National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List: Deletion of the Union Chemical Co., Inc. Superfund Site, 34508-34513 [2018-15622]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 83, Number 140 (Friday, July 20, 2018)]
[Proposed Rules]
[Pages 34508-34513]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-15622]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 300

[EPA-HQ-SFUND-1989-0011; FRL-9981-00--Region 1]


National Oil and Hazardous Substances Pollution Contingency Plan; 
National Priorities List: Deletion of the Union Chemical Co., Inc. 
Superfund Site

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule; notice of intent.

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SUMMARY: The Environmental Protection Agency (EPA) Region 1 is issuing 
a Notice of Intent to Delete the Union Chemical Co., Inc. Superfund 
Site (Site) located in South Hope, Maine, from the National Priorities 
List (NPL) and requests public comments on this proposed action. The 
NPL, promulgated pursuant to section 105 of the Comprehensive 
Environmental Response, Compensation, and Liability Act (CERCLA) of 
1980, as amended, is an appendix of the National Oil and Hazardous 
Substances Pollution Contingency Plan (NCP). The EPA and the State of 
Maine, through the Department of Environmental Protection (MEDEP), have 
determined that all appropriate response actions under CERCLA, other 
than operation and maintenance, monitoring and Five-Year Reviews, have 
been completed. However, this deletion does not preclude future actions 
under Superfund.

DATES: Comments must be received by August 20, 2018.

ADDRESSES: Submit your comments, identified by Docket ID no. EPA-HQ-
SFUND-1989-0011, by one of the following methods:
     https://www.regulations.gov. Follow the on-line 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from Regulations.gov. The EPA may publish any 
comment received to its public docket. Do not submit electronically any 
information you consider to be Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. 
Multimedia submissions (audio, video, etc.) must be accompanied by a 
written comment. The written comment is considered the official comment 
and should include discussion of all points you wish to make. The EPA 
will generally not consider comments or comment contents located 
outside of the primary submission (i.e., on the web, cloud, or other 
file sharing system). For additional submission methods, the full EPA 
public comment policy, information about CBI or multimedia submissions, 
and general guidance on making effective comments, please visit https://www2.epa.gov/dockets/commenting-epa-dockets.
     Email: [email protected] or [email protected].
     Mail:

Terrence Connelly, U.S. EPA, 5 Post Office Square, Suite 100, Mail Code 
OSSR 07-1, Boston, MA 02109-3912
ZaNetta Purnell, U.S. EPA, 5 Post Office Square, Suite 100, Mail Code 
OSSR 01-1, Boston, MA 02109-3912

    Hand delivery: U.S. EPA, 5 Post Office Square, Suite 100, Boston, 
MA. Such deliveries are only accepted during the Docket's normal hours 
of operation, and special arrangements should be made for deliveries of 
boxed information.
    Instructions: Direct your comments to Docket ID no. EPA-HQ-SFUND-
1989-0011. EPA's policy is that all comments received will be included 
in the public docket without change and may be made available online at 
https://www.regulations.gov, including any personal information 
provided, unless the comment includes information claimed to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Do not submit information that you 
consider to be CBI or otherwise protected through https://www.regulations.gov or email. The https://www.regulations.gov website is 
an ``anonymous access'' system, which means EPA will not know your 
identity or contact information unless you provide it in the body of 
your comment. If you send an email comment directly to EPA without 
going through https://www.regulations.gov, your email address will be 
automatically captured and included as part of the comment that is 
placed in the public docket and made available on the internet. If you 
submit an electronic comment, EPA recommends that you include your name 
and other contact information in the body of your comment and with any 
disk or CD-ROM you submit. If EPA cannot read your comment due to 
technical difficulties and cannot contact you for clarification, EPA 
may not be able to consider your comment. Electronic files should avoid 
the use of special characters, any form of encryption, and be free of 
any defects or viruses.
    Docket: All documents in the docket are listed in the https://www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in the hard 
copy. Publicly available docket materials are available either 
electronically in https://www.regulations.gov or in hard copy at:
    U.S. EPA Region 1, Superfund Records Center, 5 Post Office Square, 
Suite 100, Boston, MA 02109, Phone: 617-918-1440, Monday- Friday: 9:00 
a.m.-5:00 p.m., Saturday and Sunday--Closed.

