&EPA
United States
Environmental Protection
Agency
TOOLKIT FOR PREPARING CERCLA
RECORDS OF DECISION
SEPTEMBER 2011
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Environmental Protection
m m United
Agency
TOOLKIT FOR PREPARING CERCLA
RECORDS OF DECISION
This effort is the culmination of a multi-year collaboration with the Department of the Navy (DoN) to
ways to produce higher quality and more user-friendly Records of Decisions. EPA wishes to acknowledge the
DoN for its unflagging assistance, and technical support, especially the graphics production.
This product has significantly improved through those who have worked with EPA over the and EPA
gratefully acknowledges their contributions.
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TOOLKIT INTRODUCTION
This toolkit consists
of sixteen exhibits
and each includes a
"Recommended
Toolkit Tip
to help improve the
quality and transparency
of data presentation in a
Record of Decision.
This document provides guid-
ance to Regional staff regarding
how the Agency intends to inter-
pret and implement the NCR
which provides the blueprint for
CERCLA implementation. How-
ever, this document does not
substitute for those provisions
or regulations, nor is it a reg-
ulation itself. Thus, it cannot
impose legally binding require-
ments on EPA, sites, or the reg-
ulated community and may not
apply to a particular situation
based upon the circumstances.
Any decisions regarding a par-
ticular situation will be made
based on the statute and the
regulations, and EPA decision-
makers retain the discretion to
adopt approaches on a case-by-
case basis that differ from the
guidance where appropriate.
2See for example 40 CFR
300.400 and the guidance docu-
ment entitled: "A Guide to Pre-
paring Superfund Proposed
Plans, Records of Decision,
and Other Remedy Selection
Decision Documents" (OSWER
9200.1-23P), July 1999.
This document provides Remedial Project Managers (RPMs) with a resource to help improve
the public transparency and understanding of Superfund Records of Decision (RODs)
for remedy decisions developed in accordance with the Comprehensive Environmental
Response, Compensation, and Liability Act (CERCLA)1 using communication tools de-
signed to enhance the decision document's presentation (Exhibits 1-16). This document
provides suggestions on means to convey information graphically and visually in a ROD
or in a separate outreach document. By using these tools, RPMs may help clarify the
selected remedy (Figure 1) and effectively convey information in a format that thoroughly
yet concisely presents the full rationale for the remedy decision. These tools are meant
Figure 1 to supplement the ROD decision document, not replace
it. The suggestions or tools in this document do not
substitute for the statutory or regulatory requirements for
a ROD or for related guidance documents2.
The ROD should be a defensible, stand-alone
document that memorializes the remedy decision in an
appropriate level of detail, as discussed in EPAs ROD
Guidance. Sometimes, in attempts to be all inclusive
or overly thorough, a ROD includes extraneous inform-
ation or provides an excessive amount of detailed
information from previous documents. This may inad-
vertently affect the public's ability to understand the ROD.
RPMs may be able to summarize the key facts from prior site-related documents and use
the tools described herein to enhance the decision document's presentation to provide a
more succinct and understandable ROD. For example, by using summary graphics, figures,
and tables, supported by appropriate text, an RPM may be able to better illustrate the data,
analysis, and rationale to better explain the remedy selected in the ROD. Because there
is no "one size fits all" template, it is generally important during development of a ROD to
include the level of detail recommended by EPAs ROD Guidance and consider the use of
streamlining and visualization tools for better site-specific data or information presentation.
The example exhibits presented in this document track the EPA ROD
outline as provided in the "A Guide to Preparing Superfund Proposed
Plans, Records of Decision, and other Remedy Selection Decision
Documents" (OSWER 9200.1-23P) July 1999, on page 6-2. Each
exhibit provides recommended tips that suggest how and where to
consider including tools like tables and graphics in a ROD. These
recommended streamlining and visualization tools may also be
effective in the preparation of other documentation related to the
CERCLA remedy selection process, such as Remedial Investigations and/or Feasibility
Studies.
This document is designed to be viewed electronically. This format allows the reader to
zoom into the detail presented in the color graphics. Please note that some reformatting
may be required for printing.
EPA plans to create a web site that will provide additional information on available
visualization and decision support tools (i.e., software packages). These support tools
often can be used to present data/ information similar to the exhibits in this document.
The web site is intended to provide a resource of available free-ware and commercial
computer software. The data visualization tool listing will not provide endorsements
or recommendations of specific resources but instead will provide potential users with
examples of tools available and their stated applications. EPA also intends to provide
a series of documents on Conceptual Site Models designed to discuss the context for
potential use of visualization tools. The science supporting data visualization is advancing
rapidly and we anticipate the web site will continue to capture these advances.
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TOOLKIT EXHIBITS
Exhibit 1: Road Map of the Key Elements of Remedy Selection
Exhibit 2: Data Certification Checklist for RODs with Multiple Operable Units/Sites
Exhibit 3: Site Layout and Photographs
Exhibit 4: History of Site Investigations and Actions
Exhibit 5: Nature and Extent of Contamination
Exhibit 6: Conceptual Site Model
Exhibit 7: Current and Potential Future Land and Resource Uses
Exhibit 8: Risk Assessment Summary Tables
Exhibits: Basis for Action
Exhibit 10: Remedial Action Objectives for Chemicals of Concern Requiring Action
Exhibit 11: Summary of Remedial Alternatives
Exhibit 12: Evaluating Monitored Natural Attenuation as a Remedial Alternative
Exhibit 13: Comparative Analysis of Alternatives
Exhibit 14: Description of Selected Remedy
Exhibit 15: Expected Outcomes of the Selected Remedy
Exhibit 16: Optional Reference CD
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EXHIBIT 1. ROAD MAP OF SOME KEY ELEMENTS OF REMEDY SELECTION
Recommended
Toolkit Tip
Exhibit 1 visually displays
some of the possible graph-
ic tools that should be con-
sidered for incorporation
into a ROD; however, this
Exhibit itself should not be
included in the ROD. These
tools can help explain the
CERCLA remedy selection
decision process, and help
promote meaningful com-
munity involvement, which
typically is a key compo-
nent throughout that pro-
cess. Similar to a direc-
tional road map, there is
a starting point (CERCLA
Release) and a finish line
(Expected Outcomes) for
the site, with many key
stops along the way.
