PB98-964502
EPA 541-R98-028
October 1998
EPA Superfund
Record of Decision:
Yuma Marine Corps Air Station
OU2
Yuma, AZ
12/2/1997
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Final
Record of Decision for Operable Unit 2
Marine Corps Air Station
Yuma, Arizona
t
YUMA ARIZONA
August 29,1997
Prepared for
Southwest Division
Naval Facilities Engineering Command
San Diego, California
Prepared by
Uribe & Associates
220 California Avenue
Palo Alto, CA 94306
(415) 325-9195
ContractN68711-94-D-1611, Delivery OrderB
U&A Project 180-06
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Final
Record of Decision for Operable Unit 2
Marine Corps Air Station
Yuma, Arizona
YUMA ARIZONA
August 29,1997
I
Prepared for
Southwest Division
Naval Facilities Engineering Command
San Diego, California
Prepared by
Urlbe & Associates
220 California Avenue
Palo Alto, CA 94306
(415) 325-8195
Contract N68711-94-D-1611, Delivery Order 6
U&A Project 180-06
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Draft Final Record of Decision for Operable Unit 2
Marine Corps Air Station
Yuma, Arizona
Contents
Section Page
1 Declaration 1-1
1.1 Introduction 1-1
1.2 Site Name and Location 1-1
1.3 Statement of Basis and Purpose 1-2
1.4 Assessment of the Site 1-2
1.5 Description of the Selected Remedy 1-3
1.6 Statutory Determinations 1-7
2 Decision Summary 2-1
2.1 Introduction 2-1
2.2 MCAS Yuma Site Location and Description 2-2
2.3 MCAS Yuma Installation Operational History 2-3
2.4 Enforcement and Regulatory History 2-3
2.5 Operable Unit 2 Site Selection History 2-4
2.6 Operable Unit 2 Site Descriptions 2-6
2.6.1 Introduction 2-6
2.6.2 CAOC 1: Flight Line 2-6
2.6.3 CAOC 2: Shop Areas 2-7
2.6.4 CAOC 3: Auto Hobby Shop 2-7
2.6.5 CAOC 4: Radar Hill Disposal Area 2-8
2.6.6 CAOC 5: Old 2nd LAAMBN Compound 2-8
2.6.7 CAOC 6: First Sewage Lagoon 2-9
2.6.8 CAOC 7: Fire School Area 2-9
2.6.9 CAOC 8: Southeast Station Landfill 2-10
2.6.10 CAOC 9: Southeast Sewage Lagoon 2-11
2.6.11 CAOC 10: Ordnance Munitions Disposal Area 2-11
2.6.12 CAOC 11: Radiation Disposal Pipes 2-12
2.6.13 CAOC 12: Tear Gas Burial Area 2-13
2.6.14 CAOC 13: Drain Field Area 2-13
2.6.15 CAOC 14: Drain Field South of Building 97 2-13
2.6.16 CAOC 15: Hazardous Waste USTs 363 and 364 2-14
2.6.17 CAOC 16: Hazardous Waste USTs, Building 230-2 and 230-4 2-14
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Draft Final Record of Decision for Operable Unit 2
Marine Corps Air Station
Yuma, Arizona
Contents
Section Page
2.6.18 CAOC 17: Hazardous Waste Underground Storage Tank 1708-3 2-14
2.6.19 CAOC 18: Old Drum Storage Area 2-15
2.7 Highlights of Community Participation 2-15
2.8 Scope and Role of Operable Unit 2 .....2-16
2.9 Summary of Field Investigation 2-17
2.10 Summary of Risk Assessment 2-18
2.10.1 Human Health Risk Assessment 2-18
2.10.2 Identification of COPCs : 2-18
2.10.3 Exposure Assessment 2-20
2.10.4 Toxicity Assessment 2-21
2.10.5 Development of Risk-Based Criteria 2-22
2.10.6 Summary of Risks at Individual CAOCs : 2-23
2.11 Summary of Ecological Risks 2-26
2.12 Description of Alternatives 2-27
2.12.1 Introduction 2-27
2.12.2 CAOCs Requiring Remediation of ACM in Soil 2-27
2.12.3 Alternatives Considered for Remediating CAOCs 4, 7, and 9 2-28
2.12.4 CAOCs with Potential Health Risks 2-30
2.12.5 Alternatives Considered for Responding to Potential Health Risks at
CAOCs 1,8A, and 10 f 2-30
2.13 Summary of the Comparative Analysis of Alternatives 2-32
2.13.1 Introduction 2-32
2.13.2 Applicable or Relevant and Appropriate Requirements 2-33
2.13.3 Preferred Alternative for ACM in Soil 2-34
2.13.4 Preferred Alternative for Responding to Potential Health Risks at
CAOCs 1,8A and 10 : 2-39
2.14 The Selected Remedies 2-42
2.14.1 Selected Remedy for ACM in Soils 2-42
2.14.2 Selected Remedy for Potential Health Risks at CAOCs 1,
8A,andlO 2-43
2.15 Statutory Determinations 2-45
2.15.1 Introduction 2-45
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Draft Final Record of Decision for Operable Unit 2
Marine Corps Air Station
Yuma, Arizona
Contents
Section Page
2.15.2 Statutory Determinations for Selected Remedy for ACM in Soils 2-45
2.15.3 Statutory Determinations for Selected Remedy for Potential
Health Risks at CAOCs 1,8A, and 10 2-50
2.16 Documentation of Significant Changes 2-53
3 Responsiveness Summary 3-1
3.1 Overview 3-1
3.2 Background on Community Involvement 3-1
3.3 Summary of Comments Received During Public Comment Period and
Department of the Navy Responses 3-2
4 References 4-1
5 Abbreviations /Acronyms 5-1
9
Appendices
A Response to U.S. Environmental Protection Agency and Arizona Department
of Environmental Quality Comments on the Draft Record of Decision for
Operable Unit 2, Marine Corps Air Station, Yuma, Arizona
B Community Relations Activities Conducted by Navy
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Draft Final Record of Decision for Operable Unit 2
Marine Corps Air Station, Yuma Arizona
Contents
Table
2-1 Chemicals of Potential Concern (COPC) for OU2
2-2 Maximum Concentrations of Volatile Organic Compounds Detected as
COPCs at 0 to 10 Feet
2-3 Maximum Concentrations of Semi-Volatile Organic Compounds and Total
Petroleum Hydrocarbons Detected as COPCs
2-4 Maximum Concentrations of Pesticides and PCBs Detected as COPCs
at 0 to 10 Feet
2-5 Maximum Detected Values and Background Threshold Limit Values (TLV)
for Metals Detected at 0 to 10 Feet
2-6 ARARs for Remediation of Asbestos-Contaminated Soil at MCAS Yuma
2-7 ARARs for Potential Health Risks at MCAS Yuma
2-8 Human Health Based Guidance Levels (HBGLs) for Ingestion of
Contaminants in Soil at CAOC 1,8A, and 10
2-9 Alternative 3, Soil Volume Estimates
2-10 Cost Estimate for Alternative 3: Cleanup of ACM on Soil Surface and
Excavation and Disposal of Soil Mixed with ACM
2-11 Cost Estimate for Cleanup of ACM on Soil Surface
2-12 Potential ARARs for Remedial Action for MCAS Yuma
Figure
1-1 Location Map for MCAS Yuma
1-2 Location of CAOCs in OU2
2-1 CAOC 1: Feature and Boring Location Map
2-2 CAOC 1: Total PAH Concentration Contours for Surface Samples, Southern Detail
2-3 CAOC 1: Total PAH Concentration Contours for Surface Samples, Northern Detail
2-4 CAOC 4: Location of ACM and ACM-Contaminated Soil
2-5 CAOC 7: Location of Subunit 7A
2-6 CAOC 7: Location of Subunit 7B
2-7 CAOC 8: Feature and Boring Location Map
2-8 CAOC 9: Location of ACM Debris
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Draft Final Record of Decision for Operable Unit 2
Marine Corps Air Station, Yuma Arizona
Contents
Figure
2-9 CAOC 10: Feature Map
2-10 CAOC 10: PAH Sampling Locations with Total PAH Concentrations
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1 Declaration
1.1 Introduction
This Record of Decision (ROD) for Operable Unit (OU2) documents the remedial
action plan for OU2 at Marine Corps Air Station (MCAS), Yuma, Arizona. This
ROD was prepared by Uribe & Associates (U&A) for Southwest Division Naval
Facilities Engineering Command (Southwest Division) under Contract N68711-94-
D-1611, Delivery Order 6.
1.2 Site Name and Location
The Marine Corps Air Station (MCAS), covering approximately 3,000 acres, is
located in the City and County of Yuma, Arizona (Figure 1-1). Marine Corps Air
Station Yuma (Station) was declared a permanent Air Force installation in 1954.
In January 1959, the Station and its associated range facilities were transferred to
the U.S. Navy. The Station currently operates the airport facility as a joint
military/civilian airport. MCAS Yuma is located on the northern portion of Yuma
Mesa, approximately 60 to 70 feet above and four miles from the Colorado River.
The City of Yuma, the nearest municipality, is located approximately one mile
northwest of the Station.
The final Federal Facility Agreement (FFA) was signed in January, 1992, by the
U.S. Environmental Protection Agency (U.S. EPA), the Department of the Navy
(Navy), and the Arizona Department of Environmental Quality (ADEQ) to
establish a framework and schedule for implementing environmental
investigations and appropriate remedial actions under the Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA). Two
Operable Units (OUs) were established under the auspices of the FFA. OU2
includes surface disposal units and contamination shallower than ten feet below
ground surface. The OU2 Remedial Investigation included the following
CERCLA areas of concern (CAOCs), as shown on Figure 1-2:
CAOC 1, Flight Line
CAOC 2, Shops Area
CAOC 3, Auto Hobby Shop
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CAOC 4, Radar Hill Disposal Area
CAOC 5, Old 2nd LAAMBN Compound
CAOC 6, First Sewage Lagoon
CAOC 7, Fire School Area
CAOC 8, Southeast Station Landfill
CAOC 9, Southeast Sewage Lagoon
CAOC 10, Ordnance Munitions Disposal Area
CAOC 11, Radiation Disposal Pile
CAOC 12, Tear Gas Burial Area
CAOC 13, Drain Field Area
CAOC 14, Lagoon South of Building 97
CAOC 15, Hazardous Waste USTs. 363 and 364
CAOC 16, Hazardous Waste USTs, Building 230-2 and 230-4
CAOC 17, Hazardous Waste Underground Storage Tank 1708-3
CAOC 18, Old Drum Storage Area
1.3 Statement of Basis and Purpose
This ROD presents a response action for OU2, which consists of 18 CAOCs that
were identified as possible locations of soil contamination from past activities at
MCAS Yuma. These areas were selected in accordance with CERCLA as amended
by the Superfund Amendments and Reauthorization Act (SARA) of 1986 and to
the extent practicable, the National Contingency Plan (NCP). This ROD explains
the basis for selecting the response action for the 18 CAOCs comprising OU2.
Information supporting the selected response action is contained in the
Administrative Record for MCAS Yuma. The U.S. EPA, Navy, and ADEQ concur
with the selected response actions.
1.4 Assessment of the Site
A Remedial Investigation (RI) for OU2 was performed by Jacobs Engineering
Group (JEG, 1996). As part of the RI, a human health and ecological risk
assessment was performed for each of the 18 CAOCs to assess the potential
impacts of hazardous substances on human health, the environment, and
groundwater quality (JEG, 1995b). Based on the RI, U.S. EPA, ADEQ, and the
Navy agreed that 12 of the CAOCs require no further action. Six of the CAOCs
require action:
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CAOCs 4, 7, and 9: Asbestos-containing building materials have been
identified in construction debris and have the potential to release asbestos
fibers into the environment.
CAOCs 1 and 10: The human health risk assessment indicated that residential
use of these CAOCs had a potential to present an unacceptable level of
carcinogenic risk.
CAOC 8A: Intrusive sampling was not conducted at the southeast station
landfill during the RI because of potential drilling hazards (Section 2.6.9).
Based on the human health risk assessment, it was concluded that a landfill
cap was not required under the current land use. However, since the interior
of the landfill was not investigated during the RI, the risk from exposure to the
landfill interior is unknown.
A Feasibility Study (FS) was conducted to evaluate remedial alternatives for the
six CAOCs. For CAOCs 4, 7, and 9, where surface disposal of asbestos waste was
confirmed, the FS developed a remedial approach that minimizes potential health
threats and allows unrestricted use of the CAOCs. Asbestos can affect human
health if left unmanaged. Asbestos-containing material in these three areas
presents a substantial threat of release, which may pose a significant risk to
human health and the environment if not addressed by implementing the
response action selected in this ROD. This ROD describes the rationale for
selecting the alternative to cleanup ACM contamination at the three CAOCs.
For CAOCs 1, 8A, and 10 the health risk assessment indicated that potential health
risks were within acceptable levels under current land use, but could become
unacceptable if land use changed. The FS evaluated institutional controls to
protect human health.
1.5 Description of the Selected Remedy
On the basis of the data collected at the OU2 sites, no further action is necessary
for 12 of the 18 CAOCs included in OU2, because these sites do not pose a threat
to human health or the environment. However, remedial action is required to
protect human health and comply with regulatory requirements at three of the
CAOCs in OU2 because of the presence of ACM. In addition, institutional
controls will be implemented to minimize potential health risks that might be
associated with land use changes in CAOC 1, 8A, and 10.
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Selected Remedy for ACM
Four alternatives have been developed and evaluated for the remediation of ACM
at MCAS Yuma. The alternatives were based on the nine criteria established by
U.S. EPA, listed below:
Overall Protection of Human Health and the Environment
Compliance with ARARs
Long-Term Effectiveness and Permanence
Reduction of Toxicity, Mobility, or Volume
Short-Term Effectiveness
Implementability
Cost
State Acceptance
Public Acceptance
The four alternatives evaluated are listed and briefly described below:
Alternative 1No Action
The No-Action alternative was used as a baseline alternative Against which other
alternatives were judged. With this alternative, there would be no action to treat,
contain, or remove any of the surface ACM or ACM-contaminated soil.
Alternative 2Cleanup of Surface ACM Debris
Under this alternative, ACM fragments visible on soil surfaces would be collected
manually. Collection would include removing approximately the upper inch of
soil beneath the ACM to reduce the potential for asbestos fibers remaining behind
in the soil. The ACM and soils would be stockpiled, manifested, loaded,
transported, and disposed of at a permitted facility.
Alternative 3Cleanup of ACM on Soil Surface and Excavation of Soils Mixed
with ACM
Under this alternative, ACM fragments visible on soil surfaces would be collected
manually, as described under Alternative 2. In areas in which ACM is mixed with
soil beneath the surface (CAOC 4A, north of Building 38; and CAOC 7A, limited
area near the active bum pit), the contaminated soils would be excavated with
conventional construction equipment.
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Alternative 4Cleanup of ACM on Soil Surface, Partial Excavation, and Partial
Capping
Under this alternative, ACM fragments visible on soil surfaces would be collected
manually, as described under Alternative 2. In the limited area near the active
burn pit (CAOC 7A), where ACM is mixed with surface soils to a maximum depth
of one foot, the contaminated soils would be excavated with conventional
construction equipment, as in Alternative 3. This alternative differs from
Alternative 3 in that only the central portion of the remedial unit north of Building
38 (CAOC 4A) would be excavated, since the Station has plans to develop this
area. The eastern portion of CAOC 4A would be capped with asphalt.
The selected alternative for addressing asbestos at MCAS Yuma is Alternative 3,
cleanup of ACM on soil surface and excavation of soils mixed with ACM. This
alternative meets the nine ranking criteria that the U.S. EPA uses to evaluate
alternatives.
Selected Remedy for Potential Health Risks
Two alternatives were developed and evaluated to address potential health
threats identified by the human health risk assessment for CAOC 1 and CAOC 10
and the potential health threat associated with land use changes at CAOC 8A.
These alternatives were based on the nine criteria listed above in the discussion of
alternatives for ACM. The alternatives are listed and briefly described below.
Alternative 1No Action
This alternative does not reduce the potential risk to human health and is unlikely
to be accepted by the state or the community.
Alternative 2Institutional Controls
Institutional controls would restrict the land use of CAOC 1 and CAOC 10 to
industrial/commercial use and CAOC 8A to the current use (inactive
landfill/surface disposal area). The institutional controls would be implemented
through the MCAS Yuma Base Master Plan (BMP), which would reference the
OU2 ROD. Additions to the BMP would include a map indicating the locations of
the former disposal areas in CAOC 8A. This would include execution and
recordation of a VEMUR in accordance with and substantially in the form set out
at Arizona Revised Statutes, Section 49-152. The VEMUR would contain language
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clarifying that it was executed and recorded by the federal government, or the
appropriate entity of the federal government, "for itself only, and not as a
covenant running with the land". In addition, it would clarify that:
a. The parties agree that no interest in real property on behalf of the State of
Arizona is created either by this VEMUR or by any notice of cancellation
of this VEMUR pursuant to A.R.S. 49-152.
b. The signature of an authorized representative of the Arizona Department
of Environmental Quality (ADEQ) which appears herein acknowledges
that the remediation of the property was conducted in accordance with
the provisions of A.R.S 49-152.
The MCAS Yuma Base Master Plan would require that any changes in activities or
land use in these CAOCs be coordinated through and reviewed by the MCAS
Yuma Environmental Department. Before the land use restrictions are
incorporated in the BMP, the Navy will obtain the approval of the U.S. EPA for
the language of the restrictions and the location in the BMP at which the approved
language will be incorporated. In the event that the Navy plans any future
changes in land use at CAOCs 1, 8A, or 10, the Navy in consultation with U.S.
EPA and ADEQ would re-evaluate the remedy in light of the intended land use.
If the change in land use is not compatible with the remedy, the remedy may be
changed pursuant to CERCLA Sections 120 and 121 and the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP) Section 300.430(f)(4)(iii)
and the ROD may be amended. If the Navy plans to excess the property to a non-
federal entity, it will notify ADEQ and EPA in advance of the execution of any
such transfer. The Navy will consult with ADEQ and EPA in revisiting existing
land use classifications/restrictions for the CAOC (or, in the alternative, the
remedial action selection) to determine if the foreseeable future land use differs
from the assumptions made at the time the original remedial action decision was
made. At that time, a re-evaluation of the appropriate institutional controls will
be undertaken by the Navy, in consultation with ADEQ and EPA.
For CAOC 1 and CAOC 10, a change in land use from industrial to residential use
would require re-evaluation of the remedy. For CAOC 8A, a change in land use
involving any activities that may disrupt and expose the landfill interior would
require re-evaluation of the remedy. At the time of these future activities, further
investigation may be undertaken in order to determine if remediation is required
and if the ROD must be amended.
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The selected alternative for addressing potential health risks at CAOCs 1, 8A, and 10
is Alternative 2, institutional controls. This alternative meets the nine ranking criteria
that the U.S. EPA uses to evaluate alternatives.
1.6 Statutory Determinations
No response action is necessary to protect human health or the environment at 12 of
the 18 CAOCs within the OU2 site. This "no further action" alternative was selected
because no contaminants found at 12 of the CAOCs were present at concentrations
that pose an unacceptable risk to human health or the environment based on U.S. EPA
risk guidelines. The "no further action" alternative is protective of human health and
the environment and complies with federal and State of Arizona requirements that
are legally applicable or relevant and appropriate to the remedial action. This action
is a permanent solution to the maximum extent practicable or necessary for these
CAOCs. Because this action will not result in hazardous substances remaining on site
exceeding unacceptable health-based levels, the five-year review will not apply to this
action.
Asbestos-containing materials (ACM) are to be removed from three CAOCs. The
rationale for selecting Alternative 3 as the preferred alternative for the remediation of
ACM at CAOCs 4, 7, and 9, was based on the U.S. EPA criteria listed in Section 1.5.
Alternative 3 is protective of human health and the environment, complies with the
State of Arizona and federal requirements that are legally applicable or relevant and
appropriate to the remedial action, is cost effective, and would be a permanent
solution to the maximum extent practical or necessary for OU2. Because Alternative 3
will not result in hazardous substances remaining on site exceeding acceptable health-
based levels, the five-year review will not apply to this action.
The asbestos-containing material (ACM) to be removed from CAOCs 4, 7, and 9
includes transite siding, transite pipe, cement pipe, roofing materials, vinyl,
fiberboard and floor tile mastic. This ACM is "nonfriable" which means that it cannot
be crumbled, pulverized, or reduced to powder by hand pressure when dry (40 CFR
Section 61.141). Nonfriable ACM is a CERCLA hazardous substance, but not a RCRA
hazardous waste. See 40 CFR, Section 302.4 (CERCLA) and 40 CFR, Part 261 (RCRA).
Since the ACM is a CERCLA hazardous substance. Alternative 3 must be conducted
in a way that complies with U.S. EPA's Off-Site Policy (40 CFR Section 300.440).
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The institutional controls will restrict the land use of CAOC 1 and CAOC 10 to
industrial/commercial use and CAOC 8A to the current use (inactive landfill /surface
disposal area). The institutional controls will be implemented through the Base
Master Plan, which will reference the OU2 ROD. Additions to the Base Master Plan
will include a map indicating the locations of the former disposal areas in CAOC 8A.
This would include execution and recordation of a VEMUR in accordance with and
substantially in the form set out at Arizona Revised Statutes, Section 49-152. The
VEMUR would contain language clarifying that it was executed and recorded by the
federal government, or the appropriate entity of the federal government, "for itself
only, and not as a covenant running with the land". In addition, it would clarify that:
a. The parties agree that no interest in real property on behalf of the State of
Arizona is created either by this VEMUR or by any notice of cancellation of
this VEMUR pursuant to A.R.S. 49-152.
b. The signature of an authorized representative of the Arizona Department of
Environmental Quality (ADEQ) which appears herein acknowledges that the
remediation of the property was conducted in accordance with the provisions
of A.R.S 49-152.
The Base Master Plan will require that any changes in activities or land use in these
*
CAOCs be coordinated through and reviewed by the MCAS Yuma Environmental
Department. Before the land use restrictions are incorporated in the BMP, the Navy
will obtain the approval of the U.S. EPA for the language of the restrictions and the
location in the BMP at which the approved language will be incorporated. In the
event that the Navy plans any future changes in land use at CAOCs 1, 8A, or 10, the
Navy in consultation with U.S. EPA and ADEQ would re-evaluate the remedy in light
of the intended land use. If the Navy plans to excess the property to a non-federal
entity, it will notify ADEQ and EPA in advance of the execution of any such transfer.
The Navy will consult with ADEQ and EPA in revisiting existing land use
classifications/restrictions for the CAOC (or, in the alternative, the remedial action
selection) to determine if the foreseeable future land use differs from the assumptions
made at the time the original remedial action decision was made. At that time, a re-
evaluation of the appropriate institutional controls will be undertaken by the Navy, in
consultation with ADEQ and EPA.
The rationale for selecting Alternative 2 as the preferred alternative for potential
health risks at CAOCs 1, 8A, and 10 was based on the U.S. EPA criteria listed in
Section 1.5. Alternative 2 will be protective of human health and the environment,
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comply with the State of Arizona and federal requirements that are legally applicable
or relevant and appropriate to the remedial action, and be cost effective. Because
Alternative 2 will result in hazardous substances remaining on site, a five-year review
will apply to this action.
Colonel C/f. Turner
Commanding Officer
MCAS Yuma
Daniel D. Opalski
Chief
Federal Facilities Cleanup Branch
U.S. EPA, Region 9
Russell F. Rhoades
Director
Arizona Department of Environmental Quality
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2 Decision Summary
2.1 Introduction
This section provides an overview of the site-specific factors and analysis that led
to the selection of the "no further action" decision for 12 of the 18 CAOCs in OU2,
the selection of the preferred alternative for the clean-up of ACM at three of the
CAOCs, and the implementation of institutional controls to minimize potential
health risks that might be associated with land use changes at three of the CAOCs.
The overview includes the following descriptions, histories, summaries, and
conclusions:
A general description of MCAS Yuma location and regional setting.
A brief history of past operations at MCAS Yuma.
A brief history of regulatory and enforcement actions for OU2.
A brief summary of reasons for including specific CAOCs in OU2.
A summary of characteristics for each CAOC within OU2.
*
A summary of target analytes that were considered constituents of potential
concern (COPCs) at the CAOCs during the remedial investigation of OU2.
A summary of the human health risk and ecological risk assessments for the
CAOCs within OU2.
A summary of the selection of "no further action" based on the risk
assessment for 12 of the CAOCs within OU2 and the selected remedy for six
CAOCs requiring remedial action.
A description of significant changes to the selected remedy.
These reports are included in the Administrative Record for MCAS Yuma. Much
of the information presented in this overview was derived from previous
assessments and investigations performed by Southwest Division, Naval Facilities
Engineering Command (Navy) and its contractors. Results and conclusions of
these assessments and investigations are presented in greater detail in the Initial
Assessment Study (Stearns et al, 1985), Confirmation Study Verification Phase
(Malcolm Pirnie, 1988), Site Inspection (Malcolm Pimie, 1990), Asbestos Survey
Results (Jacobs Engineering Group, Inc. [JEG], 1995a), Final Remedial
Investigation Report QEG, 1996), Assessment of ACM Contamination (U&A,
1996a), Feasibility Study (U&A, 1996b), and Proposed Plan (U&A, 1996c).
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2.2 MCAS Yuma Site Location and Description
MCAS Yuma is located in a desert environment, with mild winters and hot
summers. The total annual precipitation in the Yuma area is approximately two to
three inches with total potential evapotranspiration exceeding 50 inches (JEG,
1996). MCAS Yuma has installed 51 dry wells that receive storm water from
precipitation events and allow the storm water to infiltrate into the ground.
Precipitation events generate small areas of ponded water on the base, but
significant quantities of surface water runoff are not generated by precipitation
events. Winds are usually light (0 to 6 miles per hour [mph]) to moderate (6 to 16
mph), with an average relative humidity of 20 percent.
The site is located on the northern portion of Yuma Mesa, approximately 60 to
70 feet above the adjacent Colorado River Valley. Sedimentary deposits on Yuma
Mesa are predominantly fluvial (river) deposits with minor eolian (windblown)
deposits in the upper 180 to 200 feet. These deposits overlie pre-Tertiary bedrock,
which crops out in a series of low hills at and around the Station. Geologic
materials encountered during previous investigations performed at MCAS Yuma
consist of fine to coarse sand with interbeds of clay, silt, and gravel. Local soils
are characterized as excessively drained sand with rapid permeability.
GroundWater in the vicinity of MCAS flows to the northwest with a gradient of 15
to 20 feet per mile. The groundwater table is typically encountered about 50 feet
below ground surface.
No natural surface drainage occurs at MCAS Yuma because of its relatively level
topography, low precipitation, and high evaporation. No large surface water
bodies are located within the immediate vicinity of MCAS Yuma. The Colorado
River, the most significant surface water feature, is located approximately four
miles north of MCAS Yuma. Local flooding occurs during storms at the Station,
especially in areas where the ground surface is covered with concrete. Minor
erosional features, such as gullies and rills, have been noticed near the
southwestern end of the runway, as a result of runoff following a storm (JEG,
1996).
Plants and animals within MCAS Yuma are characterized as desert species and
species associated with developed areas or species attracted by irrigated areas. No
state or federally listed threatened or endangered species are currently known to
be present at MCAS Yuma (JEG, 1995b).
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2.3 MCAS Yuma Installation Operational History
In early 1928, the U.S. Government leased 640 acres of desert land near the City of
Yuma to Yuma County to establish an airfield. The U.S. Bureau of Reclamation
(Bureau) leased the airfield to Yuma County to construct a small aircraft hanger
and runway in 1937. From 1941 to 1946, the facility was leased to the U.S. Army
Air Corps for pilot training and bomber crew training. Field activity ceased with
the end of World War II, and the area was returned to the control of the Bureau.
Yuma County obtained rights to use the airfield for civilian purposes from the
Bureau in 1948. In July 1951, the U.S. Air Force reactivated the station as a
Weapons Proficiency Center for fighter-interceptor units. The Station was
declared a permanent Air Force installation in 1954.
In January 1959, the Station and its associated range facilities were transferred to
the U.S. Department of the Navy. MCAS Yuma was established in 1959 to
provide services and materials support operations to the Marine Aircraft Wing
and its subordinate units. MCAS Yuma currently operates the airport facility as a
joint military/civilian airport. Since 1959, major improvements have included the
construction of a 13,300-foot runway, development of the Instrumented Special
Weapons'System, and the addition of a Tactical Air Crew Combat Training
System.
2.4 Enforcement and Regulatory History
During its 70 years of operation, the Station has generated industrial wastes such
as used oil, fuels, solvents, paint residues, battery acid, pesticides, herbicides, and
polychlorinated biphenyls (PCBs). In the early years, some of these wastes were
disposed of in landfills, burn pits, and other areas located throughout the Station.
Construction and improvement activities also generated construction debris,
which has been disposed of in undeveloped portions of the Station.
Remedial investigations were initiated in 1985 to investigate past disposal sites at
MCAS Yuma. Early studies indicated the presence of chlorinated solvents in
underlying groundwater. As a result, in 1990, MCAS Yuma was placed on the
Superfund National Priorities List (NPL). Section 120 of CERCLA requires federal
facilities to investigate and clean up past releases of hazardous waste that may
pose a risk to human health or the environment.
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Investigations performed at MCAS Yuma include the Remedial
Investigation/Feasibility Study (RI/FS) (]EG, 1996), supplemental sampling
programs at CAOC 10 (Uribe, 1996d; Uribe, 1997), Federal Facility Agreement
Assessment Program (FFAAP) (Steams, 1985), and underground storage tank
investigations (JEG, 1995b).
In 1990, shortly following MCAS Yuma's listing on the NPL list, the Navy entered
into a FFA with U.S. EPA and ADEQ to establish a framework and schedule for
implementing environmental investigations and appropriate cleanup actions. The
Final FFA was signed in January, 1992. The Navy and regulatory agencies agreed
to subdivide the Station into two Operable Units (OUs), one to address potential
areas of groundwater contamination and soil contamination deeper than 10 feet
below ground surface (OU1) and one for soil contamination shallower than 10 feet
below ground surface (OU2). OU1 will be addressed by a separate ROD
following completion of the investigative process.
The Navy is the lead agency under the NCP for conducting investigation and
remediation of MCAS Yuma pursuant to CERCLA. This process is conducted in
consultation with U.S. EPA, as the lead regulatory agency, and with ADEQ, as the
supporting state regulatory agency for these activities. There have been no
enforcement actions for OU2.
2.5 Operable Unit 2 Site Selection History
OU2 consists of surface disposal and disposal units within the upper 10 feet of soil
underlying the Station, where disposal or releases of petroleum products, paints,
solvents, metals, pesticides, and other process chemicals may have occurred.
Contamination of groundwater underlying the Station and soils greater than 10
feet below the ground surface are addressed by the Installation Restoration
Program (IRP) for OU1. The objectives of the OU2 environmental restoration
program are to evaluate the environmental condition of the CERCLA areas of
concern (CAOCs); identify threats to human health, the environment, and
groundwater quality; and develop cleanup actions to protect human health and
the environment. Based on the human health and environmental risk
assessments, the RI recommended no remedial action for 12 of the 18 CAOCs in
OU2. ACM was identified at three of the 18 CAOCs, and these CAOCs are the
only CAOCs that require remediation within OU2. In addition, institutional
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controls will be implemented for CAOCs 1, 8, and 10 to minimize potential health
risks that might be associated with land use changes at these CAOCs.
Based on the results of preliminary investigations, the RI was conducted at the
following CAOCs within OU2 at MCAS Yuma:
CAOC1, Right Line
CAOC 2, Shops Area
CAOC 3, Auto Hobby Shop
CAOC 4, Radar Hill Disposal Area
CAOC 5, Old 2nd LAAMBN Compound
CAOC 6, First Sewage Lagoon
CAOC 7, Fire School Area
CAOC 8, Southeast Station Landfill
CAOC 9, Southeast Sewage Lagoon
CAOC 10, Ordnance Munitions Disposal Area
CAOC 11, Radiation Disposal Pile
CAOC 12, Tear Gas Burial Area
CAOC 13, Drain Field Area
CAOC 14, Lagoon South of Building 97
CAOC 15, Hazardous Waste USTs 363 and 364
CAOC 16, Hazardous Waste USTs 230-2 and 230-4
CAOC 17, Hazardous Waste Underground Storage Tank 1708-3
CAOC 18, Old Drum Storage Area
The RI was conducted in 1995 and included an assessment of each CAOC. RI
activities included a surface reconnaissance and historic information search, aerial
photography review, interviews with former employees and personnel stationed
at the base, geophysical surveys (to look for buried tanks, drums, or other
underground objects that might contain hazardous substances), surface and
subsurface soil sampling, soil gas surveys (to look for hazardous substances that
might have vaporized in soils), and human health and ecological risk assessments.
The results of the RI are presented in the document titled Marine Corps Air Station,
Yuma, Arizona, Operable Unit 2, Remedial Investigation, Final Report, dated March 26,
1996, prepared by Jacobs Engineering Group, Inc. (JEG, 1996). The RI, along with
reports of previous assessments and investigations, are contained in the
Administrative Record.
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2.6 Operable Unit 2 Site Descriptions
2.6.1 Introduction
The location of the 18 CAOCs investigated under the RI are shown on Figure 1-2.
CAOC-specific figures are provided in Figures 2-1 though 2-10 for the six CAOCs
at which remedial actions are required. A brief description of the facilities, past
operations, and potential sources of contaminants is provided in the following
paragraphs. Because groundwater issues are included in the IRP for OU1, and
surface water is not present at MCAS Yuma, potential pathways for released
contaminants are limited to contact with site soils, site-derived soil dusts, or site-
derived soil vapors.
