Technology
                  News & Trends
                                 EPA 542-N-14-001 | Issue No. 65, May 2014
This issue of Technology News & Trends highlights how remedies for contaminated sites may be vulnerable
to the impacts of climate change and how measures may be taken to adapt remedies to the impacts. Potential
impacts include extreme or sustained changes in temperatures, increased flood events or droughts, increased
wind intensity, more frequent and intense wildfires, and sea level rise. The U.S. Environmental Agency (EPA)
Superfund program has developed an approach that raises awareness of the vulnerabilities and applies climate
change science as a standard business practice in site cleanup projects. Articles featured in this issue examine
vulnerabilities at three National Priorities List sites, describe the effects of intense weather events at these sites,
and detail adaptation measures already implemented or planned to increase the remedies' resilience to climate
change impacts.

Site Operations and Remedy Design: Hurricane  Irene Flooding and Adaptation at the American
Cyanamid Site

Contributed by Joe Battipaqlia, U.S. Environmental Protection
Agency, Region 2

Hurricane Irene struck the coast of New Jersey in late  August
2011. On August 27, associated floodwaters overtopped a 100-
year flood control berm that surrounds much of the American
Cyanamid site, a 435-acre National Priorities List site located
along the Raritan River in central  New Jersey's Somerset County.
Approximately 214 million gallons of standing water remained in
the site's  north area as floodwaters receded (Figure 1). Due to the
potential for major storm events to occur in the future,  extensive
flood plans were developed approximately six months  later to
integrate  preparedness procedures, evacuation plans  and post-
flood response requirements into site operations. A number of
adaptation measures were implemented throughout the site to
increase its flooding resilience and improve flood response
efforts. Flood mitigation measures were also integrated into the
preliminary design of a remedy selected  in 2012, which
addresses six impoundments, site-wide soil and groundwater.
Figure 1. Raritan River from its typical
elevation of approximately 18 feet above mean
sea level to an elevation of 42 feet during
Hurricane Irene, which inundated the north
area of the American Cyanamid site with five
feet of standing water after floodwaters
receded.
The site contains 27 impoundments, 21 of which were used to dispose of chemical sludge and other wastes.
Onsite soil and groundwater are contaminated with volatile organic compounds (VOCs), semi-VOCs and
metals; the main contaminants of concern are benzene, 1,2-dichlorobenzene, n-nitrosodiphenylamine,
nitrobenzene and naphthalene. The two most contaminated
impoundments (1 and 2) each contain waste 13 to 16 feet deep and
cover approximately two acres. To maintain hydraulic control of
groundwater in the north area, a minimum of 650,000 gallons of
groundwater per day has been extracted and discharged to a nearby
sewage treatment plant since 1988.

Floodwaters entering the site were prevented from exiting due to an
inoperative mechanical sluice gate, which created a "bathtub" within
the 10- to 12-foot flood control berm of the 268-acre north area. After
analyzing samples of the standing floodwater, it was determined that
the controlled  release of the floodwater into the adjacent Cuckel's     Fj    2 Controlled release offloodwater
Brook would not negatively impact its water quality. By September    jnto Cuckers Brook at a rate averagjng
28, approximately 152 million gallons of floodwater had been         52oo gallons per minute, at a location close
discharged to  the brook (Figure 2) using generator-powered pumps   to the former sluice gate discharge point.
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on a swamp buggy. Throughout the controlled discharge, Cuckel's Brook and the connecting Raritan River were
monitored to ensure downstream water quality and communities were not adversely affected. The remaining 62
million gallons of standing water was primarily captured by the site's stormwater management system, with
lesser volumes evaporating or infiltrating to groundwater.