y
CERCLA Release
' Conceptual Site
Model
Risk Assessment
D
Basis for Action
Remedial Action
Objectives
I IHI
Remedial
Alternatives
Comparative
Analysis
Selected
Remedy
IHI
Expected
Outcomes
Conduct site investigation
activities to identify the CER-
CLA release, surface charac-
teristics, hydrogeology, nature
and extent, and fate and trans-
port mechanisms to develop the
conceptual site model (CSM).
Remedial Action Objectives
Risk Assessment
Future
Adult
Resident
Future
Child
Resident
^^^B
Subsurface
Soil
Groundwater
Subsurface
Soil
^^••1
Inhalation
Ingestion
Incidental
Ingestion
Inhalation
^^^m
C11-C22 Aromatic
Hydrocarbon
Fraction
VC
C11-C22 Aromatic
Hydrocarbon
Fraction
^^^^H
3,062 mg/hg
6.52 ug/L
3,062 mg/kg
NA
1.5E-04
NA
NA
2.92
0.0
1.30
2,92
NA
2.0E-05
NA
NA
0.711
0.0
0.159
0,711
Not
carcinogenic
1,9
Not
carcinogenic
3x102
0.0
3x10-'
Results of the risk assessment
are used to identify media and
chemicals of concern (COCs)
warranting a response action
based on current and potential
future land and resource use.
Refine the CSM to identify
the current and potential
future land and resource
uses and potential exposure
pathways for risk evaluation.
Remedial alternatives are devel-
oped for the media and COCs
warranting a response action.
Remedial Alternatives
Develop Remedial Action Objec-
tives (RAOs) and cleanup levels
to address all media and COCs
that warrant a response action.
D Basis for Action
1— Mo Action
2-MNA/LUCs
3-ERD using existing
Horizontal Well and
Downgradient ERD
Injections / Monitoring /
LUCs
None
MNA
LUCs
Enhanced Anaerobic
Bioremediation through
Horizontal Well
Enhanced Anaerobic
Bioremediation via
Downgradient Injections
LUCs
Allow the COCs to breakdown naturally over time
Groundwater monitoring and reporting to assess the
progress of natural attenuation over time
LUCs to prevent exposure to groundwater and
petroleum hydrocarbon-impacted soil
Injection of electron donors through existing
horizontal well to stimulate anaerobic biodegradation
of CVOC source by reductive dechlorination
Injection of electron donors in wells downgradient
from horizontal well, upgradient of Courthouse Bay,
to stimulate anaerobic biodegradation of CVOCs by
reductive dechlorination and minimize migration of
CVOCs to Courthouse Bay
LUCs to prevent exposure to grouncfwater and
petroleum hydrocarbon-impacted soil
Capital Cost
Annual operation and
maintenance (O&M)
Total Present-Worth
Timeframe
Capital Cost
Annual O&M
Total Present-Worth
Timeframe
Capital Cost
Annual O&M
Total Present-Worth
Timeframe
$0
$0
$0
30 years
$13,500
$48,249
$763,736
30 years
$854,751
$48,295
$1,946,816
20 years
Conceptual Site Model
Potential Risk to Future Resident: ingestion of Groundwa
*W—
~rr
Horizontal Well
- Groundwater Flow Direction
Location of Existing/Former UST
Hazmat Storage
Vehicle Washdown Areas
Operable Unit 21
TCE Concentrations
^H 50 < x < 1 00 ^g>L
•• 5 < x * 50 (jg'L
^ 2 8 < x < 5 M3/L
Human
Health
Subsurface soil
Current or potential
drinking water resource
Sediment/Surface water
Subsurface soil
Sediment/Surface water
Recreational & Training
No unacceptable risks
Mot applicable
Mon-cancer hazard index > 1
Cancerrisk >10"4
Cancerrisk>10"4
WCL exceedance
Vinyl chloride
No unacceptable risks
No unacceptable risks
Not applicable
No unacceptable risks
WCL exceedance
Cancerrisk >10"4
Mot applicable
Mot applicable
Remedial alternatives are evaluated
against the nine criteria and one
another for a comparative analysis.
Legend
* Monitoring Well
Extent ofTCE Exceed
B Extent of VC Exceeda
Extent of DCE Exceed
Extent of Benzene Exc
IngestionofVOCSin
groundwater under potable
use scenario
Direct exposure to
Detroleum hydrocarbons in
soil under residential use
scenario and leaching
sciential to groundwater
Restore groundwater quality based on the
classification of the aquifer as a potential source of
drinking water and to prevent human ingestion of
water containing COCs at concentrations above
NCGWQS or MCL standards, whichever is more
stringent until cleanup levels have been obtained.
Prevent future residential exposure to petroleum
hydrocarbon-contaminated soils above the NC HWS
SSL and minimize transport to groundwater.
Air sparge
system
Operate system until groundwater cleanup levels are met
[expected 5 years) to achieve UU/UE.
Maintain LUCs and LTM until groundwater COCs are at or
below cleanup levels for four consecutive monitoring events
to establish UU/UE.
Maintain LUCs on soil for continued industrial landuse.
The components of the Selected Remedy mitigate
risk to achieve RAOs consistent with current and
potential future land and resource uses.
