U.S. Department of the Interior 

National Park Service 

Death Valley National Park 

DEVILS HOLE SITE PLAN

Environmental Assessment 

July 2009 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

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U.S. Department of the Interior 

National Park Service 

Devils Hole Site Plan 

Environmental Assessment 

Death Valley National Park 

SUMMARY 

Death Valley National Park (“the Park”) proposes to make a series of improvements to the 

Devils Hole site, which contains the single remaining population of the endangered Devils Hole 

pupfish. The site is located within the Ash Meadows National Wildlife Refuge (AMNWR), but 

is managed as a detached unit of the Park. The heart of the site consists of a cavepool, the 

collapsed top of a stretch fault leading to a flooded cave system (Shepard, 2000), which contains 

the single remaining population of an endangered species, the Devils Hole pupfish (Cyprinodon 

diabolis). The pool and the rocky area immediately adjacent to it are referred to herein as “the 

Hole”. 

These improvements are intended to support maintenance and recovery of the pupfish, by: 

 Providing the species and habitat with better protection from intrusion and vandalism 

 Improving interpretive and educational opportunities for visitors 

 Enabling safe and effective scientific research and ecological monitoring, and

 Restoring the natural ecosystem processes upon which the pupfish rely

Specifically, the actions include different treatments of fence reconstruction, redesigned access 

to the visitors platform overlooking Devils Hole, design of a permanent access into the Hole, 

creation of a more stable monitoring platform, improvements to the security and communications 

systems at the site, upgrading the interpretive treatment, and habitat restoration. 

The purpose of this Environmental Assessment is to describe the affected environment and 

analyze potential impacts associated with the alternatives. 

Neither of the action alternatives considered in this EA would have impacts on prime and unique 

farmlands, environmental justice, air quality, lightscape management, waste management, land 

use, museum collections, archaeological resources, or historic structures and buildings. 

Alternative A (the Preferred Alternative)

Alternative A will have minor short-term adverse impacts on soil and water resources due to 

construction of the new fence, enclosing the visitors platform and removing the fencing below, 

creating an enclosed access trail, installation of the ships ladder, and creation of a sectional 

portable monitoring platform. It should have beneficial long-term moderate impacts to surface 

and groundwater flow due to the partial restoration of natural flows from extension of the fence 
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further towards the natural drainage, which will restore natural sediment and nutrient flows into 

the Hole. Creation of a sectional removable monitoring platform would improve the safety, 

convenience and effectiveness of ongoing monitoring operations. The security upgrades should 

help prevent and defend against intrusions, and improve the effectiveness of Park enforcement 

response against site intrusion. Overall, interpretation would be improved in a moderate way 

with the addition of a webcam and other displays at Death Valley National Park's Furnace Creek 

Visitor Center and the Ash Meadows NWR visitor center that is yet to be constructed. Visitor 

access to the viewing platform would not be restricted and would allow the casual visitor an 

opportunity to see into Devils Hole without a park ranger escort. It is not anticipated that the 

proposed site improvements will draw significant increases in visitor traffic. 

It is possible that the enhanced security presence, represented visually by the enclosed fence and 

the more intrusive Twinbar fencing, will be received negatively by visitors and affected tribes. 

The safety of researchers will be significantly improved with a permanent ladder, and 

convenience will be improved by the construction of the sectional portable monitoring platform. 

Impacts on the endangered pupfish from the enhancement of natural flows and habitat restoration 

should be beneficial, long-term and, to the extent that they ensure its survival and contribute to 

its recovery, major. Cumulative impacts to the natural resources of the site could occur with 

further water project developments that threaten the water level in the Hole, which the Park 

would likely contest if they jeopardized the pupfish. 

The Pahrump Paiute and Timbisha Shoshone tribes have strong historical and cultural ties to 

Devils Hole, and prefer that its resource conditions not be further degraded by actions that 

significantly increase physical disturbance or add to the potential for such due to increased 

visitation. The actions within Alternative A would help sustain the habitat conditions that 

support the pupfish, thereby sustaining some of the basis of its cultural appeal. The Timbisha 

Shoshone have, with some reservations, selected Alternative A as their preferred alternative. 

Alternative B

Alternative B would have minor short-term adverse impacts on soil and water resources due to 

construction of the new fence, erection of permanent handrails down the cliffside, building the 

railed access trail, and removal of fencing under the visitors platform. It should have beneficial 

long-term moderate impacts to surface and groundwater flow due to the restoration of natural 

flows from extension of the fence to encompass the natural drainage, which will restore natural 

sediment and nutrient flows into the Hole. The installation of a fixed monitoring platform bolted 

directly into the eastern cliffside would enhance safety and convenience for researchers 

monitoring the Hole, though the construction would pose greater risk of rock and sediment 

deposition directly into the Hole. The security upgrades should help prevent and defend against 

intrusions, and improve the effectiveness of Park enforcement against site intrusion. Overall, 

interpretation would be improved in a moderate way with the addition of a webcam and other 

displays at Death Valley National Park's Furnace Creek Visitor Center and the Ash Meadows 

NWR visitor center that is yet to be constructed. Visitor access to the viewing platform would be 

restricted and only allowed as part of a park led tour of the site. It is not anticipated that the 

proposed site improvements will draw significant increases in visitor traffic. 
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It is possible that the enhanced security presence, represented visually by the enclosed fence and 

the more intrusive Twinbar fencing, will be received negatively. The limiting of access to 

supervised tours only would provide enhanced interpretation to visitors, but it could be perceived 

negatively by the public because of limited access. The safety of researchers will be somewhat 

improved with a permanent handrail. Impacts on the endangered pupfish from the enhancement 

of natural flows and habitat restoration should be beneficial, long-term and, to the extent that 

they ensure its survival and contribute to its recovery, major. Cumulative impacts to the natural 

resources of the site could occur with further water project developments, which the Park would 

likely contest if they jeopardized the pupfish. 

The actions within Alternative B would help sustain the habitat conditions that support the 

pupfish, thereby sustaining some of the basis of its cultural appeal. The Timbisha Shoshone 

have indicated that they prefer Alternative A over Alternative B. It is not anticipated that the 

proposed site improvements will draw significant increases in visitor traffic. 

A note on comments

Comments on this Environmental Assessment (EA) may be submitted during the 30-day open 

comment period via the national planning web site at http://parkplanning.nps.gov. Comments 

must be postmarked or transmitted no later than 5 p.m. on September 18, 2009. 

For people wishing to submit comments on this EA: Before including your address, phone 

number, email address, or other personal identifying information in your comment, be aware that 

your entire comment – including your personal identifying information – may be made public. 

While you can ask us to withhold your personal identifying information from public review, we 

cannot guarantee that we would be able to do so. We would always make submissions from 

organizations or businesses, and from individuals identifying themselves as representatives of 

officials of organizations or businesses, available for public inspection in their entirety. 

Written comments may be also sent by regular mail to: 

Mike Bower 

Fish Biologist 

Death Valley National Park 

1321 So. Highway 160, Suite 1 

Pahrump, NV 89048 

775-537-0787 phone 

775-537-6380 fax 

Mike_R_Bower@nps.gov 

Mention of trade names or commercial products by the U.S. Department of the Interior National 

Park Service does not constitute endorsement or recommendation for use. As the nation's 

principal conservation agency, the Department of the Interior has responsibility for most of our 

nationally owned public lands and natural and cultural resources. This includes fostering the 

wisest use of our land and water resources, protecting our fish and wildlife, preserving the 

environmental and cultural values of our national parks and historical places, and providing for 
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enjoyment of life through outdoor recreation. The department assesses our energy and mineral 

resources and works to assure that their development is in the best interests of all. The 

department also has a major responsibility for American Indian reservation communities and for 

people who live in island territories under U.S. administration. 

July 2009 

 
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TABLE OF CONTENTS

SUMMARY ................................................................................................................................... ii

TABLE OF CONTENTS ............................................................................................................ vi

List of Tables ............................................................................................................................ vii

List of Figures ........................................................................................................................... vii

ACRONYMS AND ABBREVIATIONS .................................................................................. viii

1.0 INTRODUCTION.............................................................................................................. 1

1.1 PURPOSE AND NEED FOR ACTION ................................................................................... 1

1.2 PARK PURPOSE AND SIGNIFICANCE ................................................................................ 3

1.3 DEVILS HOLE SIGNIFICANCE .......................................................................................... 4

1.4 PROJECT BACKGROUND .................................................................................................. 4

1.5 RELATIONSHIP OF THE PROPOSED ACTION TO PREVIOUS PLANNING EFFORTS ........... 5

1.6 SCOPING ........................................................................................................................... 6

1.7 THE ENVIRONMENTAL ASSESSMENT .............................................................................. 7

1.8 ISSUES ............................................................................................................................... 7

1.9 IMPACT TOPICS ................................................................................................................ 8

1.9.1 Impact Topics Analyzed in this Environmental Assessment .............................. 8

1.9.2 Impact Topics Dismissed from Further Consideration ..................................... 11

2.0 ALTERNATIVES CONSIDERED ................................................................................ 16

2.1 NO ACTION ALTERNATIVE ............................................................................................ 16

2.2 ALTERNATIVES ANALYZED IN THIS EA ....................................................................... 16

2.2.1 ALTERNATIVE A (THE PREFERRED ALTERNATIVE) ............................................. 16

2.2.2 ALTERNATIVE B ..................................................................................................... 22

2.3 ALTERNATIVES CONSIDERED BUT DISMISSED ............................................................. 27

2.4 ENVIRONMENTALLY PREFERRED ALTERNATIVE ......................................................... 29

2.5 PREFERRED ALTERNATIVE ........................................................................................... 31

2.6 MITIGATION MEASURES ............................................................................................... 32

2.7 COMPARISON OF ALTERNATIVES .................................................................................. 35

3.0 AFFECTED ENVIRONMENT ...................................................................................... 41

3.1 SOILS AND GEOLOGY ..................................................................................................... 41

3.2 WATER RESOURCES ...................................................................................................... 41

3.2.1 Groundwater & Hydrogeology ............................................................................ 41

3.2.2 Surface Water ........................................................................................................ 44

3.3 VEGETATION .................................................................................................................. 45

3.4 WILDLIFE ....................................................................................................................... 45

3.5 THREATENED & ENDANGERED SPECIES, CANDIDATE SPECIES, AND SPECIES OF 

SPECIAL CONCERN ................................................................................................................... 46

3.6 VISITOR USE AND EXPERIENCE ..................................................................................... 50

3.7 PARK OPERATIONS ........................................................................................................ 51

3.7.1 Security .................................................................................................................. 51

3.7.2 Scientific Research and Monitoring .................................................................... 51

3.8 CULTURAL RESOURCES ................................................................................................. 55

4.0 ENVIRONMENTAL CONSEQUENCES ..................................................................... 58

4.1 METHODOLOGY ............................................................................................................. 58
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4.1.1 Soils and Geology .................................................................................................. 62

4.1.2 Water ...................................................................................................................... 63

4.1.3 Vegetation .............................................................................................................. 64

4.1.4 Wildlife ................................................................................................................... 65

4.1.5 Threatened & Endangered Species, Candidate Species, and Species of Special 

Concern ................................................................................................................................ 66

4.1.6 Visitor Experience ................................................................................................. 67

4.1.7 Park Operations .................................................................................................... 68

4.1.8 Cultural Resources................................................................................................ 68

4.2 ANALYSIS OF ALTERNATIVES ........................................................................................ 70

4.2.1 No Action Alternative ........................................................................................... 70

4.2.2 Alternative A ......................................................................................................... 80

4.2.3 Alternative B ........................................................................................................ 111

5.0 CONSULTATION AND COORDINATION .............................................................. 140

5.1 PUBLIC INVOLVEMENT ................................................................................................ 140

5.2 CONSULTATION ............................................................................................................ 140

5.3 PREPARERS AND CONTRIBUTORS ................................................................................ 141

5.4 DISTRIBUTION LIST FOR ENVIRONMENTAL ASSESSMENT ......................................... 142

6.0 REFERENCES ............................................................................................................... 145

7.0 GLOSSARY.................................................................................................................... 150

APPENDIX A: PROJECT COMPONENT DESIGNS ........................................................ A-1

APPENDIX B: AGENCY CONSULTATIONS .................................................................... B-1

APPENDIX C: SPECIES OF CONCERN IN ASH MEADOWS NWR ............................ C-1

APPENDIX D: DEVILS HOLE PLANT SPECIES ............................................................. D-1

List of Tables 

Table 2-1. Comparison of Alternatives ........................................................................................ 35

Table 2-2. Impact Comparison of Alternatives ............................................................................ 37

Table 3-1. Special Status Species Categories .............................................................................. 46

List of Figures 

Figure 1.1. Devils Hole Site within Ash Meadows NWR ............................................................. 2

Figure 2.1. Alternative A (Preferred Alternative) ........................................................................ 17

Figure 2.2. Alternative B ............................................................................................................. 23

Figure 3-1. Sectional View of Devils Hole .................................................................................. 48

Figure 3-2. Ladder Access to the Site (Ladder in yellow circle) ................................................. 52

Figure 3-3. Descent from Ladder Landing to Pool ...................................................................... 52

Figure 3-4. Divers Entering Devils Hole ..................................................................................... 53
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ACRONYMS AND ABBREVIATIONS 

AMNWR Ash Meadows National Wildlife Refuge 

BMPs Best Management Practices 

CEQ Council on Environmental Quality 

CFR Code of Federal Regulations 

Cfs Cubic Feet per Second 

CWA Clean Water Act 

Cy Cubic yards 

DO NPS Director’s Order 

EA Environmental Assessment 

FPPA Farmland Protection Policy Act 

FHA Federal Highways Administration 

GMP General Management Plan 

Mya Million years ago 

NDOW Nevada Department of Wildlife 

NEPA National Environmental Policy Act 

NHPA National Historic Preservation Act 

NPS National Park Service 

NRHP National Register of Historic Places 

RMP Resource Management Plan 

SHPO State Historic Preservation Office 

SR State Road 

SNWA Southern Nevada Water Authority 

T&E Threatened and Endangered 

THPO Tribal Historic Preservation Office 

USACE United States Army Corps of Engineers 

USC United States Code 

USEPA United States Environmental Protection Agency 

USFWS United States Fish and Wildlife Service 
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1.0 INTRODUCTION 

1.1 PURPOSE AND NEED FOR ACTION

Devils Hole is a 40-acre site located on lands within the Ash Meadows National Wildlife Refuge 

(AMNWR) but managed as a detached unit of Death Valley National Park (“the Park”). At the 

heart of the site lies a cavepool, the collapsed top of a stretch fault leading to a flooded cave 

system (Shepard, 2000), which contains the single remaining population of an endangered 

species, the Devils Hole pupfish (Cyprinodon diabolis). See Figure 1-1. The Park manages the 

ongoing recovery actions for the species in collaboration with the U.S. Fish & Wildlife Service 

(USFWS) and Nevada Department of Wildlife (NDOW), and attempts to secure and enhance the 

remaining population while building public support for protection of the habitat features on 

which the species relies—in particular, maintaining the groundwater table at sufficiently high 

depth below ground to allow for normal feeding, breeding, and spawning activities of the fish. 

The purpose of the proposed action is to redesign the man-made features of the Devils Hole site 

in a way that does no permanent harm to the species or its habitat, and achieves the following 

goals: 

 Provide the species and habitat with better protection from intrusion and vandalism 

 Improve interpretive and educational opportunities for visitors 

 Enable safe and effective scientific research and ecological monitoring

 Restore the natural ecosystem processes upon which the pupfish rely

The need for the proposed action is based primarily on the fragility and long-term decline of the 

Devils Hole pupfish, composed as it is of a single small population. An April 2006 population 

survey counted 38 individuals, the lowest on record, furthering a trend of decline from previous 

years. The most recent count in April of 2009 was 70 (±13.5 SE), likely representing an increase 

over recent spring surveys. The fragility of the population is due to a combination of several 

factors, many of which are inherent to the Devils Hole site. Specifically, the Devils Hole pupfish 

is vulnerable to changes in its habitat as it is restricted to a single water-filled cavern. Unlike 

most other fishes, the Devils Hole pupfish has no ability to migrate to fulfill its life history 

requirements or seek optimal habitats. If the habitat of Devils Hole changes to become less 

suitable, the Devils Hole pupfish population is likely to decline as a consequence. 

Threats to habitat suitability for the Devils Hole pupfish could include a variety of anthropogenic 

factors such as global warming, airborne dust from nearby roads, accidents by researchers, 

intentional vandalism, accidental introduction of invasive species, habitat alteration by site 

infrastructure, or groundwater development and resulting water level declines. It is hoped that 

by enabling scientific research and monitoring, the causes of the recent decline in abundance of 

the Devils Hole pupfish can be better understood, hopefully preventing such declines in the 

future. 

The project purpose described above also includes improvements to the visitor interpretive 

experience. As an ecologically unique site, and because of the presence of the lone remaining 

population of the endangered pupfish, Devils Hole has been recognized as deserving of federal 

protection. This protection involves a limitation on groundwater pumping throughout Ash 
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Meadows and further into the Amargosa Valley. As development pressures continue to move 

west from Las Vegas, it becomes increasingly important to maintain public support for such 

limitations on development through education and interpretation of the area’s ecological 

resources and processes. This forms the basis of need for the enhancements to the interpretive 

experience embedded in the project purpose. 

Figure 1.1. Devils Hole Site within Ash Meadows NWR 
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1.2 PARK PURPOSE AND SIGNIFICANCE

The purpose and significance of Death Valley National Park are defined in the Final General 

Management Plan (NPS, 2002). According to this document, which is based on the park’s 

enabling legislation and Presidential Proclamations, the purposes of Death Valley National Park 

include: 

 To preserve the unrivaled scenic, geologic, and natural resources of these unique natural 

landscapes, while perpetuating significant and diverse ecosystems of the California desert 

in their natural state, and to ensure the maximum protection of wilderness values 

provided by law. 

 To preserve the cultural resources of the California desert associated with prehistoric, 

historic and contemporary Native American culture, patterns of western exploration, 

settlement and mining endeavors. 

 Provide opportunities for compatible public outdoor recreation and promote the public’s 

understanding and appreciation of the California desert by interpreting the natural and 

cultural resources. 

 Retain and enhance opportunities for scientific research in undisturbed ecosystems. 

Some features of the park that contribute to its significance include the following: 

 Death Valley National Park contains the lowest point in North America at 282’ below sea 

level. The valley floor receives the least precipitation in the United States (averaging 

1.84 inches per year) and has the nation’s highest recorded temperature (1340 F). 

 The Park is world renowned for its exposed, complex and diverse geology and tectonics. 

 Death Valley has been the continuous home of Native Americans, from prehistoric 

cultures to the present-day Timbisha Shoshone Tribe. 

 Death Valley contains one of the nation’s most diverse and significant fossil records and 

most continuous volcanic histories. 

 Ninety-five percent of the Park is designated wilderness, providing unique opportunities 

for quiet, solitude, and primitive adventure in an extreme desert ecosystem. 

 The Park’s natural resources are extremely diverse. The area preserves large expanses of 

creosote bush valleys and other vegetation typical of the Mojave Desert. Extreme 

conditions and isolation provide habitat for an unusually high number of plant and animal 

species that are highly adapted to these conditions (of which the Devils Hole pupfish is a 

prime example). 
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1.3 DEVILS HOLE SIGNIFICANCE 

Devils Hole is administered by the Park but located within a larger spring complex in Nevada 

that is part of the Ash Meadows National Wildlife Refuge. A limestone cave at Devils Hole is 

the only natural habitat of the Devils Hole pupfish, listed as endangered by the U.S. government 

and the State of Nevada. The cavepool at Devils Hole is essentially the “skylight” to the aquifer 

which feeds it. The aquifer itself is regionally significant - it is the source of water for other 

springs in the Ash Meadows area as well as on the eastern side of Death Valley--and the aquifer 

also determines the cave’s water level. The feeding and spawning of the pupfish depend on the 

existence of a shallow (but submerged) limestone shelf within the 90-degree waters of the 

cavepool at Devils Hole. 

In 1952, the forty acres surrounding Devils Hole was set aside as part of the Death Valley 

National Monument, for the purpose of protecting the Devils Hole pupfish. Despite this 

protection, in the late 1960s well-drilling for groundwater caused a decline of the Devils Hole 

pupfish population, driving litigation which eventually resulted in a historic water rights 

decision: the U. S. Supreme Court in 1976 determined that the National Park Service had a 

reserved water right to a certain level of groundwater at Devils Hole (Cappaert v. United States, 

1976), and stopped well drilling that affected the site. The purpose of the reserved water right is 

to maintain the water level in Devils Hole to assure the survival of the Devils Hole pupfish. This 

reserved water right affects 21,760 acres of essential habitat for the pupfish surrounding Devils 

Hole, where groundwater removal would cause the greatest impact on the Hole (NPS, 2002). 

These acres are within an area much coveted by private developers in the fast growing corridor 

west of Las Vegas. 

In 1984, the Ash Meadows National Wildlife Refuge was created to conform quite closely with 

this area of groundwater impact, largely for the purpose of further ensuring protection of the 

spring-fed wetlands and groundwater network that support the Devils Hole ecosystem. It is 

located approximately 90 miles northwest of Las Vegas in the Amargosa Valley of southern Nye 

County, Nevada. Devils Hole is surrounded on three sides by AMNWR; on the north side it 

abuts Bureau of Land Management land (Ash Meadows, 2007). 

1.4 PROJECT BACKGROUND

Actions to improve the access, security and safety of the Devils Hole site have been 

contemplated since at least 2002, due to periodic episodes of vandalism at the site and the 

deteriorating safety and security conditions for researchers, who monitor habitat conditions at the 

site on a continuing basis. While some of the actions have progressed to the design stage, none 

has ever been evaluated in an Environmental Assessment. 

Previous plans have included: 

 A new design for the scientific monitoring platform, which is used by researchers for 

various scientific measurements. In the new design, the platform would fold down 

mechanically when needed, from a vertical storage position along the cliffside, and rest 

just above the cave pool, thereby making it safer and more convenient than the current 

situation. 
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 Installing additional cameras and communications equipment on the existing 

communications tower, to enable remote communications between the Park’s Law 

Enforcement personnel and the site. 

 New fence design, placement and configuration, to improve intrusion protection and to 

enable a more natural flow of sediments into the hole (the current gate impedes the 

natural flow of larger materials). 

 General concepts to improve the interpretive treatment at the site, while still enhancing its 

security. 

1.5 RELATIONSHIP OF THE PROPOSED ACTION TO PREVIOUS PLANNING 

EFFORTS

Several plans, projects, and standards that the National Park Service and Death Valley National 

Park either have in place or have in progress may affect decisions regarding the Devils Hole Site 

Plan project. In addition, the site’s location within AMNWR requires planning and coordination 

with U.S. Fish & Wildlife Service for any actions that could impact Refuge resources. 

The General Management Plan (NPS, 2002) established the guiding management philosophy for 

the Park and provides strategies for addressing issues and achieving management objectives. 

The emphasis of the GMP is protection and preservation of natural and cultural resources. 

 The GMP established water resource objectives that include the goal of maintaining the 

water levels at Devils Hole. This project complies with the GMP by attempting to restore 

and protect the natural conditions and processes that keep the water table at its required 

level. 

 The GMP also mandates biannual fish counts. This project is intended to make the fish 

counting process safer for scientific staff by upgrading the ladder access to the pool. 

 The GMP calls for continued protection of the water right established by the U.S. 

Supreme Court for the protection of the pupfish. The security improvements included in 

the proposed action are intended to secure this protection.

The Devils Hole pupfish recovery plan (USFWS, 1990) states recovery criteria which, when met, 

will enable the Devils Hole pupfish to be downlisted to threatened (a species with a single 

natural population cannot be delisted (USFWS, 2007)). These recovery criteria include a 

minimum water level of 1.4 feet below a copper washer installed along the cave cliff in 1976, a 

population of 300 individuals during winter and 700 during late fall, and two refugia populations 

established offsite from the Hole. This project attempts to make monitoring easier and safer for 

Park researchers towards those ends, and to restore and improve the natural flow of sediment, 

nutrients and surface water into the Hole. 

AMNWR is in the planning stages on several projects that could impact Devils Hole: 

• AMNWR faces numerous transportation challenges, including managing the access points to 

the Refuge and the use of existing routes. The Desert Refuge complex has undertaken a 

transportation survey that will provide recommendations for improvements to the existing 

network of roads and parking lots and address transportation, management, maintenance, and 
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coordination threats and challenges faced by the Refuge (Ash Meadows, 2007). The goal of 

these improvements is to enhance visitor safety and to support the resource protection 

mission and policies of the NWR. 

• The Refuge also faces substantial issues related to existing hydrologic and geologic 

challenges in terms of planning and maintaining a road network. The high water table and 

presence of springs near or under roadways cause significant damage to roads and often 

make segments impassable. Roadway maintenance and planning must be conducted in close 

coordination with other ongoing efforts that will affect water flow and water location within 

the Refuge, including sub-basin restoration and modifications to existing dams. 

• The Desert NWR Complex is preparing a Comprehensive Conservation Plan/Environmental 

Impact Statement (CCP/EIS) that includes four refuges: Desert, Ash Meadows, Pahranagat 

and Moapa. The CCP/EIS describes the resources, public use, goals, objectives, and 

strategies for AMNWR and for the other refuges. It also identifies potential environmental 

effects of potential actions under consideration. The CCP/EIS effort was started in 2004; the 

administrative draft has been completed; and the final draft is currently being prepared. The 

goals of the CCP/EIS are very broad, with supplemental studies called step-down plans being 

developed to recommend more specific measures that implement CCP/EIS policies. 

1.6 SCOPING

Scoping is an open process to determine the breadth of environmental issues and alternatives to 

be addressed in an EA. Scoping involves obtaining internal and external input on project-related 

issues from resource specialists and the public, respectively. The Park conducted internal 

scoping with appropriate NPS, Nevada Department of Wildlife (NDOW), and USFWS staff and 

external scoping with the public, including interested and affected groups or individuals and nonNPS agency personnel. 

An interdisciplinary team comprising Park, NDOW, and USFWS staff members contributed to 

the internal scoping process. This process resulted in definition of the purpose and need, 

identification of potential actions to address the need, determination of what the likely issues and 

impact topics would be, and identification of the relationship, if any, of the Proposed Action to 

other planning efforts in the Park. 

For external scoping, a public scoping letter describing the Proposed Action and requesting 

public input on the proposal was issued to private parties; State, Federal, and local agencies in 

November, 2007. Two public meetings were held, which drew a total of five participants. The 

main issues raised by commenters were: (1) the importance of communicating the pupfish 

“story” and its significance to the public, while (2) minimizing the actual disturbance to the 

habitat itself that could be caused by attracting more visitors. The Park staff gathered specific 

suggestions for how off-site interpretation could be enhanced towards meeting both goals 

simultaneously. The external scoping period ended on December 26, 2007. 
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Discussions have begun with members of the Timbisha Shoshone and Pahrump Piute tribes, 

pursuant to §106 of the National Historic Preservation Act, as amended in 1992 (16 USC 470 et 

seq.; NHPA). These are further described in Section 5.2.

1.7 THE ENVIRONMENTAL ASSESSMENT

This environmental assessment (EA) analyzes the environmental impacts that would result from 

the alternatives considered, including the No Action alternative. This EA has been prepared in 

accordance with the National Environmental Policy Act (NEPA) of 1969 (42 United States Code 

(USC) 4321 et seq.), the Council on Environmental Quality (CEQ) regulations (40 Code of 

Federal Regulations (CFR) 1500 through 1508) for implementing NEPA, and the NPS NEPA 

compliance guidance handbook (DO-12, Conservation Planning, Environmental Impact 

Analysis, and Decision-making). 

1.8 ISSUES

Issues and concerns affecting the Proposed Action were identified by specialists at Death Valley 

National Park, NDOW, USFWS and input from the public and Federal agencies. External and 

internal scoping meetings and analysis of previous projects, plans and design concepts were 

conducted to identify and explore concerns that have led to the current planning stage. The 

following issues shaped the development of alternatives and the consideration of impacts: 

 The interpretive experience—Limited on-site interpretation has failed to create the level 

of public education necessary to support the resource-intensive protection efforts for the 

Devils Hole pupfish. 

 Researcher safety—The current mode of staff access to the cavepool and construction of 

the makeshift monitoring platform are “an accident waiting to happen”, thereby risking 

the safety of Park Service employees. 

 Hindrance of natural flow—The location of the current fence, inside the perimeter of the 

drainage wash down the hillside into the Hole, somewhat impedes the natural flow of 

sediment and organic materials into the cavepool, although structural measures (such as 

raising the bottom of the fencegate) have been taken to allow as much material as 

possible to flow through. 

 Shading of the water surface—The current viewing platform casts some shadows on the 

water surface of the pool, thereby restricting direct sunlight and impacting primary 

productivity in the Hole. The monitoring equipment also casts shadows to a lesser extent. 

Any new location or configuration of the visitors platform and monitoring equipment 

should create no more impact, and preferably less, on direct sunlight. 

 Security from intrusion—There have been periodic episodes of vandalism and intrusion 

at the site, which could lead to harm to the pupfish directly (apparent attempts to capture 

fish) or to the pool (apparent attempts to dump foreign matter). These intrusions also cost 

law enforcement resources to respond to alarms and to restore damaged fencing. Other 

considerations that result from the need for improved security are the demand for 

enhanced power and enhanced data communications, both of which could create more 

environmental impacts as the infrastructure is built. 
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Death Valley National Park Devils Hole Site Plan 

Purpose and Need 8 

 Monitoring—Beyond the safety issue, the inconvenience of having to construct the 

monitoring platform at each monitoring visit costs researchers time, by requiring multiple 

staff members for each site visit. 

1.9 IMPACT TOPICS

Impact topics are the resources of concern that could be affected by the range of alternatives. 

Specific impact topics were developed to ensure that alternatives were compared on the basis of 

the most relevant topics. The following impact topics were identified on the basis of Federal 

laws, regulations, and executive orders; NPS Management Policies 2006, and NPS knowledge of 

limited or easily impacted resources. A brief rationale for the selection of each impact topic is 

given below, as well as the rationale for dismissing specific topics from further consideration. 

1.9.1 Impact Topics Analyzed in this Environmental Assessment 

Soils and Geology

Construction activities, such as excavation and the use of heavy equipment, would disturb soils 

and potentially cause soil compaction and erosion in the project area, and increase sediment 

deposition into the Hole. Site preparation and construction of platforms and related project 

components would require excavation and subsequent disposal of rock and fill material. 

Therefore, soils and geology are addressed as an impact topic in this EA. 

Water Resources

A primary constituent element for survival of the Devils Hole pupfish is an adequate water level 

in the cave pool. A second is a natural flow of nutrients and organic material into the Hole, 

which means that water quality must be protected. A third is water temperature. Devils Hole is 

dependent on the health of the spring-fed aquifer network that flows within the AMNWR--the 

so-called Ash Meadows flow system (Riggs & Deacon, 2004). Any project in the impact area 

must be evaluated for its effects on the water level and water quality in the cavepool itself and 

the groundwater resources that feed it. 

In addition, NPS Management Policies 2006 require protection of water quality consistent with 

the provisions of the Clean Water Act of 1977, a national policy to restore and maintain the 

chemical, physical, and biological integrity of the nation’s waters and to prevent, control, and 

abate water pollution. Section 404 of the Clean Water Act authorizes the U.S. Army Corps of 

Engineers (USACE) to prohibit or regulate, through a permitting process, the discharge of 

dredged or fill material into U.S. waters. Executive Order 11990, Protection of Wetlands, NPS 

Management Policies 2006, Section 4.6.5, Wetlands, and NPS DO #77-1, Wetland Protection, 

require an examination of impacts to and protection of wetlands. 

Construction activities have the potential to affect water quality in the project area. In the short 

term, construction activities will compact and/or erode soil and could increase sediment flows 

into the sensitive Hole ecosystem. In the long run, the project is intended to have a beneficial 

impact on water quality by helping maintain the natural chemical, biological and energy balance 
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Death Valley National Park Devils Hole Site Plan 

Purpose and Need 9 

of the ecosystem. Therefore, water resources, particularly ground and surface water flows, are 

discussed in detail in this EA. 

Biotic Communities—Vegetation & Wildlife

Biotic communities would be disturbed by construction activities. They would also be impacted 

by relocation or removal of the visitors platform and gate that currently impede some sediment 

flow. Therefore, biotic communities will be addressed as an impact topic in this EA. 

Threatened, Endangered, and Candidate Species and Species of Special Concern

The Endangered Species Act (ESA), 16 USC 1531 et seq., establishes a national program for the 

conservation of threatened and endangered species of fish, wildlife, and plants, as well as the 

preservation of the ecosystems on which they depend. ESA Section 7 requires any federal 

agency authorizing, funding, or carrying out any action to ensure that the action is not likely to 

jeopardize the continued existence of any endangered species or threatened species, or result in 

the destruction or adverse modification of critical habitat of such species. Because the key 

purpose of the action is to enhance the survival of the endangered Devils Hole pupfish, T&E 

species will be addressed as an impact topic in this EA. The consultation letter from the Park to 

U.S. Fish & Wildlife Service is included in Appendix B. 

Visitor Use and Experience

The alternatives under consideration in this EA would preclude visitor use of the Devils Hole site 

itself during at least some portions of construction activities, although because the site is isolated 

from other visitor destinations within the Park and the Ash Meadow Refuge, construction would 

not affect the visitor experience of the main Park and of the Refuge overall. On an ongoing 

basis, the proposed action is by its very purpose intended to enhance the visitor’s experience of 

Devils Hole. Therefore, visitor use and experience, including effects from changes in visual and 

interpretive treatments, will be addressed as an impact topic in this EA. 

Park Operations

Project implementation would benefit park operations in the project area by reducing the number 

and improving the efficiency of ranger patrols and emergency responses, through the use of 

improved detection and data communications. It would further benefit park operations by 

improving the safety of monitoring and research activities for Park staff and other scientists who 

conduct scientific experiments at the Hole. Therefore, these two aspects of park operations will 

be addressed as impact topics in this EA. 

Ethnographic Resources

Archeological evidence shows that the Devils Hole area has been occupied for at least 9,000 

years, and the Southern Paiute and Timbisha Shoshone tribes still inhabit the surrounding area 

today. In 1994, Congress enacted the California Desert Protection Act, P.L. 103-433, including 

section 705 (b), which preliminarily addressed the need of the Timbisha Tribe for a recognized 

land base. It was followed in 2000 by the Timbisha Homeland Act, which established a 7000-
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Purpose and Need 10 

acre land base for the Timbisha Shoshone Tribe within its ancestral homelands. Approximately 

three hundred acres of this homeland lie within the Park, and the remaining acres are located 

around the homeland in southern Nevada and California. The Timbisha have a land base of 

1,000 acres at Death Valley Junction (NPS, 2002d:94). Devils Hole is approximately 10 miles 

from the closest Timbisha land base. The Pahrump Paiute are a non-federally recognized group, 

with members living in the Pahrump and Las Vegas area. 

Devils Hole is believed to fit the definition of a Traditional cultural property, owing to its long 

history with the Timbisha Shoshone and Pahrump Paiute tribes. As such, the Park will undertake 

consultations with these tribes on the effects of the proposed action pursuant to Section 106 of 

the National Historic Preservation Act (further detailed in Section 5.2). The tribes are also 

allowed access to the property under the American Indian Religious Freedom Act of 1978. 

Therefore, the impact of the alternatives on the cultural values that make Devils Hole a 

Traditional cultural property will be discussed in this EA. 

A variety of laws and policies apply to the protection of cultural resources at Park Service units: 

National Historic Preservation Act 

The National Historic Preservation Act (NHPA), 16 USC § 470 et seq., requires NPS to consult 

with the California State Historic Preservation officer (SHPO) prior to any construction to ensure 

that no historical properties will be adversely affected by a proposed project. NPS must also 

afford the Advisory Council on Historic Preservation a reasonable opportunity to comment on 

the proposed project. Regulations for implementing NHPA are found in 36 CFR 800-812. 

Archaeological Resources Protection Act 

The Archaeological Resources Protection Act, 16 USC § 470aa et seq., requires a permit for 

excavation or removal of archaeological resources from publicly held or Native American lands. 

The Act requires that excavations further archaeological knowledge in the public interest, and 

that the resources removed remain the property of the United States. Regulations for 

implementing the Act are found in 43 CFR 7 and 36 CFR 296. 

American Indian Religious Freedom Act 

The American Indian Religious Freedom Act, 42 USC § 1996, establishes policy to protect and 

preserve the inherent and Constitutional right of Native Americans to believe, express, and 

exercise their traditional religions. The law ensures the protection of sacred locations, access of 

Native Americans to those sacred locations and traditional resources that are integral to the 

practice of their religions, and establishes requirements that would apply to Native American 

sacred locations, traditional resources, or traditional religious practices potentially affected by 

construction and operation of proposed facilities. Regulations for implementing the Act are also 

found in 43 CFR 7. 
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Native American Graves Protection and Repatriation Act 

The Native American Graves Protection and Repatriation Act, 25 USC § 3001, directs the 

Secretary of the Interior to guide the repatriation of federal archaeological collections and 

collections that are culturally affiliated with Native American tribes and held by museums that 

receive federal funding. NPS would follow the provisions of this Act if any excavations 

associated with the proposed construction led to unexpected discoveries of Native American 

graves or grave artifacts. Regulations for implementing the Act are found in 43 CFR 10. 

1.9.2 Impact Topics Dismissed from Further Consideration 

Traffic and Transportation

The Proposed Action does not involve changes to the roads that access Devils Hole. It is 

anticipated that any changes made for the visitor experience as well as for staff convenience 

would not require any reconfiguration of existing roads. For this reason, transportation is not 

addressed as an impact topic in this EA. 

Prime and Unique Farmlands

In August 1980, the CEQ directed that Federal agencies assess the effects of their actions on 

farmland soils classified by the U.S. Department of Agriculture's Natural Resources 

Conservation Service as prime or unique. Prime or unique farmland is defined as soil that 

particularly produces general crops, such as common foods, forage, fiber, and oil seed; unique 

farmland produces specialty crops, such as fruits, vegetables, and nuts. Although agricultural 

irrigation has previously threatened the water level on which the Devils Hole pupfish depends, 

there are no prime or unique farmlands in the project area, and none would be reached by the 

proposed action. Therefore, the topic of prime and unique farmlands was dismissed as an impact 

topic in this EA. 

Visitor Safety

Neither the Proposed Action nor any of the alternatives would have any impact on visitor safety. 

Access to Devils Hole would continue to be in maintained pathways, and any interaction with the 

steep inclines directly surrounding the site would be prevented with improved fencing. 

Therefore, visitor safety was dismissed as an impact topic in this EA. 

Air Quality

Devils Hole is in the Nye County attainment area of Nevada, which is in attainment on all 

National Ambient Air Quality Standards pollutants, with the exception of the Pahrump Valley, 

almost 20 miles southeast, which has been designated non-attainment for particulate matter 

(PM10) and is operating under a Memorandum of Understanding with USEPA. Air quality at 

Devils Hole could be impacted during the construction phase of the project; however, impacts 

would be temporary and minor in intensity. Overall, there would be a slight and temporary 

degradation of local air quality due to dust generated by activities and emissions from 

construction equipment. These effects would last only during construction activities. Best 
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Purpose and Need 12 

Management Practices (BMPs) would be utilized to limit dust generation and dispersal. To keep 

equipment emissions down, equipment would be properly maintained. The Refuge’s air quality 

would not be affected by this action. Therefore, air quality was dismissed as an impact topic in 

this document. 

Archaeological Resources

The National Park Service is required to, “preserve collections of prehistoric and historic 

material remains, and associated records, recovered under the authority of the Antiquities Act 

(16 U.S.C. 431-433), the Reservoir Salvage Act (16 U.S.C. 469-469c), section 110 of the 

National Historic Preservation Act (16 U.S.C. 470h-2), or the Archaeological Resources 

Protection Act (16 U.S.C. 470aa-mm)” (36 CFR Part 79). These regulations, promulgated under 

the authority of the Secretary of the Interior, apply to findings made by historic preservation 

professionals that meet qualification standards for Federal projects. 

An archaeological survey was conducted on 30 of the 40 acres of the Devils Hole site. Eleven 

isolated finds were found during the survey, most of which were historic or modern. These 

include a prehistoric flake, a trail segment, NPS boundary rock cairns, a prospect, and a glass 

scatter. The date of the prehistoric flake is unknown, but is probably over 100 years old. The 

historic finds appear to mostly date to the time that the NPS took over management of the site, 

though the prospect pit is probably older. As all of the remains found during the survey were 

isolated finds, they are not eligible for nomination to the National Register of Historic Places. 

The undertaking is occurring in an area with no sites, and therefore it is not expected to have an 

effect on archeological resources. Therefore, archeological resources were dismissed as an 

impact topic in this document. 

Historic Structures/Buildings

The National Historic Preservation Act (NHPA), as amended in 1992 (16 USC 470 et seq.); 

NEPA of 1969 (42 USC 4321 et seq.); NPS DO #28, Cultural Resource Management Guideline 

(1998a), NPS Management Policies 2006, and NPS DO #12, Conservation Planning, 

Environmental Impact Analysis, and Decision Making (2001b) require the consideration of 

impacts on historic structures and buildings listed in or eligible for listing in the National 

Register of Historic Places. Because there are no structures that would be affected by the 

project, Historic Structures/ Buildings was dismissed as an impact topic in this EA. 

Cultural Landscapes

Cultural landscapes are defined by the NPS as “a reflection of human adaptation and use of 

natural resources and is often expressed in the way land is organized and divided, patterns of 

settlement, land use, systems of circulation, and the types of structures that are built. The 

character of a cultural landscape is defined both by physical materials, such as roads, buildings, 

walls, and vegetation, and by use reflecting cultural values and traditions” (DO #28: Cultural 

Resource Management Guideline, 1998a). 
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Purpose and Need 13 

The entire Ash Meadows area has been identified as a potential Cultural Landscape by the 

Timbisha Shoshone Tribe and Pahrump Paiute, with Devils Hole being one landmark inside of 

the greater landscape. However, since all of the impacts associated with this project will be 

occurring at Devils Hole, which has also been identified as a potential Traditional Cultural 

Property, tribal use of the site is discussed under Ethnographic Resources. 

Museum Collections

The NPS’ Management Policies 2006 and DO #28, Cultural Resource Management Guideline 

(1998a) require the consideration of impacts on museum collections (historic artifacts, natural 

specimens, and archival and manuscript material). None of the items in the park’s museum 

collection, nor those on display in the visitor center, would be affected by the Proposed Action. 

Therefore, Museum Collections was dismissed as an impact topic in this document. 

Indian Trust Resources

Secretarial Order 3175 requires that any anticipated impacts to Indian Trust Resources from a 

proposed project or action by Department of the Interior agencies be explicitly addressed in 

environmental documents. The Federal Indian Trust responsibility is a legally enforceable 

obligation on the part of the U.S. to protect tribal lands, assets, resources, and treaty rights, and it 

represents a duty to carry out the mandates of Federal law with respect to American Indian and 

Alaska Native Tribes. No Indian Trust Resources are designated within the project area, and no 

portion of the project area is held in trust by the Secretary of the Interior for the benefit of any 

American Indian tribe or group. Therefore, Indian Trust Resources was dismissed as an impact 

topic in this EA. 

Lightscape Management

In accordance with NPS Management Policies 2006, the Park strives to preserve natural ambient 

lightscapes, which are defined as those that exist in the absence of human-generated light. The 

Park also strives to limit the use of artificial outdoor lighting, using only what is necessary for 

basic safety requirements. 

The Proposed Action would not affect outdoor lighting. Any short-term lighting necessary for 

public safety would be directed downward to reduce unnecessary illumination, and use would be 

restricted. Therefore, Lightscape Management was dismissed as an impact topic in this EA. The 

effect on the pupfish of reductions in direct sunlight due to shading from the proposed visitors 

platform is discussed in the section on Threatened and Endangered Species (Section 4.2.3.5). 

Land Use

The proposed project would not change the land use of the Devils Hole site. It will still be 

dedicated to the recovery of the pupfish, and to visitor interpretation of the site. If the No Action 

alternative were chosen, and site security continued to degrade over time, it could possibly result 

in further degradation and perhaps elimination of the pupfish. If this scenario were to unfold to 

its conclusion and the pupfish were eliminated from Devils Hole, the federal water right could be 
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Death Valley National Park Devils Hole Site Plan 

Purpose and Need 14 

overturned by the appeals of private interests. This in turn could lead to additional groundwater 

pumping by developers in the Amargosa Valley, in pursuit of further development in the region. 

Ultimately, the pace of development in the Valley would quicken, hastening land use changes. 

However, this chain of events, if it ever began to unfold, would do so over decades and would be 

heavily litigated. At this point, it is purely speculative. Therefore, land use was dismissed from 

further analysis in this EA. 

Waste Management

Construction activities would generate a small amount of solid, sanitary, and landscape/ 

vegetative waste; it is anticipated that no hazardous wastes would be generated. All construction 

wastes, including asphalt, rebar, and masonry materials, would be temporarily stored, 

transported, and disposed of in approved disposal facilities, at remote distances, in accordance 

with State and Federal laws and regulations and NPS policies. Soils removed from construction 

activities would be reworked into the landscape via aeration and re-vegetation activities once 

construction is finished. Existing disposal facilities have sufficient capacity to accommodate 

these wastes. No long-term impacts on waste management would occur as a result of any of the 

alternatives. Therefore, this topic was dismissed from further analysis in this EA. 

Environmental Justice

According to the U.S. Environmental Protection Agency (USEPA), environmental justice is the 

fair treatment and meaningful involvement of all people, regardless of race, color, national 

origin, or income, with respect to the development, implementation, and enforcement of 

environmental laws, regulations and policies. Fair treatment means that no group of people, 

including a racial, ethnic, or socioeconomic group, should bear a disproportionate share of the 

negative environmental consequences resulting from industrial, municipal, and commercial 

operations or the execution of Federal, State, local, and tribal programs and policies. 

Presidential Executive Order 12898, General Actions to Address Environmental Justice in

Minority Populations and Low-Income Populations, requires all Federal agencies to incorporate 

environmental justice into their missions by identifying and addressing the disproportionately 

high and/or adverse human health or environmental effects of their programs and policies on 

minorities and low-income populations and communities. The alternatives would not have 

disproportionate health or environmental effects on minorities or low-income populations or 

communities as defined in the USEPA’s Draft Environmental Justice Guidance (July 1996). 

