&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

-------
                            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

-------
                       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



-------
                           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

-------
                           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

-------
                               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


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United States                         Office of Solid Waste                              OSWER 9355.6-10

Environmental Protection             and Emergency Response                             September 2011
Agency                                   °   '    r                                  r

-------