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Military Munitions Response Program
Record of Decision

Aberdeen Proving Ground - Aberdeen Area
Munitions Response Sites

April 2023

U.S. Army Garrison

Aberdeen Proving Ground, Maryland


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FINAL

Military Munitions Response Program
Record of Decision
Aberdeen Proving Ground - Aberdeen Area
Munitions Response Sites

U.S. Army Garrison
Aberdeen Proving Ground, Maryland

Contract W56ZTN-17-D-0011, Task Order W56ZTN20F0097

April 2022

Prepared for:

U.S. Army Environmental Command

2450 Connell Road
Fort Sam Houston, Texas 78234-7664

U.S. Army Garrison
Aberdeen Proving Ground
E5183 Blackhawk Rd
Gunpowder, Maryland 21010

Prepared by:

_3?SUNDANCE-EA II, LLC

Sundance-EA LLC
1311 Continental Drive, Suite K
Abingdon, Maryland 21009


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April 2023

Table of Contents

1.0 DECLARATION	1

1.1	Site Name and Location	1

1.2	Statement of Basis and Purpose	1

1.3	Assessment of Site	1

1.4	Description of Selected Remedy	2

1.5	Statutory Determinations	2

1.5.1	Part 1: Statutory Requirements	2

1.5.2	Part 2: Statutory Preference for Treatment	5

1.5.3	Part 3: Five-Year Review Requirement	5

1.6	Record of Decision Data Certification Checklist	5

1.7	Authorizing Signatures	6

2.0 DECISION SUMMARY	7

2.1	Site Name, Location, and Description	7

2.2	Site History and Enforcement Activities	8

2.3	Community Participation	9

2.4	Scope and Role of Munitions Response Site Response Action	10

2.5	Site Characteristics	10

2.5.1	Facility Profile	10

2.5.2	Physical Profile	13

2.5.3	Land Use Profile	15

2.5.4	Ecological Profile	15

2.5.5	Nature and Extent of MEC/MC Release Profile	16

2.6	Current and Potential Future Land Use and Resource Uses	19

2.6.1	Land Use	19

2.6.2	Groundwater and Surface Water Uses	20

2.7	Summary of Site Risks	20

2.7.1	MC Risk Assessment	20

2.7.2	MEC Concern Hazard Assessment	23

2.7.3	Basis for Taking Action	24

2.8	Remedial Action Objectives	24

2.9	Description of Alternatives	25

2.9.1	Alternative 1—No Action	25

2.9.2	Alternative 2—Land Use Controls for the MPR and FDA MRSs	25

2.10	Comparative Analysis of Alternatives	26

2.10.1	Threshold Criteria	28

2.10.2	Balancing Criteria	28

2.10.3	Modifying Criteria	30

2.11	Principal Threat Wastes	30

2.12	Selected Remedy	30

2.12.1	Summary of the Rationale for the Selected Remedy	31

2.12.2	Description of Selected Remedy	31

2.12.3	Annual Inspections	34

2.12.4	Comprehensive Environmental Response, Compensation, and Liability Act Five-
Year Reviews	34

2.12.5	Summary of Estimated Remedy Costs	35

2.12.6	Expected Outcomes of Selected Remedy	35

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2.12.7	Green Remediation	36

2.12.8	Remedial Design	36

2.13	Statutory Determinations	36

2.13.1	Protection of Human Health and the Environment	37

2.13.2	Compliance with Applicable or Relevant and Appropriate Requirements	37

2.13.3	Cost Effectiveness	37

2.13.4	Utilization of Permanent Solutions and Alternative Treatment Technologies to the
Maximum Extent Practicable	37

2.13.5	Preference forTreatment as a Principal Element	38

2.13.6	Five-Year Review Requirements	38

2.14	Documentation of Significant Changes	38

3.0 RESPONSIVENESS SUM MARY	39

3.1	Stakeholder Comments and Lead Agency Responses	39

3.2	Technical and Legal Issues	39

4.0 REFERENCES	40

1.	Version: 1.0	 1

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List of Figures

Figure 1. Site Location	3

Figure 2. Munitions Response Sites	4

Figure 3. MEC Conceptual Site Model	12

Figure 4. Munitions Response Sites LUC Boundaries	33

List of Tables

Table 1.	List of APG-AA MRSs Addressed in this ROD	1

Table 2.	Record of Decision Data Certification Checklist	5

Table3.	MMRP Activity Timeline	8

Table 4.	Public Notification of Document Availability	9

Table 5.	Public Comment Period Requirements	9

Table 6.	MPR and FDA MRS Remedial Action Alternatives	25

Table 7.	Evaluation Criteria for Superfund Remedial Alternatives	27

Table 8.	Comparative Analysis of Remediation Alternatives	28

Table 9.	Summary of ARARs for the MPR and FDA MRSs	29

Table 10.	Summary of Costs	30

List of Appendices

Appendix A MDE Letters of Concurrence (To be provided in Final Document)

Appendix B Affidavits for Public Notice
Appendix C Cost Summary

Appendix D Summary of Comments Received During Public Comment Period and Army
Responses

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Acronyms and Abbreviations

|jg/L	Micrograms per liter

%	Percent

§	Section

°F	Degrees Fahrenheit

AA	Aberdeen Area

AP	Armor-piercing

APG	Aberdeen Proving Ground

ARAR	Applicable or relevant and appropriate requirement

Army	U.S. Army

bgs	Below ground surface

BMP	Best management practice

BRAC	Base Realignment and Closure

CAIS	Chemical agent identification sets

CERCLA	Comprehensive Environmental Response, Compensation, and Liability Act

CFR	Code of Federal Regulations

COMAR	Code of Maryland Regulations

COPC	Contaminant of potential concern

COPEC	Contaminant of potential ecological concern

CRP	Community relations plan

CSM	Conceptual site model

DERP	Defense Environmental Restoration Program

DGM	Digital geophysical mapping

DoD	Department of Defense

EA	EA Engineering, Science, and Technology, Inc.

EOD	Explosive ordnance disposal

ERT	ERT, Inc.

EUL	Enhanced use lease

FDA	Former Demolition Area

FS	Feasibility study

ft	Feet or foot

GIS	Geographic information system

HA	Hazard assessment

HE	High explosive

HEI-T	High-explosive incendiary with tracer

HHRA	Human health risk assessment

HI	Hazard index

l&D	Identification and detonation

IRP	Installation Restoration Program

ID	Identification

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lb	Pound(s)

LUC	Land use control

LUCIP	Land use control implementation plan

MC	Munitions constituent

MDE	Maryland Department of the Environment

MDNR	Maryland Department of Natural Resources

MEC HA	MEC hazard assessment

MEC	Munitions and explosives of concern

mg/kg	Milligram per kilogram

MGFD	Munition with the greatest fragmentation distance

MK2	Mark II

mm	Millimeter(s)

MMRP	Military Munitions Response Program

MPR	Multi-Purpose Range

MRS	Munitions response site

MRSPP	Munitions Response Site Prioritization Protocol

NAWQC	National Ambient Water Quality Criteria

NCP	National Oil and Hazardous Substances Pollution Contingency Plan

O&M	Operation and maintenance

RAB	Restoration Advisory Board

RAO	Remedial action objective

RCRA	Resource Conservation and Recovery Act

Rl	Remedial Investigation

ROD	Record of Decision

RSL	Regional screening level

SI	Site inspection

SLERA	Screening-level ecological risk assessment

SSL	Soil screening levels

TBC	To be considered

TMV	Toxicity, mobility, and volume

TRV	Toxicity reference value

URS	URS Corporation

USEPA	U.S. Environmental Protection Agency

UU/UE	Unlimited use and unrestricted exposure

UXO	Unexploded ordnance

WBSA	Western Boundary Study Area

Aberdeen Area Munitions Response Sites
Aberdeen Proving Ground

Military Munitions Response Program
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1.0 DECLARATION

1.1 Site Name and Location

This Record of Decision (ROD) presents the selected remedial actions for three Aberdeen Proving
Ground (APG) - Aberdeen Area (AA) munitions response sites (MRSs) located on the
northwestern shore of the Chesapeake Bay in southern Harford County and southeastern
Baltimore County, Maryland. APG is 3 miles southeast of the City of Aberdeen and approximately
30 miles north of Baltimore (Figure 1). The AA MRSs are listed as Operable Unit 13 under the
Michaelsville Landfill National Priorities List Site that includes the APG-AA.

1.2 Statement of Basis and Purpose

This ROD presents the selected remedies for the three APG-AA MRSs identified in Table 1.

Table 1. List of APG-AA MRSs Addressed

in this ROD

MRS

HQAES
Site ID

AEDB-R
Site ID

Selected Remedy

Multi-Purpose Range (MPR)

24015.1303

APG-001-R-05

Alternative 2
(Land Use Controls [LUCs])

Former Demolition Area (FDA)

24015.1279

APG-001-R-02

Alternative 2
(LUCs)

Gas Identification and
Detonation (l&D) Area

24015.1302

APG-001-R-04

No Action

NOTES: AEDB-R = Army Environmental Data Base.

HQAES = Head Quarters Army Environmental Systems.
ID = Identification Number.

The locations of the three MRSs are shown on Figure 2. The selected remedies were chosen in
accordance with the Comprehensive Environmental Response, Compensation, and Liability Act
(CERCLA) of 1980, as amended, and to the extent practicable with the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP). This decision is based on the
Administrative Record file for the APG-AA.

This document is issued by the United States Army (Army), the lead agency conducting
environmental response activities under the Military Munitions Response Program (MMRP), and
the United States Environmental Protection Agency (USEPA), the lead regulatory agency. These
actions are being conducted in consultation with the State of Maryland, represented by the
Maryland Department of the Environment (MDE), the supporting agency. The MDE concurs with
the selected remedies (Appendix A).

1.3 Assessment of Site

Based on current conditions at APG-AA, the Army has determined that no unacceptable risks or
threats to public health or the environment exist at the Gas l&D Area MRS, which allows for
unlimited use and unrestricted exposure (UU/UE). Therefore, no action will be necessary under
CERCLA, as amended, to protect public health or welfare and the environment.

The remedial actions selected in this ROD for the MPR and FDA MRSs are necessary to protect
public health or welfare or the environment from actual or threatened releases of munitions and
explosives of concern (MEC) that may present an imminent and substantial endangerment to
public health or welfare.

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Aberdeen Proving Ground

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1.4	Description of Selected Remedy

As noted in Table 1, the selected remedies for the three APG-AA MRSs are:

•	MPR MRS: Alternative 2: LUCs

•	FDA MRS: Alternative 2: LUCs

•	Gas l&D Area MRS: No Action.

The MPR and FDA MRSs will remain at their current status, which consists of MEC potentially
present at 2 feet below ground surface or greater. No remediation will be performed at the MRSs.
Because subsurface MEC may remain, LUCs will be implemented that focus on reducing human
exposure to MEC by managing the activities occurring at the MRSs. The LUCs include a Safety
Excavation Permit Program with unexploded ordnance (UXO) construction support, training and
awareness programs, and annual inspections. Because hazards may remain in the MPR and
FDA MRSs that do not allow for UU/UE, CERCLA Five-Year Reviews will be conducted to assess
the implementation and performance of the remedy to determine whether the remedy continues
to remain protective of human health and the environment. In addition, an MRS Prioritization
Protocol (MRSPP) Annual Update will be prepared, in accordance with the requirements of
32 Code of Federal Regulations (CFR) Part 179. The MRSPP is the methodology used by the
Department of Defense (DoD) for prioritizing sites known or suspected to contain UXO, discarded
military munitions, or munitions constituents (MC) for response actions. The MRS priority ranking
is reviewed at least annually, and updated as necessary, to reflect new information. Additional
detail on the LUC remedy is provided in Sections 2.9 and 2.12.

The Gas l&D Area received a no action recommendation at the conclusion of the remedial
investigation (Rl), and this recommendation was maintained through the feasibility study (FS) and
Proposed Plan. No action was recommended because the Rl found no evidence of a release,
and no unacceptable risks to human health and the environment related to MMRP hazards were
present. Therefore, no CERCLA action (i.e., No Action) is necessary to protect human health
and/or the environment at the Gas l&D Area MRS.

1.5	Statutory Determinations

This section confirms that the selected remedies attain the mandates of CERCLA § 121 and, to
the extent practicable, the NCP. Part 1 affirms that the selected remedies satisfy CERCLA § 121
requirements. Part 2 indicates whether the remedies satisfy the statutory preference for treatment
as a principal element. Part 3 indicates whether a 5-year review is applicable.

No MEC hazards, hazardous substances, pollutants, or contaminants (i.e., MC) were found at the
Gas l&D MRS. Therefore, the Army has concluded that no remedial action is necessary to ensure
protection of human health and the environment, and a 5-year review requirement is not
warranted for the Gas l&D MRS.

1.5.1 Part 1: Statutory Requirements

The selected remedy for the MPR and FDA MRSs (LUCs) is protective of human health and the
environment, complies with applicable or relevant and appropriate requirements (ARARs), is cost
effective, and uses permanent solutions and alternative treatment technologies to the maximum
extent practicable.

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Military Munitions Response Program
Record of Decision


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Aberdeen Area Munitions Response Sites
Aberdeen Proving Ground

Military Munitions Response Program
Record of Decision

Cecil County

North-East

Harford
County

Aberdeen-Havre
de Grace-Bel Air

City of
Aberdeen

Multi-Purpose
Range

Gas Identification
and Detonation Area

Former
Demolition
Area

Spesutie
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Lauderick Creek.

APG Aberdeen Area

Pooles
Island

Kent County

APG Edgewood Area

Chester! owfr

Anne
Arundel
County

Prince
George's
County

Figure 1
Site Location

Aberdeen Proving Ground

Maryland

Map Projectbn: NAD 1983 StatePlane Maryland FIPS 1900 Feet
Base map: ESRI World Street Map WMS

I Kilometers

I I MRS Location
I I APG Aberdeen Area
APG Edgewood Area

Caroline
County

Howard County

ury county

Baltimore

^§ff£

Queen
Anne's
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Chesapeake Bay

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Canal Creek ¦


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Figure 2 - Munitions Response Sites, Aberdeen Area, Aberdeen Proving Ground, MD

	^

Multi-Purpose Range
(APG-001 -R-05)

Gas Identification and
Detonation Area
(APG-001-R-04)

Former Demolition Area
(APG-001 -R-02)

Phillips, AAE
' Airport

Legend

Monitoring Well
A Survey Monument
Road

	 Phillips AAF

= Stream
|_^"j Historic Demo Pit
I MRS Areas
- - New Buildings
t-J (2011)

Soil Pile (2011)
Pond

Golf Fairways
Building
Wooded Areas

Area Shown
in Main Map

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1.5.2 Part 2: Statutory Preference for Treatment

No treatment will be performed. Therefore, the selected remedy for the MPR and FDA MRSs
does not satisfy the statutory preference for treatment by reducing the MEC hazard and volume
through detection, removal, and permanent destruction of MEC. However, in the unlikely event
that MEC are identified during construction support activities conducted under the selected
remedy, a minor reduction in toxicity, mobility, and volume through treatment (i.e., detonation)
could occur.