Therefore, Environmental Justice was dismissed as an impact topic in this EA. 

Socioeconomic Issues

The Proposed Action and alternative are small construction projects, which would provide a 

small number of construction jobs on a temporary basis to local/regional workers. These jobs, 

expected to number fewer than 15 full-time equivalent jobs, producing roughly $50-60,000 in 

direct labor costs, could most likely be filled by contracting with firms in the southern Nevada 

area. Any housing needs for temporary laborers could be easily accommodated in the Pahrump 

area. In addition, construction materials would likely be available from within the region, in 

quantities too small to have more than a negligible economic impact. 
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Purpose and Need 15 

There would be no permanent jobs created by the project, and it is not expected to bring 

additional visitors and/or tourism expenditures to the Park or the Refuge. Therefore its 

socioeconomic impact is dismissed as an impact topic in this EA. 
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Alternatives 16 

2.0 ALTERNATIVES CONSIDERED 

 

2.1 NO ACTION ALTERNATIVE

Council on Environmental Quality (CEQ) regulations (40 CFR 1502.14) require the assessment 

of the No Action alternative in NEPA documents. The No Action alternative provides a basis for 

comparing the management direction and environmental consequences of the proposed action 

and must be considered in every EA. 

Under the No Action alternative, none of the project activities would be undertaken: no 

improvements or replacements would be made to the security fence, and no enhancements would 

be made to the intrusion detection capability; no changes would be made to the interpretive 

treatment or themes; no changes would be made to the access ladder or monitoring platform to 

improve researcher safety; no changes would be made to restore natural water and sediment 

flows from the watershed into the Hole; no efforts would be made to improve the overall visitor 

experience; and no revegetation plan would be developed for the project area. 

The figures referred to are located in Appendix A. Figure A-1 displays a schematic of the No 

Action Alternative. 

2.2 ALTERNATIVES ANALYZED IN THIS EA 

Each alternative analyzed in this EA consists of specific configurations of the following project 

components: 

• Fenceline boundary 

• Visitors platform, access trail, and Interpretive Treatment 

• Access stairway into Devils Hole for scientific staff 

• Monitoring platform & equipment 

• Intrusion detection security system & additional viewing cameras 

• Telecommunications infrastructure 

• Power supply 

• Habitat restoration 

2.2.1 ALTERNATIVE A (THE PREFERRED ALTERNATIVE) 

Figure 2.1 displays an overall site schematic of Alternative A. 

 

Fenceline

Alternative A consists of retaining the existing perimeter chainlink fence, with the addition of 

1200 linear feet (length dimension supplied by NPS) of chainlink fencing in the form of a 

'dogleg' that extends further from Devils Hole than the current fence, so as to allow for more 

natural drainage and sediment passage (Figure A-2). Existing chainlink along the south 

boundary, which would become unnecessary (approximately 125 ft), will be removed and stored 
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Alternatives 17 

Figure 2.1. Alternative A (Preferred Alternative) 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 18 

for reuse elsewhere. To improve the aesthetics of the site, 164 linear feet of perimeter fence 

along the east boundary will be new Twinbar High Security fence & hardware in standard gray 

color with double angled tops strung with barbed wire. One hundred sixteen linear feet of this 

Twinbar type fence will be installed on the existing east perimeter fenceline. Twenty-four linear 

feet (equal to 3 panels) will be used to turn the northeast corner. Twenty-four linear (equal to 3 

panels) will be used to turn the southeast corner. An opening in the fence equal to one panel (8 

ft.) will allow visitor access to the trail leading to the Visitors' Platform. See description below. 

This Twinbar fence length will also include one 6' wide gate (two 3' panels) installed using high 

security hardware, on the east perimeter north of the visitors tunnel, for staff access to the 

Southeast corner of the fenced area. The entire fence would be 8’ high. To further enhance 

drainage, a flood gate would be constructed along the natural drainage pathway in the 'dogleg ' 

fenced area. 

Demolition will include removal of that portion of chainlink fencing that to be replaced by 

Twinbar fencing (with possible storage for reuse). Then the existing fencing and gate under the 

existing Visitors' Platform will be removed and disposed of. 

The new chainlink material and posts for the construction of the 'dogleg' and floodgate will be 

moved into place by pick-up truck or Bobcat on tracks, equipped with a bucket. A large posthole 

drill, probably run off the Bobcat, will be used to dig the holes, which will minimize site 

disturbance. Site disturbance will also be minimized by confining vehicles to a path parallel to 

the fenceline rather than criss-crossing the site. Batches of concrete for post footings will be 

moved into place by pick-up truck or Bobcat bucket. The floodgate spillway will not be covered 

in concrete at this time. Fence installation will be done by installing posts every 8 feet using a 

large post hole drill along the perimeter, installing the 10.6-foot galvanized aluminum posts into 

non-shrink poured concrete. The posts will be dug two feet deep. 

Visitors Platform, Access Trail & Interpretation

In Alternative A the existing viewing platform would be retained. The fencing and gate beneath 

the platform will be removed using hand tools and a pickup truck. 

 

The trail to the Visitors' Viewing Platform and the platform itself will be enclosed in a tunnel 

over the existing trail from the east perimeter fenceline (Figure A-3). This tunnel will be 

constructed of 185 lf of Twinbar High Security fence panels (90 linear feet on each side of the 

trail and 5 feet enclosing the end of the Visitors' Platform). From the 8' wide entrance the tunnel 

will taper to 4.5 feet wide (3.5 feet walkway plus 6" either side to accommodate posts), entirely 

enclosed and excluding visitors from the site. Two uncovered viewing openings, each three feet 

long and 18 inches high, will be cut out of the new Twinbar High Security fence. The windows 

will be placed so one is placed for easy adult viewing, the other for easy child viewing. The 

Twinbar fence of which the tunnel will be made will not include the double angled tops. Instead 

the tunnel will be covered over by a rounded hoop of chainlink fabric. The hoops will be 

fabricated by bending standard chainlink fence poles the same outside diameter of those used for 

the 'dogleg'. (The 1/2 circle diameter bend of the post will be (in most cases) 4.5 feet (width of 

walkway), making the height in the center of the tunnel 2.25 ft high. These hoops will be welded 

to standard chainlink fence posts and installed inside-site side of the Twinbar Fence. The same 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 19 

type of chainlink fabric that will fence the 'dogleg' will be used to cover the tunnel hoops (only). 

A tension band will be woven in and out of the Twinbar Fence to secure the chainlink fabric to 

the hoops. A 3́-ft (single panel) gate opening out will be created on the south side of the tunnel. 

No additional paving will be added to the existing trail, but other trail upgrades such as steps or 

waterbars would be implemented as necessary for safety and to control trail erosion. 

The interpretive theme for Alternative A is based on combining enhanced off-site interpretation, 

through the use of a full-motion video cam located in the crevasse of the site that transmits over 

the Internet, with a joint Death Valley/Ash Meadows web site dedicated to Devils Hole 

interpretation. This website will be featured in an interpretive display at the Ash Meadows 

Visitors Center and Death Valley National Park's Furnace Creek Visitor Center. The display 

would likely also include a video of a Tribal elder talking about the importance of Devils 

Hole/Ash Meadows. The underwater video enabled in this alternative represents a significant 

improvement the Park’s ability to interpret the ecosystem. 

Access Ladder

For Alternative A, the existing ad hoc ladder is replaced by a steep incline stairway commonly 

referred to as a ships ladder (Figure A-4). Starting at the location of the existing support, the 

ladder descends 13’ at a 68 ̊ incline into the hole. The existing support would be replaced with a 

4” structural steel square tubing. Like the existing support, the new support spans both walls so 

that the top of the staircase does not impede the natural drainage. New anchors may have to be 

drilled for this support, if the existing support’s anchors are found to be inadequate. 

Two methods of anchoring the ladder support are possible: 

• A 6" square plate is welded or bolted to the each side of the support. For each plate, 4 

holes for 1⁄2" diameter anchor bolts are drilled into the rock surface to a 6" depth. 4- 1/2" 

x 8" long adhesive anchor bolts hold the plate slightly above the rock surface. Grout is 

added underneath each plate to remove all gaps. 

• An 8" hole is made in the rock for each anchor location using a core drill. The core depth 

should be 1 1/2-2’ for the ladder supports. The support is located in the center of holes 

and concrete is poured around it to form a solid concrete anchor. 

The new support has mounting brackets for the ships ladder. These brackets create a pivot at the 

top of the ladder. The bottom legs of the ladder rest on small concrete blocks atop the natural 

surface. The pivots would allow the ladder to swing in the event of a large flood. However due 

to the geometry of the ladder, only large boulders would have enough momentum to move the 

ladder. 

The ladder’s incline is steep enough that handrails would be required on both sides of the ladder 

to safely ascend and descend. 

The ships ladder would be fabricated offsite. Due to the ladder’s size and weight, along with the 

difficult access to the Hole, a crane would be required for the installation. However, since the 

ships ladder will be fully constructed prior to the install, the time and labor spent onsite will be 

minimized. 
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Alternatives 20 

Monitoring Platform & Equipment

Alternative A consists of a sectional portable monitoring platform that could be stored away 

from the water surface within the Devils Hole crevasse and assembled as needed (Figure A-5). 

The platform consists of individual aluminum sections shown in Figure A-6. A five-ft section 

would weigh approximately 40 lbs. 

The first platform segment is constructed with two rods permanently fixed to both its north and 

south end. The remaining platform sections are similar but only have one rod fixed on the north 

end of the platform. (Figures A-7, A-8). When set in place, the rods from each platform section 

rest on permanently installed anchors. Anchors shown in Figure A-5 are attached to both the 

east and west walls and provide a stable means of support for the platform. Anchor holes would 

be drilled using industrial power hand tools, such as a 1- 9/16" (13.7 lb.) rotary hammer. There 

are 10 anchor plates, each with four anchor bolts, so a total of 40 1⁄2” diameter holes would be 

required. Holes would be 4-6” deep. 

The platform is also constructed with a built-in measurement system to allow researchers to 

easily georeference their sampling locations (Figure A-9). A ruler sits freely in a slide which can 

move freely along the length of the platform to determine the coordinates of any location of 

interest. Grids are created by marking 2 points along the axis of the ruler, then sliding the ruler a 

number of inches, and marking 2 more points along the ruler, as shown in Figure A-10. 

In this alternative, the entire stilling well and frame structure will be removed and the Park will 

rely on pressure transducers and a new staff gage (the existing staff gage is connected to the 

stilling well) to measure water level. The Park will attempt to use existing anchors to affix the 

new staff gage in a location along the east wall that is easily accessible from the south shore, but 

it may be necessary to install two new anchor bolts in the east wall as necessary. Given that the 

current access scenario for conducting monitoring involves resting a ladder on the existing frame 

structure, the new access platform will be installed before removing the existing frame and 

stilling well. The existing frame and stilling well are bolted to anchors set in the east wall. 

These anchors will be left in place and the stilling well frame simply unbolted. In the event that 

an anchor is frozen, the Park would use a pneumatic cutting device similar to the “jaws of life” 

used in vehicle accident extrications. This will limit the amount of disturbance to pupfish and 

their habitat. 

Security System

For Alternative A, one of the existing cameras on the communications tower would be replaced 

with a full-motion video camera (#1) and the second would be replaced with a video camera with 

infrared (IR) capability (#2). See Figure A-11. A video recorder and transmitter interface with 

compositing software would enable images from multiple cameras to be displayed on a single 

monitoring screen; this would enhance remote monitoring capabilities. Camera feeds could also 

be switched in software. In addition, two video cameras that could transmit full-motion video 

images over the internet for site interpretation and resource monitoring would be installed within 

the crevasse, one along the cliff (#3) and one on the cavern ceiling (#4). See Figure A-12. A 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 21 

remote monitoring system, along with improved intrusion detection via intrusion sensors located 

at multiple access points, would be installed. 

A fifth camera on the visitor platform or up the hillside would be installed (#5). Lastly, a 

waterproof camera would be suspended from a cable and hung in the water at a fixed depth (#6). 

A cable would bring the video signal back to an electronics enclosure mounted remotely but 

fairly close by. The electronics processes the signal and develops the recordable video signal. 

This camera is fairly small (4"x6" cylinder). The best method of suspending it in the water will 

be determined. 

Installing higher end video cameras would cause minor disturbance of the area around the tower 

to replace and re-wire cameras #1 and #2. Installing the cameras in the crevasse (#3 on the cliff 

and #4 in the cavern) would involve drilling into the cliff face and the cavern ceiling to mount 

the camera supports, and extending buried cable from the solar power inverter to the camera 

mount. Installing camera #5 on the visitors platform would require installing a mounting post 

and routing cable as well. As mentioned above, minimizing vibration while drilling into rock for 

the camera mounts is an important consideration, because of the proximity of sensitive fish to the 

cliff face. A 13.7-lb rotary hammer would be used for rock drilling. 

Communications Infrastructure

Alternative A, which requires at least 640kbps of upstream bandwidth (but would optimize at 

1MB or higher), would use either satellite or microwave communications for transmitting data 

and images to the Ranger Station and other interpretive sites. This would involve installing a 

small satellite or microwave dish. If the dish cannot be installed on the communication tower, it 

would be mounted on a 3’ by 3’ concrete pad. Over 100’ of fiber optic cables from the video 

controller to the satellite or microwave dish would be buried underground. 

Power supply

After considering other ways of providing power (see Section 2.3), the Park is proposing to use 

solar power for all its onsite power requirements in both alternatives. 

The Preferred Alternative would require 575 watts of power for the cameras and monitors, plus 

excess power to recharge the batteries. This requires approximately 300 square feet of 

photovoltaic cells. The array (15′ x 20′) would be bracketed and mounted onto the ground at a 

location west of the Hole, chosen to balance the desire to minimize visibility and maximize 

power efficiency, with the large storage batteries stored underneath (and thus shaded by) the 

solar array. The solar power system is sized to provide 24-hour power for the site as well as 2 

days of backup of battery storage during reduced solar power input due to poor weather 

conditions. 

The panels will face as closely as possible to the south. In order to minimize the required depth 

and diameter of support footings, the panel frame will be mounted on six 2-1/2” or 3” diameter 

posts, with three posts located at the center and on either end on the upper and lower areas of the 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 22 

frame. Posts will be anchored in concrete footings, approximately 2’ diameter and 3’ deep (to be 

determined by the solar panel vendor during final design). 

The panels will be adjusted face on an angle of approximately 50o, which provides a midrange 

compromise to the sun’s elevation from winter to summer. 

Site revegetation

Much of the project area has been previously disturbed and remains sparsely vegetated. All 

revegetation plans will be conducted in consultation with Park Service botanists. Restoration in 

Alternative A would consist of: 

• Replicating the mix of plant species in the restoration area by: 

o Making a count of the genus and species of plants and the percentage of each in 

the five acres surrounding the area to be restored. 

o Raising or acquiring the appropriate mix of local species 

o Handplanting the site with minimal soil disturbance 

• After planting, lightly spraying the area with water and then minimally covering the root 

zones with stones to hold in moisture and installing fiber rolls at the top of Devils Hole to 

prevent and water runoff into the Hole (fiber rolls or logs are made of coconut fiber, rice 

wattle and wheat wattle inside a jute mesh). 

• Continue watering 1 acre with .5" of water twice per week for three weeks or as specified 

by the Park's botanist. 

2.2.2 ALTERNATIVE B 

Figure 2.2 depicts Alternative B. 

Fenceline

For Alternative B the fence will consist of 176 lf of Twinbar High Security fencing with double 

angled tops (outriggers) and hardware, and one 6' gate on the east perimeter and 2350 lf of 

chainlink fence to enclose the natural drainage (Figure A-13). However there will be no access 

to the Visitors' Platform except with a ranger guided tour, so the gate will be permanently locked 

and accessible only to Park personnel. 

Construction of the fenceline in this alternative is similar to that of Alternative A. 

Demolition will include removal of the portion of chainlink fencing to be replaced by Twinbar 

fencing (with possible storage for reuse). Then the existing fencing and gate under the existing 

Visitors' Platform will be removed and disposed of offsite.
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Death Valley National Park Devils Hole Site Plan 

Alternatives 23 

Figure 2.2. Alternative B 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 24 

Visitors Platform, Access Trail, and Interpretation

In Alternative B the existing Visitors' Platform will remain. The existing fencing and gate 

underneath this platform will be removed. 

The existing trail to this platform will remain and a wooden handrail will be installed on both 

sides of the trail (Figure A-13). These handrails will be approximately 75 ft long (total 150 ft) 

and consist of two horizontals along the trail. On both sides and the end of the Visitors' Platform 

the railing will consist of three horizontals (total length 45 ft), conforming in strength, spacing, 

horizontal and vertical support to NPS standards for railings. The railing sections will be prefabricated off-site and supports installed in the ground using a posthole drill for railings supports 

along the trail and a wood drill to attach the supports to the existing platform. Site disturbance 

will be minimal. 

The interpretive approach in Alternative B is to limit unsupervised access to the Viewing 

Platform, but with improved interpretive displays outside the fenced area for the casual visitor 

that will provide additional information about the pupfish, the ecosystem and the importance and 

need for protection. The supervised tours provide the opportunity to deliver a more complete 

message about these issues. In addition, an offsite interpretive exhibit at the Ash Meadows 

Visitors Center and Death Valley's Furnace Creek Visitor Center will be enhanced by providing 

refreshed still images of the pool from a camera inside the crevasse. The display would likely 

also include a video of a Tribal elder talking about the importance of Devils Hole/Ash Meadows. 

Access Ladder

Alternative B leaves the existing access ladder as is but increases safety and accessibility by 

adding a permanent handrail down the side of the cliff (Figure A-14). At the bottom of the 

ladder, the handrail continues down the remaining 40’ to the water’s edge. The handrail is 

constructed of 1 1⁄2” round structural steel tubing, with support posts placed every 8’. The railing 

is cut, welded, and painted onsite. 

Each handrail support post will require it own anchoring. As with the ladder support, two 

methods of anchoring the handrail supports are possible: 

• A 6" square plate is welded to the bottom of each post and support. For each support, 4 

holes for 1⁄2" diameter anchor bolts are drilled into the rock surface to a 6" depth. 4- 1/2" 

x 6" long adhesive anchor bolts hold the plate slightly above the rock surface. Grout is 

added underneath each plate to remove all gaps. 

• A 6" hole is made in each anchor location using a core drill. The core depth should be 

10" for the handrail posts. Posts are located in the center of holes and concrete is poured 

around them to form a solid concrete anchor. 

Anchor holes for the handrail supports, placed every 8’, would be drilled using industrial power 

hand tools, such as a 1- 9/16" (13.7 lb.) rotary hammer. Such hammers have a large fan and 

attachable dust collectors to minimize the deposition of shavings and small rock materials down 

the cliff and into the Hole. 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 25 

Monitoring Platform & Equipment

The monitoring platform in Alternative B is an implementation of the design produced for the 

Park by HDR FishPro, in which the platform is bolted to the east wall in a hinged manner which 

could be lowered by use of a hand-operated pulley system when required. The platform is 

permanently stored in a raised position bolted to the eastern cliff above the pool (Figures A-15 & 

A-16).

This platform structure would be installed by setting up temporary scaffolding over the cliff face. 

(It may be possible to use ropes and harnesses stretched from the top of the hole). Up to six 1-

inch anchor holes will be drilled into the cliff face. Anchor holes for the handrail and steps 

would be drilled using industrial power hand tools, such as a 1- 9/16" (13.7 lb.) rotary hammer. 

Such hammers have a large fan and attachable dust collectors to minimize the deposition of 

shavings and small rock materials down the cliff and into the Hole. 

Vibration tests, as mentioned above, would be performed in the rock before drilling. 

After anchor bolts are in place, the platform itself would most likely need to be lowered into the 

hole and into place by a small crane. If the platform is light enough to be carried down into the 

hole, such equipment may not be necessary but scaffolding spanning the water would be required 

to fasten the platform to the anchors. 

For this Alternative, the stilling well and associated frame will be removed and installed in the 

back of the cave. Installation in the new location will require drilling several new holes for 

anchor bolts to affix the stilling well frame. Though under this alternative the existing staff gage 

along with the stilling well will be moved to the back of the cave, there will also be a second 

staff gage installed along the east wall at a location easily accessible from the south shore, as in 

the preferred alternative. As in the other alternative, the Park will attempt to utilize existing 

anchors but may need to drill two new holes to set additional anchors. Given that the HDR 

access platform design cannot be fully installed without first removing a portion of the stilling 

well frame (i.e., they occupy the same space), a temporary working surface will need to be 

suspended above the water surface during removal of the existing infrastructure and installation 

of the new platform. 

Security System

For Alternative B, one of the existing cameras on the communications tower would be 

refurbished to full functionality (#1) and the second would be replaced with a camera with 

infrared (IR) capability (#2). See Figure A-17. Both of these cameras would be steerable and 

have video recording capability, although only one would be configured to transmit video; the 

other would transmit still motion images to the Ranger Station, controlled by the video software. 

The camera locations on the communications tower would remain approximately the same as 

today. A remote monitoring system, along with improved intrusion detection via intrusion 

sensors located at multiple access points, would be installed, with additional zones to cover the 

wider fenceline area. Video monitors would be located at the Ranger Station to display still 

motion images. A third camera would be installed on the northeast face of the cliff wall to 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 26 

monitor and view the Hole itself. A fourth camera would be installed on the ceiling of the 

cavern to look outward. The cameras could be camouflaged from view of the visitors to some 

extent. 

Given that this alternative has the fenceline extending almost up to the watershed edge, an 

additional security camera (#5), installed atop the visitors platform but capable of steering 

towards the upper hillside, would be needed to provide coverage of the extended area. 

Refurbishing and replacing existing cameras on the communications tower would involve minor 

disturbance of the area around the tower to replace and re-wire the cameras. Installing the 

cameras in the crevasse would involve drilling into the cliff face and the cavern ceiling to mount 

the camera supports, and extending buried cable from the solar power inverter to the new 

locations. Installing an additional steerable camera on the visitors platform would require 

installing a ground mount, and burying cable as well. Similar procedures as described for 

Alternative A would be used to minimize vibration and rock debris being transmitted into the 

Hole. 

Communications Infrastructure

Alternative B would use cell phone transmission for the communication of the limited data 

generated: alarm signals, still images, and voice communications. There is currently cell 

reception at the site. No additional hardware or software would be installed. 

Power Supply

Alternative B would require approximately 480 watts of power for the cameras and monitors. 

This would in turn require roughly 200 square feet of photovoltaic cells, along with a battery 

charging system and power conditioning. The array would be bracketed and mounted onto the 

ground at the same location as the existing array, with the large storage batteries stored 

underneath (and thus shaded by) the solar array. 

Site revegetation

Much of the project area has been previously disturbed and remains sparsely vegetated. All 

revegetation plans will be conducted in consultation with Park Service botanists. Restoration in 

Alternative B would consist of: 

• Accelerating the re-establishment of the natural mix of plant species 

o Moisten the approximately 2 acres to be restored 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 27 

o Continue to water the area twice per week with .5" water three weeks in the 

spring and most likely local plants will seed themselves. 

2.3 ALTERNATIVES CONSIDERED BUT DISMISSED

CEQ regulations for implementing NEPA require that Federal agencies explore and objectively 

evaluate all reasonable alternatives to a Proposed Action, and briefly discuss the rationale for 

eliminating any alternatives that were not considered in detail. This section describes 

alternatives to the Proposed Action that were considered and eliminated from further study. The 

rationale for elimination is given below, by alternative. 

1) Bridge over the north side of Hole 

Since one of the objectives of the action is to improve the interpretative and educational 

opportunities for visitors, one alternative considered was the construction of a bridge over the 

north side of the hole. This would orient visitors looking south over the hole and beyond, 

thereby giving them a broader view of the entire setting than a platform looking north. A 

separate interpretive area would be constructed adjacent to the bridge. 

Because of physical site limitations, this bridge would have to extend directly over the Hole 

itself. This was thought to be infeasible because: 

 Such a construction would be prohibitively expensive in relation to its benefits for the 

recovery of the pupfish 

 While providing a broader view of the setting and thereby providing additional 

educational opportunities for understanding the role of the site in the broader ecosystem, 

the actual views of the Hole itself would be limited except for directly underfoot, which 

is felt to be limiting for many visitors even if a glass floor were used for the bridge span. 

 It was felt that any alternative that allowed visitors unsupervised access inside the fencing 

should allow direct views of the Hole itself. Otherwise, there would be little benefit to 

allowing such access 

For these reasons, this alternative was dismissed from further consideration in the EA. 

2) Extending grid power and landline telecommunications 

Currently all activities at the site requiring power are served by a small solar array—3 solar 

panels, generating 37 watts, and a charge controller—located a few yards from the visitors 

platform. Data communications within and from the site are over cellular phone infrastructure. 

The proposed security and interpretive improvements will require additional power and data 

bandwidth. 

One powering option considered by the Park team was to extend grid power from a terminus 

about 1.5 miles away, within AMNWR. Power would be extended by conventional utility lines 

to the site. This would require extending above-ground utility poles and lines from the terminus 

to the site. While this is technically possible, it was considered to be unnecessarily disruptive 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 28 

and costly, as well as requiring levels of interagency negotiation that could cause delays in the 

implementation, especially given the natural suitability of solar power for the Devils Hole site. 

Similarly, telecommunications bandwidth for security and interpretive functions, using video, 

two-way voice, and internet, could be delivered by extending landlines from the AMNWR 

terminus. However, the Park team felt that similar considerations of cost, environmental 

disruption, and interagency delays make this option infeasible for this project, especially given 

the relative simplicity of a private satellite ISP system located at the site. 

For these reasons, this alternative was dismissed from further consideration in the EA. 

3) Joining the monitoring platform directly to the ladder 

One of the options considered in designing a secure convenient access for researchers was 

improving convenience by constructing a single structure that included a ladder with an attached 

fold-out monitoring platform at its bottom. The Park team felt that because of the required 

length of the platform to run from its landing point to just beyond the shallow shelf in the pool, 

an attached platform could not be sufficiently stabilized on the ground and over the pool to 

provide a meaningful improvement in overall safety. 

For this reason this alternative was dismissed from further consideration in the EA. 

4) Live video monitors at interpretive station 

The Park considered the use of live video monitors as part of the proposed interpretive treatment, 

on which would be displayed full-motion video streams from the video cameras that are scanning 

the crevasse and the cavepool. This would involve locating video monitors at the interpretive 

station located at the Visitors Platform, which would receive video feeds through wired 

connections to the cameras. Given the relentless heat of Death Valley summers, where 

temperatures routinely reach 1000

 F in the daytime, the need for environmental conditioning and 

the likelihood of frequent interruptions of service make this option problematic. In addition, 

these monitors would likely be a target of attempts at theft or vandalism, creating additional 

security concerns at the site. The Park felt that a sufficiently high- quality interpretive treatment 

could be created using a combination of other media and remote viewing opportunities. 

For these reasons, the use of live monitors on-site was dismissed from further consideration in 

the EA. 

5) Reconfiguration of road and parking access to the site 

The Park considered a reconfiguration of the access for staff and researchers from the main road 

to the site. Currently, the monitoring staff accesses the site from an unimproved trail/road that 

leads from the main road through a swinging gate to a parking area, from which staff loads and 

unloads their monitoring gear and equipment to directly access the cavepool on foot. An historic 

access road connecting School Springs within AMNWR to Devils Hole (visible on site 

topographical maps) was considered for use by staff and researchers. In this way, the existing 

access road connecting the main road to Devils Hole could be reclaimed in favor of a less 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 29 

substantial foot path for visitors. The parking area could also largely be reclaimed in favor of a 

new parking area to the West. However, this alternative access route does not get researchers 

closer to Devils Hole, nor is it more convenient. In fact, it is less convenient and would require 

that staff and researchers travel an additional distance to access Devils Hole. Further, to 

resurrect this access road some repairs would likely be needed, causing some amount of surface 

disturbance. The Park dismissed this alternative following discussions with AMNWR staff in 

which the Refuge staff expressed concerns that the increased vehicular traffic and/or any road 

improvements would impact an endangered plant that lives along the route. For this reason, 

developing the alternative access route was dismissed from further consideration in the EA. 

6) Building a new visitors platform at a new location 

The Park considered two possible locations for a new visitors platform, both of which were 

intended to enhance the interpretive experience overall, while preserving the ecological balance 

of the pupfish habitat: 

• An elevated location along the ridgeline south of (further back from) the current platform, 

along an expanded fenceline. This location would be consistent with moving the fenceline 

back to accommodate enhanced drainage while keeping the platform behind the fenceline. 

Using the results of a topographical survey and staff onsite evaluations, it was determined 

that even the best possible view of the Hole from such a site would be unacceptable for site 

visitors. Further, it was apparent that to provide even a marginal view of the water surface, 

the viewing platform would need to extend at least 18’ above the ground surface, which ́

would create an unacceptable visual intrusion into the landscape setting. Thus it was 

considered infeasible and dismissed from further consideration in the EA; 

• A location at the eastern cliff-edge directly overlooking the Hole that would be available for 

supervised tours only. The Park felt there was little reason to build a new viewing platform 

at this location when a better view was available from the existing platform. Given this view, 

and the cost and the potential for construction disturbance that could directly harm the 

pupfish, this alternative was considered infeasible and dismissed from further consideration. 

2.4 ENVIRONMENTALLY PREFERRED ALTERNATIVE

In accordance with DO-12, the NPS is required to identify the “environmentally preferred 

alternative” in all environmental documents, including EAs. The environmentally preferred 

alternative is determined by applying the criteria in NEPA, as guided by the CEQ. As stated in 

Section 2.7 (D) of the NPS DO-12 Handbook, “The environmentally preferred alternative is the 

alternative that will best promote the national environmental policy expressed in NEPA (Section 

101(b)).” This environmental policy is stated in six goal statements, which include: 

1. Fulfill the responsibilities of each generation as trustee of the environment for succeeding 

generations; 

2. Assure for all Americans safe, healthful, productive, and esthetically and culturally 

pleasing surroundings; 

3. Attain the widest range of beneficial uses of the environment without degradation, risk to 

health and safety, or other undesirable and unintended consequences; 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 30 

4. Preserve important historic, cultural, and natural aspects of our national heritage, and 

maintain wherever possible, an environment which supports diversity and variety of 

individual choice; 

5. Achieve a balance between population and resource use which will permit high standards 

of living and a wide sharing of life’s amenities; and 

6. Enhance the quality of renewable resources and approach the maximum attainable 

recycling of depletable resources (NEPA, 42 USC 4321-4347). 

In sum, the environmentally-preferred alternative is the alternative that not only results in the 

least damage to the biological and physical environment, but also best protects, preserves, and 

enhances historic, cultural, and natural resources. 

The Park selected its Environmentally Preferred Alternative by comparing the natural and human 

impacts for each project component: 

Fenceline—Alternative A expands the existing fenceline to include more but not all of the 

watershed that drains into Devils Hole, with a floodgate installed within the fence to allow 

natural sediment flows to reach the Hole. This “dogleg” fenceline would install less linear 

fencing, and thus require substantially less fencing material and construction disturbance than 

Alternative B, which extends the fenceline to encompass the entire drainage area. The dogleg 

fenceline of Alternative A provides improved natural drainage to the Hole, but natural flows are 

still artificially constrained by the fence. Furthermore, releases through the floodgate 

concentrate flows along a relatively narrow channel, increasing the flow rate and the probability 

of soil erosion. Alternative B would create more disturbance during installation, but these 

impacts would be short-term, compared to the long-term benefits from restoring fully natural 

drainage. Therefore, the fenceline in Alternative B is environmentally preferred. 

Visitors Platform, Access & Interpretation—Both alternatives retain the existing visitors 

platform and remove the fencing below. Alternative A constructs an enclosed access trail and 

encloses the visitors platform itself, thereby allowing more secure unsupervised use, and 

preventing off-trail disturbance. Alternative B eliminates unsupervised access and adds 

supervised interpretive tours, thereby precluding the need for enclosures around the trail and 

platform. The enclosure of the platform and trail in Alternative A will cause more construction 

disturbance than Alternative B, as well as detract from the visitor experience and cultural 

integrity of the site by its intrusive visual presence. Both alternatives will similarly improve the 

interpretation material onsite and at the Visitors Center, but supervised tours provide a further 

opportunity for visitor education. Therefore, the trail and interpretation of Alternative B provide 

a lighter footprint and greater opportunity for education; thus Alternative B is environmentally 

preferred for these components. 

Access Ladder—The ships ladder in Alternative A would improve safety and convenience for 

researchers by a greater amount than the handrails in Alternative B. While Alternative A could 

create more disturbance during installation, the use of BMPs would minimize this, and the ladder 

will prevent researchers from disturbing the cliffside during all subsequent descents, as would 

still be necessary by repeated placement and removal of the makeshift ladder if only handrails 

were added. Therefore, the Alternative A access solution is environmentally preferred. 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 31 

Monitoring Platform & Equipment—Alternative A involves minimal construction disturbance 

for installation, and minimal disturbance during onsite assembly and use. Alternative B involves 

extensive drilling and disturbance into the cliffside and the subsequent risk of rock and sediment 

deposition, even with careful implementation of BMPs. For this reason, Alternative A is the 

environmentally preferred solution for a new monitoring platform. 

In Alternative A, the stilling well and frame are removed, whereas in B they are simply moved to 

a less intrusive location. Since the functional role of the stilling well will be performed by using 

pressure transducers to monitor the water level, removal of the equipment is environmentally 

preferred, since this produces fewer unnatural inputs into Devils Hole. 

Security System—Both systems require the same amount of disturbance in construction, 

operations and maintenance. Therefore, neither is environmentally preferred. 

Communications Infrastructure—Alternative A would require installation of a satellite or 

microwave dish for provision of broadband data and video communication, which could be 

mounted on the existing communications tower, and the burial of cable. This would create 

minor short-term disturbance but would enable superior surveillance of the site and site security 

in the long-term. As Alternative B relies on limited existing cellular service for security system 

communications, its effectiveness is limited. Due to improved protection from vandalism, 

Alternative A is the environmentally preferred communications solution. 

Power Supply—Despite the small increment in power necessary proposed in Alternative A, the 

disturbance and impacts from installing the solar arrays in both A and B would be virtually 

identical. Therefore, neither is environmentally preferred. 

Site revegetation—Both alternatives would revegetate the same area, but Alternative A would 

revegetate faster because it would involve planting rather than waiting for plants to reseed 

themselves, as in B. The faster vegetation is reestablished on the site, the less chance there is for 

soil erosion and exotic plant establishment in the disturbed soils. Thus, the revegetation plan in 

Alternative A is environmentally preferred. 

Of the project components for which an environmental advantage could be assigned, Alternative 

A prevails in four, Alternative B in two, and there is no difference for two. Because the 

environmental benefits of Alternative A include long-term protection of the ecosystem from 

vandalism, active site revegetation, and limited near-water installation disturbances, Alternative 

A is the overall environmentally preferred alternative, by a slight margin. 

2.5 PREFERRED ALTERNATIVE

The Park’s selection of the Preferred Alternative is based on balancing the multiple objectives of 

the project, which are detailed in Section 1.1. In addition to improving the natural conditions 

that will sustain the survival of the pupfish and improving visitor interpretation, these include 

enhanced security of the site from vandalism and improvements to the safety and convenience 

for ongoing research and monitoring activities. As mentioned above, the overall environmental 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 32 

benefits between Alternatives A and B are closely decided in favor of A. Alternative A also best 

achieves the project’s full objectives for the natural and human environment. 

2.6 MITIGATION MEASURES

Measures that would be implemented to minimize or avoid adverse impacts on environmental 

resources as a result of the alternatives are described below. 

Minimizing vibration while drilling into rock for support anchors is an important consideration, 

because of the proximity of sensitive fish to the cliff face. A 13.7-lb rotary hammer would 

produce vibrations of approximately 2 inches per second per second in a 1000-lb rock, and less 

than .1 inches per second per second in a 7000-lb. rock (Norton, 2006). The Park will conduct 

vibration testing on the rocks by drilling a single hole into the rock in which holes will be drilled 

and measuring and observing vibration. The largest rock sizes feasible should be used to 

minimize transmitted vibration to the hole. In addition, using the minimum size of drill bit 

adequate for the anchor hole will minimize vibration. In addition, such hammers have a large 

fan and attachable dust collectors to minimize the deposition of shavings and small rock 

materials down the cliff and into the Hole. 

During project implementation, standard best management practices (BMPs) would be used 

during all phases of construction, rehabilitation, and system operation. Adherence to these 

BMPs would control or reduce potential adverse impacts from surface water runoff, 

sedimentation, erosion, exotic species propagation, vegetation removal, and water quality 

degradation. They would also limit any adverse affects from rock drilling in close proximity to 

the water surface. In addition to these measures, other measures would be implemented to 

minimize or avoid adverse impacts on environmental resources as a result of the action 

alternatives. These other measures are listed below. The NPS would implement these measures 

as part of either of the action alternatives. Adherence to the following mitigation measures, in 

conjunction with adherence to all applicable and appropriate local, state, and federal regulations 

and permits, should ensure that the proposed action has no significant impacts to the 

environment. 

Soil & Water Resources 

• BMPs at construction sites typically consist of erosion and sediment control measures 

such as silt fences, straw bales, soil moistening, and other temporary measures to be 

placed along portions of the site perimeter to control erosion during construction 

activities; 

• These temporary erosion prevention measurements should be maintained in place until 

the site vegetation is firmly established and soil has stabilized; 

• Regular inspections of the erosion and sediment control measures should be performed 

after any storm event; 

• The amount of vegetative clearing during construction activities should be minimized in 

order to protect the soil cover and minimize erosion risks; 

• Under all circumstances, sediment runoff from the site should be captured and prevented 

from entering any nearby surface or groundwater; 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 33 

• Care should be taken when working on the cliffs surrounding Devils Hole; workers 

should avoid erosion of sediment and soils into the Hole to the maximum extent possible; 

• Project components along the cliff (access ladder, monitoring platform anchors) should 

incorporate the natural contours of the cliff edges into their design and installation to the 

extent possible; 

• All fuels should be stored and maintained in a designated equipment staging area to 

reduce the potential for soil contamination; 

• To the extent possible, fence construction will be done from outside the fenceline, not 

inside, to minimize the flow of construction waste and sediment erosion into the Hole 

• A person(s) should be designated as being responsible for equipment fueling who closely 

monitors the fueling operation, and have an emergency spill kit containing absorption 

pads, absorbent material, a shovel or rake, and other cleanup items, readily available on 

site in the event of an accidental spill. 

• The area of disturbance should be limited. For example, heavy construction equipment 

would be kept on the road surface when placing slope protection or performing 

excavation adjacent to the roadway, to the extent possible. 

• Construction areas would be identified by and fenced with construction tape, snow 

fencing, or some similar material prior to any construction activity. The fencing would 

define the construction zone and confine activity to the minimum area required for 

construction. All protection measures would be clearly stated in the construction 

specifications, and workers would be instructed to avoid construction activities beyond 

the construction zone, as delineated by the construction zone fencing. Construction 

materials would be stored in previously disturbed areas. 

• Topsoil would be removed and stockpiled for reapplication to disturbed areas when 

construction is complete. 

• Disturbed areas would be restored to natural contours to the extent possible to reduce the 

potential for erosion. Revegetation with native species would use genetic stocks 

originating in the Park or from plants previously removed from the construction area 

whenever possible. Revegetation efforts would be designed to reconstruct the natural 

spacing, abundance, and diversity of native plant species. 

• Subsequent to project completion, Park staff would monitor and require removal of any 

invasive species observed. 

• Construction vehicles could leak fluids into the soil, introduce noise pollution, and emit 

pollutants to the atmosphere. To minimize this possibility, equipment would be checked 

frequently to identify and repair any leaks, mufflers would be checked for proper 

operation, and only equipment that is within proper operating specifications would be 

used. 

• Fuel and oil services for construction machinery would be provided in a designated area 

away from channels or drainages. This would include secondary containment for all fuel 

storage tanks and on-site availability of a specialized spill kit to contain fuel spills. 

• Biological soil crusts would be identified, staked, and flagged by NPS personnel to 

delineate areas near but outside the work areas that are not to be disturbed. 

• Gravel and fill for construction or maintenance would be obtained from certified noxious 

weed-free sources. Gravel pits and fill sources would be inspected to identify weed-free 

sources. There would be no quarrying of construction materials from inside the park or 

from AMNWR. 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Alternatives 34 

Biological Resources 

• Any area of undeveloped land would be restored as closely as possible to its original 

condition through soil stabilization BMPs and revegetation with native plants. 

• Approval would be obtained prior to the use of any outside fill materials – in order to 

ensure that any fill/seed materials are certified weed-free. 

• Construction activities would be timed to minimize impacts to pupfish survival 

behaviors. Construction activities would not take place during spawning periods, which 

typically occur between February and May. 

• To the extent possible, construction activities would be timed to avoid sensitive periods 

such as when barn owls are nesting in the cavern or western pipistrelle (Pipistrellus 

hesperus) or Townsend's big-eared bat (Corynorhinus townsendii) are present. 

• All electrical equipment should be properly grounded 

• Crews will not work in storms 

• Exposed wires will be kept as far away from Devils Hole as possible 

Air Quality 

• Implementation of reasonable measures, such as applying water to exposed surfaces or 

stockpiles of dirt, would occur when windy and/or dry conditions promote problematic 

fugitive dust emissions. Adhering to these BMPs would minimize any fugitive dust 

emissions. 

Cultural Resources 

• If previously undiscovered archeological resources are uncovered during construction, all 

work in the immediate vicinity of the discovery would be halted until the resources could 

be identified and documented, and an appropriate mitigation strategy developed in 

consultation with the Nevada State Historic Preservation Office. In the event that human 

remains, funerary objects, sacred objects, or objects of cultural patrimony are discovered 

during construction, provisions outlined in the Native American Graves Protection and 

Repatriation Act (25 United States Code §3001) of 1990 would be followed. 

Park Operations 

• Any area with vegetation clearing or construction activities would be a safety closure 

area requiring the use of hard hats. 

• Others specific to protection of site-specific features 

Visitor Use and Experience, Visitor Safety, and Traffic and Congestion 

Measures designed to minimize visitor disruption would be developed prior to construction. 

Generally accepted methods to protect public health and safety while providing for visitor use 

and experience include, but would not be limited to: 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Alternatives 35 

• Notification to travelers about site closure would be posted at both the Refuge and Park 

Visitors Centers 

• Well-tuned construction equipment with properly operating mufflers would be used and 

work would be performed during low visitation periods. For example, potential blasting 

of rock would occur during winter months when site closure would impact fewer visitors. 

• The multiple environmental benefits of the proposed action would be explained to 

visitors to maximize public support and understanding. For example, there could be an 

interpretive display at the Ash Meadows Visitor Center and Death Valley's Furnace 

Creek Visitor Center emphasizing the fragility and importance of the Devils Hole pupfish 

and its surrounding ecosystem. 

Any potential for vehicle traffic congestion around the site could be mitigated by the use of a 

slower speed limit (and accompanying signage).

2.7 COMPARISON OF ALTERNATIVES

Table 2-1 compares the alternatives, along the dimensions of the features developed to meet 

project objectives. 

Table 2-1. Comparison of Alternatives 

Project Objective No Action Alternative A Alternative B 

Security 

 Security System Existing system 

retained

Additional components 

(intrusion detection, replace 

2 cameras to transmit fullmotion video, add 2 with 

wider overall site view, and 

redundant systems added

Additional components 

(intrusion detection, refurbish 

2 cameras transmitting still 

images, add 1 with wider 

overall site view) 

 Communications • No video 

transmission 

capabilities onsite (only 

recording)

• Data telemetry 

provided via 

cell phone 

signal

• Live video provided from 

2 points above ground and 

inside crevasse for 

security and site 

interpretation, plus two 

cameras on the comm. 

tower, and one underwater 

live video feed. One 

additional live video feed 

could be available from 

the visitors platform

• Dedicated Satellite or 

Microwave Dish

• Still imagery of site 

routinely obtained (i.e. a 

webcam)

• Data telemetry provided via 

cell phone signal

 Power Individual 

components 

powered by 

Solar panel array (300 sq. 

ft), battery charging system, 

and power conditioning 

Solar panel array (180 sq. ft), 

battery charging system, and 

power conditioning system 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Alternatives 36 

Project Objective No Action Alternative A Alternative B 

dedicated solar 

panels (60 sq. ft)

system installed to power 

electronic equipment and 

incorporated into the 

interpretive themes of the 

site.

installed to power electronic 

equipment

Interpretation 

Visitors platform, 

trail, interpretation

Existing platform 

retained and 

modified as 

necessary to 

increase 

handicapped 

accessibility

• Existing platform 

retained; unsupervised 

access

• Fully enclosed visitors 

tunnel leads from 

fenceline opening to 

platform

• Live video feeds from 

Devils Hole to Visitors 

Center 

• Increase wayside and 

platform onsite displays 

provided to interpret 

ecosystem

• Existing platform retained

• Gate in fenceline leads to 

railed access trail

• Supervised tours only

• Increase wayside displays 

outside the fenced area and 

in visitors parking area 

provided to interpret 

ecosystem

Monitoring & 

Research 

 

 Access Stairway Access into Devils 

Hole provided via 

a temporary ladder 

in the SW 

drainage, little 

permanent 

footprint.

Existing access ladder 

replaced by permanentlyaffixed ship’s ladder in the 

SW drainage

Existing access ladder 

enhanced by permanent railing 

fixed to west side of cliff, with 

single handrail from stair 

landing to the base of crevasse

 Monitoring •Access to water 

surface provided 

via an 

improvised 

platform

•Retain stilling 

well and 

associated 

framing in 

existing 

configuration

• Removable sectional 

access platform deployed 

from SE shore 

• Remove existing stilling 

well and frame and rely 

on pressure transducers 

for water level monitoring

• Mechanical fold-down 

access platform deployed 

from eastern rock wall 

(HDR)

• Move existing stilling well 

to back of Devils Hole cave

Natural 

Processes 

 

 Habitat Restoration Disturbed areas 

allowed to follow 

their natural 

succession

Active replanting of 

replicated mix of native 

plant species 

Allow natural succession

 Fencing Existing fence, • Security fence is moved • Security fence is moved 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Alternatives 37 

Project Objective No Action Alternative A Alternative B 

chain link, 8’ high, 

crosses drainage

back (“dogleg” version) 

to improve sediment 

passage through 

drainage bottom

• Entire fence is 8’ high 

Twinbar, with double 

outriggers (angled tops 

facing in and out); 

• Flood gate

back to encompass the 

majority of the watershed 

(“watershed version”)

• 90% of fence is 8’ heavygauge chain link with 

single outrigger, with 

~200’ of Twinbar with 

double outrigger in the 

Visitors Platform area

Table 2-2 compares the alternatives by their environmental impacts of Devils Hole resources. 

