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Rules for success in environmental negotiations

Scientists at the Mid-Continent Ecological Science Center of the National Biological Service conducted a series of case studies of Federal Energy Regulatory Commission license consultations. The goal of these studies was to test hypotheses about factors that contribute to success in interagency negotiations. Based on their analysis of six case studies, the researchers constructed a list of ten "rules for success." Examples include: Analyze the incentives of each party to negotiate, paying special attention to parties who gain by not negotiating; Clarify the technical issues so that all agree and they coincide with resource management objectives; and Make sure the final agreement is feasible from both a physical and a policy perspective so that it can actually be implemented. These rules can be used to plan for negotiations and to diagnose ongoing negotiations.

Conference Paper↗

Gulf Coast Ecosystem Restoration Task Force---Gulf of Mexico Ecosystem Science Assessment and Needs

The Gulf Coast Ecosystem Restoration Task Force (GCERTF) was established by Executive Order 13554 as a result of recommendations from “America’s Gulf Coast: A Long-term Recovery Plan after the Deepwater Horizon Oil Spill” by Secretary of the Navy Ray Mabus (Mabus Report). The GCERTF consists of members from 11 Federal agencies and representatives from each State bordering the Gulf of Mexico. The GCERTF was charged to develop a holistic, long-term, science-based Regional Ecosystem Restoration Strategy for the Gulf of Mexico. Federal and State agencies staffed the GCERTF with experts in fields such as policy, budgeting, and science to help develop the Strategy. The Strategy was built on existing authorities and resources and represents enhanced collaboration and a recognition of the shared responsibility among Federal and State governments to restore the Gulf Coast ecosystem. In this time of severe fiscal constraints, Task Force member agencies and States are committed to establishing shared priorities and working together to achieve them. As part of this effort, three staffers, one National Oceanic and Atmospheric Administration (NOAA) scientist and two U.S. Geological Survey (USGS) scientists, created and led a Science Coordination Team (SCT) to guide scientific input into the development of the Gulf of Mexico Regional Ecosystem Restoration Strategy. The SCT leads from the GCERTF coordinated more than 70 scientists from the Federal and State Task Force member agencies to participate in development of a restoration-oriented science document focused on the entire Gulf of Mexico, from inland watersheds to the deep blue waters. The SCT leads and scientists were organized into six different working groups based on expanded goals from the Mabus Report: Coastal habitats are healthy and resilient. Living coastal and marine resources are healthy, diverse, and sustainable. Coastal communities are adaptive and resilient. Storm buffers are sustainable. Inland habitats and watersheds are managed to help support healthy and sustainable Gulf of Mexico ecosystems. Offshore environments are healthy and well managed Each working group was charged with defining their specific goal, describing the current conditions related to that goal (for example, the status of coastal habitats in the Gulf of Mexico), providing highlevel activities needed to further define and achieve the goal, with associated outcome-based performance indicators, and identifying the scientific gaps in understanding to accomplish the goal and implement the recommended activities. The overall scientific assessment reveals that the Gulf of Mexico ecosystem continues to suffer from extensive degradation, and action is necessary to develop a healthy, resilient, and sustainable Gulf of Mexico ecosystem. The six groups also were tasked with outlining the necessary monitoring, modeling, and research needs to aid in achieving the goals. Recognizing that (1) the scientific needs (monitoring, modeling, and research) overlap among many of the goals, and (2) an overarching scientific framework could be developed to implement the necessary science in support of the Strategy, a seventh group was created with several members from each of the original six working groups. This seventh group compiled all of the cross-cutting monitoring, modeling, and research needs previously identified by the individual groups. These scientific requirements are found in Chapter 5 of this document. The seventh group also has developed a Science Plan, outlined in Chapter 6. The Science Plan provides the basic science infrastructure to support the overall Gulf restoration program and Strategy. The Science Plan allows for the development of an iterative and flexible approach to adaptive management and decision-making related to restoration projects based on sound science that includes monitoring, modeling, and research. Taken in its entirety, this document helps to articulate the current state of the system and the critical science needs to support effective restoration of the Gulf of Mexico resources that have been trending towards decline for decades.

