or groundwater. .
9
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2.
Based on results of the RI, the site does not pose risks to public health or the
environment and, therefore, the site should be removed from the :'-iational Priorities
Ljst(~PLJ. .
A"ency Response: The results of the investigation and conclusions from the Public
Health Evaluation do reach the conclusion that there is a significant threat to human
health. As stated in 1. above, the Public lIealth Evaluation was used for the decision
making. The listing ofthi::; site on the ~ational Priorities List ":'IlPL" was based on the
Hazardous Ranking Score available in EP A's docket.. The RI was not used to list. the
site on the NPL.
3.
Previous PADER inspect.ions indicate that the landfill was used solely to dispose of
municipal and residential refuse and currently the propert.y is operating as a licensed
junkyard.
AlO1;ency Response: The comments neglect to mention that the inspect.ion reports
document numerous violat.ions of the PA Solid Waste Management Act, for which
fines were levied against Mr. Barkman for unacceptable landfill practices.
Additionally, in 1973, criminal charges were filed against Mr. Barkman by DER, with
respect. to operat.ing a waste facility without. a permit, and for t.he burning of solid
wast.e at the site. In 1976, the Department requested that Mr. Barkman file a closure
plan, and properly cover the site in accordance with State Regulations. The closure
plan was approved in December 1976; however, Mr: Barkman has failed to properly
close the site, and landfilling practices have continued at the site to date. Further
inspections after 1977 by EPA and DER document the presence of hazardous
substances on site. Observations of these substances were evident during drum
sampling on site, as well as during the sampling of resident.ial and monitoring wells in
the site vicinity.
Mr. Barkman has never been issued a permit for landfilling at. t.he Welsh
Road/Barkman NPL Site. The junkyard license issued by Pennsylvania Department
of Transportation (PADOT) is for visual purposes, and requires primarily that a visual
barrier be maintained between the junkyard and Pennsylvania's highways. The
license is not. an authorization to violate state and federal environmental laws, and
Mr. Barkman has continued to violate the PA Solid Waste Management Act and
Federal Air Quality Regulations..
4.
No documented evidence was present.ed in the RI to indicate that hazardous
substances as defined under CERCLA have been disposed of at the site, nor has any
funding been presented that supports the allegation that a "release" of hazardous
substances has occurred at the site.
A2enCy ResDOnse: Numerous inspections were conducted at the site through the early
1980& by the Chester County Health Department, PADER and the Federal EPA. As
part of these investigations, monitoring wells were installed around the landfill by
DER and sampling was conducted on t.hese wells. The comparison of sampling data
from residential and monitoring wells shows that contaminants present in the wells
were and still are in the higher concentration at the toe of and near the landfill, and
decrease in concentration with distance from t.he landfill. Further, the 1984 sampling
of drums on site indicate the presence of toluene, ethylbenzene, 1,I-dichloropropane,
chlorobenzene and methylene chloride and provided evidence that Mr. Barkman was
cont.inuing to handle hazardous materials on site, without a permit. Based on these
observations, the landfill was indicated to be providing the source for groundwater
10
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degradation in the vicinity of the site, and the site ""-(1S placed on the :-..; PL list in
September 1984.
5.
. The RI sampling plan was deficient in that no sampling of the contents of the landfill
was conducted. This is in direct contradiction to investigatory procedures outlined in
the NCP.
A£ency Resoonse: The NCP does not direct EPA on where to collect discrete samples.
In numerous sites it is not the accepted procedure to sample through the landli II
material due to the possibility of introducing another now path for the conlaminants
to migrate through the waste material into the .underlying natural environment.
There is the additional complication of Barkman having an ongoing junkyard
operation on the site. The task of the RI was to characterize the landfill, not the
junkyard. Also, Mr. Barkman did not agree to allow sampling on the property until an
access order was obtained. .
Appropriate procedures and techniques were used in developing and carrying out the
sampling and analysis for soils, sediments, surface water and groundwater while
investigating the site for the RI. Groundwater monitoring wells were located based on
review of existing hydrogeologic data, aerial photography evaluation, fracture trace
analysis, and field accessibility in order to locate downgradient locations as well as
provide an off-site location not influenced by the site for comparison. Similarly
standard procedures were used to locate appropriate sample locations for sediment and
soil samples.
