Geologic Resources Management

Program Guidance

Achieving Program Objectives

1. Preserve Geologic Resources and Address their Interaction with Other Park Resources

The fundamental NPS policy is the preservation of resources in their natural condition whenever possible, including geologic resources. As used in this section, the term "geologic resources" includes both geologic features and geologic processes. NPS managers are frequently faced with the issue of how to manage geologic features that are threatened by human influences or geologic processes. How a park resolves this interaction should be determined by the park’s enabling legislation, other legal mandates, and park planning documents.

Fragile geologic resources within parks (such as soft sandstone, natural arches, geothermal features and formations, or mineral crystals) can be protected from human damage by educating the public and/or by isolating the feature from human intervention. For example, it may be necessary in some cases to restrict public access to a particularly sensitive or fragile geologic resource or some aspect of the resource. Some geologic resources or portions of them may be managed exclusively for research, with access limited to approved research personnel. As visitation continues to increase servicewide, additional features may need protection and those already under protection may require more stringent protection.

Because of their critical role in ecosystem health, natural processes should also be protected. In most cases such processes should be allowed to proceed unimpeded. Surficial geologic processes, for example, determine in part the locations and layouts of communities (including prehistoric ones), the spatial distributions of habitats and species, and even the locations of some national parks, such as Grand Canyon, Great Sand Dunes, and Everglades. These processes are responsible for maintaining habitat and species diversity by ensuring dynamic physical conditions, and for destroying facilities that are inappropriately sited. The unimpeded continuation of these processes is necessary for maintaining habitats and conserving species dependent upon these habitats, such as in the cases of cranes that need frequently flooded zones for nesting or thermophilic bacteria that survive only in active hot springs.

Protection of geologic features from natural processes may be necessary at times in the interest of public safety or preserving the feature itself. When necessary and possible, natural processes can be influenced or controlled. For example, rivers can be controlled by a variety of structures. Natural patterns of coastal change can be modified by human intervention through armoring or beach nourishment. However, it is important to be aware that attempting to control natural processes may have short-term success, but dire long-term ecological consequences.

Specific management techniques for particular geologic resources – both features and processes – should be applied on a park-specific and resource-specific basis, and reviewed periodically for their appropriateness or effectiveness.

2. Systematically Inventory and Monitor Geologic Resources and Manage Geologic Databases

An inventory of a park’s geologic resources forms the basis for a sound resource management program. Bedrock and surficial geologic maps provide the foundation for studies of groundwater, geomorphology, and soils. They describe the underlying physical habitat of many natural systems and are an integral component of the inventories stipulated by the Natural Resources Inventory and Monitoring Program guidance and the 1997 NPS Strategic Plan. A working understanding of geologic maps and technical reports can assist park management in making decisions on issues as diverse as location of undiscovered cultural features, an area’s fire history, and threatened and endangered species habitat. This information is essential to the preservation and protection of fragile resources such as fossils, cave and karst features, and mineral crystals. Additionally, this geologic knowledge is helpful for avoiding areas with hazards such as faults, rockfalls, landslides, and unstable substrata, thereby enhancing protection of park structures, roads, and visitors. Presented below is an overview of inventory and monitoring as they apply to geologic resources. (See Natural Resource Inventory and Monitoring in this Reference Manual for further information).

Geologic resource inventory

A geologic resource inventory consists of four components:

1. A bibliography of geologic literature and maps called GeoBib, available through the Natural Resources Program Center. This bibliography is park specific and provides a database of references from the U.S. Geological Survey (USGS), state geological surveys or minerals management agencies, geological societies, and academic institutions.
2. An evaluation of geologic maps, resources, and issues. This evaluation is generally conducted on site by park and Natural Resource Program Center staff along with USGS, state geological survey, or park geology academic experts.
3. A digital geologic map of the park and surrounding area. An accurate geologic map and explanatory text is the single most important component of a resource inventory. Many parks and regions still have only been mapped at a small regional scale. Acquiring a map at 1:24000 scale or compiling such a map is a high priority of the NPS.
4. A report with basic geologic information. This report commonly summarizes the exploration history, geology, unique features, paleontology, disturbed lands, available geologic data, geologic hazards, and other issues needed to describe the basic geologic resources of each park. Park or volunteer staff, the Natural Resource Program Center, the USGS or state survey, or an academic institution may prepare such a report.

The Natural Resource Program Center, through the Geologic Resources Division and the Natural Resource Information Division’s Inventory and Monitoring Program, conducts geologic resource inventories for natural area parks. Scheduling for individual parks can be obtained by contacting either of these offices.

Geologic resource monitoring

Observation and monitoring provide baseline data needed to manage the park and to protect the geologic resource. Geologic resources subject to deterioration, movement, growth, or other types of changes should be monitored. For example, parks should monitor fragile cave resources (to track growth or deterioration due to human impact), movement along faults, movement of slumps or landslides, rates of erosion or change of barrier islands, movement of glaciers, changes in fluvial (river) systems, and movement of dunes. After a determination is made as to what geologic features and processes should be subject to observation and monitoring, these activities should be conducted on a routine basis.

Inventories and maps of paleontological and mineral collecting sites should be kept current so that activity on those sites can be monitored and those resources can be adequately protected. The location and condition of other fragile features should be noted so they can be protected as well.

