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Review of the transport of selected radionuclides in the interim risk assessment for the Radioactive Waste Management Complex, Waste Area Group 7 Operable Unit 7-13/14, Idaho National Engineering and Environmental Laboratory, Idaho

The U.S. Department of Energy (DOE) requested that the U.S. Geological Survey conduct an independent technical review of the Interim Risk Assessment (IRA) and Contaminant Screening for the Waste Area Group 7 (WAG-7) Remedial Investigation, the draft Addendum to the Work Plan for Operable Unit 7-13/14 WAG-7 comprehensive Remedial Investigation and Feasibility Study (RI/FS), and supporting documents that were prepared by Lockheed Martin Idaho Technologies, Inc. The purpose of the technical review was to assess the data and geotechnical approaches that were used to estimate future risks associated with the release of the actinides americium, uranium, neptunium, and plutonium to the Snake River Plain aquifer from wastes buried in pits and trenches at the Subsurface Disposal Area (SDA). The SDA is located at the Radioactive Waste Management Complex in southeastern Idaho within the boundaries of the Idaho National Engineering and Environmental Laboratory. Radionuclides have been buried in pits and trenches at the SDA since 1957 and 1952, respectively. Burial of transuranic wastes was discontinued in 1982. The five specific tasks associated with this review were defined in a ?Proposed Scope of Work? prepared by the DOE, and a follow-up workshop held in June 1998. The specific tasks were (1) to review the radionuclide sampling data to determine how reliable and significant are the reported radionuclide detections and how reliable is the ongoing sampling program, (2) to assess the physical and chemical processes that logically can be invoked to explain true detections, (3) to determine if distribution coefficients that were used in the IRA are reliable and if they have been applied properly, (4) to determine if transport model predictions are technically sound, and (5) to identify issues needing resolution to determine technical adequacy of the risk assessment analysis, and what additional work is required to resolve those issues.

Idaho

Hypothetical modeling of redox conditions within a complex ground-water flow field in a glacial setting

This report describes a modeling approach for studying how redox conditions evolve under the influence of a complex ground-water flow field. The distribution of redox conditions within a flow system is of interest because of the intrinsic susceptibility of an aquifer to redox-sensitive, naturally occurring contaminants - such as arsenic - as well as anthropogenic contaminants - such as chlorinated solvents. The MODFLOW-MT3D-RT3D suite of code was applied to a glacial valley-fill aquifer to demonstrate a method for testing the interaction of flow patterns, sources of reactive organic carbon, and availability of electron acceptors in controlling redox conditions. Modeling results show how three hypothetical distributions of organic carbon influence the development of redox conditions in a water-supply aquifer. The distribution of strongly reduced water depends on the balance between the rate of redox reactions and the capability of different parts of the flow system to transmit oxygenated water. The method can take account of changes in the flow system induced by pumping that result in a new distribution of reduced water.

Scientific Investigations Report

Three-Dimensional Geologic Model of Complex Fault Structures in the Upper Seco Creek Area, Medina and Uvalde Counties, South-Central Texas

This multimedia report shows and describes digital three-dimensional faulted geologic surfaces and volumes of the lithologic units of the Edwards aquifer in the upper Seco Creek area of Medina and Uvalde Counties in south-central Texas. This geologic framework model was produced using (1) geologic maps and interpretations of depositional environments and paleogeography; (2) lithologic descriptions, interpretations, and geophysical logs from 31 drill holes; (3) rock core and detailed lithologic descriptions from one drill hole; (4) helicopter electromagnetic geophysical data; and (5) known major and minor faults in the study area. These faults were used because of their individual and collective effects on the continuity of the aquifer-forming units in the Edwards Group. Data and information were compared and validated with each other and reflect the complex relationships of structures in the Seco Creek area of the Balcones fault zone. This geologic framework model can be used as a tool to visually explore and study geologic structures within the Seco Creek area of the Balcones fault zone and to show the connectivity of hydrologic units of high and low permeability between and across faults. The software can be used to display other data and information, such as drill-hole data, on this geologic framework model in three-dimensional space.