Report↗

Application of landscape models to alternative futures analyses

Scientists and environmental managers alike are concerned about broadscale changes in land use and landscape pattern and their cumulative impact on environmental and economic end points, such as water quality and quantity, species habitat, productivity, erosion potential, recreational value, and overall ecological health (Rapport et al., 1998). They also are interested in predicting short-and long-term future impacts on ecological goods and services based on current land management policies and decisions (Steinitz, 1996). Because we have the means to adjust land management policies, it is worthwhile to develop approaches that can predict the consequences (alternative futures) of different land management policies for different environmental end points. This type of analysis can, for example, allow decision makers in resource conservation and restoration programs to estimate how they can get the most ecological benefit for the least cost

Delaware, Maryland, New York, Pennsylvania, Virgin↗

Adaptive management: The U.S. Department of the Interior technical guide

The purpose of this technical guide is to present an operational definition of adaptive management, identify the conditions in which adaptive management should be considered, and describe the process of using adaptive management for managing natural resources. The guide is not an exhaustive discussion of adaptive management, nor does it include detailed specifications for individual projects. However, it should aid U.S. Department of the Interior (DOI) managers and practitioners in determining when and how to apply adaptive management. Adaptive management is framed within the context of structured decision making, with an emphasis on uncertainty about resource responses to management actions and the value of reducing that uncertainty to improve management. Though learning plays a key role in adaptive management, it is seen here as a means to an end, namely good management, and not an end in itself. The operational definition used in the guide is adopted from the National Research Council, which characterizes adaptive management as an iterative learning process producing improved understanding and improved management over time: Adaptive management [is a decision process that] promotes flexible decision making that can be adjusted in the face of uncertainties as outcomes from management actions and other events become better understood. Careful monitoring of these outcomes both advances scientific understanding and helps adjust policies or operations as part of an iterative learning process. Adaptive management also recognizes the importance of natural variability in contributing to ecological resilience and productivity. It is not a ‘trial and error’ process, but rather emphasizes learning while doing. Adaptive management does not represent an end in itself, but rather a means to more effective decisions and enhanced benefits. Its true measure is in how well it helps meet environmental, social, and economic goals, increases scientific knowledge, and reduces tensions among stakeholders. Adaptive management as defined here involves ongoing, real-time learning and knowledge creation, both in a substantive sense and in terms of the adaptive process itself. It is described in what follows in a series of 9 steps, as summarized in section 4.1, involving stakeholder involvement, management objectives, management alternatives, predictive models, monitoring plans, decision making, monitoring responses to management, assessment, and adjustment to management actions. An adaptive approach actively engages stakeholders in all phases of a project over its timeframe, facilitating mutual learning and reinforcing the commitment to learning-based management. Adaptive management in DOI is implemented within a legal context that includes statutory authorities such as the National Environmental Policy Act (NEPA), the Endangered Species Act, and the Federal Advisory Committee Act. For many important problems now facing the resource management community, adaptive management holds great promise in reducing the uncertainties that limit the effective management of natural resource systems. For many conservation and management problems, utilizing management itself in an experimental context may be the only feasible way to gain the system understanding needed to improve management. Though it is commonly thought that an adaptive approach can produce results quickly at low cost, the opposite is more likely to be true. An initial investment of time and effort will increase the likelihood of better decision making and resource stewardship in the future, but patience, flexibility, and support are needed over the life of an adaptive management project. For these reasons it is important to carefully consider the potential use of an adaptive approach, and to engage in careful planning and evaluation when adaptive management is used.

Report↗

Best practices for incorporating climate change science into Department of the Interior analyses, consultations, and decision making

The purpose of this document is to provide technical guidance, practical application examples, and resource lists for those who conduct, manage, and/or interpret technical workflows within the Department of the Interior. This document is intended to support implementation of Department of the Interior policy 526 DM 1 and establish best practices for using climate change science to inform analysis, consultation, and decision making. The Earth’s climate is an interconnected system that distributes energy, heat, and water around the planet. Due to human-driven increases in long-lived greenhouse gases, the Earth’s climate is now changing. For Departmental decision-making purposes, assuming a static, unchanging baseline climate is no longer consistent with current knowledge about the climate system. There are uncertainties about future climate and how resources or assets (RoAs) will respond to new conditions. To depict the possibilities, the global climate science community develops scenarios and models to explore how future climate may respond to socioeconomic and technological development in the world. Principles for informing policy development, planning and decisions, and regulatory processes using climate change science must: 1) consider the effects of future climate change, 2) characterize the risks, and 3) characterize the uncertainties. Best practices include: Use multiple scenarios to assess risks from a range of plausible societal pathways. When constraints prevent the use of multiple scenarios or if decision makers are risk averse, ensure that the chosen scenario considers higher risk outcomes. This is particularly important for large investments or irreversible decisions and reduces the chances of overconfident decision making. Use multiple climate models within each scenario to account for the range of outcomes due to model uncertainty. Do not rely solely on a single model or an ensemble average. Use relevant climate data . Use a time-period for model projections of the future climate change consistent with the relevant timeframe of the policy, action, or decision being considered. Historical observations are useful for understanding past conditions and climate trends for the next several years, but not beyond the next decade. Consult with climate data and modeling experts to assess which data and model resources are most appropriate for any given application. Clearly describe key analysis uncertainties (including with any climate observations, models, and scenarios used), and how they were addressed in the analysis and/or decision process. This ensures transparency and learning among analysts and decision makers.

