U.S. DEPARTMENT OF THE INTERIOR
BUREAU OF LAND MANAGEMENT
PALM SPRINGS-SOUTH COAST FIELD OFFICE
ENVIRONMENTAL ASSESSMENT
EA Number CA-660-02-24
______________________________________________________________________________
DATE:
20 March 2002
TITLE / PROJECT TYPE:
DESERT SCIMITAR 02 EXERCISE
CASE FILE / PROJECT NO.:
CACA 44015
FUNDING CODE: 1920
PROGRAM ELEMENT: EQ
BLM OFFICE:
Palm Springs-South Coast Field Office
690 W. Garnet Avenue, P.O. Box 1260
North Palm Springs, CA 92258-1260
APPLICANT / PROPONENT:
US Marine Corps
1st Marine Division (REIN)
BOX 555380
CAMP PENDLETON, CA 92055-5380
LOCATION OF PROPOSED ACTION: Areas near Quartzsite and Ehrenberg, Arizona;
the Colorado River; Blythe, Midland, Cadiz
Valley, and Desert Center, California
ENVIRONMENTAL ASSESSMENT
DESERT SCIMITAR 02 EXERCISE
Twentynine Palms, California to Yuma, Arizona
ADMINISTRATIVE FINAL
March 2002
Prepared by:
Anteon Corporation
3430 Camino del Rio North
San Diego, CA 92108
Applicant:
United States Marine Corps
1st Marine Division (Rein)
Box 555380
Camp Pendleton
Ca 92055-5380
Lead Agency:
U.S. Bureau of Land Management
Palm Springs South Coast Field Office
690 W. Garnet Ave.
N. Palm Springs, CA 92258
TABLE OF CONTENTS
1.0
1.1
1.2
1.3
1.4
1.5
2.0
2.1
2.2
2.3
2.4
2.5
2.6
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
3.10
3.11
3.12
3.13
3.14
3.15
4.0
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
4.14
4.15
5.0
5.1
5.2
5.3
5.4
6.0
7.0
INTRODUCTION...........................................................................................................................................1
PROJECT BACKGROUND ......................................................................................................................1
PROJECT PURPOSE AND NEED............................................................................................................1
KEY POINTS.............................................................................................................................................2
PURPOSE AND SCOPE OF THIS ENVIRONMENTAL ASSESSMENT ..............................................2
CONFORMITY WITH LAND USE PLANS ............................................................................................4
PROPOSED ACTION AND ALTERNATIVES ............................................................................................7
PROPOSED ACTION................................................................................................................................7
REDUCED ROUTE ALTERNATIVE ....................................................................................................21
BOAT LAUNCH ALTERNATIVE .........................................................................................................21
NO ACTION ALTERNATIVE................................................................................................................21
ALTERNATIVES ELIMINATED FROM FURTHER CONSIDERATION ..........................................21
PERMITS AND APPROVALS ...............................................................................................................22
DESCRIPTION OF THE AFFECTED ENVIRONMENT ...........................................................................23
SPECIAL MANAGEMENT AREAS ......................................................................................................23
GEOLOGY AND SOILS .........................................................................................................................24
WATER QUALITY .................................................................................................................................24
TRANSPORTATION AND ACCESS.....................................................................................................25
AIR QUALITY ........................................................................................................................................25
NOISE ......................................................................................................................................................29
BIOLOGICAL RESOURCES..................................................................................................................29
CULTURAL RESOURCES.....................................................................................................................38
PALEONTOLOGICAL RESOURCES....................................................................................................38
VISUAL RESOURCES ...........................................................................................................................38
RECREATION / VISITOR SERVICES ..................................................................................................39
PUBLIC SERVICES AND UTILITIES...................................................................................................39
WASTES (HAZARDOUS/SOLID) .........................................................................................................39
SOCIOECONOMICS...............................................................................................................................39
ENVIRONMENTAL JUSTICE AND PROTECTION OF CHILDREN.................................................39
ENVIRONMENTAL CONSEQUENCES AND MITIGATION..................................................................41
CRITICAL ELEMENTS OF THE HUMAN ENVIRONMENT .............................................................41
GEOLOGY AND SOILS .........................................................................................................................41
WATER RESOURCES............................................................................................................................43
TRANSPORTATION AND ACCESS.....................................................................................................44
AIR QUALITY ........................................................................................................................................46
NOISE ......................................................................................................................................................47
BIOLOGICAL RESOURCES..................................................................................................................49
CULTURAL RESOURCES.....................................................................................................................56
PALEONTOLOGICAL RESOURCES....................................................................................................57
RECREATION/VISITOR SERVICES ....................................................................................................58
PUBLIC SERVICES AND UTILITIES...................................................................................................59
HAZARDOUS MATERIALS..................................................................................................................61
SOCIOECONOMICS...............................................................................................................................62
CUMULATIVE IMPACTS .....................................................................................................................63
US COAST GUARD BRIDGE PERMIT REQUIREMENTS.................................................................63
COORDINATION AND CONTACTS.........................................................................................................65
FEDERAL AGENCIES ...........................................................................................................................65
STATE AGENCIES .................................................................................................................................66
LOCAL AGENCIES ................................................................................................................................67
NATIVE AMERICAN TRIBES (through YPG) .....................................................................................68
LIST OF PREPARERS .................................................................................................................................69
REFERENCES..............................................................................................................................................70
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LIST OF TABLES
Table 1. Unit, Home Base, and Number of Personnel Participating in the Exercise. ....................................................8
Table 2. Vehicles, Watercraft, and Aircraft Used in Exercise. ......................................................................................9
Table 3. Sites Used in the Exercise..............................................................................................................................15
Table 4. Radio Retransmission Sites. ..........................................................................................................................17
Table 5. Vehicle Location at the End of Each Day of the Desert Scimitar 02 Exercise. .............................................19
Table 6. Desert Scimitar 02 Route Segments by Task Force.......................................................................................20
Table 7. Permits and approvals....................................................................................................................................22
Table 8. Federal and state ambient air quality standards. ............................................................................................26
Table 9. State ambient air quality standards with no Federal counterpart. ..................................................................27
Table 10. Significant Emissions Thresholds................................................................................................................28
Table 11. T&E and sensitive plant species that may occur within the project area.....................................................32
Table 12. Threatened and endangered wildlife potentially occurring in the project area. ...........................................32
Table 13. Summary of potential impacts on BLM critical elements. ..........................................................................41
Table 14. Air emissions predicted for Desert Scimitar 02...........................................................................................46
LIST OF FIGURES
Figure 1. Desert Scimitar 02 Routes, California and Arizona.
Figure 2. Desert Scimitar 02 Assembly Areas, California and Arizona.
Figure 3. Cadiz Road, California.
Figure 4. Granite Pass Assembly Area, California.
Figure 5. Assembly Area Iron Mountain, MWD California Aqueduct Pumping Station.
Figure 6. Borrow Pit, Colorado River Indian Tribes Reservation, California.
Figure 7. Postmile 10 (Cal Trans Storage Yard) Assembly Area, California.
Figure 8. Desert Center Airport Assembly Area, California.
Figure 9. Wiley Well Road/Milpitas Wash Road, California.
Figure 10. Palen Pass Road/Arlington Mine Road, California.
Figure 11. Assembly Area Blythe.
Figure 12. Assembly Area Midland.
Figure 13. Riverside County Landfill and Midland LTVA Assembly Areas, California.
Figure 14. Assembly Areas near Palo Verde, California.
Figure 15. Assembly Area and River Crossing Near Palo Verde, California and Arizona.
Figure 16. Assembly Area, Cibola BOR Stockpile Yard C-105.3, Arizona.
Figure 17. Ehrenberg Assembly Area, Arizona.
Figure 18. BLM “Road Runner” 14-day Visitor Area South of Quartzite, Arizona.
Figure 19. Tom Wells Road/Jeep Trail from Ehrenberg to Felipe Pass, Arizona.
Figure 20. Assembly Areas along Cibola Road, Yuma Proving Ground.
Figure 21. Assembly Areas along Cibola Lake Road, Yuma Proving Ground, Arizona.
Figure 22. Assembly Areas along Cibola Lake Road, Yuma Proving Ground, Arizona.
Figure 23. Assembly Areas along Cibola Lake Road, Yuma Proving Ground, Arizona.
Figure 24. Assembly Areas along Cibola Lake Road, Yuma Proving Ground, Arizona.
Figure 25. C-17 Airstrip Assembly Area, Yuma Proving Ground, Arizona.
Figure 26. Castle Dome Annex Assembly Area, Yuma Proving Grounds, Arizona.
Figure 27. RTX 1, California.
Figure 28. RTX 2, California.
Figure 29. Granite RTX, California.
Figure 30. Rice RTX , California.
Figure 31. Desert Center RTX , California.
Figure 32. Prison RT1, California.
Figure 33. RC RTX, California.
Figure 34. McCoy Mountain RTX, California.
Figure 35. Big Maria Mountain RTX, California.
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Figure 36. Chuckwalla Mountain RTX, California.
Figure 37. Iron Mountain RTX, California.
Figure 38. Stone Cabin RTX, Arizona.
Figure 39. Traffic Control Points Near River Crossing, California and Arizona.
APPENDIX
Desert Scimitar PowerPoint Presentation, 11 Jan 02.
Desert Scimitar 02 Exercise
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Introduction
1.0
INTRODUCTION
1.1
PROJECT BACKGROUND
Desert Scimitar is the name of an annual 1st Marine Division field exercise traditionally carried out at the
Marine Corps Air Ground Combat Center (MCAGCC) - Twentynine Palms, California. Although past
exercises provided an opportunity for Division units to practice live-fire and combat maneuvers, they
lacked the geographical scope needed to test the command and control, and logistical capabilities of the
Division. To correct this situation, planners of Desert Scimitar 01 (2001) sought ways to test and train the
Division’s command and control element under conditions more representative of the distances and terrain
they would encounter in battle.
Desert Scimitar 01, held 1-12 May 2001, was the 1st Marine Division’s inaugural attempt at conducting a
division-sized command and control exercise, almost exclusively on public and private lands. Due to the
advice, support and cooperation of numerous Federal, state and local agencies, as well as the hospitality of
private landowners, this pilot program was a tremendous success. The exercise was well received by the
local populace, and received favorable press. More importantly, the exercise objectives were met,
validating the importance of this type of training for the Division command element.
1.2
PROJECT PURPOSE AND NEED
The purpose of Desert Scimitar 02, and future Desert Scimitar exercises, would remain the same: to test
and train the Division’s command and control element under conditions more representative of the
distances and terrain the 1st Marine Division would encounter in battle. As this past year’s exercise
demonstrated, the desert region in southeastern California and southwestern Arizona remains an ideal
location to test the Division’s capabilities, because the climate, terrain, and hydrology are so similar to
Southwest Asia. Since existing military training installations in the region do not by themselves possess the
range of conditions needed to fully implement the exercise, the ability to extend the exercise area beyond
the boundaries of existing military installations and onto other public or private lands remains critical to
testing the Division’s physical, logistical, and communication capabilities. In addition, the ability to
overcome natural and man-made water obstacles such as rivers and flooded lands remains vital to
measuring the Division’s warfighting capability. Division planners remain committed to cooperating with
land management agencies in Arizona and California, and would continue to be guided by the principle of
avoiding environmentally sensitive areas and minimizing potential impacts whenever possible. See the
PowerPoint presentation slides in the Appendix for additional information.
In order to capitalize and expand upon the success of the pilot exercise, the 1st Marine Division seeks to
extend the exercise (or project) area to include routes and assembly areas that were initially considered in
the early planning phases of Desert Scimitar 01 but which had to be dropped from further consideration due
to time and financial constraints. For example, the Division proposes to use new routes along Cadiz Road,
Palen Pass Road, and Wiley Well/Milpitas Wash Road, among others. Last year’s exercise revealed several
additional areas that would greatly enhance future training. This would include private lands like the
Midland town site, utility property such as the Metropolitan Water District’s Iron Mountain pumping
station, and areas that could be used for retransmission sites on high ground. In addition, the Division plans
on exercising units down to the company level, thus slightly increasing the number of Marines and vehicles
involved in the exercise. Although the initial intent for Desert Scimitar 01 was to exercise down to the
company level, time constraints prohibited the Division from obtaining enough maneuver space to make
this scale of exercise possible. Finally, the Division desires a long-term cooperative agreement from the
cooperating agencies, which would ensure that Desert Scimitar would be an annual event; however,
analysis of a long-term agreement would not take place until after the completion of this Desert Scimitar
02.
Based on the success of Desert Scimitar 01, the 1st Marine Division proposes the establishment of an
exercise designed to test the Division’s ability to accomplish the missions assigned to it in a current
Operations Plan (OPLAN), which is designed to respond to aggression in the Middle East. The primary
focus of the exercise is to practice and test the abilities and procedures of the Marines and equipment that
Desert Scimitar 02 Exercise
Twentynine Palms, CA to Yuma, AZ
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Introduction
make up the respective Combat Operations Centers (COCs). This exercise is vital to ensuring the mission
readiness of the 1st Marine Division.
The specific objectives of Desert Scimitar 02 are to:
1.3
·
Test the Division’s and subordinate units’ abilities to rapidly embark and deploy their forces in response
to an execution order.
·
Exercise command, control, and communication over moving forces separated by large distances, across
terrain which closely simulates the terrain of the actual Area of Operations (AOR).
·
Test the ability of new communications systems and the Marines who use them.
·
Test the ability of the Division and subordinate and supporting units to conduct a river crossing, to
include all of the tactical control measures and coordination required to move a division’s worth of
equipment and personnel.
·
Test the ability of the Division and subordinate and supporting units to provide logistical support to a
division’s worth of equipment and personnel across extended distances.
·
Force Marines (planners and operators) to operate in unfamiliar terrain.
KEY POINTS
To ensure that reviewing agencies and the public understand the nature of military testing and training
proposed for this exercise, the following statement is made at the beginning of this document.
The Desert Scimitar 02 exercise involves:
a)
No “live-fire” or simulated fire.
b) No pyrotechnics, smoke, or obscurants.
c)
No “aggressor forces.”
d) No physical engagements.
e)
No “off-road” maneuvers or “free play.”
f)
No tracked combat vehicles.
g) No nighttime exercises.
These aspects of the exercise are explained in detail in the Proposed Action and Alternatives section below.
1.4
PURPOSE AND SCOPE OF THIS ENVIRONMENTAL ASSESSMENT
1.4.1
FEDERAL ACTION
The National Environmental Policy Act (NEPA) of 1969 (42 U.S.C. 4321 et seq.) requires Federal agency
decisionmakers to consider the impacts of major Federal actions with the potential to significantly affect
the quality of the human environment. As a Federal agency, the US Marine Corps (USMC) 1st Marine
Division has incorporated NEPA compliance into the planning and decisionmaking for the proposed Desert
Scimitar 02 exercise. This process has followed the procedures and requirements of the US Marine Corps
“Environmental Compliance and Protection Manual,” MCO P5090.2A, PCN 10207187100 (10 Jul 1998).
As the principal land management agency cooperating on this project, the US Department of the Interior,
Bureau of Land Management (BLM) has agreed to serve as lead agency for the purposes of this
environmental assessment. The BLM Palm Springs Field Office has been designated as the lead office.
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Introduction
Accordingly, NEPA compliance for this action follows the BLM policies and procedures. Other authorizing
or permitting agencies may use this Environmental Assessment (EA) in their own project evaluations.
1.4.2
GUIDING POLICIES
Instructional Manual (IM) No. 2001-030 “Military Activities On and Over Public Lands” (2000) provides
policy guidance to the BLM field offices regarding the use of public lands for Federal military purposes.
The primary statutory foundations for this IM are the Federal Land Policy and Management Act (FLPMA),
(90 Stat. 2743; 43 U.S.C. 1701, et seq.) and the Engle Act (72 Stat. 27; 43 U.S.C. 155-158). The primary
regulatory guidance is at 43 CFR Parts 2300, 2800, and 2900. This IM is a compilation and restatement in a
single document of statutory, regulatory and policy guidance that affects the authorization of military
activities which may impact public lands managed by the BLM.
The following are some key excerpts of this policy document that relate to the Proposed Action:
The laws of the nation and the administrative history clearly indicate that title to the public lands
rests with the U.S. Government, and that these lands are a national asset under the control of
Congress. Congress has indicated by statute that public lands are available for a variety of uses,
including use by other Federal agencies and departments. Through FLPMA, Congress has placed
the public lands under the jurisdiction of the Secretary of the Interior, to be administered by the
BLM consistent with all the public lands laws and regulations.
I. GENERAL POLICY
B. Requests for use of the public lands for military activity are not given any special status.
Proposals made to the BLM must be considered within the BLM’s existing processes, including land
use planning, compliance with the National Environmental Policy Act of 1969 (NEPA), other
natural resource and cultural resource laws and Executive Orders, and standard public
participation practices. The NEPA analysis must address why existing military lands cannot
accommodate the proposed use.
D. Factors that must be evaluated in decision making documents include Resource Management
Plan conformance, public safety, environmental affects, and effects on other public land users.
E. All authorizations for military activity, except transferring lands as real property to the military
and withdrawing land for uses involving hazardous materials, must provide the proponent agency
the minimum land area, uses, and rights necessary to accomplish the authorized activity in a safe
and generally unimpeded manner, subject to valid existing rights.
O. Unauthorized use of public lands by any military unit shall be terminated as soon as possible,
with appropriate restoration of resources. All incidents of unauthorized use shall be reported by
Field Offices to the military commander. If resolution cannot be achieved, report the incident to the
BLM State Director. The State Director should take appropriate action to work with the responsible
installation commander or State Adjutant General to resolve the unauthorized use and to ensure the
situation is not repeated. The State Director may forward incident reports, along with any
recommendations for action, to the Director (WO-350).
III. AUTHORIZATIONS AVAILABLE FOR MILITARY USE OF PUBLIC LANDS
The type of authorization which may be permitted/granted or, in the case of withdrawal, recommend
by a BLM authorized officer (AO) for the military’s use of the public lands is governed by the
following considerations: (1) whether the authorization is to be issued to a Federal agency or to a
State agency; and (2) the extent and degree/intensity of the effects of the proposed activity.
Desert Scimitar 02 Exercise
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Introduction
B. Determining the appropriate authorization to use:
1. The BLM AO first determines whether the proponent agency and forces proposing to use the
public lands are Federal or SNG.
2. Then the AO analyzes the proposed use to determine the type of authorization which would
provide the military agency with the authority and control necessary to carry out its activities in a
reasonably safe and generally unimpeded manner, while maintaining as much use by other public
land users as is feasible. Considerations should include:
a.
b.
c.
d.
e.
f.
Safety considerations for the public and BLM employees.
Effects on the environment.
Effects on other public land users.
Feasibility of reclaiming the lands and the associated costs.
Duration of the authorization and whether the use is continuous or intermittent.
Such other factors as the AO may deem to be relevant.
C. Decision process: When the AO has determined which authorization is most appropriate, the standard
BLM processes and policies leading to a decision whether to authorize the proposed activity are to be
followed.
Using the guidelines provided in the IM, the BLM Palm Springs Field Office has determined that the
appropriate authorization for this action would be a cooperative agreement under Section 307 of the
FLPMA.
1.4.3
SCOPE OF THE ENVIRONMENTAL ASSESSMENT
This EA has been prepared to evaluate the potential environmental impacts of the proposed Desert Scimitar
02 exercise and to identify mitigation measures to avoid or decrease those impacts to levels that are less
than significant. Several cooperating agencies provided information and guidance used in planning the
exercise and in preparing this EA (see Chapter 5, Coordination and Contacts). Existing agency documents,
maps, and databases provided much of the baseline data used in the analysis. This was supplemented by
field surveys, inspections, and data analyses conducted specifically for this project.
Several key environmental concerns were raised during the agency and public scoping process, including
potential negative impacts the exercise might have on:
·
State and Federally listed species.
·
Archeological resources.
·
Recreation and access to public lands.
·
Introduction of non-native plant species to and from California and Arizona.
·
River navigation.
Potential impacts to these and to other resource elements are discussed in the EA. The scope of this EA is
limited to the potential impacts of the proposed 2002 exercise. Development of a repeatable, multi-year
Desert Scimitar exercise program would require additional analysis and amendment of this EA.
1.5
CONFORMITY WITH LAND USE PLANS
The proposed project area for the Desert Scimitar 02 exercise spans two states, an interstate waterway, five
BLM field offices (Palm Springs, El Centro, Barstow, Needles, and Yuma), and two military reservations
(Yuma Proving Ground and MCAGCC). BLM and other agencies manage these areas guided by their
respective land use plans. The key plans are described below.
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Introduction
The proposed Desert Scimitar 02 exercise would conform to all of these land use and resource management
plans.
California
California Desert Conservation Area Plan 1980 (CDCA Plan), as amended (BLM 1999). This plan
provides general, regional guidance for BLM management of the CDCA over a 20 year time period. The
general plan provides the framework for subsequent plans for specific resources and uses, and for
development of site-specific programs or project actions, and is responsive to specific land use requests. It
includes most all of the California portion of the proposed project area. According to the CDCA Plan, the
proposed project area is limited to moderate use where protection and conservation of desert resources is
ensured and impacts are mitigated. The proposed project conforms to this classification.
Draft Northern and Eastern Colorado Desert Coordinated Management Plan and Environmental
Impact Statement (NECO-EIS) (BLM 2001). This proposed plan would update the CDCA Plan for parts
of the Needles, Palm Springs, and El Centro BLM Districts comprising the northern and eastern Colorado
Desert region. The primary purpose of this document is to amend or create land use plans and specific
management prescriptions for species and habitats on Federal lands, proving in particular for the recovery
of the desert tortoise. It includes most all of the California portion of the proposed project area.
Midland Long-term Visitor Area Management Plan and Environmental Assessment (BLM 1996).
This plan describes environment and management goals of Midland LTVA.
Desert Tortoise (Mojave Population) Recovery Plan (DTRT 1994). This recovery plan describes the
recovery objective and delisting criteria, the recovery strategy and underlying principles, and actions
needed to achieve recovery in the California desert region. It includes all of the California portion of the
proposed project area.
Multiple Land Use Management Plan. Marine Corps Air Ground Combat Center (MCAGCC),
Twentynine Palms, California, 1996-2000 (USN 1996). This plan includes those portions of the proposed
project taking place at MCAGCC.
Arizona
Final Ehrenberg-Cibola Recreation Area Management Plan (BLM 1994). This document outlines
actions that would guide the recreation management on public lands within the Ehrenberg-Cibola Special
Recreation Management Area.
Draft Range Wide Environmental Impact Statement, US Army Yuma Proving Ground, Yuma and
La Paz Counties, Arizona (USAYPG 1998). The YPG Range Wide EIS discloses the direct, indirect, and
cumulative effects of a proposal to diversify YPG operations, including the use of YPG for military
training. Specific land use plans are incorporated by reference into this document. This EIS encompasses
the portion of the proposed project area within YPG.
La Posa Interdisciplinary Management Plan (BLM 1996b). This plan describes environment and
management goals of La Posa Long-Term Visitor Area (LTVA) and adjacent areas, including Roadrunner
assembly area.
California / Arizona
Final Yuma District Resource Management Plan and Environmental Impact Statement as amended
(BLM 1987). This plan includes all the Arizona portion of the proposed project area outside of YPG. It
also covers public lands along the Colorado River, under Departmental Manual (DM) 613.
Biological Opinion on the Description and Assessment of Operations, Maintenance, and Sensitive
Species of the Lower Colorado River, US Bureau of Reclamation, Lower Colorado Region (USFWS
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Environmental Assessment – March 2002
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Introduction
1997). This biological and conference opinion (BO) addresses the Bureau of Reclamation’s (BOR)
discretionary program of continuing operations of Lower Colorado River (LCR) dam facilities,
maintenance of river control features, and other activities such as endangered species conservation for the
next five years. It includes portions of the proposed project area occurring in and along the Lower Colorado
River.
Final Environmental Impact Statement, Yuma Training Range Complex, located in Southwestern
Arizona and Southeastern California (USMC 1997). This document describes the regional environment,
biological constraints, and military use of airspace and lands in the project area.
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Description of the Affected Environment
2.0
PROPOSED ACTION AND ALTERNATIVES
This section describes the Proposed Action, Reduced Routes Alternative, Boat Launch Alternative, No
Action Alternative, alternatives eliminated from further consideration, and the permits and authorizations
required to implement the actions.
2.1
PROPOSED ACTION
The 1st Marine Division (Reinforced) proposes to conduct a long-range tactical command, control and
communications (C3) exercise between the Marine Corps Air Ground Combat Center (MCAGCC),
California and the US Army Yuma Proving Ground (YPG), Arizona from 22 April to 3 May 2002. Figure 1
shows the proposed exercise routes. The PowerPoint slides in the Appendix include additional information
about the exercise. The exercise would involve 600 wheeled vehicles, and 2,200 Marines. No tanks or
amphibious tracked vehicles would be used. Tracked construction equipment used at the bridgeheads of the
river crossing would be trailered in and out, and used only at those sites. Bridgehead construction and
restoration would begin April 15 2002 and would end May 10 2002. The exercise would not involve any
sort of live fire activities and all enemy engagements would be scripted scenarios conducted over radios.