Scientific Investigations Report

Simulation of groundwater and surface-water interaction and effects of pumping in a complex glacial-sediment aquifer, east central Massachusetts

The effects of groundwater pumping on surface-water features were evaluated by use of a numerical groundwater model developed for a complex glacial-sediment aquifer in northeastern Framingham, Massachusetts, and parts of surrounding towns. The aquifer is composed of sand, gravel, silt, and clay glacial-fill sediments up to 270 feet thick over an irregular fractured bedrock surface. Surface-water bodies, including Cochituate Brook, the Sudbury River, Lake Cochituate, Dudley Pond, and adjoining wetlands, are in hydraulic connection with the aquifer and can be affected by groundwater withdrawals. Groundwater and surface-water interaction was simulated with MODFLOW-NWT under current conditions and a variety of hypothetical pumping conditions. Simulations of hypothetical pumping at reactivated water supply wells indicate that captured groundwater would decrease baseflow to the Sudbury River and induce recharge from Lake Cochituate. Under constant (steady-state) pumping, induced groundwater recharge from Lake Cochituate was equal to about 32 percent of the simulated pumping rate, and flow downstream in the Sudbury River decreased at the same rate as pumping. However, surface water responded quickly to pumping stresses. When pumping was simulated for 1 month and then stopped, streamflow depletions decreased by about 80 percent within 2 months and by about 90 percent within about 4 months. The fast surface water response to groundwater pumping offers the potential to substantially reduce streamflow depletions during periods of low flow, which are of greatest concern to the ecological integrity of the river. Results indicate that streamflow depletion during September, typically the month of lowest flow, can be reduced by 29 percent by lowering the maximum pumping rates to near zero during September. Lowering pumping rates for 3 months (July through September) reduces streamflow depletion during September by 79 percent as compared to constant pumping. These results demonstrate that a seasonal or streamflow-based groundwater pumping schedule can reduce the effects of pumping during periods of low flow.

Massachusetts

Completion summary for boreholes USGS 140 and USGS 141 near the Advanced Test Reactor Complex, Idaho National Laboratory, Idaho