FOR FURTHER INFORMATION CONTACT: Terrence Connelly, Remedial Project 
Manager, U.S. Environmental Protection Agency, Region 1, Mail Code OSSR 
07-1, 5 Post Office Square, Boston, MA 02109-3912, (617) 918-1373, 
email [email protected].

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Introduction
II. NPL Deletion Criteria
III. Deletion Procedures
IV. Basis for Site Deletion

I. Introduction

    EPA Region 1 announces its intent to delete the Union Chemical Co., 
Inc Superfund Site (Site) from the National Priorities List (NPL) and 
requests public comment on this proposed action. The NPL constitutes 
Appendix B of 40 CFR part 300 which is the National Oil and Hazardous 
Substances Pollution Contingency Plan (NCP), which EPA promulgated 
pursuant to section 105 of the Comprehensive Environmental Response, 
Compensation and Liability Act (CERCLA) of 1980, as amended. EPA 
maintains the NPL as the list of sites that appear to present a 
significant risk to public health, welfare, or the environment. Sites 
on the NPL may be the subject of remedial actions financed by the 
Hazardous Substance Superfund (Fund). As described in 40 CFR

[[Page 34509]]

300.425(e)(3) of the NCP, sites deleted from the NPL remain eligible 
for Fund-financed remedial actions if future conditions warrant such 
actions.
    EPA will accept comments on the proposal to delete this site for 
thirty (30) days after publication of this document in the Federal 
Register.
    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 Site and demonstrates how it 
meets the deletion criteria.

II. NPL Deletion Criteria

    The NCP establishes the criteria that EPA uses to delete sites from 
the NPL. In accordance with 40 CFR 300.425(e), sites may be deleted 
from the NPL where no further response is appropriate. In making such a 
determination pursuant to 40 CFR 300.425(e), EPA will 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 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.
    Pursuant to CERCLA section 121(c) and the NCP, EPA conducts Five-
Year Reviews to ensure the continued protectiveness of remedial actions 
where hazardous substances, pollutants, or contaminants remain at a 
site above levels that allow for unlimited use and unrestricted 
exposure. EPA conducts such Five-Year Reviews even if a site is deleted 
from the NPL. EPA may initiate further action to ensure continued 
protectiveness at a deleted site if new information becomes available 
that indicates it is appropriate. 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) EPA consulted with the State before developing this Notice of 
Intent to Delete.
    (2) EPA has provided the State 30 working days for review of this 
notice prior to publication of it today
    (3) In accordance with the criteria discussed above, EPA has 
determined that no further response is appropriate;
    (4) The State of Maine, through its Department of Environmental 
Protection (MEDEP), has concurred with deletion of the Site from the 
NPL.
    (5) Concurrently with the publication of this Notice of Intent to 
Delete in the Federal Register, a notice is being published in a major 
local newspaper, the Bangor Daily News. The newspaper notice announces 
the 30-day public comment period concerning the Notice of Intent to 
Delete the Site from the NPL.
    (6) The EPA placed copies of documents supporting the proposed 
deletion in the deletion docket and made these items available for 
public inspection and copying at the Site information repository 
identified above.
    If comments are received within the 30-day public comment period on 
this document, EPA will evaluate and respond appropriately to the 
comments before making a final decision to delete. If necessary, EPA 
will prepare a Responsiveness Summary to address any significant public 
comments received. After the public comment period, if EPA determines 
it is still appropriate to delete the Site, the Regional Administrator 
will publish a final Notice of Deletion in the Federal Register. Public 
notices, public submissions and copies of the Responsiveness Summary, 
if prepared, will be made available to interested parties and in the 
Site information repository listed above.
    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:

Site Background and History

    The Union Chemical Co., Inc. Superfund Site, CERCLIS ID: 
MED042143883, is located in South Hope, Knox County, Maine, on the 
south side of Route 17 in a rural residential area. The Site is bounded 
by Quiggle Brook, a southerly flowing stream, on the east and 
southeast, by undeveloped forested land to the south and southwest and 
a vacant residential lot to the west.
    Union Chemical Company began operations in 1967, as a paint 
stripping and solvent manufacturing business. Initially, patented 
solvents were manufactured and utilized on the premises, and 
distributed nationally. The Company expanded operations to include the 
recycling of used stripping compounds and solvents from other 
businesses. Operations were further expanded in 1982 to include a full-
scale, fluidized-bed incinerator to treat waste solvents and other 
compounds. Operations ceased in 1985.
    The risk assessment conducted during EPA's Remedial Investigation 
indicated that there would be unacceptable carcinogenic and non-
carcinogenic risks from future ingestion of the groundwater at the Site 
due to concentrations of contaminants.
    On June 24, 1988, EPA proposed the Site for listing on the NPL and 
on October 4, 1989, listing on the NPL was finalized. The Federal 
Register citations for these notices are FR Vol. 53, No. 122, 23978-
23986 and FR Vol. 54, No. 191, 41015-41025, respectively.
    MEDEP closed the hazardous waste treatment operations at the Site 
in June 1984. At that time approximately 2,000-2,500 55-gallon drums 
and 30 liquid storage tanks were present at the Site. These drums, 
their contents, and the contents of the storage tanks were removed by 
EPA and MEDEP by the end of November 1984.
    At present, contamination remains in the groundwater at the Site 
that EPA, with consent from MEDEP, determined in 2013 to be technically 
impracticable to restore. In 2017, a Declaration of Environmental 
Covenant, which among other things, prohibits the use of groundwater, 
was recorded in the chain of title for the properties comprising the 
Site. This deed restriction limits how the Site can be redeveloped.

Remedial Investigation and Feasibility Study (RI/FS)

    The scope of the Remedial Investigation was comprehensive, 
evaluating the nature and extent of contamination in the facility's 
buildings and underlying soils, unsaturated and saturated soils on the 
rest of the property, in groundwater in the overburden soils and in 
bedrock, and in surface water. Additionally, the Remedial Investigation 
collected soil samples from nearby properties to identify potential 
airborne contamination which may have occurred as a result of Union 
Chemical

[[Page 34510]]

Company's past operation of the Site's hazardous waste incinerator.
    The Feasibility Study screened seven on-site soil remedial 
alternatives, six alternatives for groundwater and surface water, five 
alternatives for the facilities, and two alternatives for off-site 
soils. All but one on-site soil alternative was retained for detailed 
analysis. The on-site soil alternatives analyzed in detail included No-
Action; Limited Action; Site Capping; Soil Excavation and Low-
Temperature Thermal Aeration Treatment; In-Situ Soil Aeration; and Soil 
Excavation and High-Temperature Thermal Treatment. The groundwater and 
surface water alternatives analyzed in detail included No-Action; 
Limited Action; Groundwater Extraction with On-Site Treatment and 
Discharge to Quiggle Brook; Vacuum-Enhanced Groundwater Extraction with 
On-Site Treatment and Discharge to Quiggle Brook; Groundwater 
Extraction with On-Site Treatment and Reinjection; and Vacuum-Enhanced 
Groundwater Extraction with On-Site Treatment and Reinjection. The five 
alternatives for the facilities included No-Action; Limited Action; 
Facilities Decontamination only; Facilities Decontamination and 
Demolition; and Facilities Demolition and Disposal without 
Decontamination. The two off-site soil alternatives were No Action and 
Limited Action.