All training activity would occur during daylight hours. Upon completion of the day’s training activity,
units would retire to pre-designated and approved bivouac (camping) sites to rest, eat, and conduct debriefs
of the training to date. The following day, units would assume their previous positions and resume training.
All travel would occur on existing roads (paved and improved surface), with the exception of a portion of
Ehrenberg Wash Road, an established, graded road that travels along a wash in areas. All assembly areas
would be established on developed properties or pre-disturbed sites. Contracted sanitary and waste facilities
would be provided at each overnight assembly site. Each unit would bring in food, water, and other
supplies; there will be no shower facilities, but hand washing facilities will be available. Standard
hazardous material procedures would be implemented at all bivouac sites to ensure a maximum level of
protection and to prevent potential contamination of the soil from spills.
2.1.1
PERSONNEL, VEHICLES, AND EQUIPMENT
Personnel from several 1st Marine Division units, along with Marine and Navy units from other commands,
would participate in this exercise. Table 1 gives a breakdown of the number of personnel by unit. The
majority of the participants would travel to the exercise area from Marine Corps Base Camp Pendleton.
Other units would come from the Marine Corps Air Ground Combat Center; Port Hueneme Naval Base,
CA; and Marine Corps Air Station Yuma (MCASY), AZ. Most of the units would convoy to the exercise
area in military vehicles and buses; some would be airlifted.
Marines would employ several modes of transportation during the exercise for administrative, operational,
engineering, and logistical purposes. Table 2 provides a summary of the type and number of vehicles
involved in the exercise. The great majority of the miles traveled by these vehicles would be on paved
highways, with a considerably lesser amount on improved dirt roads (and most of that on YPG).
Highly Mobile Multi Wheeled Vehicles (HMMWVs, or “Humvees”) would be the principal vehicle used
during tactical maneuvers, along with a lesser number of 5-Ton Trucks and Light Armored Vehicles
(LAVs). Logistics Vehicle Systems (LVS) would be used to haul heavy equipment, bridge components,
fuel bladders, and supplies. These large tractor trailer-type trucks would move between assembly areas and
would stay on the primary route.
Heavy construction equipment would be brought in for bank preparation work and to assist in deployment
of the floating ribbon bridge. Once bridge components were in the water, several Bridge Erection Boats
(BEBs) would be used to ferry and assemble bridge bays, and to maintain the position of the ribbon bridge
against the current. Other boats would be positioned upstream and downstream of the bridge to ensure
recreational boaters do not approach the rafting and bridging operations.
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Description of the Affected Environment
At the end of the exercise, U.S. Air Force cargo planes would airlift equipment, supplies, and troops from
Laguna Army Airfield at Yuma Proving Ground, and Marine Corps Air Station Yuma, to March Air
Reserve Base in California. CH-46E and CH-53E helicopters would transport personnel and cargo between
the assembly areas. These aircraft would use approved flight corridors and follow established Federal
Aviation Administration regulations when moving between sites. Established helicopter landing sites
(airstrips or heliports) are located at Iron Mountain (Figure 5), Yuma Proving Ground (Figure 18), and the
Blythe Airport (Figure 11); additionally, BOR 105.3 (Figure 16), Felipe Pass, and the Midland area site
would be used for helicopter landings. Four helicopters in total would be used..
Table 1. Unit, Home Base, and Number of Personnel Participating in the Exercise.
Unit
Unit Abbrev.
Home Base
1st Marine Division Headquarters
1st Mar Div Hq
st
1 Marine Regiment
1st Battalion 5th Marine Regiment
2d Battalion 5th Marine Regiment
No. of
Personnel
Camp Pendleton
500
st
1 Mar Regt
Camp Pendleton
150
1/5
Camp Pendleton
60
2/5
Camp Pendleton
7th Mar Regt
MCAGCC-29 Palms
150
3d Battalion 7th Marine Regiment
3/7
MCAGCC-29 Palms
60
3d Battalion 4th Marine Regiment
3/4
MCAGCC-29 Palms
60
7th Marine Regiment
rd
rd
23 Marine Regiment
23 Mar Regt
Reserve Regiment
11th Marine Regiment
11th Mar Regt
Camp Pendleton
60
60
150
1st Battalion 11th Marine Regiment
1/11
Camp Pendleton
80
3rd Battalion 11th Marine Regiment
3/11
MCAGCC-29 Palms
80
5th Battalion 11th Marine Regiment
5/11
Camp Pendleton
80
1 Tank Battalion
1st Tk Bn
MCAGCC-29 Palms
70
1st Light Armored Reconnaissance Battalion
1st LAR
Camp Pendleton
70
3rd LAR
MCAGCC-29 Palms
70
st
rd
3 Light Armored Reconnaissance Battalion
Tactical Exercise Control Group
TECG
Camp Pendleton
140
1st Combat Engineer Battalion
1st CEB
Camp Pendleton
50
60
st
st
1 Reconnaissance Battalion
1 Recon Bn
Camp Pendleton
7th Engineer Support Battalion
7th ESB
Camp Pendleton
60
Naval Mobile Construction Brigade 4
NMCB 4
Port Hueneme
20
Combat Service Support Detachment 17
CSSD 17
Camp Pendleton
rd
rd
3 Low Altitude Air Defense
3 LAAD
Total Number of Personnel
Camp Pendleton
150
20
2,200
Because state seat-belt laws limit the number of occupants to two in most of the military vehicles, buses
and helicopters would also be used to facilitate administrative movements of Marines between assembly
areas. Fuel trucks would travel with the main column of vehicles along the primary route and vehicles
would be refueled at the assembly areas. Any major vehicle servicing would take place at MCAGCC and
YPG maintenance facilities. Standard precautions would be taken to prevent fuel and lubricant spills (e.g.,
drip pans/pads laid beneath parked vehicles), and spill kits would be available to cleanup any spills that did
occur.
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2.1.2
EXERCISE ACTIVITIES
The proposed exercise would involve several types of activities, which can be categorized as follows.
Pre-Staging Activities
Pre-staging activities are the operational, logistical, and engineering preparations done prior to initiation of
the exercise or exercise component. For the proposed exercise, these would include the demarcation of sites
to be used during the exercise, posting of public notifications and informational signs, pre-maneuver
biological surveys, positioning of construction equipment at the river crossing area, and pre-positioning of
portable toilets and waste receptacles at the assembly areas. Pre-staging activities would typically involve a
small number (<10) contractor staff and Marine personnel accessing various sites.
Table 2. Vehicles, Watercraft, and Aircraft Used in Exercise.
Mission
Fuel
Type
Humvee/M998
Tactical Maneuver
5-Ton Truck/M923/5
Tactical Maneuver
Type of Vehicle
No. of
Vehicles
Days in
Use
JP8
383
12
JP8
74
12
Highway Vehicles
LAV (Light Armored Vehicle)
Tactical Maneuver
JP8
24
12
LVS (Logistics Vehicle System)
Logistical Support
JP8
20
12
Other Vehicles (buses, contractor vehicles,
etc.)
Troop Transport/ Logistical Support
Varies
45
12
Humvee/M998
Engineering Support
JP8
14
4
5-ton Truck/M923/5 (incl. dump trucks)
Engineering Support
JP8
12
4
MK 48/18 Trailers
Engineering Support
NA
20
4
LVS (Logistics Vehicle System)
Engineering Support
JP8
20
4
592
Total Number of Highway Vehicles
Construction Equipment
Excavator (5-ton)
Engineering Support
JP8
1
4
Compactor (roller)
Engineering Support
JP8
1
4
Front-end loaders
Engineering Support
JP8
2
4
D-7 Dozer (medium dozer)
Engineering Support
JP8
1
4
1150 Dozer (small dozer)
Engineering Support
JP8
1
4
Road Grader
Engineering Support
JP8
1
4
Scraper (18 cu-yd capacity)
Engineering Support
JP8
1
4
Engineering Support
JP8
9
2
Watercraft
Bridge Erection Boats (BEBs)
Bridge Bay Components
Engineering Support
NA
23
2
Avons (Rubber Boats)
Engineering Support
JP8
2
2
KC-130 (airplane)
Logistical Support
JP5
4
7
CH-53E (helicopter)
Troop Transport
JP5
2
4
CH-46E (helicopter)
Troop Transport
JP5
4
3
Aircraft
Staging and Tactical Assembly
Staging and tactical assembly are inter-related and typically occur at the same location. Staging involves
operational and logistical preparations for the tactical maneuvers. Tactical assembly involves the
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administrative gathering of exercise participants and vehicles into established encampments at the end of
daytime maneuvers. In this exercise, areas used for staging and tactical assembly would simply be referred
to as “assembly areas.” (See Desert Scimitar PowerPoint presentation in Appendix for layout of typical
assembly area.)
Initial staging and assembly would take place at MCAGCC during the first days of the exercise. During this
time, participating units would conduct an “administrative road march” (vehicle convoy) from their home
bases to MCAGCC. Upon arrival, the units would be divided among four assembly areas where they would
establish temporary encampments. Vehicle parking and bivouac sites would be arranged so as to minimize
the amount of land occupied.
One or more Combat Operation Centers (COCs) would be setup at each assembly area to serve as a focal
point for administrative and operational activities. A COC site consists of a formation of several vehicles
and temporary shelters to create a protected workspace. Generators would be used to provide electricity
needed to run lights and equipment at the COC. Other areas would be established within the assembly areas
for logistical support activities such as refueling, supply, equipment storage, sanitation, and waste
collection.
While at MCAGCC, Marines would make use of available utilities (e.g., water, electricity) and facilities
(e.g., vehicle maintenance shops), supplemented by portable toilets and waste receptacles provided by
commercial contractors. No mess facilities or fires are required as all meals would be pre-packaged and
ready to eat. Water would be used for drinking and personal hygiene, and portable shower and hand
washing facilities would be provided. Only light maintenance would be performed on vehicles or
equipment at the assembly areas. (Heavy repair or servicing would be done at MCAGCC maintenance
facilities.) Drip pans/pads would be placed under each parked vehicle and spill kits used to cleanup minor
spills.
Off MCAGCC, staging and assembly would be conducted in a similar fashion but with increased
sensitivity to civilian land use and activities in the surrounding area. Water, fuel, and supplies would be
transported to the sites by logistical units. Commercial contractors would provide portable toilets and waste
receptacles. Marine security personnel would work closely with local law enforcement officials to control
traffic, ensure public safety, and protect property in and near the assembly areas. Hand washing facilities
may be established at assembly areas for hygiene.
Initial staging for the Cibola location would also involve the construction of an access ramp at the west
bank of the Colorado River crossing site, commencing on April 18. The BOR-maintained embankment
road downstream from the bridge anchor point would be closed to public access and used as the staging
area for construction activities. For Desert Scimitar 02, the Division would request permission to use a
portion of the Oxbow Recreation Site, located a few hundred yards north of the river crossing site, to
launch boats. The use of the Oxbow Recreation Site will be restricted to no more than 2-4 hours each on
22, 23, and 29 April 2002. At no time will the Oxbow Recreation Site be closed to the public. There will be
no military equipment or personnel staged at the Oxbow Recreation Site. Should any damage occur to the
boat ramp or any other area within the Oxbow Recreation Site, as the result of the exercise, repairs would
be made to restore the original conditions. The Division would work closely with BLM staff and local law
enforcement to ensure that the impact to public recreation is minimized, while ensuring the safety and well
being of citizens and service members. In addition, the Division would coordinate with local law
enforcement to allow recreational access to the river north of the crossing site.
During the bank preparation, the public would be rerouted around the work area and would have full access
to other parts of the river. Riprap and fill material would be excavated from the embankment and
temporarily stockpiled on a portion of the closed roadway. At the same time, the bridgehead and staging
areas on the east side of the river would be prepared to accommodate the bridging equipment used on that
side. The east bridgehead would be taped off by engineers to avoid any accidents by civilians, though
Hippie Hole would remain open to the public during the course of the exercise and the road would remain
open to public travel. Construction activities would be done during daylight hours only. A small contingent
of Marines would occupy the bridgehead and staging sites during the staging period to secure equipment
and ensure public safety.
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Description of the Affected Environment
During the staging and prior to the bridge being erected, Marine units would occasionally use the Cibola
bridge and Farmers bridge (north of Cibola bridge) to move across the river. Marine engineers would
ensure that the weight limits of the bridges are not exceeded. Heavy excavation equipment used on the west
bank would be brought to the site from California Highway 78, heavy equipment on the east bank would be
brought in on Cibola Lake Road or the Ehrenberg-Cibola River Road.
Tactical Maneuvers
For this exercise, the term “tactical maneuver” is limited to mean vehicle travel on highways, paved
secondary roads, or graded (improved) dirt roads. This would include movement or parking on the paved or
graded shoulder of the road, and on any pull-outs, parking lots, and stockpile yards, that are within the
highway right-of-way and maintained for vehicle use. There would be no “off-road” travel, or use of “jeep
trails” or “tracks” during this exercise except within parking sections of assembly areas. No vehicles would
be parked on any berms or mounds so as to avoid desert tortoise burrows. Safety and environmental
protection would be top considerations in all tactical movements. Maximum vehicle speeds would be
limited to 55 mph on highways, 45 mph on other paved roads, and 20 mph on non-paved roads (or less if so
posted).
Tactical maneuvers would take place all along the primary and secondary exercise routes. In addition,
specific maneuver or “engagement” areas have also been designated. There would be no physical
engagement of forces, and no “aggressor” or opposing forces. Engagements would be scripted role-playing
exercises between Marines in the field and commanders at the command centers. The enemy forces would
be imaginary, but the movement and positioning of vehicles in the field would be realistic.
The proposed engagement areas provide the field commanders with greater discretion on where to move
and position their vehicles on authorized roads in order to attain a tactical objective. The Palo Verde
Engagement Area encompasses all of the maintained roads within the Palo Verde Irrigation District
(PVID), south of Interstate 10 (I-10). All state, county, PVID, and approved private roads within this area
could potentially be used in the maneuvers. The Midland Engagement Area encompasses the Midland Rice Road and approved unpaved roads south of Midland town site.
Temporary command posts would be established as field headquarters during daytime maneuvers. A
command post would consist of a small formation of vehicles and shelters, and would be located at a preapproved site in the maneuver area. Command posts would typically be less than 1 acre in size and
occupied by fewer than 20 vehicles (60 persons) at a time. In the Midland Engagement Area, a command
post would be established at the Midland Long-Term Visitors Area (LTVA) and the County Landfill.
At the end of each day (prior to sunset) engagements would stop and the units would retire to their assigned
assembly areas. Nighttime travel would be limited to administrative, logistical support, and emergency
vehicles, and would be on established roads. Vehicle operators would take special care to watch for animals
crossing the roadway during early morning and late afternoon.
Communications
Several radio retransmission sites (“retrans” sites) would need to be established during the exercise. A
retrans operation involves the use of a transreceiver (radio) to receive a signal and retransmit signals over a
desired area of coverage (extending the communications path/distance). The retrans sites in support of
Desert Scimitar 02 would retransmit Single Channel Radio (SCR) in the VHF frequency spectrum (3087.975 MHz) frequency range. The equipment used in these operations consist of VHF SCR radios sets,
both vehicular mounted such as the AN/MRC-145 Radio platform and the portable AN/PRC-119
SINCGARS Frequency Hopping radios. A typical site would have the ability to retransmit anywhere from
3-5 radio circuits, depending on the requirement. The equipment configuration in support of Desert
Scimitar 02 to meet the requirement of retransmitting (3-5 radio circuits) would probably be one (1)
AN/MRC-145 (with the most critical circuit placed on it) and 8-10 AN/PRC-119 portable radios on line
(setup) to cover the additional 3-4 circuits.
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Description of the Affected Environment
Retrans sites would require less than 0.25 acre and would be occupied by one or two Humvees and 3-5
Marines. Most of these retrans sites would be collocated with assembly and staging areas, and command
posts. All others would be collocated with existing communication sites, water towers, and along travel
routes (see figures 27 through 38). RTX 1 in the Ship Mountains would only be accessible by helicopter
(Figure 27). These sites would be setup and operated for the duration of the exercise. At each site,
grounding pits will be dug to ground communications equipment. These will be 30 cm in diameter and
about 10 cm deep and a grounding rod will be inserted up to six feet down. In addition, two pits, one at Iron
Mountain and a second on the Ulmer property will be dug, each measuring about four by six feet across
and two to three feet deep. All of these would be filled with salt which would be removed following the
exercise. The holes would also be re-filled and the pits backfilled. In addition, the Division would request
permission to use areas of high ground aboard YPG to facilitate command and control for this year’s
exercise.
Rafting and Bridging Operation
The crossing of the Colorado River remains a critical element of the exercise. The crossing site at Cibola
was chosen and used during Desert Scimitar 2001 because it accommodates available bridging assets while
protecting the environment. Both sides of the river are managed by the Bureau of Reclamation – Yuma
Area Office and have been highly disturbed and modified by river dredging and filling activities. The west
entry point would require constructing an access ramp into the embankment but the east exit bank would
utilize an existing abandoned boat ramp.
For Desert Scimitar 02, the Division would seek approval to use the BLM Oxbow Recreation Site boat
ramp as appoint for launching and recovering equipment and personnel. Areas around Hippie Hole that are
near to the river crossing activity would be taped off by engineers to avoid any accidents by civilians,
though Hippie Hole would remain open to the public during the course of the exercise.
The Marines plan to transport vehicles, equipment, and personnel across the river using a combination of
rafting and bridging. The floating bridge, called a Ribbon Bridge (MLC 70), would consist of 23 linked
modular components or “bays.” Each of the bay components is 22 feet in length. When several bays are
linked together they can be used as a raft to ferry vehicles across water. The bays are transported on MK
48/18 trailers and are launched directly into the water from the trailers.
Once in the water, the 23 bays are moved about by MKII Bridge Erection Boats (BEBs). These boats are 27
feet in length, weigh 8,000 lbs, and have a crew of three. They are hydrojet propelled and have aluminum
hulls. The boats consume 10.8 gallons of JP8 fuel per hour. The BEBs push the bays from one side of the
river to another. The BEBs are also used in the assembly of the bridge and in maintaining the position of
the bridge against the current.
A rafting and bridging test period would be conducted 22 to 26 April. The rafting and bridging operation
would take place from 0600 to 1800 on 29 and 30 April. On the first day, vehicles would be ferried across
the river on rafts for one hour, then driven across the assembled ribbon bridge for the next 11 hours. On the
second day (30 April 2002), rafting operations would not be conducted. Vehicles would drive across the
bridge from 6 AM to 6 PM. The vehicles exiting the river on the east side would immediately deploy to
their assigned positions in vicinity of Cibola and Ehrenberg.
During the rafting operation, and once the bridge was erected, navigation on the river would be blocked to
civilian watercraft. The bridge could be breached in an emergency, but it would take about 1 hour to do this
safely.
The following operational areas are required for the proposed expeditionary bridge location (a diagram
showing locations of these areas can be seen in the final PowerPoint slide in the Appendix):
·
Staging Area (SA): area for personnel/ equipment to locate awaiting organization of and following
crossing.
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Description of the Affected Environment
·
·
·
·
·
Engineer Regulation Point (ERP): area for engineers to inspect each vehicle prior to it being allowed to
continue on towards/across bridge. This is a requirement only on the West side of the river.
Traffic Control Point (TCP): area for MPs to control the flow of civilian and/or military traffic. This is
a requirement on both sides of the river.
Call Forward Area (CFA): area for unit(s) to move, in a sequenced fashion, towards the crossing site.
This is a requirement only on the West side of the river.
Holding Area (HA): area for unit(s) to be held should the traffic at the crossing site hamper an orderly
crossing. This is a requirement only on the West side of the river.
Engineer Equipment Park on the West side of the river, in the Palo Verde County Park.
Several sites have been identified for use as bridge operational areas. The primary SA on the California
side would be the private land used as assembly areas. Vehicles would wait along the side of a wide, flat
portion of the road--the ERP--near the Palo Verde County Park, until called forward. Traffic control points
and other holding and inspection areas would be located at one of two sites on the California side of the
river. Engineer equipment parks would be established near the bridgeheads on either side of the river, with
most equipment stored on the closed embankment road on the west bank. One D-7 dozier would be located
on the Arizona side of the river, north of Hippie Hole. It would be used as an anchor for the bridge.
Aviation Support
At the end of the exercise, C-17, C-141 and KC-130 airplanes may be used to ferry equipment and
personnel from YPG’s Laguna Army Airfield and MCASY back to MCAGCC and Camp Pendleton. It is
not anticipated that they would be used at the other airfields or airports within or adjacent to planned
assembly areas. Several CH-46E and CH-53 E helicopters would be used to bring cargo and personnel to
MCAGCC, and to move among assembly areas where local conditions permit. Support aircraft would be
available from MCASY or MCAGCC in the case of an emergency. Additionally Marines would seek
approval to land helicopters at the Colorado River Aqueduct airstrip (located in the Iron Mountain Pumping
Station facility), Rice airstrip, Midland airstrip, the Lost Lake borrow pit, private land/assembly areas in
vicinity of Palo Verde and Cibola river crossing site, and aboard YPG along the Cibola Lake Road. Four
helicopters are expected to be used at Iron Mountain, the Blythe Airport, BOR 105, and Felipe Pass on
YPG. All flight patterns would follow established Federal Aviation Administration regulations and no
flights would be below the federally-mandated minimum 500 feet. All movement would be coordinated
with the appropriate air traffic control centers.
2.1.3
EXERCISE ROUTES
The exercise would involve the use of several primary and secondary routes. Auxiliary routes would be
used for administrative movement between sites if needed. These routes are shown in Figure 1.
Primary Route
The primary route consists of highways and improved roads on which large columns of vehicles (200+)
would travel between MCAGCC and YPG. The primary routes would be used both for vehicle convoy and
for tactical maneuvers. During tactical maneuvers, one or more vehicles would park for short-periods along
the graded shoulder of the road (where this could be done safely and legally), on established pullouts and
parking areas within the right-of-way, or at the entrance of small side roads. These areas would be surveyed
for the presence of desert tortoises prior to occupation and useable areas would be delineated with the use
of colored stakes. Tortoise survey techniques are described in the Desert Scimitar Biological Evaluation.
After leaving staging areas at MCAGCC, the majority of units would move southeast along Amboy Road,
National Trails Highway and Cadiz Road (see Figure 3). Units would continue south and east, utilizing
facilities like the Desert Center Airport and Blythe Airport for assembly areas. Continuing south along US
Highway 95 and Highway 78, units would converge on the river-crossing site near the community of
Cibola. After crossing the Colorado River near Cibola, the main column would continue east on to YPG,
Desert Scimitar 02 Exercise
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Description of the Affected Environment
where the exercise would end. Following a brief maintenance period, units would begin administrative
movement back to their original bases.
Secondary Routes
The secondary routes are highways and improved roads leading to, through, or within the staging,
engagement, and assembly areas on which smaller groups of vehicles would travel (30 - 250 vehicles).
These roads would be used as part of the tactical maneuvers. One or more vehicles would park for short
periods along the graded shoulder of the road, on established pullouts and parking areas within the right-ofway, or at the entrance of small side roads. There would be no parking on berms or mounds and these areas
would be surveyed for the presence of desert tortoise.
Auxiliary Routes
Auxiliary Routes would be primarily highways, which are not part of the planned exercise but may be used
if needed to convoy vehicles, and assembly areas on which mostly smaller groups of approximately 30
vehicles would travel, though groups can contain up to 250 vehicles. The auxiliary routes would all be on
paved roads. These include: Highway 78 from I-8 to Palo Verde, Highway 95 from I-8 to YPG, I-10 from
Blythe to Ehrenberg. The auxiliary routes are for transit only and are not included in the environmental
impact analysis.
2.1.4
EXERCISE SITES (ASSEMBLY AREAS, STAGING AREAS, ENGAGEMENT AREAS, AND BRIDGEHEAD)
To facilitate the organization of this EA, the exercise area has been sub-divided into three primary
administrative areas: Arizona, California, and the river crossing (interstate). These have been further
divided into secondary administrative or functional areas. Table 3 lists the sites to be used in Desert
Scimitar 02. The location of the assembly areas are shown in Figure 2.
California
Iron Mountain – Lost Lake Staging Area. This area includes the roads leading from MCAGCC to the
initial off-base assembly areas along or near Highway 62 (see Figures 3 through 5), including the Iron
Mountain, Granite Pass, Rice, and Lost Lake Assembly Areas. Principal roads leading to these areas from
MCAGCC include National Trails Highway, Amboy Road, Iron Age Road, Cadiz Road, Highway 62,
Highway 95. The Iron Mountain Assembly Area is within the Iron Mountain Pumping Station facility
owned and operated by the Metropolitan Water District of Southern California (MWD). It is a developed
area with utilities, potable water, and bivouac sites. The Granite Pass Assembly Area is situated on
disturbed BLM land north of the Highway 62-Highway 177 intersection. The Rice and Lost Lake
Assembly Areas are highly disturbed areas used as borrow pits. The Rice AA is on BLM land and the Lost
Lake AA is situated on the Colorado River Indian Tribes reservation (Figures 3 and 6).