In 2013, the U.S. Geological Survey, in cooperation with the U.S. Department of Energy, drilled and constructed boreholes USGS 140 and USGS 141 for stratigraphic framework analyses and long-term groundwater monitoring of the eastern Snake River Plain aquifer at the Idaho National Laboratory in southeast Idaho. Borehole USGS 140 initially was cored to collect continuous geologic data, and then re-drilled to complete construction as a monitor well. Borehole USGS 141 was drilled and constructed as a monitor well without coring. Boreholes USGS 140 and USGS 141 are separated by about 375 feet (ft) and have similar geologic layers and hydrologic characteristics based on geophysical and aquifer test data collected. The final construction for boreholes USGS 140 and USGS 141 required 6-inch (in.) diameter carbon-steel well casing and 5-in. diameter stainless-steel well screen; the screened monitoring interval was completed about 50 ft into the eastern Snake River Plain aquifer, between 496 and 546 ft below land surface (BLS) at both sites. Following construction and data collection, dedicated pumps and water-level access lines were placed to allow for aquifer testing, for collecting periodic water samples, and for measuring water levels. Borehole USGS 140 was cored continuously, starting from land surface to a depth of 543 ft BLS. Excluding surface sediment, recovery of basalt and sediment core at borehole USGS 140 was about 98 and 65 percent, respectively. Based on visual inspection of core and geophysical data, about 32 basalt flows and 4 sediment layers were collected from borehole USGS 140 between 34 and 543 ft BLS. Basalt texture for borehole USGS 140 generally was described as aphanitic, phaneritic, and porphyritic; rubble zones and flow mold structure also were described in recovered core material. Sediment layers, starting near 163 ft BLS, generally were composed of fine-grained sand and silt with a lesser amount of clay; however, between 223 and 228 ft BLS, silt with gravel was described. Basalt flows generally ranged in thickness from 3 to 76 ft (average of 14 ft) and varied from highly fractured to dense with high to low vesiculation. Geophysical and borehole video logs were collected during certain stages of the drilling and construction process at boreholes USGS 140 and USGS 141. Geophysical logs were examined synergistically with the core material for borehole USGS 140; additionally, geophysical data were examined to confirm geologic and hydrologic similarities between boreholes USGS 140 and USGS 141 because core was not collected for borehole USGS 141. Geophysical data suggest the occurrence of fractured and (or) vesiculated basalt, dense basalt, and sediment layering in both the saturated and unsaturated zones in borehole USGS 141. Omni-directional density measurements were used to assess the completeness of the grout annular seal behind 6-in. diameter well casing. Furthermore, gyroscopic deviation measurements were used to measure horizontal and vertical displacement at all depths in boreholes USGS 140 and USGS 141. Single-well aquifer tests were done following construction at wells USGS 140 and USGS 141 and data examined after the tests were used to provide estimates of specific-capacity, transmissivity, and hydraulic conductivity. The specific capacity, transmissivity, and hydraulic conductivity for well USGS 140 were estimated at 2,370 gallons per minute per foot [(gal/min)/ft)], 4.06 × 105 feet squared per day (ft 2 /d), and 740 feet per day (ft/d), respectively. The specific capacity, transmissivity, and hydraulic conductivity for well USGS 141 were estimated at 470 (gal/min)/ft, 5.95 × 104 ft 2 /d, and 110 ft/d, respectively. Measured flow rates remained relatively constant in well USGS 140 with averages of 23.9 and 23.7 gal/min during the first and second aquifer tests, respectively, and in well USGS 141 with an average of 23.4 gal/min. Water samples were analyzed for cations, anions, metals, nutrients, volatile organic compounds, stable isotopes, and radionuclides. Water samples from both wells indicated that concentrations of tritium, sulfate, and chromium were affected by wastewater disposal practices at the Advanced Test Reactor Complex. Most constituents in water from wells USGS 140 and USGS 141 had concentrations similar to concentrations in well USGS 136, which is upgradient from wells USGS 140 and USGS 141.

Idaho

Geology and mineral resources of the Sheldon-Hart Mountain National Wildlife Refuge Complex (Oregon and Nevada), the Southeastern Oregon and North-Central Nevada, and the Southern Idaho and Northern Nevada (and Utah) Sagebrush Focal Areas: Chapter B in Mineral resources of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming

Summary The U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpose of the proposed action is to protect the greater sage-grouse ( Centrocercus urophasianus ) and its habitat from potential adverse effects of locatable mineral exploration and mining. The U.S. Geological Survey Sagebrush Mineral-Resource Assessment (SaMiRA) project was initiated in November 2015 and supported by the Bureau of Land Management to (1) assess locatable mineral-resource potential and (2) to describe leasable and salable mineral resources for the seven SFAs and Nevada additions. This chapter summarizes the current status of locatable, leasable, and salable mineral commodities and assesses the potential of selected locatable minerals in lands proposed for withdrawal that span the Nevada, Oregon, Idaho, and Utah borders. In this report, the four study areas evaluated were (1) the Sheldon-Hart Mountain National Wildlife Refuge Complex SFA in Washoe County, Nevada, and Harney and Lake Counties, Oregon; (2) the Southeastern Oregon and North-Central Nevada SFA in Humboldt County, Nevada, and Harney and Malheur Counties, Oregon; (3) the Southern Idaho and Northern Nevada SFA in Cassia, Owyhee, and Twin Falls Counties, Idaho, Elko County, Nevada, and Box Elder County, Utah; and (4) the Nevada additions in Humboldt and Elko Counties, Nevada.