2.6.2 CAOC1: Flight Line
CAOC 1 consists of the pre-1960 flight line (runways, aprons, and taxiways) and
associated aircraft maintenance/hangar facilities (Figure 2-1). This CAOC is
located in the north-central portion of MCAS Yuma and occupies approximately
170 acres. Used oils were frequently drained from aircraft engines directly onto
the ground surface beneath parked aircraft. Used oil was also used routinely for
*
dust control around hangars, runways, taxi ways, and apron edges.
The primary finding of the field sampling and analysis program was the
widespread detection of Total Recoverable Petroleum Hydrocarbons (TRPH) in
surface soil and localized occurrences around the flight line. Polycyclic Aromatic
Hydrocarbons (PAHs) were detected in surface soil. Polychlorinated biphenyls
(PCBs, often formerly used for the lubrication of electric transformers) were
detected in surface soil at the northern edge of the flight line and current wash
rack. Solvents (volatile organic compounds and semi-volatile organic
compounds), pesticides, and metals were detected in shallow soil samples
collected throughout the area. The results of the investigation did not reveal
significant soil contamination in the areas of the specific units (drywells, oil/water
separators, wash racks, etc.) included in this study. PAHs were the major COPC
posing a potentially unacceptable health risk in CAOC 1. Total PAH
concentrations are summarized in Figures 2-2 and 2-3.
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2.6.3 CAOC2: Shop Areas
CAOC 2 consists of the area bounded by Worley Street on the south, Building 603
on the west, Shaw Avenue on the east, and the flight line and Fuel Farm area on
the north. It is located within the northeastern portion of the industrial area of
MCAS Yuma and occupies approximately 28 acres. This area was used between
the 1940s and the early 1980s for public works shops and vehicle maintenance.
Various chemical spills and disposals onto the ground surface were reported
throughout this area between the 1940s and 1980s. In addition, two underground
fuel storage tanks were found to be leaking and were replaced. Suspected waste
streams associated with this area include used oils, fuel-related wastes, used
paints, solvents, and vehicle-related wastes.
The primary finding of the field sampling and analysis program was the isolated
detection of residual TRPH and PAHs. Pesticides, Total Petroleum Hydrocarbons
(TPH) as diesel, volatile organic compounds (VOCs), semi-volatile organic
compounds (SVOCs), metals, and organic lead were also detected. The results of
the investigation did not reveal significant soil contamination in the areas of the
specific units (drywells, oil/water separators, former buildings, etc.) included in
RI field investigation.
2.6.4 CAOC 3: Auto Hobby Shop
CAOC 3 consists of an open area adjacent to the Auto Hobby Shop (Building 561)
at the southeast corner of Quilter Street and Halstead Avenue. The original
fenced area of CAOC 3 covered approximately 0.3 acres of unpaved land. The
ground surface outside the .Auto Hobby Shop was reportedly used for the
disposal of motor oil, cleaning solvents, battery acid, and anti-freeze between 1960
and the early 1980s. Stoddard solvent, commonly used to clean shop floors and
automotive parts, was also likely to have been disposed of within this area.
The primary finding of the field sampling and analysis program was the detection
of residual TRPH in the shallow soils underlying this area. However, no
individual components of TRPH, such as benzene, toluene, ethylbenzene, and
total xylenes (BTEX), were detected. Significant concentrations of other analytes
were not detected.
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2.6.5 CAOC 4: Radar Hill Disposal Area
CAOC 4, comprising approximately 14 acres, is located south of Radar Hill within
the central portion of MCAS Yuma (Figure 2-4). This area was used for burning or
burying municipal waste (household waste) generated at MCAS Yuma and, more
recently, for the disposal of construction debris, including broken concrete slabs.
Sometime during the 1950s, this area was covered with soil. Suspected waste
steams associated with this area include used oils, used paints, solvents, thinners,
vehicle-related wastes, pesticides, and herbicides.
The primary findings of the field sampling and analysis program were the
detection of residual TRPH and the isolated detection of PAHs and lead. Organics
and metals were also found in the shallow soils underlying this area. No
individual components of TRPH, such as BTEX, were found. The surface soil
samples collected from CAOC 4 did not contain detectable asbestos. However,
during the field sampling program, several debris piles were identified in which
potential ACM was noted. Subsequent analysis of these materials confirmed the
materials to be ACM (JEG, 1996).
2.6.6 CAOC 5: Old 2nd LAAMBN Compound
CAOC 5, occupying approximately two-thirds of an acre, is located within the
south-central portion of MCAS Yuma, south of Loesch Road between Baseball
Field 1268 and the residential housing area. This CAOC was the site of the 2nd
Light Anti-Aircraft Missile Battalion (LAAMBN) vehicle maintenance and storage
yard between the late 1960s and 1974. Routine vehicle servicing, maintenance,
and fueling operations have occurred within this area and have resulted in the
disposal and spills of fuel, motor oil, and solvents. In addition, used motor oil,
transmission fluid, cleaning and degreasing solvents (trichloroethene,
trichloroethane, and Stoddard solvent), antifreeze (ethylene glycol), and
neutralized battery acid were sprayed along the exposed soil ground surface for
dust control purposes.
The primary finding of the field sampling and analysis program was the detection
of residual TRPH. However, no individual components of TRPH, such as BTEX,
were detected. Pesticides, TPH as diesel, VOCs, SVOCs, and metals were also
detected.
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2.6.7 CAOC6: First Sewage Lagoon
CAOC 6 is located west of County Road 3E and south of Loesch Street in an area
currently used for military family housing. This area encompasses approximately
30 acres. Treated industrial sewage and municipal sewage (domestic sewage)
from MCAS Yuma was discharged into an unlined evaporation/infiltration
lagoon and sludge beds during the early 1940s. The sewage treatment facility
ceased operations in 1943 and was covered. The sludge was also buried in place
at that time, and in the 1970s, a housing development was constructed on top of
the buried lagoon and sludge beds. Suspected waste steams associated with this
area include vehicle-related wastes, used oils, solvents, thinners, paints, caustics,
photo processing wastes, herbicides, and pesticides.
The primary finding of the field sampling and analysis program was the detection
of residual TRPH. However, no individual components of TRPH, such as BTEX,
were detected. Solvents, pesticides and metals were also found in the shallow
soils underlying this area.
2.6.8 CAOC 7: Fire School Area
CAOC 7 is divided into two subunits: CAOC 7A (northern unit) and CAOC 7B
(southern unit). CAOC 7A, occupying approximately 40 acres, is located
southwest of Radar Hill and north/north west of the Combat Aircraft Loading
Apron (CALA) (Figure 2-5). CAOC 7B consists of several small debris piles
located south of the CALA (Figure 2-6). During the RI field investigation, only
CAOC 7A was investigated. CAOC 7B was investigated subsequently in an
investigation documented in MCAS Yuma - Asbestos Survey Results (JEG, 1995a).
CAOC 7A consists of 16 unlined fire pits that were used between 1952 and 1985
for fire training. The current lined fire pit (Facility 1220) has been used since 1985.
There are seven former fuel bladder areas that were used between approximately
1967 and 1984. Fires at CAOC 7A were created by floating flammables on water
in shallow, unlined pits. The fuel in the fire pit was ignited, and trainees
extinguished the fire. Water and unburned flammables were washed into the
surrounding soil and left to infiltrate. Suspected waste steams associated with this
area include aviation fuels, used oils, solvents, and thinners.
The primary finding of the field sampling and analysis program in CAOC 7A was
the widespread detection of residual TRPH, generally in former fire pits and fuel
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bladders. Low concentrations of VOCs, SVOCs, PCBs, pesticides, dioxins/furans,
TPH as diesel, and metals were also detected.
Small broken pieces of asbestos-containing materials were identified south and
east of the active fire-training pit. The area contaminated with ACM is
approximately 170,000 square feet. Over most of the unit, the ACM occurs only as
surface scatter. In a limited area near the active bum pit, the ACM contamination
reaches a maximum of one foot deep (up to 1,200 cubic yards). The RI (JEG, 1996)
concluded that asbestos is the only COPC at CAOC 7A that may pose a risk to
human health or the environment.
CAOC 7B consists of debris piles south of CALA: The area immediately south of
CALA has been used for dumping construction debris. Seven sites within this
area were confirmed to contain ACM debris. These sites consist of isolated,
coherent piles (in one case, a single piece) containing one or more of the following
types of ACM: floor tile with asbestos-containing mastic, transite, and/or ACM
pipe. The total volume of ACM debris is approximately 10 cubic yards (JEG,
1995a).
2.6.9 CAOC 8: Southeast Station Landfill
CAOC 8 is located within the southeastern portion of MCAS Yuma, between
Loesch Street and the southern Station property lines. This area was subdivided
into two units: CAOC 8A (southern unit) and CAOC 8B (northern unit)
(Figure 2-7). CAOC 8A includes a landfill that was used to dispose of waste
generated at MCAS Yuma, and CAOC 8B includes the housing development that
now covers the area north of Ordnance Road. Combined, CAOCs 8A and 8B
occupy approximately 68 acres. This area was used primarily for the disposal of
municipal wastes that were generated at MCAS Yuma between 1953 and 1961.
Before disposal, most of the wastes were burned. During disposal, approximately
10 to 20 pits were used for the burial of wastes. A portion of the area was used for
rubble disposal and as a borrow area for fill soil. At an unknown date, the pits
were backfilled, and housing units were developed. Suspected waste streams
associated with this area include vehicle-related wastes, used oils, solvents,
thinners, paints, fuel-related wastes, pesticides, and herbicides.
Drilling within the landfill was not performed because of potential drilling
hazards and difficult drilling conditions caused by construction debris buried in
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the landfill. Therefore, the landfill investigation was directed at evaluating the
exposure scenario for the present site conditions and future (capped) conditions.
The primary findings of the field sampling and analysis program were the
detection of residual TRPH, PAHs, PCBs, solvents, pesticides, and metals in the
shallow soils underlying this area. These contaminants were generally found in
the portion of the CAOC south of North Ordnance Road. Low levels of
trichloroethene, tetrachloroethene, xylenes, and methane were also detected in soil
gas samples. PCBs were the major COPC posing a potentially unacceptable health
risk for current land uses at CAOC 8A.
2.6.10 CAOC 9: Southeast Sewage Lagoon
CAOC 9 is located within the southeast corner of MCAS Yuma, southwest of the
intersection of North Ordnance Road and County Highway 3E (Figure 2-8). This
CAOC formerly consisted of two Imhoff tanks, sludge drying beds, and six
lagoons occupying approximately 14 acres. This area was used for wastewater
treatment between 1944 and 1970, when the Station began discharging to the
Yuma wastewater treatment plant. The sewage lagoons were unlined.
Periodically, the sludge beds were scraped for cleaning. The lagoons were closed
in 1970. The sludge was left in place and covered with fill materials. Suspected
waste streams associated with this area include used oils, used paints, solvents,
thinners, and photograph processing waste.
The primary findings were the detection of residual TRPH in near-surface soil and
the isolated detection of PAHs. Metals detected above RBC at CAOC 9 were
antimony, arsenic, and lead, but the RI (JEG, 1996) concluded that the elevated
metal concentrations detected in the samples were anomalous and were not
representative of concentrations at the CAOC.
Asbestos was not detected in the surface soil samples. However, asbestos was
detected in samples from one debris pile north of the horse stables within the
CAOC. The RI (JEG, 1996) concluded that the asbestos at CAOC 9 was the only
COPC that may pose a risk to human health or the environment.
2.6.11 CAOC 10: Ordnance Munitions Disposal Area
CAOC 10 was used during World War II as a shooting range for bomber gun
crews (Figure 2-9). Since the early 1950s, ordnance materials have been stored in
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magazines around the central portion of Ordnance Loop Road. The area has also
been used for surface tank and drum storage. Surface spills have been reported
within this area. This area continues to be used for the storage and handling of
ordnance. Suspected waste steams associated with this area include used oils,
ordnance waste associated with nitroaromatics, fuel-related wastes, and metals.
The primary finding of the field sampling and analysis program was the detection
of TRPH, PAHs, and one anomalous lead concentration in surface soil. PAHs
were detected in surface soil at four locations during the RI. Follow-up sampling
programs in August 1996 and February 1997 (U&A, 1996d; U&A, 1997)
demonstrated the presence of PAHs over a wider area than indicated by the RI.
Several sampling locations had total PAH concentrations an order of magnitude
higher than were detected in the RI. Figure 2-10 shows the total PAH
concentrations detected in the August 1996 and February 1997 samples with the
isoconcentrarion contours defined in the RI Report. Although the August 1996
and February 1997 data support the presence of elevated PAH concentrations at
the four areas of elevated PAHs identified in the RI Report, the later data also
indicate that elevated PAH concentrations are present at locations that do not
correspond to features identified based on aerial photographs or geophysical
anomalies*
2.6.12 CAOC11: Radiation Disposal Pipes
CAOC 11 is located near the south-central boundary of MCAS Yuma, south of
CAOC 10 and west of CAOC 8. During Air Force operations (between 1951 and
1959), two sealed iron pipes containing radioactive material (electron tubes,
luminous markers, radium dials, and radium knobs) were buried at this location.
The pipes were examined in April 1980 and subsequently removed and disposed
of off Station. Swipe tests on each pipe indicated the presence of radium 226 at
less than one microcurie QEG, 1996). Soil samples from the burial pit were
analyzed and compared to soil from 20 to 200 feet away. No signs of residual
radiation were found in the soil. Because radiological contamination was not
detected during the radiological characterization survey, the RI concluded that
additional soil sampling was not necessary.
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2.6.13 CAOC12: Tear Gas Burial Area
CAOC 12 is located within the southwestern portion of the Station, approximately
550 feet northwest of Building 1597 on the southern edge of the Combat Aircraft
Loading Apron (CALA). This area comprises approximately 0.4 acre. The Marine
Wing Weapons Unit (MWWU) was constructed in 1962, at which time this area
consisted of an unpaved road that led to the MWWU. Between 1977 and 1978, 300
pounds of dry crystal tear gas were reported to have been buried at this site. Oil
was also reported to have been sprayed across the surface of this area for dust
control purposes. This area was graded in late 1984 when the CALA was
constructed; no tear gas bags were revealed. The bags may be buried deeper than
the soils excavated during grading activities or the contents may have been mixed
with the soil. Suspected waste steams in this area include tear gas waste
(including solvents) and trihalomethanes. Two VOCs, methylene chloride and
toluene, and three SVOCs were detected in soil samples; all detected values were
below RBC values (See Section 2.10.5). The RI found no evidence of tear gas
wastes at this CAOC.
2.6.14 CAOC 13: Drain Field Area
CAOC 13 consists of the drain field that was formerly used for the MWWU
compound when it was located at the end of Hamilton Street. This drain field is
beneath the 14-inch-thick concrete at CALA, which is located within the
southwestern portion of the center of MCAS Yuma, approximately 500 feet
northwest of Building 1597. This area covers approximately two acres of land.
The MWWU compound was constructed in 1962 and operated until 1984, when it
was replaced by CALA. Liquid rinsates from filling and mixing equipment used
for simulated chemical weapons (tear gas and napalm) at the MWWU were
disposed of at a drain field south of former Building 1585. An estimated one
million gallons of wastewater were discharged to the drain field between 1970 to
1985. Suspected waste steams associated with this CAOC include used oils, fuel-
related wastes, solvents, and thinners. PAHs, pesticides, and metals were
detected within the shallow soils beneath this area.
2.6.15 CAOC 14: Drain Field South of Building 97
CAOC 14 is located north of Building 40 and south of Building 97, comprising an
area of approximately one acre. A lagoon south of Building 97 has been used for
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the collection of surface stormwater runoff since 1955. In 1985, another lagoon
area was constructed northwest of Building 40; in 1989, the lagoon was extended
to the northeast. These pit configurations currently direct stormwater to the area
northwest of Building 40. Suspected waste streams within this area include used
oils, fuel-related waste, solvents, and thinners.
The primary finding of the field sampling and analysis program was the detection
of residual TRPH and isolated PAHs. However, no individual components of
TRPH, such as BTEX, were detected. Solvents, pesticides, PCBs, and metals were
also detected in the shallow soils beneath this area.
2.6.16 CAOC15: Hazardous Waste USTs 363 and 364
CAOC 15 is located at the Fuel Farm within the northeastern comer of MCAS
Yuma, east of the flight line. This area, which occupies approximately 0.3 acre,
formerly contained two underground storage tanks (USTs). The USTs were
installed in 1943 and removed in 1987, after they failed a leak test. Suspected
waste streams within this area include used oils, fuel-related waste, used paints,
solvents, and thinners. Hydrocarbons, solvents, and metals have been detected in
the shaltow soils underlying this area.
2.6.17 CAOC 16: Hazardous Waste USTs, Building 230-2 and 230-4
CAOC 16 is located within the northeastern comer of the flight line, adjacent to
Building 230, the Airframe Shop. Both tanks were removed in 1989. Tank 230-2
was reported to be leaking, and tank 230-4 failed a leak test. Suspected waste
streams in this area include used paints, solvents, and thinners.
The sampling and analysis of soil samples detected residual TRPH concentrations.
However, no individual components of TRPH, such as BTEX, were detected.
Trichloroethene (in one sample only), SVOCs and metals were also detected.
Metals were all within background levels.
2.6.18 CAOC 17: Hazardous Waste Underground Storage Tank 1708-3
CAOC 17 is the former location of a UST adjacent to Building 1708 within the
southwest portion of MCAS Yuma. The UST was installed in 1985 to collect
rinsate from the decontamination pad adjacent to Building 1708. The tank was
abandoned in 1988 and removed in 1995. At the time the UST was removed, three
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soil samples were collected beneath the tank for laboratory analysis. The
analytical results did not reveal the presence of TRPH or halogenated VOCs,
indicating that a past release from the tank had not occurred. Waste streams
associated with this area include used oils, fuel-related waste, solvents, thinners,
and vehicle-related waste.
The primary finding of the field sampling and analysis program was the detection
of residual TRPH. However, no individual components of TRPH, such as BTEX,
were detected. In addition, SVOCs, pesticides, and metals were detected, but the
metals were within background ranges.
2.6.19 CAOC18: Old Drum Storage Area
CAOC 18, comprising approximately 0.45 acres, is located within the northeastern
corner of MCAS Yuma, north of the Fuel Farm. Approximately 102 55-gallon
drums were stored within a fenced area between 1987 and 1989. The drums,
which contained investigation-derived wastes and waste personnel protective
equipment, were removed and crushed in 1990, and the area is currently vacant.
No historical information suggests the storage of waste within this area before
1987. Suspected waste streams include used oils, fuel-related waste, used paints,
solvents, thinners, vehicle-related wastes, photo processing waste, and
nirroaromatics.
The primary finding of the field sampling and analysis program was the detection
of residual TRPH and isolated PAHs. However, no individual components of
TRPH, such as BTEX, were detected. Solvents, pesticides, and metals have also
been detected at isolated locations in the shallow soils underlying this area.
2.7 Highlights of Community Participation
The Community Relations Program was designed and implemented in accordance
with the Community Relations Plan QEG, 1994a). This program is intended to
both inform the public and to provide the public with opportunities to participate
in the decision-making process for environmental cleanup at the Station. A
Restoration Advisory Board (RAB), comprising representatives from the Navy,
U.S. EPA, the Arizona Department of Environmental Quality, and members of the
general public, has been established and meets periodically to involve the public
in decisions regarding investigation results, proposed work, and potential
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remedial options. The Navy has also presented RI plans and results at public
meetings conducted on January 18 and April 11,1996.
The Navy has prepared a Proposed Plan for OU2 at MCAS Yuma for public
review and comment. The plan was presented on March 20,1997. The Proposed
Plan summarizes information collected during the OU2 Preliminary
Assessment/Site Inspection (PA/SI) and Remedial Investigation/Feasibility
Study (RI/FS) and other documents that are available at the local repositories.
Comments regarding the Proposed Plan were accepted during a 30-day public
review and comment period that extended from March 21,1997 to April 28,, 1997.
A public meeting was held on April 9, 1997, to provide the community an
opportunity to ask questions and express concerns about the Plan. Responses to
comments received during the public comment period are included in the
Responsiveness Summary (Section 3) of this ROD. The public comment period is
a continuation of the Navy's commitment to community involvement in the
MCAS Yuma IRP and is required by CERCLA.
2.8 Scope and Role of Operable Unit 2
0
Response actions for MCAS Yuma are addressed as Operable Units (OUs). Two
OUs have been identified at MCAS Yuma. OUl addresses contamination of
groundwater and soils greater than 10 feet below the ground surface. OU2
consists of surface disposal and disposal units within the upper 10 feet of soil
underlying the Station, where disposal or releases of petroleum products, paints,
solvents, metals, pesticides, and other process chemicals may have occurred. OU2
is limited to depths of 10 feet because this is the maximum likely depth for
footings associated with any new construction at MCAS Yuma. This ROD
documents the remedial action plan for OU2. Remedial objectives and goals for
OUl will be addressed in a separate ROD.
The OU2 IRP has the following objectives:
Evaluate the environmental condition of the CAOCs
Identify potential threats to human health or the environment
Develop cleanup actions to protect human health and the environment
The RI investigated 18 CAOCs at which surface or near-surface disposal or
releases of wastes may have occurred. The investigation of OU2 was limited to an
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assessment of the risk/hazard posed by contaminants in the upper 10 feet of soil.
No risk to the environment was identified at the 18 CAOCs (See Section 2.11).
Based on the human health risk assessments summarized in Section 2.10,15 of the
18 CAOCs are acceptable for residential land use, while chemicals identified at
CAOCs 1 and 10 present acceptable health risks if their current, non-residential
land uses are maintained. Since the chemical contents of CAOC 8A (the inactive
Southeast Station Landfill) are not known, activities that disturbed the interior of
the landfill would have an unknown impact on human health risks. Institutional
controls will be implemented for CAOCs 1, 8A, and 10 to minimize potential
health risks that might be associated with land use changes at these CAOCs.
ACM, which was not included in the quantitative risk assessments because risk
criteria have not been established for asbestos, was identified in three of the 15
CAOCs that were assessed to be otherwise acceptable for residential land use.
The ACM at these three CAOCs (4, 7, and 9) is the only material within OU2 for
which remedial actions are recommended.
No remedial action is recommended for the 12 CAOCs that are acceptable for
residential land use and have no identified ACM. Although these areas do not
present human health risks or ecological risks, they are still referred to as CAOCs
(CERCLA Areas of Concern) in this document because, although the term
"CAOC" is used to identify a potentially hazardous site, a CAOC is not
necessarily a site that requires remediation.
2.9 Summary of Field Investigation
The field sampling effort was preceded by extensive scoping activities that
included a records search, personnel interviews, an aerial infrared thermographic
survey, and acquisition and interpretation of aerial photographs. Information was
also obtained from geophysical subsurface surveys (magnetic and
electromagnetic) that identified anomalies at several CAOCs. Geophysical
surveys were performed at CAOCs 4, 8, 9,10,14,16, and 17.
Based on past and current activities at the CAOCs, several potential waste streams
were identified, including lubricating oils, fuel products, paints and waste paints,
solvents and thinners, vehicle-related wastes, photographic processing materials,
pesticides, and herbicides. These waste streams were used as the primary basis in
the selection of chemicals of potential concern (COPC) at each CAOC. COPCs are
listed in Table 2-1.
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The RI field investigation program included soil gas surveys and soil sample
collection and analyses. Analyses for COPCs were performed at an off-site and an
on-site laboratory. The on-site laboratory provided data that were used for rapid
soil screening, while the off-site laboratory data were used in the risk assessments
for the CAOCs. Narrative summaries of the primary findings of the field
investigation for each of the 18 CAOCs in OU2 are included in Sections 2.6.2
through 2.6.19.
Tables 2-2 through 2-5 summarize maximum concentrations of volatiles,
semivolatiles, pesticides, and metals detected in samples submitted to the off-site
laboratory at each CAOC, as well as the RBC values calculated for each COPC
(Section 2.10.5). Off-site data are summarized in these tables because only off-site
data were used in the human health risk assessment. Samples submitted for off-
site analysis consisted of confirmatory splits of samples analyzed by the on-site
laboratory and samples collected from suspected "hot spots". Hot spots are
localized regions where COPC concentrations exceed risk based criteria (See
Section 2.10.5). Table 2-5 also includes the CAOC-specific background levels (or
TLV values) for the metals. An evaluation of potential human health and
ecological risks is presented in Sections 2.10 and 2.11.
»
2.10 Summary of Risk Assessment
2.10.1 Human Health Risk Assessment
Human health risk assessments were performed on a site-by-site basis for the 18
CAOCs within OU2. A detailed discussion of the risk assessment procedures is
presented in Section 4.16 and Appendix P of the RI Report (JEG, 1996). Results of
the risk assessment are included in the site-by-site discussions in Sections 6
through 22 of the RI Report. The human health risk assessment includes the
identification of the COPCs, exposure assessment, toxicity assessment, and the
development of risk-based concentrations (RBC). The individual components of
the risk assessment process are described below.
2.10.2 Identification of COPCs
The COPCs included in the risk assessment process included target analytes that
were detected during the field sampling for OU2. Table 2-1 presents the target
analytes that constituted potential COPCs. Note that asbestos was not included in
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the quantitative risk assessment because there are no established risk criteria for
asbestos. The criteria for exclusion of a detected analyte from risk-based screening
are given below:
Metals that are essential human nutrients. These metals include calcium, iron,
magnesium, potassium, and sodium.
Metals that did not exceed local background values; these background values
were expressed as threshold limit values (TLVs).
Analyte concentrations less than 10 times those detected in the method blank
for common laboratory contaminants. Analytes considered common
laboratory contaminants include acetone, methylene chloride, and phthalates.
The exclusion criteria stipulated are consistent with U.S. EPA recommended
procedures (U.S. EPA, 1992a).
Analytes that have no published toxicity data available (i.e., cancer potency
factors or reference doses as published in the Integrated Risk Information
System (IRIS) and the Health Effects Assessment Summary Table (HEAST)).
Analytes detected at sampling depths greater than 10 feet.
Unquantified compounds (e.g., unknown ketones).
Threshold limit values (TLVs) were calculated for all CAOC-specific metals data
using an U.S. EPA-approved method (U.S. EPA 1989a) that determines how many
standard deviations from the mean are required to have 95 percent confidence
that the upper threshold of a normal population is at the 95th percenrile. The TLV
method uses a K-factor that is inversely related to the size of the population data
set (i.e., as the population size increases the K-factor decreases). TLV values for
the individual CAOCs are included in Table 2-5.
The maximum concentrations from the off-site laboratory samples taken at hot
spot and confirmatory splits from the upper five feet of soil were evaluated in the
ecological risk assessment; those from the upper 10 feet of soil were evaluated for
the human health risk assessment. Risk assessments were not performed for
CAOC 11 or CAOC 15. At CAOC 11, soil samples were not collected, because
only a radiological survey was performed. At CAOC 15, soil samples were only
collected from depths greater than 10 feet, because the investigation was focused
on a UST buried beneath this depth.
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2.10.3 Exposure Assessment
Exposure is the contact of a receptor (human or ecological) with a chemical or
physical agent. Exposure magnitude is determined by estimating the amount of
the contaminant (analyte) available at the exchange boundary (skin, lungs) during
a specified period of time. Exposure assessment is the determination of the
magnitude, frequency, duration, and pathway and route of exposure. The RI
exposures were assessed for reasonable maximum exposure (RME) scenarios,
which represent an upper-bound conservative exposure that is within the range of
possible exposures. If the receptor is exposed via more than one route (e.g.,
dermal contact, inhalation, etc.), the combination of exposures across all relevant
routes must also represent an RME.
Because ground water issues are included in the IRP for OU1, and surface water is
not present at MCAS Yuma, potential pathways for released contaminants are
limited to the following:
Incidental ingestion of soil contaminants
Dermal contact with soil contaminants
Inhalation of volatile emissions from soil
Inhalation of suspended soil particulates
Exposure scenarios were developed for both current and future land uses at
MCAS Yuma. Because the future land use scenarios involve a higher degree of
exposure to chemicals at MCAS Yuma, risk management decisions were made on
the basis of the future use scenarios. Use of the future use scenarios, therefore,
provided a more conservative estimate of risk.
Exposure scenarios for current uses at MCAS Yuma included the following:
military workers, for the CAOCs that are currently industrial /commercial; and
military children, for those CAOCs in close proximity to base housing. For both of
these scenarios, the risk assessment used an exposure duration of three years,
which was considered to be an upper bound of the typical duty assignment at
MCAS Yuma (JEG, 1996).
Future use scenarios were developed assuming that MCAS Yuma was no longer
operative and the property would be re-developed for either residential housing,
industrial/commercial, or agricultural activities. RME exposure scenarios were
evaluated in terms of either an industrial /commercial scenario or a residential
scenario; these two scenarios provided more significant exposure than the
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agricultural exposure scenario. The RME future use scenarios used standard U.S.
EPA-approved default exposure parameters. In particular, the residential
exposure scenario used .in the assessment is not representative of base housing,
but is based on future residential land use and represents an RME scenario of a 30-
year lifetime exposure. Similarly, the industrial exposure scenario for future use
includes a 25-year exposure period, rather than the three-year exposure period for
military workers. Both residential and industrial/commercial exposure scenarios
were used for all CAOCs, although only CAOCs 4, 6, and 8 are actually located at,
or adjacent to, residential housing. RBC values in Tables 2-2 through 2-5 are for
the future use scenarios, because these represent the most conservative RBC
values.
Note that the Arizona Health Based Guidance Levels (HBGL) discussed in the
ARAR discussion in Section 2.13.4 are derived using the assumption that
incidental ingestion of soil contaminants is the only significant exposure pathway.
Therefore, the RBC values (See Section 2.10.5) are more conservative than the
HBGL values. HBGL values are derived by ADEQ for residential and non-
residential scenarios that are analogous to the future use industrial/commercial
and residential scenarios used in developing RBC values.
»
2.10.4 Toxicity Assessment
Exposure to the identified constituents of concern may, in sufficient
concentrations, adversely effect human health. Therefore, U.S. EPA has
developed Cancer Potency Factors and References Doses to evaluate potential
toxicity.
Cancer potency factors (CPFs) have been developed by U.S. EPA's Carcinogenic
Assessment Group for estimating excess lifetime cancer risks associated with
exposure to potentially carcinogenic chemicals. CPFs, which are expressed in
units of (mg/kg-day)', are multiplied by the estimated intake of a potential
carcinogen, in mg/kg-day, to provide an upper-bound estimate of the excess
lifetime cancer risk associated with exposure at that intake level. The term "upper
bound" reflects the conservative estimate of the risks calculated 'from the CPF.
Use of this approach makes underestimation of the actual cancer risk highly
unlikely. Cancer potency factors are derived from the results of (1) human
epidemiological studies or (2) chronic animal bioassays to which animal-to-
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human extrapolations and uncertainty factors have been applied to account for
the use of animal data to predict the effects on humans.
Reference doses (RfDs) have been developed by U.S. EPA for indicating the
potential for adverse health effects from exposure to chemicals exhibiting
noncarcinogenic effects. RfDs, which are expressed in units of mg/kg-day, are
estimates of lifetime daily exposure levels for humans, including sensitive
individuals. Estimated intakes of chemicals from environmental media (e.g., the
amount of chemical incidentally ingested with soil) can be compared to the RfD.
RfDs are derived from (1) human epidemiological studies or (2) animal studies to
which uncertainty factors have been applied to account for the use of animal data
to predict the effects on humans. These uncertainty factors help ensure that the
RfDs will not underestimate the potential for adverse noncarcinogenic effects to
occur.
2.10.5 Development of Risk-Based Criteria
Risk-based criteria (RBC) are chemical-specific concentrations for a given set of
exposure assumptions (e.g., residential, military worker) and for a particular
medium (e.g., soil). For the OU2 RI, COPCs in soil were the only evaluated
medium (Note: This medium includes volatilization of organics from soil).
The maximum COPC values at each CAOC were compared to RBC. These RBC
values are functions of the inherent toxicity of the individual COPC and the
default exposure parameters for each of the evaluated exposure scenarios.
Consequently, different RBC values were derived for each exposure scenario that
was considered probable at MCAS Yuma. The algorithms and the description of
the methodology used to calculate RBC are presented in Appendix P of the RI
(JEG, 1996).
RBC for carcinogenic compounds were calculated by inserting the appropriate
exposure parameters and toxicity values into the chemical intake equation, and
setting the target cancer risk summed over all probable pathways equal to 10'6.
The 10"6 risk level is considered de minimus;-a risk level exceeding 1(H is the level
that generally warrants action at a site. An excess lifetime cancer risk of 1 x 10"6
indicates that, as a plausible upper bound, an individual has a one in one million
chance of developing cancer as a result of site-related exposure to a carcinogen
over a 70-year lifetime under the specific exposure conditions at a site. RBC
values for noncarcinogenic effects were calculated similarly with the target
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noncarcinogenic hazard index (HI) set equal to 1.0. An HI equal to or less than 1.0
identifies a level of exposure to the chemical at which even sensitive populations
are unlikely to experience adverse health effects. For chemicals with both
carcinogenic and noncarcinogenic health effects, RBC values were determined for
each of these health effects.
Note that the Arizona Health Based Guidance Levels (HBGL) discussed in the
ARAR discussion in Section 2.13.4 are derived using a target cancer risk of 1 x 10"*
for carcinogens and a HI of 1.0 for noncarcinogens.
RBC were used to evaluate cumulative cancer risk and/or non-cancer hazard at
each CAOC. Selected samples (10 percent splits) from the on-site samples were
sent to an off-site laboratory for analysis. The maximum soil concentration
detected at the off-site laboratory for each analyte detected at the CAOC was
compared to the cancer and/or noncancer RBC for that analyte. Risk quotients
were calculated by dividing the maximum concentration of the analyte by the
applicable RBC for carcinogenic compounds. For carcinogens, a risk quotient of 1
is equivalent to a cancer risk of 10*, while a risk quotient of 10 is equivalent to a
cancer risk of 10"5. Hazard quotients for non-carcinogenic COPCs were calculated
similarly. The carcinogenic and non-carcinogenic quotients for each analyte were
then each summed to provide CAOC-specific cumulative indices.