Direct sampling of the landfill materials will be completed during the design of the
landfill cap. Such sampling and analysis is typically deferred until remedial design
due to health and safety considerations for the nearby residents. The additional
complication induced by Barkman's current junkyard operation on top of and beyond
the landfill served to defer this direct sampling to the design phase.
6.
The RI field studies failed to delineate the landfill's actual boundaries as directed by
the NCP. .
Allencv ResDOnses: The RI served to assess the physical characteristics of the site;
however, an accurate definition of the landfill boundaries was deferred until remedial
design, due once a,ain to the complication posed by the.junkyard activities. Proper
closure oC the landfill was never completed by Mr. Barkman; therefore, the landfill
proper has continued to expand in size. Mr. Barkman has proceeded to operate his
junkyard cont.icuoua with and on top of the previously existing landfill, thus making
the limits of the landfill difficult to define. The size' of the debris, wast'e and
C088b'u.ction material on site has continued to grow even during the time of the RI.
C8INn1operationa attest to the fact that the landfill operations have continued to date
"therefore, the landfill boundaries have continued to expand.
Two drawin,s attached to Mr. Miller's comments dated 1981 and 1985 show the
landfill as a portion of the property. The second drawing, 1985, shows the location of
seep and drums sampled were outside the area designated by the preliminary site 1981
map as the landfill. The preparation of those ske~h maps was not done with the
availability oC accurate site topographic mapping. The limits of the landfill shown
were determined by a short field visit in 1981. Mr. Barkman has continued to conduct
all sorts of disposal, burning and junkyard activities on this and adjacent property.
Upon the supposed ceasing of landfill operation in 1976, junkyard acti vities began and
continue to the present. .
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7.
8.
9.
10.
The continuous movement 'of materials on the property and adjacent properties
prevent accurate measurement. The 5.2 acres used for the cost estimate are from what
appeared to be the landfill area regardless of the junkyard material as of July 1989
when the consultant, BakerfrSA conducted a field investigation for the "Feasibility
Study Report for the Welsh Road/Barkman Landtill Site" prepared by BakerfT'SA, Inc.
This area was based on best engineering judgment to prepare an adequate,
conservative cost estimate. The 5.2 acres was established to develop costs for
comparison of the different alternatives. An accurate landfill delineation based on
topographic mapping and sampling of the landfill material will be completed during
the design phase.
Groundwater now characteristics have not been adequately defined to date and
several wells, including site monitoring wells that showed contamination are
hydraulically upgradient from the landfill.
Ae:encv Response: The Groundwater Unit will be further investigated during the
Second Operable unit (OU). Data gaps in the groundwater.sections will be addressed
in the Second Operable Unit and subsequent studies..
The locations of the monitoring wells for this RI were selected for numerous reasons.
MW -1 should be a logical place for a monitoring well considering contamination had
been detected in a residential well, No. 23, near the location of MW -1. The presence of
pumping well, such as a residential well, can induce the movement of contaminated
groundwater toward the well. This can direct groundwater movement in a direction
different than the naturally occurring groundwater now.
The RI fails to adequately explain the rationale for the selection of the background soil
sampling location (58-1).
Ae:encv Response: The location ofSS-l is logical location for a background soil sample.
A background sample is typically located in an area off site that is not directly
influenced by site conditions (in this case the landfill material and the junkyardl.
None of the soil samples collected during the Rl can be related to specific areas of the
landfill since the RI did not delineate landfill boundaries.
Ae:encv Resoonse: The RI soil samples locations were selected in areas chosen to
represent or define the extent of contamination as best as could be done with the debris
and junkyard materials on the site. The conditions on Barkman's property at the time
of RI sampling can no longer be observed due to significant changes as a result of
ongoing operation of thejunkyard. Also, Mr. Barkman was opposed to any sampling
on his property. An access order was necessary to obtain access to his property.
The locations of the surface water and sediment samples collected during the RI are
not representative of conditions on or in the landfill.
Ae:ency Resoonse: Surface water and sediment samples were taken in areas were
surface water and sediments existed. [t is standard procedure to sample up and
downgradient for comparison purposes and to define the extent of contamination and
evaluate impacted media for remedial screening and selection. Location of the surface
water and sediment samples are site specific, and they are determined by the physical
characteristics that exist at the site at the time of the sampling (i.e.. visual evidence of
contamination, drainage paths that exist at the time of the sampling).
