78 Matching Results

Search Results

Advanced search parameters have been applied.

Effects of Heavy, Tracked-Vehicle Disturbance on Forest Soil Properties at Fort Benning, Georgia

Description: The purpose of this report is to describe the effects of heavy, tracked-vehicle disturbance on various measures of soil quality in training compartment K-11 at Fort Benning, Georgia. Predisturbance soil sampling in April and October of 2002 indicated statistically significant differences in soil properties between upland and riparian sites. Soil density was less at riparian sites, but riparian soils had significantly greater C and N concentrations and stocks than upland soils. Most of the C stock in riparian soils was associated with mineral-associated organic matter (i.e., the silt + clay fraction physically separated from whole mineral soil). Topographic differences in soil N availability were highly dependent on the time of sampling. Riparian soils had higher concentrations of extractable inorganic N than upland soils and also exhibited significantly greater soil N availability during the spring sampling. The disturbance experiment was performed in May 2003 by driving a D7 bulldozer through the mixed pine/hardwood forest. Post-disturbance sampling was limited to upland sites because training with heavy, tracked vehicles at Fort Benning is generally confined to upland soils. Soil sampling approximately one month after the experiment indicated that effects of the bulldozer were limited primarily to the forest floor (O-horizon) and the surface (0-10 cm) mineral soil. O-horizon dry mass and C stocks were significantly reduced, relative to undisturbed sites, and there was an indication of reduced mineral soil C stocks in the disturbance zone. Differences in the surface (0-10 cm) mineral soil also indicated a significant increase in soil density as a result of disturbance by the bulldozer. Although there was some tendency for greater soil N availability in disturbed soils, the changes were not significantly different from undisturbed controls. It is expected that repeated soil disturbance over time, which will normally occur in a military training area, would simply intensify the ...
Date: May 20, 2004
Creator: Garten, C.T.,JR.
Partner: UNT Libraries Government Documents Department

DESERT PAVEMENTS AND SOILS ON BASALTIC PYROCLASTIC DEPOSITS AT LATHROP WELLS AND RED CONE VOLCANOES, SOUTHERN NEVADA ABSTRACT

Description: Formation of desert pavement and accretionary soils are intimately linked in arid environments such as the Mojave Desert. Well-sorted fallout scoria lapilli at Lathrop Wells (75-80 ky) and Red Cone ({approx}1 Ma) volcanoes (southern Nevada) formed an excellent starting material for pavement, allowing infiltration of eolian silt and fine sand that first clogs the pore space of underlying tephra and then aggrades and develops vesicular A (Av) horizons. Variations in original pyroclast sizes provide insight into minimum and maximum clast sizes that promote pavement and soil formation: pavement becomes ineffective when clasts can saltate under the strongest winds, while clasts larger than coarse lapilli are unable to form an interlocking pavement that promotes silt accumulation (necessary for Av development). Contrary to predictions that all pavements above altitudes of {approx}400 m would have been ''reset'' in their development after late Pleistocene vegetation advances (about 15 ka), the soils and pavements show clear differences in maturity between the two volcanoes. This indicates that either the pavements/soils develop slowly over many 10,000's of years and then are very stable, or that, if they are disrupted by vegetation advances, subsequent pavements are reestablished with successively more mature characteristics.
Date: August 26, 2005
Creator: Valentine, G.A. & Harrington, C.D.
Partner: UNT Libraries Government Documents Department

Laboratory and Field Evidence for Long-Term Starvation Survival of Microorganisms in Subsurface Terrestrial Environments

Description: BIOGEOCHEMICAL MODELING OF GROUNDWATER FLOW AND NUTRIENT FLUX IN SUBSURFACE ENVIRONMENTS INDICATES THAT INHABITANT MICROORGANISMS EXPERIENCE SEVERE NUTRIENT LIMITATION. USING LABORATORY AND FIELD METHODS, WE HAVE BEEN TESTING STARVATION SURVIVAL IN SUBSURFACE MICROORGANISMS. IN MICROCOSM EXPERIMENTS, WE HAVE SHOWN THAT STRAINS OF TWO COMMONLY ISOLATED SUBSURFACE GENERA, ARTHROBACTER AND PSEUDOMONAS, ARE ABLE TO MAINTAIN VIABILITY IN LOW-NUTRIENT, NATURAL SUBSURFACE SEDIMENTS FOR OVER ONE YEAR. THESE NON-SPORE-FORMING BACTERIA UNDERGO RAPID INITIAL MINIATURIZATION FOLLOWED BY A STABILIZATION OF CELL SIZE. MEMBRANE LIPID PHOSPHOLIPID FATTY ACID (PLFA) PROFILES OF THE PSEUDOMONAS ARE CONSISTENT WITH ADAPTATION TO NUTRIENT STRESS; ARTHROBACTER APPARENTLY RESPONDS TO NUTRIENT DEPRIVATION WITHOUT ALTERING MEMBRANE PLFA. TO TEST SURVIVABILITY OF MICROORGANISMS OVER A GEOLOGIC TIME SCALE, WE CHARACTERIZED MICROBIAL COMMUNITIES IN A SEQUENCE OF UNSATURATED SEDIMENTS RANGING IN AGE FROM MODEM TO {gt}780,000 years. Sediments were relatively uniform silts in Eastern Washington State. Porewater ages at depth (measured by the chloride mass-balance approach) were as old as 3,600 years. Microbial abundance, biomass, and activities (measured by direct counts, culture counts, total PLFAs, and radiorespirometry) declined with sediment age. The pattern is consistent with laboratory microcosm studies of Microbial survival: rapid short-term change followed by long-term survival of a proportion of cells. Even the oldest sediments evinced a small but viable Microbial community. Microbial survival appeared to be a function of sediment age. Porewater age appeared to influence the markup of surviving communities, as indicated by PLFA profiles. Sites with different Porewater recharge rates and patterns of Pleistocene flooding had different communities.
Date: December 31, 1997
Creator: Kieft, T.L.; Murphy, E.M.; Amy, P.S.; Haldeman, D.L. & Ringelberg, D. B.
Partner: UNT Libraries Government Documents Department