Palen Valley – Milpitas Wash Staging Area. This area extends south of Granite Pass to Desert Center
along Highway 177 and east towards Blythe Airport and south along Wiley Well/Milpitas Wash road to
Highway 78. It includes the Postmile 10 and Desert Center Airport Assembly Areas (see Figures 7 through
10). Postmile 10 is an active Cal Trans stockpile yard along Highway 177. It is highly disturbed. Desert
Center Airport is further south off of Highway 177 on BLM land and has also been highly disturbed by
airport development and agriculture. Upon leaving these two assembly areas, vehicles would travel south
on Highway 78 to the town of Desert Center, then east along I-10 and Chuckwalla Road to the Wiley Well
Road turnoff. Once on Wiley Road, they would proceed south to Milpitas Wash Road to Highway 78, than
north to Palo Verde. Included in this area is the Palen Pass Road turnoff which is about half way between
Granite Pass and Desert Center Airport (Riverside County property). This road would be used to reach the
Arlington Mine Road in Midland Valley on the other side of the range.
Blythe Airport Staging Area. This area includes the Blythe Airport Assembly Area, and roads leading to
city of Blythe and the Palo Verde engagement area (see Figure 11). It includes private property, and
municipal and county land.
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Description of the Affected Environment
Table 3. Sites Used in the Exercise.
State /Assembly Area
Principal Land Use
Ownership/Management
AA Blue (MCAGCC)
Military Training
Marine Corps
AA Red (MCAGCC)
Military Training
Marine Corps
AA Green (MCAGCC)
Military Training
Marine Corps
CALIFORNIA
AA Black (MCAGCC)
Military Training
Marine Corps
AA Granite Pass
Open Space
Bureau of Land Management
AA Iron Mountain
Water Pumping Station
Metro. Water District
AA Rice
Borrow Pit / Open Space
Bureau of Land Management
AA Desert Center Airport
Airport / Open Space
Riverside County
AA Postmile 10
Highway Stockpile
Bureau of Land Management
AA Lost Lake
Borrow Pit
Colorado River Indian Tribes
AA Midland
Former Town Site
US Gypsum
AA Midland LTVA
Recreation
Bureau of Land Management
AA Landfill
Sanitary Landfill
Riverside County
AA Blythe Airport
Airport / Open Space
Riverside County
AA Sieler Stack Yard
Agriculture
Private Property
AA Ulmer Family Field
Agriculture
Private Property
AA Ulmer Stack Yard
Agriculture
Private Property
AA Wuertz Property
Agriculture
Private Property
AA Schindler Property
Agriculture
Private Property
AA Palo Verde County Park
Recreation
Imperial County
Oxbow Recreation Site
Recreation
Bureau of Land Management
Residential Boat Ramp
Residence
Leased BLM Property
West Bridgehead
River Maintenance
Bureau of Reclamation
River Maintenance
Bureau of Reclamation
ARIZONA
East Bridgehead
BOR Dredge Slip (Hippie Hole)
River Maintenance
Bureau of Reclamation
AA BOR 98
Maintenance Stockpile
Bureau of Reclamation
AA BOR 105
Maintenance Stockpile
Bureau of Reclamation
AA Ehrenberg
Recreation
Bureau of Land Management
AA Roadrunner
Recreation
Bureau of Land Management
AA Sites 13-35 (YPG)
Military Testing and Training
Army Yuma Proving Ground
AA Felipe Pass (YPG)
Military Testing and Training
Army Yuma Proving Ground
AA Sites 1-12 (YPG)
Military Testing and Training
Army Yuma Proving Ground
AA Cibola C-17 (YPG)
Military Testing and Training
Army Yuma Proving Ground
AA Castle Dome Annex (YPG)
Military Testing and Training
Army Yuma Proving Ground
Midland Engagement Area. This area includes the Midland-Rice Road from Rice to Midland and south to
Blythe, and maintained dirt roads within the Midland valley that would be approved for use by the BLM.
Most of the land on either side of the Midland-Rice Road belongs to the BLM, including the Midland
Long-Term Visitors Area. The Assembly Area near the Midland town site is owned by US Gypsum. The
Landfill south of the Midland LTVA is owned and operated by Riverside County. The Midland town site,
LTVA, and Landfill would each be used as an Assembly Area (see Figures 12 and 13).
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
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Description of the Affected Environment
Palo Verde Engagement Area. This area encompasses all the land and roads within the Palo Verde
Irrigation District south of I-10. Most of the proposed exercise would take place on state, county and PVID
roads within the agricultural area. Assembly Areas have been established on several private properties:
Sieler Stackyard, Ulmer Family Field and Stackyard, the Wuertz Property, and the Schindler Property, and
on the Palo Verde County Park, located along Highway 78 (Figure 14).
Arizona
Quartzsite-Cibola Staging Area. This area includes all project sites in Arizona, outside of YPG. It
includes the routes from the river to the west and east borders of YPG: Cibola Lake Road, River Road, I10, Tom Wells Road, Ehrenberg Wash Road (an established, graded road that travels within a wash before
entering YPG), and Highway 95. The routes pass through BLM, BOR, State of Arizona, and privately
owned property. Vehicles will not travel off these roadways and no stops would be planned; if a breakdown occurred, it would be handled on the road surface. Proposed assembly areas in this area include the
BLM Roadrunner 14-day use area south of Quartzsite (herein referred to as the Roadrunner Assembly Area
, the public lands east of Ehrenberg (herein referred to as the Ehrenberg Assembly Area), and the BOR
stockpile sites, near Cibola (known as the BOR 98.9 and BOR 105.3 Assembly Areas). Refer to Figures 15
through 19 for these areas.
YPG Staging Area. This area encompasses the primary exercise route within the borders of YPG, and all
sites on YPG. The primary route includes a portion of US Highway 95 and that part of Cibola Lake Road
that passes through the installation. These are shown in Figures 20 through 26. Yuma Proving Ground is
administered by the US Army. The YPG portion of this proposed exercise is covered under existing YPG
environmental documents and authorizations (USAYPG 1998).
River Crossing Area
East and West Bridgeheads. The Lower Colorado River crossing site spans two states and multiple
jurisdictions. The BOR administers the land on either side of the river crossing. The BLM Yuma Field
Office is responsible for managing public lands near to the river on both the Arizona and California side.
The Army Corps of Engineers, US Coast Guard, and state wildlife agencies have jurisdiction along the
banks and in the channel. Under DM 613, the BLM-Yuma has management responsibility for some BOR
withdrawn or acquired lands. Traffic Control Points (TCPs) at the river crossing are shown in Figure 39.
About a half a mile north of the proposed river crossing site is the Oxbow Recreation Site, managed by the
BLM Yuma Field Office. This pay-for-use campground has restrooms, waste facilities, and a boat ramp, all
of which will remain open to the public. The campground serves as a local hub for fishing and wildlife
viewing year round, and for power boating and jet-skiing during the warmer summer months; it will not be
used as a staging area by the Marines. The Marines have developed a fire plan to address any wildfires in
these BLM-managed areas (USMC, 2002).
A levee road along the west bank of the Colorado River would be temporarily closed to traffic southward
from the bridge anchor points to accommodate and protect the floating bridge anchor points and the new
access point. All portions of the east side levee road would remain open to the public with the exception of
a corridor from the levee road to east bank bridge connection point. That point would be taped off from the
public use area and would be used on April 29 and 30 to provide access to the floating bridge.
The oxbow boat ramp would be a convenient place to launch and land the boats and the 23 floating bridge
bays used to support the Desert Scimitar river crossing. Testing of the launch procedure would be
conducted at the oxbow ramp during two-to-four hour periods on 22, 23, and 29 April. Only on 29 and 30
April will the river would be closed to public use from the northern boundary of Cibola Refuge to the
Cibola Bridge.
Desert Scimitar 02 Exercise
Twentynine Palms, CA to Yuma, AZ
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
Radio Retransmission Sites
Radio retransmission sites would be established at several locations in the project area (Table 4). Many of
these sites would be co-located with proposed Assembly Areas. For the retransmission sites outside of the
Assembly Areas, see Figures 27 through 38. Each site would be occupied both day and night by small units
of Marines.
Table 4. Radio Retransmission Sites.
2.1.5
Site Number
Site Code
State Location
Latitude
Longitude
Site 1
11SQ554812
AZ
YPG-CDH
N 32 Deg 58 Min
W 114 Deg 17 Min
Site 2
11SQT067227
CA
McCoy Mt. Radio Facility
N 33 Deg 36 Min
W 114 Deg 46 Min
Site 3
11SQ2554812
AZ
Stone Cabin
N 32 Deg 15 Min
W 114 Deg 14 Min
Site 4
11SQS519928
AZ
YPG C-17
N 33 Deg 20 Min
W 114 Deg 17 Min
Site 5
11SQT123215
CA
Blythe Airport
N 33 Deg 37 Min
W 114 Deg 43 Min
Site 6
11SQT196319
CA
Co. Landfill, Midland Rd.
N 33 Deg 42 Min
W 114 Deg 37 Min
Site 7
n/a
CA
I-10 x CA Hwy 177
N 33 Deg 38 Min
W 115 Deg 10 Min
Site 8
n/a
CA
Granite Pass
N 34 Deg 04 Min
W 115 Deg 14 Min
Site 9
11SQG429989
AZ
Cibola
N 33 Deg 24 Min
W 114 Deg 23 Min
Site10
11SPU290055
CA
Retrans1
N 34 Deg 23 Min
W 115 Deg 35 Min
Site11
11SPT893821
CA
Main
N 34 Deg 09 Min
W 114 Deg 56 Min
Site12
11SPT572269
CA
Desert Center
N 33 Deg 40 Min
W 115 Deg 18 Min
Site13
11SQT005259
CA
Blythe
N 33 Deg 39 Min
W 114 Deg 50 Min
Site14
11SNU862235
CA
AA Red
N 34 Deg 33 Min
W 116 Deg 03 Min
Site15
11SPT727785
CA
AA Iron Mountain
N 34 Deg 07 Min
W 115 Deg 07 Min
Site16
11SPU039096
CA
AA Blue
N 34 Deg 25 Min
W 115 Deg 52 Min
Site17
11SNU938200
CA
AA Black
N 34 Deg 31 Min
W 115 Deg 58 Min
Site18
11SQT092002
CA
Palo Verde
N 33 Deg 25 Min
W 114 Deg 45 Min
Site19
11SQT108502
CA
Main/Fwd
N 33 Deg 52 Min
W 114 Deg 43 Min
Site20
11SQS479993
AZ
Cibola Retrns
N 33 Deg 24 Min
W 114 Deg 20 Min
Site21
11SQS552956
AZ
Cibola Assembly Area
N 33 Deg 22 Min
W 114 Deg 15 Min
Site 22
11SQT2940037400 CA
Big Maria Mountains
N 33 Deg 45 Min
W 114 Deg 31 Min
Site23
11SQT160419
AA Landfill
N 33 Deg 47 Min
W 114 Deg 40 Min
AZ
SCHEDULE OF ACTIVITIES
The planned daily activities for Desert Scimitar 02 are described below. A pictorial account is presented in
the Appendix (1st Marine Division PowerPoint brief of 11 Jan 02).
15-21 April: Pre-Staging Activities
An Advanced Party would begin preliminary activities at MCAGCC during the week before the exercise
begins. This group includes communicators, Motor Transport Marines, and logisticians who would prepare
for the main body’s arrival on April 22. Engineering gear and 75 personnel would move to the Palo Verde
County Park by 17 April. On 18 and 19 April, six boats would be launched into the river, one from the
Oxbow ramp and five from Harvey's Fishing Hole/Sportsman’s Paradise (on private land on the west
bank).
22-24 April: Staging at MCAGCC Assembly Areas
Nearly Six hundred vehicles would convoy from Camp Pendleton, MCAGCC, and Port Hueneme to
MCAGCC assembly areas. Standard convoy traffic control procedures would be followed. Vehicles would
Desert Scimitar 02 Exercise
Twentynine Palms, CA to Yuma, AZ
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
travel in groups of 10 or fewer and not exceed 55 miles per hour on the highway; most would travel
between the hours of 1400 and 1900. The majority of Marines would be transported to MCAGCC in these
vehicles while some would be airlifted to MCAGCC by airplane or helicopter. Once at MCAGCC Marines
would spend the first three days of the exercise on MCAGCC conducting staging and assembly activities in
preparation for the subsequent tactical maneuvers and river crossings. There would likely be increased
traffic during this time as administrative and logistical support vehicles moved between assembly areas.
Also at this time, engineering units at the river crossing site would construct the access ramp in the west
embankment and prepare the bridgehead sites for the bridging operation. Bridging materials and equipment
would be positioned at the Palo Verde County Park. A small amount of raft and boat training would be
conducted on the river. This daylight training would not close the river nor would it interfere with civilian
recreational activities..
25-26 April: Movement to Contact
Upon order to advance, all vehicles would exit MCAGCC and begin to move south and east toward the
designated river crossing sites. A small amount of raft and boat training would be conducted on the river.
This daylight training would not close the river nor would it interfere with civilian recreational activities.
27-28 April: Seize Near-Shore Objectives and Shaping
Approximately 300 vehicles would converge in the vicinity of Palo Verde, in preparation to cross the
expeditionary bridge at Cibola. Another 100+ vehicles would stage in the vicinity of the Ulmer property.
29 April to 1 May: River Crossing
At 6AM, Marine engineers will launch bridge components from the west bank access point. Rafting and
bridging operations will begin shortly after 6AM on April 29. Vehicles that have the capability to “swim”
across the river would simulate this process by crossing the Farmer’s bridge (none of these vehicles exceed
the weight capacity of that bridge). Bridge components would be launched from the west bank. Once on the
opposite side of the river, units would continue to move toward the eastern portion of Yuma Proving
Grounds in the vicinity of the C-17 Airfield. Crossing operations would cease at dusk, and the engineers
would disassemble the bridge; they would reassemble the bridge in the morning, and resume river-crossing
operations. The river would be closed to public use on April 29 and April 30 from the northern boundary of
Cibola Refuge to the Cibola Bridge. After the river crossing is completed, the engineering units would
disassemble and haul away the bridge components. An access point would be constructed at the west
embankment but any other modifications would be returned to original conditions as much as possible. At
the request of BOR, Yuma the west bank river access point would remain in place following the exercise.
BOR, Yuma would assume control of the access point following the exercise and would install fencing to
control its use.
2-3 May: Staging for Retrograde/End of Exercise YPG
Once all vehicles arrive in the vicinity of the C-17 airstrip, the tactical portion of the exercise is complete.
An after action review would commence in the field, and Marines would perform any necessary
maintenance prior to returning to their bases of origin. All vehicles would conduct an administrative move
along major highways, using the same convoy procedures that were used to get the units to MCAGCC.
Table 5 shows the night time location of the vehicles during the exercise. Table 6 shows the number of
vehicles per route segment per task force group.
4-10 May: Post-Exercise Activities
Marine engineers would stay on site until all post-exercise activities and site inspections have been
completed. These activities would include any clean up at the bridgehead area such as equipment removal
and replacement of disturbed soils; gathering of flagging and posting materials, and toilets; removal of salt
and filling of holes at radio grounding sites; and amending ground disturbance at assembly areas and dayuse sites.
Desert Scimitar 02 Exercise
Twentynine Palms, CA to Yuma, AZ
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
Table 5. Vehicle Location at the End of Each Day of the Desert Scimitar 02 Exercise.
Days from Start of Exercise
5
6
7
8
9
10
Total
Days
1
2
3
4
AA Blue (MCAGCC)
157
157
157
30
AA Red (MCAGCC)
319
319
319
3
CALIFORNIA
4
AA Green (MCAGCC)
66
66
66
3
AA Black (MCAGCC)
25
25
25
3
AA Granite Pass
127
AA Iron Mountain
253
AA Rice
157
1
228
2
1
AA Des. Center/Postmile 10
66
1
AA Lost Lake
18
AA Midland
131
AA LVTA
147
1
AA Landfill
43
1
AA Blythe Airport
1
70
144
AA Sieler Stack Yard
AA Ulmer Family Field
148
AA Ulmer Stack Yard
2
125
2
105
1
130
2
66
1
AA Wuertz Property
0
AA Schindler Property
AA Palo Verde Rest Area
139
25
25
25
25
25
25
1
25
33
123
122
25
25
10
ARIZONA
AA BOR 98
0
AA BOR 105
AA Ehrenberg
65
AA Roadrunner
43
AA Sites 13-35 (YPG)
18
2
1
18
2
206
2
AA Felipe Pass (YPG)
105
1
AA Sites 1-12 (YPG)
18
AA Cibola C-17 (YPG)
AA Castle Dome Annex (YPG)
Total Vehicles
Desert Scimitar 02 Exercise
Twentynine Palms, CA to Yuma, AZ
1
531
567
18
592
592
592
19
592
592
592
592
592
592
2
1
592
Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
Table 6. Desert Scimitar 02 Route Segments by Task Force.
Approx.
Miles
Origin - Destination
Route Segment
Total Number of Vehicles Transiting Road by Task Force Group,
Days 1-10
un1
3
11
paved paved TF1 TF7 TF23 LAR LAR TFT MCP FCP MP DEG 7ESB Total
85
10
20
45
Power line Rd to Hwy 62
MCAGCC
NTH-Amboy RdIron Age Rd-Hwy
62
NTH-Cadiz RdPower line Rd
Cadiz Rd
0
20
101
Granite/Iron Mt to Cadiz Rd
Hwy 62
10
0
101
Cadiz Rd to Rice
Hwy 62
5
0
Granite Pass/Iron Mt to Palen
Pass Rd
Palen Pass Rd to Desert
Center/ Postmile 10
Hwy 177 to Midland-Rice Rd
Hwy 177
10
0
66
10
0
66
MCAGCC to Granite/Iron Mt
101
139
101
66
18
66
18
18
25
122
40
30
139
18
139
18
25
122
8
25
8
40
30
40
223
298
8
18
18
592
344
40
122
139
30
301
157
25
109
Hwy 177
66
0
35
60
40
25
10
18
Lost Lake to Midland Rd
Palen Pass RdArlington Mine Rd
Hwy 177-Chuck
walla Rd-I10WWMWR-Hwy78
Hwy 62-Vidal RdHwy 95
Hwy 95-I10-MRR
45
0
18
Rice to Midland
MRR
0
20
101
139
122
30
40
8
440
Midland to Arlington Mine Rd
MRR
5
0
101
139
122
30
40
8
440
Arlington Mine Rd to
LTVA/Landfill
LTVA/Landfill to I-10
MRR
5
0
101
139
18
25
122
30
40
8
483
MRR
5
0
101
139
18
25
122
30
40
8
483
Midland-Rice Rd to Hwy 78
I-10
5
0
101
139
25
122
30
40
8
Hwy 78 to Blythe Airport
I-10
5
0
101
I-10 to Palo Verde
Hwy 78
20
0
101
139
66
18
18
25
122
30
40
8
567
Palo Verde to River
Crossing/BOR 98
River Crossing/BOR 98.9 to
BOR 105
Hwy 78-Access
Rds
River Road
5
0
101
139
66
18
18
25
122
30
40
8
567
139
66
18
122
30
40
8
Desert Center/ Postmile 10 to
Palo Verde
Rice to Lost Lake
18
25
43
66
66
18
18
18
18
18
25
30
501
174
5
0
CLR
0
5
5
20
Ehrenberg to Roadrunner
River Rd-I10-Tom
Wells Rd
I10-Hwy 95
15
0
Ehrenberg to Felipe Pass
RWEWR
0
25
BOR 105.3 to Sites 12-35
CLR
0
15
101
139
Sites 12-35 to Felipe Pass
CLR
0
10
101
139
Felipe Pass to Sites 1-11
CLR
0
5
101
139
66
Sites 1-11 to Cibola (C-17)
CLR -Access Road
0
5
101
139
66
18
25
Cibola (C-17) to Hwy 95
CLR
0
5
18
18
25
61
Roadrunner to CLR
Hwy 95
20
0
18
25
43
Hwy 95
30
0
Total
405
270
BOR 105.3 to Ehrenberg
CLR to Castle Dome Annex
101
139
25
18
66
248
458
18
25
109
18
25
43
66
66
18
122
30
40
8
458
18
122
30
40
8
458
18
122
30
40
8
524
122
30
40
8
549
18
18
NTH = National Trails Highway, MRR = Midland-Rice Road; CLR = Cibola Lake Road; TWEWD = Tom Wells/Ehrenberg Wash Road;
WWMWR = Wiley Well/Milpitas Wash Road
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
2.2
REDUCED ROUTE ALTERNATIVE
This alternative would be identical to the Proposed Action except that it would eliminate certain unpaved
segments of the travel routes. The objective of this alternative would be to reduce dust emissions caused by
vehicle travel on unpaved roads.
Specifically, the alternative would eliminate use of:
·
·
·
Cadiz Road (vehicles would travel on the Amboy Road-Iron Age Road-Highway 62 route to reach the
Iron Mountain Assembly Area).
Palen Pass / Arlington Mine Road (vehicles would use Highway 177 – I-10 – Midland-Rice Road to
reach Midland, LTVA, and Landfill Assembly Areas).
Wiley Well/Milpitas Wash Road (vehicles would use I-10 – Highway 78 to reach the Assembly Areas
near Palo Verde and the river crossing site).
All other dirt road sections in California would stay in the route plan. All unpaved routes in Arizona,
including River Road, Tom Wells/Ehrenberg Wash Road, and Cibola Lake Road would be retained.
2.3
BOAT LAUNCH ALTERNATIVE
This Boat Launch Alternative would be identical to the Proposed Action (or the Reduced Route
Alternative) but would eliminate the use of the BLM Oxbow Recreation Site for BEB launching/landing.
The objective of this alternative would be to reduce potential negative impacts to recreational users wishing
to use the Oxbow campground or boat ramp during the bridge preparation and construction period.
Two optional boat launch locations are considered:
Option 1: launch/land BEBs from the east bridgehead of the river crossing site (as was done during Desert
Scimitar 01). Bridging materials would be staged at BOR sites near the bridgehead.
Option 2: launch/land BEBs from existing boat ramp located in a residential area approximately 4 river
miles upstream from the proposed river crossing. Boat equipment would be stored at BOR sites near the
bridgehead.
2.4
NO ACTION ALTERNATIVE
Under the No Action alternative, authorization through the BLM cooperative agreement would not be
issued to the Marines for this exercise. The 1st Marine Division Desert Scimitar 02 exercise would take
place at MCAGCC and/or YPG where these military exercises are currently permitted.
2.5
ALTERNATIVES ELIMINATED FROM FURTHER CONSIDERATION
Several alternatives were considered during the initial planning phase of the exercise but were eliminated
because they either did not meet 1st Marine Division’s training needs or would likely involve negative
impacts on the human environment. These alternatives included:
a)
Conducting Desert Scimitar 02 solely on military lands in the area. As discussed in the Purpose and
Need section of this EA, the limited size of MCAGCC, YPG, and other military lands in the area do
not allow the 1st Marine Division to meet its command and communication training needs. Nor do
existing military installations allow for deployment of a floating bridge to test river crossing
capabilities. The combination of geography, hydrology, and human land use, and the proximity to
existing military lands were all considered in the planning process before choosing the current project
area. Also see the Appendix of PowerPoint slides, especially the slide entitled “Why conduct training
off base”.
Desert Scimitar 02 Exercise
Twentynine Palms, CA to Yuma, AZ
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
b) Conducting Desert Scimitar 02 in the Imperial Valley. This alternative was eliminated early in the
planning process because of the high population density in the El Centro area. It also did not provide
for a river crossing site.
c)
Changing the date of the exercise. The date for the exercise was planned far in advance. The date is
integrated into the Divisions long-term planning schedule and cannot be changed this year. The timing
of key elements of the exercise, such as the weekday river crossing, were chosen specifically to
minimize impact on recreational users of the river.
d) Reducing the size and extent of the exercise. The proposed Desert Scimitar project area represents an
optimal size for this exercise, consistent with the requirements of the Marines operational plans. The
rural nature of the area, and the distribution of travel routes and potential assembly areas allows for an
appropriate level of tactical maneuver. Reduction in the number of Marines or vehicles would reduce
the effectiveness of the training mission. The number of Marines and vehicles, 2,200 and 600
respectively, represents the upper limit of what the 1st Marine Division could deploy for a training
mission of this type.
2.6
PERMITS AND APPROVALS
Permits and authorizations required to implement the Proposed Action or Modified Action Alternative are
shown in Table 7.
Table 7. Permits and approvals.