1.5.3 Part 3: Five-Year Review Requirement

Because hazards may remain in the MPR and FDA MRSs that do not allow for UU/UE, CERCLA
Five-Year Reviews will be conducted to assess the implementation and performance of the
remedy to determine whether the remedy continues to remain protective of human health and the
environment. Therefore, in accordance with NCP § 300.430(f)(4)(H), a statutory review will be
conducted within 5 years after initiation of remedial action, and every 5 years thereafter as long
as the potential for hazards remains.

1.6 Record of Decision Data Certification Checklist

This section provides a data certification checklist (Table 2), which certifies that this ROD contains
key remedy selection information. Table 2 includes references to section numbers where the
information can be found in the Decision Summary section of this ROD (Section 2.0). Additional
information can be found in the APG Administrative Record file maintained at the following
locations:

Harford County Public Library
Edgewood Branch

629 Edgewood Road

Edgewood, Maryland 21040

Phone: 410-612-1600

Hours: Mon and Wed: 10 a.m.-8 p.m.

Tue and Thu: 1 p.m.-8 p.m.

Fri and Sat: 10 a.m.-5 p.m.

Sun: Closed

Harford County Public Library
Aberdeen Branch

21 Franklin Street

Aberdeen, Maryland 21001

Phone: 410-273-5610

Hours: Mon and Wed: 10 a.m.-8 p.m.

Tue and Thu: 1 p.m.-8 p.m.

Fri and Sat: 10 a.m.-5 p.m.

Sun: 1 p.m.-5 p.m.

Washington College

Clifton M. Miller Library Kent County
Chestertown, Maryland 21620
Phone: 410-778-7279
Hours: M-F: 8 a.m.-4:30 p.m.

APG Administrative Record

Building E6882

Aberdeen Proving Ground, Maryland 21010
Phone: 410-436-7313
By appointment only.

Table 2.

Record of Decision Data Certification Checklist

Data

ROD Section

MEC and their distribution

Section 2.5.5

Baseline risks represented by MEC

Section 2.7

Cleanup levels for contaminants of concern (COCs) and the basis for these
levels

Not Applicable

How source materials constituting principal threats are addressed

Section 2.11

Current and reasonably anticipated future land use assumptions

Section 2.6

Potential land and groundwater use that will be available because of the
selected remedy

Section 2.6 and
2.12.6

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Table 2. Record of Decision Data Certification

Record of Decision Data Certification Checklist

Data

ROD Section

Estimated capital costs, annua) operation and maintenance (O&M) costs, total
present worth costs, discount rate, and the number of years over which the
remedy cost estimates are projected	

Section 2.12.5

Key factor(s) that led to selecting the remedy

Section 2.13

1.7 Authorizing Signatures

This ROD presents the selected remedy for three APG-AA MRSs:

•	MPR MRS: Alternative 2: LUCs

•	FDA MRS: Alternative 2: LUCs

•	Gas l&D Area MRS: No Action.

The Army is the lead agency under the Defense Environmental Restoration Program and has
developed this ROD consistent with CERCLA, as amended, and to the extent practicable with the
NGP. Together, the Army and USEPA, the lead regulatory agency, selected the final remedial
actions for the MRSs. This ROD will be incorporated into the Administrative Record file for APG,
which is available for public review at the locations described in Section 1.6. The undersigned
Army and USEPA representatives approve this document, which presents the selected remedy.

Date

| CAM ARP) Digitally signed by PAUL LEONARD
LtUIMnnU Date: 2023.07.26 11:35:52 -04'00'

Paul Leonard
Director

Superfund and Emergency Management Division
U.S. Environmental Protection Agency, Region 3

Date

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Aberdeen Proving Ground

Military Munitions Response Program
Record of Decision


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2.0 DECISION SUMMARY

This decision summary provides an overview of the characteristics of the munitions response
sites (MRSs), the alternatives evaluated, and the analysis of those alternatives. It also identifies
the selected remedies, explains how the remedies fulfill statutory and regulatory requirements,
and provides a substantive summary of the Administrative Record file that supports the remedy
selection decision. Although some of the information in this decision summary is similar to the
information in the Declaration (Section 1.0), this section discusses the topics in greater detail and
provides the rationale for those "summary declarations."

While this document provides a consolidated summary of information about the MRSs and the
selected remedies, it is only one part of the Administrative Record file, which contains the full
details of the MRSs' characterization, the alternatives evaluation, and remedy selection.

This Record of Decision (ROD) has been prepared in accordance with United States
Environmental Protection Agency (USEPA) ROD guidance (USEPA 1999, 2011). The ROD is
based on the Aberdeen Proving Ground (APG) Aberdeen Area (AA) remedial investigation (Rl)
(ERT, Inc. [ERT] 2014), the feasibility study (FS) (Bay West LLC 2017), and the Proposed Plan
for the APG-AA MRSs (United States Army [Army] 2022).

2.1 Site Name, Location, and Description

The APG installation is located on the northwestern shore of the Chesapeake Bay in southern
Harford County and southeastern Baltimore County, Maryland. APG is 3 miles southeast of the
City of Aberdeen and approximately 30 miles north of Baltimore (Figure 1). The APG installation
encompasses approximately 72,500 acres, which include large bodies of water and marshy,
wooded terrain. The Bush River divides the land portion of APG into two separate areas. The
area north of the Bush River is referred to as the APG-AA, and the area south of the Bush River
is referred to as the APG-Edgewood Area. The APG-AA consists of 27,533 acres of land, and the
APG-Edgewood Area consists of 9,734 acres of land. The MRSs addressed in this ROD are in
the APG-AA. The MRSs located in APG-Edgewood Area are addressed in a separate ROD.

APG is a secure Department of Defense (DoD) facility, and general access is restricted along the
property boundary by barriers (i.e., fences), "No Trespassing" signs, and guards. Multiple layers
of security exist in some areas and "No Trespassing" signs and random patrols are used in areas
where access could be reached by water. However, two of the APG-AA MRSs (the Multi-Purpose
Range [MPR] and Former Demolition Area [FDA] MRSs, which together form the Ruggles Golf
Course) are outside the restricted-access area. Specific land use controls (LUCs) in place at APG
are documented in RODs and are included in APG's Land Use Control Implementation Plan
(LUCIP), which is updated periodically. This plan provides an extensive list of practices that are
applicable to the entire installation and LUCs implemented by the installation where land could be
unsafe for unlimited use and unrestricted exposure (UU/UE). Two examples of these practices
are that workers and residents are all trained in the 3Rs (Recognize, Retreat, Report [munitions])
and have been told that digging is prohibited without prior clearance through the safety excavation
permit program. This prevents unintentional contact with munitions and explosives of concern
(MEC). The process has been demonstrated to be effective as no incidents have occurred since
the program was adopted.

The FDA and MPR MRSs are south of Route 715; the FDA MRS is the southeastern corner of
Ruggles Golf Course and the MPR MRS is the western portion of the golf course (Figure 2). Fill
material was placed over the majority of the MRSs when the golf course was initially constructed

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in the 1950s. Future land use at the MRSs is expected to remain consistent with current land use,
i.e., an active golf course. As noted previously, APG is a secure facility and access is restricted
to Army personnel, authorized civilian personnel, contractors, and visitors to specific destinations.
However, once on the installation, no barrier is in place surrounding the FDA and MPR MRSs.

2.2 Site History and Enforcement Activities

The Defense Environmental Restoration Program (DERP) was formally established by Congress
in 1986 and provides for the cleanup of DoD sites under the jurisdiction of the Secretary of
Defense. The Army has two restoration programs under DERP at active/operating Army
installations: The Installation Restoration Program (IRP) and the Military Munitions Response
Program (MMRP). The IRP is a comprehensive program to identify, investigate and clean up
hazardous substances, pollutants, and contaminants at active/operating Army installations. The
MMRP addresses non-operational range lands that are suspected or known to contain MEC and
munitions constituents (MC) located on current and former military installations. The DERP,
including the MMRP, follows the Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA) and the National Oil and Hazardous Substances Pollution Contingency
Plan (NCP). Management of MEC under DERP-MMRP is being conducted by the Army, the lead
agency, in accordance with CERCLA, as amended, and to the extent practicable with the NCP.
This action is conducted by the Army with the concurrence of USEPA, the lead regulatory agency.
The FDA and MPR MRSs are associated with the APG Michaelsville Landfill National Priorities
List Site (MD3210021355), which was placed on the National Priorities List in October 1989.

A series of assessments, site inspections (Sis), RIs, an FS, and other data collection activities
under CERCLA and DERP have occurred at the APG-AA MRSs addressed in this ROD since
2006. A summary of the investigations and actions performed at APG-AA addressing potential
MEC and MC are summarized in Table 3. A description and history of the three MRSs are
presented in Section 2.5.

Table 3.	MMRP Activity Timeline

Date

Activity

2006

Historical Records Review—Potential MRSs identified at APG-AA through interviews
and archive research. The three MRSs in this ROD were not identified through the
Historical Records Review.

2007

SI—Environmental sampling and field surveys were performed. The three MRSs in
this ROD were not investigated during the SI.

2008

Contractor finds MEC and munitions debris near Ruggles Golf Course.

2008

Preliminary Assessment for FDA—Research into the historical activities that led to
the MEC being present near the Golf Course was performed. As part of the
Preliminary Assessment for the FDA, an additional search and review of historical
records detailing potential use of the site was conducted and three additional MRSs
were identified: Combat Course, Gas Identification and Detonation (l&D) Area, and
MPR.

2010

SI Addendum—No fieldwork performed. Report updated the previous SI Report to
include the three MRSs included in this ROD.

2011

Western Boundary Area Rl—Groundwater in Operable Unit 2, which includes the
three MRSs in this ROD, was investigated. Groundwater sampling confirmed that no
impacts to groundwater from activities at the MRSs had occurred.

2014

APG-AA Rl—Included digital geophysical mapping (DGM), environmental sampling
for MC, intrusive MEC investigations, and human health and ecological risk
evaluations.

2017

FS to evaluate remedial alternatives for the MPR and FDA MRSs.

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Table 3.	MMRP Activity Timeline

Date

Activity

2022

Proposed Plan to present the preferred alternatives for the MPR, FDA, and Gas l&D
Area MRSs.

2.3 Community Participation

The NCP § 300.430(f)(3) establishes several public participation activities that the lead agency
must conduct during the remedy selection process. Components of these activities and
documentation of how each component was satisfied for the MRSs are described in Table 4 and
Table 5.

Table 4. Public Notifical

tion of Document Availability

Requirement

Satisfied By

Notice of the availability of the Proposed Plan
must be made in a general-circulation major local
newspaper.

Notice of availability was published on 18 March
2022 in The Aegis, The Cecil Whig, and the Kent
County News, and is included for reference in
Appendix B.

Notice of the availability must include a brief
abstract of the Proposed Plan, which describes
the alternatives evaluated and identifies the
preferred alternative [NCP § 300.430(f)(3)(i)(A)].

The notice of availability included the required
components and is included for reference in
Appendix B.

Table 5. Public Comment Period Requirements

Requirement

Satisfied By

The lead agency should make the document
available to the public for review on the same date
as the newspaper notification.

The Proposed Plan was made available to the
public on 18 March 2022.

The lead agency must ensure that all information
that forms the basis for selecting the response
action is included as part of the Administrative
Record file and is made available to the public
during the public comment period.

The APG Directorate of Public Works—
Environmental Division maintains the
Administrative Record file for the MRSs and
included a copy of relevant documents in an
Information Repository at the Harford County
Library (Edgewood and Aberdeen Branches).
Data collected and CERCLA primary documents
produced for the MRSs were placed therein and
made available to the public at those locations.

CERCLA § 117(a)(2) requires the lead agency to
provide the public with a reasonable opportunity to
submit written and oral comments on the
Proposed Plan.

NCP § 300.430(f)(3)(i)(C) requires the lead
agency to allow the public a minimum of 30 days
to comment on the Proposed Plan and other
supporting information located in the
Administrative Record.

The Army provided a public comment period for
the Proposed Plan and other supporting
information from 21 March 2022 to 20 April 2022.

The lead agency must extend the public comment
period by at least 30 additional days upon timely
request.

The Army received no requests to extend the
public comment period.

The lead agency must provide the opportunity for
a public meeting to be held at or near the MRS
during the public comment period.

A virtual public meeting was held on 31 March
2022.

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2.4	Scope and Role of Munitions Response Site Response Action

There are two APG areas under investigation, the APG-AA and APG-Edgewood Area. Each of
these areas have multiple IRP sites and MMRP sites that are in various stages of investigation
and remediation. This ROD addresses three of the four MMRP sites within APG-AA (MPR MRS,
FDA MRS, and Gas l&D Area MRS). The fourth site (Enhanced Use Lease [EUL] Site MRS) is
being addressed in a separate ROD.

Activities at the MRSs have been and are currently being performed in accordance with the
CERCLA remedial process and are consistent with the NCP. The remedial actions selected in
this ROD are the final remedies for the MRSs addressed.

2.5	Site Characteristics

This section provides an overview of the site, including a description of the conceptual site model
(CSM) on which the risk assessment and response actions are based. The CSM is a description
of a site and its environment that is based on existing knowledge. The CSM describes the sources
of MEC and MC hazards at a site, actual or potential pathways of exposure, current or proposed
use of property, and potential receptors to MC or explosives hazards. The CSM provides a
planning tool to integrate site information from a variety of sources, evaluate the information with
respect to project objectives and data needs, and respond through an iterative process for further
data collection or response action. Development of the CSM is a process that reflects the progress
of activities at the MRSs from initial assessment through site closeout. Information used to create
the CSM includes the following:

•	Facility Profile: Describes history, location, and man-made features at or near the site

•	Physical Profile: Describes factors that may affect release, fate, and transport

•	Land Use and Exposure Profile: Provides information used to identify and evaluate the
applicable exposure scenarios and receptor locations

•	Ecological Profile: Describes the physical relationship between developed and
undeveloped portions of the site, use of the undeveloped portions, and ecological use

•	Nature and Extent of MEC/Release Profile: Presents the extent of contaminants or
hazards in the environment.