Either park staff or outside groups or agencies, such as academic institutions, the USGS, or state surveys, may monitor park geologic resources. At Hawaii Volcanoes National Park, the USGS observes changing activity via the Hawaiian Volcano Observatory. Similarly, Yellowstone National Park has a long history of monitoring its geysers and geothermal activity. In some cases, volunteers from the scientific community may be used to monitor on-going phenomena. It is important that whoever does the monitoring have direct scientific involvement in the design (and review) of all monitoring protocols and in the analysis of the data at regular intervals. Annual reports on monitoring progress or results should be provided to the park for research, management, or interpretive needs. In addition, the monitoring should meet the requirements described in Natural Resource Inventory and Monitoring in this Reference Manual. The Natural Resource Program Center is available to assist parks in establishing a geologic resource monitoring program.

3. Integrate Geologic Resource Management into the Planning Process

Ecosystem planning involves the integration of the biological, human, and geologic systems, and an understanding that the geologic system is the foundation on which the biotic and human systems are constructed. To be successful, NPS planning efforts need to do more than include a "geology" section that simply describes the rocks in the park. Planning documents should convey the park's understanding, both spatially and temporally, of geologic processes and features. Planning documents should link the geologic environment to landscape-scale processes and characteristics, to operational decisions, and to park land use decisions, and include predictions about the impact to the geologic system from land management actions.

The individual park statement for management and general management plan may have identified areas for consideration for geologic resource management. However, the most effective planning tool for dealing with geologic resources should be the resource management plan. When warranted, a resource management plan can have an appended action plan for geologic resource management.

4. Mitigate or Restore Geologic Resources Disturbed by Human Activity

It is NPS policy to reestablish natural functions and processes in human-disturbed natural systems in parks unless otherwise directed by Congress. Impacts to geologic resources resulting from human disturbances include but are not limited to physical or chemical changes to soils, unique geologic features, and changes to hydrologic patterns, erosion rates, and sedimentation. NPS efforts to restore or mitigate damages to geologic resources should include soil-geomorphic, chemical, and biologic functions and processes that were or are affected by modern human activities, so that these resources will be reintegrated with the surrounding natural ecosystem functions and processes.

For detailed guidance in planning and implementing a restoration project, see Disturbed Land Restorationin this Reference Manual.

5. Coordinate Scientific Research and Collecting

The scenic grandeur of the geologic resources preserved in the National Park System are of international renown and cover a range of features and geologic processes unmatched by any other park system in the world. Parks should facilitate geologic research in parks, since such research is vital to the understanding and continued advancement of geology in general as well as to the understanding of the geology of an individual park.

The NPS primarily coordinates and facilitates geological research by other organizations, including colleges and universities, the USGS, state geological surveys, and private societies such as the Geological Society of America. Managers and staff can support research by encouraging educational institutions and research organizations to study park resources and by helping researchers identify past and ongoing research in the park. Park managers and staff should consider all geological research requests that meet geologic scientific research criteria.

All scientific research and collection in park units must be conducted pursuant to the requirements of 36 CFR § 2.5 and NPS scientific research and collecting permits. These permits are available in DO 74 Studies and Collecting and in Research Administration and Collections in this Reference Manual. More information is also available in Paleontological Resources Management in this document.

6. Enhance Geologic Education and Interpretation

Interpretation of geologic resources is a significant part of the interpretation and education program in many parks and should be considered a part of geologic resources management. Interpretation can be an effective management tool to meet the NPS mission goals for resource protection, visitor understanding of park significance, and support for resource preservation. Resource managers and geologists can help a park's interpretation program by providing up-to-date geologic information, site-specific details, and information on current critical management issues.

Geologic theories are continuously tested and refined, and over time there has been substantial change in our understanding of earth systems. If a park's interpretive materials are more than 15 years old, they probably need to be reviewed and updated to reflect current thinking.

Each park determines the geologic resources to be interpreted during development of its comprehensive interpretive plan. Resource managers should contribute natural resource and geology topics to the comprehensive interpretive plan's long-range plan, annual work plan, theme statements, and visitor experience statements.

Creating geological interpretation materials for the public requires a unique combination of technical capability and communication skills. Development teams for interpretive plans and programs on geologic resources should consider involving geologists as subject matter experts. The NPS has professional geologists working in some parks and regions and in the Natural Resource Program Center (see Roles & Responsibilities, below). Geologists from the USGS, universities, museums, and state surveys may also be consulted. Geology educators from organizations like the National Earth Science Teachers Association or the Geological Society of America's Partners for Education Program could also be valuable contributors.

Geologic interpretation and education programs in parks should be non-consumptive. Unlike living resources, rocks, fossils, crystals, and mineral specimens do not reproduce nor can they be recreated. Geologic material, like other park resources, must not be removed or destroyed. (The only exceptions to this general prohibition are explained in Coordinate Scientific Research and Collecting, above, and below in Manage Recreational Collecting.) Also, a great deal of scientific information can be learned from the original location and orientation of geologic materials, so in-house collect-and-return programs are discouraged. Alternatively, parks should be encouraged to provide information on other public lands that offer collection experiences, and on museum and university collections that hold park specimens.

Generally, parks should not grant educational collecting permits for geologic samples. Introductory geology courses and K-12 programs do not need park specific materials. At this level, even for units on park geology, educators can use non-park hand samples or commercial rock sets and nonconsumptive activities. Proposals for more advanced geologic study requiring park specific samples should require an application for a research permit and an evaluation of scientific merit. (See the discussion on scientific research permits above in Coordinate Scientific Research and Collecting.)