Permits / Approvals
Permitting Agency / Party
Section 404 (Clean Water Act), Nationwide 12 Permits
US Army Corps of Engineers (USACE)
Section 7 Consultation (Endangered Species Act)
US Fish and Wildlife Service (USFWS)
Section 106 Consultation (National Historic Preservation Act)
State Historic Preservation Officer (SHPO)
Water Quality Certification or Waiver (Section 401)
California Regional Water Quality Control Board (RWQCB)
Section 1603 Streambed Alteration Agreement
California Department of Fish and Game (CDFG)
Section 2081 (California Endangered Species Act) Incidental
Take Permit
California Department of Fish and Game
Encroachment Permits
Cal Trans
Encroachment Permits
Arizona Department of Transportation (ADOT)
Right of Use Permit
US Bureau of Reclamation (BOR)
Bridge Permit
US Coast Guard (USCG)
Letter of Intent to Use (Blythe Landfill)
Riverside County
Letter of Intent to Use (Desert Center Airport)
Riverside County
Park Facility Activity (Palo Verde Campground)
Imperial County Parks and Recreation
Environmental Agreement for Training Units Operating at YPG
US Army Yuma Proving Ground (YPG)
Use Permit
Metropolitan Water District of Southern California
Use Permit
Colorado River Indian Tribes
Cooperative Agreement Between BLM and USMC
BLM – Palm Springs Field Office
Property Use Permit
US Gypsum
Property Use Permit
Ulmer Property Owner
Property Use Permit
Schindler Property Owner
Property Use Permit
Seiler Property Owner
Property Use Permit
Wuertz Property Owner
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Description of the Affected Environment
3.0
DESCRIPTION OF THE AFFECTED ENVIRONMENT
This section briefly describes the existing natural and cultural resources within the project area potentially
affected by the Proposed Action and Alternatives. The existing conditions constitute the baseline for
assessing potential impacts of the Desert Scimitar 02 exercise.
3.1
SPECIAL MANAGEMENT AREAS
3.1.1
ACECS
Areas of Critical Environmental Concern (ACECs) are public lands requiring special management to
protect and prevent irreparable damage to important historic, cultural, or scenic values; fish and wildlife
resources; and other natural systems or processes. In California, the proposed exercise route passes near to
the following ACECs: Amboy Crater (south of Amboy Road), Marble Mountain Fossil Bed (east of Cadiz
Road), Desert Lily Sanctuary ACEC (east of California Highway 177), Alligator Rock ACEC (south of
Desert Center), Palen Dry Lake ACEC (north of I-10), Chuckwalla Valley Dune Thicket (south of I-10)
and the (BLM 2001). In Arizona, no ACECs occur within the vicinity of the proposed project route or
activity (BLM 1994, BLM 1996b). No proposed activities take place within ACECs. The project would
pass through the Milpitas Wash Special Management Area, in California.
3.1.2
LONG-TERM VISITOR AREAS (LTVAS)
Long-Term Visitor Areas (LTVAs) are special campgrounds developed to fulfill the needs of winter
visitors and to protect the local desert ecosystem from overuse. In California, the Midland LTVA occurs
along the exercise route adjacent to the Midland - Rice Road. Under the Proposed Action, a small portion
of this site would be used as an assembly area. In Arizona, the proposed exercise route would pass through
but not use the La Posa LTVA (on either side of US Highway 95, south of Quartzsite) (BLM 1996b). An
overnight assembly area would be established at the Roadrunner Assembly Area located along the
southwest corner of the La Posa LTVA.
3.1.3
WILD AND SCENIC RIVERS
No designated wild and scenic rivers are within the proposed project area.
3.1.4
WILDERNESS AREAS
The proposed exercise route travels near to but not within any designated wilderness areas (BLM 1995). In
California, these include: Sheephole Valley Wilderness (east of Amboy Road), the Cleghorn Lakes
Wilderness (west of Amboy Road), the Trilobite Wilderness (north of National Trails Highway), Cadiz
Dune Wilderness (west of Cadiz Road), Old Woman Mountain Wilderness (east of Cadiz Road), Joshua
Tree Wilderness (west of Highway 177), Palen/McCoy Wilderness (east of Highway 177, west of MidlandRice Road, north and south of Palen Pass/Arlington Mine Road, and north of I-10), Chuckwalla Mountain
Wilderness (south of I-10), Turtle Mountains Wilderness (north of Rice), Rice Valley Wilderness (east of
Midland-Rice Road), Big Maria Wilderness (east of Midland-Rice Road), Riverside Mountain Wilderness
(west of Highway 95), and Palo Verde Mountains Wilderness (west of Highway 78, and south and east of
Wiley Well and Milpitas Wash Roads). The Palen Pass road is bordered on either side of the roadway by
wilderness.
In California, the Big Maria communications site would be located near the boundary of the Big Maria
Wilderness. In Arizona, the proposed route will be a few miles west of the Kofa Wilderness (east of
Highway 95).
3.1.5
DESERT TORTOISE CRITICAL HABITAT
In 1994 the US Fish and Wildlife Service designated 6.4 million acres of critical habitat for the Mojave
population of the desert tortoise (DTRT 1994). In California, the proposed exercise route travels near to, or
Desert Scimitar 02 Exercise
Twentynine Palms, CA to Yuma, AZ
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
on paved highways through, three designated critical habitat areas: the Chemehuevi Unit (south of I-40 and
north of Highway 62), the Chuckwalla Unit (south of I-10 and Desert Center), and the Pinto Mountain unit
(south of California Highway 62 between Granite Pass and Twentynine Palms).
3.1.6
NATIONAL WILDLIFE REFUGES AND NATIONAL PARKS
The proposed exercise route would pass just to the east, and again to the north, of Joshua Tree National
Park in California. On the Arizona side, the proposed exercise route passes just north of the Cibola National
Wildlife Refuge (NWR). The east bank of the river crossing site (Arizona side) lies about one quarter mile
north of the Cibola NWR. Vehicles traveling south on Highway 95 between Quartzsite and the Castle
Dome Annex (YPG) would come within one-half mile of the west boundary of the Kofa Wildlife Refuge.
3.1.7
FARMLANDS AND FLOODPLAINS
The proposed exercise route passes through the Lower Colorado River floodplain and developed farmlands
of the Palo Verde Valley. Certain farmland properties would be used as assembly areas by permission of
the private property owner.
3.2
GEOLOGY AND SOILS
The project area is located in the Basin and Range physiographic province, characterized by northwest to
southeast trending mountains separated by broad alluvial basins. (USMC 1997). The mountain ranges are
formed of Precambrian to Tertiary igneous, metamorphic, and sedimentary rocks. The valleys or basins
consist of thick, unconsolidated to weakly consolidated silts, sands, clays, and gravels. Alluvial and
colluvial deposits form alluvial fans along the mountain bases. The region is rich in mineral resources and
many active and abandoned mines occur in the area (BLM 1987, BLM 1999, USAYPG 1998). Soils vary
throughout the project area, ranging from fine-grained sands and silts on the valley floors to very gravelly
soils in the mountain regions (USMC 1997). Historic and contemporary off-road vehicle travel in the
project area has caused accelerated soil erosion and land degradation in many areas (BLM 1987, BLM
2001, USAYPG 1998).
3.3
WATER QUALITY
Precipitation in the project area ranges from 5 to 10 inches per year, most of it occurring in mid-winter and
in the late summer, often as intense rainfall (USMC 1997). Surface runoff flows to closed alluvial basins or
to tributaries of the Lower Colorado River. Groundwater occurs in the deep alluvial basins between
mountain ranges. Depth to groundwater is only a few feet near the Colorado River but can be several
hundred feet in the uplands away from the River (USAYPG 1998). Perennial surface water occurs in only a
few places in the project area, most notably in and near the Colorado River. Surface water can also be
found at springs, tinajas (natural rock pools), wells, livestock tanks, wildlife guzzlers, irrigation canals, and
in above-ground portions of the Colorado River Aqueduct (BLM 1987, BLM 1999, USAYPG 1998).
Ephemeral flows in desert washes provide a vital source of soil moisture for xeroriparian plant
communities. Water diversions, bank stabilization and other channel modifications, flood releases, and
development in the floodplain have resulted in the historic decline in wetland and riparian habitats along
the River (USFWS 1997).
The Lower Colorado River is a highly modified and regulated river system. Flows are controlled by a series
of dams and large quantities of water are diverted for agricultural and municipal use (USFWS 1997). The
Palo Verde Irrigation District is a major consumptive user of river water within the project area. River
discharge and stage can vary considerably during the day as water is released from the dams to meet water
supply and power demands. Construction and maintenance of dams and channel structures are the primary
factors affecting water quality in the Lower Colorado River (USFWS 1997). Other factors which may
potentially decrease water quality are municipal effluent discharge, stormwater runoff, agricultural
drainage, and increased recreational use.
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Description of the Affected Environment
3.4
TRANSPORTATION AND ACCESS
The proposed project area has an established system of primary and secondary roads, and can be entered
through multiple access points. Several high-speed highways cross the area: I-10, US Highway 95 (in both
California and Arizona), and California Highways 78, 177, and 62. Other major paved roads include
National Trails Highway, Amboy Road, Chuckwalla Road, and southern half of Midland-Rice Road. The
Palo Verde Irrigation District encompasses an extensive network of farm and irrigation roads. Several
improved dirt roads are maintained for public use in the project area, including: Cadiz Road, Iron Age
Road, northern part of Midland-Rice Road, Arlington Mine Road, Wiley Well/Milpitas Wash Road, River
Road, Tom Wells Road, and Cibola Lake Road. Other established roads such as Palen Pass Road and
Ehrenberg Wash - Felipe Pass trail are less frequently maintained. Levee and embankment roads, and
numerous lateral access roads, provide access to the proposed crossing site on the Lower Colorado River.
Numerous improved and primitive dirt roads cross the project area. The proliferation of roads on public
lands has been a major management issue for the BLM in both Arizona and California (BLM 1987, BLM
2001).
3.5
AIR QUALITY
The Clean Air Act established National Ambient Air Quality Standards (NAAQS) for pollutants that may
cause adverse health effects. The pollutants of concern are sulfur dioxide (SO2), carbon monoxide (CO),
nitrogen dioxide (NO2), particulate matter less than 10 microns in diameter (PM10), particulate matter less
than 2.5 microns in diameter (PM2.5), ozone, and lead. In most cases the states have adopted the Federal
NAAQS as the state AAQS. However, California has developed more stringent standards for selected
pollutants. California has also adopted AAQS for hydrogen sulfide, sulfates and visibility. Table 9 lists the
Federal and California AAQS. Table 10 lists the California AAQS for pollutants that have no comparable
NAAQS. Areas that exceed the NAAQS and AAQS are designated as non-attainment areas.
The US EPA and the California Air Resources Board (CARB) have determined the attainment status of all
areas of California. Information from these agencies indicates that the California area of this exercise is in
attainment for SO2, CO, NO2 and lead. The California area of this exercise is in attainment for the ozone
and PM10 NAAQS while it is in non-attainment for the State AAQS for these pollutants.
Arizona has adopted the NAAQS (ADEQ 2001a) as the State AAQS. The US EPA has also determined the
attainment status of Arizona. The Arizona portion of this exercise is generally in attainment for all NAAQS
except for a small portion of the YPG, which exceeds the PM10 standard (USMC 1997, USAYPG 1998).
Air quality in the La Posa/Roadrunner Assembly Area was found to be generally good, although periods of
exceedance of Arizona AAQS have occurred near Quartzsite (BLM 1996b).
The PM2.5 and eight-hour ozone NAAQS are relatively new and were the subject of a court case. The US
Supreme Court recently upheld the US EPA’s position regarding their legal authority to issue these
standards. The US EPA has not issued official attainment status designations for either of these standards.
Impact to visibility from pollutants transported from major urban centers is likely and, when present,
frequently impairs visibility in the vicinity of the Joshua Tree National Park (BLM 2001). Local pollution
sources in the Desert primarily comprise particulate matter from off-road vehicles, windblown soil, mining
operations, and agricultural activities.
Imperial County APCD: The eastern portion of Imperial County (proposed exercise route) is in attainment
for PM10 and ozone NAAQS and non-attainment for the California AAQS. Imperial County is located
within the jurisdiction of the Imperial County Air Pollution Control District. A small portion of the
proposed exercise route would fall under the jurisdiction of the ICAPCD.
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Description of the Affected Environment
Table 8. Federal and state ambient air quality standards.
Pollutant
Averaging
Time
California Standards
1 Hour
0.09 ppm (180 µg/m3)
8 Hour
---
0.08 ppm (157
µg/m3)
Annual
Geometric
Mean
30 µg/m3
---
24 Hour
50 µg/m3
150 µg/m3
Annual
Arithmetic
Mean
---
50 µg/m3
Ozone (O3)
Respirable
Particulate
Matter (PM10)
Fine
Particulate
Matter
(PM2.5)
Carbon
Monoxide
(CO)
Nitrogen
Dioxide
(NO2)
Lead
Sulfur
Dioxide (SO2)
Federal Standards
Primary
0.12 ppm (235
µg/m3)
Secondary
Same as Primary
Standard
Same as Primary
Standard
65 µg/m3
24 Hour
Same as Primary
Standard
Annual
Arithmetic
Mean
No Separate State
Standard
15 µg/m
8 Hour
9.0 ppm (10 mg/m3)
9.0 ppm (10 mg/m3)
1 Hour
20 ppm (23 mg/m3)
35 ppm (40 mg/m3)
8 Hour (Lake
Tahoe)
6 ppm (7 mg/m3)
---
Annual
Arithmetic
Mean
---
0.053 ppm(100
µg/m3)
1 Hour
0.25 ppm (470 µg/m3)
---
30 Day
Average
1.5 µg/m3
---
---
Calendar
Quarter
---
1.5 µg/m3
Same as Primary
Standard
Annual
Arithmetic
Mean
---
0.030 ppm (80
µg/m3)
---
24 Hour
0.04 ppm (105 µg/m3)
0.14 ppm (365
µg/m3)
---
3 Hour
---
---
0.5 ppm
(1300 g/m3)
1 Hour
0.25 ppm (655 µg/m3)
---
---
3
None
Same as Primary
Standard
Table Source: California Air Resources Board, 1999
ppm=parts per million
mg/m3=milligrams per cubic meter
µg/m3=micrograms per cubic meter
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Description of the Affected Environment
3.5.1
CALIFORNIA
State of California Registration Program: The Statewide Registration Program establishes a uniform
program to regulate portable engine-driven equipment units. Once registered in the program, engines and
equipment units can operate throughout the State of California and are not required to obtain individual
permits from local air districts. Local air districts enforce permitting, registration, and regulations set by
CARB. The Statewide Portable Equipment Registration Program was adopted on March 27, 1997, by
CARB. Owners and operators of portable engines and portable equipment units that meet the definitions
and requirements of the program are eligible for registration. Portable engines include, but are not limited
to, internal combustion engines in cranes, power generators, pumps, and service rigs.
Table 9. State ambient air quality standards with no Federal counterpart.
Pollutant
Averaging Time
Sulfates
24 Hour
Hydrogen
Sulfide
1 Hour
California Standards
Concentration
25 µg/m3
Federal Standards
Primary
Secondary
0.03 ppm (42 µg/m3)
In sufficient amount to produce an
extinction coefficient of 0.23 per
Visibility
kilometer—visibility of ten miles or
8 Hour (10 AM to
Reducing
more (0.07—30 miles or more for
6 PM, PST)
Particulates
Lake Tahoe) due to particles when
the relative humidity is less than
70 percent.
NO
FEDERAL
STANDARDS
Table Source: California Air Resources Board, 1999
ppm=parts per million
mg/m3=milligrams per cubic meter
µg/m3=micrograms per cubic meter
California/Mojave Desert Region Major Impacts Discussion Elements
Since a major portion of the proposed exercise would take place in the Mojave Desert region, it is
necessary to implement guidelines provided by the regulatory agencies. Under the California
Environmental Quality Act (CEQA), the Mojave Desert Air Quality Management District (MDAQMD) is
the expert commenting agency on air quality and related matters within the Mojave Desert jurisdiction or
impacting on the jurisdiction.
The MDAQMD has jurisdiction over the desert portion of San Bernardino County and the far eastern end
of Riverside County. This region includes the incorporated communities of Adelanto, Apple Valley,
Barstow, Blythe, Hesperia, Needles, Twentynine Palms, Victorville, and Yucca Valley. This region also
includes the National Training Center at Fort Irwin, the Marine Corps Air Ground Combat Center, the
Marine Corps Logistics Base, the eastern portion of Edwards Air Force Base, and a portion of the China
Lake Naval Air Weapons Station.
Direct Impacts
Direct impacts are the result of the project itself (from its construction and operation), in the form of project
activity and trips generated by the project. Examples of direct impacts are construction emissions
(equipment exhaust, wind erosion, vehicle exhaust), housing use activity (natural gas consumption) vehicle
travel-related emissions (vehicle exhaust, tire wear), material handling emissions (drilling, blasting,
transfers, crushing, screening, bagging), operational emissions (wind erosion, vehicle travel, vehicle
exhaust, tire wear), and employee/customer/delivery travel emissions (vehicle exhaust, tire wear).
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Description of the Affected Environment
Indirect Impacts
Indirect impacts are the result of changes that would not occur without the project. Examples of indirect
impacts on the surrounding community are numerous: construction of roadways (or roadway
modifications) and other infrastructure, construction and operation of new commercial/retail
establishments, changes in traffic/circulation patterns that result in increased congestion/delays, etc.
Significance Thresholds
A project is significant if it:
1.
2.
3.
4.
Generates total emissions (direct and indirect) exceed the thresholds given in Table 11; and/or,
Generates a violation of any ambient air quality standard when added to the local background; and/or,
Does not conform with the applicable attainment or maintenance plan(s); and/or,
Exposes sensitive receptors to substantial pollutant concentrations, including those resulting in a
cancer risk greater than or equal to 1 in a million and/or a Hazard Index (HI) (non-cancerous) greater
than or equal to 0.1.
These significance thresholds are not applicable to all projects. Contact the District to clarify whether your
project should be evaluated under these thresholds. In general, the emissions comparison (criteria number
1) is sufficient.
A significant project must incorporate mitigation sufficient to reduce its impact to a level that is not
significant. A project that cannot be mitigated to a level that is not significant must incorporate all feasible
mitigation. Note that the emission thresholds are given as a daily value and an annual value, so that multiphased project (such as project with a construction phase and a separate operational phase) with phases
shorter than one year can be compared to the daily value.
Table 10. Significant Emissions Thresholds
Criteria Pollutant
Annual Threshold
(tons)
100
25
25
25
15
Carbon Monoxide (CO)
Oxides of Nitrogen (NOx)
Volatile Organic Compounds (VOC)
Oxides of Sulfur (SOx)
Particulate Matter (PM10)
3.5.2
Daily Threshold
(pounds)
548
137
137
137
82
ARIZONA
The Arizona portion of the proposed exercise route would be located in areas of Yuma and La Paz Counties
that are in attainment for all criteria pollutants except for a section of the YPG in Yuma County that
exceeds the PM10 NAAQS.
The Arizona Department of Environmental Quality (ADEQ) requires “reasonable precautions to limit
excessive amounts of particulate matter from becoming airborne” (ADEQ 2001b). Reasonable measures
include but are not limited to dust suppressants, adhesive soil stabilizer, and wetting. This requirement
applies to construction related activities.
ADEQ Rule R18-2-324 requires portable sources to obtain a permit. The permit must be secured by the
owner. The state can issue a permit for state-wide operation or a county with an established air pollution
control program can issue a permit for operation within that county only.
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Description of the Affected Environment
3.6
NOISE
The background noise environment in the project area is highly variable. Human-made sources of noise
include railroads, roadway traffic on interstates and highways, industrial and farm operations, and
recreational activity, as well as military test and training activities (on MCAGCC and YPG), and
commercial, and military aircraft traffic. A detailed discussion of noise conditions resulting from military
aircraft flights in the project area can be found in the Yuma Test Range Complex EIS (USMC 1997).
3.7
BIOLOGICAL RESOURCES
The following section provides an overview of the biological resources found within the project area. The
Biological Evaluation prepared for this project (Charis Corporation 2002) includes a detailed discussion of
threatened and endangered species found in the project area.
The Biological Evaluation addresses potential impacts to Federally listed threatened and endangered
species, and State of California listed threatened and endangered species as well as species with special
designations under that State’s laws. Under the provisions of the Federal Endangered Species Act (ESA) of
1973 as amended (16 U.S.C § 1531 et seq.) Federal agencies are to ensure that actions they authorize, fund
or carry out are not likely to further jeopardize the existence of an endangered species (or species proposed
for listing) nor adversely modify it's critical habitat.
The California Endangered Species Act (CESA) (California Fish & Game Code §§ 2050, et seq.) generally
parallels the main provisions of the Federal Endangered Species Act, however, is limited in scope to those
species or subspecies native to California and also extends to those species that are proposed for listing.
The State of Arizona does not have a State endangered species protection act.
There are several Federal and California listed threatened or endangered species that are known to occur in
or near the project area and in the Lower Colorado River. As such, the Biological Evaluation was prepared
to assess potential impacts and identify methods to eliminate or minimize any threat to these species that
may be caused by the project. A summary of the contents of the Biological Evaluation is contained below.
As the proposed exercise route covers a distance of some 250 + miles and is linear in nature, general
information is provided on a regional basis with focus on only those areas deemed biologically sensitive.
Site specific field surveys were performed at each proposed use area during the months of February and
May 2001 and in January 2002 to determine existing site conditions, vegetation, and the potential for
encountering State of California and Federally listed threatened and endangered (T&E) species as well as to
observe and inventory general biological conditions and observe any impacts that may have been
noticeable from the Desert Scimitar 2001.
3.7.1
REGIONAL DESCRIPTION
The Lower Colorado River Basin is made up of river bottoms and terraces approximately 29 miles in length
and ranging in width up to 15 miles. Prior to the late 1800’s and subsequent river channelization,
impoundment, and arroyo cutting, the alluvial plains of the river bottom were wetter and less well-drained
than at present (Minckley and Brown 1982). Native riparian vegetation along the river included a
subtropical deciduous woodland of mesquites (Prosopis spp.), willows (especially Salix gooddingii), and
cottonwoods (Populus fremontii). Scrub and marsh vegetation included arrow weed (Pluchea sericea),
quailbush (Atriplex lentiformis), Baccharis spp. and tules (Scirpus spp). Most of the forests have been
reduced to isolated, scattered groves or have been replaced by the exotic tamarisk (Tamarix spp) and scrub
vegetation. Rainfall amounts are minimal, approximately 3.7 inches per year, and typically restricted to
winter months. Areas may periodically receive scattered heavy rainfall during summer thunderstorms.
Summer temperatures frequently exceed 100 degrees F. Due to low elevations, temperatures are extreme.
Outside of the river basin, the habitat is represented by southwestern basin and range topography,
characterized by numerous, generally north-south oriented mountain ranges alternating with valleys and
alluvial plains. Desert pavement is variously common, and is often well-developed and present in broad
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Description of the Affected Environment
patches. Soils generally range from loose-sandy to coarse-sandy loams on the bajadas and valley floors to
cobbles, boulder outcrops and talus on the mountain slopes. Rainfall can vary from one to five inches per
year. Areas may periodically receive scattered heavy rainfall during summer thunderstorms. Summer
temperatures frequently exceed 100 degrees F. Night frosts are common in winter months.
Regional vegetation is Sonoran creosote bush scrub (after Holland 1986) and Sonoran wash woodland. The
scrub community is generally dominated by burro bush (Ambrosia dumosa) and creosote bush (Larrea
tridentata); big galleta grass (Pleuraphis rigida) is common in areas with the loosest sand and in small
runnels. Species richness and plant density are generally low to moderate (approximately 5-15 % cover).
The area’s hydrology patterns dictate the extent and nature of the woodland. Several-yard-wide, sandy to
cobbly drainages that carry periodic runoff to a regional drainage, resulting in “gallery” washes. These
drainages are often incised, from a half to several yards, and densely vegetated along the banks by both
shrubs and trees. Common shrubs include brittlebush (Encelia farinosa), cheesebush (Hymenoclea salsola),
and desert lavendar (Hyptis emoryi). Associated trees are aphyllous or microphyllous with a high
proportion of chlorophyll in or beneath the bark or stems (Turner and Brown 1982), primarily including
ironwood (Olneya tesota) and palo verde (Cercidium floridum) and smoke tree (Psorothamnus spinosus);
honey mesquite (Prosopis glandulosa) is occasional.
Sheet-flow areas are actually contiguous gallery washes. As such, they are characterized by scattered trees
and shrubs and generally a gravelly substrate with coarse-sandy soils. Such areas are found in western
Chuckwalla Valley where the intense water flows off the Chuckwalla Mountains prompted the construction
of earthen dikes, several decades ago, to protect Interstate 10.
Smaller channels, or runnels, form a network of shallow drainages that often fail to either flow or provide
through-flow to larger drainages. They are typically only a yard or less wide, one-to-few inches deep, and
irregularly vegetated by locally common shrub species, especially brittlebush and big galleta grass. Where
the greater runoff from desert pavement flows into these runnels, arboreal elements from the larger washes,
albeit stunted, are also present.
The proposed routes and support activities would occur within several subdivisions of two desert floristic
provinces: the Sonoran and Mojave. Two communities, the Mojave Desert Scrub and Sonoran Desert Scrub
communities are dominant throughout the project area and may mix and overlap in many areas. The
following is a summary discussion of pertinent vegetative communities within the project area
characterized per the Holland Classification System (Holland 1986).