Comparative Analysis
Based on the comparative analysis, a remedy is
proposed, then after opportunity for public com-
ment, selected that meets the threshold criteria and
achieves RAOs.
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EXHIBIT 2. DATA CERTIFICATION CHECKLIST FOR RODS WITH
MULTIPLE OPERABLE UNITS/SITES
ROD Section
Declaration
Data Certification Checklist
Recom mended
Toolkit Tip
For RODs addressing
multiple sites or Opera-
ble Units, a table may be
used to help the reader
locate important infor-
mation in each individual
ROD, such as information
for each recommended
element of the sam-
ple Data Certification
Checklist.
ROD Section Number
Data
Chemicals of concern and their respective
concentrations
Baseline risk represented by the chemicals of
concern
Cleanup levels established for chemicals of
concern and the basis for these levels
How source materials constituting principal
threats are addressed
Current and reasonably anticipated future
land-use assumptions and current and potential
future beneficial uses of groundwater used in the
baseline risk assessment and ROD
Potential land and groundwater use that will be
available at the site as a result of the Selected
Remedy
Estimated capital, annual operation and
maintenance (O&M), and total present worth
costs, discount rate, and the number of years
over which the remedy cost estimates are
projected
Key factor(s) that led to selecting the remedy
(i.e., describe how the Selected Remedy
provides the best balance of tradeoffs with
respect to the balancing and modifying criteria,
highlighting criteria key to the decision)
OU/Site1A-1 OU/Site1H OU/Site6A*
1.2
1.4
1.4
1.5
1.3
1.8
1.8
1.7
2.2
2.4
2.4
2.5
2.3
2.8
2.8
2.7
3.2
3.4
3.4
Not Applicable
3.3
Not Applicable
Not Applicable
Not Applicable
"no action is required for OU/Site 6A
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EXHIBIT 3. SITE LAYOUT AND PHOTOGRAPHS
Administrative Record Resources
ROD Section
Decision Summary
Site Name, Location, and
Brief Description
Recom mended
Toolkit Tip
Embedding regional and
base location images
as insets within a figure
showing the detailed site
layout often can effec-
tively consolidate infor-
mation previously dis-
played in several figures.
This type of comprehen-
sive graphic combined
with historic and current
site photographs, if avail-
able, can help provide
the reader with a better
understanding of the site.
The figure should present
accurate information on
the site boundary, current
conditions that encompass
the source(s), or release
area(s) and the extent of
contamination. As noted
in the 40 CFR 300.4,
CERCLA response actions
include "where a hazardous
substance has been dep-
osited, stored, disposed of,
or placed, or otherwise
come to be located."
Therefore, the extent of
contamination should not
be truncated by artificial/
physical boundaries (e.g.,
property line, roadways,
water bodies).
Synthesize Summarize
LEGEND
« Shallow Monitoring Well Location
• Deep Monitoring Well Location
Site 5 Waste/BuVnt Soil Area
|C3 Site 5 Boundary
^1 Lower Drainage
I—I Upland Drainage
Existing Wetland Area A
Former Building
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EXHIBIT 4. HISTORY OF SITE INVESTIGATIONS AND ACTIONS
ROD Section
Decision Summary
Site History & Enforcement
Activities
Recom mended
Toolkit Tip
To enhance the presen-
tation of the site history
and enforcement activities
discussion, a summary table
and/or graphic depicting
previous investigations/act-
ions may be used to explain
how the site has been
adequately investigated util-
izing an appropriate sampl-
ing strategy. The level of
detail in a summary table
should be adequate to me-
aningfully supplement the
ROD's discussion of all pert-
inent investigation/action in-
formation as the site has
gone through the CERCLA
process.
Including a figure can be an
effective way of illustrating
the sample locations with
good spatial coverage, app-
ropriate medium, and rele-
vant analysis groups based
on the CERCLA release or
threat of release. Emerging
contaminants (e.g., perchlo-
rate, 1,4-dioxane) should
not be overlooked.
For extensive site histories
where a text summary may
be more appropriate, the
use of a time-line can help
present a graphic depic-
tion of the CERCLA inves-
tigations/actions that have
occurred.
Administrative Record Resources
Proposed Plan
sitenschooiofMiisicpiatingShop
Feasibility Study
Technical Memorandum te 11 - school of Music plating shop
II Revised Human Health Risk Assessment
SRI Addendum
Naval Amphibious Base Little Creek
Virginia Beach, Virginia
Pwraatw
Department of the Navy
Naval Facilities Engineering Command
CH2MHILL
Supplemental Remedial Investigation
for Site 11
School of Music Plating Shop
Naval Amphibious Base Little Creek
Virginia Beach, Virginia
Decision Docunienr
Site 11: School of Miuic Plating Shop
Naval Amphibious Base Lillle Creek
Naval Facilities
Engineering Com man
Norfolk. Virginia
LANTDIV CLEAN Program
Interim Removal fiction
Final Closeout Report
Site 11 • School of Music Plating Shop
Naval Amphibious Base Little Creek
Norfolk, Virginia
Neva! Construction Battalion Center
Naval Facilities Engineering Command
Port Hueneme, California 93043-5000
il Investigation Report
ous Base Little Creek
Beach, Virginia
L PROGRESS REPORT
1 VERIFICATION STEP
aval Amphibious Base,
Little Creek
l-M USONM EVI AL .SERVK' US
snrfl WIIKELER v:
Livington, \*« ,(«>
(\iNlr.ii1 Sn247ll-Ji'J.|l 4NN
AKEK F-\VIlM»iMKNTAL, IT
iSMENT STUDY OF
IBIOU5 BASE, LITTLE CREEK
WIMIA
ATLANTIC DIVISION
NAVAL FACILITIES
ENGINEERING COMMAND
NORFOLK, VIRGINIA
Synthesize
Summarize
2 Decision Summary
«orvandEnforcementActivi
1984
Initial
Assessment
Study 1986
, — Confirmation
Study
• 1984
1994
1991
r Interim
Remedial
Investigation
Investigation /
Feasibility
study 1994
r Decision
Document
1994
2000
1999
National
\ US"ng
~ Screening
Level .
