[Federal Register Volume 66, Number 146 (Monday, July 30, 2001)]
[Rules and Regulations]
[Pages 39280-39284]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 01-18816]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 300
[FRL-7019-8]
National Oil and Hazardous Substances Pollution Contingency Plan;
National Priorities List
AGENCY: Environmental Protection Agency.
ACTION: Direct final notice of deletion of the Sussex County Landfill
No. 5 Superfund Site from the National Priorities List.
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SUMMARY: The Environmental Protection Agency (EPA) Region III is
publishing a direct final notice of deletion of the Sussex County
Landfill No. 5, Superfund Site (Site), located in Laurel, Delaware from
the National Priorities List (NPL).
The NPL, promulgated pursuant to Section 105 of the Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA) of
1980, as amended, is Appendix B of 40 CFR Part 300, which is the
National Oil and Hazardous Substances Pollution Contingency Plan (NCP).
This direct final notice of deletion is being published by EPA with the
concurrence of the State of Delaware, through the Department of Natural
Resources and Environmental Control, because EPA has determined that
all appropriate response actions under CERCLA have been completed and,
therefore, further remedial action pursuant to CERCLA is not
appropriate.
DATES: This direct final deletion will be effective September 28, 2001
unless EPA receives adverse comments by August 29, 2001. If adverse
comments are received, EPA will publish a timely withdrawal of the
direct final deletion in the Federal Register informing the public that
the deletion will not take effect.
[[Page 39281]]
ADDRESSES: Comments may be mailed to: Richard Kuhn, Community
Involvement Coordinator (3HS43), E-mail: kuhn.richard@epa.gov, U.S. EPA
Region III, 1650 Arch Street, Philadelphia, PA 19103-2029, (215) 814-
3063 or 1-800-352-1973, ext. 4-3063.
Information Repositories: Comprehensive information about the Site
is available for viewing and copying at the Site information
repositories located at: U.S. EPA Region III, Regional Center for
Environmental Information (RCEI), 1650 Arch Street (2nd Floor),
Philadelphia, PA 19103-2029, (215) 814-5254, Monday through Friday 8
a.m. to 5 p.m.; Laurel Public Library, 6 East Fourth Street, Laurel, DE
19956, (302) 875-3184, Monday through Thursday 10 a.m. to 8 p.m.,
Friday 10 a.m. to 5 p.m., Saturday 10 a.m. to 2 p.m.; and the Delaware
Department of Natural Resources and Environmental Control, Division of
Air and Waste Management, 391 Lukens Drive, Riveredge Industrial Park,
New Castle, DE 19720, (302) 395-2600, Monday through Friday 8:00 a.m.
to 4:00 p.m.
FOR FURTHER INFORMATION CONTACT: Humberto J. Monsalvo, Jr., Remedial
Project Manager (RPM) (3HS23), E-mail: monsalvo.humberto@epa.gov, U.S.
EPA Region III, 1650 Arch Street, Philadelphia, PA 19103-2029, (215)
814-2163 or 1-800-352-1973 ext. 4-2163, FAX (215) 814-3002.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Introduction
II. NPL Deletion Criteria
III. Deletion Procedures
IV. Basis for Site Deletion
V. Deletion Action
I. Introduction
EPA Region III is publishing this direct final notice of deletion
of the Sussex County Landfill No. 5 Superfund Site from the NPL.
The EPA identifies sites that appear to present a significant risk
to public health or the environment and maintains the NPL as the list
of those sites. As described in 40 CFR 300.425(e)(3) of the NCP, sites
deleted from the NPL remain eligible for remedial actions if conditions
at a deleted site warrant such action.
EPA considers this action to be noncontroversial and routine; as
such, EPA is taking it without prior publication of a notice of intent
to delete. This action will be effective September 28, 2001 unless EPA
receives adverse comments by August 29, 2001 on this notice. If adverse
comments are received within the 30-day public comment period on this
action to delete, EPA will publish a timely withdrawal of this direct
final notice of deletion before the effective date of the deletion and
the deletion will not take effect. EPA will, as appropriate, prepare a
response to comments and continue with the deletion process on the
basis of the notice of intent to delete and the comments already
received. There will not be any additional opportunity to comment.