Selected Remedy

    In the 1990 Record of Decision (ROD) EPA selected a remedy that 
specified decontamination and demolition of facilities with off-site 
disposal of debris; soil excavation with on-site low-temperature 
thermal aeration; vacuum-enhanced groundwater extraction, on-site 
treatment, and discharge of treated groundwater to Quiggle Brook with 
institutional controls; and limited action for off-site soils.
    The Remedial Investigation identified eight Remedial Action 
Objectives:
    1. Prevent further leaching and migration into the groundwater of 
contaminants in the soils on the Site, by removal and treatment of 
contaminants above specific concentrations throughout the Site.
    2. Provide rapid restoration of the contaminated groundwater 
throughout the Site, to concentrations that will protect current and 
future users, as well as natural resources (i.e., wildlife) that come 
into contact with the contaminants contained within the groundwater.
    3. Protect off-site groundwater and surface waters (particularly 
Quiggle Brook) by preventing further migration of the contaminated on-
site groundwater.
    4. Prevent ingestion or absorption of contaminants (particularly 
dioxins) contained within the incinerator equipment remaining on the 
Site.
    5. Prevent inhalation of friable asbestos from the Still Building.
    6. Remove all existing structures located on the Site to allow for 
the cleanup of contaminated soils found throughout the Site.
    7. Remove all other contaminated materials from the facilities so 
that the Site will be suitable for all potential future uses.
    8. Further evaluate and, if necessary, minimize and/or mitigate any 
potential risks to public health and the environment from potential 
soil impacts due to contaminants which were previously emitted from the 
Union Chemical Company incinerator.
    In 1992, EPA entered into a Consent Decree with certain Settling 
Defendants to conduct Remedial Design and Remedial Action at the Site 
under EPA oversight.
    The remedy selected in the 1990 ROD was modified in 1994, 1997, and 
2001 by three Explanations of Significant Differences (ESD) and in 2013 
by a ROD Amendment. In June 1994 EPA approved a request from the 
Settling Defendants to change the soil cleanup technology from low-
temperature thermal aeration to soil vapor extraction (SVE) with hot 
air injection. In addition to the change in technology, EPA also set a 
deadline of five years for achieving the soil cleanup standards.
    EPA issued a second ESD for the Site in September 1997 that 
modified the remedy for off-site soils. The 1997 ESD changed the length 
of time specified in the ROD for meteorological data collection from 
five years to three years, thus moving forward the timeframe for 
collection of off-site soil samples to determine whether the operations 
of the Union Chemical Company incinerator resulted in deposition of 
contaminants off-site.
    A third ESD was issued in September 2001 that documented a change 
in the technical approach for treatment of contaminated groundwater and 
changed the location for discharge of treated groundwater. Three 
innovative in situ addition treatment technologies, (i.e., potassium 
and sodium permanganate, concentrated hydrogen peroxide, and molasses 
and sodium lactate) were injected into groundwater in specific portions 
of the Site to treat contaminated groundwater. With fewer extraction 
wells needed to control contaminant migration, discharge of treated 
water changed from surface water discharge to reinjection into the 
ground upgradient of the extraction wells.
    In November 2013, EPA issued a ROD Amendment in which it waived 
groundwater cleanup levels due to technical impracticability. The ROD 
Amendment was necessary because (1) the original groundwater remedy had 
reached the limits of its effectiveness, (2) the three innovative in 
situ technologies had proven unsuccessful in attaining the groundwater 
cleanup standards, and (3) an evaluation of cleanup alternatives 
indicated that no technology was available for achieving groundwater 
cleanup standards in a reasonable timeframe due to Site-specific 
hydrogeological and contaminant conditions. The ROD Amendment also 
adjusted institutional control requirements for the Site.