Ecological
Assessment
2001-2006
Investigation
1999 2001
2006 2007
Feasibility Proposed
Study Plan
2007 M
' ' r
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EXHIBIT 5. NATURE AND EXTENT OF CONTAMINATION
ROD Section
Decision Summary
Site Characteristics
Recom mended
Toolkit Tip
Comprehensive figures
may be used to sup-
port the ROD'S discus-
sion concerning the cur-
rent relationship between
potential sources, subsur-
face geology and hydro-
geology, and the lateral/
vertical extent and mag-
nitude of contamination.
The figures should reflect
any uncertainties in the
data presentation.
For sites with groundwa-
ter plumes or subsurface
contamination, a figure
can help portray an accu-
rate, detailed depiction of
both the horizontal and
vertical extent of contam-
ination, which can also
assist in better under-
standing the conceptual
site model.
Administrative Record Resources
j.1.2 Vfefland Surface Debris Delim
5.1 investigation Results
I
r
Synthesize
Summarize
-
' """
1=1 XJj^Siyf'™
> ' "''•i'" ".'."":""
Fijure 9
Ctll'jrinatcd S
-CHaiVlHILL
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EXHIBIT 6. CONCEPTUAL SITE MODEL
Administrative Record Resources
ROD Section
Decision Summary
Site Characteristics
Recom mended
Toolkit Tip
A comprehensive concep-
tual site model graphic
generally helps illustrate
the site layout, hydro-
geologic setting, source
area(s) and contami-
nated medium, fate and
transport mechanisms,
exposure pathways, and
potential current and
future receptors.
Current/Future Industrial Worker:
Inhalation of potential groundwater
ind
EH r=n r:s;.: -,.--j na rsn
Storm Sewer System
Trespasser Ingestion and Dermal Contact of Surface Water & Sediment; Ingestion, Deimal
Cornaa . & Inhalation of Surface Soil
Current Future Industrial Worker Ingestion of Groundwater;
Inlia'ation of Groundwater Vapors (Indoor Air); Ingestlon, Dermal
Contact. & inhalation of Soil
Future Construction
Worker: Dermal Contact of
Groundwater; inhalation of
Ground water Vapots;
Ingestion, Dermal Contact,
• I .=:'.,, ./ u
Synthesize
Summarize
Future Construction Worker
Ingestion, dermal contact and
absorption of groundwater,
sediment, and subsu
Terrestrial Flora and Invertebrates: Direct
contact and root uptake from surface soil, surfac
water, and sediment; Ingestion and direct contae
with surface soil, surface water and sediment
Benthic Dwelling and Aquatii
SJCA Non Site.
related
Sources
Current/Future Resident: Ingestion, -
dermal absorption and inhalation of
groundwater; Ingestion and de
absorption of surface soil; Inhalation
surface soil
Trespasser/Visitor: Ingestion anc
dermal con tact of surface water
and sediment; Inhalation and
dermal absorption of surface soil
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EXHIBIT 7. CURRENT AND POTENTIAL FUTURE LAND AND
RESOURCE USES
ROD Section
Decision Summary
Current and Potential
Future Land and Resource
Uses
Recom mended
Toolkit Tip
A map can be an extremely
effective tool for depicting all
onsite and adjacent land/
resource uses, including
recreational use of adjacent
surface waters and ground-
water classification for cur-
rent and potential future
use. Refer to page 7 of
"Summary of Key Existing
EPA CERCLA Policies for
Groundwater Restoration"
(OSWER Directive 9283.1-
33, June 26, 2009.) The
map can also help ensure
appropriate remedial action
objectives are identified for
the potential receptors.
Maps also can help show
consideration of land use
assumptions, relevant land
and resource management
plans, zoning maps, 20-year
development plans, reuse
assessments, and nearby
development activity. The
site layout figure or addi-
tional figures/photographs/
planning documents also
may be useful for depicting
current and potential future
land and resource uses.
Refer to page 2 of "Land
Use in the CERCLA Rem-
edy Selection process"
(OSWER 9355.7-04, May
25,1995.)
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EXHIBIT 8. RISK ASSESSMENT SUMMARY TABLES
Administrative Record Resources
ROD Section
Decision Summary
Summary of Site Risks
Recom mended
Toolkit Tip
Summary tables may be
used to help explain the
ROD'S discussion describ-
ing the risk assessment
procedures and to help
summarize the unac-
ceptable risks; the sum-
mary tables can include
information on receptor
scenarios, medium, expo-
sure pathways, chemicals
of concern, exposure point
concentrations, and tox-
icity values. These tables
should be supplemented
with cumulative risk sum-
mary tables to help ensure
all risk assessment consid-
erations discussed in EPA's
ROD Guidance (1999) are
addressed.
Summary tables can
help explain how the risk
assessment reflects current
toxicity values, risk assess-
ment methodologies and
guidance, and site condi-
tions (e.g., current residual
risk if interim actions were
taken). The tables also can
help explain how all appro-
priate exposure pathways
have been evaluated in a
manner that considers cur-
rent and potential future
use (e.g., indoor air expo-
sure, risk to future on-site
workers).