Report↗

NOGA Online: a USGS resource for energy GIS data and services

The PowerPoint presentation in this report was given at the BLM Resource Management Tools Conference in Phoenix, Arizona, April, 2003. Some diagrams that appeared in the original presentation have been updated in this report. It informs that the U.S. Geological Survey (USGS) Central Energy Resources Team (CERT) in Denver, Colorado, is providing National Oil and Gas Assessment (NOGA) results online at http://energy.cr.usgs.gov/oilgas/noga/. Available at this site are recently completed assessments of the potential for undiscovered oil and natural gas resources of five priority provinces (Montana Thrust Belt, Powder River Basin, San Juan Basin, Southwestern Wyoming, Uinta-Piceance) to meet the requirements of the Energy Policy and Conservation Act of 2000 (EPCA 2000). High demand for current assessment results and for the entirely digital, 1995 NOGA results for other provinces, prompted CERT to develop an internet map application using ArcIMS to deliver geologic data to the public. CERT continues to work on assessing oil and natural gas resources of priority basins in the United States; assessment results and GIS layers are made available at this site on an ongoing basis.

Open-File Report↗

Assessing the quality of the nation's water resources

This issue of IMPACT highlights findings from the first decade of studies (1991 to 2001) by the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS). The articles also discuss the Program’s approaches and models designed to help understand and estimate the fate and transport of contaminants in different geographic areas and environmental settings and over different time frames. NAWQA was established by Congress in 1991 with a goal of developing long-term, consistent, and comparable science-based information on nationwide water-quality conditions. This information is used to support sound management and policy decisions by decision makers at all levels – local, state, and national – who, every day, face complex regulations and management issues related to water resources.

Water Resources Impact↗

Don’t move a mussel: The role of key environmental drivers and management scale in assessing spatial variation in dreissenid spread risk in the Missouri River Basin

The spread of non-native freshwater mussels in North America is a growing threat that has already resulted in substantial ecological and economic damage to infested areas. A primary vector by which invasive mussels spread is watercraft that are transported over land from an infested waterbody to an uninfested waterbody. Management efforts such as watercraft inspection and detection programs that attempt to intercept infected watercraft can help limit this type of spread, but optimizing the effectiveness of these programs under limited resources is complicated. Studies have looked at developing watercraft inspection and decontamination program strategies that focus on policy-specific objectives such as maximizing the number of infested watercraft interceptions. However, there is limited work that has considered the heterogeneous impact of protection efforts across different regions and waterbodies. Knowledge about this heterogeneity can highlight regions that would benefit the most from protection as well as regions that would require less effort to protect, e.g., areas with naturally unsuitable water quality for dreissenids. To this end, we construct a composite relative risk index (CRR) for watersheds within the Missouri River Basin, a region in the United States on the front line of dreissenid spread. The CRR uses a model that mirrors an expected value model but uses relative indexing as a proxy for the model components. The CRR incorporates a wide array of data sets to account for the direct and indirect damages from a potential infestation along with the risk of an infestation occurring. Our results suggest that the relative priority of a specific watershed—measured through CRR—can depend on whether we consider the entire Missouri River Basin or just the watersheds in the same state. This also indicates substantial state-level heterogeneity in the CRR. Another contribution is that the CRR index includes user-specified weights for certain parameters so that a user can adjust the relative importance of various factors to match their specific context. An accompanying web tool allows users to view the CRR results and adjust multiple parameters to see the resulting impacts on the CCR for watersheds in the Missouri River Basin.