Response Actions

    In October 1993 EPA approved the Facilities Remedial Design, and 
the decontamination and demolition of facilities and off-site disposal 
of debris was completed in the spring of 1994.
    Beginning in 1994 and continuing into 1996, on-site meteorological 
data was collected to support the off-site soils component of the ROD. 
In October 1996 EPA and the Settling Defendants performed joint off-
site soil investigation and in September 1997 EPA issued an ESD 
documenting no further action was necessary for the off-site soils.
    In April 1995 EPA approved the SVE and groundwater Remedial Design. 
Construction included 28 SVE wells, 94 hot air injection points, 33 
groundwater extraction wells, and the integrated treatment system and 
was completed in December 1995. Both systems began operation in January 
1996. In April 1997 EPA and MEDEP performed a final inspection for both 
systems and declared that the remedy was operational and functional.
    The rate of mass removal of VOCs decreased dramatically between 
1996 and 1999 using the groundwater extraction system, indicating that 
the extraction system was becoming less efficient due to the Site-
specific hydrogeologic and chemical limitations. EPA and MEDEP approved 
the Settling Defendants' request to employ innovative in situ 
technologies to enhance the reduction of contaminant concentrations. 
The first technology involved the injection of permanganate. As a 
strong oxidizer, the permanganate was expected to accelerate the 
destruction of dissolved chlorinated VOCs. A potassium permanganate 
pilot study was completed in October 1997. Based on the results of that 
study,

[[Page 34511]]

potassium and sodium permanganate were used on an expanded basis in the 
summers of 1998, 1999, and 2000 in an attempt to achieve further 
reductions in VOC concentrations.
    The second in situ approach was carried out in June 2000 with the 
injection of 5% hydrogen peroxide solution into injection well P-17. 
This well was selected as it is in the central area of the source area 
where the highest VOC concentrations had been detected. Due to the low 
capacity of P-17 and concerns about the integrity of the mixing tank, 
EPA decided to discharge the remaining solution to several additional 
wells located immediately adjacent to well P-17. Comparison of baseline 
sampling results to four-week post addition results revealed VOC 
concentrations rebounded to their baseline levels, indicating that the 
VOC reductions initially achieved were short-term and not sustained.
    Given the relative short half-lives of permanganate and hydrogen 
peroxide, carbon sources in the form of molasses and sodium lactate 
were added in August and November 2001 to create a reducing environment 
to enhance degradation of chlorinated ethane compounds by reductive 
dechlorination. Lactate addition was carried out again in August 2002.

Cleanup Levels

    After EPA and MEDEP approval in March 1998, the Settling 
Defendants' operation of the SVE system and hot air injection was 
discontinued to allow the soils to return to equilibrium prior to the 
closure-sampling program. Closure sampling was completed in the fall of 
1998. Statistical analysis of the data by three groups working 
independently indicated that the soils had been cleaned up to below the 
ROD-specified cleanup levels.
    Post-ROD groundwater and surface water monitoring began in the 
summer of 1992. The monitoring well network includes wells in the 
source area, in areas with the highest groundwater concentrations, and 
perimeter wells, near the downgradient boundaries of previously 
detectable concentrations. The monitoring leading up to the 2007 Five-
Year Review did not show any concentration increases in the perimeter 
wells, indicating that the plume had not expanded since the extraction 
system was deactivated in 2000. Subsequent monitoring has confirmed 
that the plume has stabilized, yet remains above the ROD-established 
performance standards. Consequently, EPA issued the ROD Amendment in 
2013 that included a Technical Impracticability waiver recognizing 
groundwater performance standards would not be attained in a reasonable 
timeframe because of Site geology, hydrology, and characteristics of 
the contaminants. Long-term groundwater monitoring will continue to be 
performed to ensure that the plume is stable and not migrating out of a 
designated Technical Impracticability Zone, which reaches the Site 
property boundaries except for the upgradient northwest corner of the 
Site.