Idaho, Nevada, Oregon, Utah

Assessing the influence of natural copper-nickel-bearing bedrocks of the Duluth Complex on water quality in Minnesota, 2013–15

The U.S. Geological Survey, in cooperation with the University of Minnesota-Duluth Natural Resources Research Institute, completed an assessment of regional water quality in areas of potential base-metal mining in Minnesota. Bedrock, soil, streambed sediment, and surface-water samples were collected in three watersheds that cross the basal part of the Duluth Complex with different mineral-deposit settings: (1) copper-nickel-platinum group element mineralization (Filson Creek), (2) iron-titanium-oxide mineralization (headwaters of the St. Louis River), and (3) no identified mineralization (Keeley Creek). At least 10 bedrock, 30 soil (2 each from 15 sites), and as many as 13 streambed sediment samples were collected in each watershed and analyzed for 44 major and trace elements, total and inorganic carbon, and 10 loosely bound metals (when possible). Surface-water samples were collected at four to nine locations in each watershed three to four times per year for 2 years (total of 141 environmental samples). Surface-water samples were analyzed for 10 trace metals (total and dissolved concentrations), 8 trace elements, 8 major ions (dissolved concentrations), alkalinity, and total and dissolved organic carbon. Metal and element concentrations in solid media varied by watershed, representing local geology. Copper-nickel sulfide mineralization in the Filson Creek watershed was evidenced in bedrock, soil, and streambed sediments. In the Keeley Creek watershed, silicate mineralogy of underlying bedrock contributed metals to streambed sediments. Thick glacial cover masked potential bedrock contributions to solid media in the St. Louis River watershed. Water-quality data indicate that waters in all three watersheds are dilute. Water quality is more similar between the Filson and Keeley Creek watersheds, compared to the St. Louis River watershed, because of the difference in glacial cover. Metal concentrations (copper and nickel, in particular) in surface-water samples follow similar patterns of concentrations in solid media, indicating the influence of bedrock on water quality in Filson and Keeley Creeks. Data from this study provide a baseline of metal concentrations and general water quality within an area of active mineral exploration.

Minnesota

A conceptual site model of contaminant transport pathways from the Bremerton Naval Complex to Sinclair Inlet, Washington, 2011–21

Historical activities on the Bremerton Naval Complex (BNC) in Puget Sound, Washington, have resulted in Sinclair Inlet sediments with elevated concentrations of contaminants, including organic contaminants such as polychlorinated biphenyls and trace elements including mercury. Six U.S. Geological Survey–U.S. Navy datasets have been collected since the last major assessment, in 2013, of soil and groundwater contaminant transport pathways and mercury loading estimates from the BNC to Sinclair Inlet. These include: mercury isotope analysis to support sourcing of mercury in Sinclair Inlet; mercury sampling within the dry dock systems; nearshore thermal surveys to identify potential groundwater discharge locations to Sinclair Inlet; time-series monitoring in nearshore wells to understand the inland extent and dynamics of the tidal mixing zone; tidal studies of mercury in nearshore monitoring wells in an area of contaminated fill material called Site 1; and a spatial survey of trace elements and other parameters in nearshore monitoring wells, pore water, seeps, surface water, and sediment along unwalled shorelines in the western part of the BNC. The results were incorporated into an updated Conceptual Site Model and used to update contaminant load estimates from the terrestrial BNC to Sinclair Inlet. The results from these studies provide data to the U.S. Navy to support prioritization of on-going remediation actions to manage contamination on the BNC that reduce potential impacts to Sinclair Inlet sediment, surface water, and fish and shellfish tissue. Mercury isotope analysis of surface sediments and particulate material indicated that a similar industrial mercury profile is present throughout Puget Sound, including terrestrial and marine BNC samples and in other Sinclair Inlet sediments and persists across regions with low and elevated mercury concentrations. Two sources of mercury at the BNC are Sites 1 and 2 subsurface soils/fill material, with total mercury concentrations in particulates collected from the bottom of monitoring wells drilled in these materials ranging from 18,000 to 44,000 nanograms per gram (as compared to the Washington State Marine Sediment Cleanup Screening Level of 590 nanograms per gram). Contaminants are transported from the terrestrial BNC to Sinclair Inlet via three primary pathways, (1) stormwater outfalls, (2) dry dock discharges, and (3) direct discharge along unwalled shorelines. Previous loading estimates (based on filtered total mercury) ranked stormwater outfalls, particularly outfall PSNS015 in Site 2 soils, as the largest soil and groundwater contaminant transport pathway from the terrestrial BNC to Sinclair Inlet. Updated loading estimates in this report suggest that the dry dock systems may be a larger pathway of mercury from the terrestrial BNC to Sinclair Inlet than previously thought, within the same order of magnitude as the PSNS015 storm-drain system. Trace-element loads via direct shoreline discharge are difficult to estimate due to the large and dynamic tidal mixing zone of groundwater and seawater in the nearshore along unwalled shorelines. However, current best estimated ranges suggest that direct shoreline discharge is one of the three main pathways and may contribute smaller mercury loads than the stormwater and the dry dock systems. Along unwalled shorelines, direct groundwater discharge of terrestrial contaminants may be less important than recirculating seawater in the nearshore mixing zone that can extract contaminants from nearshore subsurface material. Total estimated mercury loads from the terrestrial BNC to Sinclair Inlet range from approximately 40 to 200 grams of filtered total mercury per year and a minimum of 70–350 grams of particulate total mercury per year, for a minimum total of 110–525 grams of whole (filtered plus particulate) total mercury per year. Data gaps are identified that, if filled, would further refine the Conceptual Site Model and contaminant loading estimates from the terrestrial BNC to Sinclair Inlet.