These profiles are described in detail in the following subsections (land use is described in
Section 2.6). A visual depiction of the current site MEC CSM is presented in Figure 3.

2.5.1 Facility Profile

MPR MRS: The 179.8-acre MPR MRS is adjacent to the FDA MRS and lies south of Route 715
and east of the installation boundary in the APG-AA. The western portion of Ruggles Golf Course
currently overlies the former location of the MPR MRS. Aerial photographs indicate that the MPR
MRS was constructed between 1945 and 1947 and use of the range ended between 1952 and
1956. Historical data indicate the site was used for training with mines and booby traps, rifle
grenades, hand grenades, and rocket launchers (ERT 2014). The MPR MRS was initially
identified as an MRS in 2008 during review of a 1951 Ordnance Replacement Training Center

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map completed as part of the preliminary assessment (APG 2008). Fill material was placed over
the majority of the MPR MRS when the golf course was initially constructed in the 1950s.

FDA MRS: The 59.4-acre FDA MRS is located south of Route 715 on the eastern portion of
Ruggles Golf Course. The FDA MRS was used by the Ordnance Replacement Training Center
from 1942 through 1947 (URS Corporation [URS] 2007). Historical documentation indicated that
there was also a 23-acre Bomb Recovery Area within the FDA that was used by the Ordnance
Center and School in the mid-1950s for recovering inert bombs dropped from aircraft. During this
training, an inert bomb was dropped by aircraft and would penetrate the ground surface. Trainees
would be required to locate the point of entry, access the bomb, and then render safe and recover
the bomb (EA Engineering, Science, and Technology, Inc. [EA] 2011). Munitions discovered at
the MRS include high explosive (HE) loaded projectiles, grenades, fuzes, bombs, boosters, and
rockets. These included munitions of both American and foreign origins. The FDA was initially
identified as an MRS in January 2008 when civilian unexploded ordnance (UXO) contractors
encountered 57 MEC/munitions debris items at 5-6 feet (ft) below ground surface (bgs) during
excavation of an irrigation pond on Ruggles Golf Course (ERT 2014). The irrigation pond is within
the boundaries of the historical demolition pit. These items were recovered and properly disposed
of and/or detonated in place by Explosive Ordnance Disposal (EOD) personnel, and the remaining
metal was recycled offsite. The items included the following: two point-detonating fuzes, one
booster, one HE hand grenade, one 20-millimeter (mm) armor-piercing (AP) projectile, one
20-mm HE projectile, one German 20-mm HE projectile, three German 37-mm AP HE projectiles,
two 40-mm Mark II (MK2) HE incendiary with tracer (HEI-T) projectiles, 26 40-mm projectiles (not
intact), one 57-mm HE projectile, one 57-mm M306 projectile, nine 75-mm HE projectiles, two
experimental 75-mm AP projectiles, one 76-mm HE projectile, three 90-mm projectiles, one
105-mm M1 HE projectile, and one 3.5-inch rocket warhead. The 3.5-inch rocket warhead was
confirmed to be MEC.

Per an APG summary report to Maryland Department of the Environment (MDE), buried ordnance
was also discovered near the demolition pit within the FDA MRS during April 2010 construction
excavation activities at the golf course. These munitions were subsequently recovered and
properly disposed of and/or detonated in place by EOD personnel. The items included: one
500-pound (lb) bomb (unfuzed); one 155-mm projectile with armed fuze; six 37-mm projectiles;
three fuzes; and two 100-lb bombs. Because of these discoveries, APG EOD personnel
conducted mandatory pre-construction UXO sweeps of all planned excavation areas during golf
course construction upgrades.

Fill material was placed over most of the FDA MRS when the golf course was initially constructed
in the 1950s. The fill material was observed during construction of the irrigation pond within the
FDA MRS in 2008.

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Figures. MEC Conceptual Site Model

Source

Interaction

Primary
Source

Acess

Location Release Mechanism

Exposure
Routes

Receptors

CURRENT/FUTURE

Authorized
Installation
Personnel

Authorized
Contractors

Trespassers

Ecological
Receptors

MEC

MEC at the Surface
	?	

Handle/Tread Underfoot

Access
Available

Frost

Heave/Flood/Erosion
	?	

No Access



MEC near surface the Subsurface



Intrusive activity













0.1 -2ft































MEC in the Subsurface



Intrusive activity





©



©



>2ft







The MRSs have been covered with fill material and investigation data indicate that the exposure pathway for
interaction between humans and MEC on the surface and near surface (less than 2 ft bgs) is incomplete.

Complete Pathway
© Potentially Complete
Incomplete Pathway

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Gas l&D Area MRS: The 4.4-acre Gas l&D Area MRS is approximately one-half mile east of the
other two MRSs, just south of Route 715. The Gas l&D MRS was identified on a 1951 map that
detailed training areas used by the Ordnance Replacement Training Center. A gas training
chamber was also identified, but it is not eligible for the MMRP because it is in a closed structure.
The MRS included a 100-yard by 170-yard area that was used to train soldiers to be proficient in
the identification of gases through odor and other sensory reactions. Although the specific period
of operation of the range is unknown, operations could have been conducted from the World
War II period through at least the Korean War.

During the time frame in which the area may have been used for training (approximately the 1940s
through the mid-1950s), the following Chemical Agent Identification Sets (CAIS) may have been
used at APG: M1 (K951 and K952) and AN-M1A1 (K953 and K954). CAIS kits are not considered
MEC items; therefore, there is no potential for explosive hazards at the MRS. The CAIS consisted
of agents and industrial chemicals in sealed Pyrex® containers. Typical procedures started by
burying canisters in shallow holes, approximately 10-20 yards apart. Detonators were fastened
to each tube with adhesive plaster. Tubes were laid in the holes with detonators underneath so
that the explosion would throw the liquid into the air and produce a cloud of vapor. The M1 CAIS
and the AN-M1A1 CAIS contained various chemical agents in small dilute quantities, including
chloropicrin, phosgene, sulfur or nitrogen mustard, lewisite, cyanogen chloride, and tabun. Safety
procedures in place directed that the detonators be kept separate from the CAIS and not be left
at the site, so it is unlikely that any detonators would be present.

During the Rl, the majority of the Gas l&D MRS was being used to stockpile soil associated with
Base Realignment and Closure (BRAC) construction efforts at APG (ERT 2014). Therefore, the
depth of subsurface soil samples was adjusted to collect samples beneath the stockpile soil to
evaluate the nature and extent of potential historical impacts to human health and the
environment.

2.5.2 Physical Profile
2.5.2.1 Meteorology

APG experiences a modified temperate climate. The atmospheric effects caused by the
installation's proximity to the Chesapeake Bay, the Atlantic Ocean, and Appalachian Mountains
prevent APG from having a typical mid-latitude temperate climate. Wnters are humid and
generally milder than in the inland areas, and summers are hot and humid with frequent
thunderstorms.

The average annual air temperature is approximately 55 degrees Fahrenheit (°F). Average daily
temperatures generally range from 33°F in the winter to 75°F in the summer. Temperatures
commonly exceed 90°F during the summer and are accompanied by high humidity, yielding a
subtropical climate. The average relative humidity is 74 percent (%). The warmest period of the
year is during July and August, and the coldest period of the year is during January and February.
Average annual precipitation is approximately 42 inches. The distribution of monthly precipitation
is uniform throughout the year; the maximum precipitation usually occurs in late spring, or mid- to
late summer, and the minimum precipitation usually occurs in late summer or fall (National
Oceanic and Atmospheric Administration 2012). The depth of the frost line for the area is 64
inches, per Unified Facilities Criteria 3-310-01, dated 25 May 2005. This depth is considered to
be the depth at which a significant number of frost cycles are expected, there is frost susceptibility,
and moisture is available. All three of these parameters are required to produce frost-related
migration of MEC.

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Prevailing winds are from the west to northwest in the fall and winter and from the south to
southwest in the spring and summer. Average annual wind velocity ranges from 6 to 10 miles per
hour but can reach over 50 miles per hour and higher during severe storms (URS 2007).

2.5.2.2	Surface Features

APG is located within the Atlantic Coastal Plain, which is characterized by low-lying wetlands,
gently rising knolls and hills, with little change in elevation. These features were created as
material eroded from the hills to the west and was deposited eastward. APG topography and
surface features are characterized by low hills, shallow valleys, flat plains and extensive marshes.
Elevations range from 0 to 70 ft above sea level. Small creeks drain the land surface and
discharge into the Chesapeake Bay or tributaries of the bay. The shoreline is typical of the bay's
western shore (low, marshy shorelines to steep bluffs 15-20 ft in height).

2.5.2.3	Soil

The soil at APG is moderately to well drained, and is underlain by sandy, loamy, gravelly, or
clayey sediments on smooth uplands. Soil of the floodplains and low terraces is generally
moderately well drained to well drained and is underlain by stratified alluvial sediments. The
dominant soil types present are the Sassafras, Elkton, and Keyport series. All three series
developed from the deposition of marine sediment. Along most non-tidal wetland areas, the
Meadow series/Alluvial land series is dominant. In tidally influenced wetlands, the Tidal Marsh
series is dominant. Surface soil and sediment near marshes, low-lying floodplain areas, and the
shorelines contain abundant organics. Many of these soils include peat, organic-silt, and organic
clay with varying sand content. At the FDA and MPR MRSs, as at most areas of APG, fill from
other locations has been added as improvements or soil has been reworked over the past
50 years.

2.5.2.4	Surface Water

All surface water systems within APG are linked to the Chesapeake Bay, its tributaries, and
associated wetlands. The APG-AA lies within the Gunpowder-Middle-Back-Patapsco-Magothy-
Severn-South-Rhode-West drainage system. Over 39,000 acres of APG consist of the waters of
the Chesapeake Bay and its tributaries. The developed eastern section of APG-AA is drained
primarily by the upper portions of Romney Creek, and by Swan, Woodrest, and Dipper Creeks,
which flow into Spesutie Narrows. Undeveloped portions of APG-AA are drained by the lower
branches of Romney, Mosquito, and Delph creeks, and the Bush River.

The Susquehanna River joins the Chesapeake Bay approximately 4 miles north of Spesutie
Island. In this region of the Upper Bay, the Susquehanna accounts for 97% of the incoming
freshwater and most of the fluvial sediments that enter the Chesapeake Bay. Due to the massive
influx of freshwater from the Susquehanna watershed, seasonal and annual fluctuations in
salinity, turbidity, and water chemical quality are common. The location of APG in this portion of
the bay, where a delicate mixture of salt and fresh water occurs, makes the installation's waters
an important environment for the reproduction and rearing of many estuarine and marine
organisms (ERT 2014).

Modified wetlands and drainages are common throughout the installation. Small ponds created
by military activities and wildlife are regular features in the landscape of the unmanaged portions
of APG. Man-made drainage channels that vary from 0.5 to 7.0 ft in width and from 1.0 to 6.0 ft
in depth are frequent in low-lying portions of the installation. These drainage structures are

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associated with underground pipe systems and open ditches that are constructed from a variety
of materials (ERT 2014).

Decorative man-made drainage ponds are present at the golf course. In the MPR MRS, near the
approximate geographic center of the golf course, a small pond is present. This pond and a larger
pond, north of Route 715, discharge south via a drainage ditch or intermittent stream. In the FDA
MRS, another small man-made irrigation pond is present in the eastern portion of the MRS, within
the historical demolition pit area. Although these three water bodies may be used by wildlife such
as amphibians, fish, and birds, an initial site walkover and observations made during the Rl
fieldwork indicated low ecological use of the ponds (ERT 2014). The MPR and FDA surface water
features are not used for drinking water or fishing.

2.5.2.5 Hydrogeology

Shallow (10-37 ft bgs) groundwater is present at the APG-AA MRSs. A groundwater divide exists
in the shallow groundwater aquifer, such that groundwater north of the golf course discharges to
Swan Creek. However, from the MPR and FDA MRSs, the shallow groundwater flows west-
southwest. The shallow groundwater at the Gas l&D MRS flows north-northeast. Groundwater at
the Gas l&D MRS was not sampled during the investigation because there was no historical MEC
usage at this MRS.

Although a clay layer separates the upper and lower aquifers (30-80 ft bgs) beneath the MPR
MRS and FDA MRS, it may only be a semi-confining layer as it appears that the aquifers become
interconnected west and south-west of the MRSs.

Historical water table measurements were used to contour and compare to the estimated
elevations of the surface water bodies on the golf course (a south-flowing intermittent stream in
the center of the MPR MRS, a small pond just west of the stream in the center of the MPR MRS
[central pond], and an irrigation pond in the FDA MRS demolition pit area) to determine if
groundwater could mix with surface water. Under most conditions, groundwater is unlikely to be
affecting the surface water. For the irrigation pond in the FDA MRS, the bottom of the pond is
estimated to be 20 ft above the water table, indicating that there is no hydraulic connection
between surface water and groundwater. For the stream bed and the central pond, however, the
water table is only a few feet below the bottom of the stream bed and central pond. Although the
likelihood is small, it is possible that a hydraulic connection may occur during extreme storm
events.

2.5.3	Land Use Profile
2.5.3.1 Demography

The population of Harford and Baltimore Counties as reported in the 2021 U.S. Census was
1,112,293. The MRS is located approximately 3 miles southeast of the City of Aberdeen, which
had a population of 16,889 in 2021. Current and potential future land and water use is described
in Section 2.6.

2.5.4	Ecological Profile

The MPR and FDA MRSs are a part of a developed golf course where fill has been added over
many years. Although the area is accessible to wildlife, the conditions are not ideal for these
receptors, as the area is regularly mowed and visited by golfers. The highly developed conditions
at the MRSs may represent a low-value habitat for birds and terrestrial mammals, as the degree

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of disturbance is high. Many acres of secondary forest growth and wetlands exist elsewhere on
the installation, mainly located on the active range areas.

The physical boundaries of the Western Boundary Study Area (WBSA) Rl included the Ruggles
Golf Course and former Gas l&D area. The ecological setting of the WBSA consists of a mixture
of mowed/unmowed open fields, developed areas, marsh areas, and forests; the Ruggles Golf
Course area consists primarily of a large, mowed, grassy area surrounded by narrow stands of
trees, and containing a few buildings, small ponds, and a stream/drainage ditch that contains
running water only after storm events (EA 2011).

Common terrestrial wildlife species that would be expected to use the MRSs include white-tailed
deer (Odocoileus virginianus), gray squirrel (Sciurus carolinensis), eastern chipmunk (Tamias
striatus), red fox (Vulpes vulpes), groundhog (Marmota monax), and opossum (Didelphis
virginiana). Species that exist in marshes in the area and that might be locally present in the man-
made lakes on Ruggles Golf Course include muskrat (Ondatra zibethicus), herons, egrets, rails,
and various turtles and amphibians.