Operation and Maintenance

    The Operation and Maintenance (O&M) activities associated with the 
Site have been periodically updated as the on-site soil component was 
completed and again when active groundwater restoration ceased. O&M 
activities now consist of annual inspections, long-term monitoring of 
groundwater and surface water every other year, and ongoing 
decommissioning of the treatment building and redundant monitoring 
wells. These activities are outlined in bi-annual work plans that are 
submitted and implemented after EPA and MEDEP review and approval.
    Following acceptance of the soil closure sampling results, unused 
wells and piping were decommissioned in accordance with the O&M Plan.
    The extraction system has been deactivated. The effluent discharge 
line from the treatment building was flushed out, then disconnected 
below the ground surface and grouted. The external piping from the 
groundwater extraction wells was removed, and groups of extraction 
wells were decommissioned in 2005, 2006, and 2010.
    The 1990 ROD and 2013 ROD Amendment required the implementation of 
institutional controls for the Site Property and nearby properties to 
protect human health and the environment. On August 2, 2017, MEDEP 
recorded a Declaration of Environmental Covenant in the chain of title 
for the two lots comprising the Site (collectively, Site Property) at 
the Knox County Registry of Deeds (Volume 5192, Page 306). Pursuant to 
Maine's Uniform Environmental Covenants Act, MEDEP, as the receiver of 
the Site Property pursuant to a 1986 court order, granted the property 
rights under the Declaration of Environmental Covenant to itself, and 
will also serve as the holder of these property interests. EPA has 
third party rights of enforcement under the instrument. Among other 
things, the Declaration of Environmental Covenant: (1) Prohibits the 
extraction of groundwater; (2) prohibits the destruction, obstruction, 
tampering, or disruption of wells; (3) prohibits the discharge or 
injection of liquids to the subsurface; (4) prohibits the accumulation, 
storage, or stockpiling of wastes, as defined in Maine Solid Waste 
Management Rules, Chapter 400, and operation of a junkyard or 
automotive scrapyard, as defined in 30 M.R.S. Sec.  3752; (5) requires 
a sub-slab vapor barrier and ventilation system or a sub-slab 
depressurization system for any constructed buildings, and (6) provides 
for EPA and MEDEP access to the Site Property.
    In addition to institutional controls for the Site Property, the 
1990 ROD also identified a number of institutional controls that could 
be taken for properties beyond the Site Property. These controls 
included a restriction on the use of groundwater from existing bedrock 
wells that are hydraulically connected to the Site, specifically the 
well on Town of Hope's Tax Map 8 Lot 45, and advisory controls (e.g., 
well advisories) on surrounding properties.
    The Settling Defendants entered into a Lease and Indenture 
Agreement with the owners of Map 8 Lot 45 on May 18, 1992 and the State 
of Maine, acting by and through MEDEP. This agreement prohibited the 
use of the bedrock well in perpetuity unless released by the Settling 
Defendants and MEDEP.
    The 2013 ROD Amendment also calls for environmental deed 
restrictions or other mechanisms to limit the use of properties 
adjacent to the Site, as deemed necessary by EPA based on new 
information including but not limited to the development (or 
installation of drinking water wells) on properties adjacent to the 
Site or movement of the leading edge of either plume. To date, EPA has 
not determined that it is necessary to implement other land use 
restrictions on the properties adjacent to the Site.
    With the recording of the Declaration of Environmental Covenant, 
the criteria for EPA's Sitewide Ready for Anticipated Use Government 
Performance and Results Act Measure were complete, and EPA Region 1 
signed the Superfund Property Reuse Evaluation Checklist for Reporting 
on August 17, 2017.