2.10.6 Summary of Risks at Individual CAOCs
Introduction
Health risks were calculated for OU2 on a CAOC-by-CAOC basis. For each
CAOC, risks were calculated for both residential and industrial use scenarios. The
RBC values and maximum COPC values that were used for each CAOC-specific
risk assessment are included in Tables 2-2 through 2-5. Calculated excess lifetime
cancer risks are within the range of acceptable risk defined by the U.S. EPA (10*6
to 10"*) (U.S. EPA 1994c) for current land uses. However, as discussed below,
excess cancer risks for unrestricted land use (residential) may be higher than
acceptable at CAOCs 1 and 10. The calculated excess cancer risks for these two
CAOCs are discussed below. Since the chemical contents of CAOC 8A (the
inactive Southeast Station Landfill) are not known, potential cancer risks
associated with exposure to the landfill interior are not known. Based on the RI,
U.S. EPA, ADEQ, and the Navy concluded that HI values were acceptable for
residential exposure at 16 of the CAOCs and that HI values were acceptable for
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industrial exposure at the remaining CAOCs, 1 and 10. The following discussion
focuses on cancer risk at CAOCs 1,8A, and 10.
CAOC1: Flight Line
The excess cancer risk for CAOC 1 is 6.48 x 10'5 for the commercial/industrial
exposure scenario. Approximately 90 percent of the excess CAOC cancer risk is
attributable to PAHs, 4 percent to PCBs, 2 percent to pesticides, and 4 percent to
metals. The RI concluded that the 0- to 10-foot soils at CAOC 1 do not pose an
unacceptable risk to human health under the commercial/industrial use scenario,
which coincides with the current use of the CAOC (JEG, 1996).
For a residential exposure scenario, the calculated excess lifetime cancer risk is
2.19 x 10"4, 83 percent of which is attributable to PAHs. The excess lifetime cancer
risk at CAOC 1 is greater than the acceptable range for an unrestricted residential
use scenario.
CAOC 8A: Southeast Station Landfill South of North Ordnance Road.
The portion of CAOC 8 south of North Ordnance Road has been designated
CAOC 8A, Landfill/Surface Disposal Area. In CAOC 8A, Landfill/Surface
Disposal Area, the excess cancer risk is 9.94 x 10'5 for the residential exposure
scenario, which is at the upper end of the acceptable range of risk (10"6 to 10"4)
defined by the U.S. EPA. PCBs contribute approximately 74 percent of the overall
cancer risk. Aroclor-1254 was detected at three surface sampling locations at soil
concentrations of 4.045, 0.99, and 0.32 mg/kg. For a commercial/industrial
exposure scenario, the excess cancer risk is 3.02 x 10'5. Based on the fact that the
landfill interior has not been fully characterized and therefore the human health
risks associated with exposure to the landfill interior are not known, U.S. EPA,
ADEQ, and the Navy have made a risk management decision to restrict the use of
CAOC 8A to the current use and to prohibit any land use that could potentially
disturb the interior of the landfill.
The maximum concentration of lead detected at CAOC 8A (659 mg/kg) is greater
than the U.S. EPA Region 9 residential soil screening value of 400 mg/kg.
Therefore, lead represents a potential health risk for future residents at the CAOC
8A Land fill/Surface Disposal Area.
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CAOC 10: Ordnance Munitions Disposal Area
The excess cancer risk calculated from the RI data is 7.62 x 10~5 for the residential
exposure scenario and is primarily attributable to PAHs. Benzo(a)pyrene is the
PAH driver, with an incremental cancer risk of 5.62 x 10~5. The excess cancer risk
for the industrial exposure scenario is 2.42 x 10"5.
Based on data from the August, 1996 and February, 1997 field investigations and
the RBCs derived in the RI, the excess cancer risk from PAHs for the residential
exposure scenario was recalculated as 4.6 x 10"* and for the industrial scenario,
1.5 x 10"4 (U&A, 1997). The recalculated industrial excess lifetime cancer risk is at
the up'per end of the range of risks that are potentially acceptable for industrial
exposure scenarios.
The RI Risk-Based Criteria (RBCs) used to calculate carcinogenic risk were
developed in 1993 using U.S. EPA exposure factors. U.S. EPA's dermal exposure
factors have since been revised. If the RBCs were calculated with the current
(1996) EPA-approved factors, the RBCs for PAHs would be identical to U.S. EPA
Preliminary Remediation Goals (PRGs). Using the same data and calculating the
risks using PRGs, the industrial and residential excess lifetime cancer risks are
7.0 x 10"s and 2.9 x 10"4, respectively. The industrial excess lifetime cancer risk
calculated with PRGs is in the middle of the range of risks that are acceptable for
industrial exposure scenarios.
Conclusion
The risk assessment performed for the 18 OU2 CAOCs indicates that constituents
detected in the soil do not pose a significant risk to human populations under
current use scenarios. However, at CAOCs 1, 8A, and 10 risks for unrestricted
land use may be higher than acceptable. In addition, asbestos was not included in
the risk assessment because no risk criteria have been established for asbestos.
ACM was identified at three of the CAOCs. The major risk associated with
asbestos is the potential for inhalation of airborne asbestos fibers. Asbestos
exposure can cause a number of disabling and fatal diseases. The risk of
developing asbestos-related disease is related to the intensity, duration, and
nature of the exposure. Large doses of asbestos fibers are clearly linked to a
higher incidence of disease. The amount of ACM in the CAOCs at MCAS Yuma is
relatively low, and exposure would only occur in the open air. Therefore, the
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potential for humans to inhale significant amounts of airborne asbestos fibers
from the ACM in soils is extremely low; air monitoring conducted during the RI
did not detect any asbestos fibers. Risks to ecological receptors from ACM in the
environment have not been documented. Although current risks from ACM are
low, weathering of ACM in the soils could degrade the ACM and release fibers
into the environment. These fibers could become airborne. For this reason, a risk
management decision has been made to take remedial action.
Hazardous substances from this site present a substantial threat of release, which
may pose a significant risk to human health and the environment if not addressed
by implementing the response action selected in this ROD (see Section 2.14).
2.11 Summary of Ecological Risks
The objective of the ecological risk assessment was to evaluate the impact to the
environment if remedial actions are not taken. A phased approach was used. The
first step, Qualitative Assessment, screened areas based on the physical, chemical,
and biological attributes and the potential for a complete exposure pathway.
CAOCs with no significant exposure pathways were recommended for no further
ecological investigation. The second step was to further evaluate CAOCs with
significant exposure pathways by comparing concentrations of chemicals of
potential ecological concern (COPECs) with ecological soil screening criteria. Soil
screening criteria are discussed in Section 4.16 of the RI Report and derived in
Appendix Q of the RI report QEG, 1996). COPEC concentrations exceeding soil
screening criteria were identified as posing a potential risk to vertebrate receptors.
Conversely, COPECs that did not exceed soil screening criteria were concluded to
not pose a risk. If a CAOC contained COPECs exceeding screening criteria, other
supporting evidence was used to identify whether a significant impact had
occurred or was likely to occur.
With the exception of migratory birds that have been observed in the airspace
above MCAS Yuma, no state or federally listed threatened or endangered species
are currently known to be present at MCAS Yuma. No critical habitats or habitats
of endangered species are affected by COPECs at OU2.
In general, the COPECs identified at the CAOCs are fairly immobile and the
majority of detected inorganic risk drivers can be attributed to background. In
addition, the majority of the CAOCs either have only a small portion of the CAOC
that could provide contact between receptors and potentially contaminated soil,
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have been significantly altered by vehicular traffic and disposal activities, or have
only a limited area of remaining natural habitat. Therefore, the ecological risk
assessment performed for the 18 OU2 CAOCs indicated that constituents detected
in the soil and surface water do not pose a significant risk to ecological receptors.
2.12 Description of Alternatives
2.12.1 Introduction
Based upon the human health and ecological risk assessments, U.S. EPA, ADEQ,
and the Navy agreed that no further action is required at 12 of the 18 CAOCs to
protect human health or the environment. However, because of the presence of
ACM in three CAOCs, remedial action (cleanup) is required to protect human
health, since the ACM could release asbestos fibers into the environment if left to
weather under current conditions. In addition, institutional controls are necessary
for CAOCs 1, 8A, and 10 to minimize potential health risks that might be
associated with land use changes at these CAOCs.
2.12.2 CAOCs Requiring Remediation of ACM in Soil
*
The OU2 RI identified CAOCs 4, 7, and 9 as containing ACM. These CAOCs were
evaluated in the FS for remedial action (U&A, 1996b). Two of the CAOCs have
been divided into soil remedial units; a remedial unit is defined as the area or
volume of ACM or ACM-contaminated soil to be remediated. The following
describes the lateral and vertical extent of ACM in soil requiring remedial action.
CAOC 4Radar Hill Disposal Area
CAOC 4 is located south of Radar Hill in the central portion of MCAS Yuma
(Figures 1-2 and 2-4). Two areas were confirmed to contain ACM:
4A Area north of Building 38 and east of Building 40: Small pieces of
asbestos-containing transite, cement pipe, and roofing materials mixed
with soil and other construction debris. The ACM was observed scattered
over the surface in an area of approximately 56,400 square feet. A field
investigation found that the contamination extended to approximately
seven feet in depth in a limited area of approximately 12,550 square feet
near the central portion of the unit (approximately 4,000 cubic yards after
excavation).
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4B Area west of Radar Hill: One debris pile containing approximately three
cubic yards of ACM fiberboard is located in this area.
CAOC 7Fire School Area and Debris Piles South of the Combat Aircraft
Loading Apron (CALA)
CAOC 7 contains two remedial units designated CAOC 7A (Fire School Area)
(Figure 2-5) and CAOC 7B (Debris Piles South of CAM) (Figure 2-6).
7A Fire School Area: Small broken pieces of asbestos-containing transite
siding and transite pipe were observed at the surface south and east of the
active fire-training pit. The area contaminated with ACM is approximately
179,000 square feet. Over most of the unit, the ACM occurs only as surface
scatter. In a limited area near the active bum pit, the ACM contamination
reaches a maximum of one foot deep (up to 1,200 cubic yards after
excavation).
7B Debris Piles South of CALA: The area immediately south of CALA has
been used for dumping construction debris. Seven sites within this area
were confirmed to contain ACM debris. These sites consist of isolated,
coherent piles (in one case, a single piece) containing one or more of the
following types of ACM: floor tile with asbestos-containing mastic,
transite, and/or ACM pipe. The total volume of ACM debris is
approximately 10 cubic yards.
CAOC 9Horse Stable Area
A small pile of construction debris, north of the horse stable, was confirmed to
contain asbestos-containing mastic (cement) adhered to non-ACM riles
(Figure 2-8). The maximum volume of ACM at this CAOC is estimated to be less
than one cubic yard.
2.12.3 Alternatives Considered for Remediating CAOCs 4,7, and 9
Four alternatives have been developed and evaluated for the remediation of ACM
at MCAS Yuma. The alternatives are listed and described below.
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Alternative 1No Action
The No-Action alternative was used as a baseline alternative against which other
alternatives were judged. With this alternative, there would be no action to treat,
contain, or remove any of the surface ACM or ACM-contaminated soil. In the
long term, ACM fragments may degrade and release asbestos fibers into the
environment. Short-term conditions would remain unchanged. There are no
costs associated with this alternative.
Alternative 2Cleanup of Surface ACM Debris
Under this alternative, ACM fragments visible on soil surfaces would be collected
manually. Collection would include removing approximately the upper inch of
soil beneath the ACM to reduce the potential for asbestos fibers remaining behind
in the soil. The ACM and soils would be stockpiled, manifested, loaded,
transported, and disposed of at a permitted facility.
The ACM mixed with soils beneath the surface in CAOCs 4A and 7A would
remain in place. Because ACM would remain in place in the eastern portion of
CAOC 4A, this area would require long-term maintenance to prevent buried
ACM from becoming exposed and dispersed in the environment, and a Base
Master Plan restriction indicating that ACM is present. The total estimated cost
for implementing this alternative is approximately $90,000.
Alternative 3Cleanup of ACM on Soil Surface and Excavation of Soils Mixed
with ACM
Under this alternative, ACM fragments visible on soil surfaces would be collected
manually, as described under Alternative 2. In areas in which ACM is mixed with
soil beneath the surface (CAOC 4A, north of Building 38; and CAOC 7A, limited
area near the active burn pit), the contaminated soils would be excavated with
conventional construction equipment. The ACM and soils would be stockpiled,
manifested, loaded, transported, and disposed of at a permitted facility. The total
estimated cost for implementing this alternative is approximately $710,000.
Alternative 4Cleanup of ACM on Soil Surface, Partial Excavation, and Partial
Capping
Under this alternative, ACM fragments visible on soil surfaces would be collected
manually, as described under Alternative 2. In the limited area near the active
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bum pit (CAOC 7A), where ACM is mixed with surface soils to a maximum depth
of one foot, the contaminated soils would be excavated with conventional
construction equipment, as in Alternative 3. This alternative differs from
Alternative 3 in that only the central portion of the remedial unit north of Building
38 (CAOC 4A) would be excavated, since the Station has plans to develop this
area. The eastern portion of CAOC 4A would be capped with asphalt. Because
ACM would remain in place in the eastern portion of CAOC 4A, this area would
require long-term maintenance of the cover and a Base Master Plan restriction
indicating that ACM is present. The total estimated cost for implementing this
alternative is approximately $880,000.
2.12.4 CAOCs with Potential Health Risks
The human health risk assessment associated with the OU2 RI indicated that
residential use of CAOCs 1 and 10 had a potential to present an unacceptable level
of carcinogenic risk. In addition, unrestricted use of CAOC 8A has the potential to
pose an unacceptable health risk because the landfill interior has not been fully
characterized. The use of institutional controls for these CAOCs was evaluated in
the FS (U&A, 1996b).
*
2.12.5 Alternatives Considered for Responding to Potential Health Risks at
CAOCs 1,8A, and 10
In accordance with the U.S. EPA Interim Final Guidance for Conducting Remedial
Investigations and Feasibility Studies Under CERCLA (U.S. EPA, 1988), general
response actions (GRAs) are identified as those general classes of actions that can
be taken to manage or control a particular problem at a site. Based on discussions
between U.S. EPA, ADEQ, MCAS Yuma, and the Navy1, two GRAs were selected
for consideration as potentially applicable at CAOCs 1, 8A, and 10.
No Action (included in accordance with CERCLA guidance)
Institutional controls
Alternative 1, No Action: The no action alternative does not present an
unacceptable risk to human health under current use scenarios. However,
unrestricted future uses of the three CAOCs could lead to unacceptable risk levels.
Meeting between representatives of U.S. EPA, ADEQ, MCAS Yuma, the Navy, and U&A held on June 20,
1996 in San Francisco, California.
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Alternative 2, Institutional Controls: The institutional controls would restrict the
land use of CAOC 1 and CAOC 10 to industrial/commercial use and CAOC 8A to
the current use (inactive landfill /surface disposal area). The institutional controls
would be implemented through the Base Master Plan, which would reference the
OU2 ROD. Additions to the Base Master Plan would include a map indicating the
locations of the former disposal areas in CAOC 8A. This would include execution
and recordation of a VEMUR in accordance with and substantially in the form set out
at Arizona Revised Statutes, Section 49-152. The VEMUR would contain language
clarifying that it was executed and recorded by the federal government, or the
appropriate entity of the federal government, "for itself only, and not as a covenant
running with the land". In addition, it would clarify that:
a. The parties agree that no interest in real property on behalf of the State of
Arizona is created either by this VEMUR or by any notice of cancellation of
this VEMUR pursuant to A.R.S. 49-152.
b. The signature of an authorized representative of the Arizona Department of
Environmental Quality (ADEQ) which appears herein acknowledges that the
remediation of the property was conducted in accordance with the provisions
of A.R.S 49-152.
The Base Master Plan would require that any changes in activities in these CAOCs
or land use changes be coordinated through and reviewed by the MCAS Yuma
Environmental Department. Before the land use restrictions are incorporated in
the BMP, the Navy will obtain the approval of the U.S. EPA for the language of
the restrictions and the location in the BMP at which the approved language will
be incorporated. In the event that the Navy plans any future changes in land use
at CAOCs 1, 8A, or 10, the Navy in consultation with U.S. EPA and ADEQ would
re-evaluate the remedy in light of the intended land use. If the change in land use
is not compatible with the remedy, the remedy may be changed pursuant to
CERCLA Sections 120 and 121 and the National Oil and Hazardous Substances
Pollution Contingency Plan (NCP) Section 300.430 (0 (4) (iii) and the ROD may be
amended. If the Navy plans to excess the property to a non-federal entity, it will
notify ADEQ and EPA in advance of the execution of any such transfer. The Navy
will consult with ADEQ and EPA in revisiting existing land use
classifications/restrictions for the CAOC (or, in the alternative, the remedial
action selection) to determine if the foreseeable future land use differs from the
assumptions made at the time the original remedial action decision was made. At
that time, a re-evaluation of the appropriate institutional controls will be
undertaken by the Navy, in consultation xvith ADEQ and EPA. For CAOC 1 or
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CAOC 10, a change in land use from industrial to residential use would require
re-evaluation of the remedy. For CAOC 8A, a change in land use involving any
activities that may require disruption and exposure of the landfill interior would
require re-evaluation of the remedy. At the time of these future activities, further
investigation may be undertaken in order to determine if remediation is required
and if the ROD must be amended.
2.13 Summary of the Comparative Analysis of Alternatives
2.13.1 Introduction
The remedial alternatives developed in the FS were analyzed in detail using the
nine evaluation criteria required by the NCP (Section 300.430 (e) (7)). These
criteria are classified as threshold criteria, primary balancing criteria, and
modifying criteria. Threshold criteria are listed below:
Overall protection of human health and the environment
Compliance with ARARs
Primary balancing criteria are as follows:
9
Long-term effectiveness and permanence;
Reduction of toxicity, mobility, or volume through treatment
Short-term effectiveness
Implementability
Cost
Modifying criteria:
State/support agency acceptance
Community acceptance
The proposed alternatives were evaluated to identify the alternative providing the
best balance among the nine criteria for each CAOC at which remedial actions are
required. Evaluation of the four alternatives for ACM with respect to the nine
criteria are summarized in Section 2.13.3, and the two alternatives for CAOCs that
may present a health risk are similarly evaluated in Section 2.13.4. Note that for
the 12 CAOCs that require no further action, ARARs are not triggered because
remedial action is not required at these CAOCs.
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2.13.2 Applicable or Relevant and Appropriate Requirements
Pursuant to Section 121(d)(l) of CERCLA [42 USC Section 9621(d)], remedial
actions must attain a degree of cleanup that assures protection of human health
and the environment. In addition, remedial actions that leave hazardous
substances, pollutants, or contaminants on site must meet standards,
requirements, limitations, or criteria that are ARARs. Federal ARARs may include
requirements under any federal environmental laws or state requirements
adopted pursuant to a federally-authorized program. State ARARs include
promulgated requirements under state environmental or facility-siting laws that
are more stringent than federal ARARs and that have been identified to the lead
federal agency by the State in a timely manner.
Applicable requirements are those cleanup standards, control standards, and
other substantive environmental protection requirements, criteria, or limitations
promulgated under federal or state law that specifically address a hazardous
substance, pollutant, contaminant, remedial action, location, or other
circumstances at a CERCLA site.
Relevant and appropriate requirements include those that, while not "applicable"
to a hazardous substance, pollutant, contaminant, remedial action, location, or
other circumstances at a CERCLA site, nevertheless address problems or
situations sufficiently similar to those encountered at the CERCLA site to indicate
that their use is well suited to the particular site. A requirement must be both
relevant and appropriate to be designated an ARAR. If no ARAR addresses a
particular situation, or if an ARAR is insufficient to protect human health or the
environment, then nonpromulgated standards, criteria, guidance, and to-be-
considered (TBC) advisories may be used to provide a protective remedy.
On-site response actions may proceed without obtaining permits pursuant to
CERCLA Section 121(e). This permit exemption allows the response action to
proceed in an expeditious manner, free from potential lengthy delays of approval
by administrative bodies. This permit exemption applies to all administrative
requirements, whether or not they are actually styled as "permits." Thus,
administrative requirements cannot be ARARs.
Off-site remedies must comply with all applicable laws and must obtain all
necessary permits and fulfill all administrative procedures.
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ARARs are identified on a site-specific basis from information about specific
chemicals at the site, specific actions that are being considered as remedies, and
specific features of the site location. There are three categories of ARARs.
Chemical-specific ARARs are numerical values or methodologies that, when
applied to site-specific conditions, result in the establishment of numerical values.
They are used to determine acceptable concentrations of specific hazardous
substances, pollutants, and contaminants in the environment.
Location-specific ARARs are restrictions placed on the concentrations of
hazardous substances or the conduct of activities solely because the site occurs in
a special location, such as a wetland or floodplain.
Action-specific ARARs are technology or activity-based requirements or
limitations on actions taken with respect to hazardous waste. In some cases,
ARARs that may be associated with a particular remedial action (such as closure,
discharge, or land placement) can be characterized as both action-specific ARARs
and chemical-specific ARARs, because they include numerical values for chemical
concentrations.
»
2.13.3 Preferred Alternative for ACM in Soil
The preferred alternative for addressing asbestos at MCAS Yuma is Alternative 3,
cleanup of ACM on soil surface and excavation of soils mixed with ACM. This
alternative meets the nine ranking criteria that the U.S. EPA uses to evaluate
alternatives. The remainder of this section summarizes the performance of the
preferred alternative against the nine evaluation criteria and notes how it
compares to the other alternatives considered. Because the No Action alternative
is not protective of human health and the environment, it is not considered in the
" evaluation.
Overall Protection of Human Health and the Environment
Alternatives 2, 3, and 4 are considered protective of human health and the
environment. The preferred alternative (Alternative 3) provides the best
protection of human health and the environment, since all ACM is removed from
the site.
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Compliance with ARARs
The federal ARARs are summarized below:
Federal Chemical-Specific ARARs for ACM at MCAS Yuma: No federal chemical-
specific ARARs have been identified for ACM at MCAS Yuma OU2.
Federal Location-Specific ARARs for ACM at MCAS Yuma: Federal laws that
were identified by the Navy as potential location-specific ARARs QEG, 1995d)
include the following:
National Historic Preservation Act, 16 USC Section 470-470w-6 [36 CFR Part
800] and the Archeological Resource Protection Act, 16 USC Section 470ii
[36 CFR Part 299]: Scientific, prehistoric, or archaeological artifacts may be
present at MCAS Yuma.
Endangered Species Act, 16 USC 1531 et set}.; and Fish and Wildlife
Coordination Act, 16 USC 661 et seq. [50 CFR Parts 200 and 402, and 33 CFR
Parts 320-330]: With the exception of migratory birds that have been observed
in the airspace above MCAS Yuma, no state or federally listed threatened or
endangered species are currently known to be present at MCAS Yuma.
Migratory Bird Treaty Act of 1972,16 USC 703: Migratory birds have been
observed in the airspace above MCAS Yuma.
ACM waste at MCAS Yuma was disposed of at the land surface. The federal laws
given above do not appear to apply to the remedial action alternatives because the
alternatives are not anticipated to disturb habitats or excavate native soils. In
addition, the Station is not expected to be included in or eligible for the National
Register of Historic Places. A 1997 archeological survey of MCAS Yuma identified
a circa 1940s historic trash site and three isolated occurrences of Native American
Pottery; none of these sites are impacted by remedial activities for OU2. Thus, no
federal location-specific asbestos ARARs pertaining specifically to asbestos or to
the selection of remedial action alternatives have been identified.
Federal Action-Specific ARARs: Federal action-specific ARARs include the
following:
Clean Air Act, National Emission Standard for Hazardous Air Pollutants
(NESHAP) USC 7401 to 7671(q): Asbestos was first designated as a
hazardous air pollutant under the Clean Air Act in 1971. The National
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Emission Standard for Hazardous Air Pollutants (NESHAP) for asbestos
found at 40 CFR Section 61, Subpart M is considered an action-specific ARAR
for the site. ADEQ is the lead agency for asbestos NESHAP compliance. The
requirements listed below are not applicable, because they address asbestos
from operations (i.e., demolition, renovation, fabricating, and spraying) that
are not related to the proposed remedial action. The substantive requirements
are considered relevant and appropriate, however, because they address
problems similar to those encountered at CERCLA sites.
Section 61.145: Applicability, Notification Requirements, and Asbestos
Emission Control: NESHAP applies to demolition or renovation of
facilities with ACM. Remediation of ACM at MCAS Yuma is neither a
renovation nor demolition operation. Notification (Section 61.145(b)) is an
administrative requirement that is not applicable to CERCLA actions.
However, procedures for asbestos emission control (Section 61.145(c)) are
substantive requirements that are considered relevant and appropriate.
Section 61.150: Standards for Waste Disposal for Manufacturing,
Fabricating, Demolition, Renovation and Spraying Operations:
Procedures for ACM waste handling, transportation, and disposal are
considered relevant and appropriate. Both the administrative and
substantive requirements of this section are considered ARARs because
transportation and disposal will occur off site.
The state ARARs are summarized below:
State Chemical-Specific ARARs for ACM at MCAS Vuma: No state chemical-
specific ARARs have been identified for ACM at MCAS Yuma OU2.
State Location-Specific ARARs for ACM at MCAS Yuma: The following state law
was identified by the Navy as a potential location-specific ARAR (JEG, 1995d):
Arizona Revised Statutes, Title 41: State Government; Chapter 4.1, History,
Archaeology and State Emblems; Article 4: Archaeological Discoveries
[ARS 41-844A]: Archaeological, palaeontological, or historical features may be
discovered at MCAS Yuma during the course of surveys, excavations, or
construction that occur during a remedial action.
ACM waste at MCAS Yuma was disposed of at the land surface. The state law
identified in this section does not appear to apply to the remedial action
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alternatives. MCAS Yuma is currently consulting with the Arizona historic
preservation office. Although a final determination has not yet been made, the
Station is not expected to be included in or eligible for the National Register of
Historic Places. A 1997 archeological survey of MCAS Yuma identified a circa
1940s historic trash site and three isolated occurrences of Native American
Pottery; none of these sites are impacted by remedial activities for OU2. Thus, no
state location-specific asbestos ARARs pertaining specifically to asbestos or to the
selection of remedial action alternatives have been identified.
State Action-Specific ARARs: ADEQ is the lead agency for implementing
NESHAP, which was identified as an ARAR under the discussions of federal
ARARs.
Other Criteria: As discussed above, if no ARAR addresses a particular situation,
or if an ARAR is insufficient to protect human health or the environment, then
nonpromulgated standards, criteria, guidance, and to-be-considered (TBC)
advisories may be used to provide a protective remedy. Other criteria that were
evaluated as potential TBC include the following:
Chief of Naval Operations Instruction (OPNAVINST) 5100.23D, Chapter 17:
The Navy manual provides guidance for controlling or eliminating the
exposure of Navy personnel to asbestos during the use, removal, and disposal
of ACM.
These provisions apply primarily to building structures and facilities and are
guidance only. Since compliance with the NESHAP requirements discussed
above under federal action-specific ARARs and with federal OSHA are
considered sufficient to provide a remedy that is protective of human health and
the environment, the Navy manual is not considered TBC.
Summary of Compliance of with ARARs: Alternatives 2, 3, and 4 are in
compliance with ARARs. A brief summary of the ARARs applicable to the
remediation of ACM contamination at OU2 is given in Table 2-6.
Long-Term Effectiveness and Permanence
Alternatives 3 and 4 provide adequate long-term effectiveness and permanence.
For Alternative 2, in areas where ACM is mixed with subsurface soil, this
alternative is not effective for several reasons:
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Wind and water erosion may remove surface soils, exposing the ACM
fragments mixed with subsurface soils. If ACM become uncovered, additional
cleanup would be required.
The Station would have to place a Base Master Plan restriction indicating that
ACM is present in these areas. Future development may be limited.
Reduction ofToxicity, Mobility, or Volume by Treatment
This criterion is not applicable because none of the alternatives reduce toxicity,
mobility, or volume through treatment.
Short-Term Effectiveness
There may be minimal short-term health and safety risks to nearby workers from
dust emissions during remedial actions. Overall, Alternatives 2, 3, and 4 are
considered effective in the short term for the following reasons:
Controls, such as dust control and air monitoring, would be implemented to
minimize environmental impacts.
Workers would be adequately protected during the remedial action by
compliance with Occupational Safety and Health Administration (OSHA)
requirements.
Can be implemented within a few weeks.
Implementability
There are no technical, administrative, or availability of services and materials
concerns regarding the implementability of the remedial alternatives. Loading
and transportation of soil and ACM debris are widely used and can be
accomplished using well established, conventional construction techniques and
equipment.
Cost
Alternatives 3 and 4 are considered the most protective of human health and the
environment and have the highest long-term effectiveness. The preferred
alternative, Alternative 3, is more cost effective ($710,000) than Alternative 4
($880,000).
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State Acceptance
ADEQ agrees with the preferred alternative (Alternative 3).
Community Acceptance
Based on public input on the Proposed Plan (see Section 3.3) the preferred
alternative is acceptable to the community (Alternative 3).
Based on U.S. EPA evaluation criteria, the rationale for selecting Alternative 3 as
the preferred alternative is as follows:
It provides long-term protection of human health and the environment.
It does not require long-term operation and maintenance.
It allows unrestricted future Station use.
It is acceptable to the Navy, regulatory agencies, and the community.
2.13.4 Preferred Alternative for Responding to Potential Health Risks at
CAOCs 1,8A and 10
The preferred alternative for addressing potential health risks at CAOCs 1, 8A,
* '
and 10 at MCAS Yuma is Alternative 2, institutional controls. This alternative
meets the nine ranking criteria that the U.S. EPA uses to evaluate alternatives. The
remainder of this section summarizes the performance of the preferred alternative
against the nine evaluation criteria and notes how it compares to the No Action
alternative.
Overall Protection of Human Health and the Environment
Alternatives 1 and 2 are considered protective of human health and the
environment under current use scenarios for CAOCs 1, 8A, and 10. The preferred
alternative (Alternative 2) provides the best protection of human health and the
environment, since risk would be managed for any future changes in land use
scenarios at these CAOCs.
Compliance with ARARs
Compliance with Federal ARARs: Federal ARARs have not been identified for
PAHs in soils at CAOC 1 and CAOC 10 or PCBs in soils at CAOC 8A.
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Compliance with State Location- and Action-Specific ARARs: State location- and
action-specific ARARs have not been identified for PAHs in soils at CAOC 1 and
CAOC 10 or PCBs in soils at CAOC 8A.
Compliance with State Chemical-Specific ARARs:
Under the authority of Arizona Revised Statutes Section 49-151 and Section
49-152, ADEQ has established Department-wide standards applicable to soil
remediation activities. The Amended Soil Remediation Rules were adopted in
Arizona Administrative Code (AAC) Title 18, Chapter 7, Article 2, Interim Soil
Remediation Standards (Sections R18-7-201 through R18-7-209) in 1996. These
regulations are not considered "applicable", since remedial actions are being
conducted pursuant to federal law (i.e., CERCLA), rather than under one of the
State regulatory programs listed in AAC, Title 18, Section R18-7-202.A. Nor is the
Marine Corps requesting a "close-out document", as described in R18-7-202.B, for
a cleanup under State law. State concurrence is being sought in the remedy
selected under federal law. However, the Marine Corps has determined certain
substantive requirements of AAC, Title 18, Chapter 7, Article 2 to be relevant and
appropriate to the soil remediation activities described in this ROD.
f
The regulations allow soil remediation activities that attain one of three standards
(Section R18-7-203): 1) remediation to background levels; 2) remediation to the
Health Based Guidance Levels (HBGLs) presented in Appendix A of Title 18,
Chapter 7, Article 2; or 3) remediation to levels derived from a site-specific risk
assessment. HBGL values for the PAHs and PCBs detected at CAOCs 1, 8A, and
10 are presented in Table 2-8.
Other Criteria: As discussed above, if no ARAR addresses a particular situation,
or if an ARAR is insufficient to protect human health or the environment, then
nonpromulgated standards, criteria, guidance, and to-be-considered (TBC)
advisories may be used to provide a protective remedy. Other criteria that were
evaluated as potential TBC include the following:
U.S. EPA Guidance USEPA/540/G-90/007: This guidance describes the
recommended approach for evaluating and remediating sites with PCB
contamination.
CAOC 8A was the only CAOC at which PCB concentrations were higher than are
acceptable for unrestricted, residential land use. Since a human health risk
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assessment has been performed for current land use at CAOC 8A, Alternative 2 is
considered to provide a remedy at CAOC 8A that is protective of human health
and the environment. Therefore, the EPA guidance is not considered TBC.
Summary of Compliance with ARARs: Alternative 2 is in compliance with
ARARs. A brief summary of the ARARs applicable to CAOCs 1, 8A, and 10 is
given in Table 2-7.
Long-Term Effectiveness and Permanence
Alternative 2 provides adequate long-term effectiveness and permanence.
Alternative 1 is not as effective because changes in land use could result in
potentially unacceptable risks to human health.
Reduction ofToxicity, Mobility, or Volume by Treatment
This criterion is not applicable because none of the alternatives reduce toxicity,
mobility, or volume through treatment.
Short-Term Effectiveness
Since the'human health risk is acceptable for current land uses at CAOCs 1, 8A,
and 10, both alternatives are considered effective in the short term.
Implementability
There are no technical or availability of services and materials concerns regarding
the implementability of a No-Action alternative. However, the administrative
implementability may be an obstacle. It is unlikely that ADEQ and U.S. EPA
would accept Alternative 1, because it does not reduce the potential risk to human
health in the event of land use changes. There are no barriers to implementing
Alternative 2, Institutional Controls.