Synthesize Summarize
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EXHIBIT 9. BASIS FOR ACTION
ROD Section
Decision Summary
Summary of Site Risks
Recom mended
Toolkit Tip
Maps and tables can help
explain the results of the
risk assessment and to help
identify medium and chemi-
cals of concern (COC) war-
ranting a response action,
considering current and pot-
ential future land use. These
tools can help document the
appropriate risk manage-
ment decisions for risks
exceeding threshold criteria
and for chemicals of poten-
tial concern identified in
screening-level risk assess-
ments (e.g., comparison to
background, slight exceed-
ance of threshold criteria).
A summary table with sup-
porting text may be use-
ful in identifying the poten-
tial receptors, impacted
medium, land and resource
uses, and COCs warrant-
ing response action under
CERCLA A summary table
can help present the con-
centrations of COCs in each
medium and associated risk
factors may also be included
to illustrate the magnitude of
the threat to human health
and the environment posed
by the site. Graphics to help
explain the Basis for Action
can also assist in the ROD'S
discussion of the Remedial
Action Objectives (RAOs)
and the cleanup levels (see
Exhibit 10).
Legend
Monitoring Wei
Extent of TCE Exceedances
Extent of VC Exceedances
Extent of DCE Exceedances
Extent of Benzene Exceedances
Extent of Soil Contamination
Reasonably Antici pated
Receptor Media Land Use
Human
Health
Ecological
Surface soil
Subsurface soil
Groundwater
Sediment/Surface water
Surface soil
Subsurface soil
Groundwater
Sediment/Surface water
Residential
Residential
Current or potential
dri nki ng water resource
Recreational & Training
Habitat
No pathway
Habitat
Habitat
Chemical of Concern
No unacceptable risks
Arsenic
Benzene
TCE
cis-1,2-DCE
1,1-DCE
Vinyl chloride
No unacceptable risks
No unacceptable risks
Not applicable
No unacceptable risks
No unacceptable risks
Basis for Action
Not applicable
Non-cancer hazard index of 1 A
Cancer risk of 1.2x1 0'4
Cancer risk of 2.3 x10"3
Max concentration = 136 \iglL
(exceeding MCL of 70 |jg/L)
Max concentration = 34 |jg/L
(exceeding MCL of 7 |jg/L)
Cancer risk of 1.7 x1CT4
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
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EXHIBIT 10. REMEDIAL ACTION OBJECTIVES FOR CHEMICALS
OF CONCERN WARRANTING RESPONSE ACTION
ROD Section
Decision Summary
Remedial Action Objectives
Recom mended
Toolkit Tip
Where appropriate, it
may be helpful to use a
bullet format to present
the remedial action
objectives (RAOs) that
are established to add-
ress all unacceptable
current and reasonably
anticipated future risks
at the site. A bullet
format for the RAOs
can effectively present
qualitative statements. To
present the quantitative
site-specific cleanup levels
that need to be met for
each medium in order to
achieve the RAOs, it may
be useful to include tables
to list the chemicals of
concern (COCs) in each
medium warranting a
response action, their
respective cleanup levels,
and the basis for the
cleanup levels. A figure
also can be effective to
help illustrate the areas
within the site where
concentrations of COCs
exceed cleanup levels
and warrant action.
• 2 DECISION SUMMARY •
2.7 Remedial Action Objectives
The Navy, EPA, and VDEQ
concluded that remedial action is necessary to protect public
health, welfare, and the environment from actual or threatened releases of hazardous
substances in soil, shallow groundwflter, sediment, and surface water at Site 2. Site-specific
Remedial Action Objectives (RAOs) are as follows:
Waste, soil, and sediment (including sediment pore water):
• Prevent direct media contact with human and ecological receptors at concentrations that
pose unacceptable risks
• Prevent migration of contaminants through surface water runoff and erosion pathways
• Prevent or minimize transport of COCs from waste to site media
Shallow groundwater (including residual DNAPL):
• Reduce contaminant source mass to the maximum extent practicable
• Prevent activities that might cause migration of chlorinated VOCs in the Columbia
aquifer to the underlying Yorktown aquifer
• Prevent chlorinated VOC
sediment
migration from the shallow groundwater to surface water and
• Reduce chlorinated VOC concentrations in shallow groundwater to the maximum extent
practicable and prevent
exposure until concentrations allow for unlimited use and
unrestricted exposure (beneficial use scenario)
Surface water:
• Minimize degradation of surface water
The quantitative cleanup levels that need to be met to achieve the RAOs are presented in
Table 2-2 below.
TABLE 2-2
COCs and Cleanup Levels
^1 Chemical of Concern
Cleanup Level Basis for Cleanup Level ^1
Surface soil (mg/kg)
Antimony
Lead
Vanadium
Groundwater (ug/L)
1,1-DCE
cis-1,2-DCE
Napthalene
TCE
Sediment (mg/kg)
Chromium
"average site-wide concentration
26.4 Calculated risk-based value
400* Action Level
72 Background
7 MCL
70 MCL
170 Cacluated risk-based value
5 MCL
53 Background
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EXHIBIT 11. SUMMARY OF REMEDIAL ALTERNATIVES
ROD Section
Decision Summary
Description of Alternatives
Recom mended
Toolkit Tip
Remedial alternatives dis-
cussed in a ROD also may
be presented in a summary
table identifying the alterna-
tives, major components,
description (e.g., estimated
volume of excavation), costs
(capital, operation and main-
tenance, present worth, and
discount rate), and estimated
time frame to achieve reme-
dial action objectives (RAOs).
Such a table can help show
how the alternatives consid-
ered would each address the
risks at the site, consistent
with the basis for action and
RAOs. To accurately pres-
ent the "no action" alternative,
land use controls (LUCs)/ insti-
tutional controls (ICs) should
not be included, for example.
The tables can also include
text that presents the com-
mon elements and distinguish-
ing features that are unique to
the alternatives and that may
directly affect the implementa-
tion, operation, or outcome if
selected as the remedy.