Washington

Occurrence of cyanobacteria and associated cyanotoxins in the Raritan Basin Water Supply Complex, New Jersey, August 2020 to August 2021

Harmful algal blooms, particularly cyanobacteria harmful algal blooms (cyanoHABs), have emerged as a substantial global concern because of their detrimental effects on water quality and aquatic ecosystem health. CyanoHABs can produce cyanotoxins, which pose serious health risks to humans and wildlife, such as liver failure and respiratory distress. This is particularly concerning for water bodies that serve as drinking-water sources. Recent trends indicate an increase in the frequency and intensity of cyanoHABs globally. This study focuses on the Raritan Basin Water Supply Complex in New Jersey, where extensive monitoring was conducted from August 2020 to August 2021 to assess the presence of cyanobacteria and associated cyanotoxins. The research utilized a combination of discrete water-quality sampling, continuous monitoring, and solid phase adsorption toxin tracking (SPATT) to capture the dynamics of cyanotoxin occurrence and potential transport. Findings revealed a widespread presence of cyanobacteria and potential for cyanotoxin production, although actual cyanotoxin concentrations remained below drinking water and recreational thresholds. The study, conducted by the U.S. Geological Survey (USGS) in collaboration with the New Jersey Water Supply Authority (NJWSA) and the New Jersey Department of Environmental Protection (NJDEP), highlighted the limitations of traditional sampling methods and emphasized that continuous monitoring can support better understanding of how cyanoHAB conditions change over time and in different places. Genetic testing included quantitative polymerase chain reaction (qPCR) analyses, which demonstrated higher sensitivity, or increased findings of cyanobacteria compared to microscopy, indicating the potential for use in early warning systems. This research underscores that integrating various detection methods and hydrological data can enhance understanding of cyanotoxin dynamics in river systems.

New Jersey

Airborne and ground reconnaissance of part of the syenite complex near Wausau, Marathon county, Wisconsin

Airborne and ground reconnaissance for radioactive minerals in part of the syenite complex near Wausau, Marathon county, Wis., found 12 radioactive mineral localities. The rocks in the area are of Precambrian age and consist of syenite and nepheline syenite, which have intruded older granite, greenstone, quartzite, and argillite. There are very few outcrops, and much of the bedrock is deeply weathered and covered by residual soil. Thorium-bearing zircon pegatite float was found within the area of syenite and nepheline syenite at four localities. Reddish-brown euhedral to subeuhedral crystals of well-zoned zircon (variety cyrtolite) comprise more than 40 percent of some of the specimens. The radioactive mineral at four localities outside the area of syneites was identified as thorogummite, which occurred in nodular masses in residual soil. Alinement of the thorogummite float and associated radioactivity suggests that the thorogummite has resulted from weathering of narrow veins or pegmatites containing thorium-bearing minerals. Unidentified thorium-bearing minerals were found at three localities, and a specimen of allanite weighing about 2 pounds was found at one locality. Shallow trenches at two of the largest radioactivity anomalies showed that the radioactive material extended down into weathered bedrock. The occurrences might warrant additional physical exploration should there be sufficient demand for thorium. Further reconnaissance in the area would probably result in the discovery of additional occurrences.