The WBSA Rl report (EA 2011) lists vegetation in the marshes of the WBSA, and it is assumed
that similar vegetation can be found in the ponds and intermittent streams of the golf course.
Common plant species associated with the WBSA waters include grasses, sedges, cattail (Typha
spp.), arrow-arum (Peltandra virginica), pickerel weed (Pontenderia cordata), common
winterberry (Ilex verticillata), marsh mallow (Kosteletzkya virginica), and common reed
(.Phragmites australis). Although no specific data were found regarding the aquatic invertebrates
of the freshwater ponds and streams of APG, freshwater invertebrates in Maryland streams are
outlined in a document by the Maryland Department of Natural Resources (MDNR 2002). It is
assumed that, in general, typical species of freshwater invertebrates exist in the golf course ponds
and intermittent streams, and may include mussels and clams (Bivalvia), snails and limpets
(Gastropoda), insect and non-insect Arthropoda, Collembola, and aquatic worms.

2.5.5 Nature and Extent of MEC/MC Release Profile

The nature and extent of contamination includes the sources and types of MEC and MC, their
inferred mechanisms for release, and any potential influences from natural features or events that
could affect distribution. The profile builds upon the historical, physical, and ecological information
presented in the preceding sections.

In the various environmental investigations that have been completed for the APG-AA MRSs, soil
analytical results were compared to APG and regional background levels, USEPA residential soil
Regional Screening Levels (RSLs), MDE Residential Soil Cleanup Standards, USEPA Protection
of Groundwater Soil Screening Levels (SSLs), and USEPA Ecological SSLs. Groundwater
analytical results were compared to MDE Groundwater Cleanup Standards for future residential
use of groundwater and to USEPA tapwater RSLs. Sediment results were compared to USEPA
Region III Freshwater Sediment Screening Benchmarks and sediment background levels.
Surface water analytical results were compared to surface water background levels, USEPA
National Ambient Water Quality Criteria (NAWQC) for protection of aquatic life, and MDE
Ecological Screening Criteria. MC investigation results are briefly described below. A summary of
the risk evaluation is presented in Section 2.7.

2.5.5.1 MPRMRS

Nature and Extent of MEC: DGM survey methods were used to identify anomalies and intrusive
procedures were used to investigate anomalies during the Rl. A total of 41 grids covering

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8.7 acres were delineated. One hundred percent of electromagnetic targets within grids were
intrusively investigated. No MEC were found, indicating that there is a low probability of
encountering MEC within the MPR MRS.

Per the DoD Explosive Safety Manual 6055.09-M, a "low probability for encountering MEC
determination" can be made if a search of available historical records and onsite investigation
data indicates that, given the military or munitions-related activities that occurred at the site, the
likelihood of encountering MEC is low. Per the DoD guidance and results of the Rl, the probability
of encountering MEC in the MPR MRS is, therefore, deemed to be "low."

Based on the findings from the Rl and the fact that the Ruggles Golf Course (excluding the greens
and tee boxes) was previously cleared by APG EOD personnel, the potential for MEC to remain
at the MPR MRS is very low.

Nature and Extent of MC: Environmental sampling of soil, surface water, sediment, and
groundwater for MC was also completed during the Rl. The results from both MPR and FDA
MRSs were combined as the MRSs are both located in Ruggles Golf Course.

MC investigation results for each media are briefly described below.

MC in Soil—Surface soil was not considered representative of past military munitions activities at
the MRSs due to the presence of fill material at the golf course. Surface soil samples (0-1 ft bgs)
were not collected to characterize MC; subsurface soil samples (2-6 ft bgs) were collected at
depths that represented the native soil/fill material interface where evidence of past MRS
operations may be encountered. Subsurface soil samples were analyzed for MC (metals and
explosives), and perchlorate. Surface soil samples were also collected from the golf course and
analyzed for perchlorate to assess possible perchlorate contributions from golf course fertilizers.

No explosives compounds above the detection limits were found in any samples collected at the
MPR or FDA MRSs. Perchlorate was detected in only one subsurface soil sample at the FDA
MRS, and the concentration was below the residential human health RSL.

Arsenic and manganese were detected in subsurface soil above human health screening criteria
but were within background ranges. Antimony, chromium, lead, manganese, and mercury were
detected in subsurface soil above ecological SSLs but, as described in Section 2.7, they are not
likely to present an unacceptable ecological risk.

MC in Sediment—Sediment samples were collected from a man-made pond at the FDA MRS and
one man-made pond and its outflow (an intermittent stream) at the MPR MRS. Samples were
analyzed for metals, explosives, and perchlorate. Explosives and perchlorate were not detected.
All metals were within background ranges in sediment.

MC in Groundwater— Groundwater was collected from five existing monitoring wells located both
within and outside of the MRSs. Samples were analyzed for metals, explosives, and perchlorate.
Explosives were not detected. Perchlorate was detected in all five samples below the MDE
residential cleanup standard for groundwater. Aluminum, iron, manganese, and zinc
concentrations were found at levels higher than the human health-based MDE Groundwater
Cleanup Standard but were within background ranges. Aluminum, copper, iron, lead, manganese,
nickel, and zinc were detected in groundwater at concentrations higher than ecological surface
water screening values, but as described in Section 2.7, they are not likely to present an
unacceptable ecological risk.

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MC in Surface Water and Groundwater (via potential interaction with Surface Water)—Surface
water samples were collected from a man-made pond at the FDA MRS and one man-made pond
and its outflow (an intermittent stream) at the MPR MRS. Samples were analyzed for metals,
explosives, and perchlorate. Explosives and perchlorate were not detected. Arsenic was above
human health screening levels in surface water. Aluminum, arsenic, copper, iron, lead
manganese, and mercury concentrations were above ecological screening levels in surface
water, but as described in Section 2.7, they are not likely to present an unacceptable ecological
risk.

2.5.5.2	FDA MRS

Nature and Extent of MEC: DGM survey methods were used to identify anomalies and intrusive
procedures were used to investigate anomalies during the Rl. The geophysical investigation of
the FDA MRS was performed in the former demolition pit and in the area outside of the pit. A
different approach for each area was used. Within the demolition pit, DGM covered 100% of the
5.3-acre area. A total of 450 of the 1,800 geophysical anomalies mapped were intrusively
investigated. A single MEC item was found (81mm illumination mortar). The MEC item was
recovered in the "fill" material that came from other locations on APG. There is no historical
evidence of these types of MEC being fired in this area; therefore, it is unlikely that additional
mortars are present. However, the typical detection depth is roughly 12 times the diameter of the
item so location of small items below the fill may have been beyond the limitations of the
technology. The statistical analysis of the demolition pit area performed for the Rl indicated that
there are fewer than 3.019 MEC/acre with 95.06% confidence; therefore, there is a low probability
of encountering MEC within the demolition pit area of the FDA MRS.

In the area outside of the former demolition pit area, data were collected along randomly placed
transects; all geophysical targets on these transects were intrusively investigated, and no MEC
were found. This indicates that there is a low probability of encountering MEC within the FDA
MRS outside of the demolition pit area.

Based on the findings of the Rl and the fact that Ruggles Golf Course (excluding the greens and
tee boxes) was previously cleared by APG EOD personnel, the potential for MEC to remain at the
FDA MRS is very low.

Nature and Extent of MC: As noted under the MPR MRS, the MC investigation results for both
MRSs were combined because the MRSs are both located in Ruggles Golf Course. See the MPR
MRS Nature and Extent of MC discussion for details.

2.5.5.3	Gas i&D Area MRS

Nature and Extent of MEC: There is no potential for MEC in the Gas l&D Area MRS; therefore, a
MEC investigation was not performed.

Nature and Extent of MC: Soil samples were collected to evaluate whether the historical activities
had impacted the environment. Soil samples were collected for arsenic and mustard breakdown
products. No mustard breakdown products were detected. Arsenic was detected at levels above
human health screening criteria but within background ranges.

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2.5.5.4	Munitions and Explosives of Concern Release Mechanisms

Mechanisms for MEC release at the FDA MRS include the use of the area for training including
deliberate or unintentional detonation of munitions. Munitions discovered at the MRS include HE
loaded projectiles, grenades, fuzes, bombs, boosters, and rockets. Mechanisms for MEC release
at the MPR MRS include the use of the area for firing and training with mines and booby traps,
rifle grenades, hand grenades, and rocket launchers. The locations for potential MEC releases
were established during the SI (Malcom Pirnie 2010) and Rl (ERT 2014). The open detonation
for demilitarization or destruction of ordnance could also contribute to the release of MEC. Fill
material was placed over most of the FDA and MPR MRSs when the golf course was initially
constructed in the 1950s.

2.5.5.5	Interaction with MEC and MC

There are no unacceptable MEC or MC risks to human health and the environment at the Gas
l&D Area MRS; therefore, there is no potential for interaction with MEC and MC at the Gas l&D
Area MRS. In addition, there are no unacceptable MC risks to human health and the environment
at the MPR and FDA MRSs. Therefore, there is no potential for interaction with MC at the MPR
and FDA MRSs.

The potential for interaction between humans and MEC on the surface and near surface (less
than 2 ft bgs) at the MPR and FDA MRSs is considered incomplete. There is a potential for
interaction between authorized base personal/contractors performing intrusive activities and MEC
in the subsurface at the MPR and FDA MRSs. However, human interaction with subsurface MEC
is considered low/potentially complete.

The potential for interaction of ecological receptors with MEC on the ground surface is incomplete.
The potential for interaction of ecological receptors with MEC in the subsurface (greater than 2 ft
bgs), is anticipated to be potentially complete in the FDA and MPR MRSs. Terrestrial habitats at
the MRSs support a limited range of animals, some of which include burrowing activity in their
behavior.

Subsurface disturbances can lead to transport and migration of MEC from one environmental
medium to another. Natural physical influences typically include erosion, precipitation runoff, and
frost heave. Chemical interactions with media or water influx may cause corrosion or leaching of
MEC and may vary with proximity to the surface and surrounding geochemistry of media.

2.6 Current and Potential Future Land Use and Resource Uses

2.6.1 Land Use

The current and reasonably anticipated future land uses were used to evaluate risk (Section 2.7)
and form the basis for reasonable exposure assessment assumptions and risk characterization
conclusions.

According to the APG Land Use Assessment, current land use at APG includes operational range,
research and development, supply/storage, open space, outdoor recreation, administration,
airfield, and industrial uses. Buildings are used for warehousing, offices, and research and
development activities. The current land use of the MPR and FDA MRSs is a golf course
(i.e., Ruggles Golf Course). The future land use is expected to remain consistent with current land
use as Ruggles Golf Course. Surrounding land use includes residential housing, commercial, and
industrial areas. Access to these MRSs is unrestricted.

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During the Rl, the majority of the Gas l&D MRS was being used to stockpile soil associated with
BRAC construction efforts at APG (ERT 2014). The future use of the Gas l&D Area MRS is
anticipated to be the same as the current land use. Access to this MRS is unrestricted.

2.6.2 Groundwater and Surface Water Uses

Harford County production wells, a drinking water source, are in a deep groundwater aquifer more
than 2,000 ft downgradient (west-southwest) of the MPR and FDA MRSs. Some of these wells
have documented solvent contamination from a chlorinated solvent plume that is not associated
with the MRSs. Although a clay layer separates the upper and lower aquifers beneath the MPR
MRS and FDA MRS, it may only be a semi-confining layer as it appears that the aquifers become
interconnected closer to the Harford County production wells.

The City of Aberdeen has a well field of 11 wells located in the northwestern portion of APG, just
north of the Ruggles Golf Course. All these city wells are currently in use. These wells are
hydrogeologically upgradient of the FDA MRS and MPR MRSs and are pumped from a deep
(lower) aquifer (casing depths ranging from 30 to 80 ft bgs) within the Talbot Formation, located
beneath a confined or semi-confined clay layer. The shallow groundwater at the Gas l&D MRS
flows north-northeast; there are no public water supply wells in this direction.

Sites in APG-AA and all of APG-Edgewood Area may have groundwater contamination above
maximum contaminant levels established under the Safe Drinking Water Act. Consequently, the
Harford County Health Department and MDE require that potable groundwater wells be permitted
with the Health Department before installation. Although groundwater from the upper aquifer is
not currently withdrawn for residential use at the APG-AA MRSs, groundwater was identified as
a potentially complete future exposure pathway due to the existence of public water supply wells
in the area.

All surface water systems within APG are linked to the Chesapeake Bay, its tributaries, and
associated wetlands. Modified wetlands and drainages are common throughout the installation.
Small ponds created by military activities and wildlife are a regular feature in the landscape of the
unmanaged portions of APG. Decorative man-made drainage and irrigation ponds are present
at the golf course. Although these water bodies may be used by wildlife such as amphibians, fish,
and birds, an initial site walkover and observations made during the Rl fieldwork indicated low
ecological use of the ponds (ERT 2014).

2.7 Summary of Site Risks

As part of the MMRP Rl, the Army conducted a baseline risk assessment to determine the human
health and ecological risks associated with MC and MEC at the three MRSs. In summary, there
are no unacceptable MC risks to human health and the environment at the MRSs. In addition,
there are no unacceptable MEC risks to human health and the environment at the Gas l&D Area
MRS. A summary of the MC and MEC risk assessment results is included in the following
subsections.

2.7.1 MC Risk Assessment

The baseline risk assessment estimates what MC risks the site would pose if no action were
taken. It provides the basis for taking action and identifies the contaminants and exposure
pathways that need to be addressed by the remedial action. This section of the ROD summarizes
the results of the baseline risk assessment for the site. Soil analytical results were compared to
APG and regional background levels, USEPA residential soil RSLs, MDE Residential Soil

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Cleanup Standards, USEPA Protection of Groundwater SSLs, and USEPA Ecological SSLs.
Groundwater analytical results were compared to MDE Groundwater Cleanup Standards for
future residential use of groundwater. Sediment results were compared to USEPA Region III
Freshwater Sediment Screening Benchmarks and sediment background levels. Surface water
analytical results were compared to surface water background levels, USEPA NAWQC for
protection of aquatic life, and MDE Ecological Screening Criteria.

Human Health Risks: Data that form the basis for the human health risk assessment (HHRA)
were collected during the Rl. The HHRA risk characterization estimated the potential excess
lifetime cancer risk and potential for non-cancer adverse health effects for human receptors
exposed to contaminants of potential concern (COPCs) in soil, surface water, sediment, and/or
groundwater at the three MRSs. Receptors evaluated in the HHRA included installation
personnel, contractors, trespassers, visitors (golfers), and future residents (for groundwater only).
The HHRA concluded that no human health risks are likely to be associated with potential human
contact with COPCs detected in subsurface soil, surface water, or sediments at the three MRSs.
A brief discussion of the media and COPCs follows.