Section II of this document explains the criteria for deleting
sites from the NPL. Section III discusses procedures that EPA is using
for this action. Section IV discusses the Sussex County Landfill No. 5
Superfund Site and demonstrates how it meets the deletion criteria.
Section V discusses EPA's action to delete the Site from the NPL unless
adverse comments are received during the public comment period.
II. NPL Deletion Criteria
Section 300.425(e) of the NCP provides that releases may be deleted
from the NPL where no further response is appropriate. In making a
determination to delete a release from the NPL, EPA shall consider, in
consultation with the State, whether any of the following criteria have
been met:
i. Responsible parties or other persons have implemented all
appropriate response actions required;
ii. All appropriate Fund-financed (Hazardous Substance Superfund
Response Trust Fund) response under CERCLA has been implemented, and no
further response action by responsible parties is appropriate; or
iii. The remedial investigation has shown that the release poses no
significant threat to public health or the environment and, therefore,
the taking of remedial measures is not appropriate.
Even if a site is deleted from the NPL, where hazardous substances,
pollutants, or contaminants remain at the deleted site above levels
that allow for unlimited use and unrestricted exposure, CERCLA Section
121(c), 42 U.S.C. 9621(c) requires that a subsequent review of the site
be conducted at least every five years after the initiation of the
remedial action at the deleted site to ensure that the action remains
protective of public health and the environment. If new information
becomes available which indicates a need for further action, EPA may
initiate remedial actions. Whenever there is a significant release from
a site deleted from the NPL, the deleted site may be restored to the
NPL without application of the hazard ranking system.
III. Deletion Procedures
The following procedures apply to deletion of the Site:
(1) The EPA consulted with Delaware on the deletion of the Site
from the NPL prior to developing this direct final notice of deletion.
(2) Delaware concurred with deletion of the Site from the NPL
(3) Concurrently with the publication of this direct final notice
of deletion, a notice of the availability of the parallel notice of
intent to delete published today in the ``Proposed Rules'' section of
the Federal Register is being published in a major local newspaper of
general circulation at or near the Site and is being distributed to
appropriate federal, state, and local government officials and other
interested parties; the newspaper notice announces the 30-day public
comment period concerning the notice of intent to delete the Site from
the NPL.
(4) The EPA placed copies of documents supporting the deletion in
the Site information repositories identified above.
(5) If adverse comments are received within the 30-day public
comment period on this notice or the companion notice of intent to
delete also published in today's Federal Register, EPA will publish a
timely notice of withdrawal of this direct final notice of deletion
before its effective date and will prepare a response to comments and
continue with the deletion process on the basis of the notice of intent
to delete and the comments already received.
Deletion of a site from the NPL does not itself create, alter, or
revoke any individual's rights or obligations. Deletion of a site from
the NPL does not in any way alter EPA's right to take enforcement
actions, as appropriate. The NPL is designed primarily for
informational purposes and to assist EPA management. Section
300.425(e)(3) of the NCP states that the deletion of a site from the
NPL does not preclude eligibility for future response actions, should
future conditions warrant such actions.
IV. Basis for Site Deletion
The following information provides EPA's rationale for deleting the
Site from the NPL:
A. Site Location
The Site, also known as the Laurel Landfill, is a 38-acre landfill
located off Route 494 and approximately 1 mile west of the Laurel
Airport in Laurel, Delaware. The surrounding area is agricultural and
residential.
[[Page 39282]]
B. Site History
The landfill was in operation between May 1970 and August 1979 and
during that time accepted municipal and industrial waste. Waste was
disposed in trenches which were excavated into the native soil. Waste
placed in the landfill was covered by approximately two feet of soil
obtained from soil stockpiles generated during the excavation of the
trenches. After the landfill closed in 1979, a transfer station for
municipal waste was operated on the northwest corner of the property
under permit from the Delaware Department of Natural Resources and
Environmental Control (DNREC) until 1993. During the 1980s, several
investigations of the landfill were conducted by DNREC and Sussex
County. As a result of these investigations, DNREC determined that
ground water in the vicinity of the landfill had been impacted by
contaminants coming from the landfill. On August 8, 1988, DNREC and
Sussex County signed a Memorandum of Understanding to support the
development and implementation of the Ground Water Management Zones
(GMZs). GMZs were subsequently developed for the landfill and approved
by DNREC. Three GMZs were established in the area surrounding the
landfill; one of these restricted the installation of new ground water
pumping wells (No Well Zone) and two of these restricted pumping rates
of any new and existing wells (GMZ A-Wells less than 10 g.p.m. and GMZ
B-Wells less than 100 g.p.m.).