Refer to Institutional Controls:
A Guide to Planning, Imple-
menting, Maintaining, and
Enforcing Institutional Con-
trols at Contaminated Sites
(EPA, 2010). A summary table
should include appropriate use
of terminology for LUCs/ICs, if
applicable.
Administrative Record Resources
Development and Evaluation of Remedial
Alternatives
5.1 General Response Actior
52 Identification and Evaluation of Remedial Approaches
S3 Development and Evaluation of Remedial Alternatives
IF
Synthesize Summarize
| TABLE 5 - REMEDIAL ALTERNATIVES 1
Alternative
No Action
No action for contaminated
soil with no restriction on
activities.
Biostimulation and Off-
Site Disposal
Excavation and stockpiling
of contaminated soil foron-
site ex-situ treatment
followed by backfilling and
site restoration.
Excavation and Off-Site
Disposal
contaminated soil followed
by off-site disposal,
backfilling, and site
restoration.
Groundwater
No Action
No action for contaminated
groundwater with no
restriction on activities.
MNA and LUC/ICs
Groundwater monitoring to
access concentrations of
COCs until performance
standards have been
achieved via natural
attenuation
Components
-Existing soil
-Excavation of soil
-On-site ex-situ
biostimulation
followed by off-site
disposal
-Site restoration
-Engineering
uontrois
-Excavation of soil
-Off-site disposal
-Site restoration
-Engineering
Controls
^^^m
-Existing
groundwater
-MNA groundwater
monitoring
-LUC/ICs
Description
-No action
-Excavation of an estimated 1 ,333 yd3 of soil. On-site
material will be evaluated for potential re-use for backfill
(it is estimated that only 1/3 of excavated material is
contaminated based on existing sample data)
-Collection of confirmation samples from the excavation
and of the uncontaminated soil for analysis of COCs to
verify performance standards are met
-Stockpiling of contaminated site soil and placement on
a treatment pad with physical controls (fencing and
signs) to prevent access and erosion and sediment
controls (silt fencing ) to prevent contaminant transport
-Mixing stockpiled soil with amendments (e.g. Commercial
fertilizer) and bi-weekly aeration to stimulate biological
degradation
-Periodic sampling of stockpiled soil until performance
standards are met followed by off-site disposal
-Mixing clean fill and uncontaminated site soil for backfill
and site restoration (repaying)
-Excavation of an estimated 1 ,333 yd3 of soil. On-site
material will be evaluated for potential re-use for backfill
(it is estimated that only 1/3 of excavated material is
contaminated based on existing sample data)
-Collection of confirmation samples from the excavation
and of the uncontaminated soil for analysis of COCs to
verify performance standards are met
-Stockpiling of contaminated site soil with physical
controls (signs) to prevent access and erosion and
sediment controls (silt fencing) to prevent contaminant
transport during waste characterization
-Waste characterization testing to classify the
contaminated soil for proper off-site disposal
-Mixing clean fill and uncontaminated site soil for backfill
and site restoration (repaying)
^^M^^^H
-No action
-Periodic groundwater monitoring (three existing wells
and one newly installed well) for natural attenuation
indicator parameters and reporting
-LUC/ICs to restrict access to the Surficial Aquifer so that
the potential exposure pathway to contamination would
remain incomplete until performance standards have
been achieved
-O&M of monitoring wells
Cost
No cost
Capital Cost:
$291,600
Annual O&M Cost: $0
Present-Worth Cost:
$291,600
Federal Discount
Rate: 3.5%
Timeframe: 2 years
Capital Cost:
$229,300
Annual O&M Cost: $0
Present-Worth Cost:
$229,300
Federal Discount
Rate: 3.5%
Timeframe: 1 month
^^^H
No cost
Capital Cost: $73,400
Annual O&M Cost:
$24,900
Present-Worth Cost:
$194,300
Federal Discount
Rate: 3.5%
Timeframe: 5 years
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EXHIBIT 12. EVALUATING MONITORED NATURAL ATTENUATION AS A REMEDIAL ALTERNATIVE
ROD Section
Decision Summary
Description of Alternatives
Recom mended
Toolkit Tip
A diagram may be a useful tool
if Monitored Natural Attenua-
tion (MNA) is considered as a
potential remedial alternative
or component of an alterna-
tive for groundwater; the dia-
gram can present the lines
of evidence contained in the
administrative record and dis-
cussed in the ROD which sup-
port an MNA approach at the
site. The diagram also can be
an effective tool for depicting
a clear and meaningful trend
of concentrations, figures of
groundwater concentrations
over time, and tables of geo-
chemical data. Other graphics
can help explain the estimated
time frame for MNA to achieve
cleanup levels, as well as com-
parable time frames which
could be achieved with active
restoration.
Tables and diagrams also can
be used to portray site-specific
data, such as the lines of evi-
dence for MNA, and summa-
rize the key points discussed
in the ROD's evaluation con-
tained in the Decision Sum-
mary: Description of Alter-
natives and Comparative
Analysis of Alternatives.