Wisconsin

Water-quality and ground-water hydrology of the Columbia/Eagle Bluffs Wetland Complex, Columbia, Missouri— 1992-99

In an effort to restore riverine wetlands along the Missouri River, the Missouri Department of Conservation constructed the 2,700-acre Eagle Bluffs Conservation Area. The primary water source for managing 1,200 wetland acres on the Eagle Bluffs Conservation Area is treated effluent received from a 91-acre constructed wastewater-treatment wetland operated by the city of Columbia, Missouri. The combined areas of the Eagle Bluffs Conservation Area and the wastewater-treatment wetland are termed the Columbia/Eagle Bluffs Wetland Complex. The U.S. Geological Survey, in cooperation with the Missouri Department of Conservation and the city of Columbia, Missouri, collected samples quarterly from August 1992 to March 1999 from a monitoring network that included 33 ground-water sites and 4 surface-water sites to establish a baseline pre-effluent data set and to provide post-effluent data for trend analysis. Changes in major chemical constituent concentrations have been observed at several sampling locations between pre- and post-effluent data. Analysis of post-effluent time-series water-quality data indicates changes occurred in sodium, potassium, calcium, sulfate, and chloride concentrations at 13 sites. These changes can be correlated to the beginning of the operation of the wastewater-treatment wetland. The concentrations of these major chemical constituents plot on the mixing continuum between pre-effluent ground water as one end member and the treated effluent as the other end member. At ground water sites that had changes in concentrations, the relative percentage of treated effluent in the ground water, assuming chloride is conservative, ranged from 11 to more than 100 percent. At ground-water sites, few changes were noted in fecal indicator bacteria, nutrients, trace constituents, total and dissolved organic carbon, and organic constituents. Other than changes in boron concentrations at one ground-water site, these changes could not be directly correlated to the operation of the treatment wetland or the management of the Eagle Bluffs Conservation Area. After the treatment wetland began operation, improvement in the water quality in Perche Creek was observed. With respect to fecal indicator bacteria and nutrient concentrations, the water quality of water discharging from the Eagle Bluffs Conservation Area was improved relative to the water entering the area. Persistent ground-water highs have been observed beneath the Eagle Bluffs Conservation Area and wastewater-treatment unit 1 following the flooding of the wetland areas. These ground-water highs occur during the fall and winter months when ground- and surface-water levels are high and during the spring and summer months when the water levels are lower. The Missouri River stage had a strong effect on the water levels in the aquifer during pre-effluent conditions, but the effect has been lessened by the ground-water high.

Missouri

Use of RORA for Complex Ground-Water Flow Conditions

The RORA computer program for estimating recharge is based on a condition in which ground water flows perpendicular to the nearest stream that receives ground-water discharge. The method, therefore, does not explicitly account for the ground-water-flow component that is parallel to the stream. Hypothetical finite-difference simulations are used to demonstrate effects of complex flow conditions that consist of two components: one that is perpendicular to the stream and one that is parallel to the stream. Results of the simulations indicate that the RORA program can be used if certain constraints are applied in the estimation of the recession index, an input variable to the program. These constraints apply to a mathematical formulation based on aquifer properties, recession of ground-water levels, and recession of streamflow.

Water-Resources Investigations Report

Salt-water movement in the lower Withlacoochee River-Cross Florida Barge Canal Complex

Construction of the west end of the Cross Florida Barge Canal changed the regimen of the lower Withlacoochee River. The investigation was made to determine how salt water from the Gulf of Mexico moves in the river-canal complex, and how the factors that control salt-water movement--tides and discharge--have changed since canal construction. In the river below the bypass channel, salt water moves inland as a wedge beneath the fresh water with upstream tidal flows and back toward the Gulf with downstream tidal flows. The salt front in the river tends to move farthest upstream near times of relatively high water, or higher high water preceded by relatively high higher low water, especially during of after several days of rising mean tide level.