Subsurface Soil—Arsenic was identified as a human health COPC in subsurface soil at all three
MRSs. The maximum soil concentration for arsenic (9.94 milligrams per kilogram [mg/kg]; FDA-
SO-03-03) was found in the FDA MRS. The HHRA indicated that the maximum arsenic
concentrations on the MRSs were greater than MDE residential and non-residential cleanup
standards and the USEPA residential and industrial soil RSLs. However, the HHRA noted that
the MDE recommended soil arsenic level for recreational purposes is 10 mg/kg (MDE 2010 cited
in ERT 2014). Because the concentrations of arsenic at the MRSs were below the recommended
recreational soil value, the HHRA determined that further quantitative risk assessment for arsenic
in soil for the three MRSs was not warranted.

Manganese was identified as a human health COPC in subsurface soil at the MPR MRS and FDA
MRS. The maximum soil concentration of manganese (1,060 mg/kg; MPR-SO-15-04) was found
in the MPR MRS. The maximum detected concentration was greater than the MDE residential
soil cleanup standard but less than the MDE non-residential soil cleanup standard and less than
the USEPA residential soil RSL. As documented in the Rl Report, manganese background 95%
UPL =1,517 mg/kg, while detected subsurface soil manganese is lower with a maximum detected
concentration = 1,060 mg/kg. The USEPA residential soil RSL for manganese in the Rl was
based upon a HQ of 1, while all other metals were based upon an HQ of 0.1. The MDE residential
soil screening value was based upon a HQ of 0.1. Additionally, detected subsurface soil
concentrations were statistically less than site-specific background. Therefore, further quantitative
assessment of manganese in soil was not warranted for the HHRA.

Surface Water—Although surface water (two ponds and one intermittent stream) at the FDA and
MPR MRSs is not used for drinking water or for fishing, arsenic was identified as a human health
COPC in surface water because it was present at a concentration greater than the USEPA
NAWQC. The NAWQC are conservative levels that are used for screening purposes to ensure
the safety of individuals drinking the water and ingesting fish caught in the water. The single
detection of arsenic in surface water (5.96 micrograms per liter [|jg/L]; FDA-SW-01) was greater
than the four detects in background surface water (range of 2.1-3.1 |jg/L, and 95% upper
prediction limit of 1.86 |jg/L, including consideration of non-detects). However, the onsite surface
water concentration of arsenic is not expected to cause adverse human health impacts because
the actual human contact with surface water most likely to occur at the MRSs (e.g., accidental
dermal contact) results in less exposure than would occur via ingestion of water and fish, which
are not expected to happen at the golf course water bodies.

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Groundwater— Manganese and zinc were identified as human health COPCs in groundwater at
the FDA and MPR MRSs because their maximum concentrations were greater than the MDE
Cleanup Standards for Groundwater. Aluminum and iron were also detected above the MDE
Cleanup Standards for Groundwater. A comparison to the tap water RSL reveals that only one
detection of iron within well AARI-MPR-GW-FTA-PZ-02, which had the maximum detected
concentration for all metals. The Rl report noted this sample, "Observations in the field of high
turbidity in this sample indicate that this sample contained suspended particulates (ERT 2014)"
which likely contributed to the tap water RSL and MDE cleanup standards for groundwater.
Therefore, iron and manganese were not selected as COPCs. Although site groundwater is not
planned for future potable use, the potential risks associated with manganese and zinc if the
groundwater were used as drinking water were evaluated in the HHRA. They were evaluated
because all usable groundwater must be restored to beneficial use, regardless of the current use,
and also because of the proximity of several drinking water sources to APG.

Manganese and zinc are not classified as human carcinogens. The potential for non-cancer health
hazards is expressed as a hazard index (HI), which represents the sum of the ratios of the
concentrations of COPCs present at a site to the reference doses for those COPCs at which no
adverse health effects are expected to occur. Therefore, an HI less than or equal to 1 indicates
that no adverse health effects are anticipated to occur. In the HHRA, the maximum concentrations
of COPCs were used to calculate His. For the theoretical scenario of future residential use of
groundwater from beneath the site, the HI was less than 1 for the resident child receptor. For the
adult, the HI was greater than 1 (HI = 1.7), primarily based on the maximum detected
concentration of zinc. However, the maximum detected zinc concentration (16,400 |jg/L;
associated with the MPR MRS and sample AARI-MPR-GW-FTA-PZ-02) is not representative of
actual groundwater exposure concentrations because it is much higher than the rest of the zinc
results and is related to the presence of suspended particulates because the Rl report noted that
the sample was observed to have high turbidity (ERT 2014). Using the next highest concentration
of zinc (40 |jg/L) in the risk calculations for adult residential use of groundwater results in a HI
less than 1. Based on these assessments, human health risk is not likely to be associated with
groundwater under the MPR, FDA, and Gas l&D Area MRSs. In addition, all zinc concentrations
except the maximum were below the MDE Cleanup Standard for Groundwater. For these
reasons, further investigations are not warranted.

Ecological Risks: Data that form the basis for the screening-level ecological risk assessment
(SLERA) were collected during the Rl. The SLERA was developed to evaluate the chemical
contamination risk to wildlife based on direct contact exposures of organisms to the affected
media as well as the potential exposure of wildlife through the ingestion of other organisms as
food sources. Contaminants of potential ecological concern (COPEC) were identified for
subsurface soil and groundwater (via potential interaction with surface water) at the MPR, FDA,
and Gas l&D MRSs and for sediment and surface water at the FDA and MPR MRSs. For benthic
and aquatic organisms, site metals concentrations in sediment and surface water could pose a
potential for risk to individual organisms at the maximum detected concentrations. However, the
maximum detected concentrations are not representative of the exposure concentrations for the
benthic and aquatic organisms in the ponds and stream at the golf course. In addition, for some
constituents, concentrations are similar to background concentrations. In summary, the COPECs
detected in the site media at the three MRSs are not likely to have significant ecological effects.
A brief discussion of the media and COPECs follows.

Subsurface Soil—The concentrations of several metals (antimony, chromium, lead, manganese,
and mercury) in subsurface soil were greater than conservative ecological SSLs. These results

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indicate that there is a potential for ecological effects. Further assessment of subsurface soil was
included in a toxicity reference value (TRV) analysis. Based on the conservative nature of the
screening levels and the assumptions used in the TRV analysis, the detected concentrations of
metals in site subsurface soil are not likely to have adverse ecological effects.

Sediment—The concentration of lead detected in one sediment sample was greater than the
sediment screening level. However, the concentration was less than site-specific background.
Therefore, the risk assessment determined that lead in sediment was not a concern.

Surface Water— Concentrations of aluminum, arsenic, copper, iron, lead, manganese, and
mercury in surface water were above the ecological screening levels; therefore, these metals
were identified as surface water COPECs. Further assessment of the potential for adverse effects
to aquatic organisms from exposure to these metals was conducted by comparing maximum
concentrations to NAWQC or another appropriate benchmark if a NAWQC value was not
available. Maximum concentrations of aluminum, copper, iron, lead, and manganese were
greater than NAWQC. However, with the exception of copper, concentrations of these COPECs
were within the range of site-specific background concentrations. Therefore, the risk assessment
determined that the concentrations of these metals in surface water were not of ecological
concern. While the maximum concentration of copper was greater than the NAWQC and site-
specific background, all other copper concentrations were less than the NAWQC. Because
aquatic organisms will not be exposed to only the maximum concentration, the risk assessment
concluded that adverse effects from exposure to copper throughout the surface water bodies were
unlikely.

Groundwater (via potential interaction with Surface Water)—Concentrations of metals detected in
groundwater were compared to surface water screening levels. Concentrations of aluminum,
copper, iron, lead, manganese, nickel, and zinc in groundwater were above the ecological
screening levels. The highest concentrations of the COPECs were found in a single sample,
which had been observed to have high turbidity and is from a well located outside and
downgradient of the MRSs. An assessment of the groundwater and surface water elevations
indicated that groundwater is unlikely to be affected by surface water. In addition, the ecological
surface water screening levels are developed for the most sensitive aquatic receptors, which are
not likely to be present in groundwater. Thus, the SLERA concluded that groundwater is not likely
to present unacceptable ecological risks at the MRSs.

Ecological Risks Summary—The assessment of the potential for risks to site receptors using
TRVs and with consideration of background levels of metals in soil, sediment, and surface water,
indicated that ecological risks associated with past Army activities are not likely at the Ruggles
Golf Course.

MC Risk Summary: No further action is recommended for MC as the concentration of constituents
are below background, below regulatory standards, and/or do not present an unacceptable risk
to human health or the environment.

2.7.2 MEC Concern Hazard Assessment

An explosive hazard assessment was conducted using the MEC Hazard Assessment (MEC HA)
to assess potential explosive hazards to human receptors. The MEC HA structure assigns
numeric values associated with input factors to generate scores describing the hazards
associated with MEC. The MEC HA technical framework consists of three elements: Input
Factors, Structure, and Output (USEPA 2006, 2008a). This framework uses information in terms

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of explosive hazard components and assigns weighting factors to score the combination of input
factors, resulting in an output describing the explosive hazard level category of the MRSs. The
MEC HA is structured around three components of a potential explosive hazard incident:

•	Severity: The potential consequences (e.g., death, severe injury, property damage) of
MEC detonating

•	Accessibility: The likelihood that a receptor will be able to encounter MEC

•	Sensitivity: The likelihood that a receptor will be able to interact with MEC such that it will
detonate.

The MEC HA methodology was used during the Rl (ERT 2014).

MEC Risk Summary:

MPR MRS—No evidence of MEC was found on the MPR MRS during the Rl; therefore, a MEC
HA was not performed.

FDA MRS—One MEC item was recovered in the FDA MRS demolition pit. The MEC HA included
the 81mm illumination round found during the Rl as well as a 105mm HE projectile, which was
the munition with the greatest fragmentation distance (MGFD) identified in the Explosives Site
Plan (ERT 2012) and the largest of the items historically found at the MRS. The MEC HA includes
a worst-case evaluation of the potential MEC items historically found and, therefore, potentially
present at the MRS. The FDA MRS scored 640, Hazard Level 3 (moderate hazard potential). The
MRS score is a function of the size and location of the one MEC item found during the Rl.

Gas l&D Area MRS—There is no potential for MEC at the Gas l&D Area MRS; therefore, a MEC
HA was not performed.

The MEC CSM (Figure 3) indicates that there is a potentially complete exposure pathway for MEC
in the subsurface of the MPR and FDA MRSs for intrusive activities by construction workers. The
results of the Rl and FS indicate that further action is necessary to address MEC contamination
in the MPR and FDA MRSs.

2.7.3 Basis for Taking Action

MC: No action is recommended for MC in the three MRSs as no human health risk or ecological
risks were identified.

MEC: No action is recommended for MEC in the Gas l&D Area MRS as no explosive hazards
were identified. Further action is necessary to protect public health or welfare from potential MEC
hazards in the MPR and FDA MRSs.

2.8 Remedial Action Objectives

There are no unacceptable MEC or MC risks to human health and the environment at the Gas
l&D Area MRS; therefore, no actions are required, and Remedial Action Objectives (RAOs) were
not developed for that MRS. The Gas l&D Area MRS is excluded from Section 2.9 through
Section 2.13 in accordance with the USEPA guidance for completion of RODs.

There are no unacceptable MC risks to human health and the environment at the MPR and FDA
MRSs; therefore, RAOs for MC were not developed.

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The general goal of a MEC remedial action is to reduce explosives hazards to ensure the
protection of human health, public safety, and the environment. The specific RAO for the MPR
MRS and FDA MRS is:

Prevent public, APG personnel, contractor/maintenance worker, visitors/trespasser, and
recreational user exposure to MEC while maintaining the intended future land use of a golf
course.

2.9 Description of Alternatives

This section summarizes the two remedial action alternatives for the MPR and FDA MRSs that
were analyzed in the FS (Bay West LLC 2017). These alternatives are listed in Table 6 and are
summarized in Sections 2.9.1 and 2.9.2.

Table 6. MPR and FDA MR

.S Remedial Action Alternatives

Designation

Description

Alternative 1

No Action

Alternative 2

Land Use Controls

A third alternative, MEC Clearance to Achieve UU/UE, was also evaluated in the screening of
alternatives but was not retained for detailed analysis and comparative analysis against other
alternatives in the FS. Under Alternative 3, every effort would be made to find, remove, and
destroy any MEC that remains below the ground at the MRSs. However, complete removal may
not be possible with current technologies due to the historical placement of fill material, which
would limit the ability to locate MEC at its anticipated depth as well as beneath existing buildings
and other improvements. Furthermore, the anticipated costs to achieve UU/UE through MEC
clearance would be very high. The risk of MEC encounters after removal would be very low but
not zero. As such, LUCs would still be required for the alternative to be protective. Therefore,
because the costs associated with Alternative 3 would be excessive compared to its overall
effectiveness and implementability, Alternative 3 was not retained in the FS for detailed analysis.

2.9.1	Alternative 1—No Action

In accordance with the NCP, a No Action alternative must be developed as a baseline to compare
against other alternatives. In a CERCLA FS evaluation, a No Action alternative equates with a
determination to do no remediation and place no controls on land use or activities on the property.
The No Action alternative also does not consider any existing controls, if present. Site access is
assumed to be unrestricted and there are no limitations on current or future site use or activities.
Therefore, Alternative 1, No Action, involves no active response or controls to locate, remove,
dispose of, or limit the exposure to any MEC potentially present at the MRS. This alternative
provides a baseline for comparison of other response alternatives. It assumes continued use of
the MRS in its present state. If the potential exposure and hazards associated with the MRS are
compatible with current and future developments in the area, then No Action may be warranted.
The Army would respond to any future MEC discovery, regardless of whether the MRS is
designated for No Action.

2.9.2	Alternative 2—Land Use Controls for the MPR and FDA MRSs

Alternative 2 includes legal and education LUCs to manage remaining hazards at the MPR and
FDA MRSs. The hazard is MEC potentially present at 2 ft bgs or greater. No additional active
remediation would be performed at the MRSs. The LUCs include:

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•	Legal Controls

—	Safety Excavation Permit Program

—	Prohibition on Residential Use

—	Contractor Control Policies

—	Construction Support

•	Educational Outreach

—	Public Notices

—	Community Awareness Meetings

—	Letter Notifications, Informational Pamphlets, and Fact Sheets

—	Formal Education Sessions.