In 1986, EPA completed a Site Inspection which indicated that
ground water in the area of the landfill had become contaminated with
volatile organic compounds (VOCs) and metals coming from the landfill.
The Site was proposed for the National Priorities List (NPL) in June
1988 and was added to the list on October 4, 1989. On April 4, 1991 EPA
and Sussex County entered into an Administrative Order on Consent which
required Sussex County to conduct a Remedial Investigation (RI) and
Feasibility Study (FS) for the Site.
Remedial Investigation and Feasibility Study (RI/FS)
Ground water samples obtained from onsite and offsite monitoring
wells and two irrigation wells during the RI indicated ground water was
mainly contaminated with low levels [in the low micrograms per liter
(ug/L) range] of VOCs. Benzene and vinyl chloride were the only VOCs
which were detected at concentrations above the Safe Drinking Water
Act's Maximum Contaminant Levels (MCLs). VOC ground water contamination
extended 1,000 feet down gradient of the northwest corner of the
landfill.
The analytical data generated from the RI showed no apparent
adverse impacts on sediment, soil, and surface water quality at the
landfill.
During the RI, one offsite residential well was found to be
contaminated with vinyl chloride just above the Safe Drinking Water Act
MCL. As a result, Sussex County provided this resident with bottled
water and later in February 1993 Sussex County installed a carbon
filter water treatment system on this well to remove VOCs and an
ultraviolet light to reduce bacteria levels.
In October 1993, Sussex County completed the RI which included EPA-
prepared Baseline Human Health Risk Assessment and Ecological Risk
Assessment. The Risk Assessment indicated that very low levels of
contaminants of concern existed in the ground water which translated
into correspondingly low risk levels at the Site. Based on the results
of the RI and the Risk Assessments, EPA determined that a feasibility
study was not necessary to evaluate remedial alternatives.
Record of Decision Findings
Based on the results of the RI and Risk Assessment and in light of
the activities being taken by DNREC and Sussex County under a Notice of
Conciliation (NOC) signed by both parties in August 1994, EPA did not
require any clean-up action to be taken at the Site under CERCLA. On
December 29, 1994, EPA issued a No Action Record of Decision (ROD)
which stated Five-Year Reviews would be conducted in order to determine
if conditions at the Site remain protective of human health and the
environment.
According to the NOC, Sussex County was to perform the following
activities:
Provide Public Water Supply to Residents Down Gradient of
the Landfill
Establish a Ground Water Monitoring Program
Maintenance of the Vegetated Soil Cover
Restrict Well Installation and/or Operation in the GMZs
Institutional Controls
Characterization of Risk
The baseline risk assessment performed by EPA in 1994 determined
through screening and evaluation of the Site media data that the only
route of exposure of toxicological significance was through ground
water. EPA assessed carcinogenic and non-carcinogenic risks from
current and potential future exposure to contaminated ground water in
residential well RW-02. In addition, EPA assessed carcinogenic and non-
carcinogenic risks due to potential migration of the organic
contaminant plume offsite. EPA used data from monitoring wells LD-1,
LS-7R, and LS-16 to represent the center of the organic contaminant
plume that was considered to be the source of exposure to receptors if
the contaminant plume were to migrate to some offsite point where this
water may be used for future residential purposes.