Geographic features that may have ethnographic significance for groups traditionally associated with parklands should also be interpreted in a manner that is sensitive to the groups’ religious or other beliefs. Interpretation of ethnographically significant geographic resources requires ongoing consultation between the park and the traditionally associated group, as well as consultation with a qualified cultural anthropologist.

7. Improve Understanding of Geologic Hazards

The geologic processes that formed the spectacular landscapes of many national parks remain active today, and can be hazardous to park visitors, staff, infrastructure, and neighbors. Potentially hazardous processes include volcanic eruptions and other geothermal related features, earthquakes, landslides and other slope failures, mudflows, sinkhole collapses, snow avalanches, flooding, glacial surges and outburst floods, tsunamis, and shoreline movements. Attempts to prevent or control these processes are generally expensive, often futile, and typically have harmful impacts that can outweigh their benefits. However, lives and money can be saved by acquiring scientific information about the nature of a park’s geologic hazards and the degree of risk they represent, then incorporating that information into the planning process and other park management decisions so that exposure of people and facilities to hazards is minimized.

Through geologic mapping and analysis of deposits and landforms, geologists can reconstruct the history of an area for many millions of years, and find evidence of the geologic forces that created today’s landscape. The locations where hazardous geologic processes occurred in the past are often the places that are most likely to be affected by geologic hazards in the future. Some obvious examples include fault scarps, zones of rock rubble (talus) at the bases of cliffs, volcanic deposits, and avalanche chutes. Less obvious geologic processes also have the potential to affect the human environment. Examples include hidden fault zones, swelling clays and soils, and areas subject to infrequent though catastrophic slope failure, subsidence, or flooding.

The timing of past hazardous activity must also be carefully considered. An event that has recurred frequently in the past few thousand years may be more likely to occur again in our lifetimes, whereas activity that last happened millions of years ago in a given location is generally less likely to occur there again. For most types of hazards, large destructive events are less frequent than smaller, less damaging activity. Small events may serve to release geologic stress, for example, by allowing a fault to slip in small increments or a volcano to eject molten rock rising from deep in the earth in a series of minor eruptions. Long periods of quiescence at places that have a history of activity in the recent geologic past may be ominous rather than reassuring, indicating buildup of geologic stress that must eventually be released in a catastrophic event.

Since the magnitude or danger of a potential geologic hazard is not always obvious to the untrained eye, it is important that geoscientists be involved in the early phases of land management planning and project planning.The role of the scientist is to provide the best available information to enable park management to make informed decisions. Integrating geologic hazards information into the NPS planning process will reduce the long-term cost of park projects, eliminate the time and cost of repairing unanticipated damage, and possibly save lives.

The following management actions can significantly reduce the threat from geologic hazards:

• Obtain the best available information from qualified scientists about the type of geologic hazards that could affect the park, the potential magnitude and frequency of hazards, and locations where the hazards pose the greatest threat. This information can often be displayed on a hazard map that can be digitized and incorporated into the park GIS. It can be obtained through the U.S. Geological Survey, state geological surveys, local universities, or technical assistance requests to the Geologic Resources Division.
• Assess the risk at developed locations by considering the presence and nature of the hazard, the value of the development, and vulnerability of the development to that specific hazard.
• Avoid placing or concentrating new visitor facilities, buildings, and other infrastructure at sites most vulnerable to geologic hazards, through the park planning and environmental review process.
• Monitor conditions that may precede or warn of impending geologic hazards using the best available scientific methodology, and ensure that procedures are in place to convey monitoring information to park management.
• Develop a plan for effective geologic hazards response, in cooperation with geologists, other hazards specialists, and local, state, and federal emergency response officials, as appropriate.
• Educate park visitors and neighbors about geologic hazards and appropriate hazard response.

NPS Management Policies (2001) contain the following direction for managing geologic hazards.

4.8.1.3 Geologic Hazards

Naturally-occurring geologic processes, which the NPS is charged to preserve unimpaired, can be hazardous to humans and park infrastructure. These include earthquakes, volcanic eruptions, mudflows, landslides, floods, shoreline processes, tsunamis, and avalanches. The Service will work closely with specialists at the U.S. Geological Survey and elsewhere, and with local, state, and federal disaster management officials, to devise effective geologic hazard identification and management strategies. Although the magnitude and timing of future geologic hazards are difficult to forecast, park managers will strive to understand future hazards and, once the hazards are understood, minimize their potential impact on visitors, staff, and developed areas. Before interfering with natural processes that are potentially hazardous, superintendents will consider alternatives such as closing an area to visitors or relocating facilities.

The Service will try to avoid placing new visitor and other facilities in geologically hazardous areas. Superintendents will examine the feasibility of phasing out, relocating, or providing alternative facilities for park developments subject to hazardous processes, consistent with other sections of these management policies.

8. Manage Recreational Collecting

NPS regulations at 36 CFR § 2.1(a) and § 2.5(a) generally prohibit recreational collecting, rockhounding, and gold panning of rocks, minerals, and paleontological specimens in all units of the National Park System. Violators of this prohibition are subject to criminal penalties.