Table 2-2. Impact Comparison of Alternatives 

Impact Topic No Action 

Alternative 

Alternative A Alternative B 

Soils Adverse, long-term, 

minor, and mediumranged impacts to soils 

from continued risk of 

erosion and disturbance 

due to visitor use and 

monitoring activities. 

Adverse, short-term, 

minor, and mediumranged impacts to soils 

due to construction 

activities. Beneficial, 

long-term, minor and 

medium-ranged impacts 

to soils due to the 

addition of new fencing, 

enclosed visitors trail and 

researcher facilities.

Negligible cumulative 

impacts to soils. 

Adverse, short-term, 

minor, and mediumranged impacts to soils 

due to construction 

activities; more intensive 

than Alt A (more fencing 

and more disruption 

from monitoring 

platform). Beneficial, 

long-term, minor and 

medium ranged impacts 

to soils due to the 

addition of new fencing, 

enclosed visitors trail and 

researcher facilities.

Negligible cumulative 

impacts to soils. 

Water 

Resources 

Adverse, short-term, 

minor, and localized 

impacts to Devils Hole 

from each monitoring 

session; adverse, longterm, minor and 

localized impacts to 

Devils Hole from 

potential erosion due to 

visitor use and 

fenceline location.

Adverse, short-term, 

minor, and mediumranged impacts to both 

surface and groundwater 

due to construction 

activities. Beneficial, 

long-term, minor and 

medium-ranged impacts 

to both surface and 

groundwater due to 

limited restoration of 

natural surface water flow 

Adverse, short-term, 

minor, and mediumranged impacts to both 

surface and groundwater 

due to construction 

activities. Higher risk 

than Alt A of rock 

deposition from 

monitoring platform. 

Beneficial, long-term, 

moderate and mediumranged impacts to both 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Alternatives 38 

Impact Topic No Action 

Alternative 

Alternative A Alternative B 

and decrease in potential 

erosion.

Potentially adverse, 

moderate, long-term, and 

project area-wide 

cumulative impacts to 

surface and groundwater 

from proposed water 

projects.

surface and groundwater 

due to a fuller restoration 

of natural surface water 

flow and decrease in 

potential erosion.

Potentially adverse, 

moderate, long-term, and 

project area-wide 

cumulative impacts to 

surface and groundwater 

from proposed water 

projects.

Vegetation Adverse, long-term, 

negligible and localized 

impacts to vegetation 

from access to cavern. 

Potentially adverse, 

long-term, negligible 

and localized, 

cumulative impacts 

from proposed 

transportation 

upgrades in the 

adjacent AMNWR.

Adverse, long-term, 

minor and localized, 

impacts on vegetation 

from the installation of 

new facilities. Beneficial, 

long-term, minor and 

localized impacts from 

habitat restoration, 

improved access to the 

cavern for researchers, 

and limitation of access 

to improved trails.

Potentially adverse, longterm but negligible and 

localized cumulative 

impacts from proposed 

transportation upgrades 

in the adjacent AMNWR.

Adverse, long-term, 

minor and localized, 

impacts on vegetation 

from the installation of 

new facilities. Beneficial, 

long-term, minor and 

localized impacts from 

replanting of native 

species, habitat 

restoration, improved 

access to the cavern for 

researchers, and 

limitation of access to 

supervised tours.

Potentially adverse, longterm, negligible and 

localized, cumulative 

impacts from proposed 

transportation upgrades 

in the adjacent AMNWR.

Wildlife Adverse, short-term, 

negligible and localized 

impacts to wildlife 

from vehicles using the 

roadway, visitation, and 

monitoring of 

conditions in the cavern

Potentially adverse, 

long-term, negligible 

and localized 

cumulative impacts 

from proposed 

Adverse, short-term and 

long-term, negligible and 

localized impacts to 

wildlife from temporary 

displacement during 

construction activities 

and the permanent 

exclusion of large 

terrestrial wildlife species 

from the fenced area.

Potentially adverse, 

short-term, negligible and 

Adverse, short-term and 

long-term, negligible and 

localized impacts to 

wildlife from temporary 

displacement during 

construction activities 

and the permanent 

exclusion of large 

terrestrial wildlife species 

from the fenced area.

Potentially adverse, 

short-term, negligible 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Alternatives 39 

Impact Topic No Action 

Alternative 

Alternative A Alternative B 

transportation 

upgrades in the 

adjacent AMNWR

localized cumulative 

impacts from vehicles 

using the roadway, 

visitation, monitoring 

activities, and proposed 

transportation upgrades 

in the adjacent AMNWR

and localized cumulative 

impacts from vehicles 

using the roadway, 

visitation, monitoring 

activities, and proposed 

transportation upgrades 

in the adjacent AMNWR.

Threatened and 

Endangered 

Species 

Adverse, long-term, 

major and localized 

impacts to the Devils 

Hole pupfish due to 

habitat alterations 

caused by the existing 

fence.

Adverse, long-term, 

major and localized 

cumulative impacts to 

the Devils Hole pupfish 

from past groundwater 

pumping, monitoring 

activities, and proposed 

future water projects.

Beneficial, long-term, 

moderate and localized 

impacts to the Devils 

Hole pupfish from 

replacement of the 

existing fence to restore 

natural sediment flow 

into Devils Hole.

Adverse, long-term, 

major and localized 

cumulative impacts to the 

Devils Hole pupfish from 

past groundwater 

pumping, monitoring 

activities, and proposed 

future water projects.

Beneficial, long-term, 

moderate and localized 

impacts to the Devils 

Hole pupfish from 

replacement of the 

existing fence to restore 

natural sediment flow 

into Devils Hole.

Adverse, long-term, 

major and localized 

cumulative impacts to the 

Devils Hole pupfish from 

past groundwater 

pumping, monitoring 

activities, and proposed 

future water projects.

Visitor Use and 

Experience

Adverse, major, longterm impacts from site 

degradation

Both adverse and 

beneficial, minor, and 

long-term. While 

visitors might perceive 

the enclosed tunnel and 

platform negatively, the 

interpretive experience 

itself will be enhanced 

by the addition of 

improved interpretive 

material, 

complemented by the 

offsite exhibits and web 

site.

Beneficial, moderate, 

and long-term impacts. 

Interpretive experience 

will be enhanced by 

tours and improved 

interpretive material 

The offsite interpretive 

exhibits web site will 

further enhance the 

overall visitor 

experience. 

Park 

Operations 

Adverse, moderate, 

long-term impacts from 

security failures and 

safety risks. 

Beneficial, moderate, and 

long term, from increased 

researcher safety and 

improved deterrence.

No cumulative impacts

Beneficial, major, and 

long term from further 

improvements in 

researcher safety and site 

security.

No cumulative impacts

Cultural Adverse, major, long- Minor, beneficial, long- Minor, beneficial, 
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Death Valley National Park Devils Hole Site Plan 

Alternatives 40 

Impact Topic No Action 

Alternative 

Alternative A Alternative B 

Resources term impacts from 

continued 

degradation of the 

habitat conditions 

that sustain the basis 

of its cultural value

term affect from 

protection of the water 

resource; Impossible to 

analyze impact of 

access restrictions 

specifically without 

further knowledge of 

affected tribes’ actual 

use. 

Visual impact of fence 

enclosure could be 

perceived by the tribes 

to be major. 

The improvements will 

have minor beneficial 

impact by increasing 

public awareness of the 

unique and fragile 

nature of the site and 

the importance of its 

preservation

long-term affect from 

protection of the water 

resource; Impossible to 

analyze impact of 

supervised tour 

restrictions specifically 

without further 

knowledge of affected 

tribes’ actual use. 

Visual impact of fence 

enclosure could be 

perceived by the tribes 

to be major. 

The improvements will 

have minor beneficial 

impact by increasing 

public awareness of the 

unique and fragile 

nature of the site and 

the importance of its 

preservation
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Affected Environment 41 

3.0 AFFECTED ENVIRONMENT 

3.1 SOILS AND GEOLOGY

The soils found in this region are located on relict alluvial fans, some derived from limestone and 

dolomite and others derived from old lacustrine and beach sediments. The soils immediately 

surrounding the project site at Devils Hole are predominantly of the Commski and CommskiYermo Associations, with Sanwell-Commski Association soils occurring just south of the site. 

The Commski soils are typically very gravelly to fine sandy loams. The upper layers of these 

soils can be up to 55 percent pebbles, and 30 percent cobbles. Only minor amounts of clay (5-

15% are present). Overall, they’re well-drained with very low to medium amounts of runoff and 

moderate permeability (NRCS, 2006; NRCS, 2001a; NRCS, 2001b). 

The Yermo soils are deeply formed, well-drained soils that also have a high percentage of gravel 

occurring in their upper layers. The cobbly to gravelly sandy loam is typically comprised of up 

to 25% cobbles or gravel (NRCS, 2001a). These soils have medium to rapid runoff rates and 

moderately rapid permeability. Sanwell soils are also very deeply formed, well-drained soils. 

They’re found on shallower slopes than both the Commski and Yermo soils; Sanwell soils form 

on slopes between 0 – 8% while both Commski and Yermo soils can be found on slopes upwards 

of 50% (NRCS, 2006; NRCS, 2001b). 

Debris and Sediment Flow into Devils Hole 

Energy input to Devils Hole results from sunlight, the resulting photosynthesis, and from organic 

materials that are carried into the fissure from the surrounding area. These materials can include 

the soils described above, any organic plant material, windborne particles, and other materials 

carried in by water and terrestrial animals. Precipitation events that cause runoff and erosion 

likely supply a large portion of this debris into the fissure. The precise amounts of these 

materials are uncertain, but they are thought to be vital to the Devils Hole ecosystem – 

particularly as food sources for the pupfish (Riggs and Deacon, 2002). 

3.2 WATER RESOURCES

3.2.1 Groundwater & Hydrogeology 

Geologic History

Throughout the Paleozoic (570-225 million years ago [mya]), the Ash Meadows region was a 

warm, tropical, beach environment that experienced repeated rise and fall of sea levels. This 

resulted in a series of sand, mud, and carbonate deposits that varied based on distance from the 

rising and falling seas: carbonates – such as limestone and dolomite – were deposited in 

submerged oceanic environments, while sand deposits occurred on adjacent beaches and mud 

deposits occurred in brackish and freshwater lagoons further inland. As sea levels fluctuated, 

these deposits layered on top of one another. The carbonate rocks present today formed from the 

calcium carbonate shells of marine organisms that lived in the shallow seas during this time 

(Riggs and Deacon, 2002). 
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Death Valley National Park Devils Hole Site Plan 

Affected Environment 42 

At the beginning of the Mesozoic (approximately 200 mya), the sea withdrew from the Death 

Valley area and Sierra Nevada became a chain of volcanoes. At this point, volcanic intrusions, 

uplift, and erosion displaced previously deposited sediments, eventually creating basin and range 

topography. The early Cenozoic (between 70 – 30 mya) saw the region begin to expand in an 

east-west direction. This resulted in the thinning out of carbonate deposits and the rise of basin 

and range topography. While this east-west expansion was occurring, north-south fractures and 

joints opened up throughout the carbonate rocks which led to the creation of subterranean 

fissures and openings. These are the most conductive flow paths for groundwater currently 

(Riggs and Deacon, 2002). 

Around 20 mya, the Death Valley region began to look as it does today; a series of linear 

mountains separating elongated valleys. Between then and now, volcanic activity, thrust faulting 

and erosion continued and basins filled up with water, creating lacustrine environments. Within 

the last million years, alluvial fans, playas, salt pans and sand dunes have all developed (USGS, 

2004). The continued tectonic and karst activities have resulted in a heterogeneous 

hydrogeologic area that includes both porous carbonate rocks and less permeable lacustrine, 

palustrine and alluvial deposits. 

Devils Hole is a fissure, formed about 60,000 years ago by a regional expansion of Paleozoic 

carbonate rocks caused by tectonic activity. Fissures in this region serve as an extensive 

drainage network transmitting water and snowmelt from the Spring Mountains. This series of 

drainage pathways has been created by groundwater dissolving units of fractured limestone and 

dolomite, creating what is known as karst topography and water-bearing rock units, or aquifers 

(Riggs and Deacon, 2002). Groundwater within this particular aquifer originates as rainwater 

and snowmelt falling on the Spring Mountains and infiltrates into the carbonate aquifer as it 

travels downslope (USGS, No date). 

The current geologic characteristics of Devils Hole include a main chamber that extends 

approximately 23 m downward and a series of rock slabs that have fallen off the main cavern 

walls. Some of these rocks have fallen off the northeast wall below the photic zone where the 

pupfish live (the photic zone is the pool depth sufficiently exposed to sunlight for photosynthesis 

to occur) and some have fallen off near the land surface, creating a shelf-like region of rocks 

(Riggs and Deacon, 2002). 

Hydrogeologic Characteristics

Groundwater is scarce, and plays an important role throughout Death Valley National Park, 

AMNWR, and Devils Hole. The quality, quantity and depth to groundwater vary greatly 

throughout this region. The dominant groundwater flow direction in the Ash Meadows sub-basin 

is from northeast to southwest with discharge locations at Ash Meadows, Oasis Valley, Alkali 

Flat and Death Valley. Dominant groundwater flow direction in the Alkali Flat-Furnace Creek 

Ranch sub-basin is from north to south. While general groundwater flow information is known, 

the specific conduits and amounts are difficult to estimate (USGS, No date; USFWS, No date; 

USGS, 1976). 
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Death Valley National Park Devils Hole Site Plan 

Affected Environment 43 

Devils Hole is within the Ash Meadows Drainage Basin which also houses the AMNWR. The 

Refuge was created in 1984 in response to declining levels of water within Devils Hole that 

threatened the pupfish. Irrigation and other pumping activities within the Ash Meadows 

Drainage Basin lead to a drastic decline in water levels within Devils Hole. Studies were done to 

determine the extent of the impact area – i.e., the area within which groundwater withdraws 

would lead to a decline in water level in Devils Hole. It was determined that withdrawals from a 

series of wells within the southwestern portion of Ash Meadows had the most direct impact on 

water levels within Devils Hole. This resulted in the creation of the NWR in this area in order to 

prevent groundwater from being removed within the area where it would result in declining 

levels in Devils Hole (Belcher, 2007). 

Water levels within Devils Hole have varied over the last 60,000 years. From 60,000 until 

approximately 15,000 years ago, the water table was at least 5 m higher than it is currently. This 

decrease in the water level is associated with the end of the last glaciation. Water levels change 

due to barometric pressure, tides, earthquakes, and groundwater pumping. Earthquakes have 

caused changes in water levels by altering bedrock locations and causing both openings and 

closings within the already fractured bedrock. Devils Hole serves as a telling seismograph: the 

presence of certain algal communities at, above, or below the current water level can indicate 

past water levels and the speed at which they changed. Water levels at Devils Hole are 

monitored continuously by a recorder attached to a float in a stilling well (USGS, 1993)—see 

Figure 3-1. Current and recent water levels are approximately 15m (49.2 ft) below the land 

surface, or 818m (2358 ft.) above mean sea level (Wilson and Blinn, 2007). Fluctuations in 

climate have also impacted water levels throughout the history of Devils Hole, though this 

relationship is not well understood at a relatively short time scale. 

Over the past several decades, water level fluctuations within Devils Hole and nearby wells have 

been linked primarily to pumping in the vicinity of Devils Hole, and secondarily to earthquake 

activity and possibly climate change. Between the 60s and the late 1970s, water levels within 

Devils Hole declined; this was during a period of active groundwater withdrawal in the region. 

Throughout the 1980s, water levels in these same wells rose, until the late 1980s when water 

levels declined through 1997. This is linked to the curtailment of pumping in the region. Water 

levels rose between 1998 and 1999, due to a significant earthquake in 1999. Following this 

earthquake, water levels began to decline and continued to do so through 2005. In addition to 

responding to groundwater pumping activities, further analysis of this data by comparison to 

other wells indicates that natural processes other than recharge rates – most likely earthquakes 

and fluctuations in climate – impacted water levels within this region (USGS, 2002; Back, 2008). 

From approximately 60,000 years ago until about 15,000 years ago the water table at Devils 

Hole was at least 5 meters higher than it currently is. At that point, after the end of the last major 

glaciation, the water table began to fall and declined rapidly. Aside from minor fluctuations that 

occurred in recent decades, as discussed above, water levels declined until they reached 

approximately the current level (Riggs and Deacon, 2002). 

Other geological characteristics in the region include a buried fault that runs southwest into the 

project region and a series of springs that seep out for approximately 10 miles within the vicinity 

of Ash Meadows (USGS, 1999). These springs are formed as a result of the juxtaposition of the 
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Death Valley National Park Devils Hole Site Plan 

Affected Environment 44 

less permeable lacustrine, palustrine and alluvial valley-fill deposits against the highly soluble 

and subsequently porous carbonate rocks, resulting in the impediment of flow beneath the land 

surface. Groundwater that travels through the carbonate aquifer eventually reaches points where 

it cannot continue due to the presence of less permeable rocks which have been shifted along the 

fault. In this instance, groundwater is forced through the path of least resistance which leads to 

the formation of springs at the land surface (USGS, No date). 

3.2.2 Surface Water 

The only surface water within the vicinity of the project area is Devils Hole itself. As the 

groundwater travels through the karst topography, it precipitates calcium carbonate due to its 

supersaturated nature. Devils Hole is not considered to be “true karst” topography, but was most 

likely formed as a result of tectonic activity (Back, 2008). Devils Hole is exposed to the surface, 

and is considered to be a “skylight to the water table” because of its hydrologic connection to the 

underlying aquifer. 

While Devils Hole is the predominant surface water feature in the area, there are numerous 

springs, seeps, and wetlands in the surrounding area (USFWS, No date; NPS, 2002). These 

features are most likely all hydrologically connected, however due to the heterogeneity of the 

geology here, it is difficult to determine the exact connections. Approximately 5 miles to the 

northwest of Devils Hole is Carson Slough which drains from a marshy region formed by 

Fairbanks Spring. Directly to the southeast of the site are a series of springs including Point of 

Rocks Spring, King Spring, Jack Rabbit Spring and Big Spring (USGS, 1993). These springs 

discharge an average of 17,000 acre-feet/year of water (USGS, No date). 

Water Quality

Within the upper reaches, or photic zone, of the 300+ foot deep Devils Hole, the water 

environment is warm, rich in dissolved carbonate and has a relatively neutral pH. The lower 

reaches of the fissure maintain relatively stable temperatures and levels of dissolved oxygen 

while the photic zone experiences greater variation due to heat and gas transfers that occur near 

the surface (Shepard et al., 2000). Water temperatures on the shallow rock shelf that is home to 

the majority of the pupfish range from 320 to 36.50 C, (900 to 980 F); they vary based on season, 

time of day and amount of direct sunlight. The deeper reaches of the Devils Hole fissure 

typically range in temperature from approximately 33.5 to 340

C, as is typical of most 

subterranean water/cavern systems (LCER, 2007).. 

Some recent studies have indicated that the water temperature on the ledge where the pupfish 

live is reaching an upper maximum threshold for successful reproduction by the pupfish. If this 

proves to be true, any further increase in temperature or drop in water level that results in an 

increase in temperature could drastically impact the population (LCER, 2007; Riggs and Deacon, 

2002). 

Water chemistry within the Ash Meadows drainage basin is relatively uniform and Devils Hole 

has remained relatively chemically stable since the 1970s. Dominant elements include sodium, 

calcium, magnesium, potassium, strontium, and lithium. Other minor constituents in 
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Death Valley National Park Devils Hole Site Plan 

Affected Environment 45 

groundwater include boron, silica and nitrate. Natural fluctuations occur based on groundwater 

movement and time of storage within nearby aquifers. When groundwater remains stored in an 

aquifer, it becomes enriched in sodium, and to a lesser extent, sulfate and chloride (USGS, 

1976). 

3.3 VEGETATION

A creosote bush vegetation community predominates in the project area. Common plant species 

include white bursage (Ambrosia dumosa), creosote bush (Larrea tridentata), and shadscale 

(Atriplex confertifolia). Other plant species found in the immediate vicinity of Devils Hole 

include chaff bush (Amphipappus fremontii) and ephedra (Ephedra funereal), while rock nettle 

(Eucnide arens) and Parry’s lip fern (Cheilanthes parryi) grow along the rock walls of the cavern 

(Wilson and Blinn 2007). There are 63 known non-native plant species in Ash Meadows. The 

most common exotic plant species include red brome (Bromus rubens), Russian thistle (Salsola 

spp.), tumble mustard (Sisymbrium altissimum), halogeton (Halogeton glomeratus), and Arabian 

schismus (Schismis arabicus). Of these, Arabian schismus is the only exotic plant species 

documented in the project area. None of these exotic species is on the State of Nevada’s 

Noxious Weed List (Nevada, 2007). Additional plant species found in the project area are listed 

in Appendix D. 

There are no federally listed plant species known to occur in the project area. 

3.4 WILDLIFE

Over 27 species of mammals, 20 reptiles, and 239 species of birds are known to occur in the area 

surrounding Devils Hole (USFWS, 2007), but only a portion of these are associated with the 

three habitat types found at the project site: the Mojave Desert creosotebush scrub surrounding 

the cavern, the above water portions of the cavern, and the aquatic portion of the cavern. 

Wildlife species in the creosotebush scrub habitat at Devils Hole are predominately species 

associated with the Mojave Desert. Mammal species typical for this habitat type and likely to 

occur in the vicinity include desert bighorn sheep (Ovis canadensis), coyote (Canis latrans), 

blacktail jackrabbits (Lepus californicus), desert cottontails (Sylvilagus audubonii), and whitetailed antelope squirrel (Ammospermophilus leucurus). Reptile species include gopher snakes 

(Pituophis catenifer), desert iguana (Dipsosaurus dorsalis), and western chuckwalla 

(Sauromalus obesus). Bird species include Gambel's Quail (Callipepla gambelii), black-throated 

sparrows (Amphispiza bilineata) and mourning doves (Zenaida macroura). No amphibians are 

known to occur in the vicinity of the project. 

Three wildlife species are known to utilize the cavern walls above the pool in Devils Hole. Barn 

owl (Tyto alba) roost and have been observed to nest there and two bat species, the western 

piptstrelle (Pipistrellus hesperus) and Townsend's big-eared bat (Corynorhinus townsendii) are 

present seasonally (Manning, 2008). 

The aquatic community includes a single vertebrate, the Devils Hole pupfish (Cyprinodon 

diabolis). Herbst and Blinn (2003) reported a diversity of invertebrates including a springsnail 
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(Tryonia variegata), an amphipod (Hyallela azteca), a flatworm (Dugesia dorotocephala), a 

water strider (Microvelia beameri), a riffle beetle (Stenelmis calida), a predacious diving beetle 

(Neoclypeodytes cinctellus), several midges (Culicoides sp., Zavrelimyia sp., Apedilum sp., 

Chironomus sp., Polypedilum cf. scalaenum, and Tanytarsus sp.), as well as an unidentified 

stonefly, cyclopoid copepod, ostracode, aquatic worm, and water mite. Shepard et al. (2000) 

described algal diversity as low relative to other systems, reporting 84 terminal identifications 

including diatoms (Bacillariophyta), blue-green algae (Cyanobacteria), and green algae 

(Chlorophyta). To date, little work has been completed to describe Protozoan or microbial 

diversity at Devils Hole. 

3.5 THREATENED & ENDANGERED SPECIES, CANDIDATE SPECIES, AND 

SPECIES OF SPECIAL CONCERN

The Endangered Species Act (Act) of 1973, as amended, states “It is further declared to be the 

policy of Congress that all Federal departments and agencies shall seek to conserve endangered 

species and threatened species and shall utilize their authorities in furtherance of the purposes of 

this Act”. For federally sponsored projects, the Act requires examination of potential impacts to 

Threatened, Endangered, and Candidate Species. Section 7 of the Act requires federal agencies 

to ensure that any activities they authorize, fund, or implement do not jeopardize the continued 

existence of any species federally listed as threatened or endangered and do not destroy or 

adversely modify designated critical habitat. NPS Management Policies 2006 requires 

examination of potential impacts on federal candidate species, as well as state-listed threatened, 

endangered, candidate, rare, declining, and sensitive species with potential to occur within the 

project area. The policies also state that the NPS will fully meet its obligations under the NPS 

Organic Act and the Endangered Species Act to both pro-actively conserve listed species and 

prevent detrimental effects on these species. They further state that the NPS will undertake 

active management programs to inventory, monitor, restore, and maintain listed species’ habitats, 

control detrimental non-native species, control detrimental visitor access, and re-establish 

extirpated populations as necessary to maintain the species and the habitats upon which they 

depend. For simplicity, the federal, state, NPS and Nevada Heritage Program listed species 

identified in this EA as occurring at Devils Hole are collectively described as Special Status 

Species (Table 3.1). A full listing of federally listed species occurring in the AMNWR 

surrounding Devils Hole can be found in Appendix C. 

Table 3-1. Special Status Species Categories 

An endangered species is classified under the Endangered Species Act as being in danger of 

extinction throughout all or a significant part of its range. 

A threatened species is classified under the Endangered Species Act as likely to become an 

endangered species in the foreseeable future. 

The State of Nevada has also designated special status species on the Nevada Watchlist. Species 

with these classifications are protected under Nevada Administrative Code Chapter 503. 

The Nevada Natural Heritage Program collects information on Nevada's at risk, rare, 

endangered, and threatened biological features. Taxa considered at-risk include those with 
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federal or other Nevada agency status, and those with Global and/or State ranks indicating some 

level of imperilment. 

National Park Service sensitive species include species designated by the NPS in addition to 

those listed, proposed, or candidates under the Endangered Species Act or listed by the State of 

Nevada as endangered or otherwise protected. 

Six special status wildlife species occur in the project area: a federally endangered species, 

Devils Hole pupfish (Cyprinodon diabolis); two species listed as priority species by the State of 

Nevada, Townsend's big-eared bat (Corynorhinus townsendii) and Amargosa tryonia snail 

(Tryonia variegate); these three species, as well as the Devil’s Hole warm spring riffle beetle 

(Stenelmis calida calida), are also listed as at-risk by the Nevada Natural Heritage Program; and 

two species listed as sensitive by the NPS, desert bighorn sheep (Ovis canadensis) and western 

chuckwalla (Sauromalus obesus). The Devils Hole pupfish is endemic to Devils Hole. 

As mentioned previously, Devils Hole was designated part of the Death Valley National 

Monument in 1952 in order to protect the habitat of the Devils Hole pupfish. In the late 1960s 

groundwater pumping by ranchers and developers near Devils Hole caused water levels in the 

pool to drop so low that it put a severe strain on the pupfish population which dropped to as low 

as 124 individuals (Deacon and Williams, 1991). As a result, the Devils Hole pupfish was 

federally listed as endangered in 1967 and, in 1984, the land surrounding Devils Hole was 

purchased from developers and the 22,000-acre Ash Meadows National Wildlife Refuge was 

created (USFWS, 1990). 

Following these actions, the pupfish survey stabilized at an average of 324 individuals and 

reached a high of 582 individuals in a September 1994 survey (Riggs and Deacon, 2002). From 

1995 to 2004 the population survey declined to an average of less than 225 individuals (Riggs 

and Deacon, 2002). Then, in 2004, the population dropped dramatically following an incident 

where one third of the existing population was accidentally killed when traps used to monitor the 

fish were washed into Devils Hole by a flash flood (Florida Museum of Natural History, 2006). 

By April of 2006 the population survey had fallen to a low of 38 individuals. Fall pupfish 

surveys in 2006 and 2007 recorded 85 and 92 fish respectively (NDOW, 2008).

Though the cause of the most recent decline of the Devils Hole pupfish decline remains 

unknown, a number of hypotheses have been promoted that could singly or cumulatively be 

responsible. Factors could include inbreeding depression (Wilcox 2001), declining solar 

radiation or allochthonous nutrients (Wilson and Blinn 2007), shifts in algal community state 

(Riggs and Deacon 2005), changes in sediment dynamics (Lyons 2005; Riggs and Deacon 2005), 

loss of a key prey species (i.e., an ostracode) from the primary feeding habitat (Herbst and Blinn 

2003), continuing water level declines (Riggs and Deacon 2005; Deacon et al. 2007), and 

increasing water temperature due to global warming and/or declining water levels (Threloff and 

Manning 2003). 

The Devils Hole pupfish is a member of the Cyprinodontidae family. This species rarely 

exceeds 2.5 cm and has a life span of about one year. The species is diurnal and omnivorous, 

feeding primarily on diatoms, amphipods, ostracods, protozoans, and others (Wilson and Blinn 
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2007; Minckley and Deacon 1975).. Spawning occurs mainly on the shallow upper shelf of 

Devils Hole (Figure 3-1) between February and May. Peak spawning appears to coincide with 

the peak algal growth: between April and mid-June. Females lay small numbers of eggs, 4 to 5, 

which deposited singly onto the substrate and fertilized by the male. Pupfish reach maturity 2- 4 

months after hatching. Population levels exhibit a natural high and low cycle, with the 

population peaking in the fall and lowest in the spring due to die-off during the winter months 

(USFWS, 1980). Studies on the reproductive ecology of other pupfish taxa suggest water 

temperatures in Devils Hole are likely to be near the upper maximum threshold for successful 

egg production and recruitment of young fish into the population (Shrode and Gerkin, 1997). 

These studies also suggest small increases in water temperature on the order of a few degrees 

may be sufficient to decrease or eliminate successful recruitment. 

Figure 3-1. Sectional View of Devils Hole 

Source: USFWS

Growth and successful reproduction are closely related to the availability of food. The small 

upper shelf on which the fish spawn also provides a majority of the algae and much of the 

diatoms on which the fish feed (U.S. Fish and Wildlife Service 1980). Growth during the spring 

varies between 0.00 and 0.025 inch/week, and little or no growth occurs during the winter (U.S. 

Fish and Wildlife Service 1990). A 1975 study of the food habits of the Devils Hole pupfish 

determined that diatoms were the most important food in fall and summer (Minckley and 

Deacon, 1975). Also included in the pupfish diet are an amphipod (Hyalella), an unidentified 

ostracod, and protozoans. A beetle, (Stenelmis), planarium (Dugesia), and snail (Tryonia) are 

much less commonly used as food (Minckley and Deacon, 1975). Wilson and Blinn (2007) 

found cyanobacteria to be the most important food in summer, with a shift to Stenelmis calida

and Dugesia dorotcephala in winter. 

Another factor that shapes the mix of food sources as well as the ability of the fish to spawn 

successfully is the availability of sunlight. Direct sunlight enables algal growth, which forms a 

mat on which the fish deposit their eggs and on which the pupfish’s food sources depend for 

their own food supply. Because of its “incised morphometry” (i.e., its presence at the base of a 
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steep cliff gouged into a hillside), the pool receives less than four hours of direct light per day in 

the summer (June-August) and no direct light during December and January (Wilson and Blinn, 

2007). Currently the only manmade structure producing an impact on direct sunlight is the 

visitors platform, which reduces available light by 1.15% at the northern end of the hole, and 

1.72% at the southern end, where the upper shelf lies, the equivalent of about 15 minutes per day 

(Weiss, 2005a). 

The Townsend's big-eared bat is a medium-sized bat with extremely long ears and a small 

glandular outgrowth on each side of the snout. Distribution of this bat is correlated largely with 

rocky areas where caves or abandoned mine tunnels are available. They do not seem to utilize 

crevices in such sites, and may occasionally inhabit old buildings. In the Devils Hole area this is 

probably the most characteristic bat of caves and mines. 

Townsend’s big-eared bats are present seasonally in Devils Hole from early spring to September 

and do not appear to use it as a hibernaculum (Manning, 2008). The Townsend’s big-eared bat 

may visit or night roost in Devils Hole, but their day roost is in Devils Hole 2 (Baldino, 2008). 

Males and females occupy separate roosting sites during summer. During this season, males 

appear to lead a solitary lifestyle while females and young form maternity colonies which may 

number from 12-200. The bats emerge late in the evening to forage and are swift, highly 

maneuverable fliers. Prey items include small moths, flies, lacewings, dung beetles, and 

sawflies. The single young is born in late May to early June, at least in Texas. The baby bat 

weighs approximately 2.4 g at birth and is pink, naked, and completely helpless. At 4 days of 

age the newborn bat begins to display hair growth and by 1 month of age is nearly adult size. At 

2 months of age the juveniles are weaned and the nursery colonies begin to disperse (Texas 

Tech, 2008). 

Amargosa tryonia (tryonia variegata) is a mollusk, or more specifically a gastropod, in the 

Hydrobiidae family and is the most abundant benthic invertebrate present in Devils Hole (Herbst 

and Blinn, 2003). Little is known about the biology of this mollusk. Studies have provided little 

more than taxonomic descriptions, geographic distribution, or use in the diet of Devils Hole 

pupfish. Most abundant in fall/winter (Oct – Dec – Feb) and least in spring (April) it exhibits a 

generational turnover of 4-10 months (6 months average) and principally inhabits the gravel 

substrates at the mid and lower end of the upper shelf (Herbst and Blinn, 2003). 

The Devils Hole riffle beetle is endemic to Ash Meadows NWR, found at Devils Hole and 

several warm springs (Herbst and Blinn, 2003). It is the third most common invertebrate after 

Tyronia variagata and Hyalella though total biomass production of the riffle beetle equals that of 

Hyalella.. Little is known about the biology of the Devils Hole riffle beetle though Herbst and 

Blinn (2003) found abundance to peak in October and that it is found most frequently in gravelly 

substrates at the shallow southwest end of the upper shelf. 

Desert bighorn sheep inhabit hot and dry desert mountain ranges with sparse vegetation and 

water. Their range extends from Nevada and California to west Texas and south into Mexico. 

Weights of mature rams range from 125 to 200 pounds, while ewes are somewhat smaller. Due 

to their unique padded hooves, bighorn are able to climb steep, rocky terrain with speed and 

agility. Bighorn rely on their keen eyesight to detect potential predators such as mountain lions, 
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coyotes, and bobcats, and they use their climbing ability to escape. Both sexes develop horns 

soon after birth, with horn growth continuing more or less throughout life (USFWS, 2002). 

While bighorn sheep are known to occur in the vicinity of Devils Hole, their use of the project 

area may be limited. 

Western chuckwalla, one of the largest lizards in Nevada, are locally common and widely 

distributed in rocky habitats throughout the region. The Western chuckwalla's range covers eastcentral California, southern Nevada, southwestern Utah, western Arizona, and northeastern Baja 

California. Prime habitat is boulder covered slopes, at elevations of up to 6000 feet, though it is 

most common at lower elevations. Western chuckwallas are herbivores and feed on plants such 

as brittle-bush (Encelia farinosa), but have also been known to forage on rock nettles. Mating 

occurs between April and July, with a clutch of as many as 16 eggs laid between June and 

August. The eggs hatch in the late warm season. 

3.6 VISITOR USE AND EXPERIENCE

Death Valley National Park offers a wide range of recreational and educational experiences to 

Park visitors. However, a relatively small proportion of Death Valley visitors visit Devils Hole, 

which is a 45-minute drive away and accessible only by unpaved road. 

Site-specific survey and visitation data for Devils Hole is not available. But road count statistics 

for the road that leads to Devils Hole have been collected for several years (Nalen, 2007). 

Several factors confound projection of actual Devils Hole visits from these road counts: (1) an 

unknown proportion of the cars are double-counted by the automated road counter because they 

turn around and return on the same road after visiting the site; and (2) some drivers use the road 

as a thoroughfare between Rudd Highway and Crystal, so they are counted as travelers but are 

not visitors to Devils Hole. Starting with a total of 6,793 cars counted from August 2006-July 

2007, and using conservative assumptions based on these caveats (half the visitors turn around 

after their visit, half continue ahead, and 20% use the road as a thoroughfare), the visitor number 

for the 12 months from August 2006-July 2007 was approximately 3700 cars. This is at best a 

rough approximation, but probably within the order of magnitude of actual visitation. 

According to Park Interpretive staff, many people who visit are on “Sunday drives” from local 

communities including the Amargosa Valley, Las Vegas, and Pahrump (a fast-growing 

community of approximately 35,000 people roughly halfway between Las Vegas and Devils 

Hole). Visitors from Las Vegas and Pahrump are often on a drive to get away from the city and 

just happen to find Devils Hole. In addition, a number of locals from nearby communities have a 

past personal connection to the Hole, having visited there a number of years ago. Some people 

are attracted to the site since it is labeled as a part of Death Valley National Park on some maps 

(Wolfe, 2007). 

Quite a few people are drawn to the site by its name and do not know what to expect when they 

arrive. Besides the name or having a personal connection, specific interests that draw people to 

the Hole include: pupfish, rare fish, cave diving, geology (particularly the lengthy calcite climate 

record), the landmark Supreme Court ruling associated with Devils Hole, having seen Devils 

Hole on television (a PBS Nature program from the 1970s), college level and younger classes 
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studying biology, ecology or geology, an interest in the natural world, Death Valley history (i.e. 

the Lost 49ers visit to the Hole), or collectors of killifish. 

3.7 PARK OPERATIONS

Scientific research and site security are two key activities in the implementation of species 

recovery actions at Devils Hole. These functions bear directly on Park operations and are 

discussed here. 

3.7.1 Security 

Species protection takes several forms, but physical security of the site is of paramount 

importance. The Proposed Action and alternatives are intended to enhance physical security of 

the site through improvements to the system of intrusion prevention, detection, and response. 

The Park is aware of three unambiguous security incidents in about the last two years. More 

incidents have likely occurred but there has been no evidence of any recently. One incident 

involved someone likely trying to catch some fish with a wicker basket from the upper level lip. 

A second incident caused damage to the fence from someone trying to dig under it, most likely to 

gain access to the upper area (Forner, 2007). A third incident involved someone throwing 

materials into Devils Hole. Litter has also frequently been found both within the fenced 

perimeter and within the water. 

The security system now in place has been described in Park documents as “down more than up” 

(RFP, 2007). Its current state can best be characterized as deteriorating, having been vandalized 

and robbed over the years, but never restored back to its full operating capability. 

Though it would not be prudent to further highlight the known drawbacks and limitations of the 

existing security infrastructure by detailing the system’s design in a public document, it has 

become clear that additional security measures are needed to protect the site and its fragile 

resources from vandalism. 

3.7.2 Scientific Research and Monitoring 

The research and monitoring functions at Devils Hole present significant human safety 

challenges. A primary concern is the climb down to the site. The current mode of access is by a 

stepladder which is accessed through a gate below the visitors platform. This ladder is not 

permanently fixed to either end of the climb, and the risk is compounded by the necessity of 

hauling gear and equipment into the site as well. Furthermore, the walk from the landing of the 

ladder to the pool itself is steep, rocky, and unsecured (Figures 3-2 & 3-3). 
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Figure 3-2. Ladder Access to the Site (Ladder in yellow circle) 

Figure 3-3. Descent from Ladder Landing to Pool 
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Ongoing monitoring at Devils Hole consists of two primary types of operations: 

1) Biannual Devils Hole pupfish counts—These are typically conducted by laying a 

temporary monitoring platform across the shallow shelf (see Figure 3-4). The purpose of 

this walkway is to provide physical separation between personnel and the shelf to reduce 

disturbance of the shelf from monitoring activities. One end of the walkway rests on the 

metal frame already in place for water monitoring equipment and the other end on the 

southern-most portion of the shelf. Placement and removal of the platform currently 

requires a person stepping approximately halfway between the metal frame and the 

southern edge of the shelf. A metal diving ladder is placed at the end of the walkway into 

the hold past the shelf. 

Figure 3-4. Divers Entering Devils Hole 

Fish counts include both underwater and surface counts. Underwater counts are 

conducted by experienced divers who are escorted by an NPS employee, and are 

conducted using established protocol (USFWS (BO), 2001). Surface counts on the 

spawning shelf would be conducted by three people on the walkway concurrent with the 

underwater counts. The shelf is divided into zones by imaginary boundaries, with each 

counter counting the fish within a zone. 

The monitoring platform is a temporary makeshift solution to the problem of accessing 

the submerged spawning shelf without damaging it. If it were needed only twice a year 
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for one day each, the inconvenience and personal risk associated with carrying the ladder 

down the steep rockface might be acceptable. But because the platform is needed for 

other more regular monitoring activities, the Park feels the probability of accident or 

injury calls this procedure into question. 

2) Routine Monitoring and Maintenance of Water Measurement Devices—The collection, 

maintenance, and evaluation of water level monitoring data is a critical component of the 

recovery strategy for the Devils Hole pupfish, given that the principal threat it faces is the 

loss of water over the spawning shelf. Park hydrologists maintain a “scientifically 

rigorous and court-defensible water level data base for the long range protection of the 

water level of the spring pool” (USFWS (BO), 2001). 

The water level monitoring program currently consists of the following equipment: 

a. The fixed, reference point mounted in the rock wall above the water level as 

established by the 1976 U.S. Supreme Court ruling 

b. A stainless steel, submerged equipment-bearing frame 

c. A 12-inch stainless steel stilling well mounted to the frame 

d. Two water level staff gauges mounted to the frame 

e. A 10-inch float contained in the stilling well 

f. Two pulleys mounted in the rock wall over the water surface 

g. A steel line attached to the float and connected to a recording device 

h. A Stevens A71 drum chart recorder and digital shaft encoder which are mounted 

within an enclosure affixed to the top of the stilling well 

i. Two stainless steel pressure transducers and connecting cables mounted on the 

stilling well 

j. Two independent plastic water temperature probes 

k. Shore mounted enclosure with battery power sources, data storage devices, and 

GOES satellite transmitter 

l. GPS antenna 

m. Solar panel for long-term battery maintenance 

Operation and maintenance of the facility consist of bi-monthly inspections, monthly data 

retrieval, periodic and annual maintenance. In addition, NPS staff inspect, service and replace 

equipment at Devils Hole three to five times a year. Equipment replacement needs are 

unpredictable and are required because of vandalism or major mechanical failures. Quarterly site 

inspections are also made by NPS staff to check and verify the accuracy of the staff gauges in 

relation to the reference point. 

Agency personnel that service the water monitoring equipment are trained in techniques 

designed to ensure that no contaminants are inadvertently introduced into pool waters. 

Application of chemicals, such as lubricants or solvents, is not normally permitted over the water 

surface. Accidental introduction of non-native organisms by water monitoring personnel is 

minimized by sterilizing all mechanical devices and tools that come into contact with the pool 

surface, and by the use of sterilized footwear or footwear dedicated for use at Devils Hole. 
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Additional planned monitoring activities include: (1) a long-term ecosystem monitoring effort 

which will require at least weekly access to the water surface via the monitoring platform; (2) a 

number of emergency management actions which require access to the water surface, such as 

experimental breeding and supplemental feeding trials, are being implemented to stabilize the 

population; (3) research efforts designed to study the potential causes of the observed decline in 

pupfish abundance. These also require access to the water surface. 

3.8 CULTURAL RESOURCES

Devils Hole and the surrounding AMNWR have both largely been surveyed for cultural 

resources. Thirty of the forty acres of Devils Hole, and the dry portion of the approximately 

22,000 acre Refuge were surveyed by HRA, Inc in 2007-2008. The cultural history of the area is 

discussed in Livingston and Nials (1991) and Lyons et al. (2007), and briefly summarized here. 

Native Americans have inhabited the southern Nevada region for the past 12,000 years, but 

strong archeological evidence for habitation of the AMNWR area shows up approximately 5,000 

years before present (Lyons et al 2007:4). This archaic occupation is represented by Pinto series 

points, and late archaic sites include Gypsum series points and burial pits. During the late 

prehistoric period, from approximately 1,500 to 3,800 years before present, there is evidence of 

trade (represented by exotic ceramic potsherds) with other southern Nevada groups, including 

the Virgin Anasazi (Lyons et al. 2007:10). During the late prehistoric and ethnographic period, 

there is evidence that Western Shoshone and Southern Paiute lived in the AMNWR area and 

practiced a hunting and gathering way of life, practicing some horticulture near water sources. 

Plants grown include corn, squash, beans, and sunflowers (Livingston and Nials 1990:12). 

Native American festivals were held in the AMNWR area during the fall, with people gathering 

following completion of their summer foraging (Speulda and Parks 1996:10). Euro-Americans 

reportedly first entered the AMNWR area in 1849. Two members of the Bennett-Arcan wagon 

group, William L. Manley and Louis Nusbaumer, mentioned Devils Hole specifically, describing 

it as a deep hole in the rocks with fresh, clear water (McCracken 1992:14-15 in Lyons et al. 

2007:13). 

Euroamericans homesteaded in the AMNWR area beginning in 1873, and continued into the 

midtwentieth century. A homestead occupied by a Paiute family was present approximately 2 km 

from Devils Hole, known as Bishop's Ranch. The site was reportedly burned to force the family 

to give up their land. Clarabelle Jim, a Pahrump Paiute member (who was consulted during this 

project) recalls visiting Bishop's Ranch during the 1940s and 1950s (Nevada Archeological Site 

Archives). 

Twenty-one archeological sites have been recorded within 2 miles of Devils Hole. Prehistoric 

finds include lithic reduction sites, resource processing sites, and a rockshelter with textile 

fragments. Historic period sites include trash scatters, and remnants of historic Euroamerican and 

Native American homesteads. A Native American cemetery is located near Devils Hole, and it is 

considered a sensitive resource to both the Pahrump Paiute and Timbisha Shoshone. There are 

undoubtedly more than 21 archeological sites located within 2 miles of Devils Hole, and the 

results of the HRA, Inc. Ash Meadows survey will be a valuable addition to the 

archaeological literature for the area. 
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Archeological Survey Results (DEVA 2008A) 

A majority of the Devils Hole allotment was surveyed by DEVA Park Archeologist Leah 

Bonstead and DEVA VIP Jane Rondthaler on February 15, 2008. The survey area is located in 

Section 36 of Township 17 South, Range 50 East, and is bounded by NPS boundary markers on 

all sides. The survey area is comprised of a lower section which is relatively flat and open, with 

scattered creosote and grasses, and an upper section which is very steep and rocky. In all, 30.7 

acres on the flat portion and lower slopes was surveyed, and the upper steep and rocky portion 

was left unsurveyed. Survey transects were spaced approximately 20 meters apart. Four roads are 

located in the survey area: (1) the main Ash Meadows Road, located on the east side of the 

project area; (2) an administrative use road from Ash Meadows Road to Devils Hole; (3) a closed 

road entering the Devils Hole area from the south; (4) and a closed road from Devils Hole to a 

small natural depression named Devils Hole 2. Unapproved off road vehicle tracks are also 

present in the area. 