Tile Drainage on the Farm

Description: Revised edition. Report discussing the benefits of using tile to solve drainage problems across the United States, including both clay and cement tile. Topics discussed include the ditch digging, methods for laying tile, use of silt basins and sand traps, and lands that require artificial drainage.
Date: 1916
Creator: Smith, Alfred Glace, 1881-
Partner: UNT Libraries Government Documents Department

The Influence of Calcium Carbonate Grain Coatings on Contaminant Reactivity in Vadose Zone Sediments

Description: Calcium carbonate (CaCO3) is widely distributed through the Hanford vadose zone as a minor phase. As a result of current and past geochemical processes, CaCO3 exists as grain coatings, intergrain fill, and distinct caliche layers in select locations. Calcium carbonate may also precipitate when high-level wastes react with naturally Ca- and Mg-saturated Hanford sediments. Calcium carbonate is a very reactive mineral phase. Sorption reactions on its surface may slow the migration of certain contaminants (Co, Sr), but its surface coatings on other mineral phases may diminish contaminant retardation (for example, Cr) by blocking surface reaction sites of the substrate. This project explores the behavior of calcium carbonate grain coatings, including how they form and dissolve, their reactivity toward key Hanford contaminants, their impact (as surface coatings) on the reactivity of other mineral substrates, and on their in-ground composition and minor element enrichment. The importance of CaCO3 as a contaminant sorbent will be defined in all of its different manifestations in Hanford sediments: dispersed minor lithic fragments, pedogenic carbonate coatings on gravel and stringers in silt, and nodules in clay and paleosols. Mass action models will be developed that allow understanding and prediction of the geochemical effects of CaCO3 on contaminant retardation in Hanford sediments.
Date: June 1, 2001
Creator: Zachara, John M.; Chambers, Scott; Brown Jr., Gordon E. & Eggleston, Carrick M.
Partner: UNT Libraries Government Documents Department

DESERT PAVEMENTS AND SOILS ON BASALTIC PYROCLASTIC DEPOSITS AT LATHROP WELLS AND RED CONE VOLCANOES, SOUTHERN NEVADA

Description: Formation of desert pavement and accretionary soils are intimately linked in arid environments such as the Mojave Desert. Well-sorted fallout scoria lapilli at Lathrop Wells (75-80 ky) and Red Cone ({approx}1 Ma) volcanoes (southern Nevada) formed an excellent starting material for pavement, allowing infiltration of eolian silt and fine sand that first clogs the pore space of underlying tephra and then aggrades and develops vesicular A (Av) horizons. Variations in original pyroclast sizes provide insight into minimum and maximum clast sizes that promote pavement and soil formation: pavement becomes ineffective when clasts can saltate under the strongest winds, while clasts larger than coarse lapilli are unable to form an interlocking pavement that promotes silt accumulation (necessary for Av development). Contrary to predictions that all pavements above altitudes of {approx}400 m would have been ''reset'' in their development after late Pleistocene vegetation advances (about 15 ka), the soils and pavements show clear differences in maturity between the two volcanoes. This indicates that either the pavement soils develop slowly over many 10,000's of years and then are very stable, or that, if they are disrupted by vegetation advances, subsequent pavements are reestablished with successively more mature characteristics.
Date: August 10, 2005
Creator: Valentine, G.A. & Harrington, C.D.
Partner: UNT Libraries Government Documents Department

High Resolution Imaging of Vadose Zone Transport using Crosswell Radar and Seismic Methods