However, there are two exceptions to the general prohibition. Limited recreational gold panning is allowed in the Whiskeytown unit of the Whiskeytown-Shasta-Trinity National Recreation Area, in accordance with regulations at 36 CFR § 7.91.

The second exception involves some Alaska park units, where surface collection by hand (including hand-held gold pans) and for personal recreational use only, of rocks and minerals (except for silver, platinum, gemstones, and fossils) is allowed in accordance with 36 CFR § 13.20(c). (Since 36 CFR § 13.20(c) does not apply to Klondike Gold Rush National Historical Park, Sitka National Historical Park, the former Mt. McKinley National Park, Glacier Bay National Monument, and Katmai National Monument, recreational collecting in these park units is prohibited by the general regulations at 36 CFR Part 2). In the Alaska parks where collecting is allowed, 36 CFR § 13.20(c) prohibits collection methods that may result in disturbance of the ground surface, such as the use of shovels, pickaxes, sluice boxes, and dredges. Also, if any person finds that such collecting would have a significant adverse impact on park resources or visitor enjoyment of such resources, 36 CFR § 13.20(d) requires the park superintendent to prohibit the gathering or to otherwise restrict the collecting of these items.

Although no permit is required for personal collecting in these parks, the parks should develop a tracking mechanism to monitor collecting. This may be as simple as having visitors complete a form or questionnaire.

9. Manage Mineral Exploration and Development

Managers need to distinguish geologic research that is beneficial to the unit and the NPS from mineral assessment and exploration, including such operations as mining, oil and gas exploration and development, and quarrying mineral materials such as sand and gravel. For guidance, see the Minerals Management Handbook.

Specific Geologic Resources

Geologic resources are numerous and diverse, but the program elements of geologic resources management, as described above, can generally apply to them all. Further guidance for managing caves and karst, soils, paleontological resources, and marine and lake shoreline areas, and for restoring disturbed lands, is provided in the sections with the same titles in this Reference Manual. Detailed guidance for managing fluvial features and processes, geothermal resources, glaciers, volcanoes, arid lands, and Quaternary landforms and paleoecological deposits is provided below.

Fluvial Features and Processes Fluvial (river) processes have created some of the most spectacular geologic features of the National Park System. Streams are part of systems that move sediment, water, and woody debris down slope. These systems operate at a watershed scale, where processes of erosion and deposition create local habitat features such as canyons, arroyos, floodplains, woody debris accumulations, terraces, gravel bars, islands, riffles, and pools.

The primary goals of managing fluvial systems are to:

1. perpetuate large-scale processes and landscape features,
2. perpetuate local habitat features dependent on fluvial processes, and
3. protect life and property from flooding and other hazards.

To perpetuate processes and landscape features, natural watershed processes should be protected. These processes include mass movements and disturbances to vegetation (from fire, insects, and meteorologic events), and naturally regulate the delivery of sediment, wood, and water to streams. Disturbance events should be allowed to proceed unimpeded when possible.

Accomplishment of the second goal, perpetuation of local habitat features, requires protecting those features from roads, facilities, or land uses that interfere with or are threatened by natural fluvial processes.The most common motivation for interfering with fluvial processes is the protection of developments from those processes. When conflicts between infrastructure and stream processes occur, managers should first consider relocating facilities rather than manipulating streams. When stream manipulation is unavoidable, managers should use materials that resemble those that occur naturally at that site. For example, parks should avoid using rip-rap, gabions, groins, and other large obtrusive structures made from materials that are not found in natural settings, such as concrete.

Parks should also use techniques that accommodate natural processes to the greatest extent possible, such as bioengineering, constructed woody debris accumulations, and rock barbs, and when possible remove and restore those areas where old designs and structures use techniques such as rip-rap and features that impede floodplain processes. Bioengineering is the incorporation of riparian plants, typically willow and dogwood, into erosion control systems. Depending on site conditions, plants can be used alone or in combination with erosion control fabrics and more traditional stabilization structures such as rock walls and log cribbing. Bioengineering techniques both restore riparian habitat and increase in strength over time. Rock barbs are triangular structures composed of large rocks that are oriented upstream along eroding banks. Unlike bank hardening (rip-rap) structures, rock barbs re-direct the force of a stream away from an eroding bank and dissipate energy. Rock barbs use less rock than rip-rap, are compatible with recreational use, and create pool habitat.

In the case of bridges, NPS managers should ensure that Federal Highway Administration designs are adequate to move sediment and woody debris, as well as water, through bridge openings. The park should also work to ensure that the bridge design minimizes impedance of floodplain processes. The bridge length should approximate the natural width of the channel as measured in a reach unaffected by the bridge. This will allow for the movement of water, wood, and sediment beneath the bridge, and prevent backwater flooding and erosion to bridge piers and approach roadways. Large mid-stream gravel bars immediately upstream or downstream of the bridge are often an indication that the bridge opening is too narrow.

Parks should inventory and monitor the health of fluvial systems, including activities and land uses within the watershed and their cumulative impacts, and should include management of these systems in general management plans and other planning and compliance documents.

Managers should collect information on flooding and other events along streams and in watersheds. Help with erosion control problems and bridge replacements can be obtained by technical assistance requests to the Natural Resource Program Center’s Water Resources Division. Information on watershed processes such as flooding can be obtained from the nearest USGS Water Resources Division office or from their Internet site www.usgs.gov. Additional information can also be obtained from the Bureau of Reclamation, the Corps of Engineers, and the Natural Resources Conservation Service. Executive Orders 11988 and 11989 on wetland and floodplain management give legal direction for the protection of wetlands and floodplains and executive direction to remove facilities from floodplains.