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12.
13.
14.
11.
The commenter questioned the validity of the RI monitoring well locations to
represent groundwater contamination emanating from the landfill.
A~ency Response: It is standard procedure to locate monitoring wells in areas
upgradient or off site not influenced by .the site and downgradient from a
contamination source. Upgradient wells generally characterize the uncontaminated
aquifer. Downgradient wells are used to evaluate migration of contaminants
(concentration and flow rates) for the purpose of assessing risks and screening
remedial alternati ves. Additional wells are then placed in order to assist in evaluation
of groundwater extraction and treatment as a cleanup method, when appropriate. The
selection of locations for the monitoring wells for this site used proper hydrogeologic
procedures and techniques such as aerial photo interpretation, fracture trace analysis,
and available geologic information of the site before the monitoring wells were
installed.
As discussed previously, monitoring wells are not usually constructed through landfill
materials because of health and safety considerations (drillers and nearby residents).
The RIfFS goal is to define and evaluate the problems existing in the contaminated
media, the groundwater, surface water, sediments and soils to consider cleanup
approaches.
The second OU will expand on the information and data generated during this RI and
will then define the full extent -of the groundwater contamination and screen
alternatives to address the groundwater contamination. -
The RI Risk Assessment states that risks to human health and the environment are
negligible and thus no remedy is required.
A~ency Response: As discussed earlier in I., the Risk Assessment used for this site
was the Public Health Evaluation conducted by Bakerfl'SA. Baker's work meets EPA
requirements and was used for decision-making purposes during the FS, for the
development of the Remedial Action Objectives.
The RI results for metals were interpreted improperly and inconsistently because
values that were within the normal range for uncontaminated soils were considered as
"contaminants" while other metals exceeding background were not addressed.
Allencv Resoonae: The metals detected in the soils. arsenic, chromium, copper, lead
and zinc were elevated with respect to background and regional soil concentrations.
The levels detected for the metals listed as contaminants were shown to pose an
tI~table health risk in Baker's Public Health Evaluation at the levels detected.
A8Ia refer back to 5. for the discussion on sampling. The elevated metals on
~'8 property also were detected ofT site., Generally, the samples close to the
~y and landfill had high metal concentrations, while samples collected at
distance (rom the site had lower concentrations. This shows a pattern of contaminants
occurring near the site. -
The occurrence of organic compounds in area groundwater cannot be attributed to the
landfill since no sampling of the landfill contents has been performed, nor have the
landfill boundaries been established in order to construct a cap.
Allencv Response: The landfill is logically the source of the area groundwater
contamination, since wells located in the proximity and downgradient o( the landfill
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15.
16.
17.
18.
19.
20.
dre more highly contaminated than tno::it: I'Jcated di::itant from the landfill. It is iuglCd!
to identify the only operation in the area as the source of the contamination. There
were drums found on site and the residential wells samples showed similar chemical
characteristics The RI adequately defined the landfill as the source of contamination
The landfill contents will be additionally characterized during the remedial design
The hydraulic relationship is to be fully defined during the work on the Second 01.:
Cap construction will be in accordance with results of the data obtained during site
characterization. .
~o discernible plume of groundwater contamination has been defined, with only
infrequent detection of contaminants documented at many of the residential wells.
AE!ency Response: Pumping of the local residential wells has an efTect on the natural
groundwater movement. The residential wells draw groundwater from various
directions. The contaminated water moves toward the wells as pumping takes place.
The Second Operable Unit as discussed above will further define the groundwater
environment and the limits of contamination.
The FS did not further define conditions at the site and ignored the RI Risk
Assessment findings.
AE!ency Response: The FS is not done to independently assess the landfill. The FS
screens the Remedial Alternatives based on the RI data and the Risk Assessment,
(Public Health Evaluation>. Baker's Public Health Evaluation determined
unacceptable risks posed by the ingestion of, inhalation of, and dermal contact with
contaminated landfill soils, and risks posed by the ingestion and/or inhalation of
contaminated groundwater.
The FS arbitrarily assumed an acreage of 5.2 for the landfill boundaries without
sufficient information to make this judgment.