The risk assessment concluded that very low levels of contaminants
of concern existed in the ground water corresponding to low risk levels
at the Site. The increased carcinogenic risk for the residential
exposure pathway was just slightly above the generally acceptable risk
level of 1.0 E-04. The noncarcinogenic risk, or Hazard Index,
calculated for the residential exposure pathway was 1.23 and the hazard
was mainly attributable to inhalation of volatile organic compounds
during showering. This Hazard Index value was marginally above EPA's
generally acceptable level of 1.0. For the exposure pathway calculated
using monitoring well data, the Hazard Index was 2.68 indicating that
noncarcinogenic effects may be expected to occur if exposure to this
ground water were to occur in the future.
In 1999, EPA conducted a five-year review for the Site. During the
preparation of the Five-Year Review Report, EPA reviewed the ground
water data collected since the ROD date to determine if the risks
associated with the Site had increased, or if assumptions or input
values used in the baseline risk assessments had changed significantly
enough to require a new risk assessment for the Site. The review of the
ground water sampling data for the contaminants of concern revealed
that overall the concentration levels had not increased since the
baseline risk assessment was performed. The assumptions and input
values for the Site contaminants of concern used in the baseline risk
assessment had not changed since the issuance of the ROD with the
exception of the oral exposure reference dose (RfD) for 1,4-
dichlorobenzene, a volatile organic compound. The oral RfD had been
revised to a more stringent value than the RfD used in the baseline
risk assessment. EPA conducted a qualitative assessment and determined
that the Hazard Index calculated for the Site would not significantly
change due to the revised RfD for 1,4-dichlorobenzene. EPA also
conducted an Ecological Risk Assessment to
[[Page 39283]]
evaluate any actual or potential ecological risk as a result of
exposure to Site-related contaminants of concern. This assessment
concluded that a negligible potential exists for negative impact to
habitats onsite and in the surrounding area. The human health and
ecological risk posed by the Site is negligible.
Response Actions
On December 29, 1994 EPA issued a No Action Record of Decision;
therefore, no CERCLA remedial action was conducted at the site.
However, Sussex County performed the following work in accordance with
the requirements of the Notice of Conciliation entered into with DNREC:
(1) Provide Public Water Supply to Residents Down Gradient of the
Landfill. A public water supply well, approximately 300 feet deep, was
installed by Sussex County west of the landfill. The construction of
the public water supply pipeline was completed in 1995 and residential
connections to the system also began. As of December 1995, nineteen
residences were connected to the public water supply system and by
March 1996, one additional connection was completed. Sussex County had
provided a carbon treatment unit for one residential well (RW-02) in
which vinyl chloride had been detected at concentrations above the MCL.
The treatment system was removed and this residential well was renamed
monitoring well LS-20 after the residence was connected to the public
water supply system. The public water supply system is currently owned
and operated by Tidewater Utilities Company. The public supply well is
tested by Sussex County approximately once annually. The Delaware
Department of Public Health currently oversees the Tidewater Utilities
Company monitoring program for the public supply well.
(2) Establish a Ground Water Monitoring Program. A ground water
monitoring program was established by Sussex County and approved by EPA
and DNREC which included quarterly sampling for one year (November
1994-October 1995) and then semi-annual sampling thereafter. The
monitoring program currently consists of monitoring wells within, down
gradient and west of the landfill; residential wells down gradient of
the landfill which have not connected to the public water supply; an
irrigation well; an up gradient residential well and an up gradient
monitoring well. As of 2000, the wells are sampled annually.
The samples are analyzed for volatile organic compounds and ammonia
as nitrogen (N), chloride, soluble iron, soluble manganese, nitrate-
nitrite measured as nitrogen (mg-N/L), total dissolved solids, pH, and
specific conductance.
(3) Maintenance of the Vegetated Soil Cover. The NOC required
Sussex County to maintain the integrity and effectiveness of the
vegetated soil cover to correct any effects of settling, subsidence,
and erosion and to prevent precipitation from eroding or otherwise
damaging the cover which prevents direct contact with the waste
material. In July 1995, DNREC approved the Site Care Work Plan
submitted by Sussex County. The work consisted of clearing and grubbing
areas to be backfilled, backfilling and compacting areas to grade in
order to alleviate standing water and to produce an even fill surface
throughout areas of the landfill designated by DNREC; constructing four
swales in order to encourage drainage of water from the landfill
surface; and grading and seeding the backfilled areas. Sussex County
did not disturb any existing vegetation or trees in the areas of the
landfill that DNREC did not require backfilling and grading. By March
1998, Sussex County had completed all Site care work had been completed
by Sussex County. Sussex County inspects the landfill cover at least
once a year to determine if wastes are exposed, or excessive erosion or
surface water ponding is occurring.
