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Integration of Local Knowledge is a Key for the Remediation Success of Legacy Uranium Mine Sites - 19564

A key to success, during all aspects of the remediation process on legacy uranium sites, and easily transferable between countries and projects, is the integration of local knowledge. However, before this knowledge can be integrated, local trust and project understanding must be developed. Local trust and project understanding can only be developed through a principle-centred approach to a shared project vision, two-way communication of knowledge, alignment of project goals, and understanding the local needs early in the remediation process. Once public confidence is obtained, local trust and project understanding must be maintained throughout the entirety of the remediation process. Project understanding is an ongoing endeavor that needs continuous communication and varied methods to succeed. During the management of assessment, remediation, and post remediation monitoring on the Saskatchewan Research Council's CLEANS project (remediation of 37 legacy uranium mine sites in Northern Saskatchewan, Canada), integration of local knowledge has been an instrumental tool attributing to success. During site assessment, integration of local knowledge has included the development and implementation of land use surveys to determine realistic travel and occupancy on and adjacent to these legacy sites, and site specific traditional knowledge and land use studies that have contributed to the development of a detailed knowledge of local land use, resource utilization, country food intake, and human history of the sites. The local knowledge gained during the assessment process is invaluable as it provides information required to support remediation planning, such as: valued ecosystem components, human trophic utilization, length of site occupancy, cultural value assessment, and future land use considerations. During remediation planning, local and traditional knowledge can also be incorporated through determination of plant species suitability for revegetation, development and selection of remediation options, and setting realistic sustainable development targets for local project inclusion. During site remediation operations, local involvement can be utilized through direct labour and equipment, cultural resource monitoring (i.e. archaeological and heritage protection), local logistics and historic information transfer, and stakeholder communications and engagement support. Post remediation, local involvement is an efficient mechanism for long-term monitoring, and care and maintenance activities. Although there may be differences between countries, regions and sites, the remediation process on legacy uranium mines can universally be more successful through the integration of local knowledge; while developing rights/stakeholder engagement and capacity building. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Risk to Ecological Resources on Burial Waste Sites on the Hanford Site, Washington - 20248

The US and other nations have a large nuclear and chemical waste remediation task remaining from World War II, the Cold War, and industrial activities. The US Department of Energy (DOE) has the largest task in the U.S., with Hanford (Washington State) being the most contaminated site, with the longest and most costly cleanup program projected to extend to the end of the century. One of the greatest remediation problems at Hanford are the burial waste facilities, some of which are inside the 200 Areas on the Central Plateau, while others are outside the 200 Areas. These areas are associated with waste sites, pipes, and contaminated trenches, posing technical cleanup challenges to meet DoE's remediation goals, including protection of human health and the environment commensurate with Tri- Party Agreement and current regulatory requirements. In this paper we select one of the legacy waste sites (the BC Cribs and Trenches) as a case study to explore how risk to ecological resources varies during and as a consequence of remediation on sites primarily considered legacy waste sites. We used the risk methodology developed by the Consortium for Risk Evaluation with Stakeholder Participation (CRESP) during the Hanford Site-wide Risk Review. The CRESP methodology included evaluating the risk to receptors, including human health, the Columbia River, groundwater, and ecological and cultural resources. The risk evaluation process for ecological receptors included defining the boundaries of each evaluation unit (EU) to be remediated, definition of a suitable buffer area that might be affected, and consideration of the known resource value based on field work. This information, coupled with known remediation options or strategies, allowed us to develop a risk rating for ecological resources. Site risks were evaluated on a scale of 'not discernible' to 'very high' risk. Consideration of the risks at the buried waste sites was complicated by uncertainties in remediation methods and the degree of restoration that would occur as part of the remediation process. We use the BC Cribs and Trenches as a case study to explore why the risks are low currently but increase during remediation. The current 'not discernible to low' risk rating is due to the lack of high quality ecological resources on the BC Cribs and Trenches EU, except for edge areas (with some state-listed species). During remediation the risks increase to 'medium', mainly due to high quality resources on adjacent buffer lands, which could be disrupted during active remediation. Medium and high quality resources on the edge of the site are continuous with higher quality native shrub-steppe habitat on the buffer. Ecological resources on some of the areas surrounding the 200 East and West Areas are some of the highest quality shrub-steppe areas on the Hanford Site, and risk to these resources could be prevented by planning before and during remediation to minimize disruption. For example, lay down areas for the BC Cribs and Trenches can be minimized by careful planning. Heavy truck and other vehicular traffic can be minimized. Spread of the noxious weeds now on some of the site can be prevented, and the spread of invasive species into the site (particularly near undisturbed shrub-steppe habitat) can be reduced. Further, the areas around and between the 200 East and West Areas have been largely undisturbed and can serve as a source of seeds and propagules for any revegetation that occurs as part of the remediation process. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Functional activity and functional gene diversity of a Cu-contaminated soil remediated by aided phytostabilization using compost, dolomitic limestone and a mixed tree stand