The potential for a surficial release or catastrophic failure of the
berms surrounding impoundments 1 and 2 was a concern during the
flood (Figure 3). These impoundments are located in the site's south
area, approximately 700 feet from the river and outside of the site's
flood control berm. Unreinforced earthen berms were constructed
around the two adjacent impoundments in the mid 1900s to contain
waste and control floodwaters. Before the floodwaters receded,
surface water samples were collected from standing water in the
vicinity of the impoundments and from downstream  points of the
Raritan River. Results from the post-flood surface water sampling
and berm inspections indicated that a significant release did not
occur.
                                                                  Figure 3. Area comprising impoundments 1
                                                                  and 2 that remained flooded two days after
                                                                  the peak of Hurricane Irene flooding.
Due to the elevated floodwater levels and loss of electrical power,
the site's groundwater extraction system was shut down for
approximately 30 days. Post-flood modeling estimated a
contaminant travel distance of approximately 160 feet during the 30-day shutdown, with ultimate recapture after
the system was restarted.
Based on an updated flood hazard map for the site (Figure 4), EPA approved a flood emergency preparedness
plan (FEPP) in March 2012 that provides control measures and procedures to protect the site, personnel and
equipment. The FEPP includes guidelines for issuing flood alerts, warnings and emergencies as well as
security procedures,  evacuation plans and procedures. Soon thereafter EPA approved a flood management
and response plan (FMRP) that identifies facility operational management and response procedures required
for flooding. The FMRP includes inspection and maintenance procedures for flood preparedness, pre-flood
preparations and post-flood conditions such as site entry,  recovery and restoration.
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                          B^K. -.-         •%*&*,> V\l,  '•   -
                                        •

                                                                 SITE BOUNDAR

                                                                 BASE FLOOD ELEVATIONS (NAVD 86 FT)

                                                                 WATER FEATURES

                                                                 FLOOOWAY (SEE REFERENCES*

                                                              FEMAFLOOD HAZARD AREAS

                                                                'I 500 YEAR FLOQDPLAIN (0 2*> ANNUAL CHANCE
                                                                 A- 1QQ YEARFIQOOPLAIN -<1%ANNUAL CHANCE)

                                                                 AE -BASE FLOODPLAIN WITHIN THE 100 YEAR FLOODPLAIN

                                                                 X -AREA OF MINIMAL FLOOD HAZARD
           Figure 4. Flood hazard map illustrating the American Cyanamid site's location within both the
           100-year and 500-year floodplains, with southeastern portions of the site lying within the Raritan
           River floodway.
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Implementation of the FEPP and FMRP, which have been updated several times to account for changing
project aspects and site conditions, has been integral to the site's recovery and to measures being taken to
address flood-related vulnerabilities. Following Hurricane Irene, a new drum storage area was built so that
containerized wastes could be stored outside of the flood hazard area. In the north area, the sluice gate was
repaired to enable rapid site drainage and a 360-foot damaged portion of the flood control berm was restored;
the associated spillway was reinforced with concrete-grouted riprap. Also, onsite security and staff trailers were
relocated to a non-contiguous portion of the site located outside the flood hazard area, and a contract was
secured for accelerated access to an outboard motor-equipped boat to aid future flood emergency/recovery
efforts. To assure electrical power is retained during future storms, critical onsite electrical infrastructure was
raised to elevations 5 feet higher than Hurricane Irene flood levels.

The site's groundwater extraction system has also been
adapted for the increased frequency of major flood events.
Both of the existing turbine  pumps used to extract groundwater
for offsite treatment were replaced with submersible pumps
designed to allow for uninterrupted pumping during future
floods. In April 2012, an interim onsite groundwater treatment
system was constructed to treat groundwater captured by a
collection trench intercepting discharges to the Raritan River.
The treatment system was constructed at an elevation more
than 1  foot higher than the flood levels experienced  during
Hurricane Irene (Figure 5).
                                                            Figure 5. Elevated groundwater treatment plant
                                                            constructed as part of an EPA removal action; the
                                                            treatment process includes metals precipitation,
                                                            filtration and carbon adsorption.
 Adaptation measures implemented to reduce the
vulnerabilities of impoundments 1 and 2 included installing
new HOPE covers on the impoundments to reduce the
potential for waste mobilization during floods, as well as
reinforcing the berms to increase their strength and prevent

flood-related scouring. A high-strength, ultraviolet-stabilized,
multi-layered synthetic matting with a fiber matrix material
(commonly known as a turf reinforcement mat [TRM]) was
installed on the berm banks to serve as a soft armor for erosion
control and vegetation stability (Figure 6). The TRM is
designed to withstand water velocities in  excess of 8  feet per
second.