Cost
There are no costs associated with Alternative!. For Alternative 2, there would be
a small cost associated with the proposed addition to the Base Master Plan. In the
future, the language added to the Base Master Plan could incur costs related to
future soil investigation, revised risk assessments, and possible remedial activities.
These potential future costs cannot be estimated at the present time. However, the
activities associated with these costs would likely result only after the ROD has
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been amended; thus, the cost estimates would be part of the amended ROD and
not necessarily part of the present ROD.
State Acceptance
ADEQ agrees with the preferred alternative (Alternative 2).
Community Acceptance
Based on public input on the Proposed Plan (see Section 3.3) the preferred
alternative is acceptable to the community (Alternative 2).
Based on U.S. EPA evaluation criteria, the rationale for selecting Alternative 2 as
the preferred alternative is as follows:
It provides long-term monitoring of land uses to ensure that any future
changes in land use would not result in unacceptable risks to human health.
It is acceptable to the Navy, regulatory agencies, and the community.
2.14 The Selected Remedies
2.14.1 Selected Remedy for ACM in Soils
Under the selected alternative, Alternative 3 (Cleanup of ACM on Soil Surface and
Excavation of Soils Mixed with ACM), ACM fragments visible on soil surfaces
will be collected at the Radar Hill area of CAOC 4B; the bum pit area in CAOC
7A; the ACM piles in the area "south of CALA" (CAOC 7B); and the floor tiles in
CAOC 9. In areas in which ACM is mixed with soil beneath the surface (CAOC
4A, north of Building 38; and CAOC 7A, limited area near the active burn pit), the
contaminated soils will be excavated with conventional construction equipment.
Table 2-9 summarizes the parameters used in the soil volume estimates for the
two areas in which ACM is mixed with subsurface soil.
During excavation, air monitoring stations will be established up and downwind
of the site to evaluate potential health risks resulting from dust and asbestos
exposure during excavation. Air samples will be collected and analyzed off site
for total particulate and asbestos when on site wind velocities exceed a threshold
level that could potentially transport dust off site. During excavation, the soil will
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be watered to minimize dust generation. The bottom and sidewalls of the
excavation area will be inspected for the presence of ACM fragments. Remaining
soils will be compacted and graded to drain. The ACM and soils will be
stockpiled, manifested, loaded, transported, and disposed of at a state and
federally permitted facility, Copper Mountain Landfill Facility, in Wellton,
Arizona.
The total estimated cost developed for this alternative is approximately $710,000.
Capital costs include excavation, transportation and disposal, and site restorations
costs. There is no cost for O&M for this alternative because groundwater
monitoring is not required and there are no remedial systems to operate. Tables 2-
10 and 2-11 provide a detailed cost estimate.
2.14.2 Selected Remedy for Potential Health Risks at CAOCs 1,8A, and 10
Under the selected alternative, Alternative 2, the following institutional controls
will be implemented through additions to the Base Master Plan:
CAOC 1 and 10: In order to control the potential risk from exposure to PAHs
in soils, the institutional controls will restrict the land use of CAOC 1 and
CAOC 10 to industrial/commercial use. A change in land use from industrial
to residential use will require re-evaluation of the remedy. The institutional
controls will be implemented through the Base Master Plan, which will
reference the OU2 ROD. The Base Master Plan will require that any changes
in land use or activities at CAOC 1 or CAOC 10 be coordinated through and
reviewed by the MCAS Yuma Environmental Department. The locations of
the PAH detections will also be documented in the Base Master Plan.
CAOC 8A: In order to control the potential risk from the exposure to the
landfill interior, institutional controls will restrict the land use of CAOC 8A to
the current use. A change in land use at CAOC 8A involving any activities
that may disrupt and expose the landfill interior will require re-evaluation of
the remedy. The institutional controls will be implemented through the Base
Master Plan, which will reference the OU2 ROD. The Base Master Plan will
require that any changes in activities or land use at CAOC 8A be coordinated
through and reviewed by the MCAS Yuma Environmental Department. The
locations of the former disposal areas and the locations of the PCB detections
will also be documented in the Base Master Plan.
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Before the land use restrictions are incorporated in the BMP, the Navy will obtain
the approval of the U.S. EPA for the language of the restrictions and the location
in the BMP at which the approved language will be incorporated.
This would include execution and recordation of a VEMUR in accordance with and
substantially in the form set out at Arizona Revised Statutes, Section 49-152. The
VEMUR would contain language clarifying that it was executed and recorded by the
federal government, or the appropriate entity of the federal government, "for itself
only, and not as a covenant running with the land". In addition, it would clarify that:
a. The parties agree that no interest in real property on behalf of the State of
Arizona is created either by this VEMUR or by any notice of cancellation of
this VEMUR pursuant to A.R.S. 49-152.
b. The signature of an authorized representative of the Arizona Department of
Environmental Quality (ADEQ) which appears herein acknowledges that the
remediation of the property was conducted in accordance with the provisions
of A.R.S 49-152.
In the event that the Navy plans any future changes in land use at CAOCs 1, 8A,
or 10, the Navy in consultation with U.S. EPA and ADEQ would re-evaluate the
remedy in light of the intended use changes. For CAOC 1 or CAOC 10, a change
in land use .from industrial use to residential use will require re-evaluation of the
remedy. For CAOC 8A, a change in land use involving any activities that may
disrupt and expose the landfill interior will require re-evaluation of the remedy.
At the time of these future activities, further investigation may be undertaken in
order to determine if remediation is required and if the ROD must be amended. If
the change in land use is not compatible with the remedy, the remedy may be
changed pursuant to CERCLA Sections 120 and 121 and the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP) Section 300.430(f)(4)(iii)
and the ROD may be amended. If the Navy plans to excess the property to a non-
federal entity, it will notify ADEQ and EPA in advance of the execution of any
such transfer. The Navy will consult with ADEQ and EPA in revisiting existing
land use classifications/restrictions for the CAOC (or, in the alternative, the
remedial action selection) to determine if the foreseeable future land use differs
from the assumptions made at the time the original remedial action decision was
made. At that time, a re-evaluation of the appropriate institutional controls will
be undertaken by the Navy, in consultation with ADEQ and EPA.
There are no costs associated with Alternative 1. For Alternative 2, there may be a
small cost associated with the proposed addition to the Base Master Plan. In the
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future, the language added to the master plan could incur costs related to future
soil investigation, revised risk assessments, and possible remedial activities.
These potential future costs cannot be estimated at the present time. However, the
activities associated with these costs would likely result only after the ROD has
been amended; thus, the cost estimates will be part of the amended ROD and not
part of the present ROD.
2.15 Statutory Determinations
2.15.1 Introduction
In accordance with DERP, 10 U.S.C. Sec. 2701, et seq. and Executive Order 12580,
the Department of Defense (DoD) has been delegated the Presidential authority to
respond under CERCLA to releases of hazardous substances, pollutants, and
contaminants whenever a release or threat of release occurs on a DoD installation
or the sole source of the release is from that installation.". In addition, Section 121
of CERCLA establishes several other statutory requirements and preferences.
These specify that when complete, the selected remedial action for a site must
comply with applicable or relevant and appropriate environmental standards
established under federal and state environmental laws unless a statutory waiver
is justified. The selected remedy also must be cost effective and utilize permanent
solutions and alternative treatment technologies or resource recovery technologies
to the maximum extent practicable. Finally, the statute includes a preference for
remedies that permanently and significantly reduce the volume, toxicity, or
mobility of hazardous wastes as their principal element. The following sections
discuss how the selected remedies meet these statutory requirements.
2.15.2 Statutory Determinations for Selected Remedy for ACM in Soils
Protection of Human Health and the Environment
The selected remedy protects human health and the environment by removing
friable asbestos from the surface and subsurface of CAOCs with ACM present.
Compliance with Applicable or Relevant and Appropriate Requirements
The selected remedy of collection of surface ACM, excavation of subsurface ACM,
and off-site disposal of ACM and associated soils will comply with applicable or
relevant and appropriate chemical-, action-, and location- specific requirements
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(ARARs). The ARARs are presented below. The selection process is summarized
in Table 2-12.
Chemical-Specific ARARs for Asbestos
No chemical-specific ARARs were identified for ACM at MCAS Yuma OU2.
Location-Specific ARARs
Federal and state location-specific ARARs identified by the Navy (JEG, 1995d)
include the following:
National Historic Preservation Act, 16 USC Section 470-470w-6 [36 CFR Part
800] and the Archeological Resource Protection Act, 16 USC Section 470ii
136 CFR Part 299]: Scientific, prehistoric, or archaeological artifacts may be
present at MCAS Yuma.
Endangered Species Act, 16 USC 1531 et set}.; and Fish and Wildlife
Coordination Act, 16 USC 661 et seq. [50 CFR Parts 200 and 402, and 33 CFR
Parts 320-330]: With the exception of migratory birds that have been observed
in the airspace above MCAS Yuma, no state or federally listed threatened or
endangered species are currently known to be present at MCAS Yuma.
Migratory Bird Treaty Act of 1972, 16 USC 703: Migratory birds have been
observed in the airspace above MCAS Yuma.
Arizona Revised Statutes, Title 41: State Government; Chapter 4.1, History,
Archaeology and State Emblems; Article 4: Archaeological Discoveries
[ARS 41-844A]: Archaeological, palaeontological, or historical features may be
discovered at MCAS Yuma during the course of surveys, excavations, or
construction that occur during a remedial action.
ACM waste at MCAS Yuma was disposed of at the land surface. The
requirements identified in this section do not appear to apply to the remedial
action alternatives because these alternatives are not anticipated to disturb
habitats or excavate native soils. MCAS Yuma is currently consulting with the
Arizona historic preservation office. Although a final determination has not yet
been made, the Station is not expected to be included in or eligible for the
National Register of Historic Places. A 1997 archeological survey of MCAS Yuma
identified a circa 1940s historic trash site and three isolated occurrences of Native
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American Pottery; none of these sites are impacted by remedial activities for OU2.
Thus, no location-specific ARARs pertaining specifically to asbestos or to the
selection of remedial action alternatives have been identified.
Action-Specific ARARs
Action-specific ARARs include the following:
Clean Air Act, National Emission Standard for Hazardous Air Pollutants
(NESHAP): The National Emission Standard for Hazardous Air Pollutants
(NESHAP) for asbestos found at 40 CFR Section 61, Subpart M is considered an
action-specific ARAR for the site. ADEQ is the lead agency for asbestos NESHAP
compliance. Although the requirements in 40 CFR sections 61.145, 61.150, and
61.154 are not applicable because they address asbestos from operations (i.e.,
demolition, renovation, fabricating, and spraying) that are not related to the
proposed remedial action. The substantive requirements are considered relevant
and appropriate, however, because they address problems similar to those
encountered at CERCLA sites. NESHAP includes the following:
Section 61.145: Applicability, Notification Requirements, and Asbestos
Emission Control: NESHAP applies to demolition or renovation of facilities
with ACM. Remediation of ACM at MCAS Yuma is neither a renovation nor
demolition operation. Notification (Section 61.145(b)) is an administrative
requirement that is not applicable to CERCLA actions. However, procedures
for asbestos emission control (Section 61.145(c)) are substantive requirements
that are considered relevant and appropriate.
Section 61.150: Standards for Waste Disposal for Manufacturing,
Fabricating, Demolition, Renovation and Spraying Operations: Procedures
for ACM waste handling, transportation, and disposal are considered relevant
and appropriate. Both the administrative and substantive requirements of this
section are considered ARARs because transportation and disposal will occur
off-site.
There are no RCRA or state equivalent RCRA requirements that are applicable to
the selected remedy.
UO-06/sak/dr4.doc8/28/97 2-47
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Other Criteria to Be Considered (TBC)
In implementing the selected remedy, U.S. EPA and the State have agreed to
consider procedures that are not legally binding. This category of to-
be-considered (TBC) procedures consists of advisories, criteria, or guidance that
were developed by EPA, other federal agencies, or states that may be useful in
developing CERCLA remedies. Such criteria are used if no ARAR addresses a
particular situation, or if an ARAR is insufficient to protect human health or the
environment. One such criterion has been identified as a potential TBC.
Chief of Naval Operations Instruction (OPNAVINST) 5100.23D, Chapter 17:
The Navy manual provides guidance for controlling or eliminating the
exposure of Navy personnel to asbestos during the use, removal, and disposal
of ACM.
These provisions apply primarily to building structures and facilities and are
guidance only. Since compliance with the NESHAP requirements discussed
above under federal action-specific ARARs and federal OSHA are considered
sufficient to provide a remedy that is protective of human health and the
environment, the Navy manual is not considered TBC.
#
Cost Effectiveness
The selected remedy is cost effective because it has been identified as providing
overall effectiveness proportional to its costs. The estimated cost for removal of
surface and subsurface ACM under the selected remedy, Alternative 3, is
approximately $710,000. The estimated cost for Alternative 4, removal of surface
ACM and capping of subsurface ACM in place at MCAS Yuma, is approximately
$880,000; because ACM would remain in place in the eastern portion of CAOC 4A,
this area would require long-term maintenance of the cover and a Base Master
Plan restriction indicating that ACM is present. Therefore, the selected remedy is
less costly than Alternative 4 and also does not incur future maintenance costs and
land use restrictions. Alternative 2 costs less ($90,000), but does not provide
adequate long-term control of the ACM.
Utilization of Permanent Solutions and Alternative Treatment Technologies to
the Maximum Extent Practicable
The preferred alternative provides a permanent solution because the ACM in OU2
will be removed. Therefore, no long-term monitoring or maintenance will be
180-06/sak/dr4.doc8/28/97 2-48
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required. Alternative treatment technologies or resource recovery technologies
are not relevant to the ACM cleanup and disposal.
The preferred alternative is effective in the short term for the following reasons:
Community impacts: None. The community is not in the immediate vicinity.
Dust control measures, such as spraying soil with water, will be implemented
to minimize environmental impacts. Air monitoring will be conducted to
evaluate potential impacts.
Protection of workers: Loading contaminated soil into trucks for
transportation to a landfill has the potential to have an adverse short-term
impact on the health of construction workers because of dust and asbestos
fibers potentially generated during excavation and loading. These potential
adverse impacts will be minimized through use of dust control measures.
Workers will be adequately protected during remedial activities by
compliance with Occupational Safety and Health Administration (OSHA)
regulations (51 CFR Part 22612 and 29 CFR 1910.120).
Length of remedial action: This alternative can be implemented in
approximately 13 days.
#
There are no technical, administrative, or availability of services and materials
concerns regarding the implementability of this alternative. Soil excavation,
loading, and transportation are widely used and can be accomplished using well
established, conventional construction techniques and equipment. There are no
technical considerations that would prohibit excavating, transporting, and
disposing of the soil at a permitted landfill. U.S. EPA and ADEQ have determined
that this alternative is administratively acceptable. The services and materials
required to implement this alternative are readily available.
In summary, the preferred alternative would minimize the potential risk to
human health and the environment from ACM and complies with ARARs.
Because the preferred alternative complies with ARARs and no ACM will be left
in place, it is has been accepted by the state. Based on public comment on the
alternative, the preferred alternative is acceptable to the community
180-06/sak/dr4.doc8/28/97 2-49
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Preference for Treatment as a Principal Element
This criterion is not applicable because none of the alternatives reduce toxicity,
mobility, or volume through treatment.
2.15.3 Statutory Determinations for Selected Remedy for Potential Health
Risks at CAOCs 1,8A, and 10
Protection of Human Health and the Environment
Potential risks to on-site workers are currently within acceptable ranges.
Compliance with the institutional controls will ensure that future development of
the CAOCs will not result in unacceptable risks.
The institutional controls will restrict the land use of CAOC 1 and CAOC 10 to
industrial/commercial use and CAOC 8A to the current use. The institutional
controls will be implemented through the Base Master Plan, which will reference
the OU2 ROD. Additions to the Base Master Plan will include a map indicating
the locations of the former disposal areas in CAOC 8A. This would include
execution and recordation of a VEMUR in accordance with and substantially in
the form set out at Arizona Revised Statutes, Section 49-152. The VEMUR would
contain language clarifying that it was executed and recorded by the federal
government, or the appropriate entity of the federal government, "for itself only,
and not as a covenant running with the land". In addition, it would clarify that:
a. The parties agree that no interest in real property on behalf of the State of
Arizona is created either by this VEMUR or by any notice of cancellation of
this VEMUR pursuant to A.R.S. 49-152.
b. The signature of an authorized representative of the Arizona Department
of Environmental Quality (ADEQ) which appears herein acknowledges
that the remediation of the property was conducted in accordance with the
provisions of A.R.S 49-152.
The Base Master Plan will require that any changes in activities or land use in
these CAOCs be coordinated through and reviewed by the MCAS Yuma
Environmental Department. Before the land use restrictions are incorporated in
the BMP, the Navy will obtain the approval of the U.S. EPA for the language of
the restrictions and the location in the BMP at which the approved language will
be incorporated. In the event that the Navy plans any future changes in land use
at CAOCs 1,8A, or 10, the Navy in consultation with U.S. EPA and ADEQ would
180-06/sak/dr4.docW/22/97 2-50
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re-evaluate the remedy in light of the intended land use. If the change in land use
is not compatible with the remedy, the remedy may be changed pursuant to
CERCLA Sections 120 and 121 and the National Oil and Hazardous Substances
Pollution Contingency Plan (NCP) Section 300.430 (f) (4) (iii) and the ROD may be
amended.
For CAOC 1 or CAOC 10, a change in land use from industrial to residential use
will require re-evaluation of the remedy. For CAOC 8A, a change in land use
involving any activities that may require disruption and exposure of the landfill
interior will require re-evaluation of the remedy. At the time of these future
activities, further investigation may be undertaken in order to determine if
remediation is required and if the ROD must be amended. If the Navy plans to
excess the property to a non-federal entity, it will notify ADEQ and EPA in
advance of the execution of any such transfer. The Navy will consult with ADEQ
and EPA in revisiting existing land use classifications/restrictions for the CAOC
(or, in the alternative, the remedial action selection) to determine if the foreseeable
future land use differs from the assumptions made at the time the original
remedial action decision was made. At that time, a re-evaluation of the
appropriate institutional controls will be undertaken by the Navy, in consultation
with ADEQ and EPA.
Compliance with Applicable or Relevant and Appropriate Requirements
The ARARs are presented below and the selection process is summarized in Table
2-12.
Compliance with federal ARARs: Federal ARARs have not been identified for
PAHs in soils at CAOC 1 and CAOC 10 and PCBs in soils at CAOC 8A.
Compliance with State Location- and Action-Specific ARARs: State location- and
action-specific ARARs have not been identified for PAHs in soils at CAOC 1 and
CAOC 10 and PCBs in soils at CAOC 8A.
Compliance with State Chemical-Specific ARARs:
Under the authority of Arizona Revised Statutes Section 49-151 and Section 49-
152, ADEQ has established Department-wide standards applicable to soil
remediation activities. The Amended Soil Remediation Rules were adopted in
Arizona Administrative Code Title 18, Chapter 7, Article 2, Interim Soil
Remediation Standards (Sections R18-7-201 through R18-7-209) in 1996. These
HO-06/sak/dr4.docW/22/97 2-51
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regulations are not considered "applicable", since remedial actions are being
conducted pursuant to federal law (i.e., CERCLA) rather than under one of the
State regulatory programs listed in Arizona Administrative Code (AAC), Title 18,
Sec. R18-7-202.A. Nor is the Marine Corps requesting a "close-out document", as
described in R18-7-202.B, for a cleanup under State law. State concurrence is
being sought in the remedy selected under federal law. However, the Marine
Corps has determined certain substantive requirements of AAC, Title 18,
Chapter?, Article 2 to be relevant and appropriate to the soil remediation
activities described in this ROD.
The regulations allow soil remediation activities that attain one of three standards
(Section R18-7-203): 1) remediation to background levels; 2) remediation to the
Health Based Guidance Levels (HBGLs) presented in Appendix A to Title 18,
Chapter 7, Article 2; or 3) remediation to levels derived from a site-specific risk
assessment. HBGL values for the PAHs and PCBs detected at CAOCs 1 and 10 are
presented in Table 2-8.
There are no RCRA or state equivalent RCRA requirements that are applicable to
the selected remedy.
Other Criteria: As discussed above, if no ARAR addresses a particular situation,
or if an ARAR is insufficient to protect human health or the environment, then
nonpromulgated standards, criteria, guidance, and to-be-considered (TBC)
advisories may be used to provide a protective remedy. Other criteria that were
evaluated as potential TBC include the following:
U.S. EPA guidance USEPA/540/G-90/007: This guidance describes the
recommended approach for evaluating and remediating sites with PCB
contamination.
Since a human health risk assessment has been performed for current land use at
CAOC 8A, Alternative 2 is considered to provide a remedy at CAOC 8A that is
protective of human health and the environment. Therefore, the EPA guidance is
not considered TBC.
Summary of Compliance of with ARARs: Alternative 2 is in compliance with
ARARs. A brief summary of the ARARs for CAOCs 1, 8A, and 10, is given in
Table 2-7.
180-06/sak/dr4.docW/22/97 2-52
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Cost Effectiveness
A small cost is associated with the proposed institutional controls. In the future,
the language added to the master plan could incur costs related to future soil
investigation, revised risk assessments, and possible remedial activities. The
selected remedy is cost effective because these future costs will only be incurred if
land uses at the three CAOCs actually are changed in the future.
Utilization of Permanent Solutions and Alternative Treatment Technologies to
the Maximum Extent Practicable
The preferred alternative requires, long-term control of land uses at the three
CAOCs. However, permanent solutions that require no control of land uses
would require extensive soil investigations and, potentially, expensive remedial
activities. Such expenditures are not required to maintain acceptable risk levels
under current use scenarios. Therefore, the selected alternative is more cost
effective than a permanent solution.
Alternative treatment technologies or resource recovery technologies are not
relevant to the potential health risks at CAOCs 1, 8A, and 10.
*
Implementability
There are no technical, administrative, or availability of services and materials
concerns regarding the implementability of the selected alternative. U.S. EPA and
ADEQ have determined that this alternative is administratively acceptable. The
selected alternative is also acceptable to the community.
Preference for Treatment as a Principal Element
This criterion is not applicable because none of the alternatives reduce toxicity,
mobility, or volume through treatment.
2.16 Documentation of Significant Changes
As described in the Responsiveness Summary (Section 3), the Proposed Plan was
released for public comment on March 20,1997 and a public meeting was held on
April 9, 1997. This Proposed Plan identified "no action" as the selected response
action for 12 of the 18 CAOCs in OU2 because these sites do not pose a threat to
human health or the environment. Because of the presence of ACM in three of the
CAOCs in OU2, remedial action is required to protect human health and comply
180-06/sak/dr4.doc8/28/97 2-53
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with regulatory requirements. The selected remedial action consists of the
collection of ACM on soil surfaces and the excavation of soils mixed with ACM.
At two CAOCs, a human health risk assessment indicated that residential land
use could potentially present an unacceptable health risk and at one other CAOC
any change in land use could potentially present an unacceptable health risk; the
selected action for these CAOCs is the inclusion of institutional controls for these
CAOCs in the Base Master Plan. Comments collected over the 30-day public
review period between March 21, 1997 and April 28, 1997 are addressed in
Section 3.3.
Responses to the public comments did not require any changes to this Record of
Decision.
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3 Responsiveness Summary
3.1 Overview
This section provides a summary of the public comments and concerns regarding the
Proposed Plan at MCAS, Yuma. At this time, the Navy has selected the "no further
action" preferred alternative for 12 of the 18 CAOCs in OU2 because these sites do not
pose a threat to human health or the environment. The selected remedial action for
three CAOCs at which ACM were identified in construction debris consists of the
collection of ACM on soil surfaces and the excavation of soils mixed with ACM. At an
additional two CAOCs, a human health risk assessment indicated that residential land
use could potentially present an unacceptable health risk, and at one other CAOC, any
change in land use could potentially present an unacceptable health risk; the selected
action for these CAOCs is the inclusion of institutional controls for these CAOCs in the
Base Master Plan.
3.2 Background on Community Involvement
The Navy has implemented a progressive public relations and involvement program for
environmental activities at MCAS Yuma. A Restoration Advisory Board (RAB),
comprising representatives from the Navy, U.S. EPA, the Arizona Department of
Environmental Quality, and members of the general public, has been established and
meets periodically to involve the public in decisions regarding investigation results,
proposed work, and potential remedial options. The Navy has also presented RI plans
and results at public meetings conducted on January 18 and April 11,1996. Before each
of these public meetings, the Navy distributed over 40 copies of a fact sheet to interested
parties and to the information repositories (Section 2.7). These fact sheets described the
installation restoration program at MCAS Yuma, including a discussion of how the
public could access more information and become more involved in the program. A
synopsis of community relations activities conducted by the Navy is presented in
Appendix B.
The Navy held a public comment period on the OU2 preferred alternative from
March 21 through April 28,1997. Copies of the Proposed Plan were placed in the above
discussed repositories (Section 2.7) and were mailed to the public for review and
180-06/sak/rod-dr4.doc 3-1
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comment. The Proposed Plan also invited readers to a public meeting to discuss the
preferred alternative and voice their concerns. The meeting was held on April 9, 1997,
from 6:00 to 7:20 p.m., in the Yuma County Main Library at 350 South Third Avenue,
Yuma, Arizona. Comments received during the public comment period are addressed
below.
3.3 Summary of Comments Received During Public Comment Period and
Department of the Navy Responses
Four verbal comments were received at the Public Hearing on the Proposed Plan. The
one written comment on the Proposed Plan is included in Appendix B. This written
comment did not require a response.
Public Comment
Mr. John Colvin asked Amanda Stone of the Arizona Department of Environmental
Quality to explain the proposed land use restrictions in greater detail. After Ms. Stone
provided further information on the legal issues, Mr. Colvin asked if such a land use
restriction would also be applicable to the proposed asbestos removal. Mr. Colvin
asked if the use of a land use restriction for asbestos debris sites would save the
estimated $710,000 cost of excavating asbestos, as long as the $90,000 surface cleanup
was performed. Mr. Colvin suggested that if the buried asbestos were left in place, the
cost of removal could be borne be any future private developer of the sites, rather than
by public money.
Response
Amanda Stone, Remedial Project Manager, Arizona Department of Environmental
Quality, answered the question. Ms. Stone explained that a land use restriction at the
asbestos sites would be much more restrictive than the land use restrictions that
maintain the current uses of CAOCs 1, 8A, and 10. Some of the asbestos sites are
currently slated for development by the Navy and any excavation at these sites would
require removal of the buried asbestos. In addition, as long as the asbestos remains in
the ground, there is a potential for accidental breakdown of the asbestos materials and
the resulting release of fibers.
Public Comment
Ms. Maria Lewis commented that removing the asbestos now would probably be
cheaper than waiting till some unspecified date in the future.
180-06/sak/rod-dr4.doc 3-2
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Response
Ms. Stone observed that the cleanup cost for these sites was not bad compared to many
other sites.
Public Comment
Mr. Kevin Shaffer asked why the cleanup was not being paid for by Superfund.
Response
Nadine Spertus, Remedial Project Manager, Southwest Division, Naval Facilities
Engineering Command, answered the question. Ms. Spertus explained that the Marine
Corps and Navy have a separate fund of money called the Environmental Restoration
Navy Account. Superfund was specifically set up for private parties and is intended to
be a revolving fund that is repaid by identified responsible parties.
Public Comment
Ms. Dottie Lofstrom asked if monitoring wells had been used to study the landfill
(CAOC 8A).
#
Response
Rachel Simons, Remedial Project Manager, U.S. Environmental Protection Agency,
Region IX, answered the question. Ms. Simons explained that, although soil samples
were not taken from within the landfill, soil samples were collected from the surface of
the landfill, soil vapor samples were collected from within the landfill, and groundwater
samples were collected from around the perimeter of the landfill.
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4 References
Arizona Department of Environmental Quality (ADEQ), 1992. Human Health-based
Guidance Levels for the Ingestion of Contaminants in Drinking Water and Soil.
Environmental Protection Agency (U.S. EPA), 1989a. Statistical Analysis of Groundwaler
Monitoring Data at RCRA Facilities (Interim Final Guidance).
U.S.J5PA, 1989b. Health Effects Assessment Summary Tables (HEAST), National Library of
Medicine.
U.S. EPA, 1992. Guidance for Data Usability in Risk Assessment (Part A). OSWER 9285.7-
09A. Office of Emergency and Remedial Response. USEPA/540/G-90/008 (Interim
Final).
U.S. EPA, 1994a. Integrated Risk Information System (IRIS) Database.
U.S. EPA, 1994b. Region IX Preliminary Remediation Goals (PRGs) First Half 1994.
Stanford J. Smucker, Ph.D., Regional Toxicologist.
U.S. EPA, 1^94c. Memorandum on the Role of the Baseline Risk Assessment in Superfund
Remedy Selection Decision. OSWER Directive 9355.0-30.
Federal Facilities Agreement (FFA), 1991. Federal Facility Agreement Under CERCLA
Section 120. Signed by U.S. EPA Region 9, State of Arizona, and the U.S. Department
of the Navy.
Jacobs Engineering Group Inc. (JEG), 1994a. Community Relations Plan (Final).
JEG, 1994b. Final Residential Surface Soil Investigation Report (Draft).
JEG, 1994c. Technical Memorandum 3, Human Health Risk-Based Criteria for Decision
Making (Final).
JEG, 1995a. MCAS Yuma, Asbestos Survey Results. Technical Memorandum dated
February 14.
JEG, 1995b. Preliminary Draft Chemical-Specific and Location-Specific Applicable or Relevant
and Appropriate Requirements Analysis Report, MCAS, Yuma, Arizona. Revision 1,
January 3.
JEG, 1996. Final Remedial Investigation Report, MCAS YUMA. March 26.
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Malcolm Pimie, Inc., 1988. Confirmation Study Verification Phase, Naval Facilities
Engineering Command, Southwest Environmental Section, San Diego, California.
Malcolm Pimie, Inc., 1990. Site Inspection Report (Draft).
Steams, Conrad, Schmidt and Landau Associates (Stearns et al.), 1985. Initial Assessment
Study of Marine Corps Air Station, Yuma, Arizona. Prepared for the Naval Energy and
Environmental Support Activity, NEESA 13-077.
Uribe & Associates (U&A), 1996a. Assessment of ACM Contamination at CAOCs 4, 7, and 9
at Marine Corps Air Station Yuma, Arizona, prepared for Southwest Division Naval
Facilities Engineering Command, San Diego, California.
U&A, 1996b. Feasibility Study for Operable Unit 2, Marine Corps Air Station Yuma, Arizona,
prepared for Southwest Division Naval Facilities Engineering Command, San Diego,
California.
U&A, 1996c. Proposed Plan for Operable Unit 2, Marine Corps Air Station Yuma, Arizona,
prepared for Southwest Division Naval Facilities Engineering Command, San Diego,
California.
U&A, 1996d. Report of Soil Sampling Program For Polycylcic Aromatic Hydrocarbons at
CAOC 10 Operable, Unit 2, Marine Corps Air Station Yuma, Arizona, prepared for
Southwest Division Naval Facilities Engineering Command, San Diego, California.
U&A, 1997. Report of Supplemental Soil Sampling Program For Polycylcic Aromatic
Hydrocarbons at CAOC 10 Operable, Unit 2, Marine Corps Air Station Yuma, Arizona,
prepared for Southwest Division Naval Facilities Engineering Command, San Diego,
California.
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5 Abbreviations /Acronyms
AAC
ACM
ADEQ
ADOSH
ARARs
ARS
ASTM
bgs
BTEX
Bureau
CALA
CAOC
CERCLA
CFR
CLP
COPC
COPEC
CPF
cy
DDT
DoD
ea
U.S. EPA
EM
f/cc
FD
FFA
FS
FSP
ft
GPR
HBCL
HE AST
HI
IAS
1R
IRIS
Arizona Administrative Code
Asbestos-Containing Material
Arizona Department of Environmental Quality
Arizona Department of Occupational Safety and Health
Applicable or Relevant and Appropriate Requirements
Arizona Revised Statutes
American Society for Testing and Materials
below ground surface
Benzene, Toluene, Ethylbenzene, and Total Xylenes
U.S. Bureau of Reclamation
Combat Aircraft Loading Apron
CERCLA Area of Concern
Comprehensive Environmental Response, Compensation, and Liability
Act
Code of Federal Regulations
Contract Laboratory Program
Chemical Of Potential Concern
Chemical Of Potential Ecological Concern
Cancer Potency Factor
cubic yard
1,1,1 -trichloro-2,2-bis(4-chlorophenyl)ethane
Department of Defense
each
U.S. Environmental Protection Agency
Electromagnetic (survey)
fibers per cubic centimeter
Field Duplicate
Federal Facilities Agreement
Feasibility Study
Field Sampling Plan
foot
Ground Penetrating Radar
Health-Based Guidance Level
Health Effects Assessment Summary Table
Hazard Index
Initial Assessment Study
Installation Restoration
Integrated Risk Information System
180-06/sak/rod-dr4.doc
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IRP
JEG
kg
LAAMBN
Mag.