Trace elements (TEs) availability, biochemical activity and functional gene diversity was studied in a Cu-contaminated soil, revegetated for six years with a mixed stand of willow, black poplar, and false indigo-bush, and amended or not with compost plus dolomitic limestone (OMDL). The OMDL amendment significantly reduced Cu and As availability and soil toxicity, and increased the biochemical activity and microbial functional diversity assessed with the GEOCHIP technique, as compared to the unamended soil (Unt). The OMDL soil showed significantly higher abundance of 25 functional genes involved in decomposition organic compounds, and 11, 3 and 11 functional genes involved in the N, P and S biogeochemical cycles. Functional gene abundance was positively correlated with nutrient contents but negatively correlated with Cu availability and soil toxicity. The abundance of microbial functional genes encoding for resistance to various TEs also increased, possibly due to the microbial proliferation and lower Cu exposure in the presence of high total soil Cu concentration. Genes encoding for antibiotic resistance due to the co-occurrence of TEs and antibiotic resistant genes on genetic mobile elements. Finally, overall, phytomanagement confirmed its potential to restore the biological fertility and diversity of a severely Cu-contaminated soil, but the increase of TEs and antibiotic resistant gene abundances deserve attention in future studies.

54 ENVIRONMENTAL SCIENCES↗

Optimization of Structural Flood Mitigation Strategies

The dynamics of flooding are primarily influenced by the shape, height, and roughness (friction) of the underlying topography. For this reason, mechanisms to mitigate floods frequently employ structural measures that either modify topographic elevation, for example, through the placement of levees and sandbags, or increase roughness, for example, through revegetation projects. However, the configuration of these measures is typically decided in an ad hoc manner, limiting their overall effectiveness. The advent of high–performance surface–water modeling software and improvements in black–box optimization suggest that a more principled design methodology may be possible. This paper proposes a new computational approach to the problem of designing structural mitigation strategies under physical and budgetary constraints. It presents the development of a problem discretization amenable to simulation–based, derivative–free optimization. However, meta–heuristics alone are found to be insufficient for obtaining quality solutions in a reasonable amount of time. As a result, this paper proposes novel numerical and physics–based procedures to improve convergence to a high–quality mitigation. Furthermore the efficiency of the approach is demonstrated on hypothetical dam break scenarios of varying complexity under various mitigation budget constraints. In particular, experimental results show that, on average, the final proposed algorithm results in a 65% improvement in solution quality compared to a direct implementation.

54 ENVIRONMENTAL SCIENCES↗

AmeriFlux US-Dmg Dutch Slough Marsh Gilbert Tract

This is the AmeriFlux version of the carbon flux data for the site US-Dmg Dutch Slough Marsh Gilbert Tract. Site Description - A new restored tidal freshwater wetland located on the west Delta, within Oakley, CA. The tower is located in the eastern side of the Gilbert Parcel seeing the mid marsh transition zone upwind. Restoration work is done by DWR and started in 2018, revegetation planting started in late 2019, followed by tidal action restoration in October 2021.

Arias-Ortiz, Ariane↗

AmeriFlux FLUXNET-1F US-Dmg Dutch Slough Marsh Gilbert Tract

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Dmg Dutch Slough Marsh Gilbert Tract. This is the FLUXNET version of the carbon flux data for the site US-Dmg Dutch Slough Marsh Gilbert Tract produced by applying the standard ONEFlux (1F) software. Site Description - A new restored tidal freshwater wetland located on the west Delta, within Oakley, CA. The tower is located in the eastern side of the Gilbert Parcel seeing the mid marsh transition zone upwind. Restoration work is done by DWR and started in 2018, revegetation planting started in late 2019, followed by tidal action restoration in October 2021.