Missouri River Basin↗

Isohaline position as a habitat indicator for estuarine populations

Populations of native and introduced aquatic organisms in the San Francisco Bay/Sacramento-San Joaquin Delta Estuary ("Bay/Delta") have undergone significant declines over the past two decades. Decreased river inflow due to drought and increased freshwater diversion have contributed to the decline of at least some populations. Effective management of the estuary's biological resources requires a sensitive indicator of the response to freshwater inflow that has ecological significance, can be measured accurately and easily, and could be used as a "policy" variable to set standards for managing freshwater inflow. Positioning of the 2% (grams of salt per kilogram of seawater) bottom salinity value along the axis of the estuary was examined for this purpose. The 2% bottom salinity position (denoted by X 2 ) has simple and significant statistical relationships with annual measures of many estuarine resources, including the supply of phytoplankton and phytoplankton-derived detritus from local production and river loading; benthic macroinvertebrates (molluscs); mysids and shrimp; larval fish survival; and the abundance of planktivorous, piscivorous, and bottom-foraging fish. The actual mechanisms are understood for only a few of these populations. X 2 also satisfies other recognized requirements for a habitat indicator and probably can be measured with greater accuracy and precision than alternative habitat indicators such as net freshwater inflow into the estuary. The 2% value may not have special ecological significance for other estuaries (in the Bay/Delta, it marks the locations of an estuarine turbidity maximum and peaks in the abundance of several estuarine organisms), but the concept of using near-bottom isohaline position as a habitat indicator should be widely applicable. Although X 2 is a sensitive index of the estuarine community's response to net freshwater inflow, other hydraulic features of the estuary also determine population abundances and resource levels. In particular, diversion of water for export from or consumption within the estuary can have a direct effect on population abundance independent of its effect on X 2 . The need to consider diversion, in addition to X 2 , for managing certain estuarine resources is illustrated using striped bass survival as an example. The striped bass survival data were also used to illustrate a related important point: incorporating additional explanatory variables may decrease the prediction error for a population or process, but it can increase the uncertainty in parameter estimates and management strategies based on these estimates. Even in cases where the uncertainty is currently too large to guide management decisions, an uncertainty analysis can identify the most practical direction for future data acquisition.

California↗

Government investment in mineral resource information on leasable public lands: The case of strippable coal

A scheme is presented to aid the government in estimating the net benefits, in terms of itsrecovery of expected rents, of performing various levels of exploration of mineral tracts prior to leasing and making such information available to potential bidders. Conditions are identified where the government will profit by investment in geologic data that are collected and provided to potential bidders without reducing the expected returns to bidders. Expected benefits of an optimal data-collection program depend on (1) the degree of bidder risk aversion, (2) the expected degree of lease competition and (3) unique lease tract factors that determine economic rents—thickness of seams, proximity to markets, extraction costs, and the spatial correlation characteristics of data. The effects of price uncertainty and government policies affecting market stability on the value of information are also discussed.

Resources and Energy↗

Land-use change and future water demand in California’s central coast

Understanding future land-use related water demand is important for planners and resource managers in identifying potential shortages and crafting mitigation strategies. This is especially the case for regions dependent on limited local groundwater supplies. For the groundwater dependent Central Coast of California, we developed two scenarios of future land use and water demand based on sampling from a historical land change record: a business-as-usual scenario (BAU; 1992–2016) and a recent-modern scenario (RM; 2002–2016). We modeled the scenarios in the stochastic, empirically based, spatially explicit LUCAS state-and-transition simulation model at a high resolution (270-m) for the years 2001–2100 across 10 Monte Carlo simulations, applying current land zoning restrictions. Under the BAU scenario, regional water demand increased by an estimated ~222.7 Mm 3 by 2100, driven by the continuation of perennial cropland expansion as well as higher than modern urbanization rates. Since 2000, mandates have been in place restricting new development unless adequate water resources could be identified. Despite these restrictions, water demand dramatically increased in the RM scenario by 310.6 Mm 3 by century’s end, driven by the projected continuation of dramatic orchard and vineyard expansion trends. Overall, increased perennial cropland leads to a near doubling to tripling perennial water demand by 2100. Our scenario projections can provide water managers and policy makers with information on diverging land use and water use futures based on observed land change and water use trends, helping to better inform land and resource management decisions.

California↗

Aggregate and the environment

This book is designed to help you understand our aggregate resources-their importance, where they come from, how they are processed for our use, the environmental concerns related to their mining and processing, how those concerns are addressed, and the policies and regulations designed to safeguard workers, neighbors, and the environment from the negative impacts of aggregate mining. We hope this understanding will help prepare you to be involved in decisions that need to be made-individually and as a society-to be good stewards of our aggregate resources and our living planet.