MCAS
mg/kg
mg/l
mph
MWWU
NCP
NAVFACENGCOM
Navy
NESHAP
NFESC
NPL
O&M
OSHA
OPNAVINST
OU
PAHs
PA/SI
PCBs
PCE
PEL
ppb
PR
PRG
PR/VSI
PVC
RAB
RBC
RCRA
RfD
RI
Rl/FS
RME
ROD
SARA
sf
SI
Station
svoc
Installation Restoration Program
Jacobs Engineering Group Inc.
kilogram
Light Anti-Aircraft Missile Battalion
Magnetic (survey)
Marine Corps Air Station
milligrams per kilogram
milligrams per liter
miles per hour
Marine Wing Weapons Unit
National Oil and Hazardous Substances Contingency Plan
Naval Facilities Engineering Command
Department of the Navy
National Emission Standards for Hazardous Air Pollutants
Naval Facilities Engineering Services Center (Formerly NEESA)
National Priorities List
Operations and Maintenance
Occupational Health and Safety Administration or Act (1970)
Chief of Naval Operations Instructions
Operable Unit
Polynuclear/Polycyclic Aromatic Hydrocarbons
Preliminary Assessment/Site Inspection
Polychlorinated Biphenyls
Perchloroethene(tetrachloroethene)
Permissible Exposure Limit
parts per billion
Preliminary Review
Preliminary Remediation Goals
Preliminary Review/Visual Site Inspection
Polyvinyl Chloride
Restoration Advisory Board
Risk-Based Criteria
Resource Conservation and Recovery Act
Reference Dose
Remedial Investigation
Remedial Investigation/Feasibility Study
Reasonable Maximum Exposure
Record of Decision
Superfund Amendment and Reauthorization Act
square foot
Site Inspection
Marine Corps Air Station, Yuma
Semivolatile Organic Compound
180-06/sak/rod-dr4.doc
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Southwest Division
TBC
TCA
TCE
TLV
TPH
TRPH
U&A
use
USCA
USDA
USFWS
UST
VEMUR
VOC
VSI
US/1
Southwest Division, Naval Facilities Engineering Command
To Be Considered
1,1,1-Trichloroethane
Trichloroethene (preferred over trichloroethylene)
Threshold Limit Value
Total Petroleum Hydrocarbons
Total Recoverable Petroleum Hydrocarbons
Uribe & Associates
United States Code
United States Code Annotated
United States Department of Agriculture
U.S. Fish and Wildlife Service
Underground Storage Tank
Voluntary Environmental Mitigation Use Restriction
Volatile Organic Compound
Visual Site Inspection
micrograms per liter
J80-06/sak/rod-dr4.doc
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A: Response to
Comments
-------
Appendix A
Response to U.S. Environmental Protection Agency and Arizona
Department of Environmental Quality Comments on the
Draft OU2 Record of Decision
and the
Draft Final OU2 Record of Decision
-------
U.S. EPA Review Comments on the
Draft Record of Decision (ROD) for Operable Unit 2
Marine Corps Air Station, Yuma, Arizona
Report Dated July 31,1996
Comments Dated October 1,1996
General Comments:
EPA Comment
1. CAOC 8A - Southeast Station Landfill
The conclusion that institutional controls are being implemented at CAOC 8A based on
the detection of PAHs and PCBs in the soils is incorrect. Institutional controls are being
implemented at CAOC 8A because the interior of the landfill was not investigated
during the OU2 Remedial Investigation (RI).
The RI was directed at evaluating the exposure for current land use and future capped
conditions. No intrusive sampling was done. Based on the human health risk
assessment, it was concluded that a landfill cap was not required under the current land
use. Since the interior of the landfill was not investigated under the RI, the risk from
exposure to the landfill interior is unknown.
In order to control the potential risk from exposure to the landfill interior, institutional
controls will be implemented to restrict the land use to the current use. Please revise the
report to reflect this comment.
(This is the same comment as General Comment 1 from the Draft Final OU2 Feasibility
Study.)
U&A Response
The following paragraph (or similar language) has been incorporated into Section 1.4 (page 1-3)
and Section 2.10.6 (page 2-23) of the Final Record of Decision:
"CAOC 8A: Intrusive sampling was not conducted at the southeast station landfill during the
RI. Based on the human health risk assessment, it was concluded that a landfill cap was not
required under the current land use. However, since the interior of the landfill was not
investigated during the RI, the risk from exposure to the landfill interior is unknown."
EPA Comment
2. Institutional Controls
The following language should be included in the ROD for CAOCs 1, 8A and 10:
"The institutional controls will restrict the land use of CAOCs 1 and 10 to
industrial/commercial use and CAOC 8A to the current use. The institutional controls
will be implemented through the Base Master Plan (BMP) and the BMP will reference
the OU2 ROD. the BMP will indicated that any activities in these CAOCs or land use
changes must be coordinated through and reviewed by the MCAS Yuma Environmental
Department.
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In the event of any future change in land use, the remedy may need to be re-evaluated
in light of the land use changes. If the change in land use is not compatible with the
remedy, the remedy may be changed pursuant to CERCLA Section 120 and the National
Oil and Hazardous Substances Pollution Contingency Plan (NCP) Section 300.430 (f)
(iii) and the ROD may be amended.
For CAOCs 1 and 10, a change in land use from industrial use to residential use would
require re-evaluation of the remedy. For CAOC 8A, a change in land use involving any
activities which may require disruption and exposure of the landfill interior would
require re-evaluation of the remedy. At the time of these future activities, further
investigation may be undertaken in order to determine if remediation is required and if
the ROD must be amended."
(This is the same comment as General Comment 2 for the Draft Final OU2 Feasibility
Study. The language in the first sentence of the second paragraph has been slightly
modified.)
U&A Response
The requested language (or similar language) has been incorporated into Section 1.5 (page 1-6),
Section 1.6, Section 2.12.5, Section 2.14.2, and Section 2.15.3. In addition, the following
sentence has been included in the text: "If the land is transferred to a non-federal agency, the
Department of the Navy will file a Voluntary Environmental Mitigation Use Restriction
(VEMUR),,indicating that the property has been remediated to less than residential levels and
that the property shall not be used for residential purposes in the future. The VEMUR will be
recorded in accordance with Arizona Revised Statutes Section 49-152, as implemented in
Arizona Administrative Code Sections R18-7-206 (D)(2)(a) and R18-7-207 (A)."
EPA Comment
3. Please propose the language that will be added to the BMP restricting the land use
of CAOCs 1, 8A and 10 and referencing the MCAS YUMA Environmental
Department and the OU2 ROD.
U&A Response
In a discussion between Southwest Division and U&A, it was agreed that the language to be
added to the BMP need not be included in the ROD.'
EPA Comment
4. The rational used for implementing institutional controls at CAOC 10 should be the
same as CAOC 1.
U&A Response
The Record of Decision has been revised to include the same rational for the use of institutional
controls at CAOC 10 as at CAOC 1.
Phone conversation on December 3,1996 between N. Spertus and M. Pound of Southwest
Division and S. Knott of U&A.
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Specific Comments:
EPA Comment
1. Section 1.2, Site Name and Location, page 1-1
The second sentence of this section states, "Yuma Marine Corps Air Station (Station)
was declared a permanent Air Force installation in 1954." From this statement, it
sounds like the Base is still operated by the Air Force. Please add a subsequent sentence
stating when the Marine Corps took over operation of the Base.
U&A Response
The following sentence has been added to Section 1.2
"In January 1959, the Station and its associated range facilities were transferred to the U.S.
Navy."
EPA Comment
2. Section 1.4 Assessment of the Site, page 1-3
CAOC 8A should be deleted from the bullet on the top of this page and identified under
a separate bullet. The bullet should explain that CAOC 8A requires action because the
interior of the landfill has not been fully characterized and therefore, the risk to human
health is unknown (see General Comment 1).
U&A Response
The requested edits have been made (See response to General Comment I).
EPA Comment
3. Section 1.5 Description of the Selected Remedy, page 1-5
Alternative 2 - Additions to the Base Master Plan
Please state in the first paragraph that the locations of the former disposal'areas for
CAOC 8A will be documented in the BMP.
This comment also applies to the first sentence of the last paragraph of Section 1.6,
Statutory Determination, page 1-6.
U&A Response
The requested edits have been made.
EPA Comment
4. Section 2.4 Enforcement and Regulatory History, page 2-4
Please rewrite the third sentence of the second paragraph on this page as follows, "One
to address potential areas of groundwater contamination and soil contamination deeper
than 10 feet below ground surface (OU1)."
U&A Response
The requested edit,has been made.
EPA Comment
5. Section 2.6.8 CAOC 7: Fire School Area, page 2-8
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The text reports CAOC 7 to occupy an area of approximately 0.45 acre. The RI report
describes that the entire area encompasses approximately 40 acres. Please correct.
U&A Response
The requested edit has been made.
EPA Comment
6. Section 2.6.9 CAOC 8: Southeast Station Landfill, page 2-9
The text describes the finding of hydrocarbons, PCBs, solvents, pesticides, and metals in
the shallow soils at CAOC 8. The detection of polynuclear aromatic hydrocarbons
(PAHs) should also be discussed. The term hydrocarbons was earlier defined as fuel-
related chemicals (i.e. TRPH).
U&A Response
The requested edit has been made.
EPA Comment
7. Section 2.6.11 CAOC 10: Ordinance Munitions Disposal Area, page 2-9
The text describes that hydrocarbons and one anomalous elevated lead concentration
have been detected in the shallow soils underlying this area. The text should also
discuss the finding of PAHs in soil.
U&A Response
The requested edit has been made.
EPA Comment
8. Section 2.6.14 CAOC 13: Drain Field Area, page 2-10
The text describes that rinse fluids from filling and mixing equipment for chemical
weapons at the MWWU were disposed at CAOC 13. It is suggested that the text be
expanded to indicate that the chemical weapons were limited to tear gas and napalm.
U&A Response
According to the MCAS Yuma Environmental Department, chemical weapons have not actually
been used at MCAS Yuma (See MCAS Yuma Environmental Department Comment 12). The
text has been revised as follows:
"Liquid rinsates from filling and mixing equipment used for simulated chemical weapons (tear
gas and napalm) at the MWWU were disposed of to a drain field south of former Building
1585."
EPA Comment
9. Section 2.7 Highlights of Community Participation, page 2-12
Please remove the text from the third sentence of this section beginning with, "For
additional information, contact...." through the address for "Rachel Simons". This
information is too much detail for the ROD.
U&A Response
The text has been removed as requested.
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EPA Comment
10. Section 2.8 Scope and Role of Operable Unit 2, page 2-15
In preceding sections, the 18 CAOCs are described in great detail identifying what
contaminants were found in these areas. However in the last paragraph of this section,
13 CAOCs are dismissed as needing no further action with no explanation other than a
reference to the RI. In lieu of the RI reference, please explain briefly why the 13 areas
are no longer considered areas of concern and reference the appropriate supporting
sections in the ROD.
It is also confusing why the 13 CAOCs which are no longer areas of concern are
continually referring to as CAOCs. Please explain that "CAOC" is a term used to
identify a potential hazardous waste site, but a CAOC is not necessarily a site that
requires remediation.
U&A Response
The number of CAOCs that are no longer areas of concern has been reduced to 12 because CAOC
10 has been included in the CAOCs at which institutional controls will be implemented. The
following text has been inserted into Section 2.8:
"The RI investigated 18 CAOCs at which surface or near-surface disposal or releases of wastes
may have occurred. The investigation ofOU2 was limited to an assessment of the risk/hazard
posed by contaminants in the upper 10 feet of soil. No risk to the environment was identified at
the 18 CAOCs (See Section 2.11). Based on the human health risk assessments summarized in
Section 2.10,15 of the 18 CAOCs may safely be used for residential land use, while chemicals
identified at CAOCs 1, 8A, and 10 present acceptable health risks if their current, non-
residential land uses are maintained. Institutional controls will be implemented for CAOCs 1,
8A, and 10 to minimize potential health risks that might be associated with land use changes at
these CAOCs.
ACM, which was not included in the risk assessments because acceptable exposure limits have
not been established for ACM, was identified in three of the 15 CAOCs that were assessed to be
acceptable for residential land use. The ACM at these three CAOCs (4, 7, and 9) is the only
material within OU2for which removal actions are recommended.
No remedial action is recommended for the 12 CAOCs that are acceptable for residential land use
and have no identified ACM. Although these areas do not present human health risks or
ecological risks, they are still be referred to as CAOCs (CERCLA Areas of Concern) in this
document because, although the term "CAOC" is used to identify a potentially hazardous site, a
CAOC is not necessarily a site that requires remediation."
EPA Comment
11. Table 2-2 Analyte Groups and Associated Methods, page 2-17
Please remove this table because it contains too much detail for the ROD.
U&A Response
Table 2-2 has been deleted as requested.
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EPA Comment
12. Section 2.9 Site Characteristics, page 2-18
A detailed description of the RI approach is not required for the ROD. Please remove
the text from "Soil Gas Surveys" through the end of page 2-19
U&A Response
The text has been removed as requested.
EPA Comment
13. Section 2.9.1 CAOC 1: Flight Line, page 2-20
Since the OU2 RI/FS is referenced in the ROD, it is not necessary to summarize detailed
site information and contaminant concentrations. Section 2.6.2 through 2.6.18 provide
sufficient detail for describing the CAOCs. EPA recommends deleting Section 2.9.1
(page 2-20) through Section 2.9.18 (page 2-38).
U&A Response
Section 2.9.1 through Section 2.9.18 have been deleted as requested. The final paragraphs of
these sections, which briefly summarize the findings of the Field Investigation, have been
incorporated into Sections 2.6.1 through 2.6.18.
EPA Comment
14. Table 2-5 Maximum concentration of Pesticides and PCBs Detected as COPCs at 0 to
10 Feet, MCAS Yuma, Operable Unit 2, page 2-23a
The Risk-Based Criteria for Pesticides and PCBs, and the results for CAOCs 1 and 2
appear to be omitted from Table 2-5.
0
U&A Response
The first page of Table 2-5 was accidentally not bound with the Draft Record of Decision. This
error has been corrected. Note that the tables have been moved to the end of the ROD, behind the
Tab labeled "Tables".
EPA Comment
15. Section 2.10.6 Summary of Risks at Individual CAOCs, page 2-43; and Table 2-7
Summary of Risk Assessment Results, MCAS Yuma, Operable Unit 2, page 2-44
The text and table report the Residential Scenario Hazard Index and Commercial/
Industrial Hazard Index as incremental values over that contributed by background
metals. This is an inaccurate presentation of nononcer health risk. For substances
which have a threshold of action (non-carcinogens), the background level plus the
concentration of the chemical from site activities might produce a combined exposure
which exceeds the threshold for toxic effects. Subtracting the background levels before
calculating risk could therefore misrepresent the threat to public health associated with
the site-related contamination, resulting in the false conclusion that the site-related
chemicals do not impose a risk of adverse effects on health. The text and table should
summarize the findings of the RI in which the table should summarize the findings of
the RI in which the cumulative noncancer hazard index was evaluated, and if necessary,
a target organ system analysis was performed.
U&A Response
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Based on a discussion on October 10, 1996 between U&A, Southwest Division, and the U.S.
EPA, the contents of Section 2.10.6 have been significantly abridged. The CAOCsfor which the
RI found that there was no significant health risk are not discussed in detail in the revised text of
Section 2.10.6. It was agreed that the ROD would state that the health risks are acceptable for
all CAOCs other than 1, 8A, and 10. Only CAOCs 1, 8A, and 10, at which unrestricted land
use could lead to unacceptable health risks, are discussed in detail in Section 2.10.6. Therefore,
the table and the majority of the text addressed by this comment are not present in the current
draft of the Record of Decision.
EPA Comment
16. Table 2-7 Summary of Risk Assessment Results, page 2-44
Please change the title of the second column for Most Likely Use Scenario to Current
Use Scenario.
The second column titled Risk Assessment Scenario is confusing since both the
residential and industrial scenarios were calculated in the risk assessment. A clearer
title would be Risk Assessment Scenarios within the Accetable Risk Rane
to
Response
Table 2-7 has been deleted from the Record of Decision (See response to Specific Comment 15).
EPA Comment
17. Table 2-7 Summary of Risk Assessment Results, MCAS Yuma, Operable Unit 2,
page 2-44
a) The Residential Scenario Excess Cancer Risk for CAOC 18 should be changed from
<3 E-08 to E-08.
b) The Residential Scenario Hazard Index for CAOC 2 should be changed from zero to
0.08. (Refer to Specific Comment 15).
c) The Residential Scenario Hazard Index for CAOC 9 should be changed from 0.18 to
0.04 (Refer to Specific Comment 15).
U&A Response
Table 2-7 has been deleted from the Record of Decision (See response to Specific Comment 15).
EPA Comment
18. Section 2.10.6.1 CAOC 1: Flight Line, page 2-45
Please rewrite the fourth sentence as follows, "The excess cancer risk for CAOC 1 is
6.48 x 10"5 for the industrial /commercial exposure scenario."
U&A Response
This sentence (now the first of the paragraph) has been edited as requested. Note that this text is
now in revised Section 2.10.6 and that the current draft of the Record of Decision does not
include a Section 2.10.6.1.
EPA Comment
19. Section 2.10.6.8 CAOC 8: Southeast Station Landfill, page 2-46
In the second paragraph, please delete the following statement:
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"...even though the area is almost entirely enclosed by a chain-link fence, access to
vehicles is limited, and the period of time a human receptor is inside the area is
relatively short."
The role of the risk assessment is to evaluate the potential future land uses as well as the
current land use.
U&A Response
The requested edit has been made. Note that this text is now in revised Section 2.10.6 and that
the current draft of the Record of Decision does not include a Section 2.10.6.8.
EPA Comment
20. Section 2.10.6.8 CAOC 8: Southeast Station Landfill, page 2-47
Please delete the last sentence of the second paragraph of this section. This sentence
should be rewritten as'follows:
"Based on the fact that the landfill interior has not been fully characterized and
therefore the human health risks associated with exposure to the landfill interior are not
known, US EPA, ADEQ, and the Navy has made a risk management decision to restrict
the land use of CAOC 8A to the current use and to prohibit any land use that could
potentially disrupt and expose the interior of the landfill."
U&A Response
The requested edit.has been made. Note that this text is now in revised Section 2.10.6 and that
the current draft of the Record of Decision does not include a Section 2.10.6.8.
EPA Comment
21. Section 2.11.6 CAOC 5: Old 2nd LAAMBN Compound, page 2-51
The text states that two metals and two pesticides were found to exceed the soil toxicity
criteria. However, the RI concluded that it is unlikely that vertebrate receptors would
be significantly impacted. The text should indicated that this conclusion was based on
the observations that the COPECs are fairly immobile and do not appear to be related to
site releases.
U&A Response
Based on a discussion on October 10,1996 between U&A, Southwest Division, and the U.S.
EPA, the contents of Section 2.11 have been significantly abridged. The requested language has
been incorporated into a general discussion of the ecological risk at OU2. The discussion of
individual CAOCs has been removed.
EPA Comment
22. Section 2.12.4 CAOCs with Potential Health Risks, page 2-57
Please explain that CAOC 8A poses an unacceptable risk because that landfill interior
has not been fully characterized and not because the residential scenario presents an
unacceptable human health risk (see General Comment 1).
U&A Response
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The text has been amended as requested
EPA Comment
23. Section 2.12.5 Alternatives .Considered for Responding to Potential Health Risks at
CAOC 1 and CAOC 8A, page 2-57
Alternative 2. Additions to the Base Master Plan
Please state in the first paragraph that the locations of the former disposal areas for
CAOC 8A will be documented in the BMP.
U&A Response
The text has been amended as requested
EPA Comment
24. Section 2.13.1 Introduction, page 2-58
It is helpful to add the citation that requires the evaluation of the nine criteria and to
mention the criteria classifications. The following is suggested language for the ROD:
"The remedial alternatives developed in the FS were analyzed in detail using the nine
evaluation criteria required by the NCP (Section 300.430 (e) (7)). These criteria are
classified as threshold criteria, primary balancing criteria, and modifying criteria.
Threshold criteria are:
Overall protection of human health and the environment; and
Compliance with ARARs.
Primary balancing criteria are:
long-term effectiveness and permanence;
reduction of toxicity, mobility, or volume through treatment;
short-term effectiveness;
implementability; and
cost.
Modifying criteria are:
state/support agency acceptance; and
community acceptance."
The resulting strengths and weaknesses of the alternatives were weighted to identify the
alternative providing the best balance among the nine criteria for each landfill site. The
nine criteria are summarized in the following sections."
U&A Response
The suggested text has been incorporated in Section 2.13.1. The final paragraph has been revised
to incorporate references to appropriate discussions of the ARARs for sites with ACM and sites
with Potential Health Risks, as well as to incorporate language recommended in Specific
Comment 25.
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EPA Comment
25. Section 2.13.2 Preferred Alternatives for ACM Soil, page 2-59
Compliance with ARARs
This section should include an explanation of what ARARs are, when they are used, and
what the ARAR categories are. In addition for the 13 sites that require no further action,
a sentence should be added explaining that ARARs will not be triggered at these sites
because they do not require remedial action. Thus, ARARs only apply to those sites
were there will be an action.
The following is suggested language for the ROD:
"Pursuant to Section 121 (d) (1) of CERCLA [42 USC Section 9621 (d)], remedial actions
must attain a degree of cleanup which assures protection of human health and the
environment. Additionally, remedial actions-that leave hazardous substances,
pollutants, or contaminants on site must meet standards, requirements, limitations, or
criteria that are ARARs. Federal ARARs may include requirements under any federal
environmental laws. State ARARs include promulgated requirements under State
environmental or facility-siting laws that are more stringent than federal ARARs and
that have been identified to US EPA by the State in a timely manner.
Applicable requirements are those clean-up standards, control standards, and other
substantive environmental protection requirements, criteria, or limitations promulgated
under federal or State law that specifically address a hazardous substance, pollutant,
contaminant, remedial action, location, or other circumstances at a CERCLA site.
Relevant and appropriate requirements include those that, while not "applicable" to a
hazardous substance, pollutant, contaminant, remedial action, location, or other
circumstances at a CERCLA site, nevertheless address problems or situations
sufficiently similar to those encountered at the CERCLA site to indicate their use is well-
suited to the particular site. A requirement must be both relevant and appropriate to be
designated an ARAR. If no ARAR addresses a particular situation, or if an ARAR is
insufficient to protect human health or the environment, then nonpromulgated
standards, criteria, guidance, and to-be-considered (TBC) advisories may be used to
provide a protective remedy.
On-site response actions may proceed without obtaining permits pursuant to CERCLA
Section 121 (e). This permit exemption allows the response action to proceed in an
expeditious manner, free from potential lengthy delays of approval by administrative
bodies. This permit exemption applies to all administrative requirements, whether or
not they are actually styled as "permits.". Thus, administrative requirements can not be
ARARs.
Off-site remedies must comply with all applicable laws and must obtain all necessary
permits and fulfill all administrative procedures.
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ARARs are identified on a site-specific basis from information about specific chemicals
at the site, specific actions that are being considered as remedies, and specific features of
the site location. There are three categories of ARARs:
Chemical-specific ARARs are numerical values or methodologies which, when applied
to site-specific conditions, result in the establishment of numerical values. They are
used to determine acceptable concentrations of specific hazardous substances,
pollutants, and contaminants in the environment;
Location-specific ARARs are restrictions placed on the concentrations of hazardous
substances or the conduct of activities solely because the site occurs in a special location,
such as a wetland or floodplain; and
Action-specific ARARs are technology or activity-based requirements or limitations on
actions taken with respect to hazardous waste.
The Federal ARARs are summarized below ... The State ARARs are summarized
below..."
Uf-fA Response
The suggested text generally describing ARARs has been incorporated in Section 2.13.2.
ARARs for the remediation of ACM are discussed in Section 2.13.3. ARARS for CAOCs 1, 8A,
and 10 are discussed in Section 2.13.4. The language stating that ARARs are not triggered at
sites that require no further action has been incorporated in the last paragraph of Section 2.13.1.
EPA Comment
25. Section 2.13.3 Preferred Alternative for Responding to Potential Health Risks at
CAOC 1 and CAOG 8A, page 2-62
Compliance with ARARs
It is stated that ARARs have not been identified for PAHs and PCBs in soils at CAOC 1
and CAOC 8A. Please note that last year Arizona passed soil clean-up standards.
Please contact the ADEQ representative for the citation.
U&A Response
Uf-fA has obtained the appropriate citation from ADEQ and the following language has been
inserted in Section 2.13.4
"Under the authority of Arizona Revised Statutes Section 49-151 and Section 49-152, ADEQ
has established Department-wide standards applicable to soil remediation activities. The
Amended Soil Remediation Rules were adopted in Arizona Administrative Code Title 18,
Chapter 7, Article 2, Interim Soil Remediation Standards (Sections R18-7-201 through R18-7-
209) in 1996. These regulations are considered applicable.
The regulations allow soil remediation activities that attain one of three standards (Section R18-
7-203): 1) remediation to background levels; 2) remediation to the Health Based Guidance Levels
(HBGLs) presented in Appendix A of Title 18, Chapter 7, Article 2; or 3) remediation to levels
derived from a site-specific risk assessment."
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EPA Comment
26. Section 2.14.2 Selected Remedy for Potential health Risks at CAOC 1 and CAOC 8A,
page 2-67
In the last paragraph, it is stated, "In the future, the language added to the master plan
could incur costs related to future soil investigations, revised risk assessments, and
possible remedial activities. These potential costs cannot be estimated at the present
time" Please note that the activities mentioned would likely result only after the ROD
has been amended; thus, the cost estimates would be part of the amended ROD and not
necessarily part of this ROD.
U&A Response
The following text has been added to Section 2.13.4 and the last paragraph of Section 2.14.2:
"However, the activities associated with these costs would likely result only after the ROD has
been amended; thus, the cost estimates would be part of the amended ROD and not part of the
present ROD."
EPA Comment
27. Section 2.15.2 Statutory Determination for Selected Remedy for ACM in Soils, page
2-68
Location-Specific ARARs
A string of citations is provided with little or no discussion of how they apply to the
remedy. Please identify which particular sections of the regulations apply to the
remedy and why they apply to the remedy.
U&A Response
The text of Section 2.15.2 has been revised to clarify that the cited regulations and laws do not
apply to the selected remedy.
EPA Comment
28. Section 2.15.2 Statutory Determination for Selected Remedy for ACM in Soils,
page 2-69
Action-Specified ARARs
This section should incorporate the following comments:
a) Sections 61.145 and 61.154: Do these sections include administrative requirements?
Only substantive requirements, not administrative requirements, need to be
complied with for actions that take place on-site. For actions that take place off-site,
both substantive and administrative requirements need to be complied with.
U&A Response
The text has been revised to clarify which of the requirements are administrative and which
of the comments are substantive.
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b) Are there any RCRA requirements or state equivalent RCRA requirements that
would apply to the remedy i.e., fugitive dust limits; treatment, storage or disposal
requirements, etc.?
U&A Response
The text has been revised to clarify that there are no RCRA requirements or state equivalent
RCRA requirements that would apply to the remedy for ACM.
EPA Comment
29. Section 2.15.2 Statutory Determination for Selected Remedy for ACM in Soil, page
2-69
Other Criteria to Be Considered (TBO
Please include a discussion of what a TBC is before listing the TBCs.
U&A Response
The text has been revised as follows:
"In implementing the selected remedy, U.S. EPA and the State have agreed to consider
procedures that are not legally binding. This category of to-be-considered (TBC) procedures
consists of advisories, criteria, or guidance that were developed by EPA, other federal agencies, or
states that may be useful in developing CERCLA remedies. Such criteria are used if no ARAR
addresses a particular situation, or if an ARAR is insufficient to protect human health or the
environment. One such criterion has been identified as a potential TBC."
EPA Comment
30. Section 2.15.2 Statutory Determination for Selected Remedy for ACM in Soil,
page 2-71
In the second paragraph after the bullets, it is stated that "Community acceptance will
be evaluated after the public has commented on the alternative." Please note that the
proposed plan must go through the public comment period before the ROD can be
signed. After the public comment period, community acceptance of the selected remedy
must be documented in the ROD.
U&A Response
The text has been amended to note the proper sequence of public review for the Proposed Plan
and the ROD.
EPA Comment
31. Section 2.15.3 Statutory Determinations for Selected Remedy for Potential Health
Risks at CAOC 1 and CAOC 8A, page 2-71
The first paragraph states, "Compliance with the additional language in the base master
plan would ensure that the future development of the CAOCs would not result in
unacceptable risks." How will the BMP be used so that compliance with the land use
restrictions are enforced?
U&A Response
The text has been revised as follows:
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"The institutional controls would restrict the land use ofCAOC 1 and CAOC 10 to
industrial/commercial use and CAOC 8A to the current use. The institutional controls would be
implemented through the Base Master Plan, which would reference the OU2 ROD. Additions to
the Base Master Plan would include a map indicating the locations of the former disposal areas
in CAOC 8A. The Base Master Plan would require that any changes in activities or land use in
these CAOCs be coordinated through and reviewed by the MCAS Yuma Environmental
Department. In the event that the Navy plans any future changes in land use at CAOC s 1, 8A,
or 10, U.S. EPA would be requested to re-evaluate the remedy in light of the intended land use.
If the change in land use is not compatible with the remedy, the remedy may be changed
pursuant to CERCLA Section 120 and the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP) Section 300.430 (f)(4)(iii) and the ROD may be amended."
EPA Comment
32. Figure 2-1 CAOC 1: Feature and Boring Locations Map 1 through Figure 2-28
CAOC 18: Feature and Boring Location Map
These figures show too much detail. It is recommended that all of the figures be
removed with the exception of the CAOCs where a remedy is being implemented
(CAOC 1, 4, 7, 8A, 9, and 10). The figures of the CAOCs where a remedy is being
implemented should only show the features relevant to the remedy. For example, the
location of the ACM-areas should be shown for CAOC 4 and the location of the former
disposal pits should be shown for CAOC 8A.
Response
The figures have b,een deleted/revised as requested.
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Arizona Department of Environmental Quality (ADEQ) Review
of the Draft Record of Decision for Operable Unit 2
Marine Corps Air Station, Yuma, Arizona
Report Dated July 31,1996
Comments Dated October 1,1996
ADEQ Comment
1. 1.2 Site Name and Location (page 1-1)
A Federal Facility Agreement (FFA) was signed by the U.S. Environmental Protection Agency
(U.S. EPA), the Department of the Navy (Navy), and the Arizona Department of
Environmental Quality (ADEQ) in 1990 to establish a frame work and schedule for
implementing environmental investigations and appropriate remedial actions under the
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).
Comments: The final FFA was signed in January, 1992. Please correct the date at this
location and other locations as appropriate throughout the document.
U&A Response
The text has been corrected as requested.
ADEQ Comment
2. 1.4 Assessment of the Site (page 1-2)
Based on the Rl, U.S. EPA, ADEQ and the Navy agreed that 13 of the CAOCs require no
further action. ."
Comment: The final status of CAOC 10, and other PAH sites, has not yet been
determined. Additional comments may be submitted following review of
recent sampling data.
U&A Response
Based on the August 1996 sampling effort at CAOC 10, the number of sites requiring no further
action is now 12. Institutional controls will be implemented at CAOC 10. In addition, in
response to U.S. EPA's request for further characterization of CAOC 10, the following text has
been added to Section 2.4:
"Investigations performed at MCAS Yuma include the Remedial Investigation/Feasibility Study
(RI/FS) (/EG, 1996), a supplemental sampling program at CAOC 10 (Uribe, 1996b), Federal
Facility Agreement Assessment Program (FFAAP), and underground storage tank
investigations (/EG, 1995b). In addition, further characterization of CAOC 10 will be
performed in 1997."
ADEQ Comment
3. 1.5 Description of the Selected Remedy, Alternative 2-Additions to the Base Master
Plan (page 1-5)
It is expected that this alternative would be acceptable by the state and the community.
Comment: Please provide justification or clarification to this statement.
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U&A Response
The text of Section 1.5 has revised been as follows:
"The state has indicated that Alternative 2 would be acceptable if the substantive requirements of
R18-7-208 and R18-7-209 are met. Based on interaction with the Restoration Advisory Board
(RAB), Alternative 2 is expected to be accepted by the community."
ADEQ Comment
4. 1.6 Statutory Determination (page 1-7)
Comment: Please correct the ADEQ signature block as follows - Russell F. Rhoades,
Director, Arizona Department of Environmental Quality.
U&A Response
The spelling of Russell F. Rhoades' name has been corrected as requested.
ADEQ Comment
5. 2.7 Highlights of Community Participation (page 2-13)
Comment: General information on the community relations program, and contact
names is unnecessary. Please remove this portion.
U&A Response
The text has been removed as requested
ADEQ Comment
6. 2.9 Site Characteristics (page 2-15)
Comment: In general, the information presented in this section should be simplified.
Individual site characteristics should be incorporated in the general site
descriptions presented in section 2.6. Text briefly summarizing significant
sample results should be developed in place of the numerous data tables
currently present in this section.
U&A Response
In conformance with a similar U.S. EPA comment (Specific Comment 13), the text of Sections
2.9.1 through 2.9.18 has been deleted, with the exception of the closing paragraphs that
summarized the significant sample results; these summaries have been incorporated into
Sections 2.6.2 through 2.6.19. However, since U.S. EPA requested corrections to a data
summary table (Specific Comment 14), these tables have been retained in the Record of Decision.
Note that the tables have been moved to the end of the ROD, behind the Tab labeled "Tables".
ADEQ Comment
7. Table 2-2 Analyte Groups and Associated Methods (page 2-17)
Comment: The information provided in this table is not necessary in the ROD.
Please remove the table.
U&A Response
Table 2-2 has been removed as requested.
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ADEQ Comment
8. 2.10.3 Exposure Assessment (page 2-40)
Comment: The state Amended Soil Remediation rules discussed in comment 10 must
be considered in evaluating default exposure parameters described in this
section.
U&A Response
The following text has been added to Section 2.30.3
"Note that the Arizona Health Based Guidance Levels (HBGL) discussed in the ARAR
discussion in Section 2.13.3 are derived using the assumption that incidental ingestion of soil
contaminants is the only significant exposure pathway. Therefore, the RBC values (See Section
2.10.5) are more conservative than the HBGL values. HBGL values are derived by ADEQ for
residential and non-residential scenarios that are analogous to the future use
industrial/commercial and residential scenarios used in developing RBC values. "
ADEQ Comment
9. 2.15 Statutory Determinations (page 2-67)
Comments: A brief description of the ARARs determination process, and a table
presenting all ARARs should be added to this section.