Arias-Ortiz, Ariane↗

Monitoring Soil Erosion on a Burned Site in the Mojave-Great Basin Transition Zone: Final Report for the Jacob Fire Site

A historic return interval of 100 years for large fires in the U.S. southwestern deserts is being replaced by one where fires may reoccur as frequently as every 20 to 30 years. The shortened return interval, which translates to an increase in fires, has implications for management of Soil Corrective Action Units (CAUs) and Corrective Action Sites (CASs) for which the Department of Energy, National Nuclear Security Administration Nevada Field Office has responsibility. A series of studies was initiated at uncontaminated analog sites to better understand the possible impacts of erosion and transport by wind and water should contaminated soil sites burn. The first of these studies was undertaken at the Jacob Fire site approximately 12 kilometers (7.5 miles) north of Hiko, Nevada. A lightning-caused fire burned approximately 200 hectares during August 6-8, 2008. The site is representative of a transition between Mojave and Great Basin desert ecoregions on the Nevada National Security Site (NNSS), where the largest number of Soil CAUs/CASs are located. The area that burned at the Jacob Fire site was primarily a Coleogyne ramosissima (blackbrush) and Ephedra nevadensis (Mormon tea) community, also an abundant shrub assemblage in the similar transition zone on the NNSS. This report summarizes three years of measurements after the fire. Seven measurement campaigns at the Jacob Fire site were completed. Measurements were made on burned ridge (upland) and drainage sites, and on burned and unburned sites beneath and between vegetation. A Portable In-Situ Wind Erosion Lab (PI-SWERL) was used to estimate emissions of suspended particles at different wind speeds. Context for these measurements was provided through a meteorological tower that was installed at the Jacob Fire site to obtain local, relevant environmental parameters. Filter samples, collected from the exhaust of the PI-SWERL during measurements, were analyzed for chemical composition. Runoff and water erosion were quantified through a series of rainfall/runoff simulation tests in which controlled amounts of water were delivered to the soil surface in a specified amount of time. Runoff data were collected from understory and interspace soils on burned ridge and drainage areas. Runoff volume and suspended sediment in the runoff were sampled; the particle size distribution of the sediment was determined by laboratory analysis. Several land surface and soil characteristics associated with runoff were integrated by the calculation of site-specific curve numbers. Several vegetation surveys were conducted to assess post-burn recovery. Data from plots in both burned and unburned areas included species identification, counts, and location. Characterization of fire-affected area included measures at both the landscape scale and at specific sites. Although wind erosion measurements indicate that there are seasonal influences on almost all parameters measured, several trends were observed. PI-SWERL measurements indicated the potential for PM 10 windblown dust emissions was higher on areas that were burned compared to areas that were not. Among the burned areas, understory soils in drainage areas were the most emissive, and interspace soils along burned ridges were least emissive. By 34 months after the burn (MAB), at the end of the study, emissions from all burned soil sites were virtually indistinguishable from unburned levels. Like the amount of emissions, the chemical signature of the fire (indicated by the EC-Soil ratio) was elevated immediately after the fire and approached pre-burn levels by 24 MAB. Thus, the potential for wind erosion at the Jacob Fire site, as measured by the amount and type of emissions, increased significantly after the fire and returned to unburned levels by 24 MAB. The effect of fire on the potential for water erosion at the Jacob Fire site was more ambiguous. Runoff and sediment from ridge interspace soils and unburned interspace soils were similar throughout the study period. Seldom, if ever, did runoff and sediment occur in burned drainage area soils. For burned soils where runoff occurred at 1 MAB, the sediment size was finer than on unburned sites, but this effect disappeared by 3 MAB. For the three year study under the conditions tested at the Jacob Fire site, the potential for water erosion appeared relatively unaffected by the fire. Vegetation responses were documented for each year following the fire. By the end of the study, there was a substantial difference in plant densities and richness between drainage and ridge sites. Cheatgrass densities were higher in unburned plots, and cheatgrass was also more dominant in the community composition in unburned plots. Cheatgrass had increased in the burned area but so did other native species. Three years after the fire, the burned landscape continued to revegetate but had yet to approximate the condition of an unburned landscape. The results from the vegetation surveys support the wind erosion results, where the primary source of windborne particles originate from the understory, where lower plant diversity and densities were found. The soil appears to be more resilient and have a much shorter recovery time than the vegetation in this particular community.