Book↗

Mineral resource potential of the Baker-Cypress BLM Instant Study Area and Timbered Crater Forest Service Further Planning (RARE II) Areas, Modoc, Shasta, and Siskiyou Counties, California

In accordance with the provisions of the Federal Land Policy and Management Act (Public Law 94-579, October 21, 1976), the Geological Survey and the Bureau of Mines have conducted mineral surveys on certain areas, which formally had been identified as "natural" and "primitive" areas prior to November 1, 1975. The Wilderness Act (Public Law 88-577, September 3, 1964) and related Acts, r equire the Geological Survey and the Bureau of Mines to survey certain areas on Federal lands to determine their mineral resource potential. Results must be made available to the public and be submitted to the Administration and the Congress. These maps and reports present the results of a geological and mineral survey of the Baker-Cypress BLM Instant Study Area and Timbered Crater Forest Service Further Planning (RARE II) areas. The study areas have no potential for metallic commodities as determined from spectrographic analyses of rocks (Peterson, 1980). Several localities within the study areas, however, contain stone that can be used for decorative purposes in building construction . The study areas may also have geothermal potential, but at this time quantitative data are unavailable.

California↗

Regional impact of water resource investments in an developing area

Regional development and industrialization patterns are investigated and related via regression analysis to water resource investments for the island of Puerto Rico. Although results of this study indicate such investments have little immediate or short‐term impact, significant relationships and variations in regional responses appear over longer time periods. This is shown by applying a variation of Zellner's method of performing seemingly unrelated regressions jointly. By this method, subsets of parameter coefficients of specific economic variables were restricted across regional equations while unrestricted coefficients were interpreted as explaining systematic regional variations in response to public investment. Regional differences, obtained by using this method, are frequently neglected when simply examining the overall development process. Among the more interesting results in terms of policy implications is the apparent significant relationship, over the period considered, between changes in the distribution of income and the pattern of water resource development.

Journal of the American Water Resources Associatio↗

Multiobjective analysis of a public wellfield using artificial neural networks

As competition for increasingly scarce ground water resources grows, many decision makers may come to rely upon rigorous multiobjective techniques to help identify appropriate and defensible policies, particularly when disparate stakeholder groups are involved. In this study, decision analysis was conducted on a public water supply wellfield to balance water supply needs with well vulnerability to contamination from a nearby ground water contaminant plume. With few alternative water sources, decision makers must balance the conflicting objectives of maximizing water supply volume from noncontaminated wells while minimizing their vulnerability to contamination from the plume. Artificial neural networks (ANNs) were developed with simulation data from a numerical ground water flow model developed for the study area. The ANN-derived state transition equations were embedded into a multiobjective optimization model, from which the Pareto frontier or trade-off curve between water supply and wellfield vulnerability was identified. Relative preference values and power factors were assigned to the three stakeholders, namely the company whose waste contaminated the aquifer, the community supplied by the wells, and the water utility company that owns and operates the wells. A compromise pumping policy that effectively balances the two conflicting objectives in accordance with the preferences of the three stakeholder groups was then identified using various distance-based methods. ?? 2006 National Ground Water Association.

Ground Water↗

Everglades Depth Estimation Network (EDEN) Applications: Tools to View, Extract, Plot, and Manipulate EDEN Data

The Everglades Depth Estimation Network (EDEN) is an integrated system of real-time water-level monitoring, ground-elevation data, and water-surface elevation modeling to provide scientists and water managers with current on-line water-depth information for the entire freshwater part of the greater Everglades. To assist users in applying the EDEN data to their particular needs, a series of five EDEN tools, or applications (EDENapps), were developed. Using EDEN's tools, scientists can view the EDEN datasets of daily water-level and ground elevations, compute and view daily water depth and hydroperiod surfaces, extract data for user-specified locations, plot transects of water level, and animate water-level transects over time. Also, users can retrieve data from the EDEN datasets for analysis and display in other analysis software programs. As scientists and managers attempt to restore the natural volume, timing, and distribution of sheetflow in the wetlands, such information is invaluable. Information analyzed and presented with these tools is used to advise policy makers, planners, and decision makers of the potential effects of water management and restoration scenarios on the natural resources of the Everglades.