Eleven isolated finds were found during the survey, most of which were historic or modern. 

These include a prehistoric flake, a trail segment, NPS boundary rock cairns, a prospect, and a 

glass scatter. The date of the prehistoric flake is unknown, but is probably over 100 years old. 

The historic finds appear to mostly date to the time that the NPS took over management of the 

site, though the prospect pit is probably older. As all of the remains found during the survey were 

isolated finds, they are not eligible for nomination to the National Register of Historic Places. 

The Timbisha Shoshone, a federally recognized tribe, have had a long relationship with Devils 

Hole, and have been active in the Ash Meadows area for thousands of years. One story about the 

Timbisha Shoshone relationship with Devils Hole is excerpted here: 

Evidence of the cultural significance of Devils Hole to these Native Americans was 

presented by Barbara Durham, an elder of the Timbisha Shoshone Tribe at the Devils 

Hole Workshop in Pahrump, Nevada on May 29-31, 2002. In her oral communication, 

she related the myth of Devils Hole "water babies" ready to swallow children (and 

perhaps even adults) that stayed at the pool too long. Smith (1993) refers to these water 

babies as well as to a giant, Tso'apittse, who lives near desert springs lying in wait for 

unsuspecting victims. In spite of those very powerful deterrents, Ms. Durham reported 

that she and her childhood friends frequently played at Devils Hole because they 

enjoyed having the pupfish "tickle their toes." (Riggs and Deacon 2002) 

As well, conversations with elders of the Pahrump Paiute tribe have confirmed that Devils Hole 

was very important to the Paiutes in the past, and that “their ceremonial relationship with the 

area continue[s] today.” (DEVA, 2008). The Paiute have not been specific in recent discussions 

with the Park about their relationship with Devils Hole, but previous research suggests it owes 

much to the cultural significance of the water itself, as the following excerpt describes: 

But springs meant more than survival to Southern Paiute people. Springs and other 

water sources were also highly symbolic, sacred places, part of a living landscape, a 

storied place, peopled with animals, plants and other beings that brought it life and 
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gave it meaning. Stories and songs that often include the names of springs and other 

places celebrate great hunts and other events that turn a desert into much more than 

simple geographic space. They create a landscape and a homeland that once gave, and 

in many ways still gives, people a strong sense of being and belonging – a sense of 

place. For Indian people, landscapes and homelands are often more important than 

events and time (Fowler 2002). 

Therefore, Devils Hole is believed to fit the definition of a Traditional Cultural Property, owing 

to its historic connection with the Timbisha Shoshone and Pahrump Paiute tribes. Additionally, 

both groups have identified the Ash Meadows area as a Traditional Cultural Landscape, with 

Devils Hole as one landmark within that larger landscape. As such, the Park has undertaken 

consultations with these tribes on the effects of the proposed action pursuant to Section 106 of 

the National Historic Preservation Act (further detailed in Section 5.2). The tribes are also 

allowed access to the property under The American Indian Religious Freedom Act of 1978. 
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4.0 ENVIRONMENTAL CONSEQUENCES 

This section describes the environmental consequences associated with the alternatives. It is 

organized by alternatives, so that the environmental impacts of each alternative can be considered 

together. Within each alternative, the impacts of each project component on all considered 

resources is presented. 

4.1 METHODOLOGY

NEPA requires consideration of context, intensity, and duration of impacts, direct or indirect 

impacts, cumulative impacts, and measures to mitigate the impacts. NPS policy also requires 

that “impairment” of resources be evaluated in all environmental documents. 

Overall, the NPS based the following impact analyses and conclusions on the review of existing 

literature and Death Valley National Park studies, information provided by experts within the park 

and other agencies, professional judgments and park staff insights, and public input. 

General Impact Definitions 

Potential impacts are described in terms of type (beneficial or adverse), context, duration, 

intensity, and impairment. The following general definitions were used to evaluate the context, 

intensity, duration, and cumulative nature of impacts associated with project alternatives. 

Impairment is discussed below. The specific criteria used to rate the intensity and duration of 

potential impacts for each resource (e.g., soil, water, biotic communities, etc) are presented at the 

start of each impact topic in this chapter. 

Context of Impact

Context is the setting within which an impact is analyzed, such as local, park-wide, or regional 

but must relate to the scope of the project area. CEQ requires that impact analysis include 

discussions of context. Localized impacts are those that affect only a small area within the 

project site or its immediate surroundings. 

Intensity of Impact

Impact intensity is the degree to which a resource would be beneficially or adversely affected by 

an action. Impact intensities are quantified as negligible, minor, moderate, or major. Resourcespecific criteria used to rate the intensity of project impacts are presented within each resource 

area impact analysis. 

Duration of Impact

The duration of impact is analyzed independently for each resource because impact duration is 

dependent on the resource being analyzed. Depending on the resource, impacts may last as long as 

construction takes place, or a single year or growing season, or longer. For purposes of analysis, 
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impact duration is measured in short-term and long-term. Resource-specific criteria used to rate 

the anticipated duration of resource impacts are presented within each resource area impact 

analysis. 

Direct versus Indirect Impacts

Direct impacts are effects caused by the alternative(s) at the same time and in the same location 

as the action. Indirect impacts are effects caused by the alternative(s) that occur later in time or 

farther in distance than the action, but still reasonably foreseeable. 

Cumulative Impact Scenario

CEQ regulations (40 CFR 1508.7) require the assessment of cumulative impacts in the decisionmaking process for Federal projects. A cumulative impact is an impact on the environment that 

results from the incremental impact of the action when added to other past, present, and 

reasonably foreseeable future actions regardless of which agency (Federal or non-Federal), 

organization, or person undertakes such other actions. Cumulative impacts can result from 

individually minor, but collectively significant, actions taking place over a period of time. 

Cumulative impacts are considered for all alternatives and are presented at the end of each impact 

topic discussion analysis. To determine potential cumulative impacts, projects in the vicinity of 

the proposed project site were identified. Potential projects identified as cumulative actions 

included any planning or development activity that was currently being implemented or that 

would be implemented in the reasonably foreseeable future. 

These cumulative actions are evaluated in the cumulative impact analysis in conjunction with the 

impacts of each alternative to determine if they would have any additive effects on natural 

resources, cultural resources, visitor use, or the socioeconomic environment. Because some of 

these cumulative actions are in the early planning stages, the evaluation of cumulative effects 

was based on a general description of the project. Known past, current, and reasonably 

foreseeable future projects and actions in the vicinity of the project area are described below: 

Water-Related Projects 

• The Southern Nevada Water Authority (consisting of all of the water agencies in the Las 

Vegas metro area) has proposed to develop approximately 8,000 acre-feet of ground water 

per year from an area north and northwest of Las Vegas (Tikapoo and Three-Lakes Valleys, 

immediately east of Creech Air Field, along the Highway 95 corridor). The location would 

like be roughly 35 to 45 miles east and slightly north from Devils Hole, depending on 

specific points of diversion. The uncertainties in timing and location of development, and in 

timing and magnitude of impact on Devils Hole make the project impact very difficult to 

evaluate. The time frame in which this drawdown would likely occur is 100 to 400 years in 

the future. The Nevada State Engineer ruled on these water right applications several years 

ago. However, SNWA has chosen to put the project on hold and there is no definitive 

timeline when it may be re-activated (Fisk, 2008b). 

• The State of Nevada is considering a water rights petition heard in September 2007 involving 

changes in points of diversion for irrigation pumping in the Amargosa Valley. If those 
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change applications are granted (over NPS protest), Devils Hole water levels could be 

affected. Again, there is insufficient information available to project how much the affect 

may be and when it may occur. 

• The Las Vegas metro and the Amargosa Desert are desirable areas for further development, 

and many projects are proposed for which the State of Nevada could issue water rights. For 

example, a private company is planning a solar array near Crystal, NV, about 8 miles from 

Devils Hole, which would involve groundwater pumping in the Amargosa Valley. In 

addition, as many as 9 projects using concentrated solar power are being proposed within 

about 20 miles of Devils Hole. The Park Service has the right to challenge any award of 

water rights that it can demonstrate would threaten the federal reserved water right for Devils 

Hole. No other specific actions are known at the present time, but the development pressures 

will undoubtedly continue in the region overall. 

Refuge Planning 

AMNWR is in the planning stages on several projects that could impact Devils Hole: 

• A new wayside interpretive kiosk is being planned for the southern edge of Devils Hole, with 

a minimal primitive parking area alongside. This would most likely take the configuration of 

three double-sided panels under a shade structure and brochure boxes. Further details are not 

yet available, nor is the timing of construction. 

• The Desert Refuge complex has undertaken a transportation survey that will provide 

recommendations for improvements to the existing network of roads and parking lots and 

address transportation, management, maintenance, and coordination threats and challenges 

faced by the Refuge (Ash Meadows, 2007). The goal of these improvements is to enhance 

visitor safety and to support the resource protection mission and policies of AMNWR. 

AMNWR faces numerous transportation challenges, including managing the access points to 

the Refuge and the use of existing routes. Much of the entering traffic is not destined for the 

Refuge and consists of commuters and other private and commercial vehicles passing 

through the Refuge. The high amount of through traffic, often at high speeds, generates 

environmental impacts. The USFWS strives to provide access to the public but their primary 

mission is to protect sensitive plant and animal species. 

The Refuge also faces substantial issues related to existing hydrologic and geologic 

challenges in terms of planning and maintaining a road network. The high water table and 

presence of springs near or under roadways cause significant damage to roads and often 

make segments impassable. Roadway maintenance and planning must be conducted in close 

coordination with other ongoing efforts that will affect water flow and water location within 

the Refuge, including sub-basin restoration and modifications to existing dams. 

• The Desert NWR Complex is preparing a Comprehensive Conservation Plan/Environmental 

Impact Statement (CCP/EIS) that includes four refuges: Desert, Ash Meadows, Pahranagat 

and Moapa. The CCP/EIS describes the resources, public use, goals, objectives, and 

strategies for AMNWR and for the other refuges. It also identifies potential environmental 

effects of potential actions under consideration. The CCP/EIS effort was started in 2004; the 

administrative draft has been completed; and the final draft is currently being prepared. The 
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goals of the CCP/EIS are very broad, with supplemental studies called step-down plans being 

developed to recommend more specific measures that implement CCP/EIS policies. 

• USFWS is planning to conduct a detailed visitor survey for the Refuge. For a full year, 

contractors will be at AMNWR to survey visitors and identify the types of users (such as 

local resident visitors or tourists) and characteristics of their use (such as drive through, 

hunting, wildlife observation, photography, interpretation, and environmental education). 

• Road traffic counters have been used at AMNWR, including Devils Hole, to identify the 

number of vehicles using Refuge roads. 

• The Interpretive Plan for AMNWR is also a step down plan from the CCP/EIS for the 

Complex, and includes recommendations for public access and use within the Refuge. The 

plan focuses on protecting wildlife first and then providing controlled public use where 

compatible with AMNWR’s mission. 

• The Visitor Services Plan is currently underway and will focus on the development of 

interpretive supportive infrastructure such as boardwalks. Though it is not the intention of 

USFWS to open new areas of the Refuge to vehicles, it may be desirable to focus and 

intensify uses in some areas. There are locations that offer a higher quality experience for 

the visitor and these are sites where interpretive information could be provided. Other 

initiatives under way include the development of a new visitor area and an interpretive kiosk 

at Point of Rocks. 

• An Integrated Pest Management Plan addressed issues related to the seeds of non-native and 

invasive species being disbursed by vehicles passing through the Refuge. The plan 

documents the threat posed by invasive species, noting that almost 100 invasive species are 

present in the Refuge. Some of these species can alter ecosystem processes and prevent 

habitat restoration, among other problems. 

• The Ash Meadows Geomorphic and Biological Assessment Final Report was completed in 

April 2006. This report describes the geologic and hydrological features of the Refuge and 

priorities for restoring hydrologic conditions. The natural drainage patterns of AMNWR 

have been modified for agricultural and commercial purposes. Alterations such as the 

construction of dams, roads, development of irrigation networks, and construction of Crystal 

Reservoir have altered the natural hydrologic processes within the Refuge. The Ash 

Meadows Geomorphic and Biological Assessment recommends numerous projects that 

would reestablish spring flow to historic natural channels and would therefore impact the 

desired location of roadways: 

Impairment of Park Resources

In addition to determining the environmental consequences of the Proposed Action and other 

alternatives, the NPS Management Policies 2006 and DO-12 require analysis of potential effects 

to determine if actions would impair a park’s resources. 

The fundamental purpose of the National Park System, established by the Organic Act and 

reaffirmed by the General Authorities Act, as amended, begins with a mandate to conserve park 

resources and values. NPS managers must always seek ways to avoid or minimize to the greatest 

degree practicable adverse impacts on park resources and values. However, the laws do give 

NPS management discretion to allow impacts to park resources and values when necessary and 
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appropriate to fulfill the purposes of a park, as long as the impact does not constitute impairment 

of the affected resources and values. Although Congress has given NPS management discretion 

to allow certain impacts within parks, that discretion is limited by statutory requirement that the 

NPS must leave park resources and values unimpaired, unless a particular law directly and 

specifically provides otherwise. The prohibited impairment is an impact that, in the professional 

judgment of the responsible NPS manager, would harm the integrity of park resources or values, 

including opportunities that otherwise would be present for the enjoyment of those resources or 

values. An impact to any park resource or value may constitute an impairment. However, an 

impact would more likely constitute an impairment to the extent it affects a resource or value 

whose conservation is: 

• Necessary to fulfill specific purposes identified in the establishing legislation or 

proclamation of the park; 

• Key to the natural or cultural integrity of the park or to opportunities for enjoyment of 

the park; or

• Identified as a goal in the park’s Master Plan or General Management Plan (GMP) or 

other relevant NPS planning documents. 

Impairment may result from NPS activities in managing the park, visitor activities, or activities 

undertaken by concessionaires, contractors, and others operating in the park. In this section, a 

determination on impairment is made in the conclusion statement of each impact topic for each 

alternative. The NPS does not analyze the potential for impairment of recreational values/visitor 

experience (unless impacts are resource based), socioeconomic values, or park operations. 

The sections below describe the methodology for analyzing impacts on each considered 

resource. 

4.1.1 Soils and Geology 

Impact analyses on soils were based on recent soil data from NRCS within the project area and 

on previous projects conducted within the park. 

The thresholds of change for the intensity of an impact on soils are defined as follows: 

Negligible: Soils would not be affected or the effects on soils would be below or at the lower 

levels of detection. Any effects to soils would be slight. 

Minor: The effects on soils would be detectable. Effects on soil area would be small within the 

project area. Mitigation may be needed to offset adverse effects and would be relatively simple 

to implement and likely be successful. 

Moderate: The effect on soil would be readily apparent and result in a change to the soil 

character over a relatively wide area within the project area. Mitigation measures would be 

necessary to offset adverse effects and likely be successful. 
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Major: The effect on soil would be readily apparent and substantially change the character of the 

soils over a large area within the project area. Mitigation measures to offset adverse effects 

would be needed, extensive, and their success could not be guaranteed. 

The thresholds of change for the duration of an impact on soils are defined as follows: 

Short-term: Recovers in less than three years. 

Long-term: Takes three or more years to recover. 

The context for the analyses was: 

Localized: the area including Devils Hole and its cliffs 

Medium: the area extending beyond Devils Hole to its surficial watershed 

Project area wide: the area extending beyond Devils Hole up to the boundary of AMNWR 

4.1.2 Water 

The thresholds of change for the intensity of an impact on water resources, including 

groundwater, are defined as follows: 

Negligible: Neither surface nor groundwater flow nor hydrology would be affected, or changes 

would be either non-detectable or, if detected, would have effects that would be considered slight 

and short-term. Chemical or physical changes to surface or groundwater quality would not be 

detectable, would be well below water quality standards or criteria, and would be within 

historical or desired water quality conditions. 

Minor: Changes in surface or groundwater hydrology would be measurable, although the 

changes would be small and would likely be short-term. No mitigation measure associated with 

surface or groundwater hydrology would be necessary. Chemical or physical changes to surface 

or groundwater quality would be detectable, but would be well below water quality standards or 

criteria and within historical or desired water quality conditions. 

Moderate: Changes in surface or groundwater hydrology would be measurable and long-term. 

Mitigation measures associated with surface or groundwater hydrology would be necessary and 

the measures would likely succeed. Chemical or physical changes to surface or groundwater 

quality would be detectable, but would be at or below water quality standards or criteria. 

Major: Changes in surface or groundwater hydrology would be readily measurable and would 

have substantial consequences to the project area. Mitigation measures would be necessary and 

their success would not be guaranteed. Chemical or physical changes to surface and 

groundwater quality would be detectable and would be frequently altered from desired water 

quality conditions. Chemical, physical, or biological water quality standards or criteria would be 

locally exceeded on a short-term and temporary basis. 
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The thresholds of change for the duration of an impact on water resources are defined as follows: 

Short-term: Following treatment, recovery would take less than one year. 

Long-term: Following treatment, recovery would take greater than one year. 

Context for the analysis: 

Localized: the area including Devils Hole and its cliffs 

Medium: the area extending beyond Devils Hole to its surficial watershed 

Project area wide: the area extending beyond Devils Hole up to the boundary of AMNWR 

4.1.3 Vegetation 

This impact analysis focuses on vegetation that is considered most likely to be affected by the 

project. Information on vegetation was derived from consultation with NPS staff and a review of 

relevant literature. The impact analysis examines the potential changes to vegetation that may 

occur as a result of project implementation. 

The thresholds of change for the intensity of an impact on vegetation are defined as follows: 

Negligible: No native vegetation would be affected or some individual native plants could be 

affected as a result of the alternative, but measurable or perceptible changes in plant community 

size, integrity, or continuity would not occur. The effects would be short-term and on a small 

scale. Impacts would be well within the range of natural fluctuations. 

Minor: Effects to native plants would be measurable or perceptible, but would be localized 

within a small area. The viability of the plant community would not be affected and the 

community, if left alone, would recover quickly. Impacts would not be expected to be outside 

the natural range of variability and would not be expected to have any long-term effects on 

native species, their habitats, or the natural processes sustaining them. 

Moderate: The alternative would affect some individual native plants and would also affect a 

sizeable segment of the species’ population in the long-term and over a relatively large area. A 

change would occur to the native community over a relatively large area that would be readily 

measurable in terms of abundance, distribution, quantity, or quality. Impacts could be outside the 

range of natural variability for short periods of time. Mitigation measures to offset/minimize 

adverse effects would be necessary and would likely be successful. 

Major: The alternative would have a considerable long-term effect on native plant populations 

and affect a relatively large area in and out of the park. Impacts would be expected to be outside 

the natural range of variability for long periods of time or to be permanent. Extensive mitigation 

measures would be needed to offset any adverse effects and their success would not be 

guaranteed. 
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The thresholds of change for the duration of an impact on vegetation are defined as follows: 

Short-term: Recovers in one to three years or less. 

Long-term: Takes more than three years to recover. 

4.1.4 Wildlife 

This impact analysis focuses on wildlife species that are considered most likely to be affected by 

the project. Information on wildlife species potentially present was derived from consultation 

with NPS staff and a review of relevant literature. The impact analysis examines the potential 

changes to wildlife and use of the project area that may occur as a result of project 

implementation. 

The thresholds of change for the intensity of an impact on wildlife are defined as follows: 

Negligible: Wildlife would not be affected or the effects would be at or below the level of 

detection, would be short-term, and the changes would be so slight that they would not be of any 

measurable or perceptible consequence to wildlife populations. Impacts would be well within 

the range of natural fluctuations. 

Minor: Effects on wildlife would be measurable or perceptible, but localized within a small area. 

While the mortality of individual animals might occur, the viability of wildlife populations 

would not be affected and the community, if left alone, would recover. Impacts would not be 

expected to be outside the natural range of variability and would not be expected to have any 

long-term effects on native species or the natural processes sustaining them. Sufficient habitat 

would remain functional to maintain viability of all species. 

Moderate: A change in wildlife populations would occur over a relatively large area. Effects to 

wildlife would be readily detectable, long-term, and with consequences at the population level. 

The change would be readily measurable in terms of abundance, distribution, quantity, or quality 

of population. Mortality or interference with activities necessary for survival can be expected on 

an occasional basis, but is not expected to threaten the continued existence of the species in the 

park unit. Impacts could be outside the natural range of variability for short periods of time. 

Sufficient habitat would remain functional to maintain variability of all native wildlife species. 

Mitigation measures would be necessary to offset adverse effects, and would likely be 

successful. 

 

Major: Effects on wildlife populations would be readily apparent, long-term, and would 

substantially change wildlife populations over a large area in and out of the national park. 

Impacts would be expected to be outside the natural range of variability for long periods of time 

or to be permanent. Loss of habitat may affect the viability of at least some native species. 

Extensive mitigation would be needed to offset adverse effects, and the success of mitigation 

measures could not be assured. 
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The thresholds of change for the duration of an impact on wildlife are defined as follows: 

Short-term: Recovers in one to three years or less. 

Long-term: Takes more than three years to recover. 

4.1.5 Threatened & Endangered Species, Candidate Species, and Species of Special 

Concern 

Federally listed or candidate species that could be affected by project implementation were 

identified, as were potentially affected State-listed and NPS identified sensitive species. These 

analyses were conducted in the context of the population of the species across its range. 

The thresholds of change for the intensity of an impact on threatened, endangered, and sensitive 

species are defined as follows: 

Negligible: The action could result in a change to a population or individuals of a species or 

designated critical habitat, but the change would be so small that it would not be of any 

measurable or perceptible consequence and would be well within natural variability. This impact 

intensity equates to a USFWS “no effect” or “may affect, not likely to adversely affect” 

determination. 

Minor: The action could result in a change to a population or individuals of a species or 

designated critical habitat. The change would be measurable, but small and localized and not 

outside the range of natural variability. Mitigation measures, if needed to offset the adverse 

effects, would be simple and successful. This impact intensity could equate to either a USFWS 

“may affect, not likely to adversely affect” or “may affect, likely to adversely affect” 

determination. 

Moderate: Impacts on sensitive or listed species, their habitats, or the natural processes 

sustaining them would be readily detectable. Listed or sensitive plants or breeding animals of 

concern are present; animals are present during particularly vulnerable life-stages such as 

migration or juvenile stages; mortality or interference with activities necessary for survival can 

be expected and could threaten the continued existence of the species in the park unit, but 

impacts would not extend to the broader geographical range of a species. Mitigation measures, if 

needed to offset adverse effects, would be extensive and likely successful. This impact intensity 

equates to a USFWS “may affect, likely to adversely affect” determination. 

Major: The action would result in a noticeable effect to viability of multiple populations of a 

species or resource or designated critical habitat. Impacts on a sensitive or listed species, critical 

habitat, or the natural processes sustaining them would be detectable, both in and out of the park. 

Loss of habitat might affect the viability of at least some species. Extensive mitigation measures 

would be needed to offset any adverse effects and their success would not be guaranteed. This 

impact intensity equates to a USFWS “may affect, likely to jeopardize the continued existence of 

a species or adversely modify critical habitat for a species” determination. 
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The thresholds of change for the duration of an impact on threatened, endangered, and sensitive 

species are defined as follows: 

Short-term: Impacts occur during implementation of the alternative 

Long-term: Effects extend beyond implementation, continuing to affect population, community, 

or designated critical habitat recovery. 

4.1.6 Visitor Experience 

Public scoping input and observation of visitation patterns, combined with assessment of what is 

available to visitors under current management, were used to estimate the effects of the actions in 

the three alternatives in this EA. The impact on the ability of the visitor to experience a full 

range of Devils Hole resources was analyzed by examining resources and objectives presented in 

the park significance statement. The potential for change in visitor use and experience proposed 

by the alternatives was evaluated by identifying projected increases or decreases in 

interpretational or educational experiences and other visitor uses, and determining whether or 

how these projected changes would affect the desired visitor experience and to what degree and 

for how long. 

The thresholds of change for the intensity of an impact on visitor use and experience are defined 

as follows: 

Negligible: Changes in visitor use and/or experience, including changes in noise levels and 

aesthetic resources, would be below or at the level of detection. The visitor would not likely be 

aware of the effects associated with the alternative.

Minor: Changes in visitor use and/or experience, including changes in noise levels and aesthetic 

resources, would be detectable, although the changes would be slight. The visitor would be 

aware of the effects associated with the alternative, but the effects would be slight.

Moderate: Changes in visitor use and/or experience, including changes in noise levels and 

aesthetic resources, would be readily apparent. The visitor would be aware of the effects 

associated with the alternative and would likely be able to express an opinion about the changes.

Major: Changes in visitor use and/or experience, including changes in noise levels and aesthetic 

resources, would be readily apparent and severely adverse or exceptionally beneficial. The 

visitor would be aware of the effects associated with the alternative and would likely express a 

strong opinion about the changes. 

The thresholds of change for the duration of an impact on visitor use and experience are defined 

as follows: 

Short-term: Occurs only during the treatment action. 

Long-term: Occurs after the treatment action. 
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4.1.7 Park Operations 

Park operations, for the purpose of this analysis, refers to two issues: security operations and the 

human safety of researchers and scientific staff who conduct ongoing recovery and monitoring 

operations at Devils Hole. Park staff involved with these issues were members of the planning 

team that developed and evaluated each alternative. Impact analysis is based on the current 

description of Park operations presented in Section 3.0 of this EA. 

The thresholds of change for the intensity of an impact on Park operations are defined as follows: 

Negligible: Park operations would not be affected, or the effects would be at low levels of 

detection and would not have an appreciable effect on Park operations. 

Minor: The effect would be detectable and would be of a magnitude that would not have an 

appreciable effect on Park operations. If mitigation was needed to offset adverse effects, it 

would be simple and likely successful. 

Moderate: The effects would be readily apparent and result in a substantial change in Park 

operations in a manner noticeable to staff and the public. Mitigation measures would be 

necessary to offset adverse effects and would likely be successful. 

Major: The effects would be readily apparent, result in a substantial change in Park operation in 

a manner noticeable to staff and the public, and be markedly different from existing operations. 

Mitigation measures to offset adverse effects would be needed, extensive, and success could not 

be guaranteed. 

The thresholds of change for the duration of an impact on park operations are defined as follows: 

Short-term: Effects lasting for the duration of the treatment action. 

Long-term: Effects lasting longer than the duration of the treatment action. 

4.1.8 Cultural Resources 

The cultural resources at Devils Hole are those derived from the historical, religious, and 

ceremonial traditions of use by the Timbisha Shoshone and Pahrump Paiute tribes in the region. 

The Park considers the two primary tangible resource conditions that sustain the cultural 

significance to be the water level in the Hole and access to the site. Without knowledge of which 

specific location(s) of the Devils Hole site are visited by the tribes for ceremonial purposes, it is 

not possible to specify the extent to which the fencing and security actions proposed by the Park 

will impact those purposes. Therefore, the impact analysis will consider more general site 

access, as well as impacts to the water therein. 

An intangible resource condition, harder to measure and to analyze, is the spiritual energy of the 

site, which comes through in tribal conversations and stories about the site, and emerges from the 

tribal worldview of interconnections between all realms of the natural world (Fowler, 2002). 

The Timbisha Shoshone consider that this spiritual energy is impacted by activities or equipment 
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that intrude into the water source. This EA acknowledges the difficulty of analyzing impacts in 

this framework, but acknowledges their existence nonetheless. 

In general, the thresholds of change for the intensity of an impact to cultural resources within the 

Park are defined as follows: 

Negligible: The impact would be barely perceptible and would neither alter resource conditions, 

such as traditional access or site preservation, nor the relationship between the resource and the 

affiliated group’s body of beliefs and practices. There would be no change to a group’s body of 

beliefs and practices. 

Minor: The impact would be slight but noticeable and would neither appreciably alter resource 

conditions, such as traditional access or site preservation, nor the relationship between the 

resource and the affiliated group’s body of beliefs and practices. 

Moderate: The impact would be barely perceptible and would neither alter resource conditions, 

such as traditional access or site preservation, nor the relationship between the resource and the 

affiliated group’s body of beliefs and practices. There would be no change to a group’s body of 

beliefs and practices. 

Major: The impact would alter resource conditions. Something would block or greatly affect 

traditional access, site preservation, or the relationship between the resource and the affiliated 

group’s body of beliefs and practices, to the extent that the survival of a group’s beliefs and/or 

practices would be jeopardized. 

With respect to the duration of impacts, to the extent that the cultural values of the site derive 

from the preservation and integrity of its natural resources, particularly the water, any impacts to 

cultural resources would therefore track the impacts to the water. That is, if the water level 

decreased, so would be the cultural resource value; if and when the former recovers, so would 

the latter. 
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4.2 ANALYSIS OF ALTERNATIVES

4.2.1 No Action Alternative 

4.2.1.1 Soils and Geology 

Impacts Analysis

The No Action Alternative will not have any construction-related impacts to area soils, as no 

infrastructure will be built in or around Devils Hole. If this alternative is chosen, site use can be 

expected to continue as is. This includes the use of existing monitoring and visitor 

infrastructure, including the monitoring platform and fencing system. Fencing can be expected 

to continue to limit natural sediment movement. The continued use of the monitoring platform 

and sampling techniques has the potential to cause erosion of cliff soils into Devils Hole. 

Without updated infrastructure and trails, visitors may go off existing trails, displacing 

vegetation and disturbing soils. 

Cumulative Impacts

Currently, none of the water-related or Refuge planning projects can be expected to impact soil 

resources within the vicinity of Devils Hole. Since each of these projects would exist outside of 

the Devils Hole surface watershed, no soils would be impacted and no changes to sediment 

movement would occur. Additionally, these activities would not influence any of the soils that 

supply nutrients to Devils Hole. The No Action Alternative would not contribute to cumulative 

impacts from the scenario described above. 

Conclusion

Overall, adverse, minor, long-term, and medium range impacts to soils may result from the 

implementation of the No Action Alternative, due to the continued erosion of soils from the 

manner in which the hole is accessed by researchers, and the impedance of natural sediment 

flows from the fence. 

The level of impact on soil resources would not result in impairment of park resources that fulfill 

the specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 

4.2.1.2 Water 

Impacts Analysis

Under the No Action Alternative, no changes would be made to any of the Devils Hole visitor or 

monitoring facilities. This may pose a risk to water quality within Devils Hole due to the 

potential for researchers using the makeshift system of descent to the Hole and the existing 

monitoring platform to inadvertently cause cliff sediments to loosen and wash into Devils Hole. 

These sediments could cloud the water in Devils Hole, resulting in a decrease in sunlight 
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available to the upper reaches of the Hole. Depending on the composition of the sediment, how 

much is eroded, rainfall levels, potential flooding, and whether or not any other substances being 

used on the platform combine with the sediment, the chemical composition of the water in the 

Hole could be altered. During flood events, the potential for erosion could increase, due to 

higher water levels and faster moving currents. Increased turbidity could cause an increase in 

water temperature as turbid water heats more readily when exposed to sunlight. Elevated levels 

of turbidity could also lead to decreases in primary production and dissolved oxygen levels. It is 

likely that these impacts would be short-term and dissipate shortly after monitoring activities 

stop and sediment is able to settle. These impacts would potentially re-occur each time 

monitoring is performed. All sediment movement will remain as it currently is; the existing 

fenceline will continue to limit natural drainage immediately surrounding Devils Hole. 

Additional impacts would be possible from visitors going off-trail, displacing vegetation and 

increasing the potential for soil erosion into the water. 

Cumulative Impacts

There have been major, direct and indirect adverse cumulative impacts to the water level in 

Devils Hole from past groundwater pumping activities. Each of the proposed water-related 

development projects described in the cumulative scenario has the potential to change 

groundwater levels and flow rates within the regional aquifer that includes Devils Hole. Lower 

groundwater levels within the regional karst aquifers could lead to changes in water chemistry. 

These changes may include an increase in the dissolution of calcium carbonate as less water 

travels through the same aquifer conduits. Water temperature in Devils Hole would have the 

potential to increase with a decline in water levels. Sunlight would reach further into the Hole 

and the location of the photic zone would shift as water levels declined over time. General 

regional groundwater withdraw also would have the potential to impact levels of some of the 

springs within the vicinity of AMNWR. The specific interaction of proposed groundwater use 

activities and groundwater level and quality in Devils Hole is difficult to quantify within the 

scope of this EA. Any groundwater pumping within the approximately 22,000 acre preserved 

area surrounding the Hole is most likely to impact groundwater within Devils Hole. But this is 

unlikely to occur. Each of these proposed projects would occur outside of this protection 

groundwater region; however, given the unknown hydrogeologic connections in this region, 

changes in water level in Devils Hole could occur. 

Refuge planning projects as they are currently described in the cumulative scenario are not likely 

to impact surface or groundwater in or around Devils Hole; when more detailed information and 

planning has been completed a more accurate assessment of the potential impacts can be made. 

With no construction activities, changes in drainage, or water levels occurring as part of the No 

Action Alternative, the implementation of this alternative is not likely to contribute to the overall 

cumulative impacts on water resources within the vicinity of Devils Hole. 

In addition, the likelihood of increases in global temperature that have been predicted over the 

next century could increase the water temperature of the pool (IPCC, 2008). Any increase in 

water temperature could adversely impact the pupfish, given the evidence that the pupfish may 

already be existing at the upper edge of the temperature range for sustainable spawning and 

recruitment (Shrode and Gerkin, 1997). 
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Conclusion

Overall, adverse, short- and long-term, minor, and localized impacts to Devils Hole are likely, 

due to the potential for researchers using the makeshift system of descent to the Hole and the 

existing monitoring platform to inadvertently cause cliff sediments to loosen and wash into 

Devils Hole. Additional impacts would be possible from visitors going off-trail, displacing 

vegetation and increasing the potential for soil erosion into the water. 

The level of impact on groundwater and surface water resources would not result in impairment 

of park resources that fulfill the specific purposes identified in the enabling legislation or that are 

essential to the natural or cultural integrity of the park. 

4.2.1.3 Vegetation 

Impacts Analysis

As there would be no new actions under the No Action Alternative, there would be no new 

impacts on vegetation. There would be no need to clear vegetation for the new fence or trails 

leaving the surrounding vegetation to continue to exist in its current state. Researcher visits to 

monitor conditions in the cavern would continue to cause damage to vegetation along the access 

route into the cavern. Continued cyclic maintenance of the access road and trails could also have 

adverse impacts on vegetation from vegetation removal and trampling. 

Cumulative Impacts

Plants in the project area are subject to damage from natural processes, visitation, and periodic 

NPS road and trail maintenance. In addition, upgrades to the transportation infrastructure of Ash 

Meadows NWR are being planned. These plans include the following elements that would 

impact vegetation in the project area: 

• A new wayside interpretive kiosk on the southern edge of Devils Hole, with a minimal 

primitive parking area. Construction of the wayside would cause impacts through the 

removal of plants in the area of construction introduction of exotic plants. 

• The Desert Refuge complex has undertaken a transportation survey that will provide 

recommendations for improvements to the existing network of roads and parking lots and 

address transportation, management, maintenance, and coordination threats and challenges 

faced by the Refuge (Ash Meadows, 2007). The goal of these improvements is to enhance 

visitor safety and to support the resource protection mission and policies of the NWR. 

Transportation improvements could increase visitation to Devils Hole and result in additional 

impacts to vegetation caused by visitors walking off-trail and introduction of exotic plants. 

There would be long-term, minor, direct adverse cumulative effects on vegetation from past, 

present, and foreseeable future actions. The No Action Alternative would contribute negligible 

adverse cumulative impacts on vegetation. 
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Conclusion

Researcher visits to monitor conditions in the cavern would continue to cause long-term, 

negligible, direct adverse impacts to vegetation along the access route into the cavern. There 

would be short-term, negligible, local, direct adverse impacts to the vegetation as a result of the 

No Action Alternative due to continued cyclic maintenance of the access road and trails and offtrail hiking. 

The level of impact on vegetation would not result in impairment of park resources that fulfill the 

specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 

4.2.1.4 Wildlife 

Impacts Analysis

As there would not be any new actions under the No Action Alternative, there would not be any 

new impacts on wildlife or wildlife habitat. There would not be additional human activity in the 

area for construction activities, so wildlife would not be affected beyond current disturbance 

from regular vehicle traffic and visitation. Cyclic maintenance activities, visitation, and 

monitoring activities that would continue periodically under this alternative would have 

temporary adverse impacts on wildlife as animals would be disturbed or displaced during human 

activity. 

Cumulative Impacts

Wildlife in the project area is subject to disturbance and damage from natural processes, visitor 

access, monitoring activities, road maintenance, and traffic. There would be continued adverse 

effects on wildlife from vehicles using the roadway, visitation, and monitoring of conditions in 

the cavern. Vehicles passing along the road, visitors to Devils Hole, and monitoring activities 

cause short- term, local disturbance or displacement of wildlife. 

Upgrades to the transportation infrastructure of Ash Meadows NWR are being planned. These 

plans include the following elements that would impact wildlife in the project area: 

• A new wayside interpretive kiosk on the southern edge of Devils Hole, with a minimal 

primitive parking area. Construction of this wayside would cause temporary displacement of 

wildlife during the construction period. 

• The Desert Refuge complex has undertaken a transportation survey that will provide 

recommendations for improvements to the existing network of roads and parking lots and 

address transportation, management, maintenance, and coordination threats and challenges 

faced by the Refuge (Ash Meadows, 2007). The goal of these improvements is to enhance 

visitor safety and to support the resource protection mission and policies of the NWR. 

Transportation improvements could increase visitation to Devils Hole resulting in impacts to 

wildlife. Effects on wildlife would include mortality, restricted movement, introduction of 
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exotic plants that could affect wildlife habitat, habitat fragmentation and edge effect, and 

increased human access to wildlife habitats. 

There would be long-term, minor, direct adverse cumulative effects on wildlife from past, 

present, and foreseeable future actions. The No Action Alternative would contribute negligible 

adverse cumulative impacts on wildlife. 

Conclusion

There would be short-term, negligible, local, direct adverse impacts to wildlife as a result of the 

No Action Alternative due to vehicles using the roadway, visitation, and monitoring of 

conditions in the cavern. 

The level of impact on wildlife would not result in impairment of park resources that fulfill the 

specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 

4.2.1.5 Threatened & Endangered Species, Candidate Species, and Species of Special 

Concern 

Impacts Analysis

Under the No Action Alternative the survival of Devils Hole pupfish would be jeopardized by 

two factors: 

1. Altered surface runoff and deposition of gravel into the pool caused by the existing fence 

would impact substrate composition on the shallow upper shelf, the principal spawning 

area for pupfish. Lack of suitable substrate would likely reduce pupfish spawning success 

and lead to declines in invertebrate populations, which are the primary food items in the 

pupfish diet. 

2. The existing security system provides inadequate protection from the possibility that 

vandals could harm critical habitat for the pupfish or that visitors could inadvertently 

impact the habitat. 

The Devils Hole riffle beetle and Amargosa tryonia snail would be impacted by the same two 

factors as for the pupfish, which could result in disturbance of their primary habitat and declines 

in populations. Other special status species occurring in the project area are not expected to be 

affected by the No Action Alternative aside from those impacts previously described in the 

wildlife section above. 

Cumulative Impacts

Special status species in the project area are subject to disturbance and damage from natural 

processes, visitor access, monitoring activities, road maintenance, traffic, and declining water 

levels in Devils Hole. There would be continued adverse effects on wildlife from vehicles using 

the roadway, visitation, and monitoring of conditions in the cavern. Vehicles passing along the 
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road, visitors to Devils Hole, and monitoring activities cause short- term, local disturbance or 

displacement to terrestrial wildlife. 

Declining water levels resulting from groundwater pumping in Ash Meadows during the late 

1960’s and early 1970’s dramatically lowered water levels in Devils Hole. Water levels 

recovered once ground water pumping ceased, but since the late 1980’s water levels have again 

steadily declined. The principal threat to the Devils Hole pupfish is water loss. The continued 

survival of Devils Hole pupfish relies on the availability of shallow water on the upper shelf 

where pupfish spawn and where the bulk of the primary productivity that supports the aquatic 

community occurs. 

On September 11, 2004 eighty pupfish, one third of the population, were accidentally killed in an 

incident when traps used to monitor the fish were washed into Devils Hole by a flash flood. 

A number of water related projects that could impact future water levels in Devils Hole are in the 

planning process. 

• The Southern Nevada Water Authority (SNWA) has proposed to develop approximately 

8,000 acre-feet of ground water per year from an area north and northwest of Las Vegas. 

The location would be approximately 35 to 45 miles east and north of Devils Hole. The 

Nevada State Engineer ruled on these water right applications several years ago, however, 

SNWA has chosen to put the project on hold and there is no definitive timeline when it may 

be re-activated. 

• The State of Nevada is considering a water rights petition heard in September 2007 involving 

changes in points of diversion for irrigation pumping in the Amargosa Valley. If those 

change applications are granted, Devils Hole water levels could be affected. 

• The Las Vegas metro and the Amargosa Desert are desirable areas for further development, 

and many projects are proposed for which the State of Nevada could issue water rights. For 

example, a private company is planning a solar array near Crystal, NV, over 50 miles from 

Devils Hole, which would involve groundwater pumping in the Amargosa Valley. The Park 

Service has the right to challenge any award of water rights that it can demonstrate would 

threaten the federal reserved water right for Devils Hole. 

• The Desert National Wildlife Refuge Complex is preparing a Comprehensive Conservation 

Plan/Environmental Impact Statement (CCP/EIS) that includes four refuges: Desert, ASH 

MEADOWS, Pahranagat and Moapa. The CCP/EIS describes the resources, public use, 

goals, objectives, and strategies for ASH MEADOWS and for the other refuges. It also 

identifies potential environmental effects of potential actions under consideration. The 

CCP/EIS effort was started in 2004; the administrative draft has been completed; and the 

final draft is currently being prepared. The CCP may have future beneficial or adverse effects 

on water levels in Devils Hole depending on management decisions made. 

In addition, the likelihood of increases in global temperature that have been predicted over the 

next century (IPCC, 2008) could increase the water temperature of the pool. Any increase in 

water temperature could adversely impact the pupfish, given the evidence that the pupfish may 

already be existing at the upper edge of the temperature range for sustainable spawning and 

recruitment (Shrode and Gerkin, 1997). 
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There would be long-term, major, direct and indirect adverse cumulative impacts on T&E 

species from past, present, and foreseeable future actions. The No Action Alternative would 

contribute major adverse cumulative impacts on T&E species. 

Conclusion

There would be long-term, major, direct and indirect, adverse impacts to the Devils Hole pupfish 

as a result of the No Action Alternative. The existing fence has been identified as contributing to 

habitat alterations that would jeopardize the continued existence of these species by adversely 

modifying critical habitat. 

In addition, increased travel on area roads could increase concentrations of airborne particulate 

matter, decreasing solar energy available to fuel primary production in Devils Hole (Wilson and 

Blinn 2007). 

The level of impact on threatened and endangered species could result in impairment of park 

resources that fulfill the specific purposes identified in the enabling legislation or that are 

essential to the natural or cultural integrity of the park. 

4.2.1.6 Visitor Experience 

Impacts Analysis

The No Action Alternative will not directly change the visitor experience, and it will not be 

likely to change the number or type of visitors to the Devils Hole site. As part of its Visitor 

Services Plan, the Refuge may construct an informational kiosk south of Devils Hole, which 

would provide additional information for visitors. Otherwise, no major changes would be made 

to the convenience or information provided at the site. Without changes, the visitor appeal of the 

site may degrade over time, thereby leading to less public support for the recovery of the pupfish, 

though this impact is likely to be minor and difficult to measure. If, however, the No Action 

were chosen and as a result, the pupfish became extinct, the justification for the security, 

monitoring, and interpretive infrastructure would be mostly lost, and the visitor experience itself 

would most likely cease to exist. This is a potentially major indirect impact. 

Cumulative Impacts

Some of the projects being planned by the Refuge could impact Devils Hole. The interpretive 

kiosk tentatively planned for south of the Hole would enhance visitor education, providing 

positive benefit. If any transportation projects served to significantly increase traffic along 

Devils Hole Road, that could increase visitors to a point where additional parking facilities might 

be needed. The visitor survey planned by USFWS could be used to make improvements 

elsewhere on the Refuge--at the Visitor Center, for example-- that could ultimately provide 

indirect benefit to visitors to Devils Hole. Other specific projects are insufficiently mature to 

analyze potential impacts, but given the mission to protect natural resources within the Refuge, it 
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is unlikely that any projects that could cause cumulative impacts to the pupfish would move 

forward without sufficient mitigation. 

Conclusion

Overall, adverse, major, long-term impacts to the visitor experience may result from the 

implementation of the No Action Alternative, given that the habitat conditions that sustain the 

very basis of the visitor experience would continue to degrade. 

4.2.1.7 Park Operations 

Impacts Analysis

Under the No Action Alternative, no improvements to the security of the site, and no 

improvements to the convenience and human safety of monitoring activities, would be made. 

This would lead to the same or increased levels of vandalism or breaches of the security fence, in 

turn leading to the same mostly ineffective, after-the-fact security responses by Law 

Enforcement staff. Over time, as those with malicious intent became aware that the Park had 

declined to enhance site security, malicious attacks could increase, further stressing the fence 

structure and the security response system, which would invite further attacks in a vicious cycle. 

This could produce a moderate impact. 

With respect to human safety, researchers would continue to use the makeshift access ladder and 

monitoring platform to conduct their routine activities. It is not possible to predict whether 

serious injury or accidents will occur, only that the likelihood of them will not decrease without 

further action. The probability of such an accident increases over time. Any injury accidents 

that occurred after the Park chose the No Action Alternative would be defined as a moderate 

impact. 