Sonoran Desert Scrub (SDS). This community is composed of two distinct sub-types; Sonoran Creosote
Bush Scrub (SCBS) and Sonoran Desert Mixed Scrub (SDMS). SCBS is characterized by the presence of
creosote bush growing on well-drained soils on slopes, fans, and in valleys. Growing season is from winter
to early spring. Annuals flower in late February to March, given sufficient rainfall. SCBS is the dominant
plant community below 3000 ft throughout the Colorado Desert subdivision of the Sonoran Desert. SDMS
includes members of the Cactaceae and Agavaceae in community composition. This sub-community is
generally found above 1000 ft on rocky well-drained slopes. With typically higher biodiversity, wildlife
apparently find the higher floristic and structural diversity offered by an SDMS area more inviting than
adjacent communities.
Mojave Desert Scrub (MDS). In California, Mojave Desert Scrub can be found from Death Valley to the
Little San Bernardino Mountains. MDS is typically associated with well-drained non-alkaline soils on both
desert flats and slopes generally below 4,000 ft. Dominant species associated with MDS are creosote bush
and burro bush (Ambrosia dumosa). Other common species include cheesebush (Hymenoclea salsola),
desert trumpet (Eriogonum inflatum), red brome (Bromus madritensis v rubens), desert dandelion
(Malacothrix glabrata), fiddelneck (Amsinckia sp), spiny herb (Chorizanthe rigida), globe mallow
(Sphaeralcea ambigua), and cat’s claw (Acacia greggii). Common cactus species are beavertail cactus
(Opuntia basilaris), pencil cholla (O. ramosissima), and golden cholla (O. echinocarpa). While similar in
appearance to Sonoran Desert Scrub, lower winter temperatures provide for later growth and flowering. As
in Sonoran Desert Scrub, there are two distinct winter and summer floras. There are two sub-types of MDS:
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Mojave Mixed Scrub and Steppe (MMSS), associated with shallow granitic or sandy soils on slopes
between 200 ft and 5000 ft, and Mojave Wash Scrub (MWS). At lower elevations, creosote is a common
component. In higher elevations, saltbush, buckwheat (Eriogonum sp), burrobush, and Mormon tea
(Ephedra sp) are common.
Developed (Agricultural and Urban). Much of the proposed exercise is to be conducted within developed
areas of the Palo Verde Valley and within the urban influence of the towns of Blythe and Desert Center.
Urban and agricultural environments can include a mix of native and imported species as well as a mix of
structural forms sometimes used by wildlife. Irrigation canals and ditches provide a place for riparian
vegetation to thrive year-round throughout the developed agricultural area and provide cover and feeding
opportunities for many types of wildlife.
Desert Chenopod Scrub (DCS). This community is identified by the low growing small-leaved
(microphyllous) shrubs (typically halophytic or xerophytic Atriplex sp) growing near or within playa
margins. This community is often associated with poorly drained alkaline soils found at lower elevations in
valley bottoms in both the Mojave and Sonoran Deserts. Dominant species associated with this community
are four-winged saltbush (Atriplex canescens), shadscale (A. confertifolia), desert holly (A. hymenelytra),
and cheesebush.
Desert Dry Wash Woodland (DDWW). This community consists of drought tolerant, small-leaved,
deciduous trees found in washes, drainages, and riparian areas. Many of the tree species in this community
are in the Fabaceae. Typical genera include Prosopis and Olneya. Trees can reach 10 meters but typically
do not exceed 5 meters. Local growth assemblages may occur as either dense woodland in a more open and
dispersed pattern. This community can be found in the sand or gravel soils of washes under 2500 ft
throughout the Mojave and Colorado Desert subdivision of the Sonoran Desert.
Desert Washes (DW). Many desert plant communities are characterized by a landscape of braided washes
focusing water into playas, dunes, or rivers. Washes vary widely in breadth and depth. At their sources,
there may little to differentiate a wash community from adjacent communities. In some cases, higher
moisture availability allows specimens to develop a relatively robust stature and lush foliage dependent on
the amount and frequency of inundation. If present, these enhancements serve to promote high biodiversity.
This community typically occurs below 5000 ft as sandy arroyos, washes, and subirrigated bajadas.
Dominant species in this community are cat claw, desert willow (Chilopsis linearis), Mormon tea, and
indigo bush (Psorothamnus arborescens).
3.7.2
SPECIAL STATUS SPECIES
Plant Species
Table 12 lists Federally and State of California listed and special status species which may be found within
the project area.
Wildlife Species
Species listed by State and Federal agencies as Endangered or Threatened and which may be encountered
during the exercise are listed in Table 11.
Several other animal species may be present in the project area that are not Federally or State of California
listed T&E species, however may sustain impacts due to the action, they are:
Sonoran Population of Desert Tortoise
Although the Mojave population of the desert tortoise (Gopherus agassizii ) was listed as threatened under
the ESA in 1990, the USFWS subsequently ruled that listing of the Sonoran population (south and east of
the Colorado River) was not warranted (AIDTT 2000). Nevertheless, land management agencies, Arizona
Game and Fish Department (AGFD), and the USFWS have recognized the need to continue to monitor the
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Description of the Affected Environment
status of the Sonoran population and to take action if necessary to provide additional conservation. Major
threats to this population include disease, predation by feral dogs, extended drought, urban and agricultural
development, roads, off-highway vehicle activity, mining, and grazing by livestock and wild horses and
burros.
Table 11. T&E and sensitive plant species that may occur within the project area.
Scientific Name
Acleisanthes longiflora
Common Name
Angel trumpet
Status
CNPS 2
Community
SDS
Astragalus insularis v harwoodii
Harwood’s rattleweed
CNPS 2
SDS
A. lentiginosus v coachellae
Coachella Valley milkvetch
FED E
CNPS 1B
SDS
Carnegiea gigantea
Saguaro
CNPS 2
SDMS
Castela emoryi
Crucifixion thorn
CNPS 2
SDS/MDS
Colubrina californica
Snakebush
CNPS 2
SCBS
Cryptantha costata
Ribbed Cryptantha
CNPS 4
SDS/MDS
Cryptantha inequata (holoptera)
Winged Cryptantha
CNPS 4
SDS/MDS
Ditaxis clariana
Glandular ditaxis
CNPS 2
SCBS
CNPS = California Native Plant Society Designations
1A -Plants presumed Extinct in CA
1B - Plants rare, threatened or endangered in CA and elsewhere
2 - Plants rare, threatened or endangered in CA but more common elsewhere
4 – Plants of limited distribution (significant locally)
FED E – Federally Endangered
SDS – Sonoran Desert Scrub
SDMS – Sonoran Desert Mixed Scrub
SCBS – Sonoran Creosote Bush Scrub
MDS – Mojave Desert Scrub
A map showing the distribution of the Sonoran population of desert tortoise, based on records in the AGFD
Heritage Data Management System, indicates past occurrence of desert tortoise within the project area,
specifically the YPG and Quartzsite-Cibola Staging Areas (Yuma and La Paz Counties, Arizona) (AIDTT
2000). However, the Ehrenberg Wash route may pass through public lands categorized as desert tortoise
habitat by BLM.
Table 12. Threatened and endangered wildlife potentially occurring in the project area.
Wildlife
Status
Scientific Name
Xyrauchen texanus
Common Name
Razorback Sucker
Federal
E
CA State
E
Gila elegans
Bonytail Chub
(Believed to extirpated below Lake
Havasu)
E
E
Gopherus agassizii
Desert Tortoise
T
T
Rallus longirostris yumanensis
Yuma Clapper Rail
E
T
Empidonax traillii extimus
Southwestern Willow Flycatcher
E
N/A
Haliaeetus leucocephalus
Bald Eagle
FPD
E
Pelecanus occidentalis californicus
California Brown Pelican
E
E
Charadrius montanus
Mountain Plover
FPT
N/A
Falco peregrinus anatum
American Peregrine Falcon
N/A
E
Laterallus jamaicensis coturniculus
California Black Rail
N/A
T
Melanerpes uropygialis
Gila Woodpecker
N/A
E
Colaptes chrysoides
Gilded Northern Flicker
N/A
E
Coccyzus americanus occidentalis
Western Yellow-billed Cuckoo
N/A
E
E – Listed Endangered, T – Listed Threatened, FPD – Federally Proposed (Delisting), FPT – Federally Proposed (Threatened)
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
Although the northwestern and eastern arms of YPG are considered potential desert tortoise habitat, only
one tortoise carapace has been observed over the past five years by the installation biologist. Potential
negative impacts to desert tortoise populations on YPG are considered low.
Wild Horses and Burros
The Bureau of Land Management (BLM) is responsible for managing wild horses (Equus caballas) and
burros (Equus asinus) on the public rangelands in accordance with the Wild Horse and Burro Act of 1971.
The BLM Yuma Field Office is responsible for managing herds within the Cibola Herd Management Area
(CHMA), which spreads across the border of Arizona and California, and is located primarily west of US
95 in Arizona, east of Highway 78 in California, north of I-8 and south of I-10 (BLM CHMA website:
www.az.blm.gov/whb/cibolahma.htm, 2001b). This area includes BLM, YPG, BOR managed lands
proposed for use in this exercise.
According to the BLM CHMA website, the current population of burros in the CHMA is about 300. During
the summer months, the burros are concentrated along the Colorado River, or other permanent water
source. In late fall or early winter, depending upon rainfall, they disperse throughout the HMA. They begin
their movement back to the river about May or June as the temperatures rise and the mesquite beans
mature. The wild horses remain near a permanent water source year round. There are approximately 130
wild horses in the HMA. The BLM manages wild horse and burro populations within the CHMA in
accordance with other resource needs, and periodically removing excess animals.
Desert Bighorn Sheep
Desert bighorn sheep, also called Nelson’s bighorn sheep (Ovis canadensis nelsoni) occur in California in
desert mountain ranges from the White Mountains of Mono and Inyo counties, south to the San Bernardino
Mountains, and southeastward to the Mexican border (California Department of Fish and Game website
www.dfg.ca.gov/whdab/cwhr/M183.html, 2002). Desert bighorn sheep occur in desert mountain ranges in
the southern, northern and western sections of Arizona (Arizona Game and Fish website
www.gf.state.az.us/frames/fishwild/bshp_map.htm, 2002). Desert bighorn sheep populations are estimated
at approximately 20,000; of which approximately 4,500 are found in Arizona (Arizona Game and Fish
website www.gf.state.az.us/frames/fishwild/htnsheep.htm, 2002)
Desert bighorn sheep use rocky, steep terrain for escape and bedding. They remain near rugged terrain
while feeding in open habitats including meadows and low, sparse brushlands on a wide variety of plant
species. They prefer open areas that are close to steep, rugged terrain for escape, lambing, bedding, water
sources and travel routes. Critical water sources include springs, water in depressions, and human-made
sources. Desert bighorn sheep are active yearlong, mostly in the daytime except during hot midday. Rutting
may occur yearlong for desert bighorn sheep. Births may occur at anytime but most occur from January to
April. Lambing season is from mid-April to early June. (California Department of Fish and Game website
www.dfg.ca.gov/whdab/cwhr/M183.html, 2002)
3.7.3
INDIVIDUAL SITE ASSESSMENTS OF POTENTIALLY SENSITIVE AREAS
Arizona
Roadrunner Assembly Area
Existing Condition and Use. Highly disturbed area with compacted soils. Used for a visitor area for
camping primarily during the winter months.
Vegetation Cover. Vegetative cover is sparse. Consistent with description for Sonoran Desert Scrub.
Composition: Aspect-dominant vegetation, which is largely confined to the troughs (drainages) includes
palo verde, ironwood, creosote bush, brittlebush, burro bush, and rattany (Krameria grayi).
T&E Species. None observed. Slight potential for desert tortoise (not listed in this part of AZ).
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
BOR Stockpile Site 105, Cibola Road
Existing Condition and Use. Highly disturbed compacted soils. Functions as material stockpile for Bureau
of Reclamation.
Vegetation Cover. Denuded within activity area, sparse vegetation at margins. Composition is consistent
with description for Sonoran Desert Mixed Scrub. The surrounding native habitat is a relatively lush
alluvial plain, dominated by palo verde, ironwood, creosote bush, brittlebush, burro bush, allscale (Atriplex
polycarpa), and boxthorn (Lycium cooperi).
T&E Species. Plants - Observed saguaro (Carnegiea gigantea) in the vicinity; however, it was well off the
designated traffic corridor. Wildlife - None observed. Medium potential for desert tortoise due to high
quality habitat surrounding the stockpile area (tortoise not listed in this part of AZ).
BOR Stockpile Site 98, River Crossing
Existing Condition and Use. Highly disturbed and compacted soils. Functions as a material stockpile for
Bureau of Reclamation. Bounds Cibola National Wildlife Refuge and is separated by a fence and large
piles of riprap and other rock materials.
Vegetation Cover. Denuded in activity area, moderate to heavy at margins. Composition is chiefly
tamarisk (Tamarix parviflora) and quail bush (Atriplex lentiformis). Site is on the margin of remnant desert
riparian community. Area immediately to the north is farmland under cultivation.
T&E Species. Plants - None observed. Wildlife - None observed minimal potential for southwestern
willow flycatcher and Yuma clapper rail.
Colorado River Crossing – Arizona Side
Existing Condition and Use. Disturbed embankments that lead to the edge of the Lower Colorado River.
Adjacent to a small backwater (BOR dredge slip) commonly referred to as “Hippy Hole” which receives a
high incidence of seasonal recreational use including camping, boat launching and vehicle use on the beach
and in the vegetated areas. Area is primarily sand and highly disturbed. Large quantities of trash and other
items that have been discarded litter the area. Habitat in general is in poor condition due to use and
proximity to roads and camping areas.
Vegetation Cover. Moderate to dense within proposed river ingress corridor. Composition is chiefly
tamarisk and quail bush. Vegetation is in poor condition due to trampling, visitor use and misuse. Only
remnants remain of native desert riparian community due to tamarisk infestation.
T&E Species. Plants - None observed. Wildlife - No listed wildlife or sign observed. Potential for breeding
and/or nesting Yuma clapper rail in rushes on the north end of the lagoon area, razorback sucker in the
lagoon area. Likelihood of either Yuma clapper rail or razorback sucker to be present is low due to
degraded habitat and high impact use of the area by the public; however, nesting Yuma Clapper Rail has
been observed to the south of the lagoon area in the Cibola NWR and to the north of the site on the
California side of the river. Juvenile razorback suckers are known to utilize calm backwater areas similar to
the “Hippy Hole” lagoon however the likelihood of encountering razorback sucker in the Cibola stretch of
the Colorado River is very minimal. (Note: the BLM Yuma Field Office Biologist has reported that
Arizona Game and Fish has released razorback sucker hatchery stock into the “A-7 Backwater” and that
individuals may be present in the Cibola area).
California
Colorado River Crossing – California Side
Existing Condition and Use. Disturbed. Includes a man-made soil levee with rock revetment. Heavily
used as access road for recreational purposes, primarily camping. Compacted soils.
Vegetation Cover. On side banks, moderate to dense. Composition is primarily arrow weed (Pulchea
sericea) at road margins intermixed with tamarisk on both bank sides. Isolated stands of screw bean
mesquite (Prosopis glandulosa) were observed but are well out of the proposed egress corridor and
construction area.
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
T&E Species. Plants - None observed. Wildlife - No listed wildlife or sign observed. Likelihood of
southwestern willow flycatcher presence is low due to high impact use of the area by the public and the
very poor quality of habitat for nesting.
Palo Verde County Park
Existing Condition and Use. Disturbed. Functions as a county park and boat launch facility. Soils are
compacted. Area is denuded.
Vegetation Cover. Developed. Cover is relegated to park margin near water edge. Park area is otherwise
open space. Composition is primarily tamarisk planted for wind and sun protection and non-native trees.
T&E Species. Plants - None observed. Wildlife - No listed wildlife or sign observed. Slight potential for
southwestern willow flycatcher in adjacent irrigation canals, slight potential for Yuma clapper rail in rushes
within sight of park area, slight potential for razorback sucker in the backwater by the boat launch facility.
Likelihood of presence of these species is low due to high impact use of the area by the public. Rushes
surrounding the backwater at Oxbow backwater within the vicinity of the park have been observed to be
used by Yuma clapper rail as breeding and/or nesting areas.
Palo Verde Engagement Area
Existing Condition and Use. Area is highly disturbed by extensive agricultural use. Area is interwoven
with irrigation ditches and compacted dirt roads.
Vegetation Cover. Irrigation canals and drainages are plentiful throughout the farmed area. However, most
are shallow, typically are bordered by roads and active agriculture, actively cleared of vegetation and offer
little to no wildlife habitat. A few offer moderate habitat for riparian birds as they are densely vegetated
with arrow weed, quailbush, and cattails (Typha sp.). Cover is agricultural fields mainly supporting row
crops.
T&E Species. Plants - None observed or likely to be present. Wildlife - No listed wildlife or sign observed.
Potential for Southwestern Willow Flycatcher in vegetated irrigation ditches.
Wiley Well / Milpitas Wash Road
Existing Condition and Use. Disturbed. Soils are compacted. Wiley Well / Milpitas Wash Road is a
regularly maintained/graded road with heavy use from private and Border Patrol vehicles.
Vegetation Cover. No vegetation on road or within road burms, however vegetation on either side of road
is consistent with description for Sonoran Desert Scrub. Composition: Aspect-dominant vegetation, which
is largely confined to the troughs (drainages) includes palo verde, ironwood, creosote bush, brittlebush,
burro bush, and rattany (Krameria grayi).
T&E Species. Plants – None observed or likely to be present. Wildlife – High likelihood for desert tortoise
to be encountered due to high quality habitat on either side of the road.
Blythe Airport
Existing Condition and Use. Site is an abandoned World War II air base with remnant concrete runways.
Highly disturbed by airfield construction and former and recurrent uses.
Vegetation Cover. Developed. Adjacent areas have been rigorously used for agriculture but have since
been abandoned. Cover is sparse, although vegetation is recovering. Very few patches of remnant native
creosote bush scrub habitat less than 1/8 acre in size. Composition is primarily creosote bush and
cheesebush. Consistent with description of Sonoran Desert Scrub.
T&E Species. Plants - None observed and none anticipated to occur. Wildlife - No listed wildlife or sign
observed. Extremely minimal likelihood of encounter with desert tortoise due to lack of habitat and
disturbances.
Midland LTVA
Existing Condition and Use. Highly disturbed by heavy frequent public use as a Long Term Visitor Area.
Recreational vehicles were observed parked throughout the area. Soils are compacted. Broad areas of desert
pavement are present.
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
Vegetation Cover. Disturbed. Most vegetation has been denuded. Virtually no cover within the area
proposed for use. Vegetation exists primarily only in ravines or ditches where vehicles cannot easily be
driven. Composition is Sonoran creosote bush scrub/woodland habitat intersected by shallow washes. The
latter are largely vegetated by scrub elements with scattered, small trees. No vegetation within proposed
command post site.
T&E Species. Plants - None observed. Wildlife - No listed wildlife or sign observed. Minimal likelihood of
encounter with desert tortoise due to extremely disturbed nature of the habitat and size of the LTVA, which
covers several hundred acres the majority of which is disturbed. A 1996 survey for desert tortoise at the
LTVA by a BLM biologist found no active tortoise sign but indicated that tortoises had been present in the
area in the past (Midland Long Term Visitor Area Management Plan and Environmental Assessment,
BLM, Oct 24, 1996).
Area Near Midland Town Site
Existing Condition and Use. Highly disturbed, currently by frequent public use and previously by UG
Gypsum. Similar in appearance to the Midland LTVA although immediate area under consideration is
smaller in overall surface area. Areas of desert pavement are present, soils are compacted and remnant
buildings and foundations are scattered throughout area.
Vegetation Cover. Denuded in area proposed for use in exercise. Composition is Sonoran creosote bush
scrub/woodland habitat intersected by shallow washes. The latter are largely vegetated by scrub elements
with scattered, small trees. No vegetation within proposed command post site.
T&E Species. Plants - None observed. Wildlife- No listed wildlife or sign observed. Surrounding area is
low to medium quality desert tortoise habitat due to proximity to the disturbed area. No sign or animals
were observed.
Landfill
Existing Condition and Use. Highly disturbed by operations and personnel of the Riverside County
Landfill. Soils are compacted in areas and excavated and stockpiled in others.
Vegetation Cover. Denuded in area proposed for use in exercise. Composition of surrounding vegetation
is Sonoran creosote bush scrub/woodland habitat intersected by shallow washes. The latter are largely
vegetated by scrub elements with scattered, small trees. No vegetation within proposed command post site.
T&E Species. Plants - None observed. Wildlife- No listed wildlife or sign observed. Surrounding area is
low to medium quality desert tortoise habitat due to proximity to the disturbed area. No sign or animals
were observed
Midland Engagement Area
Existing Condition and Use. Moderate to highly disturbed. Area in general reflects high level of current
and previous use. However, many roads within the proposed engagement area may not be suitable for use
due to recovering vegetation in the roadway and increased risk of take.
Vegetation Cover. Consistent with description of Sonoran Creosote Bush Scrub with Desert Dry Wash
Woodland. Cover is sparse in most open areas, heavier in washes. Composition is primarily creosote in
open areas, with tamarisk dominant in the washes.
T&E Species. Plants - Foxtail cactus (Coryphantha alversonii) observed within three meters of a proposed
engagement route east of the Midland Road. Cryptantha costata and Asceisanthes longiflora may be
encountered in the vicinity of Midland Road, however none were observed. Wildlife - Tortoise sign
(carcass) was observed along a route near the west boundary of the engagement area. Age of carcass was
estimated to have been dead between 4 –5 years and no other sign was observed. Habitat for tortoise is low
to medium quality.
Chuckwalla Road
Existing Condition and Use. Disturbed. Proposed sites consist of the wide areas afforded by Interstate
exit/entrance ramps south of and immediately adjacent to I-10. Typically used as unofficial rest areas with a
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
considerable amount of trash and evidence of heavy use by the public. Also used as stockpile sites for road
materials.
Vegetation Cover. Consistent with description of Sonoran Desert Scrub. Cover is sparse to denuded within
the area proposed. Composition is predominately creosote bush. Observed a few individual specimens of
ironwood.
T&E Species. Plants - None observed. Wildlife - No listed wildlife or sign observed. Extremely minimal
likelihood of encounter with desert tortoise due to proximity to I-10 and high level of disturbance in area.
Desert Center Airport
Existing Condition and Use. Disturbed, used as private airport. Ground consists of concrete pads and a
paved runway. Area is accessible by an improved dirt road. Currently appears infrequently used.
Vegetation Cover. Developed - adjacent areas have been disturbed but are recovering. Denuded in
proposed assembly area. Sparse along margins and in area proposed for bivouac. Approximately five acres
are proposed for use oin this exercise area. Composition: Predominately cheesebush at margins.
T&E Species. Plants - None observed. Only slight possibility of encounter with Coachella Valley milkvetch (A. lentiginosus v Coachellae) in sandy disturbed areas surrounding the runway and paved areas.
Wildlife - No listed wildlife or sign observed and none expected to be present.
Palen Pass Road
Existing Condition and Use. Disturbed. Road is periodically graded. Soils are compacted.
Vegetation Cover. Road is denuded. Vegetation surrounding road is consistent with description of Sonoran
Creosote Bush Scrub with Desert Dry Wash Woodland. Cover is moderate in most open areas, heavier in
washes. Some areas adjacent to road have been disturbed, tracks from off-highway vehicle use were
observed.
T&E Species. Plants – None observed. Wildlife - no listed wildlife or sign observed. Minimal likelihood of
encounter with desert tortoise due to habitat quality however tortoises are known to occur in the area.
Cal Trans Stockpile Site (Postmile 10)
Existing Condition and Use. Disturbed. Used as a material stockpile site for California Department of
Transportation (Cal Trans). The native habitat surrounding both sites is loose- to soft-sandy,
Vegetation Cover. Denuded in proposed command post area. Composition is allscale-creosote bush scrub
with common cheesebush (Hymenoclea salsola) and scattered ironwood and palo verde. Moderately dense
stand of mesquite on southwest margin. No vegetation within proposed use area.
T&E Species. Plants - Individual specimens of Coachella Valley milk-vetch have been documented along
California Highway 177 between Desert Center and the stockpile. Specimens may exist on disturbed fringe
area of stockpile yard. Wildlife- No listed wildlife or sign observed, nor expected to be present.
Granite Pass
Existing Condition and Use. Highly disturbed. Appears to be used as an illegal dumping site and rest stop.
Soils highly compacted.
Vegetation Cover. Consistent with description of Mojave Desert Scrub community. Denuded to sparse.
Composition is highly dissected, moderately sparsely-vegetated bajada. Chiefly creosote bush.
T&E Species. Plants - None observed. Wildlife - No listed wildlife or sign observed. Extremely minimal
likelihood of encounter with desert tortoise due to extreme disturbance of area. Chance of encounter of
desert tortoise on the south side of Highway 62 is high due to active tortoise sign observations in 2001 and
2002. As such, the south side of Highway 62 in this area would be off-limits to Desert Scimitar 02.
Iron Mountain Pumping Station and Rice, MWD
Existing Condition and Use. Highly disturbed. Compacted soils and paved areas. Exercise areas to be
used at Iron Mountain include capped landfill, a portion of a paved road used for asphalt production and a
paved airstrip. Exercise area to be used at Rice is excavated and stockpiled soil.