The third goal of NPS fluvial system management, protection of life and property, may be accomplished by following the suggestions of DO77-2 Floodplain Management and the NPS Floodplain Management Procedural Manual.

For more information about fluvial systems, see Freshwater Resources Management in this Reference Manual.

Geothermal Resources

Geothermal resources include features such as geysers, fumeroles, hot springs, hot pools, soda springs, mud pots, and travertine terrace deposits. Geothermal features can also take the form of less obvious thermal seeps, brine marshes, and in-stream springs that can create rare habitats for delicate, temperature-dependent species. These thermal features are surface expressions of an extensive underground hot water convection system, normally driven by the heat of magma chambers and geologic hotspots.

Thermal features throughout the National Park System need to be recognized, understood, and protected from visitor impacts as well as from geothermal development both inside and outside the park boundaries. To accomplish these tasks, the NPS should:

1. know the location of thermal features within each park unit,
2. understand the nature of these systems in enough detail to know what changes or impacts the thermal feature and its associated habitat can tolerate and which will cause damage, and
3. apply this knowledge to implement monitoring and/or modify park planning to ensure that these features and habitats are not damaged.

1. Knowing the location of thermal features within each park unit.

As required by the Geothermal Steam Act as amended, 30 U.S.C. §§ 1001-1028, the NPS maintains a list of the significant thermal features that are in the following 16 park units:

• Mount Rainier National Park
• Yellowstone National Park
• John D. Rockefeller, Jr., Memorial Parkway
• Bering Land Bridge National Preserve
• Gates of the Arctic National Park and Preserve
• Katmai National Park
• Aniakchak National Monument and Preserve
• Wrangell-St. Elias National Park and Preserve
• Lake Clark National Park and Preserve
• Hot Springs National Park
• Lassen Volcanic National Park
• Hawaii Volcanoes National Park
• Haleakala National Park
• Crater Lake National Park
• Big Bend National Park
• Lake Mead National Recreation Area

The current list of the significant thermal features in these parks is contained in the Federal Register (52 F.R. 28790 (Aug. 3, 1987)). The NPS may, after public notice and comment, add more significant thermal features in these or other park units to the list. "Significance" is based on the features’ (1) size, extent, and uniqueness; (2) scientific and geologic significance; (3) extent to which such features remain in a natural, undisturbed condition; and (4) significance to the authorized purposes for which the park unit was established.

The NPS’s list of significant geothermal features is not exhaustive. It is likely that many significant thermal features exist that are not presently recognized, and that many parks contain thermal features that are not "significant" as defined by the Act but that nonetheless are important. Assistance in acquiring this information can be obtained through technical assistance requests to the NPS Geologic Resources Division, the NPS Water Resources Division, the USGS, or local universities. The location of thermal features can often be displayed on a map and database that can be incorporated into the park’s GIS.

2. Understanding the nature of the geothermal systems.

Each geothermal system is unique. Geothermal systems are generally the result of unusual and complex hydrogeologic conditions and geologic structures, such as fault zones and intense folding or deformation of geologic formations. Geothermal systems have long attracted the attention of geologists because they are such unique and interesting geologic features. Previous studies usually have identified the geologic conditions that created many of the geothermal systems in parks. The hydrology of geothermal systems is probably less well known and more difficult to document. However, hydrologic systems are more fragile and susceptible to disruption from development outside the park. Complex hydrogeologic conditions associated with geothermal systems may make cause-and-effect studies much more difficult to verify.

Drilling may be appropriate to help determine the geologic and hydrologic conditions that result in the presence of unique geothermal systems but extensive drilling can be inconsistent with park protection. Other methods of data collection should be given full consideration before a decision is made to drill. Geochemical analyses of geothermal waters are sometimes useful in determining the age of the water (the amount of time since the water entered the groundwater system by infiltration from the surface). Geochemistry can also help determine the flow paths from recharge to discharge areas, the type of rock formations the water has been in contact with, and the relative amount of time the water has been in contact with each formation. Surface geophysical methods can be helpful in defining the geologic structure associated with geothermal systems. Non-intrusive methods, such as gravity surveys, conductivity or resistivity surveys, thermography, and shallow seismic reflection and refraction will provide much useful information about near-surface geologic features associated with geothermal systems.

A long-term monitoring program is the only way to document natural changes in thermal features and to accurately determine changes due to development. The NPS is required by the Geothermal Steam Act to maintain a monitoring program for significant NPS thermal features, including a research program in cooperation with the USGS. Since each geothermal system is unique, inventory and monitoring programs should be individually tailored for each system.

Assistance in understanding geothermal systems and developing inventory and monitoring programs can be obtained through the NPS Geologic Resources Division, NPS Water Resources Division, USGS, state geological surveys, or local colleges and universities.

3. Applying the knowledge to management

Monitoring and protection are the key elements in managing geothermal resources.

Visitor protection

Because in some instances the temperatures associated with the resources are extremely high, the NPS should work to protect the public from geysers, hot springs, hot pools, and fumaroles. These features may also emit poisonous gases that could be dangerous to visitors.