(4) Restrict Well Installation and/or Operation in the GMZs. The
NOC required Sussex County to continue implementing the GMZs as
described in the August 1988 Memorandum of Understanding between the
DNREC and Sussex County. Installation of drinking water wells are
carefully controlled or restricted in the GMZs. There are three areas
within the GMZ:
No well installation area
GMZ-A: limited to wells with a pumping rate of less than
10 gallons per minute (g.p.m.)
GMZ-B: limited to wells with a pumping rate of less than
100 g.p.m.
To date, the GMZs have been maintained and controlled through the
oversight efforts of DNREC and Sussex County.
(5) Institutional Controls. The NOC required Sussex County to
record with the recorder of deeds a notation that will in perpetuity
notify any potential purchaser that the property was used as a solid
waste disposal Site and that land use restrictions under DNREC
Regulations Governing Solid Waste apply. On March 26, 1996, Sussex
County Council recorded a ``Declaration of Restriction'' with the
Sussex County Recorder of Deeds addressing the requirements of the NOC.
In addition, a statement restricting the landfill property from
commercial or residential use and restricting any person from
inhabiting or occupying the land at any future time was included in
this ``Declaration of Restriction.''
Cleanup Standards
EPA issued a No Action Record of Decision in 1994; therefore, no
cleanup standards were established because the low contaminant and
human health and environmental risk levels associated with the Site did
not warrant cleanup activities. Sussex County and DNREC operating under
the requirements of the Notice of Conciliation which both parties
signed in 1994 continue to maintain the Ground Water Management Zones
and the soil surface landfill cover; restrict commercial or residential
use of the landfill, and monitor ground water in and surrounding the
landfill to reduce the potential for exposure of human and
environmental receptors to landfill wastes.
Five-Year Review
In 1999, EPA conducted the first CERCLA Five-Year Review of the
Site to determine if the chosen No Action remedy was still protective
of human health and the environment. In order to evaluate the
protectiveness of the remedy, EPA performed a Site visit, reviewed
data, conducted interviews, and evaluated the work performed at the
landfill since the Record of Decision was signed in 1994. Ground water
data from the Site reviewed during this Five-Year review period
indicated that there are no human exposures to VOCs in ground water at
or surrounding the landfill. The data revealed that the nitrate-nitrite
level in the ground water is elevated above the Safe Drinking Water
Act's Maximum Contaminant Level (MCL). The presence of nitrate or
nitrite in drinking water sources is mainly a concern for infants under
six months due to the possibility of ``Blue Baby Syndrome'' in which an
infant experiences shortness of breath and therefore may look blue.
Elevated levels of nitrate-nitrite above the 10 ug/L MCL were detected
in ground water samples from monitoring and private wells, both up
gradient and down gradient of the landfill indicating that the source
of this nitrate-nitrite is not likely the landfill. EPA discussed the
elevated nitrate-nitrite levels with DNREC and the Delaware Department
of Public Health and learned that it is typical to find nitrate-nitrite
levels in the 10-15 ug/L range in ambient ground water in Sussex
County, Delaware. Since the
[[Page 39284]]
nitrate-nitrite levels in ground water drinking wells in the area of
the landfill are within the ambient (10-15 ug/L) range typically found
in Sussex County and the nitrate-nitrite levels were elevated in
monitoring wells located up gradient of the landfill, the landfill did
not appear to be the source of nitrate-nitrite in ground water. Private
residential wells serving less than 25 people are not regulated by the
Safe Drinking Water Act; therefore, EPA, DNREC and Sussex County
decided to send public information fact sheets to the residents to
inform them of the potential adverse health effects due to elevated
levels of nitrate-nitrite in drinking water and precautions the public
can take to reduce exposure to nitrate-nitrite. In summary, EPA
concluded that conditions at the Site had not worsened and no
additional risks are presented to human health and the environment at
the Site since the signing of the No Action ROD in 1994; therefore, EPA
concluded that the No Action remedy was still protective of human
health and the environment.