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
Vegetation Cover. Denuded in proposed area. Vegetation surrounding the exercise sites is consistent with
the description of Sonoran Creosote Bush Scrub with Desert Dry Wash Woodland. No vegetation within
proposed use area.
T&E Species. Plants – None observed. Wildlife – No listed wildlife observed. Minimal likelihood of
encounter with desert tortoise due to high level of use and disturbance of area.
3.7.4
INVASIVE NON-NATIVE PLANTS
Executive Order 13112 mandates that each Federal agency whose actions may affect the status of invasive
species shall take reasonable actions to prevent the introduction of invasive species, and not allow actions
that could promote, introduce, or spread invasive non-native plants. Non-native plants are becoming
increasingly abundant in California and Arizona deserts. Populations of annual grasses, noxious weeds, and
tamarisk in washes are increasing. Invasive plant species compete with native species. Both native and nonnative flora are adapted to respond rapidly to rainfall and complete their life spans in a very short time.
Where non-natives are dominate, natives face severe competition for available water, germination areas,
and sunlight. Non-native plants observed at all sights consisted of primarily tamarisk. Due to the time of
year that the project area was observed few if any annual grasses or noxious weeds were observed.
3.8
CULTURAL RESOURCES
Due to the limited development in this desert region, the area along the proposed exercise route has been
subject to very limited survey effort. However, local residents speak of many unrecorded cultural sites and
all accounts support profound prehistoric and historic use of the wide area surrounding the Colorado River.
Archeological site density is predictably high in areas with a resource as important as water, and low in arid
environments.
The project area spans several ecozones, but can be divided into two general categories: the river and the
arid regions. The river now serves a modern population, which has practiced extensive mechanized
agricultural development on the same land that would have supported prehistoric populations. Despite
continued use and focused development of the river region through time, numerous cultural sites have
survived to offer a glimpse of the magnitude of meaning the region and resource had to past populations.
For the project areas close to the river, cultural resource surveys (most often for utility companies) have
resulted in the recording of a variety of site types that indicate prolonged, continuous use of the area for at
least 5,000 years (Purcell et al 2000). In the arid regions away from the river, both prehistoric and historic
sites tend to cluster near wells, natural water tanks (tinajas) and natural springs. Most of these areas have no
recorded cultural sites within the surrounding one- mile.
3.9
PALEONTOLOGICAL RESOURCES
Several major geologic deposits within the California Desert Conservation Area are known to contain
paleontological resources (BLM 2001a). With the exception of Quaternary lacustrine strata, the majority of
the known highly sensitive areas and protected areas occur in areas of some relief where dissection has
exposed the fossilized remains. These areas as a whole are randomly dispersed throughout the CDCA.
Protection of paleontological resources in the CDCA is accomplished primarily through control of vehicle
routes (BLM 2001a) Paleontological resources were not specifically identified in the resource management
plans for the Arizona portion of the project area; however, petrified wood is known to occur on YPG
(USAYPG 1998).
3.10
VISUAL RESOURCES
The rugged desert landscape within the project area provides a range of scenic values, especially in the
wilderness areas. The BLM recognizes theses values as a definable resource and an important recreation
experience, and manages them accordingly (BLM 1987, BLM 2001a). Proposed activities are evaluated to
determine the extent of change created in any given landscape and to specify appropriate design or
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
mitigation measures using the BLM’s contrast rating process. Similarly, YPG manages the visual quality
on its land consistent with its primary military mission (USAYPG 1998).
3.11
RECREATION / VISITOR SERVICES
The California desert attracts millions of visitors annually to its wide spectrum of recreational opportunities
(BLM 2001a). Similarly, recreation is a major use of public lands on the Arizona portion of the project area
(BLM 1987, BLM 1994). The Lower Colorado River is the most important freshwater recreation area in
the Southwest, being within a half a day’s drive for more than 17 million people (BLM 2001a). Popular
water-based recreational activities in the area near the River include boating, fishing, water skiing, and
wildlife watching. There are two seasons of recreation use in the project area, warm season and cool season
(BLM 1994). During the warm season, visitors are drawn to the area by water-based activities, with peak
use on weekends and holidays. During the cool season, the primary use of the area is for long-term
camping, hiking, nature watching, and off-highway vehicle use.
A BLM map guide (1998) describes the Oxbow Recreation Site as being a “popular recreation site
providing a diversity of recreation opportunities. Fishing and wildlife viewing are popular year-round.
Summer season use is focused primarily on watersports such as power-boating and jet-skiing. Facilities
available at the Oxbow Recreation Site include a boat ramp, restrooms and trash containers. This site is
located adjacent to popular waterfowl hunting areas. The rugged landscape and availability of water make
this area ideal habitat for many types of wildlife….”
3.12
PUBLIC SERVICES AND UTILITIES
The project area includes several existing utility corridors for electrical power, oil and gas products, water,
and coaxial and fiber-optic cables (USMC 1997, BLM 2001a). Many of these corridors are along roads
used as part of the exercise route. Key corridors are along California Highway 78 between Palo Verde and
Rice, the Midland-Rice Road, I-10 between Blythe and Desert Center, and California Highway 177 near
Highway 62. The proposed Iron Mountain, Granite Pass, and Rice Assembly Areas are near to the
Colorado River Aqueduct. There are also several communication sites within the project area, including
radio and TV broadcasting, microwave, cellular, commercial mobile radio, and private mobile radio
facilities.
3.13
WASTES (HAZARDOUS/SOLID)
Hazardous materials are defined and regulated by several Federal and state environmental laws including
the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), Resource
Conservation and Recovery Act (RCRA), Toxic Substances Control Act (TSCA),and Clean Air Act
(CAA). The types of hazardous materials used during the proposed exercise are limited to fuels and other
petroleum, oil, and lubricants (POLs) used in the vehicles, watercraft, aircraft, and equipment. Primary
fuels used in the exercise would be JP-5, diesel, and gasoline.
3.14
SOCIOECONOMICS
The project area spans parts of two states and four counties: Yuma and La Paz Counties in Arizona, and
Imperial and Riverside, and San Bernardino Counties in California. Economic activity is centered around
the town of Blythe, CA, and the unincorporated communities of Quartzsite, Ehrenberg, and Cibola, AZ;
and Palo Verde, Ripley, and Desert Center, CA. Agriculture, tourism, and government services are major
economic activities in this area. Much of the tourist revenue is associated with recreational use of public
lands.
3.15
ENVIRONMENTAL JUSTICE AND PROTECTION OF CHILDREN
Title VI of the Civil Rights Act and Executive Order 12898 (Environmental Justice) requires that projects
be evaluated to determine whether minority and low-income households would experience greater impacts
relative to those experienced by other segments of the population. Similarly, Executive Order 13045
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Environmental Assessment – March 2002
US Bureau of Land Management
Description of the Affected Environment
(Protection of Children from Environmental Health Risks) requires that projects be evaluated to identify
and assess the environmental health risks and safety risks that may disproportionately affect children.
The proposed exercise route would take place on existing roadways and would not involve any
modification to existing communities or residential relocation. Most of the activity would take place on
military or public lands away from population centers.
Desert Scimitar 02 Exercise
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Environmental Assessment – March 2002
US Bureau of Land Management
Environmental Consequences and Mitigation
4.0
ENVIRONMENTAL CONSEQUENCES AND MITIGATION
This section briefly describes the environmental consequences resulting from implementation of the
Proposed Action, Reduced Route Alternative, Boat Launch Alterative, and No Action Alternative. Potential
impacts are compared against a set of significance criteria. Where there are impacts, one or more mitigation
measures are recommended.
4.1
CRITICAL ELEMENTS OF THE HUMAN ENVIRONMENT
A number of environmental regulations, statutes, and executive orders must be considered in the NEPA
process (USMC 1998). Table 11 summarizes potential impacts to various elements of the human
environment, including the critical elements: listed in BLM Manual H-1790-1, Appendix 5, as amended.
Elements for which there are not impacts would not be discussed further in this document.
Table 13. Summary of potential impacts on BLM critical elements.
Potential Impact
Proposed
Action
Reduced
Route
Alternative
Boat Launch
Alternative
No Action
Alternative
Section(s) of EA
Where Addressed
Air Quality
Yes
Yes
Yes
No
4.6
ACECs
No
No
No
No
4.2
Cultural Resources
No
No
No
No
4.9
Farmlands
No
No
No
No
4.2
Environmental Element
4.2
Invasive, Non-native Species
Yes
Yes
Yes
No
4.8
T&E Animal Species
Yes
Yes
Yes
No
4.8
T&E Plant Species
Yes
Yes
Yes
No
4.8
4.14
Wastes (hazardous/solid)
Yes
Yes
Yes
No
Water Quality (surface and ground)
Yes
Yes
Yes
No
4.4
Wild and Scenic Rivers
No
No
No
No
4.2
Wilderness
No
No
No
No
4.2
Environmental Justice
No
No
No
No
4.16
Visual Resource Mgmt.
No
No
No
No
4.11
GEOLOGY AND SOILS
Impacts to geology and soil resources are considered significant if one or more of the following criteria is
met: 1) geological resources are damaged or mineral resources depleted; 2) activities result in severe soil
erosion; 3) permanent contamination of soil occurs that would restrict future land use.
4.2.1
PROPOSED ACTION
Potential Impacts
Implementation of the Proposed Action would not deplete or damage geological resources within the
project area. The Proposed Action would involve vehicle travel on established, maintained roads within the
project area. The number of vehicles used in this exercise would not add significantly to the total vehicle
use of the area, although the intensity of use might be temporarily greater. Minor degradation of unpaved
roads could occur due to heavy vehicle traffic but it is unlikely that this would exceed the design
parameters for such roads. Vehicle and aircraft use could potentially cause minor amounts of soil loss by
wind erosion. Although this would be insignificant in terms of soil loss, it could temporarily degrade air
quality.
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Some ground surface disturbance would take place at assembly areas and day-use sites due to vehicle and
equipment movement, material storage, camping activity, and foot traffic. Since these areas would be
established at built-up or pre-disturbed sites, the effect on soil condition would be minor and transitory.
There would be a potential for a minor amount of soil loss due to wind erosion.
Implementation of the Proposed Action could cause contamination of soils within the project area. Vehicles
and equipment standing or parked at a site, could potentially leak fuel and POLs into the soil. Accidental
spills could also contaminate the soil.
Mitigation Measures
4.2.2
·
Vehicle speeds on unpaved roads would be restricted to 20 mph or less to control dust production and
prevent possible degradation of the roadbed. Vehicle speeds would be restricted to 5 mph or less in
assembly areas.
·
Marines would repair excessive damage to the roads.
·
All exercise participants would be briefed on acceptable use of the assembly areas and other sites, and
instructed to minimize damage to vegetation and soil surfaces.
·
No digging, trenching, or scrapping would be permitted at the assembly areas or other sites, other than
that required to prepare the river crossing site, remove contaminated soil, or to install radio grounding
equipment.
·
Material excavated from the access ramp at the river crossing site would be handled and stored in such a
way as to inhibit wind or water erosion.
·
A geotextile road base would be placed on the river entry and exit ramps to inhibit erosion from these
surfaces.
·
A drip pan or pad would be carried in each vehicle and placed beneath the oil pan every time the vehicle
is parked.
·
A spill contingency plan or standard operating procedure (SOP) would be in place and personnel trained
to respond to accidental spills. Spill kits would be carried by each unit.
·
Soil contaminated by an accidental spill would be excavated and disposed of as hazardous material. A
qualified archeologist would examine the site prior to excavation.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
Fewer unpaved roads would be used under the Reduced Route Alternative. This would result in less
damage to unpaved roadways and less soil loss through wind erosion. Although the amount of soil lost
would be insignificant, the amount of fugitive dust generation would increase (see air quality section
below). The elimination of routes also decreases the geographic distribution of vehicles during the exercise,
thus limiting any impacts to a smaller area. However, since no assembly areas are eliminated under this
Alternative, there would be no reduction in potential damage to soils at these sites.
Mitigation Measures
·
Same as for the Proposed Action.
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4.2.3
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Negative impacts to geology and soil resources under the Boat Launch Alternative would be similar to that
of the Proposed Action. There would be a slight reduction in potential bank erosion if either the Oxbow
boat ramp or the residential boat ramp were used.
Mitigation Measures
·
4.3
Same as for the Proposed Action.
WATER RESOURCES
Impacts to water resources are considered significant if one or more of the following significance criteria is
met: 1) surface water or groundwater is contaminated in excess of Federal or state water quality standards;
2) “Waters of the United States” are degraded by actions that exceed limits authorized under the Clean
Water Act; 3) wetlands and riparian zones are altered.
4.3.1
PROPOSED ACTION
Potential Impacts
Occupation of assembly areas and day-use sites by 2,200 Marines would increase the amount of water use
and waste generation within the project area.
Leaks and spills of fuel and POLs from parked vehicles could potentially contaminate surface water or
groundwater at sites near the Lower Colorado River. The lack of perennial surface water and the great
depth to groundwater makes it less likely that upland waters would be contaminated.
Boats used in the rafting and bridging operations could potentially leak fuel and POLs directly into the
river. The floating bridge “bays” do not use fuel or oil but do have parts that contain hydraulic fluid. As
with all watercraft, there is potential for small amounts of fuel or POLs to escape into the water; however,
the amount of incidental leakage would be small compared to the total release from the many powerboats
using the river. The impacts to water quality would be insignificant.
The greatest potential impact to water resources would be the accidental capsizing or sinking of a vessel,
bridge bay, or vehicle, especially one containing a fuel bladder. This could result in a release of
contaminants into river with negative impacts to aquatic life downstream.
Implementation of the Proposed Action would not negatively impact upland watercourses (washes) as all
vehicle traffic would be on established roadways. There would be no excavation or modification of BOR
stockpile sites (which occur in wash beds). During the river crossing operation, an access point would be
constructed on the west embankment. . Although no fill would be dredged from the river or discharged to
the river, there would be the potential for incidental fall back during the excavation. In addition, vehicle
traffic on the ramp could cause sediment to fall into the river.
No wetlands would be transited during this exercise. Wetland vegetation occurs in part of a small lagoon
(Hippie Hole) north of the bridgehead on the east side of the river. This area would be demarcated and
avoided during the river crossing activity.
Mitigation Measures
·
Water trucks would be used to supply water on site. No local water sources are required outside
MCAGCC or YPG.
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4.3.2
·
Portal toilets and waste receptacles would be provided and maintained by commercial contractors. All
sewage and waste material would be removed from the project sites and disposed of in the appropriate
manner.
·
In the event of bank damage below the high water mark at the river crossing, the Marines would
coordinate repair efforts with the Bureau of Reclamation.
·
A drip pan or pad would be carried in each vehicle and placed beneath the oil pan every time the vehicle
is parked.
·
Spill kits would be carried by each unit and used to soak up accidental spills on land.
·
A spill boom would be placed across the channel downstream from the rafting and bridging operation to
soak up accidental spills in the river.
·
Soil contaminated by an accidental spill would be excavated and disposed of as hazardous material. A
qualified archeologist would examine the spill site prior to excavation.
·
A spill contingency plan would be in place to deal with major spills. The Marines would coordinate
emergency spill response with local emergency services agencies prior to the exercise.
·
A geotextile road base would be placed on the river entry and exit ramps to inhibit erosion from these
surfaces.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
The Reduced Route Alternative would reduce the geographic distribution of the vehicle routes thereby
reducing the possibility of contaminant leaks or spills in those areas. Conversely, it would concentrate
potential water contamination along fewer routes. The potential negative impact to water resources in either
case is insignificant if proper mitigation measures are followed.
Mitigation Measures
·
4.3.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Same as for the Proposed Action.
Mitigation Measures
·
4.4
Same as for the Proposed Action.
TRANSPORTATION AND ACCESS
Impacts to transportation and access are considered significant if one or more of the following criteria is
met: 1) the safe movement of people, goods, and services is impaired; 2) access to private property or
public roads is denied; 3) transportation resources are damaged or taxed beyond their design capacity.
4.4.1
PROPOSED ACTION
Potential Impacts
The concerted movement of 600 military vehicles, in whole or in part, through the project area would
increase traffic on some sections of the proposed exercise route, primarily on the secondary road system.
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Since military vehicles would be operated at or below posted speed limits, traffic flows in some areas may
be slower than usual, inconveniencing some motorists. Sightseers may be attracted to the area by the
exercise, further congesting the road system.
Traffic control and safety are an integral part of this exercise. Marine drivers would comply with all
civilian traffic laws, as well as their own Standard Operating Procedures (SOPs) for traveling in convoy.
Military police would be deployed to control traffic flow. Access to public and private roads and property
would be kept open, although there could be minor delays while military vehicles move through an area.
Small sections of levee and embankment maintenance roads on BOR administered lands would be
temporarily inaccessible.
Heavily traveled routes that may experience traffic slowdowns are Highway 78 between Palo Verde and
Blythe, Highway 177 from Desert Center to Granite Pass, and Highway 62 at the intersection with
Highway 177 (Granite Pass Assembly Area).
Navigation on the Lower Colorado River would be impaired for two days during the rafting and bridging
operation. River transportation would be blocked from the Cibola Refuge boundary upstream to the Cibola
Bridge for 12 hours during daylight hours on each of these days; however, the river would remain open at
night (12 hours). There would be a slight reduction in public accessibility (about 2 hours each day for two
days) at the Oxbow boat ramp during the period the Marines were launching and landing their BEBs.
Transportation structures such as bridges, culverts, and roadways, could potentially be damaged if weight
limits are exceeded. Unpaved airstrips (e.g., YPG C-17 site) could also sustain damage from vehicle traffic.
Mitigation Measures
4.4.2
·
A traffic management plan would be developed and implemented in cooperation with local law
enforcement.
·
Military police and civilian law enforcement would provide traffic control at key points along the route.
·
A bridge permit would be obtained from the US Coast Guard and all the conditions and requirements
followed.
·
Public notifications would be published in local and regional newspapers and sent to local agencies and
organizations informing them of the routes and dates of the exercise, as well as the temporary closure of
the Lower Colorado River near Cibola. Notifications would be made at least 2 weeks prior to the start of
the exercise.
·
Signs would be posted at river entry points, campgrounds, and other sites up- and downstream of the
proposed river crossing site informing the public of the exercise and temporary closure of the Lower
Colorado River near Cibola. These signs would be prominently displayed and maintained for at least two
weeks prior to the exercise. The signs would suggest alternate access points to the River.
·
Provisions would be made for uncoupling the bridge in an emergency. Arrangements would be made
with civilian authorities to transport stranded boaters back to their vehicles in the event the River closure
separates them from their vehicles.
·
Any damage to transportation structures resulting from the exercise activities will be repaired by the
action proponent.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
The Reduced Route Alternative would eliminate exercise traffic over most of the unpaved roads on the
California part of the project area. This would tend to concentrate the vehicles on fewer (paved) routes.
However, given the rural nature of the unpaved roads, and the high traffic capacity of the paved roads
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(highways), it is unlikely that this Alternative would have any fewer or greater adverse impacts to
transportation and access than the Proposed Action.
Mitigation Measures
·
4.4.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Under the Boat Launch Alternative, the Marines would not be allowed to launch or land their boats using
the Oxbow Recreation Site boat ramp but would have to use either a private boat ramp a few miles
upstream or the east bank of the river crossing site. This alternative would reduce potential delay and
inconvenience to the recreational users of the Oxbow site, but could increase traffic problems at the
upstream residential area.
Mitigation Measures
·
4.5
Same as for the Proposed Action.
AIR QUALITY
Impacts to air quality are considered significant if an action produces exhaust emissions or fugitive dust in
excess of the limits established under the Clean Air Act and state air quality laws.
4.5.1
PROPOSED ACTION
Potential Impacts
The Desert Scimitar 02 exercise would generate air emissions associated with bridge construction and
vehicle movement. The largest single source of particulate air emissions would be the fugitive dust
associated with the vehicle movements over unpaved roadways. NOx, CO, PM10, SO2 and volatile organic
compounds would be emitted from vehicle, aircraft and watercraft exhaust. For air quality purposes, the
operation would cover a period of eleven days beginning April 22, 2002 (major vehicle traffic does not
begin until April 25). Table 12 lists the estimated air emissions for the Desert Scimitar 02 exercise. US
EPA-approved emission estimating techniques (e.g., AP-42) were used to estimate fugitive dust emissions
while EPA and California Air Resources Board (CARB) emission factors were used to estimate vehicle
exhaust emissions. See the Appendix for details.
Table 14. Air emissions predicted for Desert Scimitar 02.
Totals
Dust
(lbs)
77,364
PM10
Exhaust
(lbs)
180
Total PM-10
(lbs)
77,544
NOx
SO2
CO
(lbs)
1847
(lbs)
599
(lbs)
2445
VOC
(lbs)
398
Impacts to air quality are considered significant if an action produces emissions in excess of limits
established under the Clear Air Act and state air quality laws. The Desert Scimitar 02 exercise is unlike a
typical project that has a construction phase followed by long-term operation. Rather, this exercise would
produce air pollutant emissions over a short duration.
A portion of Desert Scimitar 02 exercise falls within the jurisdiction of the MDAQMD. The primary
concern of the MDAQMD is PM10. The MDAQMD significance level for PM10 is 15 tons/year. The total
PM10 emissions associated with the complete Desert Scimitar 02 exercise are approximately 35 tons, which
exceed the nominal MDAQMD significance level. However, not all of these emissions would occur within
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the MDAQMD and, if necessary, it is possible to re-route certain portions of the exercise to minimize
driving over unpaved portions of roads (which is a major contributor to the quantity of PM10 dust
generated). The same criteria can be applied to Imperial County and Arizona activities. Furthermore, since
all portions of the Desert Scimitar 02 exercise are in NAAQS attainment areas, Clean Air Act General
Conformity requirements do not pertain.
Overall, it is important to note that this exercise is mobile in nature, and that any of the impacts would be
short-term. As required by the MDAQMD regulations, since this exercise cannot be mitigated to a level
that is not significant, it would incorporate all feasible mitigation measures.
Mitigation Measures
4.5.2
·
All non-tactical portable engines and portable engine-driven equipment would be inspected and
maintained pursuant to the Statewide Portable Equipment Registration Program (California) and the
ADEQ portable source permit program. Military tactical equipment is generally exempt from the
Registration Program.
·
All fugitive dust control measures would be applied to minimize emissions as a result of the activities in
this exercise, particularly driving on unpaved roads and the construction involved with the bridge at the
river crossing. The fugitive dust control measures include wetting the dirt surfaces with water or EPAapproved wetting agents each day, prior to driving the dirt roads and bridgehead construction.
·
All required local permits and approvals would be obtained prior to construction and the conditions of
such approvals would be followed.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
The primary objective of the Reduced Route Alternative is to reduce travel over unpaved roads during the
exercise in order to reduce dust emissions. By eliminating the major unpaved roads in the California part of
the exercise, dust emissions are reduced from a calculated 35 tons over the 10 days of the exercise to 24
tons. This alternative has the potential to greatly reduce negative impacts of the exercise within Mojave
Desert Air Quality Management District jurisdiction.
Mitigation Measures
·
4.5.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
The Boat Launch Alterative would have the same impacts on air quality as the Proposed Action.
Mitigation Measures
·
4.6
Same as for the Proposed Action.
NOISE
Impacts are considered significant if one or more of the following criteria is met: 1) noise levels exceed
Federal and state noise limits; 2) noise levels are incompatible with other uses of the resource; 3) noise
levels adversely effect protected species in the project area.
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4.6.1
PROPOSED ACTION
Potential Impacts
Implementation of the Proposed Action would bring an additional 600 vehicles, several pieces of
construction equipment, and several motorboats and aircraft into the project area. Electrical generators and
other equipment would also be used. Ambient noise levels would increase when several of these vehicles
are operated in the same area at the same time. Excessive noise could annoy or inconvenience other users
of the public lands.
Much of the Proposed Action route is on highways and roads, military facilities, and recreation sites that
already experience relatively high levels of noise pollution. Parts of the route running through undeveloped
areas experience much less. Under the Proposed Action, assembly areas would be established away from
residential neighborhoods and public camp sites, and should not adversely impact residents or long-term
visitors. The area of greatest noise concentration produced by the Proposed Action would likely be at the
river crossing site, which already suffers noise pollution from recreational motorboat and jet-ski activity
(BLM 1994). A key concern here is the potential negative impact that the additional noise could have on
sensitive species in the area.
Aircraft noise should not be an issue as most of this would occur on MCAGCC and YPG. Helicopters
traveling between assembly areas would take place in established flight corridors. The number of helicopter
sorties between assembly areas would be relatively insignificant relative to normal military aircraft activity
in the area.
Mitigation Measures
4.6.2
·
Units would comply with Marine Corps regulations and SOPs regarding noise protection for workers.
·
Vehicles and equipment would be operated only when needed and shut down when not in use.
·
Assembly areas would be established away from residential communities, LTVAs, or other public sites
whenever possible.
·
The small lagoon, named “Hippie Hole,” located adjacent to the east bridgehead contains potential Yuma
Clapper Rail habitat. This area would avoided during the rafting and bridging operation.