VOC Concentrations
900
--. 800
^ 700
•- 600
•I 500
2 400
| 300
5 200
100
0
u
•TCE
^
•cis-l,2-DCE
«Sr
Vinyl Chloride
Geochemical Parameters
Temperature (°C)
DO (mg/L)
pH (SU)
ORP (mV)
Ferrous Iron (mg/L)
Nitrate (mg/L)
Nitrite (mg/L)
Alkalinity (mg/L)
Chloride (mg/L)
Sulfate (mg/L)
Sulfide (mg/L)
TOC (mg/L)
Methane (ug/L)
Ethane (ug/L)
Ethene (ug/L)
18.7
1.2
8.2
31
0.5
Not Detected
1.2
600
57
12
0.8
4.5
24
Not Detected
Not Detected
17.4
0.25
7.5
-170
8.2
Not Detected
0.8
1,500
254
1.8
Not Detected
260
780
125
12.8
17.2
0.3
8.1
-123
2.1
Not Detected
0.7
1,400
195
8.4
0.1
48
342
97
5.4
Microbial Analysis (cells/mL)
Dehalococcoides
Desulfuromonas
Dehalobacter
Not Detected
Not Detected
2.81
350,000
23.6
45.1
5,000
1.54
6.45
TCE Concentrations Over Time
> Monitoring \Afell Locations
Groundwater Flow
Site Boundary
3 Monitoring \Afell Locations
Groundwater Flow
Site Boundary
Lines of evidence for MNA:
1. Historical groundwater and/or soil chemistry
data that demonstrate a clear and meaning-
ful trend of decreasing contaminant mass
and/or concentration over time at appropriate
monitoring or sampling points. (In the case of a
groundwater plume, decreasing concentrations
should not be solely the result of plume migra-
tion. In the case of inorganic contaminants, the
primary attenuating mechanism should also be
understood.)
2. Hydrogeologic and geochemical data that can
be used to demonstrate indirectly the type(s)
of natural attenuation processes active at the
site, and the rate at which such processes will
reduce contaminant concentrations to required
levels. For example, characterization data may
be used to quantify the rates of contaminant
sorption, dilution, or volatilization, or to demon-
strate and quantify the rates of biological deg-
radation processes occurring at the site.
3. Data from field or microcosm studies (conduct-
ed in or with actual contaminated site medium)
which directly demonstrate the occurrence of
a particular natural attenuation process at the
site and its ability to degrade the contaminants
of concern (typically used to demonstrate bio-
logical degradation processes only).
Use of Monitored Natural Attenuation at Superfund, RCRA
Corrective Action, and Underground Storage Tank Sites
(EPA, 1999)
Performance monitoring to evaluate biodegradation over time should
be included as part of an MNA alternative.
-------
EXHIBIT 13. COMPARATIVE ANALYSIS OF ALTERNATIVES
ROD Section
Decision Summary
Comparative Analysis of
Alternatives
Recom mended
Toolkit Tip
Various table formats using
summary text can be effec-
tive in complementing the
ROD's detailed discussion
of how each alterna-
tive compares with the
other alternatives and with
respect to the National
Oil and Hazardous Sub-
stances Pollution Contin-
gency Plan (NCP) nine
criteria. Tables can help
identify the distinguishing
element or factor that favors
one alternative above the
others and that supports
the rationale for selection of
the remedy explained in the
ROD. A graphic "consumer
report" style table may be
used to present the rela-
tive ranking in support of the
ROD'S text.
The NCP's two thresh-
old criteria must be met
for all alternatives except
"no action". If contingency
remedies are a compo-
nent of a remedial alt-
ernative, be sure to evaluate
them with respect to the
NCP criteria. Refer to "Guide
to Preparing Superfund Pro-
posed Plans, Record of
Decisions, or Other Rem-
edy Selection Decision Doc-
uments" (OSWER 9200.1-
23P, July 1,1999), Highlight
8-8, p. 8.10.
Administrative Record Resources
Synthesize Summarize
Protection of human health and the
environment
Compliance with ARARs
Primary Balancing Criteria
Long-term effectiveness and permanence
Reduction in toxicity, mobility, or volume
through treatment
00 •
• 00 •
$1.1 M S2.5M S1.9M S1.9M
Short-term effectiveness
Implementability
Present Cost
Modifying Criteria
State Acceptance
Community Acceptance
Ranking: • High O Moderate O Low
Rankings are provided as qualitative descriptions of the relative compliance of each alternative with the
criteria.
NC = No significant comments were received from Community Members
Yellow shading indicates selected remedy.
-------
EXHIBIT 14. DESCRIPTION OF SELECTED REMEDY
ROD Section
Decision Summary
Selected Remedy
Recom mended
Toolkit Tip
A figure typically is an
effective way to help
describe the Selected
Remedy discussion in the
ROD; a figure can be use-
ful to illustrate the remedy
components that address
all chemicals of concern
and medium requiring
action. For example, the
figures in this exhibit show
the groundwater treatment
area/soil removal area, pro-
posed injections points for
treatment, performance
and long-term monitor-
ing locations as well as
the estimated aquifer use
control boundary that will
be in-place until ground-
water cleanup levels are
achieved.
Legend
® Existing Monitoring Wells
• Estimated Injection Points
Q Estimated RA Monitoring Well'
® Estimated LTM Wells
5 Estimated Boundary Aquifer U
Groundwater Flow
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EXHIBIT 15. EXPECTED OUTCOMES OF THE SELECTED REMEDY
ROD Section
Decision Summary
Selected Remedy
Recom mended
Toolkit Tip
A summary table can be
a useful tool to supple-
ment ROD text by high-
lighting how the key com-
ponents of the Selected
Remedy are designed to
mitigate risk to achieve
remedial action objectives
consistent with current and
potential future land and
resource uses.
2.9.3 Expected Outcomes of the Selected Remedy
Current industrial land uses are expected to continue at Site 73 and there are no other planned
land uses in the foreseeable future, or for development of adjacent lands. Cleanup levels for the
Selected Remedy are based on unlimited use and unrestricted exposure. Exposure will be
controlled through land use controls/industrial controls (LUCs/ICs) until chemicals of concern
(COCs) in groundwater and soil are reduced to the cleanup levels. Table 2-5 summarizes the
unacceptable risk (media, pathway, receptor), the remedial action objectives (RAOs) identified
to address the risk, the remedy component intended to achieve the RAO, the metric that
measures the remedial action progress, and the expected outcome that the remedy will achieve.