Five-Year Review

    EPA conducts Five-Year Reviews of the Site because hazardous 
substances, pollutants, or contaminants remain on-site above levels 
that allow for unlimited use and unrestricted exposure. These reviews 
are statutory and four have been completed with the most recent one 
completed in September 2017.
    The 2017 Five-Year Review concluded the remedy currently

[[Page 34512]]

protects human health and the environment because MEDEP is the court-
appointed receiver of the Site Property and as such, use of the Site 
Property is controlled by MEDEP, there is no evidence of current 
exposure, institutional controls are in place, access to the Site is 
assured, and long-term monitoring continues. The 2017 Five-Year Review 
identified one issue, the potential presence of the chemicals 
perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and 
1,4-dioxane, and recommended they be included in an upcoming monitoring 
event to determine if these compounds are associated with the Site.
    Pursuant to that Five-Year Review recommendation, on October 23, 
2017, the Settling Defendants collected groundwater and surface water 
samples for PFOA and PFOS from two overburden wells, two bedrock wells, 
and two surface water locations. The samples were analyzed via EPA 
Method 537, Version 1.1. Modified, and QA/QC review determined that 
results were of acceptable quality. Three of the four wells had 
concentrations below EPA's drinking water advisory level of 70 ng/L 
(nanograms per liter or parts per trillion) for both PFOA and PFOS.
    The overburden well with the exceedance of both PFOA and PFOS is 
historically the most contaminated well in the ongoing long-term Site 
monitoring and is located immediately downgradient of the former 
facility's discharge trench. The other overburden well and the two 
bedrock wells are located 150-450 feet farther downgradient from the 
well with the exceedance (and for the bedrock wells, the property 
boundary is another 200 feet or more downgradient beyond them). All the 
wells are within the Technical Impracticability Zone created under the 
2013 ROD Amendment.
    In the two surface water samples collected from Quiggle Brook, PFOS 
and PFOA were not individually detected at concentrations exceeding the 
method detection limit of 1.0 ng/L but had estimated PFOA 
concentrations at the instrument detection limit of 1.0 ng/L at the 
location upstream of the Site and 0.8 ng/L at the long-term surface 
water monitoring location. There is no EPA advisory level for surface 
water. Maine Center for Disease Control has established a surface water 
advisory level of 170 ng/L based on recreational exposure (swimming and 
wading) and these sample results are below that surface water advisory 
level.
    In 2010, 1,4-dioxane was added to the monitoring program. Due to 
the elevated levels of other compounds in eight of the ten wells in the 
monitoring program, the samples were diluted for analysis and 
correspondingly, the Reported Detection Limits (RDL) were raised. 
Consequently, the 1,4-dioxane levels were reported as below the 
specific reporting limit, ranging from <20 ppb to <2,000 ppb. However, 
in the four monitoring events, 2010, 2012, 2014, and 2016, as the RDL 
has dropped in five of the eight wells, 1,4-dioxane remained below the 
reporting limit. Of the two wells where 1,4-dio+xane has been detected, 
the concentrations have decreased so that the latest results are now 
also below their respective reporting limits of <20 and <100 ppb. There 
is no Maximum Contaminant Level standard for 1,4-dioxane nor was 1,4-
dioxane included the 1992 Maine Maximum Exposure Guidelines (ME MEGs), 
which is the Applicable or Relevant and Appropriate Requirement. The 
current, but unpromulgated ME MEG for 1,4-dioxane is 4 ppb.
    With the recent PFAS sampling indicating one exceedance in four 
monitoring wells in the Technical Impracticability Zone, PFAS will be 
added to the long-term monitoring program coincident with every 
monitoring event that precedes a Five-Year Review.