The MRSs will be formally incorporated into the APG Base Master Plan and review process, which
includes a review of any construction plans and construction support. UXO support for any
construction or other intrusive activities will be required. Because subsurface MEC may remain,
training and awareness programs will be implemented, annual inspections will be performed, and
CERCLA Five-Year Reviews will be conducted to assess the site condition and whether the
remedy remains protective of human health and the environment. No residential development of
the property will be permitted. An MRS Prioritization Protocol (MRSPP) Annual Update will be
prepared, in accordance with the requirements of 32 Code of Federal Regulations (CFR)
Part 179.

The LUC alternative focuses on reducing human exposure to MEC by managing the activities
occurring at the MRSs. It will include:

•	Access and land use restrictions that limit access and restrict activities

•	Administrative controls on land use through deed and zoning restrictions

•	Educational information to manage and reduce community exposure to hazards

•	Construction support requirements.

The MRSs will be formally incorporated into the APG Base Master Plan and review process, which
includes a review of any construction plans and construction support. The MPR and FDA MRSs
will remain at their current status, which consists of MEC potentially present at 2 ft bgs or greater.
No remediation will be performed at the MRSs.

2.10 Comparative Analysis of Alternatives

A detailed analysis of the individual alternatives was performed and considered each of the nine
evaluation criteria specified in NCP §300.430(e)(9)(iii); this analysis is summarized in Table 7.
The major objective is to evaluate the relative performance of the alternatives with respect to the
nine evaluation criteria so that the advantages and disadvantages of each are clearly understood.
The nine evaluation criteria fall into three groups, threshold criteria, primary balancing criteria,
and modifying criteria:

•	Threshold criteria are requirements that each alternative must meet to be eligible for
selection.

•	Primary balancing criteria are used to weigh major trade-offs among alternatives.

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• Modifying criteria may be considered to the extent that information is available during the
RI/FS but are fully considered only after public comments are received on the Proposed
Plan.

A comparative analysis was then performed so that the advantages and disadvantages of each
alternative could be examined relative to each other and so that key differences in the alternatives
could be identified, thus providing a framework for selection of an appropriate remedy for the site.

This section summarizes how well each alternative satisfies each evaluation criterion and
indicates how each alternative compares to the other. A relative ranking of the alternatives
against the nine criteria is shown in Table 8, followed by a brief discussion for each criterion. A
detailed description can be found in the FS Report (Bay West LLC 2017).

	Table 7.	Evaluation Criteria for Superfund Remedial Alternatives	

	THRESHOLD CRITERIA	

Overall Protection of Human Health and the Environment determines whether an
alternative adequately eliminates, reduces, or controls threats to public health and the

environment through institutional controls, engineering controls, or treatment.	

Compliance with Applicable or Relevant and Appropriate Requirements (ARARs)
evaluates whether an alternative meets the requirements of Federal and more stringent State
environmental statutes and regulations, other State facility siting laws, and other requirements

to be considered (TBC) that pertain to the site, or whether a waiver is justified.	

	PRIMARY BALANCING CRITERIA	

Long-Term Effectiveness and Permanence considers the ability of an alternative to

maintain protection of human health and the environment over time.	

Reduction of Toxicity, Mobility, or Volume of Contaminants through Treatment
evaluates the degree to which an alternative uses treatment to reduce the harmful effects of
principal contaminants, their ability to move in the environment, and the amount of

contamination present.	

Short-Term Effectiveness considers the length of time needed to implement an alternative
and the risks the alternative poses to workers, the community, and the environment during

implementation.	

Implementability considers the technical and administrative feasibility of implementing an

alternative, including factors such as the relative availability of goods and services.	

Cost includes estimated capital and annual operation and maintenance (O&M) costs, as well
as present worth cost. Present worth cost is the total cost of an alternative over time in terms
of today's dollar value. Cost estimates are expected to be accurate within a range of +50% to

-30%.	

	MODIFYING CRITERIA	

State Acceptance considers whether MDE, as the support agency, agrees with the Army's
and the USEPA's analyses and recommendations, as described in the FS and Proposed

Plan.	

Community Acceptance considers whether the local community agrees with the Army's and
USEPA's analyses and preferred alternative. Comments received on the Proposed Plan are
an important indicator of community acceptance.	

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Table 8.	Comparative Analysis of Remediation Alternatives

Screening Criterion

Alternative 1:
No Action

Alternative 2:
LUCs

Overall Protection of Human Health and the
Environment

No

Yes

Compliance with ARARs

Not evaluated (a)

Not applicable

Long-Term Effectiveness and Permanence

Not evaluated (a)

•

Reduction of Toxicity, Mobility, and Volume (TMV)
through Treatment

Not evaluated (a)

0

Short-Term Effectiveness

Not evaluated (a)

•

Implementability

Not evaluated (a)

•

Cost

Not evaluated (a)

$45,572

State Acceptance

Not evaluated (a)

Yes

Community Acceptance

Not evaluated (a)

Yes

(a) Not evaluated because the No Action alternative was determined to not be protective of human
health, which is one of the threshold criteria.

• Favorable (Yes for threshold criteria).

0 Moderately Favorable (Partially meets threshold criteria)
o Not Favorable (No for threshold criteria).





2.10.1	Threshold Criteria

Overall Protection of Human Health and the Environment: Alternative 1 would not be
protective because no action would be taken to prevent human exposure to potential MEC. The
MPR MRS has a low hazard potential because no MEC was observed at the MRS during Rl
activities. Although the probability is low, it is not zero, as MEC could be encountered during
intrusive activities (i.e., utility work or construction). Therefore, current or future potential risks to
human health or the environment from MEC would not be prevented under Alternative 1. As a
result, Alternative 1 would not meet this criterion.

Alternative 2 would not impact the potential presence of MEC, but legal and educational programs
and construction support would represent an effective control measure to prevent potential
contact by human receptors with MEC at the MRSs. Through LUCs, Alternative 2 would provide
protection of human health and the environment by eliminating, reducing, and/or controlling the
threat of exposure during intrusive activities and would prevent unacceptable changes to the land
use, should they be proposed.

Because Alternative 1 (No Action) does not meet this threshold criterion, it is not evaluated against
the other NCP criteria.

Compliance with ARARs and TBCs: There are no chemical-specific, location-specific, or action-
specific ARARs associated with MEC for the LUC alternative. However, should MEC be identified
during construction support activities, it will be handled in accordance with the ARARs in Table 9.

2.10.2	Balancing Criteria

Long-Term Effectiveness and Permanence: Alternative 2 would be effective and permanent,
assuming the cooperation and active participation of the Army's tenants. The LUCs required

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under Alternative 2 would be effective in preventing human exposure to MEC presenting an
unacceptable risk in the long-term.

Reduction of TMV through Treatment: Reduction of TMV through treatment refers to the
anticipated performance of the treatment technology used in a remedy. Toxicity is generally not
applicable to MEC. Alternative 2 would not reduce the TMV of MEC through treatment, and
therefore does not satisfy this criterion. If MEC were identified during construction support
activities only a very minor reduction in TMV through treatment, if any, would occur.

Short-Term Effectiveness: For Alternative 2, LUCs can be put into place within 6 months to
achieve the RAO, and no MEC removal actions would be taken so there would be no short-term
risks to the community or workers. If MEC were identified during construction support activities,
engineering controls would be implemented to protect the community and site workers.

Table 9.	Summary of ARARs for the MPR and FDA MRSs

ARAR

Citation Description

Applicability

Chemical-Specific

None
identified

Not applicable

Not applicable

The HHRA and SLERA
demonstrated that COPCs and
COPECs present in subsurface
soil, sediment, groundwater, and/or
surface water at the FDA and MPR
MRS do not pose unacceptable risk
to human health or the
environment. Therefore, there are
no chemical-specific ARARs.

Location-Specific

None
identified

Not applicable

Not applicable

No location-specific ARARs are
identified for APG-AA.

Action-Specific

Environmental

Performance

Standards

Subpart X -
Miscellaneous Units:
40 CFR 264.601

Miscellaneous units will
be required to be
located, designed,
constructed, operated,
maintained, and closed
in a manner that will
prevent any release
that may have adverse
effects on human
health and the
environment.

Relevant and Appropriate
Relevant and Appropriate if actions
require treatment of explosives by
open detonation.

Sampling and
Analysis

40 CFR 261
Code of Maryland
Regulations
(COMAR)
26.13.03.02
40 CFR 136, App. A,
(SW-846sampling
methods)

Specific requirements
for identifying
hazardous wastes.
Establishes analytical
requirements for
testing and evaluating
solid, hazardous, and
water wastes.

Applicable

Applicable should sampling be
required at the MRSs for any
reason in the future. These
standards apply to identifying
hazardous waste.

General
Remediation

40 CFR 262
COMAR 26.13.03.02

Establishes standards
for generators of
hazardous waste.

Applicable

Applicable if hazardous waste is
identified.

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Implementability: The legal and administrative LUCs required under Alternative 2 would be
implementable and some LUCs are already in place and could be easily augmented.

Cost: The estimated costs for Alternative 2 are listed in Table 10 and Appendix C.

Table 10. Summary of Costs

Alternative No.

Capital Costs

30-Year O&M Costs

Net Present Worth

1

$0

$0

$0

2

$2,911

$42,661

$45,572

2.10.3 Modifying Criteria

State Acceptance: MDE reviewed and provided comments on the Final FS Report and Proposed
Plan. MDE has expressed their support for Alternative 2 (Appendix A).

Community Acceptance: During the public comment period on the Proposed Plan, no written
comments were submitted to APG from the public. During the Proposed Plan public meeting, no
attendees presented comments or questions (Appendix D). Therefore, the Army concludes that
the community accepts the preferred remedy as specified in the Proposed Plan.

2.11	Principal Threat Wastes

The NCP states a preference for using (to the extent practicable) treatment that reduces the TMV
of the principal threat wastes. The principal threat concept refers to source materials present at a
CERCLA site that are considered to be highly toxic or highly mobile and that generally cannot be
reliably controlled in place or that would present a significant risk to human health or the
environment should exposure occur. MEC do not meet the definition of principal threat wastes as
migration of these materials from the MPR or FDA MRSs is neither occurring nor is it anticipated.
Therefore, there are no principal threat wastes at the MRSs.

2.12	Selected Remedy

The Army has selected Alternative 2, LUCs, to manage the remaining hazard at the MPR and
FDA MRSs. The hazard is MEC potentially present at 2 ft bgs or greater. No remediation will be
performed at the MRSs. However, should MEC be identified during construction support activities,
it will be handled in accordance with the ARARs in Table 9. Successful implementation of LUCs
is contingent upon the cooperation and active participation of the Army's tenants to protect the
public from explosives hazards. The M RSs will be formally incorporated into the APG Base Master
Plan and review process, which includes a review of any construction plans and construction
support. Long-term implementation of LUCs are the responsibility of the Army. The future land
use of the MPR and FDA MRSs as Ruggles Golf Course is expected to remain consistent with
current land use. The selected remedy is intended to be the final remedy for the MRSs and does
not impact any other areas at the Installation.

The Army has also selected No Action as the final remedy for the Gas l&D Area MRS as there
are no unacceptable risks to human health or the environment associated with the military use of
the property and it meets the conditions for UU/UE.

The Army is responsible for implementing the selected remedies specified in this ROD. The Army
will exercise their responsibility in accordance with CERCLA and the NCP. A description of the
selected remedy for the MPR and FDA MRSs is presented in this section. In accordance with

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USEPA guidance, the No Action decision for the Gas l&D Area MRS is not discussed in this
section.

2.12.1	Summary of the Rationale for the Selected Remedy

Based on the information currently available, the Army believes the selected remedy meets the
threshold criteria and provides the best balance of tradeoffs among the other alternatives with
respect to the balancing criteria. The Army expects the selected remedy to satisfy the following
statutory requirements under CERCLA § 121(b): 1) to be protective of human health and the
environment; 2) to comply with ARARs; 3) to be cost-effective; 4) to utilize permanent solutions
and alternative treatment technologies or resource recovery technologies to the maximum extent
practicable; and 5) to satisfy the preference for treatment as a principal element (or justify not
meeting the preference). The preferred alternative does not meet the preference for treatment
as a principal element; given the low probability of MEC remaining below the ground, finding and
destroying the MEC would not be cost effective. Any potential hazards can be reliably controlled
using LUCs.

2.12.2	Description of Selected Remedy

LUCs focus on reducing human exposure to MEC by managing the activities occurring at the
MRSs. The LUC boundary will consist of the MRS boundaries outlined in Figure 4. The MRSs
are maintained areas with no history of MEC being found on the ground surface due to migration
from the subsurface. In addition, the MRSs were cleared to 2 ft bgs by EOD personnel, other than
the greens and tee boxes. Therefore, the potential for migration of MEC, which has never been
reported in the past, is considered unlikely. The Rl confirmed that the probability of MEC
encounters is low. Based on information currently available, the LUC remedy provides the
greatest benefit for the expected costs and meets the RAO. The selected remedy is necessary to
protect public health and welfare or the environment from potential exposure to potential MEC.

The boundaries for the MPR MRS and FDA MRS LUCs are the MRS boundaries depicted on
Figure 2. The Army is responsible for implementing, maintaining, reporting on, and enforcing the
LUCs. Transfer of this responsibility is not expected; however, if the Army does transfer these
procedural responsibilities to another party by contract, property transfer agreement, or through
other means, the Army shall retain ultimate responsibility for remedy integrity.

APG's existing LUCIP will be updated to include details for implementation of LUCs at the MRSs.
This plan provides an extensive list of practices that are applicable to the entire installation and
specific LUCs implemented by the Installation where land is unsafe for UU/UE. LUCs that will be
implemented for the MPR and FDA MRSs include legal and educational controls, as described
below.

Legal Controls:

• Safety Excavation Permit Program: APG Regulation 385-7 addresses requirements for
MEC construction support during excavation and other intrusive work throughout APG.
The APG Base Master Plan and the geographical information system (GIS) will be
annotated to show that LUCs are required at these APG-AA MRSs. The Master Plan will
be used to review proposed actions in the APG-AA MRSs. In conjunction with this, the
APG Directorate of Public Works will review the Base Master Plan and GIS to determine
whether future projects are consistent with the LUCs at the MPR and FDA MRSs.

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• Contractor Control Policies: Contractors performing intrusive activities on the MRSs that
have the potential to contact MEC will be required to receive training. The DoD educational
message for explosive safety is referred to as "the 3Rs": Recognize, Retreat, and Report
any munitions that are encountered while performing maintenance, improvement, or
construction activities on their property.