54 ENVIRONMENTAL SCIENCES↗

Nevada National Security Site 2015 Waste Management Monitoring Report Area 3 and Area 5 Radioactive Waste Management Sites

Environmental monitoring data are collected at and around the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) within the Nevada National Security Site (NNSS). These data include direct radiation exposure, as well as radiation from the air, groundwater, meteorology, and vadose zone. This report summarizes the 2015 environmental data to provide an overall evaluation of RWMS performance and to support environmental compliance and performance assessment (PA) activities. Some of these data (e.g., radiation exposure, air, and groundwater) are presented in other reports developed by National Security Technologies, LLC. Direct radiation monitoring data indicate exposure levels at the RWMSs are within the range of background levels measured at the NNSS. Slightly elevated exposure levels outside the Area 3 RWMS are attributed to nearby historical aboveground nuclear weapons tests. Air monitoring data show that tritium concentrations in water vapor and americium and plutonium concentrations in air particles are below Derived Concentration Standards for these radionuclides. Groundwater monitoring data indicate the groundwater in the uppermost aquifer beneath the Area 5 RWMS is not impacted by RWMS operations. Results of groundwater analysis from wells around the Area 5 RWMS were all below established investigation levels. Leachate samples collected from the leachate collection system at the mixed low-level waste cell were below established contaminant regulatory limits. During 2015, precipitation at the Area 3 RWMS was 0.9% above average, and precipitation at the Area 5 RWMS was 25% above average. Water balance measurements indicate that evapotranspiration from the vegetated weighing lysimeter dries the soil and prevents downward percolation of precipitation more effectively than evaporation as measured from the bare-soil weighing lysimeter. The 1.8 inches of precipitation in September reached the lowest sensors at 180 cm on the Cell 5S and 5N covers, however the sensors on the floor do not indicate any signs of the precipitation percolating thru the waste to the floor. Moisture from precipitation did not percolate below 150 centimeters (cm) (5 feet [ft]) in the vegetated final cover on the U-3ax/bl disposal unit at the Area 3 RWMS. A second remedial revegetation trial was done on the southern portion of the North Cover. In March 2015 it was determined that germination occurred on both the mulched and non-mulched treatments that were irrigated, but that no germination occurred on the non-irrigated treatments. By June the seedlings observed in March were gone, possibly grazed by rabbits which were observed inside the rabbit-proof fence. In August the entire area was sprayed with the herbicide glyphosate in an attempt to minimize weed seed production. During 2015, there was no drainage through 2.4 meters (8 ft) of soil as indicated from the Area 3 drainage lysimeters that received only natural precipitation. Thirty-one percent of the applied precipitation and irrigation drained from the bare-soil drainage lysimeter, which received 3 times the natural precipitation. All 2015 monitoring data indicate that the Area 3 and Area 5 RWMSs are performing within expectations of the model and parameter assumptions for the facilities’ PAs.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Mixed Waste Landfill Annual Long-Term Monitoring & Maintenance Report April 2016-March 2017