TABLE 2-5
Expected Outcomes of the Selected Remedy
Risk
IngestionofVOCS
in groundwater
under potable use
scenario
Direct exposure to
arsenic in soil under
residential use scenario
and leaching potential
to groundwater
Transport ofVOCs
in groundwater to
surface water
Remedial Action Objective
Restore groundwater quality based
on the classification of the aquifer as
a potential source of drinking water
and to prevent human ingestion of
water containing chemicals of
NCGWQS or MCL standards,
whichever is more stringent until
cleanup levels have been obtained.
Prevent future residential exposure
to arsenic-contaminated soils
above the NC HWS SSL and
minimize transport to groundwater.
Minimize migration of chemicals of
concern in groundwater to surface
water.
Remedy
Component
Air sparge
system
LTM for MNA
LUCs/ICs
LUCs/ICs
ERD
biobarrier
LTM
LUCs/ICs
Metric
Operate system for up to 5 years or
until groundwater cleanup levels within
the radius of influence are met,
whichever is the shortest period.
Implement until each groundwater
chemical of concern is at or below its
respective cleanup level for four
consecutive monitoring events.
Maintain LUCs/ICs until chemicals of
concern in the soil are at such levels
that allow for unlimited use and
unrestricted exposure.
Maintain until chemicals of concern in
groundwater meet cleanup levels
Implement until each groundwater
chemical of concern is at or below its
respective cleanup level for four
consecutive monitoring events.
Expected
Outcomes
Achieve
exposure
Maintain
industrial use
Minimize
migration of
chemicals of
concern in
groundwater to
surface water
The air sparge system will be operated for up to 5 years or until the cleanup levels within the
radius of influence were met, whichever is the shortest period. System effectiveness will be
evaluated annually by comparison of current concentrations of COCs in treatment area
monitoring wells to pretreatment concentrations and the cleanup levels. The enhanced
reductive dechlorination (ERD) biobarrier wall will be maintained until groundwater COCs
concentrations have met the cleanup levels.
In accordance with LUC/IC objectives, groundwater use will be restricted to monitoring or
remedial purposes. Long-term monitoring (LTM) for Monitored Natural Attenuation (MNA) will be
conducted until each COC in groundwater is at or below its respective cleanup level for four con-
secutive monitoring events. The Navy and Marine Corps, in partnership with USEPA and the State,
will evaluate the discontinuation of monitoring of individual COCs that have met the cleanup levels
after four rounds based on site conditions. The results of LTM will be documented in an annual
monitoring report. When all COCs have achieved their cleanup levels for four consecutive
sampling events, site closure will be initiated. Once RAOs for this groundwater action have
been achieved, the Site 73 area is expected to be suitable for unlimited use and unrestricted
exposure for groundwater. Therefore, the Navy, USEPA, and NCDENR may agree for the
groundwater LUC/IC component of the Selected Remedy to be terminated at site closeout.
LUCs/ICs, restricting any potential future residential exposure to Impacted soils, will be
maintained until the concentration of COCs in the soil are at such levels that allow for
unrestricted use and unlimited exposure.
-------
EXHIBIT 16. OPTIONAL REFERENCE CD
Administrative Record File
Recom mended
Toolkit Tip
A hard copy ROD is the
official ROD and should be
placed in the Administrative
Record. An optional CD ref-
erence tool can be included
as a supplemental tool in
order to provide the reader
with immediate access to
Administrative Record files
referenced within the ROD.
A detailed reference table,
highlighting the key words
identified in the ROD text,
should be provided. Prior to
developing a reference CD,
stakeholder input and com-
munity involvement should
be considered.
Hyperlinked Administrative Record Information
em Reference Phrase in ROD Location in ROD
Site 12 is the crash-crew Section 2.1
training area
hydrogeologic setting Section 2.2
Identification of Referenced Document Available in
the Administrative Record1
Final Remedial Investigation Report, Operable Unit 6, Site 12,
Crash Crew Training Area, MCAS Cherry Point, North Carolina.
Attachment 2, Section 2.2, Pages 2-1 through 2-3. CH2M HILL,
December 2005.
Final Remedial Investigation Report, Operable Unit 6, Site 12,
Crash Crew Training Area, MCAS Cherry Point, North Carolina.
Section 4.3.4.1, Pages 4-10 through 4-13. CH2M HILL.
4.3.4.1 Site 12 Geology and Hydrogeology
The USGS has conducted several studies of the hydrogeology at MCAS Cherry Point. A
description of MCAS Cherry Point geology and hydrogcology as described by the.- USGS is
presented to provide an overview of available information and characteristics of the
hydrostratigraphic units at the MCAS.
While developing a quasi three-dimensional finite-difference ground water-flow model and
while analyzing the hydrogeologic framework of MCAS Cherry Point, the USGS evaluated
geophysical and litliologic well log data from 30 wells and water-level data from oil test
wells, water supply wells, and observation wells. The subsurface materials evaluated by the
USGS investigations and supported by site borings are separated into the following aquifers
and respective confining units: Surficial Aquifer, Yorktown Aquifer, Pungo River Aquifer,
upper Castle Hayne Aquifer, and lower Castle Haync Aquifer. Deeper aquifers are not
addressed in this site-specific discussion because the depth and separation of these aquifers
from contaminant sources by a series of confining units, as well as the brackish water
quality of the deeper aquifers, preclude the potential for significant impacts to these deeper
aquifers.
Other Optional Electronic Enhancements
The public information repository is located at the
library, Havelock, NC 28532, Phone 252-447-7509
remedy section process will be available the
IR Program website
ROD with
Optional
Reference CD
-------
United States Office of Solid Waste OSWER 9355.6-10
Environmental Protection and Emergency Response September 2011
Agency ° ' r r
------- |