Recent selection of a remedy also reflects adaptations to
account for potentially increased frequency of major flood
events.  In September 2012, the remedy for operable  unit
(OU)4 was  selected to address six impoundments, site-wide
soil and groundwater. The remedy is currently in the design
phase and involves in situ solidification/stabilization followed
by construction of an impermeable multi-layered cap  on over
60 acres and a 2-foot soil cap on more than 130 acres. The
record of decision requires all engineered caps to be
designed and constructed to withstand effects of a 500-year flood event, at a minimum. In addition to
withstanding direct effects of flooding, the OU4 engineered caps are required to be designed and constructed to
ensure resilience to  indirect climate/weather hazards posing potential threats, such as inadequate drainage,
slope instability, erosion, freeze/thaw cycle effects and altered surface vegetation.
                                                            Figure 6. TRM strips approximately 6.5 feet wide
                                                            deployed vertically along the outer portion of the
                                                            berms surrounding impoundments 1 and 2 and
                                                            anchored with metal pins prior to revegetation.
A major goal of the OU4 remedial design is to minimize loss of the site's floodwater storage capacity so that
flooding of downstream communities is not exacerbated. Potential measures include constructing a natural
stormwater management system and removing the site's flood control berm, which would increase the flood
storage capacity by over 200 million gallons during more common flood events. The OU4 remedial design as
well as general site operations were not modified due to experiences associated with the more recent Hurricane
Sandy along the New Jersey coast, which generated less than three inches of precipitation at this site.
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Remedy Performance: Remedy Resilience to Flooding at the Rocky Mountain Arsenal

Contributed by Greg Harareaves. U.S. Environmental Protection Agency, Region 8

The effects of heavy rainfall and associated flooding in and around Denver, Colorado, in September 2013
prompted close monitoring and frequent inspection  of containment and treatment remedies at the Rocky
Mountain Arsenal. Since the 1970s, cleanup of this  National Priorities List site has involved 31 projects
addressing approximately 3,000 acres of soil,  15 groundwater plumes and nearly 800 structures. Flood-related
vulnerabilities of highest concern focused on two capped hazardous waste landfills covering 84 acres and
approximately 450 additional acres containing six RCRA-equivalent evapotranspiration covers.

The former arsenal encompassed 17,000 acres (27 square miles) used by the U.S. Army to manufacture
chemical warfare agents and incendiary munitions during World War II.  From 1946 through the 1980s, portions
of the arsenal were leased to companies manufacturing industrial and agricultural chemicals. Various waste
products were stored, handled or disposed on the site, and solid waste was disposed in onsite burn pits,
sanitary landfills, basins and trenches. As a result, over 600 potential contaminants were identified in soil and/or
groundwater, with highest contamination relating to  organochlorine pesticides, heavy metals, agent-degradation
products and manufacturing byproducts, as well as  chlorinated and aromatic solvents. The U.S. Army and Shell
Oil Company maintain the capped  landfills and RCRA-equivalent covers, which blend with the surrounding
short-grass prairie land  designated as the Rocky Mountain Arsenal National Wildlife Refuge. The 15,000-acre
refuge, which is managed by the U.S. Fish and Wildlife Service (USFWS), includes areas where cleanup
activities were completed.