Florida

Geologic and well-construction data for the H-8 borehole complex near the proposed Waste Isolation Pilot Plant site, southeastern New Mexico

The H-8 complex, a group of three closely-spaced boreholes, is located 9 miles south of the proposed Waste Isolation Pilot Plant site in southeastern Eddy County, New Mexico. The holes were drilled during July, August, and September of 1979 to obtain geologic and hydrologic data to better define the regional ground-water-flow system. The geologic data presented in this report are part of a site-characterization study for the possible disposal of defense-associated radioactive wastes within salt beds of the Salado Formation of Permian age. The geologic data include detailed descriptions of cores, cuttings, and geophysical logs. Each borehole was designed to penetrate a distinct water-bearing zone: H-8a (total depth 505 feet) was completed just below the Magenta Dolomite Member of the Rustler Formation of Permian Age; H-8b (total depth 624 feet) was completed just belows the Culebra Dolomite Member of the Rustler Formation; and H-8c (total depth 808 feet) was completed just below the Rustler Formation-Salado Formation contact. The geologic units penetrated in borehole H-8c are surficial alluvium and eolian sand of Holocene age (0-4 feet); the Mescalero caliche (4-10 feet) and Gatuna Formation (10-153 feet) , both of Pleistocene age; and the Dewey Lake Red Beds (153-399 feet), the Rustler Formation (399-733 feet), and part of the Salado Formation penetrated by borehole H-8c is composed of residue from dissolution of halite and associated rocks, and the hydration of anhydrite to gypsum, indicating that the eastward-moving dissolution front on top of the Salado, found just to the west of the WIPP site, has reached the H-8 site. (USGS)

Water-Resources Investigations Report

Geologic and well-construction data for the H-10 borehole complex near the proposed Waste Isolation Pilot Plant site, southeastern New Mexico

The H-10 borehole complex, a group of three closely spaced boreholes, is located 3 1/2 miles southeast of the proposed Waste Isolation Pilot Plant site in west-central Lea County, New Mexico. The geological data presented in this report are part of a site-characterization study for the possible storage of defense-associated radioactive wastes within salt beds of the Salado Formation of Permian age. Each borehole was designated to penetrate a distinct water-bearing zone: H-10a (total depth 1 ,318 feet) was completed just below the Magenta Dolomite Member of the Rustler Formation of Permian age; H-10b (total depth 1 ,398 feet) was completed just below the Culebra Dolomite Member of the Rustler Formation; and H-10c (total depth 1,538 feet) was completed below the Rustler Formation-Salado Formation contact. The geologic units penetrated in borehole H-10c are surficial alluvium and eolian sand of Holocene age (0-5 feet); the Mescalero caliche (5-9 feet) and the Gatuna Formation (9-90 feet) of Pleistocene age; formation in the Dockum Group (Chinle Formation, 90-482 feet and Santa Rosa Sandstone, 482-658 feet) of Late Triassic age; and the Dewey Lake Red Beds (658-1,204 feet), the Rustler Formation (1,204-1,501 feet), and part of the Salado Formation (1,501-1,538 feet), all of Permian age. The sections of the Rustler and Salado Formations penetrated by borehole H-10c are complete and contain little or no evidence of dissolution of halite and associated rocks, indicating that the eastward-moving dissolution on top of the Salado, found just to the west of the WIPP site, has not reached the H-10 site. (USGS)

Water-Resources Investigations Report

Description and hydrogeologic implications of cored sedimentary material from the 1975 drilling program at the radioactive waste management complex, Idaho

Samples of sedimentary material from interbeds between basalt flows and from fractures in the flows, taken from two drill cores at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory were analyzed for (1) particle-size dribution, (2) bulk mineralogy, (3) clay mineralogy, (4) cation-exchange capacity, and (5) carbonate content. Thin sections of selected sediment material were made for petrographic examination. Preliminary interpretations indicate that (1) it may be possible to distinguish the various sediment interbeds on the basis of their mineralogy, (2) the presence of carbonate horizons in sedimentary interbeds may be utilized to approximate the time of exposure and the climate while the surface was exposed (which affected the hydrogeologic character of the sediment), and the type and orientation of fracture-filling material may be utilized to determine the mechanism by which fractures were filled. (USGS)