In the 1999 Five-Year Review Report, EPA recommended the following
activities be performed by Sussex County so that it can continue to
monitor the conditions at the landfill and surrounding area in order to
ensure continued protectiveness of human health and the environment.
These recommended actions are the following: continue the ground water
monitoring program, modifying it as necessary, and maintain the Ground
Water Management Zones; continue maintenance of the vegetative soil
landfill cover; and notify the residents nearby the landfill who have
not been connected to the public water supply system of the elevated
levels of nitrate-nitrite in the ground water and that the source of
this nitrate-nitrite does not appear to be the landfill.
Sussex County in cooperation with DNREC followed up on these
recommendations by issuing public information Fact Sheets to the nearby
residents who still use ground water from private wells. The facts
sheets informed the residents of the presence of elevated levels of
nitrates-nitrites in the water and discussed precautions they could
follow to reduce the impact of these nitrate-nitrites on their health.
In addition, Sussex County is, with oversight by DNREC, continuing to
maintain the integrity and effectiveness of the landfill vegetative
soil cover as required in the NOC, and maintain the Ground Water
Management Zones. In addition, Sussex County has modified the Ground
Water Monitoring Program in accordance with the NOC and MOU and
continues to conduct the Ground Water Monitoring Program at the Site
according to DNREC's requirements and as outlined in a revised
Memorandum of Understanding (MOU-2) signed between DNREC and Sussex
County on March 14, 2000.
Since waste is being left in place at the landfill, EPA will
continue to conduct Five-Year Reviews at the Site. The date for the
next EPA five-year review is December 2004.
Community Involvement
Public participation activities have been satisfied as required in
CERCLA Section 113(k), 42 U.S.C. 9613(k), and CERCLA Section 117, 42
U.S.C. 9617. Documents in the deletion docket which EPA relied on for
recommendation of the deletion from the NPL are available to the public
in the information repositories.
V. Deletion Action
The EPA, with concurrence of the State of Delaware, has determined
that all appropriate responses under CERCLA have been completed, and
that no further response actions, under CERCLA, other than Five-Year
Reviews, are necessary. Therefore, EPA is deleting the Site from the
NPL.
EPA considers this action to be noncontroversial and routine; as
such, EPA is taking it without prior publication of a notice of intent
to delete. This action will be effective September 28, 2001 unless EPA
receives adverse comments by August 29, 2001 on a parallel notice of
intent to delete published in the Proposed Rule section of today's
Federal Register. If adverse comments are received within the 30-day
public comment period on the proposal, EPA will publish a timely
withdrawal of this direct final notice of deletion before the effective
date of the deletion, and it will not take effect, EPA will then
prepare a response to comments and continue with the deletion process
on the basis of the notice of intent to delete and the comments already
received. There will not be any additional opportunity to comment.
List of Subjects in 40 CFR Part 300
Environmental protection, Air pollution control, Chemicals,
Hazardous waste, Hazardous substances, Intergovernmental relations,
Penalties, Reporting and recordkeeping requirements, Water pollution
control, Water supply.
Dated: July 23, 2001.
Thomas C. Voltaggio,
Acting Regional Administrator, EPA Region III.
For the reasons set out in this document, 40 CFR part 300 is
amended as follows:
PART 300--[AMENDED]
1. The authority citation for Part 300 continues to read as
follows:
Authority: 33 U.S.C. 1321(c)(2); 42 U.S.C. 9601-9657; E.O.
12777, 56 FR 54757, 3 CFR, 1991 Comp., p.351; E.O. 12580, 52 FR
2923, 3 CFR, 1987 Comp., p.193.
Appendix B--[Amended]
2. Table 1 of Appendix B to Part 300 is amended under Delaware
(``DE'') by removing the site name, Sussex County Landfill No. 5,
and the city, Laurel, DE.
[FR Doc. 01-18816 Filed 7-27-01; 8:45 am]
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