Soil remediation design focused on interrupting the  contaminant exposure pathways by: (1)  placing the most
contaminated soil (and structure demolition debris)  in two onsite RCRA Subtitle C landfills, and (2) consolidating
less contaminated soil and structure debris where excavation was infeasible and constructing six RCRA-
equivalent covers. Each landfill base includes two 3-foot compacted  clay layers with composite liners, leachate
collection systems, and composite  leak detection and  collection systems.  Due to higher toxicity of waste in one
landfill, its base liner includes a third 3-foot compacted clay layer and geosynthetic liner system, as well  as a
second leak detection/collection system. The final caps include: (1) a bottom layer of crushed concrete to
prevent biointrusion and promote gas venting, (2) geosynthetic membranes, (3) a 4-foot-thick rock-amended
soil layer, (4) a diverse mix of vegetation, and (5) a  system of drainage channels constructed of articulated
concrete block.
The six RCRA-equivalent covers use evapotranspiration technology
with a capillary barrier, rather than geosynthetic materials. This
design aims to allow zero percolation into underlying waste, prevent
biointrusion, control erosion by wind and water, and minimize
ponding. Each cover consists of four layers containing (from bottom
to top): (1) 16 to 18 inches of crushed concrete serving as a biota
barrier, (2) 1 to 3 inches of pea gravel (or in one case nonwoven
geotextile) to create a capillary barrier, (3) 48 inches of soil, and (4)
a diverse mix of vegetation. Each cover system includes a network
of drainage channels constructed of concrete and grass-lined
swales.

Construction of the caps and covers was completed in 2010.
Between September 9 and 16, 2013, more than 15 inches of rain
fell in the Rocky Mountain front range, which is equivalent to the
area's average precipitation in one year. Gauges at the arsenal
measured more than 8.2 inches of rain, with 3 inches falling on
September 12 alone. The National Oceanic and Atmospheric
Administration considers the precipitation a 500- to 1,000-year
storm event.
Figure 1. Overflow of the arsenal's network
of stormwater holding ponds due to record-
breaking rainfall and subsequent rupture of
the Havana Ponds dam used for controlled
release of the stored  water.
On September 12, stormwater surging onto the arsenal caused a
breach of the downgradient Denver-owned Havana Ponds dam
inside the wildlife refuge (Figure 1). Associated currents carved an 8-foot-deep gully through the refuge and
washed out roads, trails and other local infrastructure. More than 400 acres of the refuge were submerged
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during peak flooding, and billions of gallons of water from the South
Platte River watershed (including the arsenal) flooded surrounding
areas. The U.S. Army pumped out water that accumulated behind a
former railroad embankment nearby, and the USFWS opened
valves to relieve pressure on stormwater holding ponds within the
refuge.

Overall, the arsenal suffered more than $20 million in damage
caused by the flooding. Post-storm assessments indicated that the
two capped landfills were relatively resilient to the flood; both were
designed to withstand a 1,000-year, 24-hour storm event. During
the flood, sheet flow from the rock-amended soil on the RCRA-
Subtitle  C landfill caps drained to the concrete block channels as
anticipated, with minimal development of erosion rills (Figure 2) and
only minor sediment accumulation at the channel ends (Figure 3).
Additional sediment accumulated in leachate-riser control buildings
above one landfill but caused no damage to the instrumentation,
pumps or auxiliary systems. Small graders were used to remove the
accumulated sediment within one week of floodwater peak.

The RCRA-equivalent covers also performed effectively during the
flood. Their low slopes helped minimize formation of rills or gullies,
and sheet flow effectively drained to the concrete channels that
directed stormwater to surrounding drainage basins. These
channels had been designed to withstand a 100-year 24-hour storm
event. Associated sediment accumulated primarily outside the
cover perimeter, at low points on an access road with additional
drainage channels.
Figure 2. Rill erosion at the capped
landfills, primarily on access roads.
 Figure 3. Stormwater runoff carrying
 loose sediment, which settled within
 downgradient ends of the concrete
 drainage channels.
Other onsite remedies also were monitored during the flood and inspected after floodwaters receded. Although
operation of the site's five groundwater treatment facilities ceased during electricity outages at the time of
flooding, the facilities suffered no physical damage due to their positions at elevations higher than peak
floodwater. Power outages similarly affected operation of skimming pumps and other equipment used to
recover dense non aqueous-phase liquid (DNAPL) recovery. Due to changing hydraulic conditions, the DNAPL
transfer pumps began  operating outside their design parameters as floodwaters continued to  rise. Future
groundwater monitoring is anticipated to reveal if the site's subsurface slurry walls remain intact and whether
groundwater capture/controls were adversely affected by the flood. Visual inspections indicated no damage to
the site's fencing and signage.