·
Tactical movement of vehicles and use of construction equipment would only take place during daylight
hours.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
Restricting travel to paved roads on the California part of the project area would eliminate traffic noise in
the more rural routes. However, since these vehicles would be shifted to other routes, there would be a
greater concentration of traffic noise on fewer routes. Because in both cases the noise would take place
along established, and in most cases regularly traveled, roadways, the environmental impact would be
insignificant.
Mitigation Measures
·
4.6.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
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·
The Boat Launch Alternative would have similar noise impacts as the Proposed Action. By not allowing
the use of the Oxbow boat ramp, vehicle and boat engine noises would be reduced in this area during the
three days (2 hours each day) the BEBs would be deployed. However, the use of the boat ramp by the
public could produce as much engine noise. The BEB noise would simply be shifted to the residential
boat ramp upstream or to the east bank of the river.
Mitigation Measures
·
4.7
Same as for the Proposed Action.
BIOLOGICAL RESOURCES
Potential impacts to Threatened and Endangered species associated with the Proposed Action are evaluated
in the Biological Evaluation (BE) prepared pursuant to Section 7 of the ESA and applicable sections of the
CESA. The following section summarizes information provided by the BE related to native vegetation,
threatened and endangered species, and invasive weeds.
Impacts to biological resources are considered significant if: 1) habitat necessary for all or part of the life
cycle of a species is lost as a result of the action (e.g., lambing areas, migratory corridors, or wildlife
watering areas); 2) threatened or endangered plant and animal species are adversely affected; 3)
biodiversity is diminished; 4) invasive, non-native species are introduced to an area.
4.7.1
PROPOSED ACTION
Potential Impacts
Native Vegetation
Potential impacts to vegetation of are generally designated to be one of three types; short-term, long-term,
and permanent. Short-term impact is defined to be disturbance to a site from exercise activities wherein site
disturbance would require less than 10 years to return to a condition similar to that present before the
exercise occurred. An impact would be considered short-term if an activity required plants to be cut or
crushed but which kept soil disturbance to a minimum and left the roots and crowns intact. A long-term
impact would require more than 10 years to return to a pre-exercise condition. Activities that appreciably
affect soil conditions, disturb the root zone, or result in the removal of the basal crown would be considered
a long-term impact. A permanent impact would last into the foreseeable future (e.g. laying of pavement).
Special consideration was given to the choice of sites for each activity in order to fully minimize the
potential impacts to vegetation. All impacts to areas used in the exercise are expected to be short term.
Assembly Area and Command Posts. Assembly areas and command post areas were carefully chosen to
reduce impact to native vegetation. In general, these areas would be located in BLM visitor areas
(campgrounds), BOR stockpile yards, county park land, private farmland, and similar areas or in areas
where previous use has left habitat in a highly disturbed condition. These include the Yuma Proving
Ground sites, two airports (Blythe, CA and Desert Center CA, respectively) and Metropolitan Water
District (MWD) property. The impact to native vegetation at these areas would be short-term if any impact
is sustained at all, due to denuded nature of each site. Short-term impacts that could occur in these areas
might be accidental trampling of young annuals or perennial vegetation.
Transportation Corridors and Engagement Areas. Transportation corridors and engagement areas are
comprised of existing paved and improved surface (dirt) roads frequently used by the general public. The
impact if any to these areas would be short-term and most likely in areas that are adjacent to roadways such
as dirt shoulders or pullouts. Mainly small annuals growing on the roadside may be crushed accidentally in
such areas.
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Colorado River Crossing Site. The river crossing site was chosen not only for its applicability to the
exercise but also to minimize disturbances to high quality plant habitats. While the area on both sides of the
river is densely covered with plant life it is predominated by tamarisk infestation that has all but completely
replaced the native vegetation in most every location. There are small stands of native rushes in the Bureau
of Reclamation (BOR) dredge slip or “Hippy Hole” on the Arizona side of the river and arrow weed was
observed in the areas slated for activity. Impacts to the tamarisk and native arrow weed would most likely
be short-term; however, cutting and removal would take place only on the California side of the crossing
site. There would be no impacts to the rushes as the area would be off limits. There is a possibility that
some native plants may be crushed or trampled or cut in the coarse of preparing the riverbanks for the
bridge but the effects if any would be short-term.
Federally and State Listed T&E Species
Substantially the same project was the subject of formal consultation with the US Fish and Wildlife Service
(USFWS) before Desert Scimitar 01. USFWS representatives concurred with the findings of the 2001
Biological Evaluation in that the project is either unlikely to affect or may, but is not likely to adversely
affect desert tortoise (Gopherus agassizii), razorback sucker (Xyrauchen texanus), Yuma clapper rail
(Rallus longirostris yumanensis), southwestern willow flycatcher (Empidonax traillii extimus) and
Coachella Valley milk-vetch (Astragalus lentiginosus var. coachellae). The BE determined that other
special status species were found to have no potential impact from the project. It is not anticipated that this
finding would be changed from last year when consultation is concluded and a biological opinion is issued.
Yuma Clapper Rail. Potential Impacts: Potential impacts could occur to Yuma clapper rail primarily at the
River Crossing site on the Arizona Side of the River and in the irrigation ditches at Palo Verde. The
northern portion of the BOR dredge slip contains a small stand of rushes that could potentially serve as
cover for rails during breeding and/or nesting season, likewise the irrigation ditches may provide similar
cover. There would be no disturbance to the rushes; however, noise from the activity may upset the bird’s
behavior. The noise and disturbance from the Marines activities is likely to be far less than or not
appreciably greater than that exhibited by normal recreational use of the area by speed boats and campers.
Razorback Sucker. Potential Impacts: Given current location records for the species, it is unlikely that the
razorback sucker occurs in the Cibola stretch of the Lower Colorado River, where the bridging and rafting
exercises would occur. Juveniles, if they do exist in this stretch of the river may use the warm calm
backwaters of the BOR dredge slip for cover. Boating on the river is common in this area during spring,
summer, and fall and the area is used as an unofficial boat launch with people launching vessels off the
beach area into the lagoon. It is, however, that intermittent and the nearly continual activity of the rafting
exercise over two consecutive days could conceivably cause some additional disturbance to the species, if it
were present; however, it is unlikely given the reported level of recreation activity in the area. (Note: the
BLM Yuma Field Office Biologist has reported that Arizona Game and Fish has released razorback sucker
hatchery stock into the “A-7 Backwater” and that individuals may be present in the Cibola area. The U.S.
Fish and Wildlife Service did not consider this a factor in their Biological Opinion).
Southwestern Willow Flycatcher. Potential Impacts: There is questionable and, at best, very poor nesting
habitat for southwestern willow flycatcher at the Lower Colorado River crossing site. In the unlikely event
that the species is present, it could be affected by the length and intensity of the rafting exercise at the
Cibola river crossing. It is unlikely that noise levels from the exercise would have a negative effect,
because boating is common in this area during spring, summer, and fall, and decibel levels from the boat
crossing and bridge-building exercise are likely to be less than for recreationists’ speed boats.
Desert Tortoise. Potential Impacts: the most likely impacts to tortoise may be disruption of normal
activities and potential death or injury due to vehicle movement in the habitat. Tortoises may seek shade
underneath parked vehicles and be injured or killed as result of the vehicle moving, or be struck by a
vehicle while it is moving in the roadway. It is unlikely that tortoises would be impacted by noise from the
activities as areas of high use are removed from tortoise habitat. No habitat would be lost or altered as a
result of this project.
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No critical habitat for the desert tortoise exists on the project route except along portions of I-10,
Chuckwalla Road, Highway 62 and 95 (Vidal/Vidal Junction), and Wiley Well / Milpitas Wash Road
(USFWS 1994a). Additionally, this project would not present a conflict with the Desert Tortoise Recovery
Plan (USFWS 1994b). All Desert Wildlife Management Areas (DWMA’s), where recovery actions are
concentrated in order to promote “the long-term persistence of viable desert tortoise populations and the
ecosystems upon which they depend”, are outside the project route. One segment of the exercise route,
Wiley Well/Milpitas Wash Road, traverses the proposed Chuckwalla DWMA however the exercise is not
inconsistent with DWMA management prescription. Due to the anticipated low densities in most of the
areas and/or the proposed mitigation, impacts to tortoises should be minor to negligible.
Coachella Valley Milk-Vetch. Potential Impacts: the potential exists to impact the plant by accidental
crushing, trampling or inadvertent cutting. Habitat exists for the plant only along the California Highway
177 route and potentially at the Desert Center Airport and Cal Trans Stockpile (Postmile 10) sites.
Sonoran Population of Desert Tortoise
Potential Impact: As with the Mojave population, the most likely impacts to Sonoran population desert
tortoise may be disruption of normal activities and potential death or injury due to vehicle movement in the
habitat. However, because the Sonoran population prefers rocky habitats in mountainous areas (i.e., away
from most roads) and has a relatively low population density within the project area, it is unlikely that these
animals would be encountered during the exercise. Although the Sonoran population is not a Federally or
state listed species, similar measures would be implemented to avoid disturbing any individuals
encountered during the exercise.
Wild Horses and Burros
Potential Impact: the potential exists to adversely impact these BLM special management species by
blocking their movement corridors and access to water, or by accidental collisions resulting in injury or
death. Horses and burros are most likely to be encountered in the area between the River Crossing (e.g.,
along Cibola Lake Road and Ehrenberg Wash Road) and the Cibola (C-17) Assembly Area on Yuma
Proving Ground, especially where large washes cross the road (e.g., Gould Wash, Crazy Woman Wash,
Ehrenberg Wash, and Mule Wash). They are most active early in the morning and late in the evening.
Desert Bighorn Sheep
Potential Impact: the potential exists to adversely impact Desert or Nelson’s bighorn sheep by disruption of
normal activities and potential death or injury due to vehicle and helicopter movement in the habitat. Desert
bighorn sheep are most likely to be encountered in the passes of the project route between the River
Crossing and Yuma Proving Ground. Although the Arizona population is not a Federally listed or Arizona
state protected species measures would be implemented to avoid disturbing any individuals encountered
during the exercise.
Invasive Non-Native Plants
Potential Impact: The introduction of invasive non-native plant seeds is a potential impact of this exercise.
Actions related to the exercise may aggravate existing conditions. Soil and seed may be transported on
equipment along the exercise corridor. Equipment brought in from other locations may harbor seeds as
well. Invasive non-native plant seed is most likely to gain a foothold when soil is disturbed. Noxious
species in place at the time of the exercise may benefit from ground disturbing activities and spread.
Mitigation Measures
Native Vegetation
At proposed exercise sites, the following mitigation measures would apply:
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·
Vehicles would not be driven over vegetation, particularly cactus species, and would avoid wooded wash
areas and vegetated drainages.
·
Vehicles would be parked only on denuded or paved areas.
·
Vehicles would be driven only on graded and/or improved road (paved or dirt) surfaces and would use
only existing pullouts for parking.
·
Trees or other plants would not be used for tent anchors or other similar devices.
·
At the river crossing site, Marines would avoid rushes in lagoon area. Any broken tamarisk branches
would be dispersed over the area to reduce risk of fire.
·
At YPG, Marines would follow existing operating procedures regarding environmental protection.
Federally and State Listed T&E Species
Yuma Clapper Rail.
·
All elements of the exercise would remain at least 15 m (50 feet) from the rushes at Hippie Hole and
from any irrigation canals and drainages in the Palo Verde Area. The D-7 tractor on the Isthmus road at
Hippie Hole may be closer than 15m but would be driven to the area and not moved or operated until it is
removed from the road when the exercise is completed.
·
No boats would be allowed in the northern and western portion of the lagoon area at Hippie Hole,
maintaining a distance of 15m(50 feet) from rushes at all times. Activity would be limited to boat storage
and operation of the boat motors would be limited to ingress and egress from the lagoon.
·
Hours of operation of heavy equipment would be from 6 AM to 6 PM only.
Razorback Sucker.
All elements of the exercise would remain at least 15 m (50 feet) from the rushes at Hippie Hole and
from any irrigation canals and drainages in the Palo Verde Area. The D-7 tractor on the Isthmus road at
Hippie Hole may be closer than 15m but would be driven to the area and not moved or operated until it is
removed from the road when the exercise is completed.
·
·
No boats would be allowed in the northern and western portion of the lagoon area at Hippie Hole,
maintaining a distance of 15m(50 feet) from rushes at all times. Activity would be limited to boat storage
and operation of the boat motors would be limited to ingress and egress from the lagoon.
Southwestern Willow Flycatcher.
Removal of native tree species at the river crossing site would be minimized to ten or less tamarisk
individuals on the California side of river crossing site.
·
·
Hours of operation of heavy equipment would be from 6 AM to 6 PM only.
Conclusion: Desert Scimitar 02 is unlikely to affect, and would not adversely affect, the southwestern
willow flycatcher.
Desert Tortoise.
Due to the possibility that tortoises may be present at some sites during the exercise, several mitigation
measures are targeted for those areas. Each is discussed below, in addition to general mitigation actions for
this species.
General Mitigation Actions
·
Maximum vehicle speeds would be limited to 45 mph on paved roads other than freeways, and 20 mph
on non-paved roads.
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·
A pre-exercise briefing on desert tortoise awareness would be presented to all participants in the exercise.
The program would include:
a. Distribution of the desert tortoise
b. General behavior and ecology of the desert tortoise
c. Sensitivity to human activities
d. Legal protection and penalties for violations
· The authorized biologist would also train a select group of Marines to be designated as tortoise spotters.
These Marines would be trained to identify tortoises and the procedure for contacting the authorized
biologist if a tortoise is encountered. A minimum of one of the specially trained Marines would
accompany all vehicles moving on dirt roads and be present at all Command Centers, Assembly areas,
and radio retransmission sites.
·
A sticker advising all participants to look under vehicles prior to moving would be affixed to the steering
wheel or dash.
·
Only biologists authorized by the USFWS, CDFG, and the BLM shall handle desert tortoises. The BLM
or project proponent shall submit the name(s) of proposed authorized biologist(s) to the USFWS for
review and approval at least 15 days prior to the onset of activities. No handling activities shall begin
until an authorized biologist is approved. Authorization for handling shall be granted under the auspices
of the Section 7 Consultation.
·
The area of disturbance shall be confined to the smallest practical area, considering topography,
placement of facilities, location of tortoise burrows, public health and safety, and other limiting factors.
Work area boundaries shall be delineated with flagging or other marking to minimize surface disturbance
associated with vehicle straying. Special habitat features, such as burrows, identified by the qualified
biologist shall be avoided to the extent possible. To the extent possible, previously disturbed areas within
the project site shall be utilized for the stockpiling of excavated materials, storage of equipment, location
of office trailers, and parking of vehicles. The qualified biologist, in consultation with the project
proponent, shall ensure compliance with this measure.
·
Except when absolutely required by the project and as explicitly state in the project permit, cross-country
vehicle use by Marines and contractor support is prohibited.
·
Desert tortoises may be handled only by the authorized biologist, and only when necessary. In handling
desert tortoises, the authorized biologist shall follow the techniques for handling desert tortoise in
“Guidelines for Handling Desert Tortoises during Construction Projects” (Desert Tortoise Council 1996).
·
The authorized biologist would maintain a record of all desert tortoises handled. This information would
include the following for each tortoise:
a.
b.
c.
d.
e.
The locations (narrative and maps) and dates of observations
General condition and health, including injuries and state of healing and whether animals voided
their bladders
Location moved from and location moved to
Diagnostic marking (i.e. identification numbers or marked lateral scutes)
Slide photograph of each desert tortoise handled as described in a previous measure
·
No later than 90 days after completion of activities, the authorized biologist would prepare a report for
the BLM. The report would document the effectiveness and practicality of the mitigation measures, the
number of tortoises excavated from burrows, the number of tortoises moved from the site, the number of
tortoises killed or injured, and the specific information for each tortoise as described previously. The
report may make recommendations for modifying the stipulations to enhance tortoise protection or to
make it more workable. The report shall provide an estimate of the actual acreage disturbed by various
aspects of the operation.
·
Upon locating a dead or injured tortoise, the project proponent or agent is to notify the BLM Resource
Area Office. The authorized biologist must then notify the appropriate field office (Carlsbad or Ventura)
of the USFWS by telephone within three days of the finding. Written notification must be made within
five days of the finding, both to the appropriate USFWS field office and to the USFWS Division of Law
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Enforcement in Torrance. The information provided must include the date and time of the finding or
incident (if known), location of the carcass or injured animal, a photograph, cause of death, if known, and
other pertinent information.
·
An injured animal shall be transported to a qualified veterinarian for treatment at the expense of the
project proponent. If an injured animal recovers, the appropriate field office of USFWS should be
contacted for final disposition of the animal.
·
All trash and food items shall be promptly contained within closed, raven-proof containers. These would
be regularly removed from the exercise area site to reduce the attractiveness of the area to ravens and
other tortoise predators.
·
The authorized biologist would conduct a 100% clearance survey for desert tortoises for each maneuver,
staging, assemblage, exercise, or any other area in which activities would be taking place outside of the
road berm. This survey would take place 24 to 48 hours prior to the onset of field activities using the
Service-recommended desert tortoise presence survey protocol . Use areas for exercise would be flagged
in order to delineate boundaries.
·
All tortoises observed by any personnel associated with this project shall be reported immediately to the
authorized biologist. The authorized biologist would move the desert tortoise off-site into adjacent
undisturbed desert tortoise habitat if it is in imminent danger.
·
Vehicle operators would inspect for desert tortoises under vehicles prior to moving any vehicle. If a
desert tortoise is present, the authorized biologist would carefully move the desert tortoise in accordance
with the protocol outlined in this report (see below). If this is not possible, the vehicle operator would
carefully move the vehicle only when necessary and when the desert tortoise would not be injured by the
moving vehicle. A person would be posted near the desert tortoise while the rest of the convoy drives by
to ensure the desert tortoise stays out of harms way.
Blythe Airport
·
Clearance surveys would be conducted prior to occupation of the site by any element of the exercise.
·
A biological monitor, trained to handle tortoises, would be onsite or available by radio during any
military occupation of the site.
·
All vehicles would be parked on paved areas or designated disturbed dirt areas. Camping may occur in
dirt areas flagged for such use.
Midland Engagement Area – Midland LTVA, area near Midland Town site, Landfill, Palen Pass Road,
Wiley’s Well / Milpitas Wash Road.
·
Clearance surveys would occur prior to occupation of the site by any element of the exercise.
·
Roads approved for the tactical maneuvers are defined as maintained roads with berms. These roads
would be designated by a biological monitor and flagged prior to the maneuvers. Travel on two-tracks
and trails would not be permitted.
·
A biological monitor trained to handle tortoises would be available at all times during military
occupation of the Midland Engagement Area. A contingent of Marines would be specially trained by an
approved biological monitor to precede all vehicle convoys on dirt roads and to patrol the areas around
the LTVA, near the Town site and the Landfill site and in any area that tortoises may be present in order
to spot any tortoise that may be in harm's way. The Marine monitors would precede vehicles involved in
the maneuvers at a distance sufficient to keep tortoises from being crushed by military vehicles.
Tortoises would be moved offsite by the approved handling monitor to a distance sufficient to ensure the
tortoise’s safety. Alternatively, the tortoise may be temporarily held until maneuvers are finished. The
collection, holding, and translocation of tortoises would comply with the following protocol:
1.
If the daily surface temperature maximum remains below 43° C (109° F), tortoises may be moved
offsite, up to 400 m (1300 ft) from the capture point, to a shaded shrub or burrow (juvenile tortoises
may be moved up to 100 m (330 ft) from the capture point).
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2.
If temperatures are warmer than 43° C (109° F), or if tortoises require holding to ensure their safety
during maneuvers, then tortoises should be held in the shade, at air temperatures between 25° and
30° C (77° and 86°F). Immediately following the completion of the military exercise and after
ground temperatures have dropped below 42° C (108° F), the tortoises would be released to a shaded
burrow or site at the point of capture.
3.
Juvenile tortoises would not be released at dusk, but would be held and released at dawn.
4.
Tortoises would be handled smoothly, quickly, and with clean techniques. Clean techniques would
include the use of disposable surgical gloves and all instrumentation coming into contact with
tortoises would be disinfected with either bleach or alcohol. Tortoises would be put in a sterilized
tub. Tubs would be padded and vehicle speed minimized on dirt roads if tortoises need to be
transported by vehicle.
Coachella Valley Milk-Vetch.
·
Habitat may exist for the Coachella Valley milk-vetch near the Desert Center Airport Assembly Area and
Cal Trans Stockpile Command Post. Pre-exercise surveys would be conducted to determine the presence
of the species. These surveys would include not only the assembly areas and command posts, but all road
berms that may be affected during the exercise. If any Coachella Valley milk-vetch plants are found,
populations would be flagged for avoidance.
·
Marines would be briefed on the plant and its identification and instructed to avoid.
Sonoran Population of Desert Tortoise
·
Maximum vehicle speeds would be limited to 45 mph on paved roads other than freeways, and 20 mph
on non-paved roads.
·
A pre-exercise briefing on desert tortoise avoidance measures would be presented to all participants in
the exercise.
·
A sticker advising all participants to look under vehicles prior to moving would be affixed to the steering
wheel or dash.
Wild Horses and Burros
·
Marines would be briefed on appropriate actions to take if horses or burros are encountered, including
prohibitions against chasing or harassing the animals.
·
Marines would stop and allow horses and burros to cross roads.
Desert Bighorn Sheep
·
Marines would be briefed on appropriate actions to take if bighorn sheep are encountered, including
prohibitions against approaching, chasing or harassing the animals.
·
Helicopters would be limited to flying at 500 feet and above except when landing and taking off. In
lambing areas identified by BLM, Yuma helicopter activity would be limited to flying at 3000 feet and
above.
Invasive Non-Native Plants
·
All vehicles and pieces of equipment would be washed prior to leaving their duty locations whether that
be MCAGCC or Camp Pendleton or elsewhere and leaving for YPG.
·
Encrusted mud or dirt would be washed from heavy equipment before transporting it back to home base.
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The No Action Alternative would result in no potential impact.
General Mitigation Measures
Applying to all areas of the exercise and benefiting several plant and animal species:
4.7.2
·
Parking, staging areas, command posts and assembly areas would only occur in designated areas. Such
areas would be staked to mark boundaries. There would be no “off-road” travel, or use of “tracks” during
this exercise except within parking sections of assembly areas.
·
Riverbank disturbances would be minimized. Activities would be limited to cleared areas, including
roads, or tamarisk-covered areas.
·
Dirt and rocks would be stockpiled only on existing compacted fill roads or in tamarisk-covered areas.
·
Noise would be minimized at all times and particularly during the bridge building and rafting exercise.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
Implementation of the Reduced Route Alternative would reduce the potential negative impact to desert
tortoise along the unpaved routes. Implementation of the Reduced Route Alternative would decrease the
risk of transporting invasive non-native plants as a result of decreased travel on unpaved roads.
Mitigation Measures
·
4.7.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Implementation of the Boat Launch Alternative or either of the two optional boat launch locations (see
section 2.3 above) is not expected to have a significant impact on threatened and endangered species.
Mitigation Measures
·
4.8
Same as for the Proposed Action.
CULTURAL RESOURCES
Implementation of the preferred alternative would have a significant impact if one or more of the following
criteria is met: 1) prehistoric and historic sites eligible for the National Register of Historic Places (NRHP)
are adversely affected; 2) Native American religious or other cultural properties are misused.
4.8.1
PROPOSED ACTION
Potential Impacts
Archival research and a physical survey were conducted for each of the proposed routes and use areas per
Code of Federal Regulations (CFR) 36 CFR Part 800. The only cultural resource observed within the
project area was one crude preform biface isolate recorded on the Ulmer property in the Palo Verde area. A
cultural site occurs near the route to the Big Maria communication site but is not likely to be impacted by
the exercise. Based on the lack of historic properties, it is concluded that the proposed Desert Scimitar 02
exercise would have no effect on cultural resources.
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Consultation with Native American tribes associated with the areas proposed for this exercise has been
completed. No comments or concerns have been received.
Mitigation Measures
·
4.8.2
A traffic management plan would be implemented. All travel would be confined to authorized
established roads. The effect to the ground surface in all cases, would be that of normal wheeled-vehicle
operation only. Tracked vehicles would not be utilized and traffic laws and speed limits would be
enforced by military police.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
Implementation of the Reduced Route Alternative would reduce the likelihood of potential damage to
buried, undiscovered, cultural resources along the eliminated unpaved routes in California. However, since
there would be no assembly areas along these routes, the reduction would not be significantly different than
the potential impact caused by the Proposed Action.
Mitigation Measures
·
4.8.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
The Boat Launch Alternative would have the same potential negative impacts to cultural resources as the
Proposed Action. All areas proposed for boat launching and landing sites have been highly disturbed and
are unlikely to contain historical or prehistoric artifacts.
Mitigation Measures
·
4.9
Same as for the Proposed Action.
PALEONTOLOGICAL RESOURCES
Implementation of the preferred alternative would have a significant impact on paleontological resources if
one or more of the following criteria is met: 1) fossils and other paleontological resources are removed
from a site without authorization; 2) Paleontological resources are damaged by off-road activities.
4.9.1
PROPOSED ACTION
Potential Impacts
No specific data were provided in agency planning documents regarding paleontological resources in the
Action area, except for the presence of petrified wood on YPG (USAYPG 1998). No concerns were raised
during initial scoping that this may be a concern. Because all activities would take place on roads and predisturbed sites, it is unlikely that implementation of the Proposed Action would have any significant impact
on paleontological resources.