Water-Resources Investigations Report

Form and stability of aluminum hydroxide complexes in dilute solution

Laboratory studies of solutions 4.53 x 10 -4 to 4.5 x 10 -5 molal (12.2-1.2 ppm) in aluminum, in 0.01 molal sodium perchlorate, were conducted to obtain information as to the probable behavior of aluminum in natural water. When the solutions were brought to pH 7.5-9.5 and allowed to stand for 24 hours, a precipitate was obtained which was virtually amorphous as shown by X-rays, and which had a solubility equivalent to that of boehmite. This precipitate had a hydrolysis constant (*Ks4) of 1.93 x 10 -13a. When solutions were allowed to stead at this pH range for 10 days, their precipitates gave the X-ray pattern of bayerite (*Ks4 = 1.11 > (10- 4). These hydrolysis constants were obtained at 25?C. and corrected to zero ionic strength and are in close agreement with other published values. The predominant dissolved form in this pH range is Al(OH) -4. Below neutral pH (7.0) the dissolved aluminum species consist of octahedral units in which each aluminum ion is surrounded by six water molecules or hydroxide ions. Single units such as Al(OH2)6 + 3 and AlOH(OH2)5+2 are most abundant below pH 5.0, and where the molar ratio (r) of combined hydroxide to total dissolved aluminum is low. When r is greater than 1.0, polymerization of the octahedral units occurs. When r is between 2.0 and 3.0, solutions aged for 10 days or more contained colloidal particles between 0.10 and 0.45 ? in diameter. Particles whose diameters were greater than 0.10 ? were identified by X-ray diffraction as gibbsite. Particles smaller than 0.10 ? were also present and were shown by means of the electron microscope to have a hexagonal crystal pattern. Structured material consisting of sheets of coalesced six-membered rings of aluminum ions held together by double OH bridges has a distinctive kinetic behavior. This property was used to determine amounts of polymerized material in solutions having r between 1.0 and 3.0 after aging times ranging from a few hours to more than 4 months. Aging increased the size and orderliness of the polymeric aggregates and was accompanied by a decrease in the pH of the solution. The kinetic experiments and stoichiometric data for solutions aged for long periods provided a means of determining activities of polymerized aluminum. From these values the solubility product for microcrystalline gibbsite was determined to be 2.24 x 10 -3, and its free energy of formation, -? 272.3 0.4 kcal per mole. Where polymerization was observed, the process did not stop with small polynuclear complexes containing a few aluminum ions, but proceeded with aging until macromolecules or colloidal-sized particles were formed.

Water Supply Paper

Molecular epidemiology of infectious hematopoietic necrosis virus reveals complex virus traffic and evolution within southern Idaho aquaculture

Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus which infects salmon and trout and may cause disease with up to 90% mortality. In the Hagerman Valley of Idaho, IHNV is endemic or epidemic among numerous fish farms and resource mitigation hatcheries. A previous study characterizing the genetic diversity among 84 IHNV isolates at 4 virus-endemic rainbow trout farms indicated that multiple lineages of relatively high diversity co-circulated at these facilities (Troyer et al. 2000 J Gen Virol. 81:2823-2832). We tested the hypothesis that high IHNV genetic diversity and co-circulating lineages are present in aquaculture facilities throughout this region. In this study, 73 virus isolates from 14 rainbow trout farms and 3 state hatcheries in the Hagerman Valley, isolated between 1978 and 1999, were genetically characterized by sequence analysis of a 303 nucleotide region of the glycoprotein gene. Phylogenetic and epidemiological analyses showed that multiple IHNV lineages co-circulate in a complex pattern throughout private trout farms and state hatcheries in the valley. IHNV maintained within the valley appears to have evolved significantly over the 22 yr study period.

Diseases of Aquatic Organisms