Cumulative Impacts

The potential water projects in the cumulative scenario will not contribute to cumulative impacts 

from the No Action Alternative to site security or researcher safety, and thus Park operations. 

Being so distant from the site, any of those projects, if implemented, would not impinge on the 

site area directly, and so would not compromise or enhance the security infrastructure of the site. 

Their remoteness from the site would also preclude any impact on researcher safety. 

The Refuge planning activities are also not likely to contribute to cumulative impacts of this 

project on Park operations, with one possible exception: if either the transportation projects or 

visitors services projects bring significantly increased traffic to (or past) the site, then this could 

put increased pressure on the security system, simply by increasing the probability of malicious 

attempts. This could further degrade the fragile habitat of the pupfish, and therefore its recovery. 
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Conclusion

Overall, the No Action alternative could produce adverse, moderate, short and long-term impacts 

on Park Operations—specifically, site security—due to continued degradation in the protection 

afforded by the existing fence. 

4.2.1.8 Cultural Resources 

Impacts Analysis

In its current form, the Devils Hole site continues to hold the cultural values that render it a 

Traditional Cultural Property, and it is still used by the Timbisha Shoshone and Pahrump Paiute 

in their traditional manner. The No Action Alternative would not change the ability of the tribes 

to continue their current use, although further degradation of the natural resource values through 

vandalism could occur if none of the proposed additional security measures are taken. 

The No Action Alternative would also not make any improvements to the natural flow of 

sediment into the Hole; therefore, to the extent that the current interference with natural flow 

causes further degradation to the habitat values of the water and contributes to further decline or 

extinction of the pupfish, this could degrade the natural resource values—the uniqueness of the 

groundwater pool--that form the basis of the site’s cultural significance. Direct and indirect 

impacts to water are described in Section 4.2.1 2; these form the basis for any impacts to cultural 

resource values. Overall, adverse, short- and long-term, minor, and localized impacts to Devils 

Hole are likely, due to the potential for researchers using the makeshift system of descent to the 

Hole and the existing monitoring platform to inadvertently cause cliff sediments to loosen and 

wash into Devils Hole. Additional impacts would be possible from visitors going off-trail, 

displacing vegetation and increasing the potential for soil erosion into the water. 

Thus, to the extent that the No Action Alternative leads to an increased likelihood of vandalism, 

a degradation in pupfish habitat, and no increase in public awareness or support for protection, it 

threatens the cultural values that underlie the site, and could therefore lead to adverse impacts. 

Cumulative Impacts

Possible groundwater pumping projects mentioned in the Cumulative Scenario (Section 4.1 ) that 

jeopardize the water level in the Hole also jeopardize the cultural resources associated with it, 

because the cultural significance is tied to the presence of the unique waterbody. It is likely that 

these projects would be challenged if the Park felt they would cause significant impacts to the 

water level in the Hole. To the extent that No Action contributes to the further deterioration of 

the integrity of the natural systems that support a healthy water level, its cumulative impact on 

the cultural resource values could be major. 
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Conclusion

Overall, adverse, major, long-term impacts to cultural resource values may result from the 

implementation of the No Action Alternative, given that the habitat conditions that sustain the 

very basis of its cultural value would continue to degrade. For this reason, the Timbisha 

Shoshone Tribe have expressed their ultimate preference that no action to be taken at Devils 

Hole, although they will support Alternative A. 
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4.2.2 Alternative A 

4.2.2.1 Soils and Geology 

Impacts Analysis

Fenceline 

Soil disturbance is defined as anything that causes the impairment of physical, chemical and 

biological properties and processes, such as erosion, compaction, displacement, rutting, burning, 

loss of organic matter and mass movement of soil (Deluca, 2001; USDA-ARS, 2005). Soils 

would be disturbed during fenceline and floodgate installation. This would require the use of 

heavy machinery to clear and level the land the fence will be built on, the permanent 

displacement of soils for the installation of fence posts, as well as a slight alteration in drainage 

and soils movements. Construction equipment has the potential to compact soil, reducing 

porosity and conductivity. Such compaction is likely to slightly increase the amount of surface 

runoff in the immediate area. 

Construction equipment to be used during the various facets of site development would include 

pick-up truck or Bobcat on tracks and a large posthole drill, probably run off the Bobcat. As 

with almost any construction project involving the use of heavy equipment, there is some risk of 

an accidental fuel or chemical spill, and the potential contamination of soils. Further, there is the 

risk of these contaminated soils running off into any nearby surface water. The soils types in and 

around Devils Hole (see Section 3.1) are well-drained and gravelly with low to medium runoff 

capabilities. Disturbance of these soils is not likely to cause high levels of runoff as stormwater 

will likely infiltrate. However, vegetative cover is sparse and the topography is steep; both of 

these traits can lead to an increase in stormwater runoff in the event of a heavy rainfall. In order 

to reduce the potential for soil contamination and erosion during construction activities, the 

BMPs described in Chapter 2 will be applied. Soils that are displaced for the installation of the 

fence posts will be properly disposed of if they contain any of the fuels or oils discussed above, 

or, if clean, re-introduced during the Habitat Restoration activities (see below) after construction 

is completed. 

Once operational, the new fenceline will likely be an improvement over current drainage which 

is closer in to Devils Hole and therefore does not allow sediment to migrate as it would naturally. 

The placement of the new fenceline further away from the Hole will allow for sediment to move 

naturally. Any soils that may have migrated during the construction period will stabilize once 

the fenceline is fully installed. Permanent soils displacement and compaction can be expected to 

occur as a result of the installation of the fence posts, which require poured concrete in place of 

soils. Some permanent soil compaction can be expected to result from the use of heavy vehicles 

and machinery in the vicinity of the Hole. In addition, minor compaction will result from 

installation of the floodgate. While relocating the fence further from the Hole improves natural 

drainage, having a fence inside the natural flow of the watershed still constrains natural flow 

somewhat, requiring the use of the floodgate to allow sediment and nutrient flows into the Hole. 

Concentration of flows through the floodgate without a concrete spillway will increase erosion of 

topsoil in the drainage pathway below the floodgate. 
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Visitors Platform, Access, & Interpretation 

Impacts to soils from the installation of the visitors tunnel fencing and removal of the gate below 

it can be expected to be similar as those discussed above under the fenceline installation. The 

same types of soils will be disturbed with similar equipment for the duration of construction 

activities. Some rock and soil deposition into the Hole from removal of the platform is likely to 

occur, and the same BMPs would be applied. If these measures are taken, impacts will remain 

minor. 

Soils will be permanently displaced and likely compacted during the construction of the fenced 

tunnel over the existing access trail leading to the visitors platform, as well as the installation of 

the posts to support the tunnel fencing. The total area of disturbance will be less than 500 square 

feet. Any displaced soils will be handled as discussed above. 

Access Ladder 

Installation of the “ships ladder” will result in similar impacts to soils as discussed above. These 

impacts will mostly be in the form of compaction due to the use of a small crane and scaffolding 

during installation. The ladder will require anchors into the rock faces for support. These 

anchors are not expected to impact soils, although the drilling could cause some rock pieces to be 

dislodged and then deposited near or into the Hole. Some permanent compaction may result 

from the crane movement over soils; no other soil impacts from the ladder are expected. As 

described above, construction BMPs would be applied to minimize rock piece deposition, soil 

contamination, erosion, and disturbance. With these preventive measures, soil impacts should 

remain minor and temporary. 

Monitoring Platform & Equipment 

The segmented monitoring platform will be built off-site and stored at the foot of the Devils Hole 

site. No impacts to soils are expected from the repeated assembly and use of the portable 

monitoring platform at Devils Hole. The foot traffic along the soils surrounding the Hole will be 

virtually the same as the No Action alternative, since monitoring will occur at the same 

frequency regardless of which alternative is chosen. 

Drilling the anchor holes at the south end of the water’s edge could cause some rock pieces to be 

dislodged and then deposited into the Hole. This will be minimized by using the smallest 

adequate drill bit, and employing rotary drilling tools that are equipped with dust-catching bags 

and internal fan. 

The presence of the operational monitoring platform is not expected to impact soils. 

As described in Section 2.2.1, in this alternative the entire stilling well and frame structure will 

be removed and the Park will rely on pressure transducers and a new staff gage (the existing staff 

gage is connected to the stilling well) to measure water level. The Park will attempt to use 

existing anchors to affix the new staff gage in a location along the east wall that is easily 
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accessible from the south shore, but it may be necessary to install two new anchor bolts in the 

east wall as necessary. As with all drilling activities, the impacts from vibration and deposition 

will be minimized by using the smallest adequate drill bit, and employing rotary drilling tools 

that are equipped with dust-catching bags and internal fan. 

Security System 

The security system upgrades under Alternative A would require temporary land disturbance 

around the areas of the existing tower and location of the additional security cameras. Small 

areas of soils would be disturbed for the installation of the buried cables; these soils would be 

disturbed and compacted for the length of time the cable is in the ground. As described above, 

construction BMPs would be applied to minimized soil contamination, erosion, and disturbance. 

Installing higher end video cameras would cause minor disturbance of the area around the tower 

to replace and re-wire cameras #1 and #2. Installing the cameras in the crevasse (#3 on the cliff 

and #4 in the cavern) would involve drilling into the cliff face and the cavern ceiling to mount 

the camera supports, and extending buried cable from the solar power inverter to the camera 

mount. Installing camera #5 on the visitors platform would require installing a mounting post 

and routing cable as well. The Park will conduct vibration testing on the rocks by drilling a 

single hole into the rock in which holes will be drilled and measuring and observing vibration. 

The largest rock sizes feasible should be used to minimize transmitted vibration to the hole. In 

addition, using the minimum size of drill bit adequate for the camera mount will minimize 

vibration. 

Communications Infrastructure 

Impacts from the installation of the satellite or microwave dish and fiber optic cables can be 

expected to be minor and short-term, the same as those discussed above under the fenceline. The 

placement of these components can be expected to permanently displace soils in the immediate 

area and along the 100’ of ground where the cable would be buried. No operational impacts can 

be expected. 

Power Supply 

The solar panel frame will be mounted on six 2-1/2" or 3" diameter posts, with three posts 

located at the center and on either end on the upper and lower areas of the frame. Posts will be 

anchored in concrete footings, approximately 2’ diameter and 3’ deep (to be determined by the 

solar panel vendor during final design). 

Impacts from the construction of the solar array required under this alternative can be expected 

to be similar as those discussed above under Fenceline. Construction equipment and the 

installation of the 300 square feet of photovoltaic cells are likely to result in permanent soils 

compaction and displacement. As described above, construction BMPs would be applied to 

minimized soil contamination, erosion, and disturbance. 
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Site Revegetation 

Watering and planting of native vegetation as in Alternative A will aid in the formation of stable, 

permeable, and infiltrative soils that will help support a healthy ecosystem. The higher ground 

cover in native and semi-native vegetation results in less loss of topsoil. Established natural 

communities are also better able to resist invasions by alien plant species. So the use of native 

plants can help prevent the spread of alien species already present in a region and help avert 

future introductions. 

Cumulative Impacts

Currently, none of the water-related or Refuge planning projects can be expected to impact soil 

resources within the vicinity of Devils Hole. Since each of these projects would exist outside of 

the Devils Hole surface watershed, no soils would be impacted and no changes to sediment 

movement would occur. Additionally, these activities would not influence any of the soils that 

supply nutrients to Devils Hole. However, as the Refuge improvement projects are planned in 

more detail, specific measures would be taken to ensure that they do not jeopardize or adversely 

affect critical habitat for the DH pupfish. This would include considering any project 

components that would alter soil movement in and around Devils Hole. Alternative A would not 

contribute to cumulative impacts from the scenario described above. 

Conclusion 

Overall impacts to soils from the implementation of Alternative A can be expected to be partly 

adverse and partly beneficial, minor, both short- and long-term, and cover a medium sized area 

around the project site. Some impacts, such as compaction due to construction and installation 

activities will be short-term, while the installation of poured concrete for fence posts will be 

long-term. Mitigation measures that will be required to offset these impacts include the 

implementation of BMPs to decrease erosion, as well as habitat restoration techniques. Adverse 

impacts to soils will result from the installation of project components (fencing, additional 

camera locations, the solar array, etc.) that permanently displace soils. In addition, erosion 

would occur from the use of the floodgate to focus drainage down an exposed pathway. 

Beneficial impacts can be expected to result from the construction of a safe and protected trail 

and more secure fencing. These components of the project will help to ensure that visitors stay 

in approved areas and avoid going off-trail which can lead to additional soil compaction and 

erosion over time. The cumulative effects on soils from other past, present, and reasonably 

foreseeable projects, in conjunction with Alternative A, would be negligible.

The level of impact on soil resources would not result in impairment of park resources that fulfill 

the specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 
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4.2.2.2 Water 

Groundwater

Impacts Analysis 

Fenceline

The installation of the fenceline under Alternative A will result in soil compaction, disruption, 

and potential erosion as discussed under Section 4.2.2.1. These impacts could affect 

groundwater if any sediment, fuels, or oils reach area aquifers through Devils Hole. If sediment 

erodes into Devils Hole, it could cloud the surface of the water, blocking sunlight, increasing the 

water temperature, and altering the levels of dissolved oxygen (DO). Additionally, fuels and oils 

could potentially contaminate the water found within Devils Hole. Since the Hole is directly 

connected to groundwater, these impacts could extend to nearby aquifers as the water travels. 

The risk of this occurring during fenceline installation is minimal due to the majority of the 

fenceline being sufficiently remote from the Hole, and potential contaminants are not likely to be 

substantial enough to travel far within a given aquifer. No changes in groundwater level are 

expected to result from the fenceline installation. BMPs will be utilized throughout construction 

to minimize sediment or potential fuel leaks or spills from migrating throughout the construction 

site. If any potential contaminants do reach groundwater, they can be expected to dissipate, 

especially once construction activities are finished. The depths to which fence posts will be 

installed (two feet) are not expected to be enough to reach groundwater. Since the fencing would 

be located where springs are not reaching the surface, it can be assumed the groundwater is far 

enough below the surface to not be impacted by construction. 

Once the fence is fully installed and operated, it would not be expected to influence groundwater 

quality or movement, because it would be sufficiently separated from any groundwater. Further, 

this new fenceline will encompass a larger land area than the existing fence, allowing for an 

improvement in surface drainage and infiltration rates. The improved natural drainage is likely 

to help maintain groundwater quality, nutrient levels and temperature. 

Visitors Platform, Access, & Interpretation 

As described above under the impacts of fenceline installation, erosion and runoff caused by 

construction of the fenced tunnel to the visitors platform, enclosure of the platform, and removal 

of the fencegate below should not impact groundwater quality. However, if significant rock and 

sediment were deposited into the Hole at an above-normal rate, it could increase water 

temperature as these materials absorb solar energy. The risk of this occurring during the 

enclosure of the visitors platform and the trail would most likely be slightly greater than during 

the installation of the fencing due to its location closer to Devils Hole. If this were to occur, 

some of the impact would likely dissipate after construction activities end as sediment particles 

settle onto substrate. Trail construction would result in loose sediments but they would be 

unlikely to reach groundwater. Throughout this process, BMPs would be implemented in order 

to limit sediment movement and any accidental fuel spills from equipment to the maximum 

extent possible, at both the platform and trail construction sites. Once installed, the enclosure to 
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the visitors platform and trail are not likely to impact groundwater. As with the fenceline, these 

facilities are likely to have a beneficial impact on groundwater quality in this area. By limiting 

visitors to areas within the enclosures, these facilities will protect both Devils Hole and its 

surrounding groundwater from detrimental impacts. 

Access Ladder

The potential impacts to groundwater from the installation of the ships ladder would come from 

the risk of contamination from sediment, construction waste, and equipment fuel migrating into 

groundwater at the project site. Construction equipment and activities and their impacts on soil 

movement and compaction for the ladder are described in Section 4.2.2.1. The risk of 

groundwater contamination from the installation of the ladder is low. The proximity of the 

proposed ladder to the surface of Devils Hole increases the risk of eroded sediments reaching the 

water. Additionally, chipping rocks and drilling anchors into the cliff while working directly on 

the steep slopes would increase the risk of sediments, concrete, and rocks entering Devils Hole. 

The BMP requirements discussed in Section 2.5 will aid in sediment control and further limit this 

risk. These impacts would most likely dissipate once construction is complete. 

Once the ladder is constructed and installed, no impacts to groundwater can be expected. The 

addition of the ladder will aid directly to the protection of natural resources at the Devils Hole 

site, because allowing researchers safe access to the Hole will prevent the need to drag temporary 

ladders in and out of the site, which can lead to erosion. 

Monitoring Platform & Equipment 

As with the access ladder, any potential impacts to groundwater with the installation of a 

sectional removable monitoring platform would come from the migration of sediment and 

equipment fuels into Devils Hole. The types of groundwater quality and temperature-related 

impacts would be the same as described above under the other project components. The level of 

risk of these impacts occurring would be slightly greater than under the installation of the ladder 

due to the very close proximity of the installation area to Devils Hole. Segments of the platform 

will be lowered to their sites and anchored in. Loose rocks and sediment from workers and 

drilling would have the potential to reach the surface of Devils Hole and migrated into nearby 

aquifers. BMPs will be applied to help mitigate against the potential contamination from 

sediment movement. Once installed, the monitoring platform is not expected to impact 

groundwater quality or movement. Further, safer and permanent access to research locations 

would likely prevent the erosion caused by the movement of temporary platforms in and out of 

the vicinity. 

Security System

The minor ground disturbances required to install the security systems under Alternative A, 

including trenching additional cables and mounting cameras, are not expected to impact 

groundwater quality, movement or temperature. Cable or camera installations would not be 

expected to be deep enough to reach or impact groundwater. Security system operations would 

also not impact groundwater directly; to the extent that security improvements deter breaches of 
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the fenceline, which can lead to disturbance or erosion of sediments into the Hole, groundwater 

features could be enhanced. 

Communications Infrastructure

No impacts to groundwater quality or movement would be expected as a result of the installation 

or operation of communications infrastructure under Alternative A. Digging and burial will not 

reach groundwater. 

Power Supply

Impacts from the construction of the solar array required under this alternative can be expected 

to be similar as those discussed above under Fenceline. Construction equipment and the 

installation of the 300 square feet of photovoltaic cells are likely to result in minor ground 

disturbances, which are not expected to reach or impact groundwater. Cable installation would 

not be expected to be deep enough to reach or impact groundwater. Operations would not 

impact groundwater quality or movement. 

Site revegetation 

Site revegetation techniques under Alternative A are not likely to have more than a negligible 

though beneficial impact on groundwater within the vicinity of Devils Hole. The establishment 

of a native vegetative community would help restore natural drainage and infiltration rates which 

could benefit groundwater. Steady and natural levels of infiltration via healthy soils would help 

maintain groundwater quality and temperature. Nutrient and dissolved solids levels would most 

likely fluctuate within normal limits within a healthy ecosystem over time. 

Cumulative Impacts 

There have been major, direct and indirect adverse cumulative impacts to the water level in 

Devils Hole from past groundwater pumping activities. Each of the proposed water-related 

development projects described in the cumulative scenario has the potential to change 

groundwater levels and flow rates within the regional aquifer that includes Devils Hole. As 

discussed in Section 3.2, the underlying hydrogeology of this entire region is heterogeneous and 

mostly unknown. The specific interaction of proposed groundwater use activities and 

groundwater level and quality in Devils Hole is difficult to quantify within the scope of this EA. 

Any groundwater pumping within the approximately 22,000 preserved acres surrounding the 

Hole is most likely to impact groundwater within Devils Hole. But this is unlikely to occur. 

Each of these proposed projects would occur outside of this protected groundwater region; 

however, given the unknown hydrogeologic connections in this region, changes in water level in 

Devils Hole could occur. 

Refuge planning projects as they are currently described in the cumulative scenario are not likely 

to impact groundwater in or around Devils Hole; when more detailed information and planning 

has been completed, a more accurate assessment of the potential impacts can be made. 
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Since the implementation of Alternative A would have only short-term adverse impacts on 

groundwater but long-term beneficial impacts to the overall hydrology of the region by allowing 

more natural drainage, no changes to groundwater levels within Devils Hole are expected to 

result from the implementation of Alternative A. Because of this, Alternative A is unlikely to 

contribute to the cumulative effects described above. 

Conclusion 

Overall impacts to water from the implementation of Alternative A can be expected to be partly 

adverse and minor in the short-term, and beneficial and minor in the long-term, and covering a 

medium-sized area around the project site. Adverse short-term impacts include potential 

contamination and decreased infiltration due to construction and installation activities. 

Mitigation measures that will be required to offset adverse impacts include the implementation 

of BMPs to minimize deposition of rock material from drilling into the cliff and to decrease 

erosion, as well as habitat restoration techniques. Beneficial impacts can be expected to result 

from the construction of a secure accessible trail and secure fencing. These components of the 

project will help to ensure that visitors stay in approved areas and avoid going off-trail which can 

lead to additional soil compaction and changes in infiltration over time. The cumulative effects 

on groundwater from other past, present, and reasonably foreseeable projects, in conjunction 

with Alternative A, could be expected to be adverse, moderate, long-term, and project area-wide, 

but virtually none of these effects would be attributable to Alternative A itself. The level of 

impact on groundwater resources would not result in impairment of park resources that fulfill the 

specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 

Surface Water

Impacts Analysis 

Fenceline

Impacts to surface water from the installation of the fenceline per Alternative A can be expected 

to result from the potential erosion of soils and any fuel spills or leaks from construction 

equipment. As discussed in Section 4.2.2.1 and above in the groundwater impacts analysis, soil 

compaction, disturbance, the removal of vegetation and the use of heavy machinery that requires 

fuel and oils all have the potential to impact surface water. The risk of potentially contaminated 

sediments eroding into Devils Hole from the fenceline installation is small. However, if it were 

to occur, these sediments could cloud the upper reaches of the Hole, absorbing sunlight, 

increasing water temperature and decreasing DO and primary productivity. This would likely be 

temporary. Any contaminants, fuels or oils used in construction equipment that might reach the 

Hole would not likely be water-soluble and would therefore most likely pass through the fish 

habitat after some time. Although they could impair water quality, it would be for only a short 

period of time. These potential risks from sediment eroding into Devils Hole are not likely to 

alter the chemical makeup or nutrient balance of this small body of surface water for a time 

period any longer than the duration of construction. No changes in water level in Devils Hole 

would be expected due to fenceline installation. The fenceline in this alternative will not be 
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constructed near any surface water bodies, with the exception of the south side of Devils Hole 

itself. While the potential for sediment and other contaminant movement into Devils Hole exists, 

the implementation of BMPs should help mitigate these risks. Once construction has been 

completed, the fenceline will allow for more natural migration of sediment as well as surface 

drainage to resume in the area surrounding Devils Hole. This will aid in protecting surface water 

quality, temperature and overall chemistry by restoring natural sediment fluctuations and 

infiltration rates. 

Visitors Platform, Access, & Interpretation

Similar impacts to water quality, chemistry and temperature as described above under the 

fenceline could result from the installation of the enclosed visitors tunnel along the trail to the 

visitors platform, removal of the fencegate below, and the fenced enclosure of the platform itself. 

The removal of vegetation, work on steep slopes, soil compaction and disturbance, and the use of 

machinery requiring fuel and oils can all lead to the potential for contaminated runoff to Devils 

Hole. As the construction for fenced trail and platform enclosure will be done in closer 

proximity to the Hole than the majority of the fence, this risk is greater than for the fenceline as 

presented above. The enclosure of the visitors platform and the construction of the access trail 

will result in soil compaction, disturbance and therefore minor changes in surface drainage. 

However, it is likely that any impacts or contamination would only last for the duration of the 

construction. The fencing that encloses the platform will prevent visitors from throwing rocks or 

other debris down the slope towards the Hole, which will further prevent erosion and potential 

surface water damage. The implementation of BMPs throughout the course of construction as 

well as habitat restoration efforts once the project is complete will lessen the overall impacts to 

surface water. Limiting visitor access to the fenced trail will also prevent visitors from going 

off-trail, thus avoiding additional erosion. No components of construction will occur near any 

surface water bodies aside from Devils Hole. 

Access Ladder

The installation of the access ladder on the slope of Devils Hole would require multiple anchors 

to bolt the structural steel support tubing into both sides of the cliff. Risks to water quality 

would be similar to those described above under construction of the fenced access, as these 

components both require work within the slope environment surrounding Devils Hole. As with 

the fenceline and platform enclosure, the water within Devils Hole could receive eroded 

sediments and these sediments would possibly contain fuels and oils from construction 

machinery. Sediment landing in the Hole could result in a temperature increase as described 

above. In addition, rock pieces could be dislodged by drilling of anchor holes and tumble 

towards or into the Hole. BMPs described in Section 2.5 would be implemented and special care 

would be taken to minimize, to the maximum extent possible, the risks from rock piece and 

sediment runoff. Once in place, the access ladder is not expected to impact surface water quality 

or drainage. The addition of this ladder would likely aid in the protection of the water within 

Devils Hole as it would eliminate the need for researchers to place an access ladder in and out of 

the Hole, which has the potential to cause erosion each time it is done. 
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Monitoring Platform & Equipment 

The installation of the monitoring platform can be expected to add similar impacts to surface 

water quality and drainage as those discussed above under the access ladder due to the close 

proximity of the platform to the surface of Devils Hole. The same types of potential impacts 

from rock fragments falling into the Hole to water quality and temperature could occur due to 

construction within the slopes and near the water surface of Devils Hole in order to install the 

anchors for the permanent platform. If the platform is used and maintained as planned, no 

operational impacts to Devils Hole can be expected. As with the project components discussed 

above, the addition of a safer, permanent monitoring platform will likely help protect the water 

within Devils Hole by allowing researchers to not have to move a platform in and out of the Hole 

area. 

Security System

The construction activities required to install the security system upgrades in the upland areas 

around Devils Hole are not expected to result in more than minor disturbances to land and soils 

in the immediate area. These minor disturbances would result in loose soils that could be 

potentially contaminated with the fuels and oils used in the construction machinery. There 

would be a small risk of these soils eroding into Devils Hole, but the distance from the Hole and 

the small size of impact would not likely lead to more than negligible impacts. 

Installing the cameras in the crevasse (#3 on the cliff and #4 in the cavern) would involve 

drilling into the cliff face and the cavern ceiling to mount the camera supports, and extending 

buried cable from the solar power inverter to the camera mount. Installing camera #5 on the 

visitors platform would require installing a mounting post and routing cable as well. Again, the 

potential exists for depositing rock and dislodging soil that would enter the cavepool below, 

potentially impacting water temperature and quality. These impacts would be minimized by 

drilling into the largest rock sizes feasible and using the minimum size drill bit adequate for the 

size of the camera mount. Camera #6 is an underwater camera. 

No impacts to Devils Hole or other surface water bodies are expected from the operation of the 

upgraded security system components. Repairs to the cameras in sensitive locations would be 

done with precautions similar to those taken during normal monitoring operations. 

Communications Infrastructure

No impacts to surface water would be expected as a result of the installation of the satellite or 

microwave dish or laying of buried cables. Installation and burial of cables will be done at such 

distance from the Hole and with proper BMPs so that the risk of delivering contaminants and 

sediments into the pool are minimized. Operation of communications infrastructure under 

Alternative A is expected to have no impact on surface water. 
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Power Supply

The ground disturbances required to install the power supply under Alternative A are not 

expected to reach or impact surface water. Operations of the solar array to generate and 

distribute electricity would also not impact surface water. 

Site revegetation

Site revegetation under Alternative A would help restore natural drainage and improve soil 

retention which can limit the potential for sediment runoff into Devils Hole. Helping to restore 

natural sediment flow and infiltration rates will ensure that Devils Hole is receiving natural 

levels of sediment and water. This would help maintain appropriate nutrient levels and water 

temperatures that could be expected to fluctuate within normal limits for the region. Overall 

impacts would be beneficial. 

Cumulative Impacts 

There have been major, direct and indirect adverse cumulative impacts to the water level in 

Devils Hole from past groundwater pumping activities. Each of the proposed water-related 

development projects described in the cumulative scenario has the potential to change 

groundwater levels and flow rates within the regional aquifer that includes Devils Hole. Lower 

groundwater levels within the regional karst aquifers could lead to changes in water chemistry. 

These changes may include an increase in the dissolution of calcium carbonate as less water 

travels through the same aquifer conduits. Water temperature in Devils Hole would likely 

increase with a decline in water levels. Sunlight would reach further into the Hole and the 

location of the photic zone would shift as water levels declined over time. General regional 

groundwater withdraw also would have the potential to impact levels of some of the springs 

within the vicinity of AMNWR. 

Refuge planning projects as they are currently described in the cumulative scenario are not likely 

to impact surface water in or around Devils Hole. Since the implementation of Alternative A 

would have only short-term adverse impacts on surface water but long-term beneficial impacts to 

the overall hydrology of the region, no changes to water levels within Devils Hole are expected 

to result from the implementation of Alternative A. Because of this, Alternative A is unlikely to 

contribute to the cumulative effects described above. 

In addition, the likelihood of increases in global temperature that have been predicted over the 

next century could increase the water temperature of the pool (IPCC, 2008). Any increase in 

water temperature could adversely impact the pupfish, given the evidence that the pupfish may 

already be existing at the upper edge of the temperature range for sustainable spawning and 

recruitment (Shrode and Gerkin, 1997). 

Conclusion 

Overall impacts to surface water from the implementation of Alternative A can be expected to be 

partly adverse and partly beneficial, minor, short-term, and cover a medium sized area around 
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the project site. Adverse impacts, such as potential contamination, runoff, and water quality 

changes due to construction and installation activities will be short-term. Mitigation measures 

that will be required to offset these impacts include the implementation of BMPs to decrease 

erosion, as well as habitat restoration techniques. Beneficial impacts can be expected to result 

from the construction of a secure accessible trail and secure fencing. These components of the 

project will help to ensure that visitors stay in approved areas and avoid going off-trail which can 

lead to additional erosion and deposition of materials into the Hole over time. The cumulative 

effects on surface water from other past, present, and reasonably foreseeable projects in 

conjunction with Alternative A could be expected to be adverse, moderate, long-term, and 

project area-wide. The level of impact on surface water resources would not result in 

impairment of park resources that fulfill the specific purposes identified in the enabling 

legislation or that are essential to the natural or cultural integrity of the park. 

4.2.2.3 Vegetation 

Impacts Analysis

Fenceline 

Construction of approximately 1200 linear feet of fencing under Alternative A would necessitate 

removal of plants located along the path of the fence. Repeated disturbance of vegetation by 

construction vehicles and foot traffic during construction in areas where plants are not cleared 

would also cause damage to plants. Soil compaction as a result of construction activities is likely 

to slightly increase the amount of surface runoff in the immediate area, resulting in erosion and 

subsequent damage to plants. Once construction is complete, plants would reestablish along the 

fenceline and in areas disturbed by construction traffic. Native plant reestablishment would be 

enhanced by reducing soil compaction using habitat restoration techniques described below. 

The fence would exclude herbivore species such as desert bighorn sheep from approximately six 

acres. Release from browsing by these herbivores would alter plant species composition and 

growth. 

Exotic plants or seeds could be brought to the site with construction equipment. New 

introductions could allow for exotic plants to become established and spread, especially in areas 

where the ground is disturbed by construction activities. Exotic plants currently growing in the 

area can also become established and spread on newly disturbed substrates. However, mitigation 

to ensure that imported material does not contain exotic plant material would be implemented. 

Visitors Platform, Access, & Interpretation 

The existing viewing platform would be retained, however, the fencing and gate beneath the 

platform would be removed and the trail to the platform, and the platform itself, would be 

enclosed in a fence tunnel over the existing trail. Additionally, the trail may be shifted to insure 

that the tunnel would not cast a shadow on the water in the pool. Removing fencing and the gate 

and enclosing the platform with fencing could result in trampling and destruction of plants in the 

immediate vicinity of the platform. Shifting the trail and installing the tunnel could necessitate 
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the permanent removal of plants along the route leading to the visitors platform. Repeated 

disturbance of vegetation by construction vehicles and foot traffic during construction and 

deconstruction in areas where plants are not cleared would also cause damage to plants. Once 

construction is complete, plants would reestablish in areas disturbed by construction traffic. 

Native plant reestablishment would be enhanced by reducing soil compaction using habitat 

restoration techniques described below. 

Exotic plants or seeds could be brought to the site with construction equipment. New 

introductions could allow for exotic plants to become established and spread, especially in areas 

where the ground is disturbed by construction activities. Exotic plants currently growing in the 

area can also become established and spread on newly disturbed substrates. However, mitigation 

to ensure that imported material does not contain exotic plant material would be implemented. 

Access Stairway 

Use of a crane for the installation of a new ships ladder would trample plants in the immediate 

vicinity of the hole where the stairway is to be located. Repeated disturbance of vegetation by 

construction vehicles and foot traffic during construction would also cause damage to plants. 

Once construction is complete, plants would reestablish in areas disturbed by construction traffic. 

Native plant reestablishment would be enhanced by plantings and soil compaction would be 

mitigated using habitat restoration techniques described below. 

Monitoring Platform & Equipment 

The monitoring platform will be built off-site and stored at the foot of the Devils Hole site. No 

impacts to vegetation are expected from the initial installation or repeated assembly and use of 

the portable monitoring platform at Devils Hole. 

Security System 

The security system upgrades would require temporary vegetation disturbance in the area of the 

existing tower and for the installation of buried cable for two cameras. The two cameras in the 

crevasse and one suspended in the pool would have a buried cable from the solar power inverter 

to the camera mount, thus also disturbing vegetation where the cable is buried. The fifth camera 

would be installed on the hillside or on the visitors platform. If on the hillside, a mounting 

structure would require removal of vegetation where the structure is placed and the repeated 

disturbance of vegetation by construction vehicles and foot traffic to and from the site. If on the 

platform, vegetation would be disturbed with the installation of a mounting post and routing 

cable. Once installation is complete, plants would reestablish in areas disturbed by construction 

traffic. Native plant reestablishment would be enhanced by plantings and soil compaction would 

be mitigated using habitat restoration techniques described below. 

Exotic plants or seeds could be brought to the site with construction equipment. New 

introductions could allow for exotic plants to become established and spread, especially in areas 

where the ground is disturbed by construction activities. Exotic plants currently growing in the 
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area can also become established and spread on newly disturbed substrates. However, mitigation 

to ensure that imported material does not contain exotic plant material would be implemented. 

Communications Infrastructure 

Installation of an 18" satellite or microwave dish on a 3’ by 3’ concrete pad and 100’ of 

underground fiber optic cables would require removal of vegetation where the concrete is placed 

and along the route of the buried cable. Repeated disturbance of vegetation by construction 

vehicles and foot traffic during construction in areas where plants are not cleared would also 

cause damage to plants. Once installation is complete, plants would reestablish in areas disturbed 

by construction traffic. Native plant reestablishment would be enhanced by plantings and soil 

compaction would be mitigated using habitat restoration techniques described below. 

Exotic plants or seeds could be brought to the site with construction equipment. New 

introductions could allow for exotic plants to become established and spread, especially in areas 

where the ground is disturbed by construction activities. Exotic plants currently growing in the 

area can also become established and spread on newly disturbed substrates. However, mitigation 

to ensure that imported material does not contain exotic plant material would be implemented. 

Power Supply 

Installation of 300 square feet of solar panels, battery charging system, and power conditioning 

equipment would require the permanent removal of plants in the immediate area of the panels. 

Repeated disturbance of vegetation by construction vehicles and foot traffic during construction 

in areas where plants are not cleared would also cause damage to plants. Once construction is 

complete, plants would reestablish in areas disturbed by construction traffic. Native plant 

reestablishment would be enhanced by plantings and soil compaction would be mitigated using 

habitat restoration techniques described below. 

Over time, vegetation would need to be pruned or removed as new growth would shade or 

interfere with the solar array. 

Exotic plants or seeds could be brought to the site on construction equipment. New introductions 

could allow for exotic plants to become established and spread, especially in areas where the 

ground is disturbed by construction activities. Exotic plants currently growing in the area can 

also become established and spread on newly disturbed substrates. However, mitigation to ensure 

that imported material does not contain exotic plant material would be implemented. 

Site revegetation 

Overall impacts from Alternative A revegetation are likely to be beneficial. Replanting with 

native plant species would reduce the probability of erosion and establishment of exotic plants in 

the treated areas. 
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Cumulative Impacts

Plants in the project area are subject to damage from natural processes, visitation, and periodic 

NPS road and trail maintenance. In addition, upgrades to the transportation infrastructure of Ash 

Meadows NWR are being planned. These plans include the following elements that would 

impact vegetation in the project area: 

• A new wayside interpretive kiosk on the southern edge of Devils Hole, with a minimal 

primitive parking area. Construction of the wayside would cause impacts through the 

removal of plants in the area of construction introduction of exotic plants. 

• The Desert Refuge complex has undertaken a transportation survey that will provide 

recommendations for improvements to the existing network of roads and parking lots and 

address transportation, management, maintenance, and coordination threats and challenges 

faced by the Refuge (Ash Meadows, 2007). The goal of these improvements is to enhance 

visitor safety and to support the resource protection mission and policies of the NWR. 

Transportation improvements could increase visitation to Devils Hole and result in additional 

impacts to vegetation caused by visitors walking off-trail and introduction of exotic plants. 

There would be long-term, minor, direct adverse cumulative effects on vegetation from past, 

present, and foreseeable future actions. Alternative A would contribute negligible adverse 

cumulative impacts on vegetation. 

Conclusion

Alternative A would result in both adverse and beneficial short and long term, minor, localized 

impacts on vegetation from construction activities and the installation of new facilities. Shortterm adverse impacts would primarily result from damage to plants from construction traffic and 

activities. Long-term adverse impacts would primarily occur where plants are permanently 

removed for fencing, visitor access trail, camera mount, satellite or microwave dish, and solar 

array. Beneficial impacts would result from habitat restoration. 

The level of impact on vegetation would not result in impairment of park resources that fulfill the 

specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 

4.2.2.4 Wildlife 

Impacts Analysis

Fenceline 

Construction activities for installation of approximately 1200 linear feet of fencing and human 

presence would cause temporary displacement and disturbance of resident wildlife for the 

duration of construction. Species are expected to return to the area after construction is 

completed. Some species, such as desert bighorn sheep, may be prevented from using the 

resources on the project site due to habitat alteration and exclusion by the fence. Approximately 
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six acres would be enclosed within the fence. However, the area surrounding the project site 

supports a large area of similar creosotebush scrubland which would provide appropriate habitat 

for resident wildlife species. 

Visitors Platform, Access, & Interpretation 

Construction activities for removal of the fencing and gate beneath the visitors platform, 

installation of a fenced tunnel over the access trail and platform, and human presence would 

cause temporary displacement and disturbance of resident wildlife for the duration of 

construction. Species are expected to return to the area after construction is completed. 

Construction activities should not take place between April and September to avoid disturbance 

of nesting owls or breeding bats. 

Access Stairway 

Construction activities for installation of an access stairway into Devils Hole and human 

presence would cause temporary displacement and disturbance of resident wildlife for the 

duration of construction. Species are expected to return to the area after construction is 

completed. Construction activities should not take place between April and September to avoid 

disturbance of nesting owls or breeding bats. 

Monitoring Platform & Equipment 

The monitoring platform would be built off-site and stored at the foot of the Devils Hole site and 

assembled as needed. Monitoring activities under this alternative do not differ from those in the 

No Action Alternative, thus no additional impacts to wildlife are expected from the repeated 

assembly and use of the portable monitoring platform at Devils Hole. 

Security System 

Construction activities for installation of security system upgrades and associated human 

presence would cause temporary displacement and disturbance of resident wildlife for the 

duration of construction. Species are expected to return to the area after construction is 

completed. 

Communications Infrastructure 

Installation of an 18" satellite or microwave dish on a 3’ by 3’ concrete pad and 100’ of 

underground fiber optic cables and associated human presence would cause temporary 

displacement and disturbance of resident wildlife for the duration of construction. Species are 

expected to return to the area after construction is completed. 

Power Supply 

Construction activities for installation of the solar array and equipment and associated human 

presence would cause temporary displacement and disturbance of resident wildlife for the 
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duration of construction. Species are expected to return to the area after construction is 

completed. 

Site revegetation 

Habitat restoration activities would cause temporary displacement and disturbance of resident 

wildlife. Species are expected to return to the area after restoration is completed. 

Cumulative Impacts

Wildlife in the project area is subject to disturbance and damage from natural processes, visitor 

access, monitoring activities, road maintenance, and traffic. There would be continued adverse 

effects on wildlife from vehicles using the roadway, visitation, and monitoring of conditions in 

the cavern. Vehicles passing along the road, visitors to Devils Hole, and monitoring activities 

cause short- term, local disturbance or displacement of wildlife. 

Upgrades to the transportation infrastructure of Ash Meadows NWR are being planned. These 

plans include the following elements that would impact wildlife in the project area: 

• A new wayside interpretive kiosk on the southern edge of Devils Hole, with a minimal 

primitive parking area. Construction of this wayside would cause temporary displacement of 

wildlife during the construction period. 

• The Desert Refuge complex has undertaken a transportation survey that will provide 

recommendations for improvements to the existing network of roads and parking lots and 

address transportation, management, maintenance, and coordination threats and challenges 

faced by the Refuge (Ash Meadows, 2007). The goal of these improvements is to enhance 

visitor safety and to support the resource protection mission and policies of the NWR. 

Transportation improvements could increase visitation to Devils Hole resulting in impacts to 

wildlife. Effects on wildlife would include mortality, restricted movement, introduction of 

exotic plants that could affect wildlife habitat, habitat fragmentation and edge effect, and 

increased human access to wildlife habitats. 

There would be long-term, minor, direct adverse cumulative effects on wildlife from past, 

present, and foreseeable future actions. Alternative A would contribute negligible adverse 

cumulative impacts on wildlife. 

Conclusion

There would be short-term and long-term, negligible, and localized adverse impacts to wildlife 

as a result of the actions in Alternative A. Short-term impacts are primarily the result of 

temporary displacement during construction activities. Long-term impacts arise from the 

permanent exclusion of wildlife species such as desert bighorn sheep from the fenced area. 

The level of impact on wildlife would not result in impairment of park resources that fulfill the 

specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 
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4.2.2.5 Threatened & Endangered Species, Candidate Species, and Species of Special 

Concern 

Impacts Analysis

Fenceline 

Removal of the existing fence and construction of new fencing would correct the altered surface 

runoff and deposition of gravel into the pool caused by the existing fence. The new fenceline 

would incorporate a flood gate along the natural drainage pathway to allow substrate 

composition on the shallow upper shelf, the principle spawning area for pupfish to receive the 

natural sediment deposition necessary to maintain critical habitat for this species. 

The riffle beetle and Amargosa snail would also benefit from the corrected surface runoff similar 

to the pupfish. Other special status species occurring in the project area are not expected to be 

affected by construction activities in Alternative A aside from those impacts previously 

described in the wildlife Section above. 

Visitors Platform, Access, & Interpretation 

Removal of the fencing and gate beneath the visitors platform and construction of a fence tunnel 

along the trail and over the platform would have no negative impacts on T&E and special status 

species beyond those described in the wildlife section above. The platform would cast a shadow 

over the water as it does currently, thus it would block the same amount of sunlight into the 

Hole: about 15 minutes a day near the autumnal equinox (September), outside the pupfish 

spawning season (Weiss, 2005b). The fencing that encloses the visitors platform would cause 

some small incremental shadows over the hole as compared to the current platform 

configuration. However, the shadowprint of this fencing would not be opaque, leaving a very 

high proportion of the actual shadowprint still unshaded. Additionally, the fenced tunnel over 

the access trail would be constructed along a path that ensures no additional shadows occur over 

the hole. The small amount of new shadowing would have a small adverse effect on net primary 

productivity. 

The new fenced tunnel over the trail and platform would prevent vandals from harming critical 

habitat for the pupfish or visitors inadvertently impacting the habitat. This tunnel would have 

beneficial impacts on pupfish habitat. 
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Access Stairway 

Construction of an access stairway would cause vibration while drilling into rock for the support 

anchors. Although this vibration would be minimized, there would still be some disturbance due 

to the proximity of pupfish to the cliff face. Construction activities would not take place during 

spawning periods, which typically occur between February and May. There would be no 

additional effects on T&E and special status species beyond those described in the Wildlife 

above. 

Monitoring Platform & Equipment 

Installation of the platform (e.g., drilling holes for handrail and steps) and removal of the stilling 

well and frame structure would potentially elicit stress responses by the pupfish (which would be 

difficult to quantify). Additionally, given the fragility of the fish population, any rock or stone 

that is released directly into the pool during construction could result in direct mortality of 

pupfish. Construction activities would not take place during spawning periods, which typically 

occur between February and May. 

This platform would only be assembled and used temporarily during monitoring activities, thus 

would not be expected to have any impacts on primary productivity caused by shading of the 

pool. 

Removal of the stilling well would have beneficial effects on the pupfish because the Park would 

no longer cause disturbance while conducting monitoring by resting a ladder on the existing 

frame structure. 

Other special status species occurring in the project area are not expected to be affected by the 

monitoring platform aside from those impacts previously described in the wildlife section above. 

Security System 

The existing security system provides inadequate protection from the possibility that vandals 

could harm critical habitat for the pupfish or that visitors could inadvertently impact the habitat. 

The new system would have beneficial effects by providing greater protection to critical habitat 

and the pupfish population at Devils Hole. Installation of the camera mounts would cause 

vibration while drilling into rock. Although every effort would be made to minimize duration 

and magnitude of vibrations, there would still be some disturbance due to the proximity of 

pupfish to the cliff face. Installation of the new security system would have no additional 

impacts on special status species beyond those described in the wildlife section above. 

Communications Infrastructure 

No additional impacts to T&E and special status species are expected from the installation of an 

18" satellite or microwave dish on a 3’ by 3’ concrete pad and 100’ of underground fiber optic 

cables beyond the temporary displacement during active construction described in the wildlife 

section above. 
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Power Supply 

Installation of the new security system would have no additional impacts on T&E and special 

status species beyond those described in the wildlife section above. 

Site revegetation 

No impacts to T&E and special status species are expected from site revegetation activities 

beyond those described in the wildlife section above. 