Long-term monitoring of the capped landfills, RCRA-equivalent covers and groundwater containment/treatment
systems will consider potential increases in frequency or intensity of future flood events, as well as potential
droughts and related indirect impacts, such as altered rates of evapotranspiration. Several components of the
cover designs are expected to maintain their long-term performance and resilience to climate  change. For
example, their biointrusion layers consist of highly durable material (recycled concrete from former Stapleton
Airport runways) with a minimum compressive strength of 2,000 pounds per square inch, weight exceeding 130
pounds per cubic foot, and resistance to moisture-induced degradation.

Also, erosion  controls for the RCRA-equivalent covers were designed to limit overland flow lengths to 500 feet,
which minimizes rill and gully formation. Their designs reflect an overall slope of 3 percent in a "broken back"
configuration  involving drainage channels cut through the covers (Figure 4). A total of 2.5 miles of drainage
channels, ranging from 150  to 2,246 feet in length, were  installed  at grades of 0.3 to  1 percent across the 450
acres. The covers'  ability to  withstand extreme wind and  precipitation and related erosion is reinforced by their
ground surface vegetation. It comprises a diverse mixture of shallow- and deep-rooted  native  plants intended to
maximize water removal and increase resilience to indirect effects of a changing climate; effects could involve
pathogen and pest outbreaks or land surface disturbances such as wildfires and wildlife overgrazing.
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             Figure 4. Broken-back design and low-slope drainage provided by 6-inch-diameter slotted
             pipe secured beneath 4 feet of soil overlain by concrete channeling; the September
             stormwater drained effectively through the channels, despite heavy saturation of
             surrounding soil.
The landfills' leachate collection systems and leak detection/collection systems are monitored monthly.
Monitoring of the RCRA-equivalent covers includes monthly collection of lysimeter data indicating percolation
rates, annual quantitative inspections of the vegetation, and visual inspections at least seven times each year
for erosion, burrowing animals and overall integrity. Total soil loss and/or settlement of each cover is monitored
through use of erosion monuments to help identify needed repairs relating to rills, gullies, excessive sheet
erosion, settlement and apparent ponding. In addition, data from a network of water-content reflectometers
placed within the soil profile of one cover are collected continuously and analyzed quarterly to monitor moisture
content and migration at 6-inch intervals throughout the 4-foot-thick soil layer.

Overall, the remedies performed as designed and their integrity was not compromised during this 500- to 1,000-
year storm event. Future monitoring will include considering the need for vegetation replacement in any areas
suffering from an altered climate. Additionally, the USFWS intends to prepare a comprehensive conservation
plan and an environmental impact statement for the refuge, which may include wildlife and habitat management
practices in light of possible climate change and declining precipitation.

Remedy Design: Long-Term Protective Measures Against Storms and  Flooding at Allen Harbor
Landfill

Contributed by Christine Williams, U.S. Environmental
Protection Agency Region 1

The U.S. Navy, working with EPA and other federal and
state partners, integrated shoreline armoring structures,
including a  line of riprap, wetlands and a seawall  into the
remedial design of a coastal  landfill at the former  Davisville
Naval Construction Battalion Center (NCBC) Superfund site.
The structures are designed  to protect the landfill  face from
erosion through wave action, tidal forces and storm surges  in
the adjacent Allen Harbor. The harbor is located on the
western shore of Narragansett Bay, Rhode Island, and
surrounds the landfill on three sides (Figure  1). A  3-foot deep
multimedia cap installed  concurrently reduces the potential
for leachate generation from precipitation, while its
placement at the 100-year flood elevation level ensures its
continued integrity during smaller, more frequent storm and
flooding events. The storm mitigation measures are
expected to provide long-term protection for human and
ecological exposure to landfill contaminants with minimal
contaminant migration into Allen Harbor.
                                                          Figure 1. Allen Harbor Landfill boundary and its
                                                          proximity to Allen  Harbor. Riprap protects the
                                                          landfill face.
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The 15-acre Allen Harbor Landfill was used for the disposal of waste by NCBC Davisville and the Naval Air
Station Quonset Point from 1946 to 1972. Materials disposed of at the landfill included municipal-type waste,
construction debris, rubble, preservatives, paint thinners, solvents, polychlorinated biphenyls (PCBs) from
transformers, fuel oil, asbestos, ash, sewage sludge and waste fuel  oil. The landfill was closed in 1972 with the
placement of a discontinuous 2-foot-thick soil cover over the landfill  materials.