Resource protection

Geothermal resources are fragile, and they must be protected from overuse and abuse. It may be necessary in some situations to fence, patrol, or otherwise keep these resources safe from human interaction.

The park should also keep track of any proposed changes or developments outside the park, such as water well drilling, oil and gas well drilling, geothermal development, and waste disposal that might affect the park’s geothermal resources or groundwater system. Both the recreational and commercial use of geothermal sites can adversely affect these resources. In many park units, such as Yellowstone and Crater Lake National Parks, geothermal features inside the parks may be connected to hot water systems outside the boundaries. Therefore, one of the most significant impacts of geothermal development is the potential depletion or extinction of a park’s natural thermal features. Other impacts include:

• land subsidence,
• an increase in seismic activity,
• the release of noxious gases,
• noise from drilling and power plant construction,
• effects on the park’s groundwater system, and
• the release of polluted water and brines.

The Geothermal Steam Act requires the Secretary of the Interior to determine on the basis of scientific evidence whether geothermal exploration or development is reasonably likely to result in adverse effects on significant NPS thermal features. If so, the lease or drilling permits must include stipulations for protecting the features. If the geothermal exploration or development is reasonably likely to result in significant adverse effects on significant NPS thermal features, the Act requires the Secretary to deny the application.

NPS Management Policies (2001) contain the following direction for managing geothermal resources.

4.8.2.3 Geothermal and Hydrothermal Resources

Thermal resources within units of the national park system will be protected, preserved, and managed as a critical component of the units’ natural resource systems, and for public education, interpretation, and scientific research. Thermal resources, also known as geothermal or hydrothermal systems, are comprised of a subsurface heat source, heat conduit rock formations, and air and/ or water that circulates through the formations and may discharge at the surface, creating features such as geysers, hot springs, mudpots, fumaroles, unique/ rare mineral precipitates and formations, and hydrophilic biotic communities.

Superintendents will strive to maintain the natural integrity of thermal systems, including the movement of air and/ or water through the heated rock, cold water recharge, the proximity of the hot and warm water to the heat source, and the hydrostatic pressure and elevated temperature.

Superintendents will work to prevent impacts caused by the development of thermal resources. Such impacts include the loss of surface thermal features; land subsidence; an increase in seismic activity; the release of noxious gases; noise and surface disturbance from drilling or power plant construction; and the release of polluted water or brines. Because thermal systems may extend well beyond park boundaries, the NPS will work closely with federal, state, and tribal agencies to delineate the full extent of thermal resources, and protect those that occur within parks. In protecting park thermal resources, superintendents should consider authorities available under the Geothermal Steam Act of 1970, as amended; state water rights; and mineral leasing laws.

As required by the Geothermal Steam Act, the NPS will maintain a list of significant thermal features within park units. The criteria and procedures for designating significant thermal resources within parks are specified within the Geothermal Steam Act Amendments of 1988. In cooperation with the U. S. Geological Survey, the NPS will conduct a monitoring program for the designated significant thermal features.

Glaciers and Glacial Features and Processes

Many NPS areas have glaciers and deposits from past glaciers. The primary concerns for managing glaciers and glacial processes and features are ecosystem integrity, visitor and employee safety, and visitor impacts. Inventory, monitoring, and research of glacier features and processes form the basis for glacier management and interpretation. Resource management Glaciers and their deposits are valuable resources at many NPS areas. For example, glaciers supply vast quantities of meltwater to lakes and streams. Glacial meltwater is characteristically colder and more turbid than snow meltwater. Further, annual peaks in glacial runoff occur at the hottest, driest time of year in the American west, helping buffer streams from extreme low flows. Glaciers are also valuable as indicators of regional climate change. For these and other reasons, NPS areas should actively manage the glacier resource using information gained through inventory, monitoring, and research programs. Inventories of glaciers should be conducted approximately every 10 years. Inventories should include several characteristics of each identifiable glacier such as glacier form, length, surface area, top elevation, bottom elevation, and margin activity. Many of these attributes can be measured directly from maps or air photos. Glacier monitoring should focus on two areas: marginal activity and surface mass balance. Changes in the marginal position of glaciers can identify long-term trends in glacial activity and the presence of hazards. This information can also be used to interpret glacial change and to plan interpretive displays. Changes in glacier margins can be monitored by field surveys from fixed points or from air photos. A well-balanced monitoring program would include both methods. Changes in the marginal position, however, are not an accurate estimation of glacier activity on time scales of less than a few decades. Therefore, surface mass balance monitoring should be conducted to determine short-term variations in glaciers. In NPS areas with many glaciers, it will be fiscally impossible to monitor the surface mass balance of all glaciers. In these areas, index glaciers that represent a range in glacial conditions such as elevation, aspect, and geographic position should be selected for monitoring. Ongoing surface mass balance monitoring programs at North Cascades National Park and Denali National Park can provide assistance in developing new monitoring projects.