Fact Sheet↗

Volcanogenic Massive Sulfide Deposits of the World - Database and Grade and Tonnage Models

Grade and tonnage models are useful in quantitative mineral-resource assessments. The models and database presented in this report are an update of earlier publications about volcanogenic massive sulfide (VMS) deposits. These VMS deposits include what were formerly classified as kuroko, Cyprus, and Besshi deposits. The update was necessary because of new information about some deposits, changes in information in some deposits, such as grades, tonnages, or ages, revised locations of some deposits, and reclassification of subtypes. In this report we have added new VMS deposits and removed a few incorrectly classified deposits. This global compilation of VMS deposits contains 1,090 deposits; however, it was not our intent to include every known deposit in the world. The data was recently used for mineral-deposit density models (Mosier and others, 2007; Singer, 2008). In this paper, 867 deposits were used to construct revised grade and tonnage models. Our new models are based on a reclassification of deposits based on host lithologies: Felsic, Bimodal-Mafic, and Mafic volcanogenic massive sulfide deposits. Mineral-deposit models are important in exploration planning and quantitative resource assessments for two reasons: (1) grades and tonnages among deposit types vary significantly, and (2) deposits of different types occur in distinct geologic settings that can be identified from geologic maps. Mineral-deposit models combine the diverse geoscience information on geology, mineral occurrences, geophysics, and geochemistry used in resource assessments and mineral exploration. Globally based deposit models allow recognition of important features and demonstrate how common different features are. Well-designed deposit models allow geologists to deduce possible mineral-deposit types in a given geologic environment and economists to determine the possible economic viability of these resources. Thus, mineral-deposit models play a central role in presenting geoscience information in a useful form to policy makers. The foundation of mineral-deposit models is information about known deposits. The purpose of this publication is to present the latest geologic information and newly developed grade and tonnage models for VMS deposits in digital form. This publication contains computer files with information on VMS deposits from around the world. It also presents new grade and tonnage models for three subtypes of VMS deposits and a text file allowing locations of all deposits to be plotted in geographic information system (GIS) programs. The data are presented in FileMaker Pro and text files to make the information available to a wider audience. The value of this information and any derived analyses depends critically on the consistent manner of data gathering. For this reason, we first discuss the rules used in this compilation. Next, we provide new grade and tonnage models and analysis of the information in the file. Finally, the fields of the data file are explained. Appendix A gives the summary statistics for the new grade-tonnage models and Appendix B displays the country codes used in the database.

Open-File Report↗

Carbonatites of the world, explored deposits of Nb and REE— Database and grade and tonnage models

This report is based on published tonnage and grade data on 58 Nb- and rare-earth-element (REE)-bearing carbonatite deposits that are mostly well explored and are partially mined or contain resources of these elements. The deposits represent only a part of the known 527 carbonatites around the world, but they are characterized by reliable quantitative data on ore tonnages and grades of niobium and REE. Grade and tonnage models are an important component of mineral resource assessments. Carbonatites present one of the main natural sources of niobium and rare-earth elements, the economic importance of which grows consistently. A purpose of this report is to update earlier publications. New information about known deposits, as well as data on new deposits published during the last decade, are incorporated in the present paper. The compiled database (appendix 1; linked to right) contains 60 explored Nb- and REE-bearing carbonatite deposits - resources of 55 of these deposits are taken from publications. In the present updated grade-tonnage model we have added 24 deposits comparing with the previous model of Singer (1998). Resources of most deposits are residuum ores in the upper part of carbonatite bodies. Mineral-deposit models are important in exploration planning and quantitative resource assessments for two reasons: (1) grades and tonnages among deposit types vary significantly, and (2) deposits of different types are present in distinct geologic settings that can be identified from geologic maps. Mineral-deposit models combine the diverse geoscience information on geology, mineral occurrences, geophysics, and geochemistry used in resource assessments and mineral exploration. Globally based deposit models allow recognition of important features and demonstrate how common different features are. Well-designed deposit models allow geologists to deduce possible mineral-deposit types in a given geologic environment, and the grade and tonnage models allow economists to estimate the possible economic viability of these resources. Thus, mineral-deposit models play a central role in presenting geoscience information in a useful form to policy makers. The foundation of mineral-deposit models is information about known deposits. This publication presents the latest geologic information and newly developed grade and tonnage models for Nb- and REE-carbonatite deposits in digital form. The publication contains computer files with information on deposits from around the world. It also contains a text file allowing locations of all deposits to be plotted in geographic information system (GIS) programs. The data are presented in FileMaker Pro as well as in .xls and text files to make the information available to a broadly based audience. The value of this information and any derived analyses depends critically on the consistent manner of data gathering. For this reason, we first discuss the rules used in this compilation. Next, the fields of the database are explained. Finally, we provide new grade and tonnage models and analysis of the information in the file.

Open-File Report↗