An investigation by the Department of Defense in 1984-1985 under  its Installation Restoration Program
indicated that surface water, sediment and shellfish samples collected from Allen Harbor were contaminated
with volatile organic compounds (VOCs), PCBs and metals. The Navy completed the remedial investigation (Rl)
in 1996. Groundwater and soil samples from the landfill area, as well as sediment samples from Allen Harbor
collected during the Rl, indicated elevated concentrations of VOCs and semi-VOCs, polycyclic aromatic
hydrocarbons (PAHs), pesticides, PCBs and metals.
                                                                                    Final Grade
                                         14"
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The potential for leachate generation,
erosion of the landfill face, contaminant
transport from the erosion and overland
runoff to intertidal sediment were the
primary concerns considered in selecting
the remedy. A multimedia cap was chosen
for its capacity to reduce runoff and
erosion, decrease the potential for
infiltration of precipitation, and prevent
human and animal contact with
contaminants in site surface soil. The cap
is composed of several layers (Figure 2): a
12-inch bedding and gas transmission
layer directly above  the waste; a
Bentomat® geosynthetic clay liner, which
consists of two layers of geotextiles
surrounding low-permeability sodium
bentonite and needle-punched together to
increase internal shear resistance; a
textured 40-mil VFPE (very flexible
polyethylene) geomembrane liner; a 16-
inch drainage layer;  a 14-inch barrier protection layer above a geotextile barrier; and a 6-inch vegetative
support layer.
                                         12"
                                                       Bedding/Gas Transmission Layer ' '•.•  ; V
                                                            Existing Waste
                                                                                    Geotexllle
                                                                                    Geomembrane
                                                                                    Geosynthelk Clay Liner
                                         Figure 2. Multimedia cap layer composition: bedding and gas
                                         transmission layer covered with a geosynthetic clay liner and
                                         geomembrane, a drainage layer covered with a geotextile, a barrier
                                         protection layer, and a soil layer to support vegetation growth.
The multimedia cap was constructed in areas above the 100-year
flood elevation, at 14 feet above mean sea level (MSL) and higher,
to avoid compromising the long-term effectiveness of the cap from
hydrostatic pressure on the liners during floods. The remainder of
the landfill is covered with a soil cap (Figure 3). To construct the
soil cap, the original soil cover installed in 1972 was regraded, and
an additional 18-inch common borrow fill layer was emplaced
along with a 6-inch layer to support vegetation. Sediment dredged
from the entrance to Allen Harbor was used as grading material
whenever possible.

The multimedia cap and soil cap were graded at least 3 percent
to promote precipitation runoff,  and were seeded and vegetated
(Figure 4). The site team determined that precipitation would run
off the slope and into the swales, which focus the  runoff into the
harbor. In addition, while groundwaterflow and the subsequent discharge of groundwaterfrom the landfill is to
Allen Harbor, the actual pathway that contamination follows is physically and temporally longer than previously
understood, and continued migration of contamination from the landfill to the nearshore has not been observed,
based on monitoring.
                 Figure 3. Soil cap at Allen Harbor Landfill
                 soon after completion and prior to planting
                 vegetation.
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The remedy also included placement of riprap along the entire
shoreline of the landfill to stabilize and protect the landfill from
erosion during tidal rise and storm surges. Riprap on the eastern
shore consists of 3,000-pound, 6-foot thick armor stones from about
15 feet above MSL to sea level, while stones at the same level on
the northern and southern shores have a 1- to 2-foot average
diameter. Smaller stones of an average of 3- to 6-inch diameter
were emplaced from sea level to about 15 feet below MSL. A layer
of small, 1-inch minimum size filter/bedding stone underlies the
riprap.
             •sf
                                                               Figure 4. Vegetation cover and monitoring
                                                               wells on Allen Harbor Landfill.
About 1.5 acres of intertidal wetlands on the eastern shore of the
landfill were restored by federal and state partners just before cap
construction was complete (Figure 5). The work consisted of removing all
common reeds (Phragmites australis) from the existing impacted wetlands,
replacing the adjacent polluted mudflat with a layer of rocks topped by dredge
spoils (from the harbor entrance channel), and planting deep-rooted cordgrass
(Spartina) on the modified surface. A seawall embedded up to  15 feet below MSL
and rising to a few feet above MSL separates the wetland from the harbor where
the potential for storm  surge is highest. The constructed wetland and seawall act
together to  trip waves and reduce energy reaching the riprap.