Visitor and employee safety and impacts

Glaciers can be hazardous to people. Large chunks of snow, ice, and rock commonly fall off of glaciers, particularly at their margins. Some glaciers are also known to produce catastrophic floods known as "jokulhaups" or "outburst floods." Glacial deposits are also hazardous because they are typically unstable. Ice cores, complex stratigraphy, a lack of vegetation cover, over-steepened slopes (caused by glacial erosion and glacier retreat, which removes lateral support to moraine deposits), and other factors contribute to the instability of glacial deposits .Interpretation and facility placement near the margins of glaciers, unstable glacial deposits, or glacial meltwater streams should consider and explain these hazards. Further, since glaciers move, facility locations should be carefully chosen. Some glaciers are prone to rapid movements know as "surges." Glaciers known to surge present a special hazard to people and facilities. Travel across glaciers presents additional hazards for people, and human waste disposal presents concerns for resource managers. Crevasses, moulins, and other surface features of glaciers present considerable hazards. (Moulins are meltwater drainage openings on the surface of glaciers that carry water from the surface to meltwater streams at the bed of the glacier. The largest moulins form in stagnating ice masses. Crevasses can range up to 150' deep, while moulins can reach several hundred feet in depth from the surface to the bed of stagnant glaciers.) Steep slopes on glaciers are a sliding hazard. All of these hazards make it important for people traveling across glaciers to have specialized training and equipment.

Human waste should generally not be disposed of on glaciers since glaciers are directly connected to surface streams. In designated camps on glaciers and snowfields it may be necessary to have composting toilets or require users to pack-out waste. Placement of any facilities on glaciers must take into account the instability of the glacier surface due to rapid summer surface melt rates. (See Backcountry Recreation Management in this Reference Manual for further discussion of human waste management.)

Volcanoes

The NPS is responsible for managing a wide range of volcanic resources, from active volcanoes to Precambrian volcanic deposits. Different types of volcanic deposits and volcanic systems require different management strategies. Although Active and Holocene volcanic resources require the most active and proactive management strategies because of the potential for eruption, yet other volcanoes may also present special management concerns. The primary goals for managing National Park System volcanic resources are to assess volcanic hazards; reduce exposure of life and property to volcanic hazards; maintain the integrity of volcanic landforms, features, and the natural systems that built them; and protect volcanic resources from visitor impacts. Volcanic hazards Volcanoes can present a variety of hazards to life, health, and property. Active volcanoes are the most dangerous to people, and park managers should strive tomust respond to changing eruption conditions. Most volcanic hazards are triggered directly by an eruption and occur near erupting volcanoes. Large explosive eruptions may endanger people and property hundreds of miles away. Specifically, potential volcanic hazards include eruption columns and clouds, poisonous gasses and acid rain, pyroclastic flows, ash fall, lava flows, landslides, debris avalanches, lahars (volcanic mud flows), floods, and geothermal features. Geothermal areas may be arehazardous because of high pool temperatures or acidity and because thin siliceous crusts over pools may break if stepped upon. Ash clouds are extremely hazardous to aircraft. Gas emissions may be an invisible threat. Many poisonous volcanic gasses, including carbon dioxide, are heavier than air and may accumulate in basins or depressions. Conventionally, vulcanologists classify any volcano that has erupted during the last 10,000 years as potentially active. At least 16 park areas contain active or potentially active volcanoes, and several volcanoes in park sites have seen historical eruptions. The United States GS has assessed volcanic hazards in a number of park areas, and park managers in those areas should work closely with USGS scientists and the Federal Emergency Management Agency to assess and mitigate volcanic hazards and to have emergency preparedness plans in place. The USGS also maintains volcano observatories in Hawaii, the Cascades, and Alaska. Scientists from these observatories actively monitor several volcanoes within the National Park System for signs of impending eruption. The Hawaii Volcano Observatory is located in Hawaii Volcanoes National Park.Even inactive volcanoes pose potential hazards. Young lava flow surfaces may have sharp and unstable surfaces. Lava tubes may collapse. Floods, landslides, and lahars (mud flows) may occur. Volcanoes, even inactive ones, are susceptible to landslides because circulating hydrothermal fluids may have altered and weakened volcanic rock. Landslides may also be brought on by heavy rainfall, melting of snow or ice, or by earthquakes. Lahars , which are volcanic mud flows, have historically been one of the deadliest volcanic hazards. To reduce risk to life and property, park facilities should not be placed in potential lahar pathways. Resource management Resource management activities on active or potentially active volcanic systems should focus on minimizing life and property exposure to volcanic hazards and monitoring for future eruptions. Older volcanic landforms, mountains, or features provide fewer unique management challenges, and usually may be managed like similar landforms not of volcanic origin. However, managers should be aware that volcanic rock may have been altered and weakened by hydrothermal fluids, and that some volcanic deposits, including ash fall, pyroclastic tuff, and lahar deposits may be unstable on steep slopes or at risk for slope failure. Park facilities, including roads, trails, and structures, should not be placed on or below unstable slopes. Where facilities already exist, park managers must take steps to mitigate impacts on the resource and to minimize threats of damage to life and property. Because mineral deposits are common in some volcanic terrains, park staff should be aware that abandoned mineral land sites may be located in these areas. Certain volcanic rock types, including obsidian, pumice, cinders, and some volcanic bombs (large cinders with rounded, spindle, or ribbon shapes) are at particular risk of collection by visitors. Park managers in areas that contain these rock types should maintain public education programs to minimize this resource threat. Research Volcanic resources in national park areas are of special interest to researchers. Each volcanic eruption adds to our understanding of volcanic systems and may help scientists predict future eruptions. Monitoring of potentially active volcanoes can also help park managers minimize risk exposure for life and property. The range of volcanic resources in park areas include all major types of volcanic landforms, systems, deposits, and rock types that may be the focus of volcanology, geomorphology, petrology, and paleomagmatism studies. Lava tubes, with their interests to speleologists, are not uncommon in areas with basaltic lava flows. Active and inactive cinder cones are present in several park units.Ash beds are particularly important to a number of researchers, including paleontologists, and are found in a large number of national park areas. Absolute age determinations performed on ash beds found in sedimentary sequences have bracketed ages for a number of important fossils. Interpretation and visitor safety