Community Involvement

    There was an established community group, Hope Committee for a 
Clean Environment (HCCE) that was active during the RI/FS and received 
support through an EPA technical assistance grant. From 1992 through 
the early 2000s, while Remedial Design and then active remediation of 
the on-site soils and groundwater, and investigation of the off-site 
soils were underway, HCCE met regularly with EPA, MEDEP, and the 
Settling Defendants' Project Coordinator. With the termination of the 
in situ technologies, these meetings ceased. Communication between 
HCCE, EPA, and MEDEP is now primarily through email. In 2005-2006, EPA 
convened meetings with community members to develop re-use options.
    EPA and MEDEP have met frequently with the Hope Town Administrator 
and have periodically updated the Board of Selectmen. In June 2015, EPA 
and MEDEP attended the Town of Hope's Annual Meeting. At that meeting, 
the Town voted not to assume ownership of the Site Property should 
MEDEP's receivership of the Site Property end. The Town reaffirmed this 
position in an October 10, 2017 letter to MEDEP. Beyond these meetings 
and periodic communication with HCCE and owners of a right-of-way 
easement across the Site Property, there has been little participation 
or involvement from other members of the local community.
    EPA discussed the deletion process with the Town Administrator and 
offered to meet with the Board of Selectmen if the Town desired a 
presentation. Additionally, EPA contacted the HCCE to inform the group 
of EPA's plan to delete the Site.

Determination That the Site Meets the Criteria for Deletion in the NCP

    Remedial Design and Remedial Action (RD/RA) activities at the Site 
were consistent with the ROD, as modified by the ESDs and the ROD 
Amendment, and consistent with EPA RD/RA Statements of Work provided to 
the Settling Defendants. RA plans for all phases of construction 
included a Quality Assurance Project Plan (QAPP) dated February 17, 
1995 and QAPP Revision 1, dated September 22, 2001. The QAPP 
incorporated all EPA and Maine quality assurance and quality control 
procedures and protocols (where necessary). All procedures and 
protocols were followed for soil, groundwater, and surface water 
sampling during the RA. EPA analytical methods were used for all 
validation and monitoring samples during all RA activities. EPA has 
determined that the analytical results are accurate to the degree 
needed to assure satisfactory execution of the RA, and are consistent 
with the ROD and the RD/RA plans and specifications.
    All institutional controls are in place and currently EPA expects 
that no further Superfund response is needed to protect human health 
and the environment, except future Five-Year Reviews and ongoing long-
term monitoring. O&M activities were agreed upon by EPA and the 
Settling Defendants and are documented in the October 2006 O&M Manual. 
These activities include continuing decommissioning of redundant wells, 
securing the functioning wells, and maintenance of the soil cap.
    This Site meets all the site completion requirements as specified 
in OSWER Directive 9320.2-09-A-P, Close Out Procedures for National 
Priorities List Sites. All cleanup actions specified in the ROD, as 
modified by the ESDs and ROD Amendment have been implemented and the 
implemented remedy has achieved the degree of cleanup or protection 
specified in the ROD, as modified by the ESDs and ROD Amendment, for 
all pathways of exposure.
    Confirmatory groundwater monitoring and institutional controls 
provide further assurance that the Site no longer poses any threats to 
human health or the

[[Page 34513]]

environment. The only remaining activity to be performed are Five-Year 
Reviews, monitoring, and O&M activities described above. A bibliography 
of all reports relevant to the completion of this Site under the 
Superfund program is in the administrative record for this deletion.

List of Subjects in 40 CFR Part 300

    Environmental protection, Chemicals, Hazardous waste, Hazardous 
substances, Intergovernmental relations, Penalties, Reporting and 
recordkeeping requirements, Superfund, Water pollution control, Water 
supply.

    Authority: 33 U.S.C. 1321(d); 42 U.S.C. 9601-9657; E.O. 13626, 
77 FR 56749, 3 CFR, 2013 Comp., p. 306; E.O. 12777, 56 FR 54757, 3 
CFR, 1991 Comp., p. 351; E.O. 12580, 52 FR 2923, 3 CFR, 1987 Comp., 
p. 193.

    Dated: July 9, 2018.
Alexandra Dunn,
Regional Administrator, Region 1.
[FR Doc. 2018-15622 Filed 7-19-18; 8:45 am]
BILLING CODE 6560-50-P