U&A Response
U.S. EPA requested a similar edit for Section 2.13 (Specific Comment 25). See the response to
U.S. EPA Specific Comment 25 for the additional text concerning the ARARs determination
process. The requested table has been incorporated as Table 2-12 of the Final Record of Decision.
ADEQ Comment
10. 2.15.3 Statutory Determinations for Selected Remedy for Potential Health Risks at
CAOC 1 and CAOC 8A (page 2-71)
ARARs have not been identified for PAHs and PCBs in soils at CAOC 1 and CAOC 8A.
Comment: As stated in previous correspondence regarding the OU2 Feasibility Study
(FFU97.021), ADEQ has established Department-wide standards applicable
to soil redemption activities. The amended soil Remediation Rules should
be considered an Applicable, Relevant and Appropriate Requirement
(ARAR). Please make the appropriate changes throughout the ROD.
Response
The text of sections 2.13.3 and 2.15.3 have been amended as follows:
"Under the authority of Arizona Revised Statutes Section 49-151 and Section 49-152, ADEQ
has established Department-wide standards applicable to soil remediation activities. The
Amended Soil Remediation Rules were adopted in Arizona Administrative Code Title 18,
Chapter 7, Article 2, Interim Soil Remediation Standards (Sections R18-7-201 through R18-7-
209) in 1996. These regulations are considered applicable.
The regulations allow soil remediation activities that attain one of three standards (Section R18-
7-203): 1) remediation to background levels; 2) remediation to the Health Based Guidance Levels
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(HBGLs) presented in Appendix A to Title 18, Chapter 7, Article 2; or 3) remediation to levels
derived from a site-specific risk assessment. HBGL values for the PAHs and PCBs detected at
CAOC1, 8A, and 10 are presented in Table 2-7."
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MCAS Yuma Environmental Department Review Comments for
Draft Record of Decision for Operable Unit 2
Marine Corps Air Station, Yuma, Arizona
Report Dated July 31,1996
Comments Dated October, 1996
MCAS Yuma Comment
1. Page 1-1, Section 1.2, first paragraph, a reference to when the Navy/Marine Corps
took control of the Air Station form the Air Force is needed .
U&A Response
The following sentence has been added to Section 1.2
"In January 1959, the Station and its associated range facilities were transferred to the U.S.
Navy."
MCAS Yuma Comment
2. Page 1-1, Section 1.2, second paragraph, OU3 has been identified in the OUl RI
report and should also be identified in this document.
U&A Response
OU3 has not yet been defined. Therefore, OU3 is not discussed in the ROD.
MCAS Yuma Comment
3. Page 1-3, Section 1.4, second bullet item, should identify that the risk is due to the
presence of PAC's and PCB's in the soil. Should also reference that sampling was
not performed in the landfill.
U&A Response
The following paragraph (or similar language) has been incorporated into Section 1.4 (page 1-3)
and Section 2.10.6 (page 2-23) of the Final Record of Decision for Operable Unit 2, MCAS
Yuma, to respond to this comment:
"CAOC 8A: Intrusive sampling was not conducted at the southeast station landfill during the
RI. Based on the human health risk assessment, it was concluded that a landfill cap was not
required under the current land use. However, since the interior of the landfill was not
investigated during the RI, the risk from exposure to the landfill interior is unknown."
The classes of chemicals responsible for the risk (i.e., PAHs and PCBs) are discussed in the
context of the more detailed risk assessment discussions in Section 2.10.6.
MCAS Yuma Comment
4. Page 1-6, Section 1.6, last paragraph on the page, there should be some criteria
placed in the base master plan which is acceptable to EPA/ADEQ to evaluate the
planned activities or land use changes in CAOCs 1 and 8A.
U&A Response
The following text has been incorporated in Section 1.6:
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"The institutional controls would restrict the land use ofCAOC 1 and CAOC 10 to
industrial/commercial use and CAOC 8A to the current use. The institutional controls would be
implemented through the Base Master Plan, which would reference the OU2 ROD. Additions to
the Base Master Plan would include a map indicating the locations of the former disposal areas
in CAOC 8A. The Base Master Plan would require that any changes in activities in these
CAOCs or land use changes be coordinated through and reviewed by the MCAS Yuma
Environmental Department. In the event that the Navy plans any future changes in land use at
CAOCs 1, 8A, or 10, U.S. EPA will be requested to re-evaluate the remedy in light of the
intended land use. If the change in land use is not compatible with the remedy, the remedy may
be changed pursuant to CERCLA Section 120 and the National Oil and Hazardous Substances
Pollution Contingency Plan (NCP) Section 300.430(f)(4)(iii) and the ROD may be amended.
If the land is transferred to a non-federal agency, the Department of the Navy would file a
Voluntary Environmental Mitigation Use Restriction (VEMUR), indicating that the property
has been remediated to less than residential levels and that the property cannot be used for
residential purposes in the future. The VEMUR would be recorded in accordance with Arizona
Revised Statutes Section 49-152, as implemented in Arizona Administrative Code Sections R18-
7-206 (D)(2)(a) and R18-7-207(A).
The rationale for selecting Alternative 2 as the preferred alternative for potential health risks at
CAOCs 1, 8A, and 10 was based on the U.S. EPA criteria listed in Section 1.5. Alternative 2
would be protective of human health and the environment, comply with the State of Arizona and
federal requirements that are legally applicable or relevant and appropriate to the remedial
action, and be cost effective. Because Alternative 2 would result in hazardous substances
remaining on site, a five-year review will apply to this action."
MCAS Yuma Comment
5. Page 1-7, The Marine Corps did not sign the FFA, therefore, the signatures for the
ROD should be of the same agencies as the FFA. However, if necessary. The MCAS
Yuma Commanding Officer's signature would be appropriate.
Response
Southwest Division has determined that the MCAS Commanding Officer, Colonel C. J. Turner,
is to be the Department of the Navy signatory.
MCAS Yuma Comment
6. Page 2-7, Section 2.6.4, CAOC 3 is not completely paved.
U&A Response
The typographical error has been corrected and the text now reads, "The original fenced area of
CAOC 3 covered approximately 0.3 acre ofunpaved land."
MCAS Yuma Comment
7. Page 2-7, Section 2.6.5, no municipal waste was disposed at CAOC 4. Municipal
waste should be reworded to station household waste or words to that effort.
U&A Response
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The text has been revised to clarify that all of the municipal waste was generated at MCAS
Yuma. Note that the term "municipal waste", as used by U.S. EPA, refers to waste streams that
contain household waste. Therefore, "municipal waste" refers to the contents of the waste stream
and does not necessarily imply that the waste originated from a municipality.
MCAS Yuma Comment
8. Page 2-8, Section 2.6.7, same discussion as above concerning municipal waste.
U&A Response
The text has been revised to clarify that all of the municipal waste was generated at the Station.
MCAS Yuma Comment
9. Page 2-8, Section 2.6.9, same discussion as above concerning municipal waste.
U&A Response
The text has been revised to clarify that all of'the'municipal waste was generated at the Station.
MCAS Yuma Comment
10. Page 2-9, Section 2.6.9, Facilities Management Department should be able to
determine a period when the pits were backfilled and housing units were
developed.
U&A Response
The Facilities Management Department was unable to provide the date for the backfilling of the
pits. Therefore, this edit was not made.
MCAS Yuma Comment
11. Page 2-9, Section 2.6.10, DRMO does not use this area as a salvage yard or as an
overflow area.
U&A Response
The text has been edited to remove the statement concerning use of the area as a salvage yard or
as an overflow area.
MCAS Yuma Comment
12. Page 2-10, Section 2.6.14, Chemical weapons were not used at MCAS Yuma. Change
any reference of "chemical weapons" to "simulation of chemical weapons" or words
to that effect.
U&A Response
References to chemical weapons have been deleted from the text.
MCAS Yuma Comment
13. Page 2-12, Section 2.6.19, waste stored in the drums was I.D.W. and PPE (see page
22-1 of the OU2 RI report).
U&A Response
The text has been revised to include the contents of the drums.
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MCAS Yuma Comment
14. Page 2-12, Section 2.7, change the Public Affairs address to the following:
United States Marine Corps
JPAO
Box 99113
Yuma, AZ 85369-9113
(520) 34[9?]l-2275
U&A Response
U.S. EPA and ADEQ requested that Section 2.7 be significantly abridged. The Public Affairs
address is no longer included in the text.
MCAS Yuma Comment
15. Section 2.7, Personal names should not be used because people change jobs.
Position titles and project names should be used in place of names.
U&A Response
EPA and ADEQ requested that Section 2.7 be significantly abridged. The position titles and
project names have been deleted from Section 2.7.
MCAS Yuma Comment
16. Pages 2-21a through 2-24g, photocopies of the table are hard to read. Include a
clean table in the final version of the ROD.
U&A Response
Clean copies are provided.
MCAS Yuma Comment
17. Page 2-26, Section 2.9.1, change RFA Units to FFAAP Units.
U&A Response
At the request of U.S. EPA and ADEQ, this section has been condensed and combined with
Section 2.6.2. The reference to RFA Units was removed when the section was condensed.
MCAS Yuma Comment
18. Page 2-41, Section 2.10.3 "two-year tour of duty" is not an appropriate designation.
Marine Corps policy has changed over the years such that personnel may be
assigned to a duty station up to six years. Please change "two-year tour of duty" to
"duty assignment."
U&A Response
The text has been edited as requested.
MCAS Yuma Comment
19. Page 2-46, Section 2.10.6.5, a glossary should be added so that certain terms, such
as "excess cancer risk" can be defined.
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U&A Response
"Excess cancer risk" is defined in Section 2.10.5. Because Section 2.10 has been greatly abridged
in accordance with a discussion between U.S. EPA, Southwest Division, and U&A on October
10,1996, Section 2.10.6.5 is no longer a component of the ROD. The abridged version of Section
2.10 keeps all references to "excess cancer risk" closer to the definition of the term.
MCAS Yuma Comment
20. Page 2-49, Section 2.11.1, soil screening criteria should be defined.
U&A Response
Based on a discussion between U.S. EPA, Southwest Division, and U&A on October 10,1996,
Section 2.11 has been greatly abridged, and in the present version of the ROD, Section 2.11 is
less than one page of text. The revised text states that; "Soil screening criteria are discussed in
Section 4.16 of the RI Report and derived in Appendix Q of the RI Report (JEG, 1996)." A full
discussion of the screening criteria is beyond the scope of the condensed discussion of
environmental risk that is now included in the ROD.
MCAS Yuma Comment
21. Page 2-50, top two lines are duplicate lines of the previous paragraph.
U&A Response
Text has been corrected.
MCAS Yuma Comment
22. Page 2-50,.Section 2.11.2, soil toxicity criteria should be defined.
U&A Response
The phrase "soil toxicity criteria" was an inconsistent name for "soil screening criteria". The
text of Section 2.11 has been revised to consistently use "soil screening criteria".
MCAS Yuma Comment
23. Page 2-51, Section 2.11.6, this section should repeat the Ecological Risk Assessment
on page 9-5 of the OU2 RI Report.
U&A Response
In accordance with a discussion between U.S. EPA, Southwest Division, and U&A on October
10,1996, Section 2.11.1 through 2.11.20 have been significantly abridged into Section 2.11. The
level of detail on page 9-5 of the OU2 RI Report is no longer appropriate to the abridged Section
2.11
MCAS Yuma Comment
24. Pages 2-64 through 2-66, photocopies of the tables are hard to read. Include clean
tables in the final version of the ROD.
U&A Response
Clean copies are provided.
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MCAS Yuma Comment
25. Page 2-67, Section 2.14.2, both bullet items, how will MCAS Yuma know the risks
involved in changes in land use or activities planned in CAOCs 1 and 8A.
U&A Response
The text has been revised as follows:
"Under the selected alternative, Alternative 2, the following institutional controls would be
implemented through additions to the Base Master Plan:
CAOC1 and 10: In order to control the potential risk from exposure to PAHs in soils, the
institutional controls would restrict the land use of CAOC 1 and CAOC 10 to
industrial/commercial use. A change in land use from industrial to residential use would
require re-evaluation of the remedy. The institutional controls would be implemented
through the Base Master Plan, which would reference the OU2 ROD. The Base Master Plan
would require that any changes in activities or land use at CAOC 1 or CAOC 10 be
coordinated through and reviewed by the MCAS Yuma Environmental Department. The
locations of the PAH detections would also be documented in the Base Master Plan.
CAOC 8A: In order to control the potential risk from the exposure to the landfill interior,
the institutional controls would restrict the land use of CAOC 8A to the current use. A
change in land use at CAOC 8A involving any activities that may disrupt and expose the
landfill interior would require re-evaluation of the remedy. The institutional controls would
be implemented through the Base Master Plan, which would reference the OU2 ROD. The
Base Master Plan would .require that any changes in activities or land use at CAOC 8A be
coordinated through and reviewed by the MCAS Yuma Environmental Department. The
locations of the former disposal areas and the locations of the PCB detections will also be
documented in the Base Master Plan.
In the event that the Navy plans any future changes in land use at CAOC 1, CAOC 8A, or
CAOC 10, EPA would be requested to re-evaluate the remedy in light of the intended use
changes. For CAOC 1 or CAOC 10, a change in land use from industrial use to residential use
would require re-evaluation of the remedy. For CAOC 8A, a change in land use involving any
activities that may disrupt and expose the landfill interior would require re-evaluation of the
remedy. At the time of these future activities, further investigation may be undertaken in order
to determine if remediation is required and if the ROD must be amended. If the change in land
use is not compatible with the remedy, the remedy may be changed pursuant to CERCLA Section
120 and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP) Section
300.430 (f) (4) (Hi) and the ROD may be amended. If the land is transferred to a non-federal
agency, the Department of the Navy would file a Voluntary Environmental Mitigation Use
Restriction (VEMUR). "
MCAS Yuma Comment
26. Page 2-70, Utilization of Permanent Solutions and Alternative Technologies to the
Maximum. Extent Practicable, Community impacts bullet items, what is the impact
on the community in filling Wellton landfill.
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U&A Response
Impacts on filling the Wellton landfill are considered to be out of the scope of the OU2 Feasibility
Study and ROD. Because the Wellton landfill is a permitted facility, general community
impacts of disposal at the facility are expected to be dealt with in the context of the facility's
operating permit.
MCAS Yuma Comment
27. Page 5-2, change RFA to FFAAP.
U&A Response
At U.S. EPA and ADEQ request. Sections 2.9.1 through 2.9.18 and Sections 2.6.1 through
2.6.19 have been condensed and combined into a revised Section 2.6.1 through 2.6.19. The
reference to RFA Units was removed when the sections were condensed. Therefore, "RFA" is no
longer needed in the glossary.
Review Comments from Charles Saltzer, MCAS Yuma for
Draft Record of Decision for Operable Unit 2,
Marine Corps Air Station, Yuma, Arizona
Report Dated July 31, 1996
Comments Dated September 17, 1996
MCAS Yuma Comment
1. Page 1-6 What base master plan would be revised?
*
U&A Response
The text has been revised to emphasize that the institutional controls will be implemented
through the MCAS Yuma Base Master Plan.
MCAS Yuma Comment
2. Page 2-12 Par. 2.7 Lt. Connor is not the Public Affairs Officer. His replacement is 1st.
Lt. Jimenez.
U&A Response
In response to U.S. EPA and ADEQ comments, the text of Section 2.7 has been significantly
abridged. The revised version of 2.7 no longer includes the name of the Public Affairs Officer.
MCAS Yuma Comment
3. Page 2-41 Par. 2.10.3 Exposure Assessment. Is it reasonable to consider re-
development of areas for residential housing? With Yuma County having only
MCAS Yuma as an airport the property would not be ever zoned for residential
development.
Response
Use of residential exposure scenarios is a standard practice in developing risk assessments for
CERCLA sites. In addition, residential development is a reasonable exposure scenario for land at
MCAS Yuma because this scenario includes use of the land for military housing.
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MCAS Yuma Comment
4. Figure 1-1 Location Map The Station boundary is not represented correctly. This
needs to be corrected or someone in the public comment stages could state that not
all areas of the Station were investigated thus the findings are invalid.
U&A Response
Based on a discussion with the MCAS Yuma Environmental Department1, it was decided that
changes to the figure are not warranted. Note that slight inaccuracies in the Station boundary
on Figure 1-1 would not impact the validity of the ROD for OU2, which is only concerned with
the 18 CAOCs identified as the components ofOU2 in previous studies. Prior documents
should have evaluated the full extent of potential contamination on Station property.
Phone conversation between S. Knott of U&A and L. Leake at MCAS Yuma, December 2,
1996.
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EPA Comments on the
Draft Final Record of Decision (ROD) for Operable Unit 2
Marine Corps Air Station, Yuma, Arizona
Report Dated December 20,1996
Comments Dated February 5,1997
General Comments
EPA Comment
1. In EPA's General Comment #3 on the Draft ROD, EPA requested that the Navy
propose language that will be added to the Base Master Plan (BMP) for the institutional
controls at CAOCs 1, 8A and 10. This comment was not adequately addressed. For the
institutional controls at CAOCs 1, 8A and 10, EPA requests the following:
1) The Navy propose the language that will go in the BMP and that EPA
approve the language.
U&A Response
See response to General Comment 1,3).
2) The Navy propose the location where the language will go in BMP and that
EPA approve the location.
U&A Response
The Navy proposes to incorporate the language in Chapter 8, Proposed Land and
Facility Use Plans, of the BMP.
3) the language and location of the language for the BMP be included as an
appendix to the ROD. Alternatively if the language can not be agreed upon
before the ROD is finalized, it must be clearly stated in the ROD that EPA will
approve the language and the location of the language for the BMP.
U&A Response
The following text has been added to Sections 1.5,1.6, 2.12.5,2.14.2 and 2.15.3,
specifying that U.S. EPA will be asked to approve the language and the location of the
language for the BMP.
Before the land use restrictions are incorporated in the BMP, the Navy will obtain
the approval of the U.S. EPA for the language of the restrictions and the location
in the BMP at which the approved language will be incorporated.
EPA Comment
2. In EPA's Specific Comment #31 on the Draft ROD, EPA asked "How will the BMP be
used so that compliance with the land use restrictions are enforced?". This comment
was not adequately addressed. Please provide a brief description of how the BMP is
used for planning purposes. For example, if a construction activity was proposed for
CAOC 10, what process would the Base go through and how would the BMP be used.
This description should be included in the ROD.
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U&A Response
The following excerpt from the MCAS Yuma BMP explains how the BMP is used:
2.0 Introduction
Purpose of the Plan
Guidance for Masterplanning of Naval and Marine Corps installations is
contained in NAVFAC INST 11010.63B, dated October 20,1982. The purpose is to
provide a comprehensive and practical planning process that will support current
and projected mission requirements; improve operational capabilities; and protect
infrastructure investments, resources and the environment. The Plan
demonstrates the commitment of the Navy and the Marine Corps to the
implementation of Department of Defense (DOD) and other federal policies.
The activity master planning process has been designed to ensure the logical,
orderly, and efficient use of land and facility resources, and of military
construction funding. The process includes mechanisms to meet operation, safety
and environmental requirements in the siting and designing of activity projects.
This Masterplan of the Marine Corps Air Station, Yuma, Arizona provides the
Navy and Marine Corps with realistic and orderly development guidance for the
maintenance and further improvement of the installation. It is a decision-making
tool for all levels of command that addresses current issues and provides the
necessary background for planning and review. A preferred development
program and .plan is recommended that has been selected by the Navy and
Marine Corps as the most viable alternative, taking into consideration the
Station's current situation and the planned future of both the Station and its
environment. This Plan has been based upon information provided by the
Station, and these recommendations reflect the evaluations, judgments and
decisions of base personnel.
The Navy will also use Voluntary Environmental Mitigation Use Restrictions (VEMURs)
to restrict the land uses at CAOCs 1,8A, and 10. The following language has been
added to Sections 1.5,1.6, 2.12.5, 2.14.2, and 2.15.3:
The institutional controls would be implemented through the MCAS Yuma Base
Master Plan, which would reference the OU2 ROD. Additions to the Base Master
Plan would include a map indicating the locations of the former disposal areas in
CAOC 8A. In addition, the Navy would execute and record Voluntary
Environmental Mitigation Use Restrictions (VEMURs) in accordance with and
substantially in the form set out at Arizona Revised Statutes, Section 49-152,
where appropriate. Each VEMUR would state that it was executed and recorded
by the federal government "for itself only, and not as a covenant running with the
land". In addition, the VEMUR would state that:
"a. No interest in real property is created by the VEMUR;
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b. The State's approval of any VEMUR notice, or cancellation of same, is to
verify the propriety of the format of the notification, and the accuracy of
any assertion that the cleanup conducted is protective for non-
residential uses."
EPA Comment
3. For information purposes, please provide a copy or relevant sections of the BMP to
EPA.
U&A Response
Copies of relevant sections of the BMP have been included as an attachment to this
response to comments.
Specific Comments
EPA Comment
1 Section 1.5 Description of the Selected Remedy, page 1-6
Alternative 2 - Institutional Controls
Please revise the second sentence on this page as follows, "In the event that the Navy
plans any future changes in the land use at CAOCs 1, 8A, and 10, the Navy in
consultation with U.S. EPA and ADEQ would re-evaluate the remedy in light of the
intended land use." Please also revise the sentence in Sections 1.6, 2.12.5, 2.14.2 and
2.15.3.
U&A Response
The text has been revised as requested.
EPA Comment
2. Section 2.6.11 CAOC 10: Ordnance Munitions Disposal Area, page 2-12
This section must be updated after the additional PAH sampling is completed at CAOC
10. The additional characterization work must be completed before the ROD is
finalized.
Response
As requested, the discussion of sampling at CAOC 10 has been revised using the
additional information obtained in February of 1997. The following text replaces the
last three sentences of Section 2.6.11:
Follow-up sampling programs in August 1996 and February 1997 (U&A, 1996d;
U&A, 1997) demonstrated the presence of PAHs over a wider area than
indicated by the RI. Several sampling locations had total PAH concentrations an
order of magnitude higher than were detected in the RI. Figure 2-10 shows the
total PAH concentrations detected in the August 1996 and February 1997
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samples with the isoconcentration contours defined in the RI Report. Although
the August 1996 and February 1997 data support the presence of elevated PAH
concentrations at the four areas of elevated PAHs identified in the RI Report, the
later data also indicate that elevated PAH concentrations are present at locations
that do not correspond to features identified based on aerial photographs or
geophysical anomalies.
EPA Comment
3. Section 2.10.6 Summary of Risks at individual CAOCs page 2-24
CAOC 10: Ordnance Munitions Disposal Area
Please note that this section will have to be revised after the additional PAH sampling is
completed. Also, it is inconsistent to calculate risk using EPA PRGs when the risk at the
other CAOCs was calculated using RBCs. The reference to PRGs should be discussed
with EPA before it is revised.
U&A Response
As requested, the discussion of risk for CAOC 10 has been revised using the additional
information obtained in February of 1997. The second paragraph of the discussion of
CAOC 10 has been revised as follows:
Based on data from the August, 1996 and February, 1997 field investigations and
the RBCs derived in the RI, the excess cancer risk from PAHs for the residential
exposure scenario was recalculated as 4.6 x 10"1 and for the industrial scenario,
1.5 x 10"*(U&A, 1997). The recalculated industrial excess lifetime cancer risk is at
the upper end of the range of risks that are potentially acceptable for industrial
exposure scenarios.
The RI Risk-Based Criteria (RBCs) used to calculate carcinogenic risk were
developed in 1993 using U.S. EPA exposure factors. U.S. EPA's dermal exposure
factors have since been revised. If the RBCs were calculated with the current
(1996) EPA-approved factors, the RBCs for PAHs would be identical to U.S. EPA
Preliminary Remediation Goals (PRGs). Using the same data and calculating the
risks using PRGs, the industrial and residential excess lifetime cancer risks are
7.0 x 10s and 2.9 x 10"1, respectively. The industrial excess lifetime cancer risk
calculated with PRGs is in the middle of the range of risks that are acceptable for
industrial exposure scenarios.
As discussed in Section 6.3 of the Report of Supplemental Soil Sampling Program for
Poll/Cyclic Aromatic Hydrocarbons at CAOC 10, Operable Unit 2, MCAS Yuma, April 8,1997
(prepared by Uribe & Associates), the most significant difference between the RBC
values and PRG values are the default exposure values for dermal exposure. The RBC
values use the EPA-approved dermal exposure factors that were current in 1993, while
the PRG values used the EPA-approved dermal exposure factors that are presently in
effect. U&A believes that it is appropriate to include the RBC-derived risk values in the
Uribe & Associates/180-06/sak/rodconidf
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discussion of CAOC 10 for the purpose of consistency with the risk values reported for
the other CAOCs, while also reporting the PRG-derived risk numbers to support risk
management decisions.
For the other CAOCs at OU2, use of the RBC values has demonstrated the absence of
significant risk for industrial exposure scenarios. Since the current PRGs include a
smaller exposure component for dermal exposure, revision of the hazard indices and
cancer risks for the other CAOCs would result in risks that were equal to or less than the
risks obtained using the RBC values. Therefore, the use of PRGs to re-calculate the
hazard indices and excess cancer risks for the other CAOCs would not provide
additional protection to human health, since the previous calculations have already
demonstrated that site conditions are sufficiently health protective.
Uribe b Associates/180-06/sak/rodcomdf
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MCAS Yuma Review Comments on the
Draft Final Record of Decision (ROD) for Operable Unit 2
Marine Corps Air Station, Yuma, Arizona
Report Dated December 20,1996
Comments Dated February 24,1997
MCAS Yuma Comment
1. Paragraph 2.6.5, page 2-8, please define municipal wastes or find new term.
U&A Response
The text has been revised as follows:
"This area was used for burning or burying municipal waste (household waste)
generated at MCAS Yuma."
MCAS Yuma Comment
2. Paragraph 2.6.7, page 2-9, please define municipal sewage or find new term.
U&A Response
The text has been revised as follows:
"Treated industrial sewage and municipal sewage (domestic sewage) from MCAS Yuma
MCAS Yuma C6mment
3. Paragraph 2.8, page 2-16, in the last paragraph on the page, remove the word "be"
from the sentence "... they are still be referred.. "
U&A Response
Text has been corrected as requested.
MCAS Yuma Comment
4. Paragraph 2.10.3, page 2-19, were civilian employees included in the exposure
scenarios for current uses at MCAS Yuma for CAOCs that are currently
industrial/commercial.
U&A Response
Civilian employees were included in the future industrial/commercial use scenarios;
the civilian employees are assumed to have a 25-year exposure period in comparison to
the three-year exposure period of the military worker. The text has been revised to
emphasize that risk management decisions were made on the basis of the future use
scenarios because the use of these scenarios was more conservative than the use of the
current use scenarios.
The following paragraph has been inserted following the bullet items on the bottom of
page 2-19:
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"Exposure scenarios were developed for both current and future land uses at MCAS
Yuma. Because the future land use scenarios involve a higher degree of exposure to
chemicals at MCAS Yuma, risk management decisions were made on the basis of the
future use scenarios. Use of the future use scenarios, therefore, provided a more
conservative estimate of risk."
In addition, the following sentence has been inserted after the fourth sentence of the
first complete paragraph on page 2-20.
"Similarly, the industrial exposure scenario for future use includes a 25-year exposure
period, rather than the three-year exposure period for military workers."
MCAS Yuma Comment
5. Paragraph 2.10.6, page 2-24, 2.2 x 10"1 is not within the 10^ to 10* risk range as set
forth by the EPA as being an acceptable risk range. The EPA and ADEQ should be
made aware of this and should concur that the 2.2 x 10"* is an acceptable risk for this
CAOC.
U&A Response
Based on the additional data obtained at CAOC 10 in February 1997, the excess cancer
risk has been revised from 2.2 x 10"* to 1.5 x 10"4. This value is sufficiently close to 1 x 10"1
for the risk management decision proposed in this ROD. EPA and ADEQ are aware of
the calculated risk values.
MCAS Yuma Cpmment
6. Paragraph 2.11, page 2-25, states "No state or federally listed or threatened
endangered species are currently known to be present at MCAS Yuma. No critical
habitats or habitats of endangered species are affected by the COPECs at OU2".
However, Paragraph 2.13.3, page 2-34 states "Federal threatened and endangered
species have been observed on and in the immediate vicinity of MCAS Yuma". These
paragraphs conflict with each other.
U&A Response
The only federal threatened and endangered species that have been observed at MCAS
Yuma are migratory birds that have been observed in the air space above the base.
These species have not been observed in any of the CAOCs in OU2. The text on page
2-25 has been revised as follows:
With the exception of migratory birds that have been observed in the airspace
above MCAS Yuma, no state or federally listed threatened or endangered species
are currently known to be present at MCAS Yuma. No critical habitats or
habitats of endangered species are affected by COPECs at OU2.
The text on page 2-34 has been similarly revised.
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MCAS Yuma Comment
7. Paragraph 1.13.4, page 2-38, states that Alternative 2, Institutional controls is the
preferred alternative for CAOCs 1 and 8A. This paragraph should state that Alternative
2 is also the preferred alternative for CAOC 10.
U&A Response
The text has been revised as requested.
MCAS Yuma Comment
8. Paragraph 2.14.1, page 2-41, "during excavation, soil should be watered to minimize
dust: should be specified.
U&A Response
The text has been revised as requested.
MCAS Yuma Comment
9. Paragraph 2.15, seems to repeat topics that were discussed in previous paragraphs.
Is this paragraph necessary?
\1&A Response
Although Section 2.15 contains some duplication of previous material, it serves a unique
purpose in the required contents of the ROD, as specified in the EPA guidance
document for the preparation of a ROD (OSWER Directive 9335.3-02).
MCAS Yuma Comment
10. Figure 2-8, CAOC 9: Location of ACM Debris, the location of the ACM pile on the
figure is incorrect. The ACM pile is west of the location specified on the map.
U&A Response
Figure 2-8 has been revised as requested.
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Attachment
Excerpts from Marine Corps Airs Station Yuma
Base Master Plan
Uribe & Associatesfl80-06/sak/rodcomdf
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1.0 EXECUTIVE SUMMARY
PURPOSE OF THE PLAN
Activity V.oster Planning of Naval ond Marine Corps installations is directed
by NA"FAC INST I IOI0.63B doted October 22, 1982. The primary planning
instructions for Marine Corps facilities ore contained in MCO PHOOO-I2C.
The purpose is to provide a comprehensive and practical planning process that
will support current and projected mission requirements; improve operational
capabilities; and protect infrastructure investments, resources, and the
environment. The MasterpJan Update of the Marine Corps Air Station Yuma,
Arizona provides the Navy and Marine Corps with realistic and orderly
developrrerit guidance for the maintenance ond further improvement of the
installation. It is a decision-making tool for all levels of command thai
addresses current issues and provides a preferred ond recommended develop-
ment program ond plan.
The Plan will serve as a base document that will continue to be updated
formally within the six-year cycle mandated by NovOl Facilities Engineering
Command (NAVFACENGCOM) in conjunction with the Headquarters Marine
Corps (HOMC). It will be revised informally, os required, by those responsible
for its implementation. The plan has been prepared not only os a facility
scoping and siting guide, but os on information source ond catalyst for base
development beyond its time frame ond as future conditions may require.
FEATURES OF THE MASTERPLAN
MCAS Yumo has expanded significantly in the post decode, both in terms of
increases of base loading ond operations and the importance of its missions.
The Station is now one of the most heavily utilized stateside air facilities in
the U.S. Navy system ond is o crucial element for both air combat training and
operational readiness for the U.S. Marine Corps. This development has
resulted in severe problems for land and facility use planning, however,
because the Station is small in area ond is bounded by civilian aviation uses
ond an aggressive program of development by the community that hove mode
expansion difficult and expensive.
A result of the changes, both of missions and aircraft that hove occurred at
MCAS Yumo, has been a lack of development of a comprehensive land use
plan. This Masterplon offers such a land ond facility use plan for the first
time. The attention of the plan is directed toward the siting of facilities ond
activities within the requirements of the Station's Air Installation Compatible
Use Zone (AICUZ) program and the promotion of greoter coordination among
the functions of the Station. The plan is based on a concept of on ideal station
configuration.
A principal feature of the plan has been the proposal to move ordnance storage
activities from the Main Station to on accessible location near the desert
training facilities. This will enable the Station to meet the requirements of on
l-l
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ossignment as o secondary ordnance stocking point for the Novy and the
combat reodiness ond training missions. Additionally; this will increase safety
on the base, especially in family housing areas, and free a significant amount
of land for housing ond billeting, personnel support, training, and operational
uses.
ACTIVITY DESCRIPTION
MCAS Yumo is located in the southwestern corner of the State of Arizona
near both the California border ond the international border with Mexico. The
Main Station is located on land within the City of Yuma at the southeastern
limits of the city. The airfield utilized by MCAS Yumo for military operations
is a joint-use facility that includes commerciol, general aviation, ond aircraft
manufacturer facilities ond operations under agreement with the Yuma County
Airport Authority.
In addition to the Moin Station, MCAS Yumo maintains or schedules the use of
other nearby--focilities. These include the P-Ml Desert Training Facility,
utilized for Anti-Aircraft Missile training; Auxiliary Airfield-2 that includes a
practice landing (LHA) pod; other Auxiliary Airfields; ond bombing ranges ond
targets in coordination with other military commands. There is a small o'ff-
bose family housing unit within the City of Yuma and recreation facilities ot
nearby Martinez Lake that are also owned by the Station.
MISSION
The primary mission of MCAS Yuma is to maintain ond operate facilities and
provide services ond materials to support operations of a Marine Aircraft
Wing, or -units thereof, ond other activities and units as designated by the
Commandant of the Marine Corps in coordination with the Chief of Naval
Operations. Important tasks assigned to MCAS Yumo include aircraft main'
tenonce, operational training support, and odministrotive and logistic services.