Cumulative Impacts

Special status species in the project area are subject to disturbance and damage from natural 

processes, visitor access, monitoring activities, road maintenance, traffic, and declining water 

levels in Devils Hole. There would be continued adverse effects on wildlife from vehicles using 

the roadway, visitation, and monitoring of conditions in the cavern. Vehicles passing along the 

road, visitors to Devils Hole, and monitoring activities cause short- term, local disturbance or 

displacement to terrestrial wildlife. 

Declining water levels resulting from groundwater pumping in the late 1960’s and early 1970’s 

dramatically lowered water levels in Devils Hole. Water levels recovered once ground water 

pumping ceased, but since the late 1980’s water levels have again steadily declined. Continued 

Devils Hole pupfish survival is reliant on the structure of its habitat, of which the critical 

characteristic is the availability of shallow water on the upper shelf where pupfish spawn and 

where the bulk of the primary productivity that supports the aquatic community occurs. 

On September 11, 2004 eighty pupfish, one third of the population, were accidentally killed in an 

incident when traps used to monitor the fish were washed into Devils Hole by a flash flood. 

A number of water related projects that could impact future habitat conditions (i.e., water levels) 

for the Devils Hole pupfish are in the planning process (described in Section 4.1). 

• The Southern Nevada Water Authority (SNWA) has proposed to develop approximately 

8,000 acre-feet of ground water per year from an area north and northwest of Las Vegas. 

There is no definitive timeline when this currently dormant project may be re-activated. 

• The State of Nevada is considering a water rights petition heard in September 2007 involving 

changes in points of diversion for irrigation pumping in the Amargosa Valley. If those 

change applications are granted, Devils Hole water levels could be affected. 

• The Las Vegas metro and the Amargosa Desert are desirable areas for further development, 

and many projects are proposed for which the State of Nevada could issue water rights. The 

Park Service has the right to challenge any award of water rights that it can demonstrate 

would threaten the federal reserved water right for Devils Hole. 

• The Desert National Wildlife Refuge Complex is preparing a Comprehensive Conservation 

Plan/Environmental Impact Statement (CCP/EIS) that includes four refuges: Desert, ASH 

MEADOWS, Pahranagat and Moapa. The CCP/EIS describes the resources, public use, 
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goals, objectives, and strategies for ASH MEADOWS and for the other refuges. It also 

identifies potential environmental effects of potential actions under consideration. The CCP 

may have future beneficial or adverse effects on water levels in Devils Hole depending on 

management decisions made. 

Increased travel on area roads could increase concentrations of airborne particulate matter, 

decreasing solar energy available to fuel primary production in Devils Hole (Wilson and Blinn 

2007). 

In addition, the likelihood of increases in global temperature that have been predicted over the 

next century could increase the water temperature of the pool (IPCC, 2008). Any increase in 

water temperature could adversely impact the pupfish, given the evidence that the pupfish may 

already be existing at the upper edge of the temperature range for sustainable spawning and 

recruitment (Shrode and Gerkin, 1997). 

There would be long-term, major, direct and indirect adverse cumulative impacts on T&E 

species from past, present, and foreseeable future actions. Alternative A would contribute 

moderate beneficial cumulative impacts on T&E species. 

Conclusion

There would be long-term, moderate, direct and indirect beneficial impacts and short-term direct 

negligible or minor adverse impacts to the Devils Hole pupfish as a result of the actions under 

Alternative A. Adverse impacts would result from installation of structures at or near the hole 

and some additional shading of the water. The existing fence has been identified as contributing 

to habitat alterations that would jeopardize the continued existence of these species by adversely 

modifying the habitat features on which it depends. Under this alternative, the fence would be 

removed and replaced with one that would allow for more natural sediment flow and renewal of 

habitat on the upper shelf. Additionally, security upgrades would reduce the possibility of 

habitat damage from vandalism. However, the actions under this alternative do not address or 

negate the long-term adverse impacts resulting from declining water levels in Devils Hole. 

The level of impact on T&E and special status species would not result in impairment of park 

resources that fulfill the specific purposes identified in the enabling legislation or that are 

essential to the natural or cultural integrity of the park. 

4.2.2.6 Visitor Experience 

Impacts Analysis

Fenceline 

Visitor access to the Hole will be limited or prohibited during most, if not all, of the fenceline 

construction period. The Park will use a variety of communications tools to notify potential 

visitors of construction. Once the new fence is in place, an ungated opening will provide visitor 

access to the fenced tunnel that leads to the visitors platform. 
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The fenced visitors tunnel and platform, as well as the look and feel of the Twinbar fencing 

around the access trail and platform will create a very different visitor experience than the more 

open access it will be replacing; it restricts free movement around the site and communicates a 

forceful security presence, which some visitors may find off-putting. This is discussed under 

Visitors Platform below. 

Visitors Platform, Access Trail & Interpretation 

The existing visitors platform will be enclosed in fencing, with two small holes cut out for direct 

viewing. The trail leading to the platform will be enclosed in fencing as well, creating a “visitors 

tunnel.” In addition, enhanced interpretive panels will provide greater detail and context on the 

status and ecology of the overall site, and the pupfish itself. The Park believes these changes 

will help protect the natural environment, although they come at some cost to the human one. 

Some return visitors may be disappointed and/or frustrated that their access to the overall site is 

so limited but from the standpoint of the overall experience and interpretation, retaining a direct 

view and providing more information about the pool and its conditions should be a “net neutral” 

impact. In addition, the onsite experience will be complemented and enhanced by interpretive 

exhibits at the Refuge Visitor Center and Death Valley National Park’s Furnace Creek Visitor 

Center which will include live video feeds from the cameras mounted within the crevasse and 

underwater, and a video of a Tribal elder talking about the importance of Devils Hole/Ash 

Meadows. It is difficult to predict with certainty what impact these changes will have on the 

number or frequency of onsite visits. The Park’s interpretive display at the Visitors Center may 

have the simultaneous benefit of increasing awareness of the pupfish while limiting actual onsite 

visits by emphasizing the fragility of habitat and providing alternative viewing opportunities. 

The visitors tunnel to the platform will be conveniently accessible through an ungated opening in 

the fence at the end of a trail from the visitor parking area along the public road. 

The Park anticipates a minor increase in onsite visits, at most, from these improvements to 

interpretation. The benefit will come in the form of increased awareness of those who see the 

exhibits at the Visitors Centers. 

Access Ladder 

The new access ladder will have no direct impact on the visitors experience. It is planned to be 

invisible to the visitor. But to the limited extent that it is visible from outside the fence or atop 

the Visitors Platform, it will further communicate to the visitor the importance of monitoring, 

and the seriousness with which the Park and the Refuge consider the recovery mission for the 

pupfish. 

Monitoring Platform & Equipment 

The monitoring platform will have no direct impact on the visitors experience. It will most 

likely not be visible to visitors, even from the visitors platform. Again, to the limited extent that 

it may be visible from atop the Visitors Platform, it will further communicate to the visitor the 
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importance of monitoring, and the seriousness with which the Park and the Refuge consider the 

recovery mission for the pupfish. 

Security System 

The security improvements—increased detection capability, stronger fencing, improved 

communications—could have a negligible negative impact on the visitor experience, that 

possible impact being the visibility of the increased camera presence. Again, this serves to 

reinforce the importance of protecting the site. The cameras located in the crevasse and 

underwater, in addition to sereing a security function (detecting any disturbance within the 

crevasse), will enhance the visitor experience considerably by providing real-time video of the 

pool and its surroundings to the interpretive displays at Refuge Visitor Center and Death Valley 

National Park’s Furnace Creek Visitor Center. 

Communications Infrastructure 

The use of a dedicated satellite link for internet transmission will enable full-motion video to be 

transmitted through the Internet to the Visitors Center displays. This will be a major 

enhancement in the visitor experience, because it will permit visitors to the Center to see realtime full-motion video of the pupfish “in action” throughout the year. It will supplement the 

interpretive panels as only full-motion video can. In addition, having full-motion video of the 

Hole available through a public “webcam” can increase awareness of the plight of the pupfish to 

“virtual visitors” from around the world and thereby help build public support. 

Power Supply 

Enhancing the solar array to meet the increased power requirements of the new security system 

and cameras will have a no impact on the visitor experience. The array will be located in an 

appropriate location to avoid interfering with visitors enjoyment of the site. 

Site revegetation 

Site revegetation will improve the health of the ecosystem and the visual appeal of the site. A 

healthier ecosystem will ultimately enhance the visitor experience, by improving the 

sustainability of the pupfish habitat and aiding its recovery. 

Cumulative Impacts

Any action taken by governments or private actors that threatens the habitat or survival of the 

pupfish could have a corresponding cumulative impact on the visitor experience. It is technically 

true, however, that because actually seeing the fish itself from the platform is such a rare part of 

the overall Devils Hole experience, any actions that harmed but did not eliminate the fish would 

by themselves not change the experience. In the extreme, only actions that resulted in the 

extinction of the species would impact the visitor experience, by removing the justification for 

the interpretive and security infrastructure in the first place. The Devils Hole pupfish lives a 

precarious existence as a species, and the Park believes it can successfully enforce its federal 
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water rights against actions that would endanger it by lowering the water level in the Hole below 

the mandated level. But if such projects went ahead and ultimately led to loss of the fish 

population, the Park could well decide that the site need no longer be maintained and there 

would likely be no visitor experience. 

Some of the projects being planned by the Refuge could impact Devils Hole. The interpretive 

kiosk tentatively planned for south of the Hole would enhance visitor education, providing 

positive benefit. If any transportation projects served to significantly increase traffic along 

Devils Hole Road, visitor traffic could increase to a point where additional parking facilities 

might be needed. The visitors survey planned by USFWS could be used to make improvements 

elsewhere on the Refuge--at the Visitor Center, for example-- that could ultimately benefit the 

visitors to Devils Hole. Other specific projects are insufficiently mature to analyze potential 

impacts, but given the mission to protect natural resources within the Refuge, it is unlikely that 

any projects that could cause cumulative impacts to the pupfish would move forward without 

sufficient mitigation. 

Conclusion

Overall impacts to the visitor experience from the implementation of Alternative A can be 

expected to be both adverse and beneficial, minor, and long-term. While visitors might find the 

new restrictions on access incongruent with the openness of the landscape, the actual experience 

of the site itself from the viewing platform will be enhanced by the addition of improved 

interpretive material. The onsite experience will be complemented by offsite exhibits at the 

Visitor Center and Death Valley National Park’s Furnace Creek Visitor Center , which will 

display video images from within the crevasse and underwater. The additional security provided 

by the security infrastructure will improve the sustainability of the site, and therefore the visitor 

experience, over time. 

4.2.2.7 Park Operations 

Impacts Analysis

Fenceline 

The replacement of the compromised cyclone fence with strategically located Twinbar fencing 

will have a beneficial short- and long-term impact on site security. Twinbar fencing is more 

difficult to cut, and its double-angled tops will make it much more difficult to scale. The fence 

could therefore play an important role in the overall strategy of deterring malicious entry into the 

site. 

The fence would have no direct impact on the safety of staff when they conduct monitoring 

operations at the site. To the extent that improvements in site security further reduce the danger 

that the area around the cliff would become unstable and further endanger staff access, this could 

produce a beneficial indirect impact. 
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Visitors Platform, Access, & Interpretation 

The enclosure of the visitors platform and construction of the new enclosed access trail would 

have no direct or indirect impacts on site security or researcher safety. Monitoring staff would 

use a separate access trail to reach the ships ladder. 

Access Ladder 

Installation of a permanent ships ladder down the descent into Devils Hole could by itself have a 

long-term adverse affect on site security, if potential vandals became aware that it is now easier 

to access the cavepool. This could encourage them to attempt to force entry into the site, since 

the stairway into the Hole would now be much safer. However, the improved detection and 

deterrence systems and the limited (enclosed) access should more than balance this risk. 

The ladder and the accompanying handrails would have a major beneficial impact on the safety 

of researchers accessing the Hole. While the current modes of access are not unsafe per se, the 

presence of a fixed ladder will reduce the risk of injury, speed the descent, and make it feasible 

for a single researcher to conduct certain monitoring activities alone. 

Monitoring Platform & Equipment 

The construction of a sectional, lightweight, portable monitoring platform would have no impact 

on the security of the site. It would, however, have a beneficial impact on the safety and 

convenience of monitoring activities. Researchers could store the platform in sections at the 

edge of the pool and would no longer have to transport their makeshift platform down the 

descent, removing a substantial safety risk. The easily-assembled platform would also enable a 

single researcher to conduct monitoring activities when appropriate to the monitoring task. In 

addition, the built-in measuring system would enable more convenient and accurate sampling 

techniques and analysis of scientific variables. 

Removal of the existing still well and frame, and subsequent reliance on pressure transducers for 

water level monitoring, will improve the convenience and safety of ongoing monitoring 

operations for researchers. The monitoring of water level in the pool will be done by connecting 

a new staff gage to the pressure transducers. 

Security System 

The security system—more cameras, more (and more effective) motion sensors, improved 

communications capability, still-image transmission--will provide deterrence, improved 

detection and response capabilities, and aid in criminal prosecution of violators. These are all 

beneficial, long-term impacts on site security. 

The improved system will reduce the incidence of false alarms, thereby making it more 

worthwhile for Rangers to respond to first-alarms. Rangers would also be able to view and 

capture images from the site, thereby making their actions more responsive to the actual 

situation. 
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The enhanced security system would have no direct impact on researcher safety. But to the 

extent that improvements in site security further reduce the danger that the area around the cliff 

would become unstable due to degradation from vandals and further endanger staff access, this 

could produce a beneficial indirect impact. 

Communications Infrastructure 

 

Under Alternative A, the Park would use a dedicated satellite link to provide Internet 

transmission for the webcam images, both to the Visitors Center for interpretive use, and to the 

Ranger station for security monitoring. This is the communications backbone that enables the 

enhanced security system and visitor experience, so its impacts are beneficial, major, and longterm. 

While installing dedicated satellite internet transmission would have no impacts on researcher 

safety, it could have beneficial, minor, and long-term impacts on the actual conduct of 

monitoring activities, if researchers can send, store and receive video transmissions to and from 

colleagues offsite. 

Power Supply 

The additional power required for the upgrades in cameras and monitors would not itself produce 

direct impacts on site security or researcher safety. The solar array would be installed in a place 

and manner which did not interfere with research activities by, for example, shading the Hole 

and thereby limiting the sunlight needed for the pupfish and their habitat to thrive. Its location 

has also been chosen to minimize its visibility to visitors, and therefore reduce its likelihood of 

being a target of malevolence. 

Site revegetation 

Site revegetation activities will not impact site security or researcher safety. Revegetation will 

occur before the new fenceline, which will limit access to the revegetated area, is installed. 

Cumulative Impacts

The potential water projects in the cumulative scenario will not contribute to cumulative impacts 

from Alternative A to site security or researcher safety, and thus Park operations. Being so 

distant from the site, any of those projects, if implemented, would not impinge on the site area 

directly, and so would not compromise or enhance the security infrastructure of the site. Their 

remoteness from the site would also preclude any impact on researcher safety. 

The Refuge planning activities are also not likely to contribute to cumulative impacts of this 

project on Park operations, with one possible exception: if either the transportation projects or 

visitors services projects bring significantly increased traffic to (or past) the site, then this could 

put increased pressure on the security system, simply by increasing the probability of malicious 

attempts. This could further degrade the fragile habitat of the pupfish, and therefore its recovery. 
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Conclusion

Impacts to site security from Alternative A will be beneficial, moderate, and long term, thereby 

having a positive impact on the efficiency and effectiveness of Ranger enforcement. The 

improvements to the fence, the camera system, and the motion detection will provide deterrence 

benefits as well as enhanced detection and enabling increased response efficiency. 

Impacts to the safety of scientific research activities from Alternative A will be beneficial, major, 

and long term, thereby having a positive impact on Park operations. The installation of a 

permanent ships ladder at Devils Hole will make descent into the site more steady, and enable a 

single researcher to conduct monitoring activities while being fully equipped. The creation of 

the segmented portable monitoring platform will also enable a single researcher to conduct 

monitoring, and provide convenience and consistency to the measurements taken by researchers 

over the shelf. 

4.2.2.8 Cultural Resources 

Impacts Analysis 

As discussed in Section 3.8, the two primary tangible resource conditions that sustain the cultural 

use and significance of Devils Hole for the affected tribes are site access and the water level in 

the cavepool itself. In addition, equipment additions into the Hole impact the intangible spiritual 

energy of the site. The impact analysis will focus on cultural resource implications of effects on 

these conditions. 

Fenceline

As described in Section 4.2.2.2, the installation of the fenceline under Alternative A is not 

expected to cause sediment, fuels, or oils to be deposited into Devils Hole because the majority 

of the fenceline is sufficiently remote from the Hole, and potential contaminants are not likely to 

be substantial enough to travel far within a given aquifer. No changes in groundwater level are 

expected to result from the fenceline installation. In addition, BMPs will be utilized throughout 

construction to minimize sediment or potential fuel leaks or spills from migrating throughout the 

construction site. For these reasons, fenceline installation would have negligible adverse impact 

on the contribution that the water level provides to cultural significance. 

Once installed, the new fenceline will encompass a larger land area than the existing fence, and 

in conjunction with the floodgate will allow for an improvement in surface drainage and 

infiltration rates. The improved natural drainage is likely to help maintain groundwater quality, 

nutrient levels and temperature. These are beneficial impacts to the cultural resource value of 

Devils Hole. 

The proposed fenceline in Alternative A adds a dogleg to the south and northwest of the Hole. 

This new fenceline closes off visitor access to a previously accessible area bounded by the new 

fenceline to the south and west and roughly by an imaginary line extending northwest 
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approximately 100’ from the visitors platform up the hillside. Because the Park has not been 

given any specific site use locations by the tribes, the Park cannot determine whether denying 

access to this particular portion of the site will effect the cultural use of the site by affected 

tribes. 

However, the use of double-angled Twinbar fencing along certain portions of the fenceline could 

be perceived by the tribes as causing a major adverse impact on the cultural integrity of the site, 

because it adds to the perceived intensity of human intrusion on the site. Its presence as a more 

visible imposing and defensive structure could detract from, and perhaps overwhelm, the actual 

beneficial effect of protecting the site’s natural resources from further intrusion and degradation. 

The Twinbar fenceline clearly limits access to the site; that is its purpose. The Park believes the 

larger risk to the integrity of Devils Hole habitat values requires such a measure, and would work 

with affected tribes to minimize the visual impact of the enclosed trail to the extent possible. 

Visitors Platform, Access, & Interpretation 

The impacts on water resources of enclosing the visitors platform, removing the fencegate below 

it, and constructing and enclosed access trail are described in Section 4.2.2.2. Throughout this 

process, BMPs would be implemented in order to limit sediment movement and any accidental 

fuel spills from equipment to the maximum extent possible, at both the platform and trail 

construction sites. Once installed, the enclosure of the visitors platform and trail are not likely to 

impact groundwater. As with the fenceline, these facilities are likely to have a beneficial impact 

on groundwater quality in this area. By limiting visitors to areas within the enclosures, these 

facilities will protect both Devils Hole and its surrounding groundwater from detrimental 

impacts. So these activities will ultimately benefit the cultural values of the site. 

However, the creation of the enclosed tunnel trail to the visitors platform could be perceived by 

the tribes as causing a major adverse impact on the cultural integrity of the site, because it adds 

to the perceived intensity of human intrusion on the site. Its presence as a highly visible 

enclosed structure could detract from, and perhaps overwhelm, its actual beneficial effect of 

protecting the site’s natural resources from further intrusion and degradation. As with the 

fenceline overall, the access trail enclosure clearly limits access to the site; that is its purpose. 

The Park believes the larger risk to the integrity of Devils Hole habitat values requires such a 

measure, and would work with affected tribes to minimize the visual impact of the enclosed trail 

to the extent possible. 

The improvements to overall visitor education and interpretation from creating video-based 

display at the Visitors Center will have beneficial impact on the cultural value of the site by 

enhancing awareness of the special and fragile nature of the site without creating such high 

increases in actual visitation traffic that site resources, including current roads, are degraded. As 

mentioned in Section 4.2.2.6, the Park does not expect a major increase in visitation. 
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Access Ladder

As described in Section 4.2.2.1, the risk of groundwater contamination from the installation of 

the ladder is low. Once the ladder is constructed and installed, no impacts to groundwater can be 

expected. The addition of the ladder will aid directly to the protection of natural resources at the 

Devils Hole site, because allowing researchers safe access to the Hole will prevent the need to 

drag temporary ladders in and out of the site, which can lead to erosion. Thus, the cultural value 

associated with sustaining the water resource will be benefited by enhancing the safety of 

monitoring activities. 

Access to culturally important areas of the site will not be affected by constructing a permanent 

ships ladder into the hole. 

Monitoring Platform & Equipment

As described in Section 4.2.2.1, the level of risk of groundwater impacts occurring would be 

slightly greater than under the installation of the ladder due to the very close proximity of the 

installation area to Devils Hole. BMPs will be applied to help mitigate against the potential 

contamination from sediment movement. Once installed, the monitoring platform is not 

expected to impact groundwater quality or movement. Further, safer and permanent access to 

research locations would likely prevent the erosion caused by the movement of temporary 

platforms in and out of the vicinity. Thus, the cultural value associated with sustaining the water 

resource will be benefited by enhancing the safety and convenience of monitoring activities. 

Access to culturally important areas of the site will not be affected by constructing and deploying 

a segmented removable monitoring platform for use in the Hole. 

Security System

As described in Section 4.2.2.2, the minor ground disturbances required to install the security 

systems under Alternative A, including trenching additional cables and mounting cameras, are 

not expected to impact groundwater level, quality, movement or temperature. Cable or camera 

installations would not be expected to be deep enough to reach or impact groundwater. Security 

system operations would also not impact groundwater directly; to the extent that security 

improvements deter breaches of the fenceline, which can lead to disturbance or erosion of 

sediments into the Hole, groundwater features could be enhanced. Thus, the cultural value 

associated with sustaining the water resource will be benefited by enhancing the intrusion 

detection and security capabilities at the site. 

Access to culturally important areas of the site will not be affected by upgrading the security 

components that protect the area. 

Communications Infrastructure

As described in Section 4.2.2.2, no impacts to groundwater quality or movement would be 

expected as a result of the installation or operation of communications infrastructure under 
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Alternative A. Digging and burial will not reach groundwater. Thus, the cultural value 

associated with sustaining the water resource will be benefited by enhancing the protection 

afforded by improved communications infrastructure at the site. 

The installation of a satellite or microwave dish at the site could contribute to the perception of 

increased human disturbance of the site, which could lead to perceptions of adverse impact by 

affected tribes. The Park will attempt to locate the dish to cause minimum visual disruption to 

the appearance of the site. 

Power Supply

Construction equipment and the installation of the 300 square feet of photovoltaic cells are likely 

to result in minor ground disturbances, which are not expected to reach or impact groundwater. 

Cable installation would not be expected to be deep enough to reach or impact groundwater. 

Operations would not impact groundwater quality or movement. Thus, the cultural value 

associated with sustaining the water resource will be benefited by installing sufficient power to 

match the security needs of the site. 

The installation of a solar array and ancillary equipment at the site could contribute to the 

perception of increased human disturbance of the site, which could lead to perceptions of adverse 

impact by affected tribes. The Park will attempt to locate the array to cause minimum visual 

disruption to the appearance of the site, while still optimizing power performance. 

Site revegetation

Site revegetation will take place in the area south of the platform that would be newly fenced off 

from human traffic. As described in Section 4.2.2.2, site revegetation techniques in Alternative 

A are not likely to have more than a negligible though beneficial impact on groundwater within 

the vicinity of Devils Hole. These activities would help restore natural drainage and infiltration 

rates which could benefit groundwater. Thus, the cultural value associated with sustaining the 

water resource will be benefited by revegetation at the site. 

Revegetation will have no impact on access issues at the site. 

Cumulative Impacts 

As described in Section 4.2.2.2, since the implementation of Alternative A would have only 

short-term adverse impacts on groundwater but long-term beneficial impacts to the overall 

hydrology of the region by allowing more natural drainage, no changes to groundwater levels 

within Devils Hole are expected to result from the implementation of Alternative A. Because of 

this, Alternative A is unlikely to contribute to the cumulative water effects described above, and 

therefore, the cultural value associated with sustaining the water resource would not suffer 

cumulative cultural resource impacts. 
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Conclusion 

As described in Section 4.2.2.2, overall impacts to water from the implementation of Alternative 

A can be expected to be partly adverse and minor in the short-term and beneficial and minor in 

the long-term, and covering a medium-sized area around the project site. The cumulative effects 

on groundwater from other past, present, and reasonably foreseeable projects, in conjunction 

with Alternative A, could be expected to be adverse, moderate, long-term, and project area-wide, 

but virtually none of these impacts would be attributable to Alternative A itself. Thus, the 

overall impact of Alternative A on the cultural value of a sustainable water resource would be 

minor, beneficial, and long-term. 

The impact on access to Devils Hole is impossible to analyze specifically without further 

knowledge of affected tribes’ actual use of particular areas of the site. The new fenceline closes 

access to roughly 1/3 of an acre of the site, south and west of the visitors platform. 

Several of the project components could increase the perceptions by the affected tribes of too 

much human interference with the simple power and beauty of the site, which form a part of its 

cultural value. The Park acknowledges that these impacts could be perceived by the tribes to be 

major, but believes its proposed actions are necessary to preserve the other resource values on 

which cultural significance ultimately depends. The Park will work to minimize these impacts to 

the extent feasible. 

The improvements to interpretation are not expected to cause major increases in visitation to the 

site, but they will have minor beneficial impact on the overall cultural values by increasing 

public awareness of the unique and fragile nature of the site and the importance of its 

preservation, which are goals consistent with the tribal concerns. 

The level of impact on cultural resources would not result in impairment of park resources that 

fulfill the specific purposes identified in the enabling legislation or that are essential to the 

natural or cultural integrity of the park. The Timbisha Shoshone have, with some reservations, 

selected Alternative A as their preferred alternative. 
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4.2.3 Alternative B 

4.2.3.1 Soils and Geology 

Impacts Analysis

Fenceline 

Impacts to soils from the installation of fencing under Alternative B can be expected to be 

similar as those impacts discussed above, under Alternative A. The same heavy equipment will 

be used, and the same BMPs would be applied. As with Alternative A, displaced soils will be 

properly disposed of if they contain any potential pollutants, or, if clean, re-introduced during the 

Habitat Restoration activities (see below) after construction is completed. 

Operational impacts to soils from the construction and use of this fenceline will result from the 

fact that the fenceline will encircle the entire self-contained watershed of Devils Hole. This will 

require ~2350 linear feet of chainlink fencing and ~175 linear feet of Twinbar High Security 

fencing, with fence posts placed every 8-9 feet; resulting in approximately 290 fence posts held 

in the soil with poured cement. This would result in permanent soil displacement at each of 

these locations. The chainlink nature of this fence, combined with the large, watershed-sized 

area that would be fenced in would likely allow for most soils and gravel to travel freely through, 

though small buildups may occur. Soil aeration and revegetation techniques applied are likely to 

aid in restoring natural sediment flow and stability around the fenced in area. 

Visitors Platform, Access, & Interpretation 

The installation of the railings surrounding the visitors platform and access trail as described 

under Alternative B is likely to impact soils within the project area. The existing trail to the 

visitors platform will remain and a wooden handrail will be installed on both sides of the trail. 

Construction activities have the potential to cause soil compaction in the areas surrounding the 

platform, but construction disturbance will be limited to using a posthole drill for railings 

supports along the trail. Additionally, the presence of construction workers close to the edge of 

Devils Hole has the potential to dislodge soils and cause them to erode down into the Hole. Any 

displaced soils will be handled as discussed above. 

Access 

Alternative B leaves the existing access scenario—a removable ladder—as is, but increases 

safety and accessibility by adding a permanent handrail down the west side of the cliff. The 

handrail will be anchored to the cliffside at four locations along its descent. At the bottom, the 

handrail continues down the remaining 40’ to the water’s edge. The bottom handrail will be 

secured by posts placed every 8’. The method for securing these posts is described in Section 

2.2.2. Either method requires drilling with industrial power hand tools into rock that is close to 

the cavepool. These anchors are not expected to impact soils, although the drilling could cause 

some rock pieces to be dislodged and then deposited near or into the Hole. As described above, 

attempts will be made to minimize vibration by utilizing the largest rock sizes feasible into 
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which to place bolts, and minimizing the size of drill bit. In addition, rotary hammers can be 

fitted with a large fan and attachable dust collector to minimize deposition of shavings and small 

rock materials. As described above, other construction BMPs would be applied to minimize soil 

contamination, erosion, and disturbance. 

Monitoring Platform & Equipment 

Construction impacts from the installation of the monitoring platform under Alternative B can be 

expected to result from the use of construction machinery, including a crane and scaffolding, as 

well as the presence of workers, near the edge of the Hole. Soil disturbance, in the form of 

compaction and displacement, as well as erosion into the Hole, may result from construction 

activities. In addition, drilling the anchor holes could cause some rock pieces to be dislodged 

and then deposited near or into the Hole. Similar precautions in the selection of rock areas and 

tool accessories as described for Access above would be implemented. 

Security System 

The installation of security cameras under this Alternative is the same as under Alternative A. 

No operational impacts to soils can be expected from the use of the security system. 

Communications Infrastructure 

No impacts to soils are expected from the use of cellular transmission at this site. No additional 

infrastructure will be installed. 

Power Supply 

Impacts to soils from the installation of an 180-square foot solar array under this alternative can 

be expected to be the same as those discussed under Alternative A. 

Site revegetation 

Overall impacts from natural re-seeding are likely to be beneficial. Regular watering will speed 

the process of natural re-seeding after the fence and access trail construction activities. The 

benefits of restoring a native vegetative community in the area are mentioned in Alternative A. 

These benefits might not be realized if the slower process of letting the area establish itself 

naturally were impeded by the intrusion of invasive plants in the area. 

Cumulative Impacts

Currently, none of the water-related or Refuge planning projects can be expected to impact soil 

resources within the vicinity of Devils Hole. Since each of these projects would exist outside of 

the Devils Hole surface watershed, no soils would be impacted and no changes to sediment 

movement would occur. Additionally, these activities would not influence any of the soils that 

supply nutrients to Devils Hole. However, as the Refuge improvement projects are planned in 

more detail, specific measures would be taken to ensure that they do not jeopardize or adversely 
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affect critical habitat for the DH pupfish. This would include considering any project 

components that would alter soil movement in and around Devils Hole. Alternative B would not 

contribute to cumulative impacts from the scenario described above. 

Conclusion

Overall impacts to soils from the implementation of Alternative B can be expected to be partly 

adverse and partly beneficial, minor, both short- and long-term, and cover a medium sized area 

around the project site. Some impacts, such as compaction due to construction and installation 

activities will be short-term, while others, such as the installation of poured concrete for fencing 

posts, will be long-term. Mitigation measures that will be required to offset these impacts 

include the implementation of BMPs to decrease erosion and minimize vibration and rock 

deposition, as well as habitat restoration techniques. Adverse impacts to soils will result from 

the installation of project components (fencing, railings, the solar array, etc.) that permanently 

displace soils. Beneficial impacts can be expected to result from the construction of a trail and 

secure fencing. These components of the project will help to ensure that visitors stay in 

approved areas and avoid going off-trail which can lead to additional soil compaction and 

erosion over time. The cumulative effects on soils from other past, present, and reasonably 

foreseeable projects, in conjunction with Alternative B, would be negligible. 

Because there would be no major adverse impacts to a resource or value whose conservation is 

1) necessary to fulfill specific purposes identified in the establishing legislation or proclamation 

of the park; 2) key to the natural or cultural integrity of the Park or to opportunities for 

enjoyment of the Park; or 3) identified as a goal in the Park’s GMP or other relevant NPS 

planning documents, there would be no impairment of the Park’s resources or values with 

respect to soils. 

4.2.3.2 Water 

Groundwater

Impacts Analysis 

Fenceline

The fenceline in Alternative B is designed to encompass virtually the entire drainage into Devils 

Hole. 

The installation of the fenceline under Alternative B will result in soil compaction, disruption, 

and potential erosion as discussed under Section 4.2.3.1. As with Alternative A, potential 

groundwater impacts from the construction of the fenceline as proposed in Alternative B could 

result from sediment, fuels, and oils eroding or leaking into Devils Hole and traveling through 

area aquifers. If sediment erodes into Devils Hole, it could cloud the surface of the water, 

blocking sunlight and effectively increase the temperature as described above. Additionally, 

fuels and oils could potentially contaminate the water found within Devils Hole. Since the Hole 

is directly connected to groundwater, these impacts could extend to nearby aquifers as the water 
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travels. The risk of this occurring during fenceline installation is minimal due to the majority of 

the fenceline being sufficiently remote from the Hole; and any potential contaminants are not 

likely to be substantial enough to travel far within a given aquifer. No changes in groundwater 

level are expected to result from the fenceline installation. BMPs will be utilized throughout 

construction in order to ensure that limited sediment or potential fuel leaks or spills migrate 

throughout the construction site. If any potential contaminants reach groundwater, they can be 

expected to dissipate, especially once construction activities are finished. The depths to which 

fence posts will be installed are not expected to enough to reach groundwater. 

Once the fenceline is fully installed and operated, it would not be expected to influence 

groundwater quality or movement. It would be sufficiently separated from any groundwater. 

Further, this new fenceline will encompass a larger land area than the existing fence or 

Alternative A, allowing for an improvement in surface drainage which could result in a decrease 

in sediment being washed into Devils Hole that could make its way into area groundwater. This 

will aid in protecting surface water quality, temperature and overall chemistry by restoring 

natural sediment fluctuations and infiltration rates. 

Visitors Platform, Access, & Interpretation

As described above under the impacts of fenceline installation, erosion and runoff caused by 

construction of handrails to the visitors platform and removal of the gate below should not 

impact groundwater quality. However, if significant rock and sediment were deposited into the 

Hole at an above-normal rate, it could increase water temperature in the cave pool as these 

materials absorb solar energy. The risk of this occurring during construction of the handrails 

would be low, due to low intensity of construction and drilling for the handrail supports. If this 

were to occur, some of the impact would likely dissipate after construction activities end as 

sediment particles settle onto substrate. Platform removal under this alternative would have the 

same impacts as in Alternative A. Handrail construction would result in loose sediments but 

they would be unlikely to reach groundwater. Throughout this process, BMPs would be 

implemented in order to limit sediment movement and any accidental fuel spills from equipment 

to the maximum extent possible, at both the platform and trail construction sites. Once installed, 

the handrails to the visitors platform are not likely to impact groundwater. As with the fenceline, 

removal of the fencegate below the platform is likely to have a beneficial impact on groundwater 

quality in this area. By limiting visitors to areas within the enclosures during supervised tours, 

these facilities will protect both Devils Hole and its surrounding groundwater from detrimental 

impacts. 

Once installed, the handrails along the trail are not likely to impact groundwater. As with the 

fenceline, these facilities are likely to have a beneficial impact on groundwater quality in this 

area. By limiting visitors to areas that are sufficiently far enough from Devils Hole, these 

facilities will protect both Devils Hole and its surrounding groundwater from detrimental 

impacts. 
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Access

The impacts to groundwater from the installation of the handrail down the crevasse would come 

from contamination migrating from sediment and equipment fuel into groundwater at the project 

site. Construction equipment and activities and their impacts on soil movement and compaction 

for the stairway are described in Section 4.1. The close proximity of the proposed handrail to the 

surface of Devils Hole increases the risk of eroded sediments reaching the water from that of 

other project components, such as the fenceline, that are further away. Additionally, working 

directly on the steep slopes, chipping rocks and drilling anchors into the cliff would increase the 

risk of sediments and rocks entering Devils Hole. By adhering to BMP requirements, the 

appropriate selection of rock segments to receive anchors, selection of the smallest possible drill 

bits, and the use of dust collectors for rotary hammers, the Park can aid in sediment control and 

further limit this risk. As discussed above, these impacts would most likely dissipate once 

construction is complete. 

Once the handrail is installed, no impacts to groundwater can be expected. The addition of the 

handrail, like other project components, will aid in the protection of natural resources at the 

Devils Hole site. Allowing researchers safe access to the Hole will prevent the need to drag 

temporary ladders in and out of the site, which can lead to erosion. 

Monitoring Platform & Equipment 

As with removal of the fencegate below the visitors platform, any potential impacts to 

groundwater with the installation of monitoring platform would come from the migration of 

sediment and equipment fuels into Devils Hole. The types of impacts to groundwater quality and 

temperature would be the same as described above under the other project components. The 

level of risk and intensity of these impacts would be greater than under the installation of the 

staircase due to the very close proximity of the proposed platform location along the vertical cliff 

face to the east of Devils Hole. The platform as designed under Alternative B will consist of a 

hinged platform bolted into the east wall of the Hole that can be lowered when needed. 

Scaffolding and a small crane will be required during installation so pieces of the platform can be 

lowered down the cliff face. Additional scaffolding would be required to span Devils Hole 

during construction. As discussed in previous analysis sections, construction work this close to 

Devils Hole raises the risks of sediment, rocks loosened during drilling, fuels and oils to get into 

the Hole and travel further into area aquifers. These actions could lead to temporary changes in 

nearby groundwater quality and temperature that would most likely dissipate once construction 

ends. BMPs will be applied to help mitigate against the potential contamination from sediment 

movement. Once installed, the monitoring platform is not expected to impact groundwater 

quality or movement. Further, safer and permanent access to research locations would likely 

prevent the erosion caused by the movement of temporary platforms in and out of the vicinity. 

Security System

The minor ground disturbances required to install the security systems under Alternative B, 

including trenching additional cables and mounting cameras, are not expected to impact 

groundwater quality, movement or temperature. Cable or camera installations would not be 
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expected to be deep enough to reach or impact groundwater. Security system operations would 

also not impact groundwater directly. To the extent that security improvements deter breaches of 

the fenceline, which can lead to disturbance or erosion of sediments into the Hole, groundwater 

features could be enhanced. 

Communications Infrastructure

No impacts to surface water would be expected as a result of the installation or operation of 

communications infrastructure under Alternative B. 

Power Supply

The minor ground disturbances required to install the power supply under Alternative B are not 

expected to impact surface water. Operations would not impact surface water. 

Site revegetation

Site revegetation techniques under Alternative B are not likely have more than a minor, 

beneficial impact on surface within the vicinity of Devils Hole. These activities would help 

restore natural drainage and improve soil retention which can limit the potential for sediment 

runoff into Devils Hole. Steady and natural levels of infiltration via healthy soils would help 

maintain groundwater quality and temperature. Nutrient and dissolved solids levels would most 

likely fluctuate within normal limits within a healthy ecosystem overtime. 

Cumulative Impacts 

There have been major, direct and indirect adverse cumulative impacts to the water level in 

Devils Hole from past groundwater pumping activities. Each of the proposed water-related 

development projects described in the cumulative scenario has the potential to change 

groundwater levels and flow rates within the regional aquifer that includes Devils Hole. As 

discussed in Section 3.2, the underlying hydrogeology of this entire region is heterogeneous and 

mostly unknown. The specific interaction of proposed groundwater use activities and 

groundwater level and quality in Devils Hole is difficult to quantify within the scope of this EA. 

Each of these proposed projects would occur outside of this protected groundwater region; 

however, given the unknown hydrogeologic connections in this region, changes in water level in 

Devils Hole could occur. 

Refuge planning projects as they are currently described in the cumulative scenario are not likely 

to impact groundwater in or around Devils Hole; more detailed information and planning would 

be needed to accurately assess the potential impacts these projects may have. 

Since the implementation of Alternative B would have only short-term adverse impacts on 

groundwater but long-term beneficial impacts to the overall hydrology of the region, no changes 

to groundwater levels within Devils Hole are expected to result from the implementation of 

Alternative B. Because of this, Alternative B is unlikely to contribute to the cumulative effects 

described above. 
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Conclusion 

Overall impacts to groundwater from the implementation of Alternative B can be expected to be 

adverse and beneficial, minor, short-term, and cover a medium sized area around the project site. 

Adverse impacts, such as potential contamination and decreased infiltration due to construction 

and installation activities will be short-term. Mitigation measures that will be required to offset 

these impacts include the implementation of BMPs to decrease erosion, as well as habitat 

restoration techniques. Beneficial impacts can be expected to result from the construction of a 

trail and secure fencing. These components of the project will help to ensure that visitors stay in 

approved areas and avoid going off-trail which can lead to additional soil compaction and 

changes in infiltration over time. The cumulative effects on groundwater from other past, 

present, and reasonably foreseeable projects, in conjunction with Alternative B can be expected 

to be adverse, moderate, long-term, and project area-wide. The level of impact on groundwater 

resources would not result in impairment of park resources that fulfill the specific purposes 

identified in the enabling legislation or that are essential to the natural or cultural integrity of the 

park. 

Surface Water

Impacts Analysis 

Fenceline

Impacts to surface water from the installation of the fenceline under Alternative B can be 

expected to result from the potential erosion of soils and any fuel spills or leaks from 

construction equipment. As discussed in Section 4.1 and above in the groundwater impacts 

analysis, soil compaction, disturbance, the removal of vegetation and the use of heavy machinery 

that requires fuel and oils all have the potential to impact surface water. As discussed throughout 

the analysis sections above, the transport of sediments, fuels and oils into Devils Hole has the 

potential to alter water chemistry, quality and temperature. BMPs will be incorporated into all 

construction activities and should help to mitigate against this risk. Any impacts to surface water 

quality and temperature would most likely be temporary and not last beyond the length of 

construction. Once construction has been completed, this extended fenceline, which will 

encompass the entire natural drainage area, will allow for the natural migration of sediment as 

well as surface drainage to resume in the area surrounding Devils Hole. Extending the fenceline 

out to the natural drainage boundaries will help to ensure that everything that would naturally 

flow toward or into Devils Hole will be able to. This will aid in protecting surface water quality, 

temperature and overall chemistry by restoring natural sediment fluctuations and infiltration 

rates. 

Visitors Platform, Access, & Interpretation

Similar impacts to water quality, chemistry and temperature as described above under the 

fenceline could result from the installation of handrails along the trail and removal of the 

fencegate below. The removal of vegetation, work on steep slopes, soil compaction and 
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disturbance, and the use of machinery require fuel and oils can all lead to the potential for 

contaminated runoff to Devils Hole. Both the removal of the fencegate below the visitors 

platform and the construction of handrails along the access trail will result in soil compaction, 

disturbance and therefore minor changes in surface drainage. However, it is likely that any 

impacts or contamination would only last for the duration of the construction and once the 

platform is installed it would provide a sturdy and safe location for viewing. The 

implementation of BMPs throughout the course of handrail installation and fencegate removal as 

well as habitat restoration efforts once the project is complete will lessen the overall impacts to 

surface water. No components of construction will occur near any surface water bodies aside 

from Devils Hole. 

Access

The installation of the handrails along the slope of Devils Hole would require several anchors on 

the slope to hold the staircase in place. The risks of rock deposition and sediment transport from 

these activities have been described. In the case of Alternative B handrails, there will be anchor 

drilling at several points down the cliff along the ladder, and the multiple anchor points for the 

handrail as it descends further to the water. The risk of rock deposition reaching the water is 

relatively greater than for the ships ladder in Alternative A, though it can be minimized with the 

rock control techniques described multiple times above. Surface water quality, chemistry, and 

temperature could be altered as a result of construction activities such as cement pouring, 

drilling, and lowering handrail components down along the sides of Devils Hole. 

Once in place, the handrail is not expected to impact surface water quality or drainage. The 

addition of this handrail would likely aid in the protection of the water within Devils Hole as it 

would eliminate the need for researchers to carry an access ladder in and out of the Hole which 

has the potential to cause erosion each time. Additionally, these anchors have been designed to 

minimize impact on drainage. 

Monitoring Platform & Equipment 

As with the access stairway, any potential impacts to surface water from the installation of the 

monitoring platform under Alternative B would come from the migration of sediment and 

equipment fuels into Devils Hole, and the dislodging and movement of rock fragments from 

drilling anchor holes. The types of water quality and temperature-related impacts would be the 

same as described above under groundwater. Anchor placement this close to Devils Hole raises 

the risks of sediment, rocks loosened during drilling, fuels and oils to get into the Hole and lead 

to temporary changes in water quality and temperature that would most likely dissipate once 

construction ends. BMPs will be applied to help mitigate against the potential contamination 

from sediment movement. Deposition of rock fragments in the Hole will be minimized by using 

the smallest adequate drill bit, and employing rotary drilling tools that are equipped with dustcatching bags and internal fan. 

Once installed, the monitoring platform is not expected to impact groundwater quality or 

movement. Further, safer and permanent access to research locations would likely prevent the 

erosion caused by the movement of temporary platforms in and out of the vicinity. 
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Security System

As in Alternative A, the construction activities required to install the security system upgrades in 

the upland areas around Devils Hole are not expected to result in more than minor disturbances 

to land and soils in the immediate area. Again, the potential exists for depositing rock and 

dislodging soil that would enter the cavepool below, potentially impacting water temperature and 

quality. These impacts would be minimized by drilling into the largest rock sizes feasible and 

using the minimum size drill bit adequate for the size of the camera mount. 

Communications Infrastructure

No impacts to surface water would be expected as a result of the installation or operation of 

communications infrastructure under Alternative B. 

Power Supply

The minor ground disturbances required to install the power supply under Alternative B are not 

expected to impact surface water. Operations would not impact surface water. 

Site revegetation

Site revegetation techniques under Alternative B are not likely have more than a minor, 

beneficial impact on surface within the vicinity of Devils Hole. These activities would help 

restore natural drainage and improve soil retention which can limit the potential for sediment 

runoff into Devils Hole. Helping to restore natural sediment flow and infiltration rates will 

ensure that Devils Hole is receiving natural levels of sediment and water. This would help 

maintain appropriate nutrient levels and water temperatures that could be expected to fluctuate 

within normal limits for the region. Overall impacts would be beneficial. 

Cumulative Impacts 

There have been major, direct and indirect adverse cumulative impacts to the water level in 

Devils Hole from past groundwater pumping activities. Each of the proposed water-related 

development projects described in the cumulative scenario has the potential to change 

groundwater levels and flow rates within the regional aquifer that includes Devils Hole. Lower 

groundwater levels within the regional karst aquifers could lead to changes in water chemistry. 