AE!ency Response: Refer to the determination of the acreage of the landfill discussion
in 6. As stated before, the 5.2 acres was an estimate for costing alternatives. This
estimate was based on best engineering judgment during a field investigation July
1989. During the design phase the landfill will be defined and the estimate revised
accordingly. Mr. Barkman's continuing disruption of the site with salvage material
and other debris causes uncertainty as to the landfill size.
The FS confirms that no sampling of the landfill wastes has been conducted.
A2encv Resoonse: As discussed above in 5., sampling of on-site waste will be done
during the design phase.
The FS does not integrate information from the RI report as required by the NCP.
AlZencv Resoonse: The FS was done based on results from the RI sampling and data
gathering. The Public Health Evaluation was done using results from the RI sampling
and data gathering. Therefore, the FS is integrated with the site characterization.
The FS emphasizes the concern that groundwater in the area has not been adequate I)'
characterized.
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21.
22.
23.
24.
25.
Allency Response: As stated previously, the groundwater flow and limits vI'
groundwater contamination will be more accurately defined when additional data are
gathered during the Second Operable: Unit investigation.
The FS discusses potential risks to receptor populations rather than actual risks and,
does not provide a water balance to indicate the potential of the landfill to generate
leachate.
Allency Response: The RI showed the presence of elevated levels of hazardous
substances. The Public Health Evaluation showed that these levels pose an
unacceptable risk to receptors by several pathways. The selection of the Remedial
Action Alternative is based on protecting against existing and potential risks in
accordance with EPA guidance. The immediate threat of residential well
contamination was addressed by rapid response (i.e., bottled water). The remedy
selection through the FS process screens 'alternatives for long-term etTectiveness. This
pertains to the protectiveness of the remedy for both actual and potential future
problems. The second Operable Unit (OU) or groundwater study will evaluate the
potential for the landfill to generate leachate.
No justification is provided in the FS to determine that 5.2 acres is an appropriate size
for a landfill cap.
Allency Response: This again discusses the question of the acreage of the landfill. The
selection ofthe acreage used, 5.2 acres was discussed in a number of sections above"
Since the RI Risk Assessment does not identify any risks posed by the site, there is no
justification for selecting a landfill cap.
Allency Response: The Public Health Evaluation showed unacceptable risks. It was
discussed in 1. and 16. above that the Public Health Evaluation replaces Chapter 6,
the Risk Assessment portion of the RI.
The selection of the proposed remedy did not give sufficient weight to the cost criterion
(one of the nine criteria required to be evaluated under the NCP).
AlZencv Resoonse: Based on the findings of the RI and using the nine criteria required
under the National Contingency Plan for the FS, Alternative 4 is the best alternative.
Cost is a balancing criteria and must be weighed against protectiveness, permanence
and the other criteria. Alternative 4 may be more costly than Alternative 3, but offers
the highest level oCprotection Cor human health and the environment. Alternative 3,
while less costly, ia not protective, nor does it provide permanent relieC Crom exposure
to .... contaminated groundwater and soils. The people will be exposed to inhalation
d1iidac showering and air exposures Crom the windblown dust from the surface of the
181111S1) .
The Public Health Evaluation report is flawed because it is based on data from the RI,
which itselC is deCective due to study design deficiencies; and, because oC conservative
assumptions inherent.to this type oCevaluation.
AlZencv Resoonse: As stated previously, the Public Health Evaluation is part of the
RIIFS and the public record on this NPL Site. The Public Health Evaluation is not
flawed. The EPA guidance was utilized for conducting the Risk Assessment in the
Public Health Evaluation. The statement on "conservative assumptions" as to the
extent oC human exposure and the sources oC uncertainty in any risk assessment are
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standard caveats thai are included in any good risk assessment. The ini'ormaiion
is the best available under present technology. It is standard to consider health risks
conservatively in order to assure the protection of public health.
26. The commenter summarizes his letter by indicating that there is no factual basis for
implementing a remedial action at the Welsh Road/Barkman Landfill Site and that
the site -should be delisted from the NPL.
Agency Response: EPA stands by its position that Alternative 4 is the best choice for
the contamination that exists from the Welsh Road/Barkman Landfill NPL Site.
As stated in the response to comment number 2, the results of
the site investigation, and the conclusions from the Public Health
Evaluation do reach the conclusion that there is a significant
threat to human health posed by the site. These conclusions thus
justify the selection of remedial action for the Walsh Site.
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