The Station provides ordnance storage, orming, and disposal for tenant and
training activities ond serves os o secondary ordnance stocking point for the
Navy.
Major Tenant groups, squodrons, ond units include:
Marine Aircraft Croup-13 (MAC-13)
Marine Aviation Weapons ond Tactics Squodron One (MAWTS-l)
Marine Wing Weapons Unit One (MWWU-I)
Marine Wing Weapons Unit Three (MWWU-3)
Marine Wing Support Squadron 371 (MWSS-371)
Second Light Anti Aircraft Missile Batolion (2nd LAAM Bn)
Marine Air Control Squadron Seven (MACS-7)
1-2
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MAJOR FINDINGS AND RECOMMENDATIONS
A series of findings hove been generotcd by the Mosterplan process at MCAS
Yumo. These ore the basis for fhe plans ond recommendations included in the
Moslerplan Updote. Significant findings ond recommendations ore summarized
below:
Finding: The primary task ond responsibility of MCAS Yumo during the
period covered by the Mosterplon will be the stand-up of o new tenant
group, MAC-13. This tocticol air group is replacing o Combat Crew
Readiness Training Group (MCCRTG-IO) that has been the major tenant of
the Station, This will involve new aircraft (AV-8B), increases end changes
of base loading, and requirements for new facilities.
Recommendation: Developments ot MCAS Yuma during the planning
period will focus on the installation of MAG-13. This will require
concentration in planning of facilities ot the main station ond the P-llt,
Desert Training Site. New ond improved facilities are required for
MACi-13 and other homeported, tenant, ond rototionof operations ot the
main station. The P-IM Site will be utilized for 2nd LAAM Bn ond
MACS-7. MAG-13 will utilize the facilities these units hove been using ot
the Station.
Finding: There is on acute shortage of developable land on the main
station that presents severe limitations to development. This has resulted
in the past siting of housing, personnel support, ond training activities
within Noise Zone 3 in potential violation of the Station's AlCUZ; siting of
housing and personnel support adjacent to ordnance ESQD areas; and the
siting of family housing units off station.
*
Recommendation: A land use plon is recommended in the Masterplan for
the siting of facilities and activities that will minimize future land use
conflicts.
Recommendations Land to be purchased from the U.S. Bureau of
Reclamation (BUREC) during the Mosterplan period will be utilized for
bachelor housing ond personnel support activities only. Although much of
the land to be acquired is within Noise Zone 3, it is at the outer edge of the
zone and is ideally situated for personnel billeting because of access to the
flight line. Noise attenuation wilt be required for oil construction.
Recommendation: Ordnance storage will be moved from the main station
ond sited in the vicinity of P-l II. This will remove ESOD arcs that arc
restricting the development of significant land parcels on station. The
relocation of ordnance storage will begin with MILCON Project, P-3^6,
during the Mosterplan period.
Recommendation: An Ultimate Land Use Plan is recommended to be
developed beyond the planning period. This should include siting of oil
1-3
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housing and personnel support activities on the main station outside of
Noise Zone 3 and well oway from ESQO or Hazardous Electromagnetic
Radiation Arcs. The Ultimate Land Use Plan should also include the
development of on Outlying Landing Field (OLF) to relieve congestion of
the Station and provide additional training capabilities.
Finding: The present location of ordnance storage requires a permanent
waiver at the south border of the Station, where ESQD arcs cross a public
rood, and special waivers during peak activity times such as Weapons
Training Instruction. These waivers may not be continued, which would
limit ordnance storage capacity and training activities.
Recommendations: The relocation of ordnance storage to the vicinity of
P-lll, beginning with MILCON P-346, will eliminate the need for the
permanent woiver. It will also allow eventual expansion of the Combat
Aircraft Loading Apron (CALA) and relocation of the bomb build-up areas
that will eliminate the need for the special waivers.
Finding: The changes of mission and increases of base loading have
resulted in traffic circulation and parking shortages and problems,
particularly during peak work hours.
Recommendation: A comprehensive traffic circulation study should be
requested of the Military Traffic Management Command, Transportation
Engineering Agency. The study will provide a basis for traffic planning for
the Station for future development.
Recommendation: The circulation network should incorporate the BUREC
property to be acquired during the planning into the Station street system.
Recommendation: A designated parking area system, with decol
designations, is recommended for key areas of the Station. Peak-hour
shuttle bus service, from the parking areas and off-base housing, is
recommended.
Recommendation: The principal road at the flight line will be designated
as a one-way street to relieve congestion and potential traffic hazards
during peak hours.
Recommendation: Sidewalks for pedestrian use should be included in new
street improvements.
Recommendation: Staggered work hours should be adopted to relieve
congestion at peak times.
Recommendation: Supply functions should be consolidated in one area at
the northeast area of the flight line to improve supply and circulation.
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Finding: Public roods odjocent to the Stotion and public roods utilized for
Station activities require improvements to ensure the safety of military
and civilian personnel.
Recommendation: County Road l*» will become a route for regular
transport of ordnance with the relocation of ordnance storage. The rood
should be designated o U.S. Defense Highway. This will provide federal
funds for the county and state for needed improvements to this road.
Recommendation: Coordination should be initiated with the county of
Yuma's Transportation Department and the Arizona Deportment of Trans-
portation for improvements to off station roadways utilized by base
personnel. These should include:
- a designated bicycle path along Avenue 3E
- a pedestrian overhead walkway across Avenue 3E to o planned new
shopping mall; the traffic lights currently in place hove not provided
safe pedestrian crossing areas
noise attenuation structures and sound absorbing materials to be
installed along Avenue 3£ in the vicinity of housing and personnel
support areas
Finding: With the changes of aircraft resulting from new tenant and
transient training operations, the Station's AlCUZ must be updated.
Recommendation: The A1CUZ Update should be undertaken in 1992/93,
one year after the fourth AV-8B squadron has received its full complement
of aircraft.
Finding: The main station currently contains a mixture of building types
and buildings of different ages that lack visual appeal or esthetic qualities
and that thus affect morale and pride in the base.
Recommendation: Future developments and improvements should be made
following the Basic Exterior Architectural guidelines provided in the
Masterplan Update.
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2.0 INTRODUCTION
PURPOSE OF THE PLAN
Guidance for Mosterplanning of Novol and Morinc Corps installations is
contained in NAVFAC INST 11OI0.63B, doted October 20, 1982. The purpose
is to provide o comprehensive and practical planning process thai will support
current ond projected mission requirements; improve operational capabilities;
ond protect infrastructure investments, resources ond the environment. The
Plan demonstrates the commitment of the Navy and the Marine Corps to the
implementation of Deportment of Defense (DOD) ond other federal policies.
The ortivity master planning process has been designed to ensure the logical,
orderly and efficient use of land ond facility resources, and of military
construction program funding. The process includes mechanisms to meet
operation, safety and environmental requirements in the siting ond designing
of activity projects.
This Masterplan of the Marine Corps Air Station, Yuma, Arizona provides the
Novy and Marine Corps with realistic and orderly development guidance for
the maintenance ond further improvement of the installation. It is a decision-
making toot for oil levels of command that addresses current issues and
provides the necessary background for planning ond review. A preferred
development program and plan is recommended that has been selected by the
Novy and Marine Corps as the most viable alternative, taking into considera-
tion the Station's current situation and the planned future of both the Station
ond its environment. This Plan has been based upon information provided by
the Station, ond these recommendations reflect the evaluations, judgments and
decisions of base personnel.
The Plan will serve as a base document that will continue to be updated
formally within the six-year cycle mandated by NAVFAC and solicited by
HQMC. It will be revised informally, as required, by those involved with its
implementation. The Plan has been prepared not only as a facility scoping and
siting guide, bul as an information source and catalyst for bose development
beyond its time frame and as future conditions may require.
PLANNING ASSUMPTIONS
During the preparation of the Masterplon, several assumptions concerning the
planning period were made that directly guided its development. These are
described in the body of this report and include:
MCAS Yuma will continue to exist ot its present location and will
continue to be o vital element in Pacific Fleet air training and
operations.
2-1
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Aircroft operations ot the Air Station wilt reonoin o1 least al the
200,000 per year level and may be increased with planned new tenants
and aircraft.
The Station personnel and aircraft loading will continue to increase to
meet Navy and Marine Corps operations requirements (projected
increase in loading ore provided in the Masterplan report).
MCAS Yumo will continue to host both tenant and transient activities,
and will be required to provide both base and community support
facilities for these activities.
Yuma International Airport will continue to contribute a significant
portion of total airfield operations.
Pressures for development of the City ond County of Yumo, in the
vicinity of the Station, will continue that could jeopardize air opera-
tions and* the " public safety by incompatible development in
inappropriate locations.
Land use controls within determined noise and safety zones around the
airfield will continue to be valid in base and community planning for the
health, safety and welfare of the citizenry.
The effort to ensure the compatibility of development within and
around the Station will continue.
The Masterplon is on update of the 1981 Mosterplon to bring 5t into
conformonce with new DOD ond NAVFAC guidelines, existing conditions, ond
new and projected base loadings. Several major new conditions have come into
existence since the 1981 Plan, including:
*
Changes in missions, aircraft, and operations at the Station.
Increased development and changes in land uses in the vicinity of the
Station.
Increases in civilian ond private air traffic ot the airport, ond in the
airspace utilized by the Station.
Property values in the area hove continued to rise.
MASTER PLANNING PROCESS
Masterplanning for Naval and Marine Corps facilities has been designed as a
dynamic approach to analysis and program design. The process is based upon
the operational requirements of the installation, Navy and Marine Corps
policies and instructions, and is sensitive to man-made and natural constraints,
fiscal resources nnd human concerns.
2-2
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The process wos designed in incrementol steps thot allowed for review at each
stage of development of the Plan. The principal steps were the establishment
of goals and objectives; data collection and analysis;- the development of
planning concept alternatives; development of recommendations (giving
priority to the Military Construction Program, environmental and community
concerns, and fiscal constraints); Command and public review of proposals; and
synthesis of programs, concerns and constraints into the final Plan.
Figure 2-1 provides a flow diagram of planning steps and accomplishments.
PLANNING GOALS
The primary focus of the Wasterplan is to provide a planning document that
will accurately reflect and provide for current and projected mission require-
ments. IT is based on a comprehensive review of current and proposed
development, and mission changes that require revision of the existing
Mosterplan. The recommendations of the Plan provide a basis for the
continuing efficient and orderly development of the Station.
Major planning goals include:
Support of rhe Station's mission through provision of the facilities
needed for future expansion requirements. Priority is given to
functions most directly related to the Station's primary mission.
Document existing conditions data base as a foundation for planning.
Identify and correct deficiencies in existing facilities, focusing on
recommendations that will solve station-wide problems.
Provide guidance for future facility improvements that can be adapted
to changing conditions.
Provide a clear documentation of the planning process that will
facilitate future evaluation and adjustment to changing conditions,
Increase the quality of life for military and civilian personnel of the
Station by improvements in work and living conditions.
Propose the siting of new facilities to take advantage of existing
infrastructure and circulation systems, and to avoid duplication of
facilities and conflicts of use.
Incorporate findings from other studies, as applicable.
Develop a Capital Improvements Plan (CIP) program with appropriate
phasing recommendations to satisfy deficiencies and future
requirements identified in the Masterplan.
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PLANNING STEPS AND ACCOMPLISHMENTS
ESTABLISH GOALS 4
OBJECTIVES
EXISTING
CONOmONS
FAClfTY
REQUIREMENTS DATA
DATA
COUfCTON
REVIEW
PUNNING DATA
BASIC
FAOUTYREOXMREMENT
MAN-MADE AND
NATURAL CONSTRAINTS
DETERMNE PROGRAM
AND DEFICIENCIES
PLANNING
ANALYSIS
RECOMMEND LAND USE
ALTERNATIVES
PROPOSE
PLANNING ACTIONS
MCORPORATE AICUZ
AND ENVIRONMENTAL
ASSESSMENT
SUBMrr EXISTMG CONOmONS
* CONOEPTOEVEIOPMENT
REPOKT
DCVELOPCP
PROGRAM
RNAUZELANO
USE PLAN
SUBMIT PRELIMINARY
DRAFT PLAN
ULTIMATE
DEVELOPMENT PLAN
SUBMIT DRAFT
MASTER PLAN
SUBMfT PRE-FMAL
MASTER PLAN
SUBMIT FINAL
MASTER PLAN
2- 4
FIGURE 2.1
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Develop the Stotion in o way that is compatible wilh the surrounding
community and that recognizes oil noturol orid man-made constraints.
Provide o logical and functional land and facility use plan thai
maximizes the use of land resources, improves installation efficiency,
promotes lond use compatibility both within and in the vicinity of the
Station, and permits future expansion if required.
Comply with all applicable federal and, to the extent possible, state and
local plans and directives that promote public safety, conservation of
energy, and environmental resource protection.
DATA COLLECTION
Two primary dota collection strategies were employed: on-site inspection plus
interviews to provide surveys of existing land use and facilities; and
administration of a comprehensive questionnaire to representatives of Station
deportments and tenants. The questionnaire solicited information on missions
and tasks, building and space utilization, facility requirements, numbers of
authorized on-boord and projected personnel, relationships with on-station ond
off-station organizations ond personnel, condition ond adequacy of location of
structures ond facilities, traffic circulation ond access, utility requirements,
problems and solutions, adverse environmental conditions, ond planned or
proposed future projects and activities.
Data from the questionnaires were classified and expanded by follow-up
interviews with department representatives.
Additional data were obtained concerning local and regional civilian and other
military installation planning. This included o comprehensive historical and
socioeconomic community profile for the City and County of Yuma. An
environmental data base was prepared, including climate, air quality,
geomorphology, scismicity, soils, vegetation, ond wildlife. A cultural resource
assessment included archaeological and historic assessments.
Data collection provided a base for concept development and evaluation at an
early stage of the process, but continued throughout as odditional information
was required ond new concepts explored.
ANALYSIS, PLAN DEVELOPMENT AND EVALUATION
The analysis of data ond the development of conceptual plans were
accomplished with the guidance of NAVFAC INST 110I0.63B. This included
the review of existing and required facilities according to the procedures of
Bosic Facility Requirements ond other planning documents. Facility
deficiencies, surpluses, ond other planning requirements were identified, based
on NAVFAC P-BO planning criteria.
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Wilh these identificotions of facility requirements, solutions and develop-
mental strategies were devised. Land use plans.and recommendations for
development were prepared to remedy deficiencies and meet future
requirements. These recommendations ore based on the priority of mission
requirements and fiscal resources. The resulting Mosterplan of land use end
facility development provides o phased program of facility siting to accom-
modate future growth.
COMMAND REVIEW
A review of development concepts was conducted by the Commending Officer,
MCAS Yuma, and his staff. A pre-draft Plan was then reviewed by Western
Division Novol Facilities Engineering Command (WESTNAVFACENGCOM) and
by MCAS Yurno. The draft Plon was reviewed by MCAS Yumo Commander,
Marine Corps Air Bases Western Area (COMCABWEST), Commandant Marine
Corps (CMC), ond WESTNAVFACENGCOM.
PUBLIC REVIEW
A draft of the final Masterplan was presented to the City of Yumo, Yumo
County, and the State of Arizona for intergovernmental coordination in
compliance with DOD directions and Executive Order 12372.
FINAL PLAN
When approved by WESTNAVFACENGCOM, COMCABWEST, HQMC, ond
CMC, this Final Plan will become the official plan ond future development
guide for the Marine Corps Air Station, Yuma, Arizona.
ORGANIZATION OF THE REPORT
The report of the Masterplon has been prepared in 12 chapters with appendices
to provide supporting documentation. In addition to the Executive Summary
ond this Introduction, these chapters ond appendices ore:
Chapter 3 - Regional Setting
Chapter ^ - Activity Description
Chapter 5 - Installation Description ond Analysis
Chapter & - Development Impacts
Chapter 7 - Concept Development
Chapter 8 - Proposed Land and Facility Use Plans
Chapter 9 - Base Exterior Architecture Plon
Chapter 10 - Capitol Improvements Plon
Chapter 11 - Air Installation Compatible Use Zone (AICUZ) Program
Chapter 12 - Preliminary Environmental Assessment
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Appendix A - Facility Requirements Program (FRP)
Appendix B - Facility Index (Building and Structural Use Summary)
Appendix C - MILCON Program - MCAS Yumo
Appendix O - Acronyms
Appendix E - Hazardous Waste Storage ond Dump Sites
Appendix F - Electromagnetic Hazards Survey for Transmitters at MCAS
Yumo
Appendix C - Airfield Safety Waivers
Appendix H - References
2-7
TOTftL P.613
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B: Community
Relations
-------
Appendix B
Community Relations Activities Conducted by Navy
-------
Community Relations Activities Conducted by Navy.
A public hearing on the Proposed Plan for Operable Unit 2 (OU2) was held on April 9,
1997 at the Yuma County Main Library. The hearing began at 6:00 p.m. and concluded
at 7:20 p.m. The Navy and regulatory agencies were represented by:
Gary Kiger, Clean Project Manager, Jacobs Engineering, 251 S. Lake Avenue,
Pasadena, CA 91101
Larry Leake, IR Program Manager, MCAS Yuma, Building 228, Yuma, Arizona.
Bob Carpenter, Environmental Director, MCAS, Yuma.
Nadine Sperrus, Remedial Project Manager, Southwest Division, Naval Facilities
Engineering Command, 1220 Pacific Highway, San Diego, CA 92132-5181.
Amanda Stone, Remedial Project Manager, Arizona Department of Environmental
Quality, 3033 North Central Avenue, Phoenix, AZ 85012.
Rachel Simons, Remedial Project Manager, U.S. Environmental Protection Agency,
Region IX, 75 Hawthorne Street, San Francisco, CA, 94104-3901.
Mr. Carpenter explained the purpose of the public meeting and summarized the work
to date at OU2. Nadine Spertus explained the CERCLA process, the Department of
Defense Installation Restoration Program, and the contents of the Proposed Plan. Ms.
Spertus explained the planned removal of asbestos-containing material from three of the
CAOCs, as well as the other alternatives that were considered. Ms. Sperrus also
described the three CAOCs at which land use restrictions will be used to manage risk
levels.
Amanda Stone explained that the State agreed in principal with the land use restrictions
for the three CAOCs. Ms. Stone explained that the State and the Navy were still
working out the legal details of implementing the land use restrictions, but that the
details would be worked out before the Record of Decision was signed.
Ms. Spertus closed the presentation part of the Public Meeting by inviting the public to
make verbal or written comments on the Proposed Plan. Because the Proposed Plan
had been distributed later than anticipated, Ms. Spertus announced that the end of the
period for submitting written comments on the Proposed Plan would be extended from
April 21 to April 28,1997.
B-l
-------
Following the presentation, several members of the public asked for further
explanations of the Proposed Plan.
Mr. John Colvin asked Amanda Stone to explain the proposed land use restrictions in
greater detail. After Ms. Stone provided further information on the legal issues, Mr.
Colvin asked if such a land use restriction would also be applicable to the proposed
asbestos removal. Mr. Colvin asked if the use of a land use restriction for asbestos
debris sites would save the estimated $710,000 cost of excavating asbestos, as long as the
$90,000 surface cleanup was performed. Mr. Colvin suggested that if the buried
asbestos were left in place, the cost of removal could be borne by any future private
developer of the sites, rather than by public money. Ms. Stone explained that the
decision to excavate the buried asbestos was a group decision made by many members
of the project team. A land use restriction at the asbestos sites would be much more
restrictive than the land use restrictions that maintain the current uses of CAOCs 1, 8A,
and 10. Some of the asbestos sites are currently slated for development by the Navy and
any excavation at these sites would require removal of the buried asbestos. In addition,
as long as the asbestos remains in the ground, there is a potential for accidental
breakdown of the asbestos materials and the resulting release of fibers.
Ms. Maria Lewis commented that removing the asbestos now would probably be
cheaper than waiting till some unspecified date in the future. Ms. Stone observed that
the cleanup cost for these sites was not bad compared to many other sites.
Mr. Kevin Shaffer asked why the cleanup was not being paid for by Superfund. Ms.
Spertus explained that the Marine Corps and Navy have a separate fund of money
called the Environmental Restoration Navy Account. Superfund was specifically set up
for private parties and is intended to be a revolving fund that is repaid by identified
responsible parties.
Ms. Dottie Lofstrom asked if monitoring wells had been used to study the landfill
(CAOC 8A). Ms. Simons explained that, although soil samples were not taken from
within the landfill, soil samples were collected from the surface of the landfill, soil vapor
samples were collected from within the landfill, and groundwater samples were
collected from around the perimeter of the landfill.
One written comment was received during the comment period. This comment is
included as an attachment to this appendix. The comment consisted of a favorable
evaluation of the Proposed Plan and a question on the feasibility of using alternative
B-2
-------
forms of energy in the pollution management process. The comment did not result in
any changes to the Proposed Plan.
B-3
-------
Tables
I:
-------
Table 2-1: Chemicals of Potential Concern (COPC) for OU2
Petroleum Products
TPH-Diesel
TPH-Gasoline
Volatile Organics
Benzene
Toluene
Ethyl benzene
Xylene (Total)
2-Butanone
4-Methyl-2-pentanone
Carbon tetrachloride
Methylene chloride
Trichloroethene (TCE)
1,1,2,2-Tetrachloroethane
1,1,1 -Trichloroethane
Tetrachloroethene (PCE)
Chlororrifluoromethane**
trifluoroethane
Methyl tert-butyl ether
Semivolatile Organics
Naphthalene
2-MethylnaphthaIene
Acenapthene
Acenaphthylene
Fluorene
Phenanthrene
Anthracene
Fluoranthene
Pyrene
Benzo(a)anthracene
Chrysene
Semivolatile Organics
(Cont'd.)
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
Indeno( l,2,3
-------
Table 2-2: Maximum Concentrations of Volatile Organic Compounds
Detected by Off-Site Laboratory at 0 to 10 Feet, MCAS YUMA, Operable Unit 2
Concentrations in milligrams per kilogram
Analyte
1,1-Dichloroethene
2-Butanone
Carbon Disulfide
Chloromethane
Freon 113
VIethylene Chloride
Tetrachloroethene
Toluene
Trichlorofluoromethane
Xylene
Residential Ris
Cancer
-
3.17
6.44
3.51
c-Based Criteria
Noncancer
2.22
2,770
3.89
1,130
1,930
338
484
142
1,930
Industrial Risk-Based Criteria
. Cancer
-
5.82
12
8.84
Noncancer
14.5
3,070
25.4
1,130
1,930
338
48.4
933
1,930
i
*
2.31
0.11
0.16
0.09
CA
2
*
*
0.077
*
#
*
oc
3
*
*
0.3
4
*
*
*
*
*
Notes:
-- indicates that this constituent does not have cancer and/or noncancer toxicity.
* indicates that this constituent was not a constituent of potential concern (COPC) for this CAOC.
ROD-VtlCl
Pa
-------
Table 2-2: Maximum Concentrations of Volatile Organic Compounds
Detected by Off-Site Laboratory at 0 to 10 Feet, MCAS YUMA, Operable Unit 2
Concentrations in milligrams per kilogram
Analyte
1 , 1 -Dichloroethene
2-Butanone
Carbon Disulfide
Chloromethane
Freon 113
Methylene Chloride
Tetrachloroethene
Toluene
Trichlorofluoromethane
Xylene
CAOC , , i
5
4
*
4
*
4
4
4
4
0.38
»
6 | 7
*
*
*
*
*
0.092
0.11
4
4
*
*
4-
0.089
4
4
0.23
*
*
*
4
8A J 8B
4
4
»
*
4
4
if
*
*
»
»
*
4
»
4
*
4
»
4
4
-9
0.075
4
4
0.22
*
*
*
*
4
*
10
#
4-
+
*
*
4
4
4
4
4
12
4>
4
*
4
4
4
4
0.053
*
4
13 | 14
4
»
t
4
»
6.44
4
»
4
4
4
4
4
4
4
4
4
4
4
4
15 | 16
»
4-
4
4
*
»
4
4
4
»
*
*
»
«
*
4
4
*
4
*
17
*
4
4-
*
4
*
»
4
»
4
18
»
*
4
4
0.05
0.106
4
4
4
4
ROD-V(XI.XLS
8/28/97 M2PM
Page 2 of 2
-------
Table 2-3: Maximum Concentrations of Semi-Volatile Organic Compounds and Total
Petroleum Hydrocarbons Detected by Off-Site Laboratory, Operable Unit 2,
Concentrations in milligrams per kilogram
, ..-'';'. Analyte. :f ' ' :/$
Semi-volatile organic compounds
1,2,3,5-Tetrachlorobenzene
l-Methyl-2-Pyrrolidinone
2-Cyclohexen-l-OI
2-Cyclohexen-l-One
2-Methylnaphtha lene
2-Pentene, 2-Methoxy
2-Pyrrolidinone, 1-Methyl
2,4-Dinitrotoluene
2-Pentanone, 4-Hydroxy-4-Methyl
4-Methylphenol
7H-Benz(DE)Anthracen-7-One
9,10-Anlhracenedione
Acenaphthene
Acenaphthylene
Anthracene
>enzene, l,4-Dimethoxy-2,3
Benzo(e) Pyrene
Benzo(a) Anthracene
)enzo(a) Pyrene
Jenzo(b) Fluoranthene
Jenzo (g,h,i) Perylene
)enzo(k) Fluoranthene
Benzo(b) Naphtho(23-D)Furan
Bis(2-Ethylhexyl) Phthalate
Butyl Benzyl Phthalate
Carbazole
Chrysene
Cyclopenta(deO Phenanthrenon
Di-n-Octylphthalate
Di-n-Butylphthalate
Dibenzo(a,h) Anthracene
3ibenzo(uran
Diethyl Phthalate
Ethanol. 2-[2-|4-(l,l,3.3-T
ithanone, 1-Oxiranyl
Sthylene Glycol
:luoranthene
Fluorene
Hexanedioic Acid. Bis(2-Ethyl)
ndeno (l,2,3
-------
Table 2-3: Maximum Concentrations of Semi-Volatile Organic Compounds and Total
Petroleum Hydrocarbons Detected by Off-Site Laboratory, Operable Unit 2,
Concentrations in milligrams per kilogram
. '.'.:" viAhalyte..H:'--;:'--:;.- .->
Semi-volatile organic compounds
1 ,2,3,5-Tetrachlorobenzene
l-Methyl-2-Pyrrolidinone
2-Cyclohexen-l-OI
2-Cyclohexen-l-One
2-Methylnaphthalene
2-Pentene, 2-Methoxy
2-Pyrrolidinone, 1-Methyl
2,4-Dinitrotoluene
2-Penlanone, 4-Hydroxy-4-Methyl
4-Methylphenol
7H-Benz(DE)Anthracen-7-One
9,1 0-Anthracenedione
Acenaphlhene
Acenaphthylene
Anthracene
Benzene, l,4-Dimethoxy-2,3
3«nzo(e) Pyrene
Benzo(a) Anthracene
Benzo(a) Pyrene
3enzo(b) Fluoranlhene
Benzo (g,h,i) Perylene
Benzo(k) Fluoranlhene
Benzofb) Naphtho(2,3-D)Furan
Bis(2-Ethylhexyl) Phlhalate
Butyl Benzyl Phthalale
Carbazole
Chrysene '
Cyclopenta(deO Phenanthrenon
Di-n-Octylphthalate
Di-n-Butylphthalate
Dibenzo(a.h) Anthracene
Dibenzofuran
Diethyl Phthalate
Ethanol. 2-|2-|4-(l,U,3-T
Ethanone, 1-Oxiranyl
Elhylene Clycol
Fluoranthene
Fluorene
Hexanedioic Acid, Bis(2-Ethyl)
lndeno(l,2,3.; .
''*£.:'
0.43
»
*
0.033
*
*
0.17
*
»
*
»
*
*
*
0.12
»
0.17
*
*
0.12
0.043
»
0.035
*
»
0.054
*
0.073
»
0.065
«
0.45
0.057
0.044
2.7
0.061
*
1,000
52
*
CA
»A:\
0.13
*
*
*
*
*
*
*
*
0.2
0.24
0.42
0.035
0.2
»
0.387
*
»
0.27
»
4.038
*
»
*
»
0.344
*
*
0.074
0.049
*
*
*
0.14
*
*
0.344
860
*
*
oc
s8B;|
-" ,*--. -
.;-:v""- .
*
»
*
*
*
*
*
*
*
»
*
*
*
*
*
*
*
1.738
*
*
*
*
»
*
*
*
*
*
*
*
*
»
22
»
»
: 9-;:
»
0.1
*
11
*
»
»
»
»
0.081
0.075
0.11
0.04
0.064
*
0.054
*
*
0.11
»
*
*
*
*
»
»
0.11
*
0.044
*
»
0.05
»
0.14
*
21
*
*
't*o!
- .,-'/;"
*
*
*
»
*
0.166
0.388
*
*
2.718
2.197
3.482
0.322
»
*
*
»
0.19
2.873
*
*
3.359
*
*
*
*
*
*
4.132
1.531
*
0.112
»
1.746
»
4.057
*
25
'.:- '.: ,
12 .
: V- ' '
*
*
*
*
*
*
*
»
*
*
»
»
»
*
*
0.844
0.614
*
»
2.426
*
»
»
»
*
*
»
*
*
»
*
*
»
*
»
'''IS-''.
*
*
*
*
*
*
»
*
*
*
*
m
*
0.0391
+
*
*
*
20.4
*
*
*
*
»
*
*
*
»
*
*
*
*
*
*
*
»
*
*
*
»
*
»
14
*
*
*
»
*
*
*
*
*
*
0.13
0.15
0.24
«
0.2
*
18
0.86
0.27
*
»
*
*
11
*
0.35
»
*
6.1
*
0.095
*
0.37
*
900
Page 2 of 3
-------
Table 2-3: Maximum Concentrations of Semi-Volatile Organic Compounds and Total
Petroleum Hydrocarbons Detected by Off-Site Laboratory, Operable Unit 2,
Concentrations in milligrams per kilogram
, :.'t -;.-.?;> ./,; v ; : .' ' .; _.;;?
/ :- .:>-:;^'&^Aniiyte:; -.--I- ".; O-;-.^
Semi-volatile organic compounds'
1 ,2,3,5-Tetrachlorobenzene
1 -Methy 1-2-Pyrrolidinone
2-Cyciohexen-l-OI
2-Cy clohexen- 1 -One
2-Methylnaphthalene
2-Pentene, 2-Methoxy
2-Pyrrolidinone, 1-Methyl
2,4-DinitrotoIuene
2-Pentanone, 4-Hydroxy-4-Methyl
4-Methylphenol
7H-Benz(DE)Anthracen-7-One
3,10-Anthracenedione
Acenaphthene
Acenaphthylene
Anthracene
Jenzene, l,4-Dimethoxy-2,3
Benzo(e) Pyrene
Benzo(a) Anthracene
Benzo(a) Pyrene
)enzo(b) Fluoranthene
Jenzo (g,h,i) Perylene
Benzo(fc) Fluoranthene
Benzo(b) Naphtho(23-D)Furan
Bis(2-Ethylhexyl) Phthalate
Butyl Benzyl Phthalate
Carbazole
Chrysene
Cyclopenta(deO Phenanthrenon
Di-n-Octylphthalate
Di-n-Butylphthalate
3ibenzo(a,h) Anthracene
Dibenzofuran
Diethyl Phthalate
Ethanol, 2-[2-|4-(l,U3-T
Ethanone, 1-Oxiranyl
Ethylene Glycol
Fluoranthene
Fluorene
Hexanedioic Acid, Bis(2-Ethyl)
Indeno (1,2,3-cd) Pyrene
N-Nitrosodiphenylamine
Naphthalene
Nonylphenol
Pentachlorobenzene
Phenanthrene
Phenol
Phenol, 2,2' - Methylenebis (6
Pyrene
Trans-Chlordane
Total Petroleum Hydrocarbons '
Diesel
Gasoline
Total Petroleum Hydrocarbons
iis;
»
*
*
*
*
»
*
*
*
*
*
»
»
»
»
*
»
*
*
*
*
»
*
*
»
*
»
*
*
*
»
*
CA
16
*
*
*
»
*
»
*
*
»
*
*
*
*
»
*
*
*
*
0.055
0.565
»
*
*
1.052
*
*
*
*
*
*
*
*
*
»
*
»
*
*
»
»
»
*
*
it
OC .;
17
»
*
*
*
»
*
*
*
*
*
»
»
»
»
»
»
*
*
*
»
*
*
*
»
*
*
*
*
*
29
*
*
18
*
*
*
*
*
*
»
*
*
*
*
»
*
*
*
»
*
*
*
*
2.45
*
»
*
»
*
*
0.056
*
*
*
»
0.037
*
0.047
»
*
*
»
Page 3 of 3
-------
Table 2-4: Maximum Concentrations of Pesticides and PCBs
Detected by Off-Site Laboratory at 0 to 10 Feet,
MCAS YUMA, Operable Unit 2
Concentrations in milligrams per kilogram
. " < Analyte . '.. ;:.:\;;:v'"
4,4-DDD
4,4-DDE
4,4-DDT
aldrin
aroclor 1242
aroclor 1254
aroclor 1260
dieldrin
endosulfan I
endosulfan II
endosulfan sulfate
endrin
endrin aldehyde
endrin ketone
heptachlor
heptachlor epoxide
alpha-benzene hexachloride
alpha-chlordane
beta-benzene hexachloride
delta-benzene hexachloride
gamma-chlordane
gamma-benzene hexachloride (lindane)
methoxychlor
prometon
Residential Ris
^^G^cer^^.