These changes may include an increase in the dissolution of calcium carbonate as less water 

travels through the same aquifer conduits. Water temperature in Devils Hole would likely 

increase with a decline in water levels. Sunlight would reach further into the Hole and the 

location of the photic zone would shift as water levels declined over time. General regional 

groundwater withdraw also would have the potential to impact levels of some of the springs 

within the vicinity of AMNWR. Refuge planning projects as they are currently described in the 

cumulative scenario are not likely to impact surface water in or around Devils Hole. Since the 

implementation of Alternative B would have only short-term adverse impacts on surface water 

but long-term beneficial impacts to the overall hydrology of the region, no changes to water 
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levels within Devils Hole are expected to result from its implementation. Because of this, 

Alternative B is unlikely to contribute to the cumulative effects described above. 

In addition, the likelihood of increases in global temperature that have been predicted over the 

next century could increase the water temperature of the pool (IPCC, 2008). Any increase in 

water temperature could adversely impact the pupfish, given the evidence that the pupfish may 

already be existing at the upper edge of the temperature range for sustainable spawning and 

recruitment (Shrode and Gerkin, 1997). 

Conclusion 

Overall impacts to surface water from the implementation of Alternative B can be expected to be 

both adverse and beneficial, minor and moderate, short-term, and cover a medium sized area 

around the project site. Adverse minor impacts, such as potential contamination and runoff due 

to construction and installation activities, will be short-term. Mitigation measures that will be 

required to offset these impacts include the implementation of BMPs to decrease erosion, as well 

as habitat restoration techniques. Beneficial moderate impacts can be expected to result from the 

construction of a visitors trail and a secure fence that encompasses virtually the entire drainage 

into the Hole. These components of the project will help to ensure that visitors stay in approved 

areas and avoid going off-trail which can lead to additional soil compaction and runoff over time. 

Further, this new fenceline will encompass a larger land area than the existing fence, allowing 

for an improvement in surface drainage and infiltration rates. The improved natural drainage is 

likely to help maintain groundwater quality, nutrient levels and temperature. 

The cumulative effects on surface water from other past, present, and reasonably foreseeable 

projects, in conjunction with Alternative B can be expected to be adverse, moderate, long-term, 

and project area-wide. The level of impact on surface water resources would not result in 

impairment of park resources that fulfill the specific purposes identified in the enabling 

legislation or that are essential to the natural or cultural integrity of the park. 

4.2.3.3 Vegetation 

Impacts Analysis

Fenceline 

Construction of the fenceline under Alternative B would necessitate removal of plants located 

along the 2600 linear foot pathway of the fence. Repeated disturbance of vegetation by 

construction vehicles and foot traffic during construction in areas where plants are not cleared 

would also cause damage to plants. Soil compaction as a result of construction activities is likely 

to slightly increase the amount of surface runoff in the immediate area resulting in erosion and 

subsequent damage to plants. Once construction is complete, plants would reestablish along the 

fenceline and in areas disturbed by construction traffic. Native plant reestablishment would be 

enhanced by plantings and soil compaction would be mitigated through habitat restoration 

techniques described below. 
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The fence would exclude herbivore species such as desert bighorn sheep from approximately 

seven acres. Release from browsing by these herbivores would alter plant species composition 

and growth. 

Exotic plants or seeds could be brought to the site with construction equipment. New 

introductions could allow for exotic plants to become established and spread, especially in areas 

where the ground is disturbed by construction activities. Exotic plants currently growing in the 

area can also become established and spread on newly disturbed substrates. However, mitigation 

to ensure that imported material does not contain exotic plant material would be implemented. 

Visitors Platform, Access, & Interpretation 

The existing viewing platform would be retained; however, the fencing and gate beneath the 

platform would be removed. The existing trail to this platform would remain, and a wooden 

handrail would be installed on both sides of the trail and on the platform. Removing fencing and 

the gate could result in trampling and destruction of plants in the immediate vicinity of the 

platform. Installing the handrail would cause minimal site disturbance with few if any plants 

disturbed along the trail. Repeated disturbance of vegetation by foot traffic during these 

activities would also cause damage to plants. Once construction is complete, plants would 

reestablish in areas disturbed by construction traffic. Native plant reestablishment would be 

enhanced by plantings and soil compaction would be mitigated using habitat restoration 

techniques described below. 

Exotic plants or seeds could be brought to the site with construction equipment. New 

introductions could allow for exotic plants to become established and spread, especially in areas 

where the ground is disturbed by construction activities. Exotic plants currently growing in the 

area can also become established and spread on newly disturbed substrates. However, mitigation 

to ensure that imported material does not contain exotic plant material would be implemented. 

Access Stairway 

In this alternative, the existing ladder would remain in place, with the addition of a handrail 

down the side of the cliff. Installing the handrail would not have any impacts on vegetation 

beyond some disturbance of vegetation by foot traffic during installation. Once construction is 

complete, plants would reestablish in areas disturbed by construction traffic. Native plant 

reestablishment would be enhanced by reducing soil compaction using habitat restoration 

techniques described below. 

Monitoring Platform & Equipment 

The monitoring platform would be built off-site and permanently bolted to the east wall of the 

cavern. Installation of the platform would damage plants in the immediate vicinity as a result of 

construction worker foot traffic and temporary scaffolding. Following installation, vegetation on 

the walls of the cavern would be shaded by the platform when in the raised storage position. 
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Security System 

The security system upgrades would require temporary vegetation disturbance in the area of the 

existing tower and for the installation of the buried cable. Installing the cameras in the crevasse 

would not have any impacts on vegetation. Installing a camera on the platform would disturb 

vegetation with the installation of a ground mount and burying cable. Once construction is 

complete, plants would reestablish in areas disturbed by construction traffic. Native plant 

reestablishment would be enhanced by reducing soil compaction using habitat restoration 

techniques described below. 

Communications Infrastructure 

No impacts to vegetation are expected from the use of cellular transmission at this site as no 

additional infrastructure will be installed. 

Power Supply 

Installation of approximately 200 square feet of solar panels, battery charging system, and power 

conditioning equipment would require the permanent removal of plants in the immediate area of 

the panels. Repeated disturbance of vegetation by construction vehicles and foot traffic during 

construction in areas where plants are not cleared would also cause damage to plants. Once 

construction is complete, plants would reestablish in areas disturbed by construction traffic. 

Native plant reestablishment would be enhanced by reducing soil compaction using habitat 

restoration techniques described below. 

Over time, vegetation would need to be pruned or removed as new growth would shade or 

interfere with the solar array. 

Exotic plants or seeds could be brought to the site with fill material. New introductions could 

allow for exotic plants to become established and spread, especially in areas where the ground is 

disturbed by construction activities. Exotic plants currently growing in the area can also become 

established and spread on newly disturbed substrates. However, mitigation to ensure that 

imported material does not contain exotic plant material would be implemented. 

Site revegetation 

Overall impacts from Alternative B revegetation are likely to be beneficial. It is expected that 

local plants would seed themselves, although the natural process of establishing native 

vegetation would compete with the possible establishment of exotic species. 

Cumulative Impacts

Plants in the project area are subject to damage from natural processes, visitation, and periodic 

NPS road and trail maintenance. In addition, upgrades to the transportation infrastructure of Ash 

Meadows NWR are being planned. These plans include the following elements that would 

impact vegetation in the project area: 
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• A new wayside interpretive kiosk on the southern edge of Devils Hole, with a minimal 

primitive parking area. Construction of the wayside would cause impacts through the 

removal of plants in the area of construction introduction of exotic plants. 

• The Desert Refuge complex has undertaken a transportation survey that will provide 

recommendations for improvements to the existing network of roads and parking lots and 

address transportation, management, maintenance, and coordination threats and challenges 

faced by the Refuge (Ash Meadows, 2007). The goal of these improvements is to enhance 

visitor safety and to support the resource protection mission and policies of the NWR. 

Transportation improvements could increase visitation to Devils Hole and result in additional 

impacts to vegetation caused by visitors walking off-trail and introduction of exotic plants. 

There would be long-term, minor, direct adverse cumulative effects on vegetation from past, 

present, and foreseeable future actions. Alternative B would contribute negligible adverse 

cumulative impacts on vegetation. 

Conclusion

Alternative B would result in both adverse and beneficial short and long term, minor, and 

localized impacts on vegetation from construction activities and the installation of new facilities. 

Short-term adverse impacts would primarily result from damage to plants from construction 

traffic and activities. Long-term adverse impacts would primarily occur where plants are 

permanently removed for fencing, camera mount, and solar array. Beneficial impacts would 

result from habitat restoration. 

The level of impact on vegetation would not result in impairment of park resources that fulfill the 

specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 

4.2.3.4 Wildlife 

Impacts Analysis

Fenceline 

Construction activities for installation of 2600 linear feet of fencing and human presence would 

cause temporary displacement and disturbance of resident wildlife for the duration of 

construction. Species are expected to return to the area after construction is completed. Some 

species, such as desert bighorn sheep, may be prevented from using the resources on the project 

site due to habitat alteration and exclusion by the fence. Approximately seven acres would be 

enclosed within the fence. However, the area surrounding the project site supports a large area of 

similar creosotebush scrubland which would provide appropriate habitat for resident wildlife 

species. 
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Visitors Platform, Access, & Interpretation 

Construction activities for removal of the fencing and gate beneath the visitors platform, 

installation of a handrail, and human presence would cause temporary displacement and 

disturbance of resident wildlife for the duration of construction. Species are expected to return to 

the area after construction is completed. Construction activities should not take place between 

April and September to avoid disturbance of nesting owls or breeding bats. 

Access Stairway 

Construction activities for installation of a handrail along the existing access ladder into Devils 

Hole and down the side of the cliff and human presence would cause temporary displacement 

and disturbance of resident wildlife for the duration of construction. Species are expected to 

return to the area after construction is completed. Construction activities should not take place 

between April and September to avoid disturbance of nesting owls or breeding bats. 

Monitoring Platform & Equipment 

The monitoring platform would be built off-site. Initial installation of the monitoring platform 

would cause temporary displacement and disturbance of resident wildlife for the duration of 

construction. Installation should not take place between April and September to avoid 

disturbance of nesting owls or breeding bats. Monitoring activities under this alternative do not 

differ from those in the No Action Alternative, thus no additional impacts to wildlife are 

expected from the repeated use of the monitoring platform at Devils Hole. 

Security System 

Construction activities for installation of security system upgrades and associated human 

presence would cause temporary displacement and disturbance of resident wildlife for the 

duration of construction. Species are expected to return to the area after construction is 

completed. 

Communications Infrastructure 

No impacts to wildlife are expected from the use of cellular transmission at this site as no 

additional infrastructure would be installed. 

Power Supply 

Construction activities for installation of the solar array and equipment and associated human 

presence would cause temporary displacement and disturbance of resident wildlife for the 

duration of construction. Species are expected to return to the area after construction is 

completed. 
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Site Revegetation 

Site revegetation activities would cause temporary displacement and disturbance of resident 

wildlife. Species are expected to return to the area after restoration is completed. 

Cumulative Impacts

Wildlife in the project area is subject to disturbance and damage from natural processes, visitor 

access, monitoring activities, road maintenance, and traffic. There would be continued adverse 

effects on wildlife from vehicles using the roadway, visitation, and monitoring of conditions in 

the cavern. Vehicles passing along the road, visitors to Devils Hole, and monitoring activities 

cause short- term, local disturbance or displacement of wildlife. 

Upgrades to the transportation infrastructure of Ash Meadows NWR are being planned. These 

plans include the following elements that would impact wildlife in the project area: 

• A new wayside interpretive kiosk on the southern edge of Devils Hole, with a minimal 

primitive parking area. Construction of this wayside would cause temporary displacement of 

wildlife during the construction period. 

• The Desert Refuge complex has undertaken a transportation survey that will provide 

recommendations for improvements to the existing network of roads and parking lots and 

address transportation, management, maintenance, and coordination threats and challenges 

faced by the Refuge (Ash Meadows, 2007). The goal of these improvements is to enhance 

visitor safety and to support the resource protection mission and policies of the NWR. 

Transportation improvements could increase visitation to Devils Hole resulting in impacts to 

wildlife. Effects on wildlife would include mortality, restricted movement, introduction of 

exotic plants that could affect wildlife habitat, habitat fragmentation and edge effect, and 

increased human access to wildlife habitats. 

There would be long-term, minor, direct adverse cumulative effects on wildlife from past, 

present, and foreseeable future actions. Alternative B would contribute negligible adverse 

cumulative impacts on wildlife. 

Conclusion

There would be short-term and long-term, negligible, adverse, and localized impacts to wildlife 

as a result of the actions in Alternative B. Short-term impacts are primarily the result of 

temporary displacement during construction activities. Long-term impacts arise from the 

permanent exclusion of wildlife species such as desert bighorn sheep from the fenced area. 

The level of impact on wildlife would not result in impairment of park resources that fulfill the 

specific purposes identified in the enabling legislation or that are essential to the natural or 

cultural integrity of the park. 
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4.2.3.5 Threatened & Endangered Species, Candidate Species, and Species of Special 

Concern 

Impacts Analysis

Fenceline 

Removal of the existing fence and construction of a new fenceline encompassing the entire 

watershed would correct the altered surface runoff and deposition of gravel into the pool caused 

by the existing fence. The new fenceline would allow substrate composition on the shallow 

upper shelf, the principle spawning area for pupfish to receive the natural sediment deposition 

necessary to maintain critical habitat for these species. 

The riffle beetle and Amargosa snail would benefit from correcting surface runoff similar to the 

pupfish. Other special status species occurring in the project area are not expected to be affected 

by construction activities in Alternative B aside from those impacts previously described in the 

wildlife section above. 

Visitors Platform, Access, & Interpretation 

Removal of the fencing and gate beneath the platform and installation of a handrail along the 

trail and on the platform would have no negative impacts on T&E and special status species 

beyond those described in the wildlife section above. The current location along the 

southeastern cliffside would continue to block the same amount of sunlight: about 15 minutes a 

day near the autumnal equinox (September), outside the pupfish spawning season (Weiss, 

2005b). The railings that surround the platform and the access trail would not cause additional 

shadows over the hole. 

Access Stairway 

Construction of an access stairway would cause vibration while drilling into rock for the support 

anchors. Although this vibration would be minimized, there would still be some disturbance due 

to the proximity of pupfish to the cliff face. Construction activities would not take place during 

spawning periods, which typically occur between February and May. There would be no 

additional effect on T&E and special status species beyond those described in the wildlife section 

above. 

Monitoring Platform & Equipment 

Installation of the platform (e.g., drilling holes for wall anchors) would potentially elicit stress 

responses by the pupfish (which would be difficult to quantify). Additionally, given the fragility 

of the fish population, any rock or stone that is released directly into the pool during construction 

could result in direct mortality of pupfish. Construction activities would not take place during 

spawning periods, which typically occur between February and May. 
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This platform would only be lowered and used temporarily during monitoring activities, thus 

would not be expected to have any impacts on primary productivity caused by shading of the 

pool. 

Other special status species occurring in the project area are not expected to be affected by the 

monitoring platform aside from those impacts previously described in the wildlife section above. 

Security System 

The existing security system provides inadequate protection from the possibility that vandals 

could harm critical habitat for the pupfish or that visitors could inadvertently impact the habitat. 

The new system would have beneficial effects by providing greater protection to critical habitat 

and the pupfish population at Devils Hole. Installation of the new security system would have no 

additional impacts on special status species beyond those described in the wildlife section above. 

Communications Infrastructure 

No impacts to T&E species and special status species are expected from the use of cellular 

transmission at this site as no additional infrastructure will be installed. 

Power Supply 

Installation of the new security system would have no additional impacts on T&E and special 

status species beyond those described in the wildlife section above. 

Site revegetation 

No impacts to T&E and special status species are expected from site revegetation activities 

beyond those described in the wildlife section above. 

Cumulative Impacts

Special status species in the project area are subject to disturbance and damage from natural 

processes, visitor access, monitoring activities, road maintenance, traffic, and declining water 

levels in Devils Hole. There would be continued adverse effects on wildlife from vehicles using 

the roadway, visitation, and monitoring of conditions in the cavern. Vehicles passing along the 

road, visitors to Devils Hole, and monitoring activities cause short- term, local disturbance or 

displacement to terrestrial wildlife. 

Declining water levels resulting from groundwater pumping in the late 1960’s and early 1970’s 

dramatically lowered water levels in Devils Hole. Water levels recovered once ground water 

pumping ceased, but since the late 1980’s water levels have again steadily declined. Continued 

Devils Hole pupfish survival is reliant on the structure of its habitat, of which the critical 

characteristic is the availability of shallow water on the upper shelf where pupfish spawn and 

where the bulk of the primary productivity that supports the aquatic community occurs. 
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On September 11, 2004 eighty pupfish, one third of the population, were accidentally killed in an 

incident when traps used to monitor the fish were washed into Devils Hole by a flash flood. 

A number of water related projects that could impact future habitat conditions (i.e., water levels) 

for the Devils Hole pupfish are in the planning process (described in Section 4.1). 

• The Southern Nevada Water Authority (SNWA) has proposed to develop approximately 

8,000 acre-feet of ground water per year from an area north and northwest of Las Vegas. 

There is no definitive timeline when this currently dormant project may be re-activated. 

• The State of Nevada is considering a water rights petition heard in September 2007 involving 

changes in points of diversion for irrigation pumping in the Amargosa Valley. If those 

change applications are granted, Devils Hole water levels could be affected. 

• The Las Vegas metro and the Amargosa Desert are considered desirable areas for further 

development, and many projects are proposed for which the State of Nevada could issue 

water rights. The Park Service has the right to challenge any award of water rights that it can 

demonstrate would threaten the federal reserved water right for Devils Hole. 

• The Desert National Wildlife Refuge Complex is preparing a Comprehensive Conservation 

Plan/Environmental Impact Statement (CCP/EIS) that includes four refuges: Desert, Ash 

Meadows, Pahranagat and Moapa. The CCP/EIS describes the resources, public use, goals, 

objectives, and strategies for Ash Meadows and for the other refuges. It also identifies 

potential environmental effects of potential actions under consideration. The CCP may have 

future beneficial or adverse effects on water levels in Devils Hole depending on management 

decisions made. 

Increased travel on area roads could increase concentrations of airborne particulate matter, 

decreasing solar energy available to fuel primary production in Devils Hole (Wilson and Blinn 

2007). 

In addition, the likelihood of increases in global temperature that have been predicted over the 

next century could increase the water temperature of the pool (IPCC, 2008). Any increase in 

water temperature could adversely impact the pupfish, given the evidence that the pupfish may 

already be existing at the upper edge of the temperature range for sustainable spawning and 

recruitment (Shrode and Gerkin, 1997). 

There would be long-term, major, direct and indirect adverse cumulative impacts on T&E 

species from past, present, and foreseeable future actions. Alternative B would contribute 

moderate beneficial cumulative impacts on T&E species. 

Conclusion

There would be long-term, moderate, direct and indirect beneficial impacts and short-term direct 

negligible or minor adverse impacts to the Devils Hole pupfish as a result of the actions under 

Alternative B. Adverse impacts would result from installation of structures at or near the hole. 

The existing fence has been identified as contributing to habitat alterations that would jeopardize 

the continued existence of these species by adversely modifying the habitat features on which it 

depends. Under this alternative, the fence will be removed and replaced with one that would 
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almost fully restore natural sediment flow and renewal of critical habitat on the upper shelf. 

Additionally, security upgrades would reduce the possibility of habitat damage from vandalism. 

However, the actions under this alternative do not address or negate the long-term adverse 

impacts resulting from declining water levels in Devils Hole. 

The level of impact on special status species would not result in impairment of park resources 

that fulfill the specific purposes identified in the enabling legislation or that are essential to the 

natural or cultural integrity of the park.

4.2.3.6 Visitor Experience 

Impacts Analysis

Fenceline 

Visitor access to the Hole will be limited or prohibited during most, if not all, of the construction 

period. The Park will use a variety of communications tools to notify potential visitors of 

construction. Because the visitors platform will only be accessible during Park-supervised 

tours, it will not be fenced; it will be surrounded by handrails that continue from the access trail. 

The Twinbar fence has a different look than the old cyclone fence it will be replacing; it 

communicates a more forceful security presence, which some visitors may find off-putting. The 

Park will attempt to soften this feature by choosing a color that integrates with the desert 

landscape. On the other hand, the lack of interior fencing around the visitors platform may make 

it an inviting target for vandals. For many visitors the presence of visually daunting Twinbar 

fencing may reinforce the feeling that Devils Hole is a site in need of, and worthy of, strong 

protection. But it is certainly possible that visitors will respond negatively to the more forceful 

presence of the Twinbar. 

Visitors Platform, Access, & Interpretation 

The existing visitors platform will be used for supervised tours of up to 12 visitors at a time, 

which can be arranged from the Visitors Center. Tours would be available for a few hours 

several days a week. Enhanced interpretive panels will also provide greater detail and context on 

the status and ecology of the overall site, and the pupfish itself. In addition, the Park will create 

a display at the Visitors Center with multiple video monitors displaying onsite video. The 

cameras will also feed a web site devoted to Devils Hole interpretation. In addition, the display 

would likely also include a video of a Tribal elder talking about the importance of Devils 

Hole/Ash Meadows. Taken together, these features should benefit the overall visitor experience 

by enabling close-in (remote) viewing of the cavepool itself and reinforcing the cultural 

significance of the site. It is possible, however, that limiting access to supervised tours will 

annoy some visitors, especially those who may have visited the site before. This reaction should 

be addressed by creating material for the interpretive displays that directly addresses the fragility 

of the ecosystem and the pupfish. 

The new access trail to the visitors platform will be convenient and easy to traverse. 
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The Park anticipates a minor increase in onsite visitors, at most, from these changes to 

interpretation. The main benefit will come in the form of increased awareness of those who see 

the exhibits at the Visitors Centers. 

Access 

The new handrails down the slope will have no direct impact on the visitors experience, as they 

should be barely visible, if at all. But to the limited extent that it is visible from outside the fence 

or atop the Visitors Platform, it will further communicate to the visitor the importance of 

monitoring, and the seriousness with which the Park and the Refuge consider the recovery 

mission for the pupfish. 

Monitoring Platform & Equipment 

The monitoring platform will have no direct impact on the visitors experience. It will most 

likely not be visible to visitors, even from the visitors platform. Again, to the limited extent that 

it may be visible from atop the Visitors Platform, it will further communicate to the visitor the 

importance of monitoring, and the seriousness with which the Park and the Refuge consider the 

recovery mission for the pupfish. 

Security System 

The security improvements—increased detection capability, stronger fencing, improved 

communications—will have a negligible impact on the visitor experience, the only possible 

impact being the visibility of the increased camera presence. Again, this serves to reinforce the 

importance of protecting the site. The cameras located in the crevasse serve a security function 

(detecting any disturbance within the crevasse) as well as enhancing the visitor experience by 

allowing remote views from the display in the Visitor Center, or to those with Internet access. 

Communications Infrastructure 

The continuing use of cell phone transmission will have no impact on the visitor experience. 

The cellular transmission tower is already in place, and will not be moved. 

Power Supply 

Enhancing the solar array to meet the increased power requirements of the new security system 

and cameras will have a no impact on the visitor experience. The array will be located in an 

appropriate location to avoid interfering with visitors enjoyment of the site. 

Site revegetation 

Site revegetation will improve the health of the ecosystem and the visual appeal of the site. A 

healthier ecosystem will ultimately enhance the visitor experience, by improving the 

sustainability of the pupfish habitat and aiding its recovery. 
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Cumulative Impacts

Any action taken by governments or private actors that threatens the habitat or survival of the 

pupfish could have a corresponding cumulative impact on the visitor experience. It is technically 

true, however, that because actually seeing the fish itself from the platform is such a rare part of 

the overall Devils Hole experience, any actions that harmed but did not eliminate the fish would 

by themselves not change the experience. In the extreme, only actions that resulted in the 

extinction of the species would impact the visitor experience, by removing the justification for 

the interpretive and security infrastructure in the first place. The Devils Hole pupfish lives a 

precarious existence as a species, and the Park believes it can successfully enforce its federal 

water rights against actions that would endanger it by lowering the water level in the Hole below 

the mandated level. But if such projects went ahead and ultimately led to loss of the fish 

population, the Park could well decide that the site need no longer be maintained and there 

would likely be no visitor experience. 

Some of the projects being planned by the Refuge could impact Devils Hole. The interpretive 

kiosk tentatively planned for south of the Hole would enhance visitor education, providing 

positive benefit. If any transportation projects served to significantly increase traffic along 

Devils Hole Road, that could increase visitors to a point where additional parking facilities might 

be needed. The visitor survey planned by USFWS could be used to make improvements 

elsewhere on the Refuge--at the Visitor Center, for example-- that could ultimately benefit the 

visitors to Devils Hole. Other specific projects are insufficiently mature to analyze potential 

impacts, but given the mission to protect natural resources within the Refuge, it is unlikely that 

any projects that could cause cumulative impacts to the pupfish would move forward without 

sufficient mitigation. 

Conclusion

Overall impacts to the visitor experience from the implementation of Alternative B can be 

expected to be beneficial, moderate, and long-term. While some visitors might experience the 

new, stronger Twinbar fence as visually incongruent with the openness of the landscape (a minor 

adverse impact) and be disappointed that access is limited to supervised tours, the actual 

experience of the site itself will be enhanced by the conduct of the tours, as well as by improved 

interpretive material and improved trail access. The offsite interpretive exhibits at the Refuge 

Visitors Center, the Death Valley National Park’s Furnace Creek Visitor Center, and the 

interpretive web site, both featuring full-motion video from inside the crevasse, will further 

enhance the overall visitor experience. The additional security provided by the security 

infrastructure will improve the sustainability of the visitor experience over time. 
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4.2.3.7 Park Operations 

Impacts Analysis

Fenceline 

The replacement of the compromised cyclone fence with the combination of heavier gauge chain 

link fence around most of the perimeter and Twinbar fencing around gated access area will have 

a beneficial short- and long-term impact on site security. Twinbar fencing is more difficult to 

cut, and its angled top will make it more difficult to scale. An all-Twinbar fence would provide 

more security protection than the combination of chain link with Twinbar, but every possible 

security solution is a tradeoff between cost—in this case, of circling the entire watershed in 

Twinbar fencing--and the value of the enhanced natural drainage enabled by the wider fenceline. 

The Park feels the improved fence could still play an important role in the overall strategy of 

deterring malicious entry into the site. 

The fence would have no direct impact on the safety of staff in conducting monitoring operations 

at the site. To the extent that improvements in site security further reduce the danger that the 

area around the cliff would become unstable and further endanger staff access, this could 

produce a beneficial indirect impact. 

Visitors Platform, Access, & Interpretation 

Alternative B retains the existing visitors platform but limits access to supervised tours. This 

alternative also combines improved off-site interpretation at the Refuge Visitors Center and the 

Death Valley National Park’s Furnace Creek Visitor Center (using webcam video) to enhance 

the overall visitor experience. To the extent that this denial of unsupervised access is perceived 

negatively by visitors (as “taking something away”), it could spark some negative response; the 

extreme manifestation of this could be a higher risk of vandalism at the site overall by visitors 

seeking retaliation or “lashing out.” This would not be likely to result in significantly more 

incidents, but it could put a minor amount of added pressure on the security system. 

The visitors platform and interpretive changes would have no impact on researcher safety. 

Access 

Installation of handrails down the descent into Devils Hole should not have any affect on site 

security. Access to the hole is not so much easier as to tempt vandals significantly, as might be 

the case for the ships ladder in Alternative A. 

The handrails along the descent and at the bottom would have a major beneficial impact on the 

safety of researchers accessing the Hole. While the current modes of access are not unsafe per 

se, the presence of a handrails along the ladder path will reduce the risk of injury, speed the 

descent, and make it feasible for a single researcher to conduct certain monitoring activities 

alone. The handrail at the base will also reduce the risk of injury. 
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Monitoring Platform & Equipment 

The installation of a permanent monitoring platform would have no impact on the security of the 

site. It would, however, have a beneficial impact on the safety and convenience of monitoring 

activities. Researchers would no longer have to transport their makeshift platform down the 

descent, removing a substantial safety risk. The fixed platform would also enable a single 

researcher to conduct monitoring activities by singly operating the fold-down platform 

mechanism. Introducing a mechanical device such as this platform into the situation, as with any 

engineered device, does introduce the possibility of mechanical malfunction or failure, which 

could leave researchers with no platform on any given day. In such a situation, researchers could 

re-deploy the current platform as a back-up. 

Moving the existing still well to the back of the Devils Hole cave will increase the safety and 

convenience of monitoring activities for researchers, who will no longer be physically obstructed 

by its presence at its existing location. The monitoring functions of the well will be retained. 

Security System 

The security system in Alternative B features full-motion video cameras, video recording and 

transmission capability, improved motion sensors, and wider communications bandwidth. These 

features will combine to provide improved deterrence, detection and response capabilities, and 

aid in criminal prosecution of violators. These are all beneficial, long-term impacts on site 

security. 

The system will include compositing software that enables video images from multiple cameras 

to be displayed on a single monitoring screen. This would provide fully functional remote 

monitoring capabilities, thereby enhancing the speed and appropriateness of first response. Also, 

because the improved system will reduce the incidence of false alarms, it will be more 

worthwhile for Rangers to respond to first-alarms. Rangers would also be able to view and 

record video from the site, thereby making their actions more responsive to the actual situation, 

and providing evidence in the case of criminal prosecution. 

The enhanced security system would have no direct impact on researcher safety. But to the 

extent that improvements in site security further reduce the danger that the area around the cliff 

would become unstable due to degradation from vandals and further endanger staff access, this 

could produce a beneficial indirect impact. 

Communications Infrastructure 

The cell phone infrastructure would not be substantially upgraded or changed in Alternative B, 

although its capability to transmit still images would be utilized, thus providing some security 

benefits by enabling Rangers to see alternating site images. 

Utilizing the same cellular infrastructure as now would have no impact on researcher safety. 
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Power Supply 

The additional power required for the upgrades in cameras and monitors would not itself produce 

direct impacts on site security or researcher safety. The solar array would be installed in a place 

and manner which did not interfere with research activities by, for example, shading the Hole 

and thereby limiting the sunlight needed for the pupfish and their habitat to thrive. 

Site revegetation 

Site revegetation activities will not impact site security or researcher safety. 

Cumulative Impacts

The potential water projects in the cumulative scenario will not contribute to cumulative impacts 

from Alternative B to site security or researcher safety, and thus Park operations. Being so 

distant from the site, any of those projects, if implemented, would not impinge on the site area 

directly, and so would not compromise or enhance the security infrastructure of the site. Their 

remoteness from the site would also preclude any impact on researcher safety. 

The Refuge planning activities are also not likely to contribute to cumulative impacts of this 

project on Park operations, with one possible exception: if either the transportation projects or 

visitors services projects bring significantly increased traffic to (or past) the site, then this could 

put increased pressure on the security system, simply by increasing the probability of malicious 

attempts. 

Conclusion

Impacts to site security from Alternative B will be beneficial, major, and long term, thereby 

having a positive impact on the efficiency and effectiveness of Ranger enforcement. The 

improvements to the fence, the camera system, transmission of video, and the motion detection 

will provide deterrence benefits as well as enhanced detection and increased response efficiency. 

The visitors experience will be improved by the addition of supervised tours and the use of 

offsite video displays at the Visitors Centers, although the elimination of unsupervised access to 

the visitors platform could be viewed negatively by Park and Refuge visitors. 

Impacts to the safety of scientific research activities from Alternative B will be beneficial, major, 

and long term, thereby having a positive impact on Park operations. The installation of handrails 

will make descent into the site more steady, and enable a single researcher to conduct monitoring 

activities while being fully equipped. The installation of the mechanical fold-down monitoring 

platform will also enable a single researcher to conduct monitoring, and provide convenience and 

consistency to the placement of the monitoring platform over the shelf. 
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4.2.3.8 Cultural Resources 

Impacts Analysis 

As discussed in Section 3.8, the two primary tangible resource conditions that sustain the cultural 

use and significance of Devils Hole for the affected tribes are site access and the water level in 

the cavepool itself. In addition, equipment additions into the Hole impact the intangible spiritual 

energy of the site. The impact analysis will focus on cultural resource implications of effects on 

these conditions. 

Fenceline

As described in Section 4.2.3.2, the installation of the fenceline under Alternative B is not 

expected to cause sediment, fuels, or oils to be deposited into Devils Hole because the majority 

of the fenceline is sufficiently remote from the Hole, and potential contaminants are not likely to 

be substantial enough to travel far within a given aquifer. No changes in groundwater level are 

expected to result from the fenceline installation. In addition, BMPs will be utilized throughout 

construction to minimize sediment or potential fuel leaks or spills from migrating throughout the 

construction site. For these reasons, fenceline installation would have negligible adverse impact 

on the contribution that the water level provides to cultural significance. 

Once installed, the new fenceline will encompass a larger land area than the existing fence and 

will allow for an improvement in surface drainage and infiltration rates. The improved natural 

drainage is likely to help maintain groundwater quality, nutrient levels and temperature. These 

are beneficial impacts to the cultural resource value of Devils Hole. 

The new fenceline closes off visitor access to a previously accessible area south and west of the 

platform. Because the Park has not been given any specific site use locations by the tribes, the 

Park is not aware of whether denying access to this particular portion of the site will affect the 

cultural use of the site by affected tribes. However, the Timbisha Shoshone have indicated that 

they would prefer to decrease public visitation at Devils Hole, which could be accomplished by 

limiting visitor access to the site. 

Similarly to Alternative A, the use of double-angled Twinbar fencing along certain portions of 

the fenceline could be perceived by the tribes as causing a major adverse impact on the cultural 

integrity of the site, because it adds to the perceived intensity of human intrusion on the site. Its 

presence as a more visible imposing and defensive structure could detract from, and perhaps 

overwhelm, the actual beneficial effect of protecting the site’s natural resources from further 

intrusion and degradation. The Twinbar fenceline clearly limits access to the site; that is its 

purpose. The Park believes the larger risk to the integrity of Devils Hole habitat values requires 

such a measure, and would work with affected tribes to minimize the visual impact of the 

enclosed trail to the extent possible 
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Visitors Platform, Access Trail & Interpretation

Alternative B involves allowing visitor access inside the fenceline and to the platform only 

during supervised tours, and constructing a simple railing along the north side of the trail from 

the entrance gate to the visitors platform. 

The impacts on water resources of removing the fencegate below the visitors platform and 

constructing the railed access trail in the Hole are described in Section 4.2.3.2. Throughout this 

process, BMPs would be implemented in order to limit sediment movement and any accidental 

fuel spills from equipment to the maximum extent possible, at both the platform and trail 

construction sites. Once installed, trail is not likely to impact groundwater. By limiting 

unsupervised access to the interior areas of the site, these facilities will protect both Devils Hole 

and its surrounding groundwater from detrimental impacts. So these activities will ultimately 

benefit the cultural value of the site by benefiting the sustainability of the water resource. 

Limiting visitor traffic to supervised tours would have both beneficial and adverse impacts on the 

access condition of the site. Such limited access enhances the perception of the unique and 

fragile nature of the site and could lead to more respect for the Park’s protection mandate, which 

supports the tribal goal of protection and minimizing disturbance. However, if the access 

limitations preclude or restrict the tribes’ own access to its ceremonial sites, this would be 

perceived as a major adverse impact for the affected tribes. Without knowledge of the specific 

locations used by the tribes for ceremonial purposes, the Park cannot know whether this will 

occur. 

The improvements to overall visitor education and interpretation from creating video-based 

display at the Visitors Centers will have minor beneficial impact on the cultural value of the site, 

assuming they can successfully enhance awareness of the special and fragile nature of the site 

without creating such high increases in actual visitation traffic that site resources, including 

current roads, are degraded. As mentioned in Section 4.2.3.6, the Park does not expect a major 

increase in onsite visitation. 

Access Ladder

As described in Section 4.2.3.2, the risk of groundwater contamination from the installation of a 

permanent handrail down the cliffside is low. Once the handrail is constructed and installed, no 

impacts to groundwater can be expected. Thus, the cultural value associated with sustaining the 

water resource will not be adversely impacted by enhancing the safety of monitoring activities. 

Access to culturally important areas of the site will not be affected by constructing a permanent 

handrail down into the hole. 

Monitoring Platform & Equipment

As described in Section 4.2.3.2, construction work along the vertical cliff along the eastern wall 

of Devils Hole raises the risks of sediment, rocks loosened during drilling, fuels, and oils to get 

into the Hole and travel further into area aquifers. These actions could lead to temporary 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Environmental Consequences 137 

changes in nearby groundwater quality and temperature that would most likely dissipate once 

construction ends. BMPs will be applied to help mitigate against the potential contamination 

from sediment movement. Once installed, the monitoring platform is not expected to impact 

groundwater quality or movement. Further, safer and permanent access to research locations 

would likely prevent the erosion caused by the movement of temporary platforms in and out of 

the vicinity. Thus, while the risks of adverse impacts to the water are greater than in Alternative 

A, the cultural value associated with sustaining the water resource will ultimately be benefited by 

enhancing the safety and convenience of monitoring activities. 

Access to culturally important areas of the site will not be affected by constructing and deploying 

a segmented removable monitoring platform for use in the Hole. 

Security System

As described in Section 4.2.3.2, the minor ground disturbances required to install the security 

systems under Alternative B, including trenching additional cables and mounting cameras, are 

not expected to impact groundwater level, quality, movement or temperature. Cable or camera 

installations would not be expected to be deep enough to reach or impact groundwater. Security 

system operations would also not impact groundwater directly; to the extent that security 

improvements deter breaches of the fenceline, which can lead to disturbance or erosion of 

sediments into the Hole, groundwater features could be enhanced. Thus, the cultural value 

associated with sustaining the water resource will be benefited by enhancing the intrusion 

detection and security capabilities at the site. 

Access to culturally important areas of the site will not be affected by upgrading the security 

components that protect the area. 

Communications Infrastructure

No additional communications hardware or software will be installed under Alternative B. Thus, 

the cultural value associated with sustaining the water resource would not be impacted by 

continuing to use cellular communications infrastructure at the site. 

Power Supply

Construction equipment and the installation of the roughly 200 square feet of photovoltaic cells 

are likely to result in minor ground disturbances, which are not expected to reach or impact 

groundwater. Cable installation would not be expected to be deep enough to reach or impact 

groundwater. Operations would not impact groundwater quality or movement. Thus, the 

cultural value associated with sustaining the water resource will be benefited by installing 

sufficient power to match the security needs of the site. 

The installation of a solar array and ancillary equipment at the site could contribute to the 

perception of increased human disturbance of the site, which could lead to perceptions of adverse 

impact by affected tribes. The Park will attempt to locate the array to cause minimum visual 

disruption to the appearance of the site, while still optimizing power performance. 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Environmental Consequences 138 

Site revegetation

Site revegetation will take place in the area south of the platform that would be newly fenced off 

from human traffic. As described in Section 4.2.3.2, site revegetation techniques in Alternative 

B are not likely to have more than a negligible though beneficial impact on groundwater within 

the vicinity of Devils Hole. These activities would help restore natural drainage and infiltration 

rates which could benefit groundwater. Thus, the cultural value associated with sustaining the 

water resource will be benefited by revegetation at the site. 

Revegetation will have no impact on access issues at the site. 

Cumulative Impacts 

As described in Section 4.2.3.2, since the implementation of Alternative B would have only 

short-term adverse impacts on groundwater but long-term beneficial impacts to the overall 

hydrology of the region by allowing more natural drainage, no changes to groundwater levels 

within Devils Hole are expected to result from the implementation of Alternative B. Because of 

this, Alternative B is unlikely to contribute to the cumulative water effects described above, and 

therefore, the cultural value associated with sustaining the water resource would not suffer 

cumulative cultural resource impacts. 

Conclusion 

As described in Section 4.2.3.2, overall impacts to water from the implementation of Alternative 

B can be expected to be partly adverse and minor in the short-term and beneficial and minor in 

the long-term, and covering a medium-sized area around the project site. The watershed 

fenceline will encompass a larger land area than the existing fence, allowing for an improvement 

in surface drainage and infiltration rates. The improved natural drainage is likely to help 

maintain groundwater quality, nutrient levels and temperature. 

The cumulative effects on groundwater from other past, present, and reasonably foreseeable 

projects, in conjunction with Alternative B, could be expected to be adverse, moderate, longterm, and project area-wide, but virtually none of these impacts would be attributable to 

Alternative B itself. Thus, the overall impact of Alternative B on the cultural value of a 

sustainable water resource would be minor, beneficial, and long-term. 

The improvements to interpretation are not expected to cause major increases in visitation to the 

site, but they will have minor beneficial impact on the overall cultural values by increasing 

public awareness of the unique and fragile nature of the site and the importance of its 

preservation. 

The impact on access to Devils Hole is impossible to analyze specifically without further 

knowledge of affected tribes’ actual use of particular areas of the site. The new fenceline closes 

relatively easy access to roughly 1/3 of an acre of the site, south and west of the visitors 

platform. 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Environmental Consequences 139 

Several of the project components could increase the perceptions by the affected tribes of too 

much human interference with the simple power and beauty of the site, an intangible but real 

resource condition which form a part of its cultural value. The Park acknowledges that these 

impacts could be perceived by the tribes to be major, but believes its proposed actions are 

necessary to preserve the other resource values on which cultural significance ultimately 

depends. The Park will work to minimize these impacts to the extent feasible. 

The level of impact on cultural resources would not result in impairment of park resources that 

fulfill the specific purposes identified in the enabling legislation or that are essential to the 

natural or cultural integrity of the park. The Timbisha Shoshone have indicated that they prefer 

Alternative A over Alternative B. 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Consultation and Coordination 140 

5.0 CONSULTATION AND COORDINATION 

5.1 PUBLIC INVOLVEMENT 

The purpose of the scoping process, as outlined in CEQ’s regulations for implementing NEPA 

(40 CFR 1501.7), is to determine the scope of issues to be addressed in the EA and to identify 

significant issues relating to the Proposed Action. The lead agency is required to invite input 

from Federal, State, and local agencies, affected Native American tribes, project proponents, and 

other interested parties (Section 1501.7 (a)(1)). To satisfy scoping requirements for this project, 

scoping letters were mailed out requesting public and agency input on issues to be addressed in 

the EA. 

The public scoping period for the project began on November 26, 2007 and ended on December 

26, 2007. Several comments were received from the public during this period. The NPS has 

undertaken consultations with State and Federal agencies. These consultation letters are 

presented in Appendices C & D. 

5.2 CONSULTATION

Section 7 of the Endangered Species Act requires that federal agencies, in consultation with the 

U. S. Fish & Wildlife Service, insure that its actions do not “jeopardize the continued existence 

of a listed species or result in the destruction or adverse modification of designated critical 

habitat”. In a letter dated April 16, 2009 (Appendix B), the NPS consulted with the U.S. Fish and 

Wildlife Service, and sought concurrence that the Proposed Action would not adversely affect 

listed or candidate species or proposed or designated critical habitat. In a letter dated May 18, 

2009, USFWS provided its concurrence that “the proposed project is not likely to adversely 

affect the Devils Hole pupfish” (Appendix B). The project area lies within designated critical 

habitat of the Devils Hole pupfish, however, the primary purpose of the project is to improve 

protection of the pupfish and its habitat. Two candidate species, Devils Hole riffle beetle 

(Stenelmis calida) and Armagosa tyronia snail (Tryonia variegata) (U.S. Fish and Wildlife 

Service 1990) also occur in the project area. Protection for these species is likely to be improved 

as a result of this project as well. 

The Nevada Legislature, Nevada Administrative Code Chapter 503 (Nevada Legislature 2008) 

was reviewed for a list of Nevada state protected species that may occur within the project area. 

The Nevada Department of Wildlife administers state protected species programs. One statelisted species, Townsend’s big-eared bat (Corynorhinus townsendii) was identified as potentially 

occurring within the project area. 

The National Historic Preservation Act of 1966 (NHPA) states that "the historical and cultural 

foundations of the Nation should be preserved as a living part of our community life and 

development in order to give a sense of orientation to the American people." The Act requires 

federal agencies to establish programs for evaluating and nominating properties to the National 

Register of Historic Places and to consider the effects of their undertakings on listed or eligible 

properties. Section 106 of the NHPA mandates that federal agencies take into account the effects 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Consultation and Coordination 141 

of their actions on properties listed or eligible for listing in the National Register and give the 

Advisory Council on Historic Preservation a reasonable opportunity to comment. While it does 

not require the preservation of such properties, it does require that their historic or prehistoric 

values be considered in weighing the benefits and costs of federal undertakings to determine 

what is in the public interest. This evaluation takes place through a process of consultation with 

affected tribes and the State Historic Preservation Officer (“Section 106 consultation”). 

Pursuant to federal regulations detailed in 36 CFR 800.8, the Park is planning to coordinate its 

compliance with NEPA (through this Environmental Assessment) with its Section 106 

consultations with the Timbisha Shoshone and Pahrump Paiute tribes. This coordination has or 

will involve the following steps (36 CFR 800.8) by the Park: 

1) Establishing that the proposed action is an undertaking that has the potential to cause 

effects on NRHP-eligible properties 

2) Establishing the parties to be consulted and their roles, possibly including tribes, 

Tribal Historic Preservation Officers, and State Historic Preservation Officers 

3) Ensuring that the preparation of the EA includes appropriate scoping, identification of 

historic properties, assessment of effects, and consultation leading to resolution of 

any adverse effects 

4) Submitting the EA to the interested consulting parties prior to or when making the 

document available for public comment 

5) Provide procedures for resolving objections by consulting parties to the proposed 

action, including avoidance, minimization, or mitigation of adverse effects, if any are 

identified 

As such, the environmental findings described in this EA will be used in Section 106 

consultations to document the types and severity of impacts to the Traditional cultural property 

values of Devils Hole. 

Appendix B contains the correspondence documenting the consultation with appropriate 

interested parties. 

5.3 PREPARERS AND CONTRIBUTORS 

U.S. Department of the Interior, National Park Service, Death Valley National Park 

Mike Bower, Fish Biologist 

Terry Fisk, Hydrologist 

Vicki Wolfe, Park Ranger-Interpretation 

Ed Forner, Assistant Chief, Resource and Visitor Protection Division 

Ed Derobertis, Law Enforcement Ranger 

Michele Slaton, Botanist 

Linda Manning, Wildlife Biologist 

Linda Greene, Chief, Resources Management Division 

Daren Fairbanks, Information Technology Specialist 

Gerry Wolfe, Safety Officer 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Consultation and Coordination 142 

David Ek, Assistant Chief, Resources Management Division 

John Elks, Buildings and Utilities Supervisor 

Leah Bonstead, Archeologist 

U.S. Fish & Wildlife Service 

Christina Nalen, Visitor Services 

Sharon McElvey, Refuge Manager 

El Dorado Engineering 

Ralph Hayes, President 

Nate Glick, P.E. 