Sampling activities for this reporting period included two semiannual monitoring events each for groundwater, soil-vapor, and radon. Annual soil-moisture monitoring was conducted in April 2016, annual tritium surface soil sampling was conducted in August 2016, and annual biota sampling (metals and radionuclides) was conducted in September 2016. All monitoring activities were conducted in accordance with LTMMP requirements and no monitoring results exceeded LTMMP trigger levels. All monitoring results were consistent with historic MWL monitoring data. Inspections of the MWL final cover system, storm-water diversion structures, compliance monitoring systems, and security fence were performed in accordance with LTMMP requirements. Required maintenance and repairs were minor and were generally performed during the inspections. The Evapotranspirative (ET) Cover continues to meet successful revegetation criteria and is in excellent condition with even coverage of mature, native perennial grasses. Maintenance was performed during the reporting period as a best management practice for ET Cover vegetation, and included a lower level of effort relative to previous years. The purpose of ongoing ET Cover maintenance efforts is to promote the growth and health of the desired native grass species by reducing competition with weedy species for limited moisture and nutrients. Based on previous inspections, additional best management practice activities were conducted during this reporting period to improve the site and reduce long-term ET Cover and site maintenance. These activities included improvements to site access and drainage (i.e., improvements to the access and perimeter road) and the installation of erosion and burrow control measures at the ten perimeter monitoring well locations.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

2018 Long-Term Hydrologic Monitoring Program for Rio Blanco, Colorado, Site

This report for the third quarter (July 1–September 30) of calendar year (CY) 2018 includes information on the remedy-related surveillance, monitoring, and maintenance activities conducted at the Rocky Flats Site, Colorado. This report summarizes the maintenance and inspection of the two site landfills and four groundwater collection or treatment systems, inspection of the perimeter signs of the Central Operable Unit, erosion control and revegetation activities, and water monitoring.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Soil Microbiome Dynamics During Pyritic Mine Tailing Phytostabilization: Understanding Microbial Bioindicators of Soil Acidification

Challenges to the reclamation of pyritic mine tailings arise from in situ acid generation that severely constrains the growth of natural revegetation. While acid mine drainage (AMD) microbial communities are well-studied under highly acidic conditions, fewer studies document the dynamics of microbial communities that generate acid from pyritic material under less acidic conditions that can allow establishment and support of plant growth. This research characterizes the taxonomic composition dynamics of microbial communities present during a 6-year compost-assisted phytostabilization field study in extremely acidic pyritic mine tailings. A complementary microcosm experiment was performed to identify successional community populations that enable the acidification process across a pH gradient. Taxonomic profiles of the microbial populations in both the field study and microcosms reveal shifts in microbial communities that play pivotal roles in facilitating acidification during the transition between moderately and highly acidic conditions. The potential co-occurrence of organoheterotrophic and lithoautotrophic energy metabolisms during acid generation suggests the importance of both groups in facilitating acidification. Taken together, this research suggests that key microbial populations associated with pH transitions could be used as bioindicators for either sustained future plant growth or for acid generation conditions that inhibit further plant growth.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Application of ERTS-A imagery to fracture related mine safety hazards in the coal mining industry

The author has identified the following significant results. The most important result to date is the demonstration of the special value of repetitive ERTS-1 multiband coverage for detecting previously unknown fracture lineaments despite the presence of a deep glacial overburden. The Illinois Basin is largely covered with glacial drift and few rock outcrops are present. A contribution to the geological understanding of Illinois and Indiana has been made. Analysis of ERTS-1 imagery has provided useful information to the State of Indiana concerning the surface mined lands. The contrast between healthy vegetation and bare ground as imaged by Band 7 is sharp and substantial detail can be obtained concerning the extent of disturbed lands, associated water bodies, large haul roads, and extent of mined lands revegetation. Preliminary results of analysis suggest a reasonable correlation between image-detected fractures and mine roof fall accidents for a few areas investigated. ERTS-1 applications to surface mining operations appear probable, but further investigations are required. The likelihood of applying ERTS-1 derived fracture data to improve coal mine safety in the entire Illinois Basin is suggested from studies conducted in Indiana.

Wier, C. E.↗

Identification of geostructures of continental crust particularly as they relate to mineral resource evaluation

The author has identified the following significant results. New mineral deposits have recently been discovered in eastern Alaska through application of a hypothesis very similar to one developed in interpretation of Nimbus and ERTS-1 imagery in this investigation, that mineral deposits may be spatially related to a set of crustal linears. The discovery affirms the validity of this hypothesis and provides an additional exploration rationale to the mineral industry. A regional lineation in lakes near Umiat in northern Alaska, suspected to reflect structures in basement and suggesting areas of possible potential for new petroleum exploration, is found to cover a much larger area than previously suspected east of the Colville River, increasing the area of interest. Further application of this same imagery exists in that environmental scars to the tundra resulting from previous ground exploration, if of large size, can be recognized and their natural revegetation monitored by use of ERTS imagery. New geologic data obtained from ERTS-1 images of lowland areas of western northern Alaska facilitates assessing the petroleum potential of this area. Use of the images in field mapping permitted extrapolation of field observations. Mosaics of ERTS-1 images have provided additional data on regional linear sets and on other regional fault trends possibly related to mineralized areas.