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Figure 4 - Munitions Response Sites LUC Boundaries Aberdeen Area, Aberdeen Proving Ground, MD

Legend

^ Monitoring Well
A Survey Monument
Road

	 Phillips AAF

	 Stream

|_7" j Historic Demo Pit
I I LUC Boundary
-- New Buildings
¦ (2011)

Soil Pile (2011)
Pond

Golf Fairways
Building
[ a Wooded Areas

Area Shown
in Main Map

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•	Construction Support: When intrusive activities occur at the MRSs, UXO construction
support will be performed. Discussions with APG staff indicated that they have provided
UXO construction support activities at the MRSs in the past and will continue to do so as
needed. UXO construction support will be used to ensure the safety of workers and the
public if MEC items are discovered at the MRSs. In accordance with DoD 6055.09-M (DoD
2008), the level of construction support changes in relation to the location and the
probability for encountering potential MEC. Each activity occurrence will be reviewed with
the APG Safety Office through the safety excavation permit program to ensure the
appropriate support is provided based upon the type of activity planned. As the MPR and
FDA MRSs have been determined to have a low probability of encountering MEC, it is
anticipated that UXO-qualified personnel will provide support either on an on-call basis to
respond to MEC that were incidentally encountered, or on a standby basis to monitor
construction activities.

Educational Controls: Educational outreach will comply with the APG Community Relations

Plan (CRP) that is periodically reviewed (every 5 years) for effectiveness in reaching the public.

•	Public Notices: In accordance with 40 CFR § 300.430(f)(6), notices will be placed in the
local newspapers to notify the public of selection of a final remedy and if any changes to
the remedy occur.

•	Community Awareness Meetings: APG has a Restoration Advisory Board (RAB). The
RAB works with APG on matters related to APG's environmental cleanup program. The
RAB's responsibilities include reviewing Army documents and plans, working with the
Army to develop cleanup priorities, and sharing information with and soliciting feedback
from members of the community. The RAB meets six times per year and is open to the
public.

•	Letter Notifications. Informational Pamphlets, and Fact Sheets: Development and
distribution of informational materials to periodically provide awareness to property owners
and town authorities of the presence of munitions. Informational materials are developed
and shared annually beginning at the onset of LUC implementation and distribution is later
reduced to once every 5 years if the reduced schedule is determined to be acceptable
during the 5-year review. In addition, informational materials will be made available to
users of the golf course.

•	Formal Education Sessions: Formal educational sessions will be held to train employees
(e.g., grounds crew) at the golf course on the recognition of munitions and procedures to
follow should MEC be identified.

2.12.3	Annual Inspections

The Army will ensure that annual inspections are performed to evaluate the effectiveness of the

LUCs. The details of the annual inspections will be specified in the LUCIP as part of the Remedial

Action Work Plan. Inspection forms will be completed during each annual inspection, and the

findings of the inspections will be summarized in annual LUC inspection reports.

2.12.4	Comprehensive Environmental Response. Compensation, and Liability Act Five-Year
Reviews

The potential for MEC remains under the selected remedy for the MPR and FDA MRSs.

Therefore, CERCLA requires the review of the remedial action no less than every 5 years to

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determine if the selected remedy for the MRSs continues to be protective of human health and
the environment. The 5-year reviews will include an assessment of the data generated in the
annual inspections, an assessment of the effectiveness of the CRP, site interviews, a site
visit/inspection, and a report documenting the results of the review. The report may include
recommendations for additional actions or modifications to the management approach, as
necessary.

Recurring reviews will be completed by the Army and will include the following general steps:

•	Prepare Recurring Review Plan

•	Establish project delivery team and begin community involvement activities

•	Review existing documentation

•	Identify/review new information and current site conditions

•	Prepare preliminary Site Analysis and Work Plan

•	Conduct site visit

•	Prepare Recurring Review Report.

2.12.5	Summary of Estimated Remedy Costs

A detailed cost estimate from the FS (Bay West LLC 2017) is provided in Appendix C and is based
on the best available information regarding the anticipated scope of the selected remedy. A
summary of the estimated costs associated with implementation of the selected remedies is as
follows:

•	Capital Costs: $2,911

•	30-YearO&M: $42,661

•	Net Present Worth: $45,572.

The Office of Management and Budget Circular A-94 was updated in November of 2016, signed
on December 12, 2016, and the Real Discount Rate for a 30-year Treasury Note or Bond is 0.7%.
Estimated project costs may go up or down depending on this rate. LUCs and annual inspections
were developed in the FS to assist in developing estimated costs. The legal and education
outreach program, and inspection components will be specified in the work plans (remedial action
work plan, LUC plan, CRP, long-term monitoring and maintenance plans). Changes in the cost
elements may occur as a result of new information and data collected during the implementation
of the selected remedy. Major changes to the selected remedy will be documented in the form of
a memorandum in the Administrative Record file, an Explanation of Significant Differences, or a
ROD Amendment, as appropriate. This is an order-of-magnitude engineering cost estimate that
is expected to be within +50% to -30% of the actual project cost.

2.12.6	Expected Outcomes of Selected Remedy

Implementation of the selected remedy will address the immediate exposure risks to potential
subsurface MEC in the MPR and FDA MRSs. Currently, the FDA MRS scored 640, Hazard
Level 3 (moderate hazard potential) based on one MEC item recovered in the FDA MRS
demolition pit. The MEC HA included the 81mm illumination round found during the Rl as well as
a 105-mm HE projectile, which was the largest of the items historically found at the MRS. Since
no additional active remediation will be performed at the MRSs, the MEC HA score will not
change. Therefore, UU/UE will not be achieved.

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Implementation of the selected remedy will support the current and reasonably anticipated future
land uses as described in Section 2.6. LUCs will provide measures to inform the public and site
users about avoidance of MEC. Annual inspections will be performed, including surveying the
site for MEC items that may have migrated to the surface because of erosion, frost heave, or
stream transport, minimizing the potential for future contact between MEC and human receptors.
Construction support with MEC clearance and CERCLA Five-Year Reviews will be performed to
determine if the selected remedy is and will remain protective of human health and the
environment.

2.12.7	Green Remediation

Green remediation is the concept of reducing the environmental impacts of common investigation
and remediation activities. The application of green remediation options involves identifying best
management practices (BMPs) that are applicable to the project and the phase of the project, as
well as evaluating more sustainable alternatives. There is a multitude of environmental, social,
and economic BMPs that can be applied to the different phases of remediation. Consistent with
the USEPA guidance, Green Remediation: Incorporating Sustainable Environmental Practices
into Remediation of Contaminated Sites (USEPA 2008b), and Methodology for Understanding
and Reducing a Project's Environmental Footprint (USEPA 2012), the Army will evaluate the use
of sustainable technologies and BMPs with respect to any remedial alternative selected for the
site. In addition, the Army will review the Maryland Department of Labor and Industry BMPs when
considering remediation alternatives at the MRSs. Examples are as follows:

•	Minimize impacts to natural resources

•	Identify recycling and reuse options

•	Maximize renewable energy use

•	Use local labor and resources

•	Reuse unimpacted soil

•	Use clean diesel fuel and technologies

•	Reduce greenhouse gas emissions

•	Use low carbon technologies

•	Develop a materials management plan

•	Utilize refurbished equipment when feasible.

2.12.8	Remedial Design

A LUC Remedial Design will be prepared as the land use component of the Remedial Design.
Within 90 days of ROD signature, the Army shall prepare and submit to EPA for review and
approval a LUC remedial design that shall contain implementation and maintenance actions,
including periodic inspections.

2.13 Statutory Determinations

This section confirms that the selected remedy attains the mandates of CERCLA § 121 and, to
the extent practicable, the NCP. Under CERCLA § 121 and NCP § 300.430(f)(5)(ii), the lead
agency must select a remedy that protects human health and the environment, complies with
ARARs, is cost-effective, and uses permanent solutions and alternative treatment technologies
or resource recovery technologies to the maximum extent practicable. In addition, CERCLA also
includes: 1) a preference for remedies that employ treatments that permanently and significantly
reduce the TMV of hazardous substances, pollutants, or contaminants and 2) a preference for
practical treatment technologies versus offsite disposal of untreated wastes. Periodic 5-year
reviews are required if the remedy will result in hazardous substances remaining in place above

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levels allowing for UU/UE. The following sections discuss how the selected remedy meets these
statutory requirements.

2.13.1	Protection of Human Health and the Environment

The selected remedy (Alternative 2, LUCs) will protect human health and the environment by
mitigating contact with potential residual subsurface MEC. No MC hazards or risks to the
environment are present at the MRSs.

2.13.2	Compliance with Applicable or Relevant and Appropriate Requirements

As discussed in Section 2.10.1, remedial actions must comply with both federal and state ARARs.
There are no chemical-specific, location-specific, or action-specific ARARs associated with MEC
for the LUC alternative. However, should MEC be identified during construction support activities,
it will be handled in accordance with the ARARs in Table 9.

2.13.3	Cost Effectiveness

In the Army's judgment, the selected remedy is cost-effective and represents a reasonable value
for the money to be spent. In making this determination, the following definition was used: "A
remedy shall be cost-effective if its costs are proportional to its overall effectiveness" [40 CFR
300.430(f)(1)(ii)(D)]. Overall effectiveness was evaluated by assessing three of the five balancing
criteria used in the detailed analysis of the alternatives: 1) long-term effectiveness and
permanence, 2) reduction in TMV through treatment, and 3) short-term effectiveness. Overall
effectiveness was then compared to costs to determine cost-effectiveness. The relationship of the
overall effectiveness of the selected remedy was determined to be proportional to its costs.
Therefore, the selected remedy represents a reasonable value for the money to be spent. The
estimated net present value of capital and O&M costs of the selected remedy (in 2016 dollars) is
$45,572.

2.13.4	Utilization of Permanent Solutions and Alternative Treatment Technologies to the
Maximum Extent Practicable

The Army has determined that the selected remedy represents the maximum extent to which
permanent solutions and treatment technologies can be utilized in a practicable manner at the
MRSs. The Army has determined that the selected remedy provides the best balance of trade-
offs in terms of the five balancing criteria, while also considering the statutory preference for
treatment as a principal element and bias against offsite treatment and disposal and considering
State and community acceptance. The NCP recognizes that some contamination problems will
not be suitable for treatment and permanent remedies. For the MPR and FDA MRSs, there is no
permanent treatment other than physical removal of the potential residual MEC should MEC be
found during construction support activities.

The selected remedy for the MRSs addresses potential residual MEC in subsurface soils, which
is the hazard at the MRSs. The selected remedy satisfies the criterion for long-term effectiveness
by maintaining LUCs that have been historically effective and reliable and are expected to remain
so in the future. The effectiveness of the existing LUCs will be enhanced under the selected
remedy. The selected remedy does not present short-term risks. There are no special
implementability issues associated with the selected remedy. While the selected remedy does not
provide a permanent solution, MEC discovered at the MRSs will be removed permanently. LUCs
will be required indefinitely or until such a time as it is determined that there are no residual
hazards present. Alternative treatment technologies were not applicable to the MRSs.

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2.13.5	Preference for Treatment as a Principal Element

The NCP establishes the expectation that treatment will be used to address the principal threats
posed by a site wherever practicable—40 CFR 300.430(a)(1)(iii)(A). The selected remedy for the
MPR and FDA MRSs does not provide for treatment; however, as anomalies are discovered
during construction support activities, they are removed after inspection by APG EOD personnel.
Consequently, a minor reduction in MEC, if present, may occur during implementation of the
selected remedy. Treatment technologies for MEC were not recommended because the low
probability of MEC remaining below the ground makes finding and destroying the MEC
prohibitively expensive. Any remaining hazards can be reliably controlled using LUCs.

2.13.6	Five-Year Review Requirements

Because hazards may remain in the MPR and FDA MRSs that do not allow for UU/UE, CERCLA
Five-Year Reviews will be conducted to assess the implementation and performance of the
remedy to determine whether the remedy continues to remain protective of human health and the
environment. Therefore, in accordance with NCP § 300.430(f)(4)(H), a statutory review will be
conducted within 5 years of initiation of remedial action to ensure that the remedy is, or will be,
protective of human health and the environment.

2.14 Documentation of Significant Changes

The Proposed Plan for the MRSs was released for public comment on 18 March 2022. The
Proposed Plan identified Alternative 2—LUCs—as the selected remedy for the MPR and FDA
MRSs to address the MEC hazards. The Proposed Plan also documented No Action for the Gas
l&D Area MRS. The public did not provide comments on the Proposed Plan that led to a change
in the selected remedies. Thus, it was determined that no significant changes to the Preferred
Alternatives, as originally identified in the Proposed Plan, were necessary or appropriate.

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3.0 RESPONSIVENESS SUMMARY

This section provides a summary of the public comments regarding the preferred alternative
presented in the Proposed Plan for the APG-AA MRSs and the Army's response to those
comments. At the time of the public review period, the Army's preferred alternative was
Alternative 2, LUCs, for the FDA and MPR MRSs to address the MEC hazards. The Proposed
Plan also documented No Action for the Gas l&D Area. No changes to the preferred alternatives
were made as a result of the public comments received.

3.1	Stakeholder Comments and Lead Agency Responses

The Proposed Plan for the FDA, MPR, and Gas l&D Area MRSs was made available to the public
on 18 March 2022. The availability of this document was published in the Aegis, the Cecil Whig,
and the Kent County News, on 18 March 2022 (Appendix B) with a 30-day public comment period
from 21 March 2002 to 20 April 2022.

The Army and USEPA have consulted with MDE, the support regulatory agency, and they concur
with the selected remedy. A copy of the MDE letter is included in Appendix A.

One written comment on the PP was received from MDE during the public comment period. A
summary of the comment and the Army's response are presented below; the complete comment
and response are provided in Appendix D. No other written comments were received during the
public comment period, and no comments were received during the public meeting. There were
no major issues raised by stakeholders during the public comment period or during the public
meeting. Therefore, there were no changes to the preferred alternative. Details on the
implementation of the selected remedy will be specified in work plans (i.e., updates to the APG
LUCIP and CRP). Stakeholders will be invited to participate in planning meetings for the
development and review of these plans.

MDE provided one written comment on the PP on 15 April 2022 (Appendix D). The comment
discusses MDE's Cleanup Standards for Soil and Groundwater and USEPA's RSLs, both of which
are mentioned in the PP. The comment asks that references to the MDE Cleanup Standards be
removed and that the USEPA RSLs be referenced instead. The Army's response indicates that
the PP mentions the MDE Cleanup Standards when summarizing the findings of historical
investigations because the Cleanup Standards are comparison values used in those
investigations. The historical investigations, particularly the human health risk assessments, also
used USEPA RSLs. Because the PP is summarizing historical documents and the comparison
values used in the historical documents, no changes to the PP were made.