Morgan Frampton, P.E. 

Mangi Environmental Group, Inc. 

Jim Mangi, President 

Bruce Kaplan, Senior Environmental Professional, Project Manager 

Kezia Procita, Environmental Analyst 

Karla Hillstrom, GIS Specialist 

Mark Blevins, GIS Specialist 

Ian Martin, Wildlife Biologist 

Priscilla Randall, Registered Landscape Architect 

5.4 DISTRIBUTION LIST FOR ENVIRONMENTAL ASSESSMENT

Cooperators and Interested Parties 

Last Name First 

Name 

Title Office Agency/ 

Affiliation 

Email Address 

All Employees Death Valley National 

Park 

National Park 

Service 

DEVA All Employees 

Arnold Richard Tribal Chair Pahrump Piaute 

Tribe 

rwarnold@hotmail.com 

Back Jennifer Water Rights Branch National Park 

Service 

Jennifer_Back@nps.go

v 

Bair Janet Assistant 

Field 

Supervisor 

Southern Nevada 

Fish and Wildlife 

Office 

U.S. Fish and 

Wildlife Service 

Janet_Bair@fws.gov 

Baldino Cristi Wildlife 

Biologist 

Ash Meadows 

National Wildlife 

Refuge 

U.S. Fish and 

Wildlife Service 

Cristi_Baldino@fws.gov 

Barrett Paul Recovery 

Coordinator 

 U.S. Fish and 

Wildlife Service 

Paul_Barrett@fws.gov 

Blacker David Executive 

Director 

 Death Valley 

Natural History 

Association 

deathvalleynha@earthli

nk.net 

Deacon James Professor 

Emeritus 

 University of 

Nevada, Las Vegas 

deaconj@unlv.nevada.e

du 

Durham Barbara THPO Timbisha 

Shoshone Tribe 

dvdurbarbara@netscap

e.com 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Consultation and Coordination 143 

Last Name First 

Name 

Title Office Agency/ 

Affiliation 

Email Address 

Fuhrmann Kelly Kelly_Fuhrmann@nps.g

ov 

Haskins Rich Deputy 

Director 

 Nevada 

Department of 

Wildlife 

rhaskins@ndow.org 

Hillyard Stanley Professor University of 

Nevada, Las Vegas 

hillyard@unlv.edu 

Lamfrom David Field 

Representati

ve 

 National Parks 

Conservation 

Association 

dlamfrom@npca.org 

McKelvey Sharon Refuge 

Manager 

Ash Meadows 

National Wildlife 

Refuge 

U.S. Fish and 

Wildlife Service 

Sharon_McKelvey@fws

.gov 

Parker Michael Assistant 

Professor 

 Southern Oregon 

University 

parker@sou.edu 

Pister Phil Executive 

Secretary 

 Desert Fishes 

Council 

secretary@desertfishes.

org 

Scoppettone Gary U.S. Geological 

Survey 

Gary_Scoppettone@us

gs.gov 

Sjoberg Jon Supervising 

Biologist 

 Nevada 

Department of 

Wildlife 

sjoberg@ndow.org 

Tripp-Massie Tami Executive 

Director 

 Amargosa 

Conservancy 

info@amargosaconserv

ancy.org 

Williams Bob Field 

Supervisor 

Nevada Fish and 

Wildlife Office 

U.S. Fish and 

Wildlife Service 

Bob_Williams@fws.gov 

Wullschleger John Fisheries 

Program 

Leader 

 National Park 

Service 

John_Wullschleger@np

s.gov 

Media Notifications 

Organization Email Address 

Pahrump Valley Times msmith@pvtimes.com 

Pahrump Valley Times dmcmurdo@pvtimes.com, 

Las Vegas television newsdesk@klastv.com, 

Las Vegas television ktnvnewsdesk@ktnv.com, 

Las Vegas television 5newsdesk@kvvu.com, 

Las Vegas television news3@kvbc.com, 

Channel 41 Pahrump NV mikewood41@yahoo.co.uk, 

Fox TV - LA figueroa@fox11la.com, 

Las Vegas Review Journal rogers@reviewjournal.com, 

Las Vegas Review Journal hbrean@reviewjournal.com, 

Las Vegas Review Journal poconnell@reviewjournal.com, 

Las Vegas Review Journal APlanas@reviewjournal.com, 

Las Vegas Review Journal fcurreri@reviewjournal.com, 

Las Vegas Review Journal fgeary@reviewjournal.com, 

Las Vegas Review Journal bhaynes@reviewjournal.com, 

Las Vegas Sun jean@lasvegassun.com, 

Las Vegas Sun manning@lasvegassun.com, 

Las Vegas Sun slovic@lasvegassun.com, 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Consultation and Coordination 144 

Organization Email Address 

Las Vegas Sun haney@lasvegassun.com, 

Las Vegas Sun metroeditors@lasvegassun.com, 

Las Vegas newspaper corr@thespectrum.com, 

LA Times julie.cart@latimes.com, 

LA Times elizabeth.shogren@latimes.com, 

LA Times chris.reynolds@latimes.com, 

LA Times louis.sahagun@latimes.com, 

LA Times bettina.boxall@latimes.com, 

Las Vegas radio lasvegas_news@metronetworks.com, 

Nevada Magazine jhollister@nevadamagazine.com, 

Nevada Magazine editor@nevadamagazine.com, 

Nevada Magazine ann@nevadamagazine.com, 

Inyo Register/Pahrump Valley Times report. rkflinchum@earthlink.net, 

Death Valley Chamber of Commerce deathvalleych@earthlink.net, 

Owen’s Valley newspaper twoods@sierrawave.net, 

Library Distribution 

Pahrump Community Library 

701 East St. 

Pahrump, Nevada 89048 

 

Amargosa Valley Library 

829 E. Farm Road 

HCR 69 Box 401-T 

Amargosa Valley, Nevada 89020 

 

Bishop Branch Library 

210 Academy Avenue 

Bishop, California 93514 

 

Lone Pine Branch Library 

Washington & Bush Streets 

Lone Pine, California 93545 

 

Ridgecrest Branch Library 

131 East Las Flores Avenue 

Ridgecrest, California 93555 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

References 145 

6.0 REFERENCES 

(ASH MEADOWS, 2007), ASH MEADOWS National Wildlife Refuge, Transportation 

Study/Environmental Assessment, Statement of Work, June 2007. 

(Andersen and Deacon, 2001), Andersen, M.E., and J.E. Deacon, Population Size of 

Devils Hole Pupfish (Cyprinodon diabolis) Correlates with Water Level. Copeia. (1): 

224-228. 

(Back, 2008). Jennifer Back, Water Rights Branch, National Park Service, Fort Collins, 

CO, personal email communication. Dated 7/31/2008. 

(Baldino, 2008), Cristi Baldino, Wildlife Biologist, Ash Meadows National Wildlife 

Refuge, personal comments on draft document, July 13, 2008. 

(Belcher, 2007). Belcher, Wayne. 2007. Personal Communication. Phone calls & email 

regarding history of ASH MEADOWS NWR and its relationship to declining water 

levels in Devils Hole. December 2007. 

(Bonstead, 2008), Leah Bonstead, Park Archaeologist, Death Valley National Park, 

telephone call, 2 April 2008. 

(Deacon and Williams, 1991), Deacon, J.E., and C.D. Williams, ASH MEADOWS and 

the Legacy of the Devils Hole Pupfish. Chapter 5 In, W.L. Minckley and J. E. Deacon 

(eds.), Battle Against Extinction: Native Fish Management in the American West. The 

University of Arizona Press. 

(Deacon, J.E., A.E. Williams, C.D. Williams, and J.E. Williams, 2007), Fueling 

population growth in Las Vegas: how large-scale groundwater withdrawal could burn 

regional biodiversity. BioScience 57:688-698.Gustafson, E.S., and J.E. Deacon. 1998. 

Distribution of Larval Devils Hole Pupfish, Cyprinodon diabolis Wales, in Relation to 

Dissolved Oxygen Concentration in Devils Hole. Final Report to the National Park 

Service, Death Valley National Park, Death Valley, California. 

(Deluca, 2001) DeLuca, T. H. 2001. Assessment of the USFS Soil Quality Standards and 

the application of those standards to the Pink Stone Environmental Impact Statement. A 

report to The Ecology Center, Inc. 

(DEVA, 2008), Archeological Survey and Consultation for the Devils Hole Site Plan, 

Death Valley National Park, Cultural Resources Project DEVA 2008A, conducted by 

Leah Bonstead, Park Archeologist, May 19, 2008. 

(Durham, 2008), Barbara Durham, Tribal Historic Preservation Officer, Timbisha 

Shoshone Tribe, telephone call, 23 January 2008. 
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References 146 

(Fisk, 2008a), Terry Fisk, Hydrologist, Death Valley National Park, email 

communication, 20 March, 2008. 

(Fisk, 2008b), Terry Fisk, Hydrologist, Death Valley National Park, email 

communication, 19 March 2008. 

(Florida Museum of Natural History, 2006). Rare Pupfish in Mojave on Brink of 

Extinction. Accessed at: http://www.flmnh.ufl.edu/fish/InNews/pupfish2006.html

(Forner, 2008), Ed Forner, Protection Division, Death Valley National Park, email 

communication, 9 November 2007. 

(Fowler, 2002), What’s In A Name? Some Southern Paiute Names for Mojave Desert 

Springs as Keys to Environmental Perception. Conference Proceeding Spring Fed 

Wetlands: Important Scientific and Cultural Resources of the Intermountain Region, May 

7-9, 2002, Desert Research Institute http://www.wetlands.dri.edu/2002/Fowler.pdf

(Gomez, 2007), Philip Gomez, “Population Will Grow to 45,000 by 2010”, Pahrump 

Valley Times, January 19, 2005. Accessed November 27, 2007 at 

http://www.pahrumpvalleytimes.com/2005/01/19/news/population.html

(Herbst and Blinn, 2003), Herbst, D.B. and D.W. Blinn, Devils Hole benthic community 

dynamics: distribution, seasonality and production. Draft report to the National Park 

Service, Death Valley National Park. January 29, 2003. 

(IPCC, 2008), Intergovernmental Panel on Climate Change, Fourth Assessment Report. 

Accessed February 23, 2008 at http://www.ipcc.ch/pdf/assessmentreport/ar4/syr/ar4_syr.pdf. 

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pworld/pupfishbtn.php

(Lyons, 2005). Temporal and spatial variation in larval Devils Hole pupfish (Cyprinodon 

diabolis) abundance and associated microhabitat variables in Devils Hole, Nevada. 

Master’s thesis. Southern Oregon University, Ashland, Oregon. 

(McKelvey, 2008), Sharon McKelvey, Wildlife Refuge Manager, ASH MEADOWS 

National Wildlife Refuge, email communication, 18 March 2008. 

(Minckley and Deacon, 1975), Minckley C.O. and J.E. Deacon, Foods of the Devils 

Hole pupfish, Cyprinodon diabolis (Cyprinodontidae). The Southwestern Naturalist.

20(1): 105-111. 
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(Manning, 2008), United States Department of the Interior, National Park Service, Death 

Valley National Park. 12 March 2008. Personal communication with Linda Manning, 

Wildlife Biologist. 

(Nalen, 2007a), Christina Nalen, Visitor Services Manager, ASH MEADOWS National 

Wildlife Refuge, personal communication, telephone call November 27, 2007. 

(Nalen, 2007b), Christina Nalen, Visitor Services Manager, ASH MEADOWS National 

Wildlife Refuge, personal communication, email 21 March, 2008.. 

 

(NDOW, 2008), Nevada Department of Wildlife, U.S. Fish and Wildlife Service, and 

National Park Service, “Devils Hole Pupfish Numbers Up,” Joint Press Release, dated 8 

October, 2008. 

(Nevada, 2007), Nevada Department of Agriculture. 2007. Nevada Department of 

Agriculture, Plant Industry Division. Noxious Weed List. Accessed at: 

http://agri.nv.gov/nwac/PLANT_NoxWeedList.htm

(Nevada Legislature, 2008), Nevada Administrative Code, Chapter 503 - Hunting, 

Fishing And Trapping; Miscellaneous Protective Measures. Accessed at: 

http://leg.state.nv.us/nac/nac-503.html

(Norton, 2006), Robert L. Norton, “Machine Design; An Integrated Approach,” 3rd ed, 

Pearson Prentice Hall, 2006, Applied to Makita Model HR4041C 12 Amp 13.7 Rotary 

Hammer with 6.6 ft-lb impact energy at 2600 BPM 

(NPS, 2002). National Park Service. 2002. Death Valley National Park General 

Management Plan. Accessed November, 2007 at: 

http://www.nps.gov/deva/parkmgmt/upload/GMP_001.pdf. 

(NPS, 2006). United States Department of the Interior, National Park Service. 2006. 

NPS Management Policies 2006. Available at: http://www.nps.gov/policy/mp2006.pdf 

(NRCS, 2001a). Natural Resources Conservation Service. 2001. Official Soil Description 

– Yermo Series. Accessed November, 2007 at: 

http://ortho.ftw.nrcs.usda.gov/osd/dat/Y/YERMO.html. 

(NRCS, 2001b). Natural Resources Conservation Service. 2001. Official Soil Description 

– Sanwell Series. Accessed November, 2007 at: 

http://ortho.ftw.nrcs.usda.gov/osd/dat/S/SANWELL.html. 

(NRCS, 2006). Natural Resources Conservation Service. 2006. Official Soil Description 

– Commski Series. Accessed November, 2007 at: 

http://ortho.ftw.nrcs.usda.gov/osd/dat/C/COMMSKI.html. 
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(Riggs and Deacon, 2002), Riggs, A.C. and J.D. Deacon. 2002. Connectivity in Desert 

Aquatic Ecosystems: The Devils Hole Story. Conference Proceedings. Spring-fed 

Wetlands: Important Scientific and Cultural Resources of the Intermountain Region, 

2002. 38pp. http://www.wetlands.dri.edu

(Shepard et al, 2000), Shepard, W.D., D.W. Blinn, R.J. Hoffman, and P.T. Kantz. 2000. 

Algae of Devils Hole, Nevada, Death Valley National Park. Western North American 

Naturalist. 60(4): 410–419. 

(Shrode and Gerkin, 1997), Shrode, J., and S. Gerking, Effects of Constant and 

Fluctuating Temperatures on Reproductive Performance of a Desert Pupfish, Cyprinodon 

n. nevadensis. Physiological Zoology. (50): 1-10. 

(SWO, 2007), Statement of Work, Devils Hole Site Plan Environmental Assessment, 

produced by Death Valley National Park, July 2007. 

(Szabo et al., 1994), Szabo, B.J., P.T. Kolesar, A.C. Riggs, I. J. Winograd, and K. R. 

Ludwig. 1994. Paleoclimatic Inferences from a 120,000-Yr Calcite Record of WaterTable Fluctuation in Browns Room of Devils Hole, Nevada. Quaternary Research. (41): 

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(Texas Tech, 2008) Museum of Texas Tech University, The Mammals of Texas – online 

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(Threloff, D., and L. Manning. 2003), Thermal Environment of the Devils Hole Pupfish 

(Cyprinodon diabolis). Draft report. 29 pp. Plus appendix. 

(USDA-ARS, 2005) USDA-ARS: Soil Resource Management. 2005. National Program 

202: Soil Resource Management Assessment Team Meeting. USDA-ARS. 

http://ars.usda.gov/sp2UserFiles/Program/202/202Assessment2004/202AssessmentRepor

tFinal.pdf Accessed March 2008. 

(USFWS, No date). U.S. Fish and Wildlife Service. No date provided. ASH MEADOWS 

National Wildlife Refuge: Refuge Habitat. Accessed November, 2007 at: 

http://www.fws.gov/desertcomplex/ashmeadows/habitat.htm. 

(USFWS, 1980), U.S. Fish and Wildlife Service, Devil’s Hole Pupfish Recovery Plan. 

U.S. Fish and Wildlife Service. Portland, Oregon. 46pp. 

(USFWS, 1990), U.S. Fish and Wildlife Service. 1990. U.S. Fish and Wildlife Service. 

1990. Recovery plan for the endangered and threatened species of ASH MEADOWS, 

Nevada. U.S. Fish and Wildlife Service, Portland, Oregon. 123 pp. 

(USFWS, 2002), U. S. Fish and Wildlife Service, Desert Bighorn Sheep of Cabeza Prieta 

NWR. Accessed at: http://www.fws.gov/southwest/refuges/arizona/cabighrn.html
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(USFWS, 2007), U.S. Fish and Wildlife Service. 2007. Ash Meadows National Wildlife 

Refuge, Refuge Wildlife. Accessed at: 

http://www.fws.gov/desertcomplex/ashmeadows/wildlife.htm

(USGS, No date). U.S. Geologic Survey. No date provided. Estimates of Ground-Water 

Discharge as Determined from Measurements of Evapotranspiration, ASH MEADOWS 

Area, Nye County, Nevada. WRIR 99-4079. Accessed November, 2007 at: 

http://pubs.usgs.gov/wri/wri994079/text/introduction.htm. 

(USGS, 1976). U.S. Geologic Survey. 1976. Effect of Irrigation Pumping on Desert 

Pupfish Habitats in ASH MEADOWS, Nye County, Nevada. Geologic Survey 

Professional Paper No. 927. U.S. Department of the Interior, Washington DC. 

(USGS, 1993). U.S. Geologic Survey. 1993. Water-Resources Data for the Devils Hole 

Area, Nye County, Nevada July 1978 – September 1988. Open File Report 90-381. U.S. 

Department of the Interior, Carson City, NV. 13 pp. 

(USGS, 1999). U.S. Geologic Survey. 1999. Summary of Hydrogeologic Controls on 

Ground-Water Flow at the Nevada Test Site, Nye County, Nevada. Accessed November, 

2007 at: http://pubs.usgs.gov/wri/wri964109/report.htm. 

(USGS, 2002). U.S. Geologic Survey. 2002. Trend Analysis of Ground-Water Levels and 

Spring Discharge in the Yucca Mountain Region, Nevada and California, 1960-2000. 

WRI Report: 02-4178. U.S. Department of the Interior, Carson City, NV. 97 pp. 

(USGS, 2004). U.S. Geologic Survey. 2004. Death Valley National Park Through Time. 

Accessed November 2007 at: http://geology.wr.usgs.gov/parks/deva/devatime.html. 

(Weiss, 2005a), Stuart B. Weiss, Ph.D., Light Environment at Devil’s Hole: Impact of 

Platform on Direct Light, February, 2005. Paper provided by Death Valley National 

Park. 

(Weiss, 2005b), Stuart B. Weiss, Ph.D., personal communication, telephone interview, 

May 15, 2008. 

(Wilcox, 2001), Small population evolution and conservation: insights from Death 

Valley pupfish. Ph.D. dissertation. Department of Environment, Population and 

Organismic Biology, University of Colorado, Boulder, Colorado. 145 pp. 

(Wilson and Blinn, 2007). Kevin Wilson and Dean Blinn. 2007. Food Web Structure, 

Energetics and Importance of Allochthonous Carbon in a Desert Cavernous Limnocrene: 

Devils Hole, Nevada. Western North American Naturalist 67(2). pp. 185-198. 

(Wolfe, 2007), Vicki Wolfe, Park Ranger-Interpretation, Visitor Profile, revised 

10/31/07.
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Glossary 150 

7.0 GLOSSARY 

Affected Environment – The existing physical, cultural or socioeconomic environment 

to be affected by a proposed action and alternatives. 

Alluvial – Sediment transported and deposited by flowing water. 

Aquifer – A formation, group of formations, or part of a formation that contains 

sufficient saturated, permeable material to yield significant quantities of water to wells 

and springs. 

Alternative – A reasonable way to fix the identified problem or satisfy the stated need 

(40 CFR 1500.2). 

Ambient – The natural surroundings of a location. 

Ambient Air – Any unconfined portion of the atmosphere: open air, surrounding air. 

Anthropogenic – Man-made. 

Archaeological Resources – Any material remains or physical evidence of past human 

life or activities, which are of archaeological interest, including the record of the effects 

of human activities on the environment that is at least 100 years old. Archaeological 

resources are capable of revealing scientific or humanistic information through 

archaeological research (NPS DO #28, Cultural Resources Management Guideline, 

1998). 

Artifacts – An object produced by human craft of archaeological or historical interest, 

including binnacles, compasses, engine order telegraphs, name boards, and builders 

plates. 

Attainment Area – An area designated to have air quality as good as or better than the 

NAAQS as defined in the Clean Air Act. An area may be an attainment area for one 

pollutant and a nonattainment area for others. 

Best Management Practices (BMP) – Methods that have been determined to be the 

most effective, practical means of preventing or reducing pollution from nonpoint 

sources. 

Carbonate rocks – A class of sedimentary rocks composed primarily of carbonate 

minerals. The two major types are limestone and dolomite, composed of calcite (CaCO3) 

and the mineral dolomite (CaMg(CO3)2) respectively. 

Cave pool – A small, isolated body of water (usually freshwater) in a chamber beneath 

the earth. 
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Glossary 151 

Compaction – To make soil dense by mechanical manipulation. 

Conductivity – The power or quality of transmitting. 

Crevasse – a deep fissure, such as that which forms the surface opening to Devils Hole 

Critical Habitat – A specific geographic area(s) that contains features essential for the 

conservation of a threatened or endangered species and that may require special 

management and protection. Critical habitat may include an area that is not currently 

occupied by the species but that will be needed for its recovery. 

Cultural Landscape – A geographic area, including both cultural and natural resources 

and the wildlife or domestic animals therein, associated with a historic event, activity, or 

person exhibiting other cultural or aesthetic values. There are four kinds of cultural 

landscapes, not mutually exclusive: historic site, historic designated landscape, historic 

vernacular landscape, and ethnographic landscape (NPS DO #28, Cultural Resources 

Management Guideline, 1998). 

Cultural Resources – An aspect of a cultural system that is valued by or significantly 

representative of a culture or that contains significant information about a culture. A 

cultural resource may be a tangible entity or a cultural practice. Tangible cultural 

resources are categorized as districts, sites, buildings, structures, and objects for the 

National Register of Historic Places and as archaeological resources, cultural landscapes, 

structures, museum objects, and ethnographic resources for National Park Service 

management purposes (NPS DO #28, Cultural Resources Management Guideline, 1998). 

Types of cultural resources include: historic properties as defined in the National Historic 

Preservation Act; cultural items as defined in the Native American Graves Protection and 

Repatriation Act; archeological resources as defined in the Archeological Resources 

Protection Act; sacred sites as defined in Executive Order 13007, Protection and 

Accommodation of Access To "Indian Sacred Sites," to which access is provided under 

the American Indian Religious Freedom Act; and collections. 

Cumulative Impacts (or Effects) – Impacts on the environment which result from the 

incremental impact of the action when added to other past, present, and reasonably 

foreseeable future actions, regardless of which agency (Federal or non-Federal) or person 

undertakes such other actions; effects resulting from individually minor, but collectively 

significant, actions taking place over a period of time. 

Designated Wilderness Area – An area designated by the United States Congress to be 

managed as part of the National Wilderness Preservation System. 

Dissolved Oxygen (DO) – Amount of free oxygen found in water; most commonly-used 

measurement of water quality. 

Diversity – The distribution and abundance of different plant and animal communities 

and species within the area covered by a land and resource management plan. 
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Disturbance – Significant alteration of habitat structure or composition, may be natural 

(e.g., fire) or human-caused events (e.g., aircraft overflight). 

Drawdown – The vertical distance the water surface elevation of a well, reservoir, etc. is 

lowered due to the removal of free water. 

Environmental Assessment (EA) – A concise public document, prepared in compliance 

with the National Environmental Policy Act, that briefly discusses the purpose and need 

for an action, alternatives to such action, and provides sufficient evidence and analysis of 

impacts to determine whether to prepare an environmental impact statement or finding of 

no significant impact (40 CFR 1508.9). 

Ecosystem – A dynamic and interrelating complex of plant and animal communities and 

their associated non-living environment. 

Endemic – A species, disease, etc. that is only found within a specific geographic region. 

Environmental Impact Statement (EIS) – A detailed written statement required by 

Section 102(2) (C) of the National Environmental Policy Act, analyzing the 

environmental impacts of a Proposed Action, adverse effects of the project that cannot be 

avoided, alternative courses of action, short-term uses of the environment versus the 

maintenance and enhancement of long-term productivity, and any irreversible and 

irretrievable commitment of resources (40 CFR 1508.11). 

Endangered Species – A species that is threatened with extinction throughout all or a 

significant portion of its range. 

Environmental Justice – The confluence of social and environmental movements, 

which deals with the inequitable environmental burden born by groups such as racial 

minorities, women, or residents of developing nations. 

Ethnographic Resources – Any site, structure, object, landscape, or natural resource 

feature assigned traditional legendary, religious, subsistence, or other significance in the 

cultural system of a group traditionally associated with it. 

Executive Order (EO) – An official proclamation issued by the President that may set 

forth policy or direction or establish specific duties in connection with the execution of 

federal laws and programs. 

Exotic – A species not historically present in an area; also known as non-native species. 

Extirpation – The elimination of a species or subspecies from a particular area, but not 

from its entire range. 
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Forage – (v) search for food or (n) grasses, small shrubs and other plant material that can 

be used as food sources for grazing animals and livestock. 

Geographic Information System (GIS) – A computer system designed to allow users to 

collect, manage, and analyze large volumes of spatially referenced information and 

associated attribute data. 

Global Positioning System (GPS) – A series of satellites and receivers used to calculate 

positions on the Earth’s surface. 

Groundwater – The supply of fresh water found underground, usually in aquifers, which 

supply wells and springs.

Habitat – Suite of existing environmental conditions required by an organism for 

survival and reproduction. The place where an organism typically lives. 

Habitat Restoration – Management emphasis designed to move ecosystems to desired 

conditions and processes, and/or to healthy ecosystems. 

Hazardous Waste/Materials – Any unusable material as defined by applicable law that 

is liquid, solid or gaseous, which if improperly stored, treated, transported, disposed or 

otherwise managed, may pose a substantial present or potential hazard to human health or 

the environment due to its quantity, concentration, physical characteristic, or chemical 

characteristic. Unlabeled containers are assumed to be hazardous waste until proven to 

be otherwise. 

Historic Structure – A constructed work, usually immovable by nature or design, 

consciously created to serve some human activity (NPS DO #28, Cultural Resources 

Management Guideline, 1998). 

Invasive Species – An alien species (nonnative to the ecosystem) whose introduction 

does or is likely to cause economic or environmental harm or harm to human health. 

Karst – A three-dimensional landscape shaped by the dissolution of a soluble layer or 

layers of bedrock, typically resulting in the development of caves and cave systems. 

Lacustrine – Of or pertaining to a lake. 

Migration – The seasonal movement from one area to another and back. 

Monitoring – The process of collecting information to track changes of selected 

parameters over time. 

Minority – Individual(s) who are members of the following population groups: 

American Indian or Alaskan Native; Asian or Pacific Islander; African American, not of 

Hispanic origin; or Hispanic. 
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Minority Population – Identified where either the affected area’s minority population 

exceeds 50 percent or the affected area’s minority population percentage is meaningfully 

greater than the minority population percentage in the general population or other 

appropriate unit of geographic analysis. 

Mitigation – Methods or actions taken to improve site conditions by limiting, reducing or 

controlling adverse impacts to the environment. 

Museum Collections – Assemblage of objects, works of art, historic documents, and/or 

natural history specimens collected according to a rational scheme and maintained so 

they can be preserved, studied, and interpreted for public benefit. Museum collections 

normally are kept in park museums, although they may also be maintained in 

archaeological and historic preservation centers (NPS DO #28, Cultural Resources 

Management Guideline, 1998). 

National Ambient Air Quality Standards (NAAQS) – Standards established by the 

Environmental Protection Agency (EPA) that apply for outdoor air throughout the 

country. Primary standards are designed to protect human health, with an adequate 

margin of safety, including sensitive populations such as children, the elderly, and 

individuals suffering from respiratory disease. The NAAQS represent maximum air 

pollutant standards that the EPA set under the Clean Air Act for attainment by each state. 

National Register of Historic Places (National Register) – A register of districts, sites, 

buildings, structures, and objects important in American history, architecture, 

archaeology, and culture, maintained by the Secretary of the Interior under authority of 

Section 2(b) of the Historic Sites Act of 1935 and Section 101(a)(1) of the National 

Historic Preservation Act of 1966, as amended. 

National Environmental Policy Act (NEPA) – Requires all agencies, including 

National Park Service, to examine the environmental impacts of their actions, incorporate 

environmental information, and use public participation in the planning and 

implementation of all actions. Federal agencies must integrate NEPA with other planning 

requirements, and prepare appropriate NEPA documents to facilitate better environmental 

decision making (40 CFR 1500). 

Native – A species that historically occurs in an area or one that was not introduced 

(brought) from another area. 

Nonattainment area – An area that does not meet one or more of the NAAQS for the 

criteria pollutants designated in the Clean Air Act. 

 

Palustrine – Relating to a system of inland, non-tidal wetlands characterized by the 

presence of trees, shrubs, and emergent vegetation (vegetation that is rooted below water 

but grows above the surface). 
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Permeability – Formations that transmit fluids readily, such as sandstones, are described 

as permeable and tend to have many large, well-connected pores. 

pH – A numerical indicator of the acidity or alkalinity of a substance; ranges from 0.0 

(acidic) to 14.0 (basic or alkaline); pure water is neutral, with a pH of 7.0. 

Photic zone – The water depth sufficiently exposed to sunlight for photosynthesis to 

occur 

Porosity – a measure of the void spaces in a material. 

Runoff – Non-infiltrating water entering a stream or other conveyance channel shortly 

after a rainfall. 

Sediment – Any finely divided organic and/or mineral matter derived from rocks or 

biological sources that have been transported and deposited by water or air. 

Sedimentation – The process of depositing sediment from suspension in water. 

Seeding – The establishment of a temporary or permanent vegetative cover on disturbed 

areas by planting seed. 

Silt Fence – A temporary barrier, consisting of a filter fabric stretched between 

supporting posts with the bottom entrenched in the soil, used to trap sediment. 

Soil Erosion – The removal and loss of soil by the action of water, ice, gravity, or wind. 

Solvent – A substance (generally liquid) that another substance dissolves into to make a 

solution. 

State Historic Preservation Officer (SHPO) – The official within each state, authorized 

by the state at the request of the Secretary of the Interior, to act as a liaison for purposes 

of implementing the National Historic Preservation Act. 

Stilling well – A monitoring device used for water level measurements at Devils Hole, in 

which a chamber is connected to the flow channel by a small inlet. Waves and surges in 

the main flow stream will not appear in the well due to the small-diameter inlet. The 

liquid surface in the well will be quiet, but will follow all of the steady fluctuations of the 

open channel. The liquid level in the well is measured to determine the flow in the main 

channel.

Stormwater – Water discharges generated by runoff from land and impervious areas 

such as paved streets, parking lots, and building rooftops during rainfall and snow events. 

Storm water often contains pollutants in quantities that could adversely affect water 

quality. 
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Stretch fault – A reverse fault developed as a result of shear in the middle limb of an 

overturned fold. 

Structure (in terms of cultural resources) – A constructed work, usually immovable by 

nature or design, consciously created to serve some human activity (e.g., buildings, 

monuments, dams, roads, railroad tracks, canals, millraces, bridges, tunnels, locomotives, 

forts and associated earthworks, Indian mounds, ruins, fences, and outdoor sculpture). In 

the National Register program, “structure” is limited to functional constructions other 

than buildings (NPS DO #28, Cultural Resources Management Guideline, 1998). 

Take – In the context of the Endangered Species Act, to“take” is to harass, hunt, capture, 

or kill, or attempt to harass, hunt, capture or kill any marine mammal (MMPA), or to 

harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect any listed species 

(ESA). 

Threatened Species – A species that is likely to become an endangered species within 

the foreseeable future throughout all or a significant portion of its range. 

Topsoil – The topmost layer of soil, usually containing organic matter. 

Traditional Cultural Property – Property affiliated with traditional religious and 

cultural importance to a Native American Tribe or Native Hawaiian group. These 

properties are eligible for the National Register of Historic Places. 

Turbidity – Measure of the extent to which light passing through water is reduced due to 

suspended matter. The turbidity is caused by the content and shape of the suspended 

materials. 

Wetlands – Areas that are inundated or saturated with surface or groundwater at a 

frequency and duration sufficient to support a prevalence of vegetation typically adapted 

for life in saturated soil, including swamps, marshes, bogs, and other similar areas. 
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Appendix A-1 

APPENDIX A: PROJECT COMPONENT DESIGNS 
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Appendix A-2 

Figure A-1. No Action Alternative (existing site layout) 

 
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Appendix A-3 

Figure A-2. Alternative A (Preferred Alternative)—Site Schematic 

 
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Figure A-3. Alternative A—Fencing, Visitors Tunnel and Platform 

Appendix 
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Appendix A-5 

Figure A-4. Alternative A—Ships Ladder 
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Appendix A-6 

Figure A-6: Individual platform section, 5 ft long, 40 lbs 

Figure A-5: Platform Assembly—Alternative A 
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Appendix A-7 

Figure A-7: East wall anchors, (left) the platform section being deployed and (right) 

the deployed platform—Alternative A

Figure A-8: Connection of platform—Alternative A 
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Appendix A-8 

Figure A-10: Diagram showing the built-in measuring system—Alternative A 

Figure A-9: Location of measuring rods—Alternative A 
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Appendix A-9 

TWO PAN AND TILT

SECURITY CAMERAS (#1 & #2)

TWO INTERPRETIVE CAMERAS

ONE UNDERWATER LENS 

CAMERA

ONE OBSERVATION 

PLATFORM CAMERA

NOTE: FINAL LOCATION 

OF CAMERAS TBD WITH 

NPS APPROVAL

(#3)

(#4)

(#5)

(#6)

Figure A-11. Camera Configuration—Alternative A
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Appendix A-10 

Figure A-12. Alternative B—Site schematic 
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Figure A-13. Alternative B—Fencing, gate, and Access path to Visitors Platform 

Appendix 
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Appendix A-12 

Figure A-14. Alternative B—Existing ladder with added handrail 
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Appendix A-13 

Figure A-16: Hinged monitoring platform, bolted to east wall—Sectional views—

Alternative B 

Figure A-15: Hinged monitoring platform, bolted to the east wall—Alternative B 
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Appendix A-14 

TWO PAN AND TILT

SECURITY CAMERAS (#1 & #2)

TWO INTERPRETIVE CAMERAS

ONE OBSERVATION 

PLATFORM CAMERA

NOTE: FINAL LOCATION 

OF CAMERAS TBD WITH 

NPS APPROVAL

(#3)

(#4)

(#5)

Figure A-17. Camera Locations—Alternative B 
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Appendix B-1 

APPENDIX B: AGENCY CONSULTATIONS 
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Appendix B-2 
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Appendix B-3 
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Appendix B-4 
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Appendix B-5 
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Appendix B-6 
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Appendix B-7 
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Appendix B-8 
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Appendix B-9 
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Appendix B-10 
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Appendix B-11 
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Appendix B-12 
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Appendix B-13 
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Appendix C-1 

APPENDIX C: SPECIES OF CONCERN IN ASH MEADOWS 

NWR 
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Appendix 

Species of Concern at Ash Meadows NWR 

Common Name Scientific Name USFWS BLM Status 

NV 

Natural 

Heritage 

Plants 

Ash Meadows blazing star Mentzelia leucophylla T S CE at-risk Amargosa niterwort Nitrophila mohavensis E S CE at-risk Ash Meadows milk-vetch Astragalus phoenix T S CE at-risk Ash Meadows sunray Enceliopsis nudicaulis corrugata T S CE at-risk Spring-loving centaury Centaurium namophilum T S CE at-risk Ash Meadows gumplant Grindelia fraxino-pratensis T S CE at-risk Ash Meadows ivesia Ivesia kingii var. eremica T S CE at-risk Alkali mariposa lily Calochortus striatus N, C at-risk Ash Meadows lady’s tresses Spiranthes infernalis at-risk Tecopa birdsbeak Cordylanthus tecopensis N, C at-risk White bear poppy Arctomecon merriamii N at-risk Darin buckwheat Eriogonum concinnum at-risk Parish’s phacelia Phacelia parishii at-risk Death Valley sage Salvia funereal at-risk Death Valley blue-eyed grass Sisyrinchium funereum at-risk St. George blue-eyed grass Sisyrinchium radicatum at-risk 

Invertebrates 

Amargosa naucorid Pelecoris biimpressus biimpressus Amargosa naucorid Pelocoris shoshone amargosus at-risk Ash Meadows naucorid Ambrysus amargosus T S at-risk Warm Springs naucorid Ambrysus relictus 
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Appendix 

Devil’s Hole warm spring riffle beetle Stenelmis calida calida N at-risk Unnamed riffle beetle Microcylloepus similis SS Death Valley June beetle Polyphylla erratica SS Death Valley agabus diving beetle 

Agabus rumppi watch 

Ash Meadows alkali skipper Pseudocopaeodes eunus alinea N at-risk Ash Meadows pebble snail Pyrgulopsis erythropoma PS, U at-risk Crystal Springs snail Pyrgulopsis crystalis PS, U at-risk Distal-gland springsnail Pyrgulopsis nanus PS, U at-risk Elongate gland springsnail Pyrgulopsis isolatus PS, U at-risk Fairbanks Spring snail Pyrgulopsis fairbanksensis PS, U at-risk Median-gland Nevada spring snail Pyrgulopsis pisteri PS, U at-risk Oasis Valley springsnail Pyrgulopsis micrococcus N PS, U at-risk Amargosa tryonia Tryonia variegata N PS, U at-risk Minute tryonia Tryonia ericae PS, U at-risk Point of Rocks tryonia Tryonia elata PS, U at-risk Sportinggoods tryonia Tryonia angulata PS, U at-risk Virile Amargosa snail Undescribed 

Fish 

Devil’s Hole pupfish Cyprinodon diabolis E S PS, P, E at-risk Warm Springs pupfish Cyprinodon nevadensis pectoralis E S PS, P, E at-risk Ash Meadows Amargosa pupfish Cyprinodon nevadensis mionectes E S PS, P,T at-risk Ash Meadows speckled dace Rhinichthys osculus nevadensis E S PS, P,E at-risk 

Reptiles 

Western banded gecko Coleonyx variegatus PS Great Basin collared lizard Crotaphytus bicinctores PS Desert iguana Dipsosaurus dorsalis PS watch Long-nosed leopard lizard Gambelia wislizenii PS 
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Appendix 

Desert horned lizard Phrynosoma platyrhinos PS Chuckwalla Sauromalus ater N PS watch Desert night lizard Xantusia vigilis vigilis PS Desert tortoise Gopherus agassizii T S PS at-risk 

Birds (^breeding, +prob. breeding) 

American avocet+ Recurvirostra americana PS American white pelican Pelecanus erythrorhynchos P PS, P watch Arizona Bell’s vireo^ Vireo bellii arizonae P PS, P watch Bald eagle Haliaeetus leucocephalus Delisted S PS, P, E at-risk Black-necked stilt^ Himantopus mexicanus PS Black tern Chlidonias niger N P watch Black phoebe^ Sayornis nigricans PS Blue grosbeak^ Guiraca caerulea ST, P Brewer’s sparrow^ Spizella breweri PS, P, S California black rail Laterallus jamaicensis coturniculus Species of 

Concern 

Canvasback Aythya valisineria PS Cinnamon teal^ Anas cyanoptera PS Clark’s grebe Aechmorphorus clarkia PS Common loon Gavia immer PS, P watch Cooper's hawk Accipiter cooperii ST, P Costa’s hummingbird^ Calypte costae PS Crissal thrasher^ Toxostoma crissale N PS, P watch Eared grebe+ Podiceps nigricollis PS Ferruginous hawk Buteo regalis N PS, P at-risk Forster’s tern Sterna forsteri PS Franklin’s gull Larus pipixcan PS Golden eagle+ Aquila chrysaetos N P watch 
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Appendix 

Gray flycatcher Empidonax wrightii ST, P Least sandpiper Calidris minutilla PS LeConte’s thrasher^ Toxostoma lecontei N,C PS, P at-risk Lewis' woodpecker Melanerpes lewis N PS, P watch Loggerhead shrike^ Lanius ludovicianus N PS, P, S watch Long-billed curlew Numenius americanus N PS, P watch Long-billed dowitcher Limnodromus scolopaceus PS Long-eared owl Asio otus N P watch Lucy’s warbler^ Vermivora luciae N PS, P watch Northern pintail Anas acuta PS Olive-sided flycatcher Contopus borealis PS, P watch Osprey Pandion haliaetus P Peregrine falcon Falco peregrinus Delisted N PS, P, E at-risk Phainopepla^ Phainopepla nitens N PS, P at-risk Pinon jay Gymnorhinus cyanocephalus N PS, P watch Prairie falcon+ Falco mexicanus N P watch Redhead^ Aythya americana PS Red-naped sapsucker Sphyrapicus nuchalis N ST, P watch Red-necked phalarope Phalaropus lobatus PS Rufous hummingbird Selasphorus rufus PS Sage sparrow^ Amphispiza bellii PS Sage thrasher Oreoscoptes montanus P Short-eared owl Asio flammeus N PS, P watch Snowy egret Egretta thula PS Southwestern willow flycatcher Empidonax traillii extimus E S PS, P, E at-risk Swainson’s hawk Buteo swainsoni N PS, P watch Verdin^ Auriparus flaviceps PS Virginia’s warbler Vermivora virginiae PS Western burrowing owl^ Athene cunicularia hypugea N,C PS, P watch 
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Appendix 

Western grebe Aechmorphorus occidentalis PS Western least bittern Ixobrychus exilis hesperis N PS, P at-risk Western snowy plover Charadrius alexandrinus nivosus N PS, P watch Western yellow-billed Cuckoo Coccyzus americanus occidentalis C S P at-risk White-faced ibis Plegadis chihi P PS, P watch White-throated swift+ Aeronautes saxatilis PS Willet Catoptrophorus semipalmatus PS Yellow-breasted chat^ Icteria virens N P watch Yuma clapper rail Rallus longirostris yumanensis E - PS, P at-risk 

Mammals 

Pallid bat Antrozous pallidus N,C P watch Silver-haired bat Lasionycteris noctivagans N watch Hoary bat Lasiurus cinereus N PS watch Western red bat Lasiurus blossevillii N PS, P at-risk Spotted bat Euderma maculatum S PS, P,T at-risk Western small-footed myotis Myotis ciliolabrum N,C PS watch Townshend’s big eared bat Corynorhinus townsendii N,C PS, P, S at-risk Brazilian free-tailed bat Tadarida brasiliensis N P watch Ash Meadows montane vole Microtus montanus nevadensis N PS, P, S at-risk Desert kangaroo rat Dipodomys deserti PS watch Desert pocket mouse Chaetodipus pencillatus PS at-risk Brush mouse Peromyscus boylei PS Kit fox Vulpes macrotis PS, P watch Ringtail Bassariscus astutus PS Mule deer Odocoileus hemionus PS Desert bighorn sheep Ovis canadensis nelsoni PS 
U.S. National Park Service Env

Death Valley National Park 

Appendix Abbreviations: USFWS: E = endangered; T = threatened. BLM: S = Nevada special status species; N = Nevadspecies (designated Sensitive by State Office); P = proposed Nevada special status species (designated proposed Office; C = California special status species. State: PS = priority species; ST = stewardship species; P = state prendangered; CE = critically endangered plant; T = state threatened; S = sensitive; U = state unprotected. NV Natsensitive species; at-risk = At-Risk Tracking List (some level of imperilment); watch = Watch List (taxa could future) Source: USFWS, Recovery Plan for the Endangered and Threatened Species of Ash Meadows 1990; Nevada Natural Herit

NDOW, Nevada Wildlife Action Plan, 2006; Otis Bay, Inc. and Stevens Ecological Consulting, LLC, Ash Meadows GeomAssessment, 2006. 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Appendix D-1 

APPENDIX D: DEVILS HOLE PLANT SPECIES 
U.S. National Park Service Environmental Assessment 

Death Valley National Park Devils Hole Site Plan 

Appendix D-2 

Devils Hole Plant Species List 

Species Name Common Name 

Ambrosia dumosa white bursage 

Amphipappus fremontii var. fremontii chaff bush 

Atriplex confertifolia shadscale 

Atriplex hymenelytra desert holly 

Aristida purpurea purple threeawn 

Brickellia atractyloides spearleaf brickellbush 

Cheilanthes parryi Parry's lip-fern 

Chorizanthe brevicornu var. brevicornu brittle spineflower 

Chorizanthe rigida devil's spineflower 

Cryptantha decipiens gravelbar cryptantha 

Cryptantha racemosa bushy cryptantha 

Descurainia pinnata ssp. glabra, western tansymustard 

Echinocactus polycephalus var. polycephalus cottontop cactus 

Echinocereus engelmannii Engelmann's hedgehog cactus 

Ephedra funereal Death Valley jointfir 

Eriogonum inflatum desert trumpet 

Eriogonum trichopes little desert buckwheat 

Erioneuron pulchellum fluffgrass 

Eucnide urens rock nettle 

Galium stellatum var. eremicum star-flowered bedstraw 

Krameria erecta littleleaf ratany 

Langloisia setosissima ssp. punctata lilac sunbonnet 

Larrea tridentate creosote bush 

Lepidium fremontii var. fremontii desert pepperweed 

Lycium andersonii Anderson's desert-thorn 

Lycium pallidum var. oligospermum rabbit thorn 

Mammillaria tetrancistra common fishhook cactus 

Nicotiana obtusifolia desert tobacco 

Opuntia basilaris var. basilaris Trelease's beavertail pricklypear 

Opuntia echinocarpa silver cholla 

Plantago ovatum wooly plantain 

Pleurocoronis pluriseta arrow weed 

Schismus arabicus Arabian schismus 

Sphaeralcea ambigua var. ambigua desert mallow 

Stephanomeria pauciflora brownplume wirelettuce 

Tidestromia oblongifolia Arizona honeysweet 

Xylorhiza tortifolia Mojave aster