All remedial work was  completed in 1999, and long-term monitoring began in
2001. Groundwater, nearshore and wetland sediment, shellfish and landfill gas
are monitored annually to evaluate the stability of the groundwater plume and
verify the absence of unacceptable risks at potential exposure  points along the
landfill shoreline. The progression of wetland development is also monitored
annually. A habitat evaluation in 2010 indicated that plants and salt marsh organisms established well, though
vegetative growth in one section of the wetland is stressed. Navy inspections during storm events indicated that
waves have direct impact along this section of the marsh.

A recent site evaluation in 2013 indicated that the multimedia cap and shoreline armoring structures appear to
be functioning as expected, have not been impacted by weather events and will continue to prevent exposure to
landfill contaminants into the future. While the seawall on the eastern shore of the landfill was designed to be
inundated daily during high tide, the riprap has not been breached at its highest point, and settlement has not
presented an issue.

The Allen Harbor Landfill currently belongs to the Town  of North Kingstown,  which plans to use the  property in
the future for open space/passive recreation.
Figure 5. Wetland
under construction in
front of the landfill cap.
  Resources
  EPA Websites:
         Climate Change Impacts and Adapting to Climate Change
         EPA offers this website as a comprehensive source of information about climate change impacts
         and adaptation in major regions of the United States and in sectors such as ecosystems, energy
         and water resources. It also provides an overview of the concepts involved in climate change
         adaptation and links to tools for adaptation planning.

         Climate Change Indicators in the United States
         EPA worked with other federal agencies, universities, nongovernmental organizations and
         international institutions to compile a set of indicators that track signs of climate change. The
         indicators relate  to the categories of greenhouses gases, weather and climate, oceans, snow and
         ice, and society and ecosystems. To date, 26 indicators have been identified; background
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          information and trends for the indicators are available on this website. A comprehensive description
          of this effort to track climate change signs is provided in EPA's report, Climate Change Indicators in
          the United States, 2012 (EPA 430-R-12-004).

          Superfund: Climate Change Adaptation
          This area of EPA's Superfund website discusses adaptation in context of site remediation, provides
          key background information and tools, and describes adaptation steps underway within the
          Agency's national  Superfund program. Related information resources are available to help project
          managers and other stakeholders evaluate a site's potential vulnerabilities and implement
          adaptation measures that can increase remedy resilience to climate change impacts.

  New Planning Tool:

  Climate Change Adaptation Technical Fact Sheet: Groundwater Remediation Systems
  As the first in a series, this fact sheet addresses adaptation forgroundwater remediation systems. It is
  intended to serve as a planning tool by: (1) providing an overview of potential climate change vulnerabilities
  of groundwater remediation systems, and (2) presenting possible adaptation measures that may be
  considered to increase a groundwater remediation system's resilience to climate change  impacts. The
  concepts are provided in context of Superfund projects but may apply to cleanups conducted under other
  regulatory programs or through voluntary efforts.
        EPA is publishing this newsletter as a means of disseminating useful information regarding innovative and
      alternative treatment technologies and techniques. The Agency does not endorse specific technology vendors.

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