Mitigation Measures
·
As part of their general briefing (and specific YPG briefing) Marines would be instructed not to pick up
or disturb fossils, petrified wood, or other paleontological specimens.
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4.9.2
REDUCED ROUTE ALTERNATIVE
Potential Impacts
Implementation of the Reduced Route Alternative would reduce the likelihood of damage to
paleontological resources along the eliminated unpaved routes in California. The potential impact of this
Alternative would not be significantly different from the Proposed Action.
Mitigation Measures
·
4.9.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Potential impacts to paleontological resources would be the same under the Boat Launch Alternative as the
Proposed Action.
Mitigation Measures
·
4.10
Same as for the Proposed Action.
RECREATION/VISITOR SERVICES
Impacts to recreation and visitor services are considered significant if one or more of the following criteria
is met: 1) recreational access to public lands and waterways is blocked or severely diminished; 2)
recreational areas or facilities are irreparably damaged; 3) new river access points are created that
encourage damage to the area.
4.10.1
PROPOSED ACTION
Potential Impacts
Implementation of the Proposed Action could result in adverse impacts to recreation and visitor services in
the project area, primarily at the Lower Colorado River crossing site and the nearby BLM Oxbow
Recreation Site. Upstream and downstream boat traffic would be blocked at the Cibola crossing site during
the two days of rafting and bridging operations, 29 and 30 April. The river would be totally blocked for 12
hours each day and opened again each night. Recreational users who were not informed of the activity or
chose to ignore public notifications could be temporarily separated from their boat launch or marina. The
rafting and bridging operations could also pose a navigation hazard to watercraft not aware of the presence
of the bridge.
Fisherman and other shore users may be temporarily inconvenienced during the pre- and post-crossing
construction activity at the east and west bridgeheads, in addition to the crossing operation itself. The
Marines have applied for a permit to use the Palo Verde County Park for several days during the exercise.
This may temporarily displace other visitors wanting to use the site. However, because assembly areas and
staging sites would typically be established on degraded land, or less-used camping sites, it is unlikely that
there would be significant conflict between military and civilian use of the recreation resource. Any
negative impact that did occur would be transitory and of short duration.
Vehicle travel, camping, and other activities at assembly areas could result in damage to vegetation, road
surfaces, and the ground surface, as well as damage to sites adjacent to the assembly areas. Although all the
proposed assembly areas occur on pre-disturbed land (in some cases severally disturbed land) there is a risk
that further damage could result from this exercise.
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Both the Midland LTVA (CA) and Roadrunner Assembly Area (AZ) are examples of recreation sites that
receive heavy use by the public. This includes use by trucks, jeeps, recreational vehicles, and large motor
homes. This use has compacted the ground surface and inhibits the growth of vegetation on the sites. It is
highly unlikely that military vehicles, when operated at low speed and in accordance with land use
conditions, would have any significant additional impact on this resource. The proposed action would not
require the cutting or removal of any vegetation from these areas.
No significant increase in recreational access to the river would occur because of the Proposed Action. A
permanent access ramp would be constructed into the west bank. Access roads and a boat ramp already
exist on the east bank, and the public would likely continue to use these areas after the exercise.
Mitigation Measures
4.10.2
·
Public notifications would be published in local and regional newspapers, and sent to local agencies and
organizations informing them of the routes and dates of the exercise, as well as the closure of the Lower
Colorado River near Cibola. Notifications would be made at least 2 weeks prior to the start of the
exercise.
·
Signs would be posted at river entry points, campgrounds, and other sites up- and downstream of the
proposed river crossing site informing the public of the exercise and temporary closure of the Lower
Colorado River near Cibola. These signs would be prominently displayed and maintained for at least two
weeks prior to the exercise. The signs would suggest alternate access points to the River.
·
Marines would be instructed to protect vegetation and ground cover in the assembly areas and day use
sites; there would be no need to cut or remove vegetation from these sites. Vehicle movement off those
sites would be prohibited. Any damage done would be repaired at the expense of the action proponent.
·
Any damage to road surfaces as a result of the increased vehicle traffic in these areas would be repaired
by the action proponent.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
The Reduced Route Alternative would have the same impact on recreation / visitor resources as the
Proposed Action.
Mitigation Measures
·
4.10.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Implementation of the Boat Launch Alternative would reduce the potential negative impact to recreation at
the Oxbow Recreation Site.
Mitigation Measures
·
4.11
Same as for the Proposed Action.
PUBLIC SERVICES AND UTILITIES
Impacts to public services and utilities are considered significant if one of the following criteria is met: 1)
access to public services or utilities (water, gas, electricity, communication) is impaired to the point of
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endangering human health or property; 2) utility systems are damaged; 3) radio communication is
disrupted.
4.11.1
PROPOSED ACTION
Potential Impacts
Implementation of the Proposed Action would increase the amount of ground and air traffic in the project
area. This would increase the chance that a vehicle or aircraft might accidentally strike and damage an
overhead utility line, or that a heavy vehicle might damage a buried pipeline. However, because all vehicle
travel would be on established roads, or in approved assembly areas and staging sites, the chance of
accidental damage to overhead or buried utilities is minimal. Aircraft (helicopters) would use FAA
approved flight corridors and land only at approved assembly areas (many of which have established
landing facilities). No digging or excavation (other than at the river crossing site, and for radio equipment
grounding) would be conducted during the exercise.
Logistical support is a key component of the proposed exercise. Water, electricity, sewage, and waste
collection services would be provided by the Marine units themselves or by outside contractors. There
would be no additional stress to the local services and utility systems.
There would be a heavy use of radio communication during the exercise. Portable retransmission systems
would be established within the approved assembly areas or staging sites, or at existing communication or
utility sites (radio towers, water towers). There is a potential for military radio traffic to interfere with
civilian communication.
Mitigation Measures
4.11.2
·
All required services (water, portable toilets, waste collection) would be provided by the Marines or by
commercial contractors. All waste materials would be removed from the sites.
·
Authorization would be obtained from landowners before using communication facilities for retrans sites.
·
Notification would be sent to owners of existing communication facilities about possible interference
from military radio traffic in the area.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
The potential impacts of the Reduced Route Alternative on public services and utilities would be similar to
that of the Proposed Action.
Mitigation Measures
·
4.11.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
The potential negative impacts of the Boat Launch Alternative on public services and utilities would be
similar to that of the Proposed Action on the routes remaining in the exercise.
Mitigation Measures
·
Same as for the Proposed Action.
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4.12
HAZARDOUS MATERIALS
Impacts caused by hazardous materials are considered significant if one of the following criteria is met: 1)
hazardous materials are not handled according to Federal and state regulation; 2) hazardous materials are
improperly disposed of or allowed to contaminate the environment.
4.12.1
PROPOSED ACTION
Potential Impacts
Implementation of the Proposed Action would introduce 600 vehicles, plus watercraft, aircraft, and other
mechanical equipment to the project area. Fuels and POLs would be the primary hazardous materials of
concern. This material would be stored and used according to Federal and state regulations. Material Safety
Data Sheets would be available for all hazardous materials used in the exercise.
Standard operating procedures would be followed when handling hazardous materials. Each vehicle would
carry a drip pan or pad to place under the vehicle when parked. In addition, refueling vehicles would be
underlain by a secondary containment system (liner) when parked for extended periods. No refueling,
repair, or lubricating would be allowed within 150 feet of a stream or wash. Each unit would carry a spill
kit to cleanup minor spills. A project Spill Prevention Control and Countermeasures Plan (SPCCP) would
be developed and made available during the exercise. The project Spill Response Team would coordinate
their response plan with local emergency services agencies and response teams at YPG, MCAGCC, and
MCASY.
Mitigation Measures
4.12.2
·
Hazardous materials would be handled according to SOPs.
·
Hazardous material spills would be responded to per the SPCCP.
·
Any contaminated soil or other material would be removed from the site and disposed of accordingly.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
Implementation of the Reduced Route Alternative Proposed Action would eliminate the risk of potential
leaks and spills on the unpaved routes excluded from the exercise. Other potential impacts are similar to
those of the Proposed Action.
Mitigation Measures
·
4.12.3
Same as for the Proposed Action.
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Implementation of the Boat Launch Alternative would have the same potential impacts from hazard
materials as the Proposed Action.
Mitigation Measures
·
Same as for the Proposed Action.
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4.13
SOCIOECONOMICS
Impacts to socioeconomic factors are considered significant if one or more of the following criteria is met:
1) there is a measurable, long-term increase in the local population or economic well being of the
community; 2) there is a measurable, long-term decrease in the local population or economic well being of
the community.
4.13.1
PROPOSED ACTION
Potential Impacts
Marine units would carry all their fuel, provisions, and gear with them into the exercise area. However,
they would arrange with local contractors to provide portable toilet and waste-bin services at the assembly
areas. The cost for these services is estimated at $57,800.00. It is anticipated that Marines participating in
Desert Scimitar 02 would use some of their own money to make small purchases at local businesses
(convenience stores and restaurants, primarily in the communities of Palo Verde, Blythe, and Desert
Center. If it is assumed that if each of the 2,200 Marines participating in this exercise spent, on average,
$10.00 in local establishments, the total amount expended would be $22,000.00. Thus Desert Scimitar 02
has the potential to introduce $79,800.00 to the local economies in the California part of the project area.
This does not include the potential amount spent by invited guests, media representatives, and the general
public who come to view the river crossing. Because of the transitory nature of Desert Scimitar 02, there
would likely be no long-term positive or negative impacts to the local population or economy.
Under the Proposed Action, use of the Oxbow Recreation Site boat ramp for launching and landing BEBs
could discourage the general public from using the site and therefore reduce user fees collected by BLM. If
the combined weight of the BEB and BEB carrier exceed the capacity of the concrete boat ramp, there
could be permanent damage to the structure and ultimate loss of revenue to the BLM, as potential
recreational users of the site would move elsewhere.
Mitigation Measures
4.13.2
·
Use of Oxbow Recreation Site boat ramp would be limited to 2 hours in the morning (around sunrise)
and 2 hours in the evening (sunset) on four weekdays during the setup and deployment of the ribbon
bridge.
·
No equipment or materials would be staged at the Oxbow campground (no restriction on public access to
the camping space).
·
Marine engineers would examine and verify the load capacity of the Oxbow boat ramp to ensure it would
not be damaged by the boat carriers.
·
Should damage occur, the Marines would repair or pay to repair the damage as quickly as possible to
ensure continued public access to the boat ramp.
REDUCED ROUTE ALTERNATIVE
Potential Impacts
Implementation of the Reduced Route Alternative would have no impact on socioeconomic factors beyond
the Proposed Action as most of the money would be expended in the urbanized areas.
Mitigation Measures
·
Same as for the Proposed Action.
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4.13.3
BOAT LAUNCH ALTERNATIVE
Potential Impacts
Moving the BEB launching/landing activity to a site other than the Oxbow Recreation Site boat ramp may
reduce the potential loss of revenue to the BLM at this fee use area. The Oxbow ramp would remain
available for public use throughout the day and there would be no potential for damage to the ramp from
Marine vehicles.
Mitigation Measures
·
4.14
Same as for the Proposed Action.
CUMULATIVE IMPACTS
The Council on Environmental Quality’s (CEQ) regulations (40 CFR §§ 1500 – 1508) implementing the
procedural provisions of the National Environmental Policy Act (NEPA) of 1969, as amended (42 U.S.C.
§§ 4321 et seq.), defines cumulative effects as:
The impact on the environment which results from the incremental impact of the action when
added to other past, present, and reasonably foreseeable future actions regardless of what agency
(Federal or non-Federal) or person undertakes such other actions (40 CFR § 1508.7).
Desert Scimitar 02 planners and cooperating agencies have made a great effort to identify routes and sites
that would be least impacted by the proposed exercise. As specified in the discussion above, most of the
vehicle travel would be on paved highways and roads, and the rest would be on maintained unpaved roads.
The assembly and staging areas would be established on pre-disturbed sites which, in many cases, have
minimal value for other uses. The use of these roads and sites would not affect the long-term use of these
resources by others. The cumulative impact of implementing either the Proposed Action or the Reduced
Route and Boat Launch Alternatives would be negligible.
4.15
US COAST GUARD BRIDGE PERMIT REQUIREMENTS
A bridge permit from the US Coast Guard (USCG) is required for the river crossing activity. The following
sections are required for that permit.
4.15.1
SECTION 4(F) COMPLIANCE
The USCG NEPA guidance document (Commandant Instruction M16475.1C) requires the agency to make
determinations under Section 4(f) of the DOT Act [ 49 U.S.C. 303(c)] regarding the potential impact of the
permitted activity on public recreational resources in the area. (www.uscg.mil/systems/gse/netrch2s.htm).
Potential Impacts
The proposed bridging of the Colorado River at Cibola would temporarily interfere with recreational
activities along that portion of the River. Although the BOR and BLM land used for the river crossing and
associated staging activities are not formally designated recreation areas, these activities could temporarily
hinder access to nearby designated recreational areas (BLM Oxbow Recreation Site and Cibola National
Wildlife Refuge). The BLM, Arizona Game and Fish, and other agencies have indicated that the proposed
bridge crossing site is heavily used by recreational boaters in the summertime, primarily on the weekends.
However, during mid-week, as when the proposed crossing would take place, recreational activity is
typically much less. Also, it is unlikely that the proposed river closing would affect commercial use of this
section of the River (Personal Communication, Ron Knowlton, Yuma River Tours, Yuma Arizona, 2001).
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Environmental Consequences and Mitigation
The Desert Scimitar planners worked closely with land management agencies to find a river crossing site
that would cause the least potential impact to the environment and public, while meeting the objectives of
the exercise. Consequently, it has been determined that:
1) there is no feasible and prudent alternative to the use of such land, and
2) such program includes all possible planning to minimize harm to such park, recreation area, wildlife and
waterfowl refuge, or historic site resulting from such use (per this Environmental Assessment).
Mitigation Measures
·
4.15.2
Same mitigation measures as for Section 4.12 Recreation/Visitor Services, above.
RIVER NAVIGATION
Potential Impacts
River navigation would be interrupted during the daytime rafting and bridging operation. The safety and
convenience of recreationists may be adversely affected.
Mitigation Measures
·
Marines would implement safety measures indicated in the Navigation Safety Plan and Spill Contingency
Plan (submitted to USCG as part of bridge permit application).
·
Marines would notify the public and affected agencies per mitigation measures in Section 4.12, above.
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Coordination and Contacts
5.0
COORDINATION AND CONTACTS
5.1
FEDERAL AGENCIES
U.S. BUREAU OF LAND MANAGEMENT
Natalie Guzman
Palm Springs South Coast Field Office
John Kalish
Palm Springs South Coast Field Office
Elena Misquez
Palm Springs South Coast Field Office
Wanda Raschkow
Palm Springs South Coast Field Office
Jim Foote
Palm Springs South Coast Field Office
Javier Cortozar
Palm Springs South Coast Field Office
Jim Kenna
Palm Springs South Coast Field Office
Ron Lewis
Palm Springs South Coast Field Office
Joel Schultz
Palm Springs South Coast Field Office
Don Stager
Palm Springs South Coast Field Office
Richard Wagonner
Needles Field Office
John Murray
Needles Field Office
Willow Yumiko
Needles Field Office
Margaret Hangan
El Centro Field Office
Richard Waggoner
Needles Field Office
Debbie DeBock
Yuma Field Office
Stephen Fusilier
Yuma Field Office
Gail Acheson
Yuma Field Office
Bill Alexander
Yuma Field Office
Patricia Bailey
Yuma Field Office
Jennifer Green
Yuma Field Office
Candy Holzer
Yuma Field Office
Brad Honerlaw
Yuma Field Office
Gary Roxwell
Yuma Field Office
Winfred Wong
Yuma Field Office
Thomas Zale
Yuma Field Office
Lowell Jeffcoat
Yuma Field Office
Ron Morfin
Yuma Field Office
Roger Oyler
Yuma Field Office
Karen Reichhardt
Yuma Field Office
Carol Telles
Yuma Field Office
U.S. ARMY CORPS OF ENGINEERS
Marjorie Blaine
Arizona Section, Regulatory Branch, Los Angeles District
U.S. ARMY YUMA PROVING GROUND
Lena Altamirano
Yuma Proving Ground
Vivian Blevins
Yuma Proving Ground
Frank Bornt
Yuma Proving Ground
Charles Botdorf
Yuma Proving Ground
Cynthia Ford
Yuma Proving Ground
Delores Gauna
Yuma Proving Ground
Tanya Kimber
Yuma Proving Ground
John Kruger
Yuma Proving Ground
Steve Plaisance
Yuma Proving Ground
John Schifano
Yuma Proving Ground
Steve Swain
Yuma Proving Ground
Larry Swinford
Yuma Proving Ground
Mellisa Thurmond
Yuma Proving Ground
Chuck Wullenjohn
Yuma Proving Ground
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Coordination and Contacts
U.S. BUREAU OF RECLAMATION
Kim Kirkland
Bob Adams
Chris Bates
Julian DeSantiago
Michael Igoe
Douglas Lancaster
Frank Macaluso
Ron Quamen
Russ Reichelt
Roy Romines
Paul Rose
Jeff Smith
Rick Strahan
Mike Vandevelde
Don Young
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
Yuma Area Office
U.S. COAST GUARD
David Sulouff
Bridge Office - Alameda, CA
U.S. FISH AND WILDLIFE SERVICE
Ken Corey
Carlsbad Fish and Wildlife Office
Lesley Fitzpatrick
Ecological Services - Arizona State Office
Matthew McDonald
Carlsbad Fish and Wildlife Office
Charles Sullivan
Barstow Field Office
U.S. FISH AND WILDLIFE SERVICE – CIBOLA NATIONAL WILDLIFE REFUGE
Mike Hawkes
Ciboa National Wildlife Refuge
Sharon Miller
Ciboa National Wildlife Refuge
Brenda Zaun
Ciboa National Wildlife Refuge
U.S. MARINE CORPS AIR GROUND COMBAT CENTER – TWENTYNINE PALMS
Rhys Evans
Natural Resources
U.S. MARINE CORPS, MARINE CORPS AIR STATION YUMA
Joseph Britain
MCAS - Yuma
Herbert Guillory
MCAS - Yuma
Wylie Homesley
MCAS - Yuma
Tom Manfredi
MCAS - Yuma
Ron Pearce
MCAS - Yuma
Bob Riley
MCAS - Yuma
Todd Vosper
MCAS - Yuma
Kirsten Collins
US Navy SWDIV, NAVFAC Engineering Command
Danielle Page
US Navy SWDIV, NAVFAC Engineering Command
5.2
STATE AGENCIES
ARIZONA DEPARTMENT OF ENVIRONMENTAL QUALITY
Water Permits Section
ARIZONA GAME AND FISH DEPARTMENT
Russell Engel
Region IV, Yuma
WM. Bradford Jacobson
Region IV, Yuma
William Knowles
Region IV, Yuma
Rebecca Wright
Region IV, Yuma
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Coordination and Contacts
ARIZONA STATE HISTORIC PRESERVATION OFFICE
State Historic Preservation Officer
CALIFORNIA DEPARTMENT OF BOATING & WATERWAYS
Permitting Office
CALIFORNIA DEPARTMENT OF TRANSPORTATION
Dana Weiss
Diana Baritsch
Jack Kincaid
Jimmy Straight
Terry Moore
Linda Wilford
CALIFORNIA FISH AND GAME DEPARTMENT
Chris Hays
Blythe
Kim Nichol
N. Palm Springs
CALIFORNIA HIGHWAY PATROL
Mike King
Blythe
R.W. Berg
Blythe
Jerry Thomas
Blythe
CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD
Section 401 Water Quality Permitting
CALIFORNIA STATE HISTORIC PRESERVATION OFFICE
State Historic Preservation Officer
5.3
LOCAL AGENCIES
LA PAZ COUNTY, ARIZONA
Public Works Department
IMPERIAL COUNTY, CALIFORNIA
Cheryl Fowler
Imperial County Sheriff
Darin Kune
Imperial County Sheriff
Lewis Douglas
Palo Verde County Park
RIVERSIDE COUNTY, CALIFORNIA
Keith Downs
Blythe and Desert Center Airports
Tom Turner
Blythe and Desert Center Airports
Leslie Likins
Blythe Landfill
Joe McCann
Blythe Landfill
Kathy Broadwell
Fire Department
Nick Cadena
Fire Department
Anthony Colletta
Fire Department
Skip Haverstick
Fire Department
Michael Paulette
Fire Department
Diane Wesley
Desert Center Airport
Steve Jones
Desert Center - Lake Tamarisk
CITY OF BLYTHE, CALIFORNIA
Jeff Wade
Robert Casias
Robert Grady
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Blythe Police
City of Blythe
City of Blythe
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Coordination and Contacts
Charles "Butch" Hull
Leann Martine
Jim Rodkey
Jennifer Wellman
Ruben Castillo
Tony DeBaca
Jim Harris
Pat Wolfe
City of Blythe
City of Blythe
City of Blythe
City of Blythe
Airport
Blythe Energy Action
Consultant on Master Plan
FBO Blythe Airport
PALO VERDE IRRIGATION DISTRICT, CALIFORNIA
Richard Gillmore
Ed Smith
5.4
NATIVE AMERICAN TRIBES (through YPG)
Mike Jackson, Sr., President
Pauline Jose, Acting Chairman – Cultural Committee
Stan Rice, President
Nancy Hayden, Research Director
Sherry Cordova, Chairwoman
Lisa Wanstall, Museum Director
Danielle Eddy, Jr., Chairman
Betty Cornelius, Museum Director
Delia Carlyle, Chairperson
Jon Schumaker, Tribal Archeologist
Wayne Taylor, Jr., Tribal Council
Leigh Kuwanwisiwma, Director – Cult. Preservation Office
Edward Manuel, Chairman
Joseph Joaquin, Cultural Preservation Committee
Peter Steere, Project Manager – Cultural Office
Clinton Pattea, President
Nora Helton, Chairwoman
Elda Butler, AHA MAKAV Cultural Society
Donald Antone, Governor
Barnaby Lewis, Cultural Resource Specialist
Raymond Stanley, Jr., Chairman
Vernelda Grant, Tribal Archeologist
Ivan Malik, President
Ron Chiago, Cultural Office
Vincent Randall, Chairman
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Quechan Tribal Council
Fort Yuma Indian Reservation
Yavapai-Prescott Tribe
Yavapai-Prescott Tribe
Cocopah Tribal Council
Cocopah Indian Nation
Colorado River Tribal Council
Colorado River Tribal Council
Ak Chin Community Council
Ak Chin Community
The Hopi Tribe
The Hopi Tribe
Tohono O’Odham Nation
Tohono O’odham Nation
Tohono O’odham Nation
Fort McDowell Yavapai Nation
Fort Mohave Tribal Council
Ft. Mohave Indian Reservation
Gila River Indian Community Council
Gila River Indian Community Council
San Carlos Tribal Council
San Carlos Apache Tribe
Salt River Pima-Maricopa Indian
Community Council
Salt River Pima-Maricopa Indian
Community Council
Yavapai-Apache Community Council
Environmental Assessment – March 2002
US Bureau of Land Management
List of Preparers
6.0
LIST OF PREPARERS
US BUREAU OF LAND MANAGEMENT
Natalie Guzman
Stephen Fusilier
Joel Schultz
Wanda Raschkow
Richard Waggoner
Project mgt., field survey, doc. review
Field survey, document review
Field survey, document review
Field survey, document review
Field survey, document review
US BUREAU OF RECLAMATION
Kim Kirkland
Chris Bates
Project coordination
Field survey
US FISH AND WILDLIFE SERVICE
Matt McDonald
Lesley Fitzpatrick
Charles Sullivan, III
Field survey
Field survey
Field survey
US MARINE CORPS 1ST DIVISION
LtCol John Mayer
Maj Christopher Nash
Capt Mike Callanan
Capt Joseph Lore
Planning, coordination
Project mgt., field survey
Proposed action, field survey
Proposed action, NEPA
ANTEON CORPORATION
Bruce F. Goff, PhD., Sr. Environmental Scientist
Barbara Giacomini, Sr. Archeologist
Noah Stewart, Archeologist
Matt Murray, Archeologist
Eileen Goff, Sr. Geographer
Teresa Valdovinos, Document Specialist
Scott Kerr, Sr. Environmental Analyst
Project management, technical writing
Archeology research, report prep.
Archeology research, report prep.
Archeology research, report prep.
Maps, permits, technical edit
Document management
Hazardous materials
CHARIS PROFESSIONAL SERVICES CORPORATION
Marcia Wertenberger, Esq., Regulatory Specialist
Dave Charlton, Botanist
Sonya Earll, Biologist
NEPA/CEQA, report prep.
Biology research, report prep.
Biology research, report prep.
ALICE KARL AND ASSOCIATES
Alice Karl, PhD, Sr. Biologist
Biology research, report prep.
NORTH WIND ENVIRONMENTAL, INC.
Voyko Banjac, PhD, Air Quality Engineer
Air quality analysis, report prep.
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Environmental Review
7.0
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