0.935
0.66
0.66
0.0132
0.0473
0.0473
0.0473
0.014
-
0.0499
0.0247
0.0453
0.173
0.158
0.158
0.173
0.173
c-Based Criteria
;;'^§Ji^ieam^!f
15.6
0.973
1.56
1.56
1.56
1.56
9.37
9.37
9.37
15.6
0.406
1.87
1.87
9.37
156
468
Industrial Risk
..X;B.V«^ .'.;' *i«OVyvi'j»v>; v
\?$&is$^
2.63
1.86
1.86
0.0371
0.176
0.176
0.176
0.0395
--
0.14
0.0694
0.143
0.486
0.499
0.499
0.486
0.486
-Based Criteria
">-J^b'iriiM$&-:';
113
6.76
11.3
11.3
11.3
11.3
67.6
67.6
67.6
113
2.93
13.5
13.5
67.6
1,130
3,380
CA
-:i>'
0.021
0.14
0.026
0.000088
t
0.02
0.39
0.014
»
0.015
0.013
0.0067
0.0097
0.018
#
0.0065
0.00027
0.17
*
0.0063
0.14
»
0.063
*
oc
'./.2'v
0.0076
0.092
0.044
0.00071
*
*
*
0.00457
»
»
0.00287
0.00414
0.00598
0.0018
»
4
*
0.0067
*
0.00122
0.009
*
0.00918
0.056
Notes:
- indicates that this
* indicates that this
for this CAOC.
constituent does not have cancer and/or noncancer toxicity.
constituent was not a constituent of potential concern (COPC)
ROrj-PSTl XI.S
»/:H/17(> 1.1PM
Page 1 of 3
-------
Table 2-4: Maximum Concentrations of Pesticides and PCBs
Detected by Off-Site Laboratory at 0 to 10 Feet,
MCAS YUMA, Operable Unit 2
Concentrations in milligrams per kilogram
Analyte
4,4-DDD
4,4-DDE
4,4-DDT
aldrin
aroclor 1242
aroclor 1254
aroclor 1260
dieldrin
endosulfan I
endosulfan II
endosulfan sulfate
endrin
endrin aldehyde
endrin ketone
heptachlor
heptachlor epoxide
alpha-benzene hexachloride
alpha-chlordane
beta-benzene hexachloride
delta-benzene hexachloride
gamma-chlordane
gamma-benzene hexachloride (lindane)
methoxychlor
prometon
,'v3
0.00123
0.003
0.0034
4
*
4
0.00164
4
4
0.0053
0.0016
0.00061
4
4
4
0.00094
0.0002
0.0014
*
4
4
4 | 5,.
0.125
0.07
0.026
0.0006
*
4
0.00098
4
4
0.0013
0.0037
0.00036
0.0016
4
0.00094
4
0.0052
0.0005
4
0.0057
*
4
4
0.014
0.013
0.011
0.00074
4
4
4
0.035
*
0.0042
0.00462
0.00793
0.0025
0.0045
4
0.19
0.00019
0.0021
0.16
0.00403
*
6 , -
0.00088
0.0065
0.0037
4
*
4
0.0034
0.001
0.00086
0.0012
4
4
4
.0.00093
0.00057
0.0083
4
0.00075
0.0082
4
0.0041
CAOC,
^ )! «* 4* v^ » i
% i^*7 IV«fc"*vH j»j|* > i
0.002
0.016
.0.0051
0.00027
0.016
4
0.55
0.00043
0.021
0.0047
0.0028
0.013
0.00066
0.00069
4
4
0.00054
0.00036
0.00046
0.00032
0.0025
*
0.00805
0.0079
0.0023
0.00248
4
4.045
0.0695
0.00136
0.0027
0.00098
0.04176
0.0174
0.01142
4
0.05873
0.00041
0.00756
0.00072
A8B; !'* \9 »'
0.00087
0.00207
0.00792
4
4
*
4
0.00506
*
*
*
0.01161
0.0869
0.00145
0.10152
4
4
4
0.0088
0.084
0.0077
4
0.048
0.0045
0.00094
0.00084
0.0013
0.0011
0.00044
0.012
*
0.0006
0.011
id
4
0.002
4
4
4
0.00079
4
0.00137
4
4
4
4
4
4
0.00067
4
4
4
12
*
4
4
*
4
4
4
4
4
4
4
*
4
4
4
4
4
4
4
4
ROD-rsn xi.
K/2R/97AI3
I
-------
Table 2-4: Maximum Concentrations of Pesticides and PCBs
Detected by Off-Site Laboratory at 0 to 10 Feet,
MCAS YUMA, Operable Unit 2
Concentrations in milligrams per kilogram
Analyte
4,4-DDD
4,4-DDE
4,4-DDT
aldrin
aroclor 1242
aroclor 1254
aroclor 1260
dieldrin
endosulfan I
endosulfan II
endosulfan sulfate
endrin
endrin aldehyde
endrin ketone
heptachlor
heptachlor epoxide
alpha-benzene hexachloride
alpha-chlordane
beta-benzene hexachloride
delta-benzene hexachloride
gamma-chlordane
gamma-benzene hexachloride (lindane)
methoxychlor
prometon
:-3S
4
0.0004
4
4
4
4
*
4
4
4
4
4
*
4
0.00108
4
*
4
0.00065
4
4
4
*
4
!§rf
0.0012
0.008
0.0047
*
*
*
»
0.0012
*
*
0.00052
4
4
4
»
0.0003
0.00072
0.0014
»
0.0039
0.0012
*
0.01
4
lilt
»
*
»
t
»
*
»
»
»
»
*
*
*
*
*
*
*
*
*
*
4
*
*
*
WiS
»
»
*
*
»
»
»
»
*
*
»
*
»
*
4
»
»
*
»
*
*
*
4
4
4
*
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
|1«
4
0.002
0.00191
*
*
*
*
*
*
0.00061
»
»
»
*
»
*
*
0.00206
0.00056
4
0.00144
4
4
4
ROP-PST! XIS
Page 3 of 3
-------
Table 2-5: Maximum Values Detected by Off-Site Laboratory and
Background Threshold Limit Values (TLV)
for Metals Detected at 0 to 10 Feet
Concentrations in milligrams per kilogram
Analyte
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium
Chromium VI
Cobalt
Copper
Lead '
Manganese
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Cyanide
Residential Ris
Cancer
0.302
0.129
26.5
4.07
--
--
--
--
c-Based Criteria
Noncancer ;'
71,100
28.4
21.3
1,520
356
35.6
71,100
356
4,540
2,630
136
21
1,420
356
356
4.98
498
21,300
1,420
Industrial Risk-1
1.9
0.859
45.4
6.97
~
-
-
--
Jased Criteria -.;,,.
100,000
532
399
12,400
6,650
665
100,000
6,650
29,600
49,200
1,180
382
26,600
6,650
6,650
93.1
9,310
100,000
26,600
iSlfcw
20,800
6.98
8.59
187
1.97
1.04
49.2
nd
12.2
15.4
15.8
319
nd
19.5
2.26
1.15
4.21
37.7
37.9
nd
$W4&£;-
26,200
16
437
0.43
6.2
32.2
*
16.6
47.1
102
727
1.3
39.3
0.59
42.1
0.5
56.7
101
*
Notes:
~ indicates that this constituent does not have cancer and/or noncancer toxicity.
* indicates that this constituent was not a constituent of potential concern (COPC) for this CAOC
nd indicates that no data were obtained for TLV calculations.
1 EPA Region IX residential and industrial soil screening levels for lead are 400 mg/kg and 1,200 mg/kg,
respectively. Concentrations below these values are not considered to have a negative health effect.
ROD-MET I.X(J
Pagl
-------
Table 2-5: Maximum Values Detected by Off-Site Laboratory and
Background Threshold Limit Values (TLV)
for Metals Detected at 0 to 10 Feet
Concentrations in milligrams per kilogram
Analyte
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium
Chromium VI
Cobalt
Copper
Lend '
Manganese
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Cyanide
CA(
TLV
12,000
6.72
8.5
143
0.39
0.59
38-2
nd
8.13
10.5
9.6
193
nd
17.9
3.07
1.2
6.1
23.4
23.3
nd
>C2
Maximum
5,450
10.2
3.5
124
*
3.4
24.6
»
3.5
22.8
232
145
0.12
9.5
+
*
1.2
22.9
135
*
CA(
TLV
9,980
6
4.24
223
0.33
0.48
45.4
nd
6.41
4.8
7.91
193
if
6.65
2.27
1.15
2.75
20.2
14.3
nd
)C3
Maximum,
5,160
4
5.1
129
»
2.4
21.4
0.36
3.9
42.6
103
201
*
24.9
0.65
»
*
19.1
112
4
CA(
*v \ ,
18,600
6
16.8
226
0.89
0.89
61.2
nd
6.94
8.25
11.5
521
4
9.25
5.94
1
16.8
43.1
35.4
nd
>C4, f ,
Maximum
12,800
»
6.3
171
»
3
24.4
»
6.5
33.8
88.5
574
0.35
15.9
0.69
4.4
*
40.3
220
4
CA(
t Ttv
26,400
7.78
21.3
675
0.85
6.38
30.0
nd
9.02
21.4
19.8
1,050
nd
20.1
4.87
1.34
11.5
43.1
49.2
nd
3C5
Maximum
6,120
*
3
92
*
4
17.2
»
3.3
15.5
43.5
170
*
7.6
0.61
4
4
33.8
79.2
*
RCID-METl.XLS
Page 2 of 6
-------
Table 2-5: Maximum Values Detected by Off-Site Laboratory and
Background Threshold Limit Values (TLV)
for Metals Detected at 0 to 10 Feet
Concentrations in milligrams per kilogram
Analyte
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium
Chromium VI
Cobalt
Copper
Lead '
Manganese
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Cyanide
CAC
TLV
20,500
6.52
6.06
270
0.7
1.03
30.1
nd
11.2
22.5
14.3
397
nd
15.4
3.76
1.19
3.54
27.5
37.5
nd
DC 6
Maximum
4,690
6.5
6.3
156
0.25
1
12.1
*
3.4
112
25.2
159
0.06
9.7
0.61
*
*
21
113
0.31
CAC
TLV -
31,400
7.44
15.6
334
4.02
1.09
38.8
nd
19.7
24.8
21.6
460
nd
27.4
2.93
1.01
3.9
61.6
60.8
nd
DC 7
Maximum
18,300
7.4
10.5
247
0.54
7.1
56.3
*
14.2
84.6
195
678
0.06
33.1
1.4
*
*
107
199
*
CAQG.8
' ''TLV; :.::.'
7,770
6
9.68
133
0.28
0.8
10.6
nd
6.12
21.7 '
8.79
137
nd
6.7
1.89
1.47
6.76
22.6
28.0
nd
8Ar Landfill
;Maxiirium
11,700
8.5
4.7
160
0.14
1.2
15.7
0.22
6.5
582
659
278
0.17
14.9
0.98
10.2
0.5
28
58.9
SB-Housing
Maximum
5,900
*
3.7
137
*
*
12.5
*
3.2
50.8
22.2
150
*
8
»
0
»
22.1
52.5
*
ROD-METl
K/2S/176-1B
.1
Pa
-------
Table 2-5: Maximum Values Detected by Off-Site Laboratory and
Background Threshold Limit Values (TLV)
for Metals Detected at 0 to 10 Feet
Concentrations in milligrams per kilogram
Analyte
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium
Chromium VI
Cobalt
Copper
Lead '
Manganese
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Cyanide
CAOC9
TLV
10,200
7.91
9.06
277
0.46
0.63
29.9
nd
9.47
8.37
9.88
183
*
1.88
nd
1
4.65
26.8
27.7
nd
Maximum
5,150
13.4
5
103
0.08
6.7
12.5
1.2
3.9
36.7
19.5
136
0.12
6.3
0.61
3.2
1.3
24.8
39.6
0.41
CAOC 10
TLV
6,310
7.11
8.99
184
0.28
1.64
25.1
nd
7.31
5.83
6.79
157
nd
9.83
1.9
1.14
7.88
26.9
30.2
nd
Maximum
5,290
*
3.9
85.3
0.67
1.7
11.2
»
3.7
5.5
31
176
*
6.8
0.63
0.78
*
22.3
157
»
CAOC 12
TLV
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
Maximum
*
»
«
»
4
*
*
*
*
*
»
*
#
*
+
»
*
*
#
*
CAOC 13
TLV
239,000
56.5
139
259
8.38
4.39
56.9
nd
48.9
45.9
103
2,280
nd
75
48.8
1
1
126
228
nd
Maximum
*
*
+
*
*
+
if
*
*
*
*
*
*
*
*
*
+
*
*
+
HOD-METl XLS
Page 4 of 6
-------
Table 2-5: Maximum Values Detected by Off-Site Laboratory and
Background Threshold Limit Values (TLV)
for Metals Detected at 0 to 10 Feet
Concentrations in milligrams per kilogram
Analyte
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium
Chromium VI
Cobalt
Copper
Lead '
Manganese
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Cyanide
CAOC 14
TLV | Maximum
59,000
6
13.1
408
2.68
1.97
40.2
nd
44.0
45.1
29.2
511
nd
46.5
13.1
1
3.66
79.6
78.2
nd
16,900
*
9.7
245
0.86
3.8
18.9
0.15
12.5
28.5
25.8
718
0.06
29.2
0.82
»
»
34
54.8
»
CAC
TLV
7,410
6
7.53
148
0.26
0.72
27.4
nd
5.81
4.14
9.71
166
nd
7.24
6.04
1
6.95
20.3
17.6
nd
>C15
Maximum
»
»
»
*
»
*
*
*
»
*
*
»
»
*
*
»
*
*
#
4
CAC
TLV L
19,100
8.26
10.6
135
0.55
1.72
17.8
nd
12.1
13.9
14.1
245
nd
16.0
3.43
1.18
7.98
30.7
40.1
nd
)C16
Maximum
4,460
*
4.2
170
*
»
6.6
*
2.5
90.4
4.6
138
»
5.3
*
*
*
21.9
148
»
CAC
TLV
10,800
8.36
11.9
120
0.38
0.68
43.4
nd
11.7
8.55
9
286
nd
18.7
3.34
1
7.35
41.6
29.5
nd
)C17
Maximum
3,800
*
4.3
105
»
*
7
»
3.3
26
4.5
130
*
7.2
*
*
*
20.2
57.6
»
ROD-METl.X
Pa
-------
Table 2-5: Maximum Values Detected by Off-Site Laboratory and
Background Threshold Limit Values (TLV)
for Metals Detected at 0 to 10 Feet
Concentrations in milligrams per kilogram
Analyte '
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium
Chromium VI
Cobalt
Copper
Lead '
Manganese
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Cyanide
::.- :;-.:',CAG
\M$:fi-;
10,900
8.27
11.1
127
0.42
0.73
19.3
nd
9.89
10.1
9.06
205
nd
11.7
3.07
1.48
7.16
35.6
39.9
nd
|q,18.;&.;:;-:,^
Maximum^
6,240
»
3.1
126
*
4-
13
*
*
10.4
13.5
148
»
6.7
»
»
*
28.8
31.2
*
ROD-MET).XLS
S/ZS/^MIKPM
Page 6 of 6
-------
Table 2-6: ARARs for Remediation of Asbestos-Contaminated Soil
MCAS Yuma
ARAR
Comments
Action-Specific:
Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP)
Clean Air Act (42 USCA
Ch85)
40 CFR Subpart M,
Section 61.145, 61.150,
and 61.154
NESHAP applies to demolition or renovation of facilities with
ACM. Remediation of ACM at MCAS Yuma is neither a
renovation nor demolition operation. However, procedures for
asbestos emission control (Section 61.145(c)); procedures for
ACM waste handling, transportation, and disposal (61.150); and
compliance of disposal facilities accepting ACM waste (Section
61.154) are considered relevant and appropriate.
Table 2-7: ARARs for CAOCs 1 and 10
MCAS Yuma
ARAR
Comments
Chemical-Specific:
Arizona Revised Statutes (ARS), Title 49 The Environment; as implemented in Arizona
Administrative Code (AAC) Title 18, Chapter 7, Article 2, Interim Soil Remediation
Standards
Arizona Revised Statutes
(ARS)
Title 49-151 and 152
Title 18, R18-7-201
through R18-7-209
Requires that soils be remediated to either: 1) background levels;
2) Health Based Guidance Levels; or 3) remediation levels
derived from a site-specific risk assessment. This ARAR is
relevant and appropriate.
-------
Table 2-8: Human Health Based Guidance Levels (HBGLs)
for Ingestion of Contaminants in Soil for COPCs at CAOC 1,8A, and 10
Appendix A to Title 18, Chapter 7, Article 2
June 1995 Update
Chemical
Acenaphthene
Acenaphthylene (PAH)
Anthracene(PAH)
Benz[a]anthracene(PAH)
Benzo[a]pyrene(PAH) (BaP)
Benzo[b]fluoranthene(PAH)
Benzo[k]fluoranthene(PAH)
Chrysene(PAH)
Dibenz[a,h]anthracene(PAH)
Fluoranthene(PAH)
Fluorene(PAH)
Indenopyrene(PAH)
Naphthalene(PAH)
Polychlorinated biphenyls (PCBs)
Polychlorinated b'iphenyls
Pyrene(PAH)
Cancer
Group
ND
D
D
B2
B2
B2
B2
B2
B2
D
D
B2
D
B2
ND
D
Residential Oral
HBGL
(mg/kg)
7000.0
7000.0
35000.0
1.1
0.19
1.1
1.1
110.0
0.11
4700.0
4700.0
1.1
4700.00
0.18
8.2
3500.0
Non-Residential
Oral HBGL
(mg/kg)
24500.0
24500.0
122500.0
4.6
0.80
4.6
4.6
462.0
0.46
16450.0
16450.0
4.6
16450.0
0.76
28.7
12250.0
Cancer Groups:
B2 Probable human carcinogen
D Not classifiable as to human carcinogenicity
ND No data
-------
Table 2-9: Alternative 3, Soil Volume Estimates
*&»
Gene^pesjOTjjJtiktt^^r s
A 5 - r <^
Approximate Area (sf)
Depth (ft)
Volume in Place (cy)
Excavated Volume (cy)
Soil requiring Disposal (cy)
-Unit North of
- ^Building 38 ,..
(CAOC 4A)
12,744
7 (average)
3,300
4,000
4,000
<; SubunitNear
Active Burn Pit Area
(CAOG7A)
26,400
1 (maximum)
1,000
1,200
1,200
Excavated volumes include 20 percent bulking factor
Totals rounded to nearest 100 cubic yards (cy)
Areas and volumes estimated from data collected in a field survey conducted
by U&A in February, 1996 (U&A, 1996a).
-------
Table 2-10: Cost Estimate
Alternative 3: Cleanup of ACM on Soil Surface and
Excavation and Disposal of Soil Mixed with ACM
il«L ' -' -I *\
Capital Cost
Sefwp
Mobilization
Fence Removal
Cleanup of ACM on Soil Surface
(See Table 2-11)
Excavation of Soil
Surveying
Excavation
Dust Control
Off Site Disposal
Waste Characterization
Rollup Bin Rental
Waste Disposal1
Transportation ;
Site Restoration
Site Grading
Sampling
Air Monitoring
Compaction Testing
Construction Cost Subtotal
Construction Management
(15%, excluding disposal)
1
1
1
1
5,180
13
2
100
6,750
207
3
13
3
fjJnir.^ ;
allowance
allowance
allowance
allowance
cy
day
allowance
ea
tons
load
allowance
day
ea
iUnitCo,
$5,000
$3,500
$91,000
$7,000
$12.00
$500
$1,000
$550
$32.25
$200
$2,540
$250
$400
Capital Cost Subtotal
Contingency (30%)
Total Capital Cost
(rounded to the nearest
Operation and Maintenance Costs
None.
Total Capital and O&M Costs
$1,000)
$5,000
$3,500
$91,000
$7,000
$62,160
$6,500
$2,000
$55,000
$217,700
$41,400
$7,620
$3,250
$1,200
$503,300
$42,800
$546,100
$163,800
$710,000
$710,000
'Tons of waste based on 1.20 tons per cubic yard and a wetting factor of 8 percent.
-------
Table 2-11 Cost Estimate
Cleanup of ACM on Soil Surface
i?8K"":: "
Capital Cost
Setup
Mobilization
Removal of ACM
Removal Activities
Dust Control
Off Site Disposal
Waste Characterization
Rollup Bin Rental
Waste Disposal
Transportation
Sampling
Air Monitoring
Construction Cost Subtotal
;,;iVf; ^v$yf
i
12
12
2
2
2
2
12
Unit
allowance
day
day
allowance
ea
load
load
day
Construction Management
(15%, excluding disposal)
Operation and Maintenance
None.
Capital Cost Subtotal
Contingency (30%)
Total Capital Cost
(rounded to the nearest
Costs
$1,000)
Total Capital and O&M Costs
' .:*f*£j*i}i.VM''
Unit Cost .;.Tqtal|pU|^
$5,000 $5,000
$3,500 $42,000
$500 $6,000
$1,000 $2,000
$550 $1,100
$560 $1,120
$200 $400
$250- $3,000
$60,620
$9,100
$69,720
$20,900
$91,000
$91,000
-------
Table 2-12: Potential ARARs for Remedial Action for MCAS Yuma
Medium/
Location
Requirements
Prerequisite
Citation
ARAR
Determination ..
''' " ''.". Comments . .
CHEMICAL-SPECIFIC:
Arizona Revised Statutes (ARS), Title 49 The Environment; as implemented in Arizona Administrative Code (AAC) Title 18, Chapter 7, Article 2, Interim Soil Remediation Standards
Contam-
inated soil
Sites that are legally
required to conduct soil
remediation.
Soils contaminated with
constituents identified in
Appendix A to the
regulation.
ARS 49-151 and 152.
R18-7-201 through. .
R18-7-209
Relevant and
Appropriate at
CAOC 1, 8A,
and 10
Requires that soils be remediated to either: 1) background levels; 2)
Health Based Guidance Levels; or 3) remediation levels derived
from a site-specific risk assessment.
U.S. EPA Guidance on Remedial Actions for Superfund Sites with PCB Contamination USEPA/540/G-90/007
Soils with
PCB
Contamina-
tion
Approach for evaluating
and remediating sites
with PCB
contamination.
Soils contaminated with
PCBs.
USEPA/540/G-90/007
Potential TBC
for PCBs at
CAOC 8A
Describes recommended approach for evaluating and remediating
sites with PCB contamination. Since compliance with ARS 49-151
and 152 is sufficient to protect human health and the environment,
this guidance is not considered TBC.
LOCATION-SPECIFIC:
National Historic Preservation Act, 16 USC Section 470-470w-6 [36 CFR Part 800] and the Archeolo
Within area
where action
m.iy cause
irreparable
harm, loss or
distraction of
significant
artifacts
Action to recover and
preserve artifacts.
Alteration of terrain that
threatens significant
scientific, prehistoric,
historic, or archaeological
data.
36 CFR Part 65
rical Resource Protection Act, 16 USC Section 470ii [36 CFR Part 299]:
Not an ARAR
Scientific, prehistoric, historic, or archaeological artifacts may be
present at MCAS Yuma. However, response actions for ACM at
MCAS Yuma do not require alteration of terrain or excavation of
native soil.
Endangered Species Act, 16 USC 1531 et stq.; and Fish and Wildlife Coordination Act, 16 USC 661 et seq.
Critical
habitat upon
which
endangered
spc-cii'S (ir
threatened
species
depend
Action to conserve
endangered species
including consultation
with the Department of
Interior.
Determination of effect
upon endangered or
threatened species its
habitat.
50 CFR Part 200,
50 CFR Part 402 and
33 CFR Parts 320 - 330
Not an ARAR
Federal threatened and endangered species have been recorded as
being potentially present on MCAS Yuma. Sites with ACM are
located on populated and highly trafficked area and do not support
wildlife. Response actions at MCAS Yuma is not anticipated to
affect habitat.
Iof3
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Table 2-12: Potential ARARs for Remedial Action for MCAS Yuma
Medium/
Location
Requirements
Prerequisite
Citation
ARAR
Determination
'..,''. - ,-.!''.. : - Comments
LOCATION SPECIFIC - Continued:
Migratory Bird Treaty Act of 1972, 16 USC 703
Migratory
bird area
Protects almost all
species of native birds in
the U.S. from
unregulated "take,"
which can include
poisoning at hazardous
waste sites.
Presence of migratory
birds.
16 USC 703
* ,
Not an ARAR
Migratory birds have been observed on and in the immediate
vicinity of MCAS Yuma. Sites with ACM are located on populated
and highly trafficked area and do not support wildlife.
Arizona Revised Statutes, Title 41 - State Government; Chapter 4.1 - History, Archaeology, and State Emblems; Article 4 - Archaeological Discoveries
Within state-
owned or
controlled
Kind
containing
archaeologic
al at historic
features
Prohibits excavation in
or upon, defacing, or
altering archaeological
or historical site or
objects; and require
notification upon
discovery of any such
site or object.
Existence of
archaeological,
paleontological, or
historic site or object at
least 50 years old..
ARS41-844A
Not an ARAR
Archaeological or historical site may be present at MCAS Yuma.
Sites with ACM are not located on archaeological or historical sites
or objects. Response actions for MCAS Yuma do not anticipate
excavation of native soil.
ACTION-SPECIFIC:
Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP); USC 7401 to 7671(q)
Waste, Soil,
and Debris
Management of ACM
and notification
requirements
Demolition, renovation,
or removal of ACM
40 CFR Subpart M;
Section 61. 145, 61.150,
and 61. 154
Relevant and
Appropriate
NESHAP apply to demolition or renovation of facilities with ACM.
Remediation of ACM at MCAS Yuma is neither a renovation nor
demolition operation. However, procedures for asbestos emission
control (Section 61.145(c)); procedures for ACM waste handling,
transportation, and disposal (61.150); and compliance of disposal
facilities accepting ACM waste with Section 61.154 is considered
relevant and appropriate.
2of3
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Table 2-12: Potential ARARs for Remedial Action for MCAS Yuma
Medium/
Location
Requirements
Prerequisite
Citation
ARAR
Determination
Comments
To Be Considered (TBC):
Chief of Naval Operations Instruction (OPNAVINST), 5100.23D, Cha)
Waste, Soil,
and Debris
Exposure to asbestos
fibers
Use, removal, and
disposal of ACM
>ter 17
5100.23C, Chapter 17
* .
Potential TBC
for ACM at
CAOC 4, 7,
and 9
The Navy manual provides guidance for controlling or eliminating
the exposure of Navy personnel to asbestos during the use,
removal, and disposal of ACM. Since these provisions apply
primarily to building structures and facilities, it is not considered to
be relevant and appropriate. In addition, since compliance with
NESHAP and federal OSHA is sufficient to protect human health
and the environment, this manual is not considered TBC.
U.S. EPA Guidance on Remedial Actions for Superfund Sites with PCS Contamination USEPA/540/G-90/007
. Soils with
PCB
Contamina-
tion
Approach for evaluating
and remediating sites
with PCB
contamination.
Soils contaminated with
PCBs.
USEPA/540/G-90/007
Potential TBC
for PCBs at
CAOC8A
Describes recommended approach for evaluating and remediating
sites with PCB contamination. Since compliance with ARS 49-151
and 152 is sufficient to protect human health and the environment,
this guidance is not considered TBC.
3of3
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Figures
-------
" Uli^" ."- _~-A/( ^
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t SHOPS AREA
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t. GOimCAST SEWAM LAOOON
10. ORONANOE MUMT1ONS OOFOML AACA
11. MOM110N OBPOBAL M£
U. TEAR OAS 8URML MCA
ia DRAM FCLD AREA
14. LAOOON SOUTH OF WUmO 17
IS. HAZARDOUS WASTE U8TS 9B> AMD 3M
M. HAZARDOUS WASTE U6TS.BUUMOS B04 AW B(M
17. HAZARDOUS WASTE UST tTOM
U. OLD DRUM STDRAOC AREA
.._ .^ .^7^
/ v// *\:??-y.'S;^r'}T£
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LEGEND
CERCLA AREA OF CONCERM
(CAOCI NUMBER
1500 780 0
1500
SCALE N FEET
DHW.IIHNI 0" IHl H.V, N«W. lUlcltlCS {dCINllltlvC CM»>NO
SOUTHWEST DIVISION
nr CO»»S "> SUlnx
FK3URE1-2:
UXATX3NOFCAOCSIN
OPERABLE UNIT 2
AS NOTED
-------
L_ . J
i_ IJt j Futures V«wed in AtnilPMtograpts
I RCRMrpeFwtty Autumn*
Sw"? <°> Soi SaMftng SvnplM
Baring br Sal Scnming Snnplis
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AnDyiis ndSoiScm
Ending Uoritoring Wet
Entng Sol Bonng locdon
Ondon d Suite* Drainigc
Topognfinic Depnsiion
bmMtd Hot Spot
SOUTHWEST DIVISION
FIGURE 3-1:
CAOC 1: FEATURE AND BORING LOCATION MAP
-------
i
, i
LEGEND
ON SHE LAB DATA-
SOI BOamC LOCtliON
CONTOut WTfUvAL' >mg/hg
BO01NC5 WIHOUI l«6CLS
-OFF SITE LAB DATA-
BOUNDARY OF SOUTHERN
DETAIL
too 100 o
200
SCALE W FEET
SOUTHWEST OMSWN
FIGURE 2-2:
CAOC1: TOTAL PAH CONCENTRATION CONTOURS
FOR SURFACE SAMPLES. SOUTHERN DETAIL
.i AS NOTED
-------
rc^Fi" >n
\
~i
\»
LEGEND
-ON SITC LAB OATA-
SOL BOftlHC I.OCAIIOM
CCNIOca MIERVAi. !rt OAU
BOUNDARY OF
NCRTi-£RN OEi
no too
SCALE IN FEET
00}
I o^< - - , * I
I . ^ SOUTHWEST DIVISION
lUAMSt ^Jwt'^ ».H iUI JS
; FIGURE 2-3:
; CAOC I. TOTAL PAH CONCENTRATION CONTOURS
FOR SURFACE SAMPLES. NORTHERN DETAIL
B ;
-------
- 1 '-''.:"
rr~ -
.- .171 V^?-'"' ,'-. -" ' " . "-"^/T-' ' "N"
u ^.'^'-. -"-'...'.%'
ROUBE 9-4:
CAOC 4: LOCATION Of ACM AND
ACM-CONTAMINATEO SOIL
-------
LEGEND
Fm Pa (Aam 4 Abandoned)
FonnerFueiaiadOers
Surface Stxi
»CM«ACl*Conumiuled
Sg^
Fomier Tunny
600 900
Approximate Scale in ftet
Sowc* JKOtn enynttrmg OIQUP. r99£
SOUTHWEST DIVISION
FIGURE 2-S:
CAOC 7: LOCATION OF SUBUNIT 7A
-------
B-7 ,<---'- = ,
////////////yj
CADC 7B
SDUTH DF CALA
ORDNANCE STORAGE AREA
LEGEND
/\ ..- -.'. »>& c- «=:ro; -iv
a i»o B
300
SOinHWEST DIVISION
S < SUI.ON YU»A.
FIGURE 24:
CAOC 7: LOCATION OF SUBUNfT 7B
i" AS NOICO
| «»
-------
o« Suspeaed Wasw
--- OHWSJI Aitl (CAOC S|
\ "SM i. '\^' j f c-3 ******
I . I Outunna waor SKIM Dnpot
1 ' - D«6ni
V/'lfV fe3^^--^^^-]
_~"^gr,.o '-='-, LL
Note CAOC8A««5F>«WiMDMt01 I
oomm tou«i oi No* Ontunct Ro«d !
RGURE J-7:
CAOC 8: FEATURE AND BORING LOCATION MAP
-------
2120
2119
FORMER SEW
DRYING
IIM'HIIHIIWMHIIIHIIL
ti MIOI Mil II fill
mCAOCI
X
V
I
DHIIHUIMHIIMIMmi1MIHHHIHIIMHHMIIlillUmilllllHIMIIMHIHI*l|UIHIIMHIIIMIHHIIH£
£ «
\ I
\ I
n K
i APROXIMATE LOCATION I
I OF ACM DEBRIS \
^'riltllllMllllltllMIIIMIIIMIIIItMMIItlllNnllMlllllllllltlllllMMHIIIItUIMIIIHIIIMIIinO^
I § i. (
FORMER
lilHOFF
ANKS
FORMER
SEWAGE
ijAGOONS
i
1
vic-fiwn v
M Af
..7
MAF-APCA
L_l
LEGEND
LITJ r"
N
ISO
300
450
Scale in Feet
ITT]
t 'IMII^Nl 0* tH««»
SOUTHWEST DIVISION
FIGURE J-»:
CAOC 9: LOCATION Ol ACM DEBRIS
-------
COMBAT AIRCRAFT
LOADING APRON
2100
-Q »Q
u
i/1
i/i\
VICINIT*
MAP
? -ffl0
FMI
MAP AREA
//£/ :.r
r- 2111
-2113
_. ,| /._
L--J-i !i
2105 2106 2107
000
FT
ia spot 30
R
JJ
NOBTHORONANCE ROAD
SOUTH ORONANCe ROAD
2115 r
- Otoptiyf icil
' mspeisr
APPROXIMATE FFA BOUNDARY CAOC 10
N
LEGEND
r I FFA Boundary '
^___j AenjiPncaoFeilurtj
I I Eiisnng Stiucnns
- fencetne
300
600
Approiifnale Scale in Feel
Souitt JiCOL'S ng**tnrq Cnuc I99C
SOUTHWEST DIVISION
FIGURE 5-9:
CAOC 10: FEATURE MAP
-7=7^
-------
£
I10P-2-0 42.40
--.-.........-J««»»
I10P2-02-1
-------
Use This Space to Write Your Comments
Your input on the proposed remedies for Operable Unit 2 is important to MCAS Yuma.
Comments provided by the public are valuable in helping MCAS Yuma select a final remedy
for the various CAOCs. You may use the space below to write your comments, and then fold
and mail. Comments must be postmarked no later than April 21,1997.
^
Additional comments on a separate piece of paper may be included.
Nc-me /t^.
A(«d
Ci;y
Zip
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