Volcanic resources, especially active or young volcanoes, are compelling to many park visitors. Interpretation of volcanic resources should highlight principles not only of volcanism, but also of the dynamic earth and geo-ecology. NPS National Park Service interpreters should partner with USGS and other researchers to provide data on volcano monitoring where appropriate, and to educate the public on dangers of volcanic hazards and how to avoid them.

Arid Land Features and Processes

Arid landscapes contain spectacular features created by processes of wind and water erosion and deposition. These include dunes, arches, natural bridges, hoodoos, badlands, and canyons. Significant features of arid lands also include playas with their unique salt deposits and large ancient colluvial fans. Arid land features and rock alteration is affected by wind and temperature changes on a daily basis and over a very long time period. Precipitation is limited and usually comes in short intense events. The sudden increase in precipitation in sparsely vegetated areas leads to flash floods that can significantly alter the terrain and threaten park infrastructure and visitors. Desert crusts, pavements, polish, and varnish are typical aspects of the land surface, which can be damaged by even minor pedestrian traffic. In some cases, formation of these features can take extremely long periods of time, while in other cases they can be created and destroyed rapidly. In all cases, these features are typically very fragile.

The primary goal in managing these resources is to perpetuate the processes that created them. Perpetuating the processes will allow for renewal of features and will ensure their ultimate survival. Research programs should be developed that identify the nature, timing, and magnitude of the processes. In the case of relict features, researching and perpetuating the processes may be impossible because they may no longer be active. In other cases, processes may operate intermittently, such as during ice ages or other cyclic climatic events.

Secondary goals are to inventory features, monitor their condition, and take management action if necessary to preserve them. Protection of these resources may include interpretation, bans on construction activities, restrictions on public access, and closures. In some cases, features can be restored through the reestablishment of processes truncated by human activity. For example, controlled releases from dams mimic floods and reconstruct fluvial features such as gravel bars in the Grand Canyon.

Assistance in managing arid features and processes can be accomplished though a number of independent or related actions. These include technical assistance requests to the Geologic Resources Division, technical assistance through the Geologists in the Parks Program, and arrangements with the USGS or local colleges and universities.

Quaternary Landforms and Paleoecological Deposits

Virtually no NPS unit has escaped the influence of the ice ages during the most recent period of earth history known to geologists as the Quaternary Period. While some NPS areas were buried beneath glacial ice more than 1.5 miles thick, other areas far from the direct influence of glaciers were subject to change as well. Dramatic environmental changes that occurred throughout North America included colossal flooding, mass extinction of animal species, and reconfiguration of vegetation communities. Many of these same threats face NPS areas today. Human-induced climatic change, pollution, development, and other factors are causing environmental change that approaches the scale of the ice ages. Understanding past change provides the key for predicting and managing inevitable future environmental changes. Most NPS areas contain records of the magnitude, timing, and duration of events dating from the Quaternary Period that can help us understand past change. These records are held in the ancient deposits throughout the National Park System. River terraces, lake-bed deposits, glacial moraines, and landslide deposits are examples of significant Quaternary resources. Moraines are particularly important features that identify the past position of glaciers. Thus, moraines can provide information on past climate. Information on past change in physical systems and plant and animal communities can be effectively extracted from these deposits. The fine-grained deposits of former lake beds contain organic material for radiocarbon dating, animal fossils, plant pollen, and plant macrofossils, ideal for reconstructing past environmental conditions. In some cases, Quaternary deposits may be concealed beneath soil and vegetation, while in road cuts and river cut banks, Quaternary deposits are exposed for interpretation and scientific investigation. In addition to their paleoecological value, Quaternary landforms and deposits are valuable for several other reasons. First, landforms can be important as indicators of the age and magnitude of geological hazards. Second, glacial and Quaternary deposits are also sources of groundwater, parent materials for soils, and foundations for buildings. Third, archaeological resources are inextricably linked with Quaternary landforms and deposits.The primary objectives for managing Quaternary deposits and landforms are to protect them from disturbance or to obtain information from them before they are permanently concealed or destroyed. Areas prone to rapid rates of erosion, such as along reservoir shorelines or areas due to be disturbed by construction activities, are particularly important to manage. In cases where deposits are threatened by erosion caused by natural processes, it will be necessary to extract information before the deposit is destroyed. This approach will negate the possibility of a conflict between resource protection and perpetuation of a natural process.

NPS managers should initially develop inventories of Quaternary deposits. Landform maps, locations of road cuts and stream exposures, and other information on Quaternary deposits should be entered into the park's GIS. This information can be obtained from state geology offices or through research programs, arrangements with the USGS or local colleges and universities, reviews of literature, technical assistance requests to the Geologic Resources Division, and/or technical assistance through the Geologists in the Parks Program. (Also see Paleontological Resources Management in this Reference Manual).

Geologic Resources Management Table of Contents | RM#77 Table of Contents