Gryc, G.↗

Analysis of state of vehicular scars on Arctic Tundra, Alaska

Identification on ERTS images of severe vehicular scars in the northern Alaska tundra suggests that, if such scars are of an intensity or have spread to a dimension such that they can be resolved by ERTS sensors (20 meters), they can be identified and their state monitored by the use of ERTS images. Field review of the state of vehicular scars in the Umiat area indicates that all are revegetating at varying rates and are approaching a stable state.

Lathram, E. H.↗

The use of color infrared imagery for the study of marsh buggy tracks

Color infrared imagery is used to determine the location of buggy routes and to quantify the extent of tracks in a selected area where the marsh is seriously dissected. The imagery is used to show successive stages of destruction. It is recommended that alternate routes be identified in the operating area to eliminate continuous use of the same route and facilitate faster revegetation.

Whitehurst, C. A.↗

A demonstration of ERTS-1 analog and digital techniques applied to strip mining in Maryland and West Virginia

The largest contour strip mining operations in western Maryland and West Virginia are located within the Georges Creek and the Upper Potomac Basins. These two coal basins lie within the Georges Creek (Wellersburg) syncline. The disturbed strip mine areas were delineated with the surrounding geological and vegetation features using ERTS-1 data in both analog (imagery) and digital form. The two digital systems used were: (1) the ERTS-Analysis system, a point-by-point digital analysis of spectral signatures based on known spectral values, and (2) the LARS Automatic Data Processing System. The digital techniques being developed will later be incorporated into a data base for land use planning. These two systems aided in efforts to determine the extent and state of strip mining in this region. Aircraft data, ground verification information, and geological field studies also aided in the application of ERTS-1 imagery to perform an integrated analysis that assessed the adverse effects of strip mining. The results indicated that ERTS can both monitor and map the extent of strip mining to determine immediately the acreage affected and indicate where future reclamation and revegetation may be necessary.

Anderson, A. T.↗

Predict ephemeral and perennial range quantity and quality during normal grazing season

The author has identified the following significant results. Collection and update of resource inventory data has historically been a difficult, time consuming task. Accurate resource data is necessary as a basis for wise management decisions made by a resource management agency such as the Bureau of Land Management. Black and white and color infrared composites of ERTS satellite imagery at 1:1,000,000 and enlarged scales can be used as data gathering tools. No investment in expensive sophisticated equipment is necessary. A photointerpreter can map boundaries of soils, plant communities, levels of forage production, areas revegetated by man, and areas burned by wildlife directly from satellite imagery. The ERTS system of producing and distributing imagery must be improved greatly before satellite imagery can be useful to the resource manager.

Bentley, R. G., Jr.↗

Selenium in soils of the Lower Wasatch Formation, Campbell County, Wyoming: Geochemistry, distribution, and environmental hazards

The author has identified the following significant results. Seleniferous Shingle series soils and sandstone outcrops of section 27, T 48 N, R 71 W, Wyoming are mapped on aerial photography by their association with Astragalus bisulcatus. Chemical leachate analyses and atomic absorption methods reveal all studied Samsil and Shingle soils to contain acid, base, and water soluble selenium compounds, and that water extractions showed varied concentration behavior due to soil pH. Acid-soluble selenium is found to be associated with smectite. Statistical analyses confirm that A. bisulcatus presence has a weak influence on soil-lens organic selenium concentration, and determine the importance of other geobotanical factors for convertor presence. Environmental procedures of high selenium lens burial, convertor plant eradication, and revegetated site monitoring are recommended. Usage of density analysis and photographic enlargement are used to successfully produce both a control area and a Campbell County, Wyoming regional map of A. bisulcatus supportive soils and outcrops using Skylab photography.

Kolm, K. E.↗