3.2	Technical and Legal Issues

No technical or legal issues regarding the Proposed Plan were identified during the public meeting
and/or public comment period. This ROD will be added to the Administrative Record file after it is
signed. In addition, a notice of the availability of the ROD will be published in the Aegis, the Cecil
Whig, and the Kent County News in accordance with NCP § 300.430(f)(6).

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4.0 REFERENCES

Aberdeen Proving Ground (APG). 2008. Preliminary Assessment: Former Demolition Area at
Ruggles Golf Course.

Bay West LLC. 2017. Military Munitions Response Program Feasibility Study Aberdeen Proving
Ground - Aberdeen Area Munitions Response Sites. June.

Department of Defense (DoD). 2008. DoD Manual 6055.09-M, DoD Ammunition and Explosives
Safety Standards, Volume 8, Glossary. 29 February.

EA Engineering, Science, and Technology, Inc.. 2011. Aberdeen Proving Ground Western
Boundary Study Area, Operable Units 2 and 3 Remedial Investigation Report. Draft Final.
February.

ERT, Inc. (ERT). 2012. MMRP Remedial Investigation Work Plan. Remedial Investigation,
Aberdeen Proving Ground - Aberdeen Area, Harford County, Maryland. January.

ERT. 2014. Final MMRP Remedial Investigation Report, Multi-Purpose Range, Former
Demolition Area, and Gas Identification and Detonation Area at Aberdeen Proving Ground-
Aberdeen Area, Harford County, Maryland. December.

Malcolm Pirnie. 2010. Final Addendum to Site Inspection Report, Aberdeen Proving Ground,
Maryland. January.

MDE. 2010. Facts About...Swann Park. Updated 21 May 2010. Available at:
https://mde.maryland.gov/programs/ResearchCenter/ReportsandPublications/Documents/ww
w.mde. state. md.us/assets/document/Swann_Park_Fact_Sheet_05_21.pdf.

MDNR. 2002. Family-Level Key to the Stream Invertebrates of Maryland and Surrounding
Areas.

National Oceanic and Atmospheric Administration. 2012. National Weather Services,

NOWData. Accessed on January 23, 2012 at
http://www.nws. noaa.gov/climate/xmacis. php?wfo=lwx.

Office of Management and Budget. 2016. Circular A-94 Appendix C, November 2016, Real
Interest Rates on Treasury Notes and Bond of Specified Maturities (in percent), 30-Year.
Retrieved from https://obamawhitehouse.archives.gov/omb/circulars_a094

URS Corporation. 2007. Stakeholder Final Historical Records Review, Aberdeen Proving
Ground, Maryland. July.

U.S. Army. 2022. Proposed Plan for Aberdeen Proving Ground - Aberdeen Area Munition
Response Sites, Aberdeen, Maryland. Final. March.

U.S. Census. 2021. U.S. Census Bureau Quick Facts available at:
https://www.census.gov/quickfacts/fact/table/US/PST045221.

U.S. Environmental Protection Agency (USEPA). 1999. A Guide to Preparing Superfund
Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents.
EPA 540-R-98-031. July.

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USEPA. 2006. Munitions and Explosives of Concern Hazard Assessment Guidance, Public
Review Draft, V4. November.

USEPA. 2008a. Interim Munitions and Explosives of Concern Hazard Assessment
Methodology. USEPA Publication No. 505B08001. October.

USEPA. 2008b. Green Remediation: Incorporating Sustainable Environmental Practices into
Remediation of Contaminated Sites. EPA 542-R-08-002. Office of Solid Waste and
Emergency Response. April.

USEPA. 2011. Toolkit for Preparing CERCLA Records of Decision. OSWER 9355.6-10.
September.

USEPA. 2012. Methodology for Understanding and Reducing a Project's Environmental
Footprint. EPA 542-R-12-002. Office of Solid Waste and Emergency Response. February.

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Aberdeen Proving Ground

Military Munitions Response Program
Record of Decision


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Appendix A
MDE Letters of Concurrence

(To be provided in Final Document)


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Appendix B
Affidavits for Public Notice


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U.S. ARMY INVITES PUBLIC COMMENT
ON PROPOSED PLAN FOR THE
ABERDEEN AREA MUNITIONS RESPONSE SITES
ABERDEEN PROVING GROUND

The U.S. Army at Aberdeen Proving Ground (APG) invites the public to comment on its
Proposed Plan for the Aberdeen Area Munitions Response Sites.

PROPOSED PLAN
The Proposed Flan is available for review at
http://bit.1v/:VA-MMRP-PP. A comment
card and link for submission of written
comments is presented in the Proposed Plan.

VIRTUAL PUBLIC MEETING
APG invites the public to attend a meeting on;

DATE: 31 March 2021

TIME: 7:00 p.m.

PLACE: Please email Katrina Harris at
kharris (/bridaeconsultingcorn.com for
information on how to participate via
computer or phone.

WRITTEN COMMENTS
The 30-day public comment period on the
proposed action extends from 21 March to
20 April 2022. Written comments, post-
marked by 20 April 2022. should be sent to:
Mr. Rurik Loder
Directorate of Public Works
Environments 1 Di vis ion
Building 4304. 650 Rodman Road
Aberdeen Proving Ground. MI) 21005: or

Ms. Andrea Bar bier i, Remedial Project
Manager
USF.PA. Region Til
1650 Arch Street
Philadelphia. PA 19103-2029; or

Mr. Russell Ashley, P.G.
Maryland Department of the
Environment
Federal Facilities Section Installation

Restoration Program
1800 Washington Boulev ard. Suite 625
Baltimore. MD 21230-1719

PROPOSED ACTION—

APG has prepared a IVoposed Plan to address three Munitions Response Sites in the Aberdeen
Area of .Aberdeen Proving Ground. These sites include the Multi-Purpose Range. Former
Detonation Area, and the Gas Identification and Detonation Area. These sites were used for
various training activities during the 1.940's to mid 1950's and the sites were investigated
through several inspections and assessments from 2006 until a final Remedial Investigation
(RI) Report in 2014.

Geophysics, environmental sampling, intrusive investigations, and human and ecological risk
evaluations were performed during the RI. There are no unacceptable human health or
ecological impacts to soil sediment, surface water, or groundwater from the historical site use
and the potential for exposure to munitions and explosiv e of concern is low.

Alternatives that were evaluated in a Feasibility Study (l'S) to address the potential for
exposure to munitions included No .Action and I.and Use Controls. Land I'se Controls
include prohibiting residential use. safety through the Excavation Permit Program, and

Educational Outreach. As presented in the IYoposed Plan, the Sites warrant Land Use
Controls at the Multi-Purpose Range and Former Demolition Area Sites, and No Action at the
Gas Identification and Detonation Area based on the results of the RI l'S and risk assessments.


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Appendix C
Cost Summary


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APG-AA, Former Demolition Area MRS

Alternative 2



COST ESTIMATE SUMMARY I

Land Use Controls







ISite: Former Demolition Area (FDA) MRS



Location: APG-AA







Phase: Feasibility Study







Base Year: 2016







Capital Costs











UNIT



Description

QTY

UNIT COST TOTAL

NOTES

Public Meeting, LUCIP, APP

1

LS $ 2,079 $

2,079 See cost worksheet

Project Contingency

25%

$

520

Program Management

15%

$

312





TOTAL CAPITAL COST $

2,911

I Annual Operation and Maintenance (O&M) Costs









UNIT



Description

QTY

UNIT COST TOTAL

NOTES

Annual Sign Maintenance

60

EA $ 250 $

15,000 Replace avg of 2 signs per year

LUC Inspections

30

EA $ 377 $

11,295 See cost worksheet

Annual Memo Report

30

EA $ 550 $

16,493 See cost worksh eet





TOTAL ANNUAL COST $

42,788

Periodic Costs











UNIT



Description

QTY

UNIT COST TOTAL

NOTES

Five Year Review

6

EA $ 1,193 $

7,155 Update every 5 years for 30 years





TOTAL PERIODIC COST $

7,155



TOTAL 30-YEAR O&M COST (2% discount): ( $

42,661 |



Total Present Worth Cost (2% discount):) $

45,572 |


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APG-AA, Former Demolition Area MRS

Alternative 2





COST WORKSHEET I

Land Use Controls













(Site: Former Demolition Area (FDA) MRS











Location: APG-AA













Phase: Feasibility Study













Base Year: 2016













Cost Analysis













Description





UNIT









QTY UNIT

COST

TOTAL



NOTES

Public Meeting, LUCIP, APP













PM

1

HR

$ 100

$

100

Planning Documents for Site Inspections

Senior Engineer

6

HR

$ 93

$

558

Assume one document for APG-AA so

Junior Scientist

15

HR

$ 68

$

1,014

only a portion of the costs are included

SUXOS

2

HR

$ 80

$

170

for this MRS.

Word Processor

5

HR

$ 48

$

238









TOTAL

$

2,079



LUC Inspections













Truck

0.25

Day

$ 175

$

44

Assume field work for all APG-AA and APG-EA

Fuel/Maintenance

1

gallon

$ 2

$

2

MRSs is performed concurrently, providing

Analog metal detector

0.25

Day

$ 18

$

5

efficiencies

Trimble GPS

0.25

Day

$ 55

$

14



Geologist

1.5

HR

$ 135

$

203



UXOSO/QCS

1

HR

$ 110

$

110

Health and Safety/GC







TOTAL

$

377



Annual Memo Report













PM

0.5

HR

$ 100

$

50

Assume one document for APG-AA

Senior Engineer

1.5

HR

$ 93

$

140

so only a portion ofthe costs are

Junior Scientist

4

HR

00
<0

$

270

included for this MRS.

SUXOS

0.5

HR

$ 85

$

42



Word Processor

1

HR

$ 48

$

48









TOTAL

$

550



5-year Review













PM

1

HR

$ 100

$

100

Assume one document for APG-AA

Senior Engineer

4

HR

$ 93

$

372

so only a portion ofthe costs are

Junior Scientist

8

HR

$ 88

$

541

included for this MRS.

SUXOS

1

HR

$ 85

$

85



Word Processor

2

HR

$ 48

$

95









TOTAL

$

1,193




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APG-AA, Multi-Purpose Range MRS

Alternative 2
Land Use Controls

PRESENT WORTH SUMMARY

Site:	Multi-Purpose Range (MPR) MRS

Location:	APG-AA

Phase:	Feasibility Study

Base Year:	2016

Present Value Analysis

Annual Percentage Rate

YR

Capital

2%

Periodic
Cost

Total Costs

Present Worth

oaM

Annual

0

$2,911



-

-

$2,911

$2,911

1

-

$1

426

-

$1,426

$1,398

2

-

$1

426

-

$1,426

$1,385

3

-

$1

426

-

$1,426

$1,371

4

-

$1

426

-

$1,426

$1,358

5

-

$1

426

$ 1,193

$2,619

$2,469

6

-

$1

426

-

$1,426

$1,332

7

-

$1

426

-

$1,426

$1,319

8

-

$1

426

-

$1,426

$1,306

9

-

$1

426

-

$1,426

$1,294

10

-

$1

426

$ 1,193

$2,619

$2,352

11

-

$1

426

-

$1,426

$1,269

12

-

$1

426

-

$1,426

$1,257

13

-

$1

426

-

$1,426

$1,245

14

-

$1

426

-

$1,426

$1,233

15

-

$1

426

$ 1,193

$2,619

$2,243

16

-

$1

426

-

$1,426

$1,210

17

-

$1

426

-

$1,426

$1,199

18

-

$1

426

-

$1,426

$1,188

19

-

$1

426

-

$1,426

$1,177

20

-

$1

426

$ 1,193

$2,619

$2,141

21

-

$1

426

-

$1,426

$1,155

22

-

$1

426

-

$1,426

$1,145

23

-

$1

426

-

$1,426

$1,134

24

-

$1

426

-

$1,426

$1,124

25

-

$1

426

$ 1,193

$2,619

$2,045

26

-

$1

426

-

$1,426

$1,104

27

-

$1

426

-

$1,426

$1,094

28

-

$1

426

-

$1,426

$1,084

29

-

$1

426

-

$1,426

$1,074

30

-

$1

426

$ 1,193

$2,619

$1,955

TOTALS

$2,911

$42,788

$7,155

$52,855

$45,572


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Appendix D
Summary of Comments Received During
Public Comment Period and Army Responses


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Directorate of Public Works - Aberdeen Proving Ground

1. Version: 1.0

Project:

Aberdeen Proving Ground - Aberdeen Area (APG-AA)

Document:

Proposed Plan for Aberdeen Proving Ground, Aberdeen Area Munitions Response Sites, March 2022

Contract:

W91ZLK-13-D-0002

Reviewer:

MDE RPM, Russell Ashley, P.G.

Section:

Federal Facilities Installation Restoration Program

Date:

4/15/22

Response By:



Affiliation:



Date:



Item

Reference

Comment

Contractor Response

Action

MDE RPM, Russell Ashley, P.G.; comment received 15 April 2022

1

General

Maryland Department of the Environment Cleanup
Standards for Soil and Groundwater references
The Maryland Department of the Environment's "Cleanup
Standards for Soil and Groundwater" (2018) were
specifically developed to support the Voluntary Cleanup
Program as well as other programs within the Maryland
Department of the Environment for use in lieu of and/or in
support of a site specific risk assessment. The guidance
specifically states on Page 3 which State programs for
which the guidance was intended. The guidance was not
intended for use at sites complying with the federal
Comprehensive Environmental Response, Compensation,
and Liability Act (CERCLA).

The Maryland Cleanup Standards for Soil and Groundwater
establish a cancer risk of lxl0"6 and a hazard quotient of
0.1, similar to screening levels for soil and groundwater at
CERCLA sites. However, the Maryland Cleanup Standards
for Soil and Groundwater were most recently updated in
October 2018, whereas the Regional Screening Level
(RSL) tables prepared by the United States Environmental
Protection Agency (https://www.epa.gov/risk/regional-
screening-levels-rsls) are updated on a much more regular
basis (typically once or twice per year). Therefore, please
remove all reference and use of the Maryland Department
of the Environment's "Cleanup Standards for Soil and
Groundwater" from this and future documents, and instead
reference the more frequently updated RSL tables.

The Proposed Plan mentions the MDE Cleanup
Standards when summarizing the findings of
historical investigations because the Cleanup
Standards are comparison values used in those
investigations. The historical investigations,
particularly the human health risk assessments,
also used USEPA RSLs. Because the Proposed
Plan is summarizing historical documents and
the comparison values used in the historical
documents, no changes to the PP will be made.

None


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