Description: Although borehole and outcrops provide some sampling there is a critical need to provide volumetric information between point measurements. For example, there is a need for information on heterogeneities at scales ranging from the centimeter to 10?s of meters, as these features can alter contaminant transport significantly. At Hanford, heterogeneities of interest can range from localized phenomena such as silt or gravel lenses, fractures, clastic dikes, to large-scale lithologic discontinuities. These features have been suspected of leading to funneling and fingering, additional physical mechanisms that could alter and possibly accelerate the transport of contaminants to underlying groundwater. It has also been observed from the studies to date that over relatively short distances there are heterogeneities in the physical structure of the porous medium and structural differences between repacked soil cores and the field site from which the materials initially came. Crosswell geophysical measurements are one means to provide this information.
Date: September 1, 2000
Creator: Majer, Ernest L.; Peterson, John E.; Williams, Kenneth H.; Daley, Thomas M. & Gee, Glendon W.
Partner: UNT Libraries Government Documents Department

Habitat Restoration/Enhancement Fort Hall Reservation : 2008 Annual Report.

Description: Habitat enhancement, protection and monitoring were the focus of the Resident Fisheries Program during 2008. Enhancement and protection included sloping, fencing and planting wetlands plugs at sites on Spring Creek (Head-waters). Many previously constructed instream structures (rock barbs and wing dams) were repaired throughout the Fort Hall Indian Reservation (Reservation). Physical sampling during 2008 included sediment and depth measurements (SADMS) in Spring Creek at the Car Removal site. SADMS, used to track changes in channel morphology and specifically track movements of silt through Bottoms stream systems were completed for 5 strata on Spring Creek. Water temperature and chemistry were monitored monthly on Spring Creek, Clear Creek, Diggie Creek, and Portneuf (Jimmy Drinks) and Blackfoot rivers. Fish population densities and biomass were sampled in five reservation streams which included nine sites. Sampling protocols were identical to methods used in past years. Numbers of fish in Spring Creek series remained relatively low, however, there was an increase of biomass overall since 1993. Salmonid fry densities were monitored near Broncho Bridge and were similar to 2006, and 2007, however, as in years past, high densities of macrophytes make it very difficult to see fry in addition to lack of field technicians. Mean catch rate by anglers on Bottoms streams stayed the same as 2007 at 1.5/hr. Numbers of fish larger than 18-inches caught by anglers increased from 2007 at .20 to .26/hr.
Date: July 23, 2009
Creator: Osborne, Hunter
Partner: UNT Libraries Government Documents Department

Permeation Dispersal of Treatment Agents for In Situ Remediation in Low Permeability Media: 1. Field Studies in Unconfined Test Cells

Description: Chlorocarbons like trichloroethylene (TCE) are common contaminants of concern at US Department of Energy (DOE) facilities and industrial sites across the US and abroad. These contaminants of concern are present in source areas and in soil and ground water plumes as dissolved or sorbed phase constituents as well as dense nonaqueous-phase liquids (DNAPLs). These DNAPL compounds can be released to the environment through a variety of means including leaks in storage tanks and transfer lines, spills during transportation, and land treatment of wastes. When DNAPL compounds are present in low permeability media (LPM) like silt and clay layers or deposits, there are major challenges with assessment of their behavior and implementation of effective in situ remediation technologies. This report describes a field demonstration that was conducted at the Portsmouth Gaseous Diffusion Plant (PORTS) Clean Test Site (CTS) to evaluate the feasibility of permeation and dispersal of reagents into LPM. Various reagents and tracers were injected at seven test cells primarily to evaluate the feasibility of delivery, but also to evaluate the effects of the injected reagents on LPM. The various reagents and tracers were injected at the PORTS CTS using a multi-port injection system (MPIS) developed and provided by Hayward Baker Environmental, Inc.
Date: August 1, 2000
Creator: Siegrist, R.L.; Smuin, D.R.; Korte, N.E.; Greene, D.W.; Pickering, D.A.; Lowe, K.S. et al.
Partner: UNT Libraries Government Documents Department

Baseline Mapping Study of the Steed Pond Aquifer and Crouch Branch Confining Unit Beneath A/M Area, Savannah River Site, Aiken, South Carolina

Description: This report presents the results of a baseline mapping project conducted for the Environmental Restoration Department at Savannah River Site. The purpose of this report is to map the distribution of mud (clay and silt-sized material) within each hydrogeologic unit from the surface down to the top of the Crouch Branch aquifer beneath the A/M Area. The distribution of mud layers and variations in the percentage of clay and silt within the strata is extremely important in order to fully characterize the extent of DNAPL beneath the A/M Area and determine the geometry of the contaminant plumes emanating from them. Precision mapping of these layers can aid in locating areas where contamination is most likely to have migrated into the saturated zone. In addition, this information can be used to refine the current remediation systems or assist in designing new remedial systems.
Date: September 1, 1998
Creator: JACKSON, DENNISG.
Partner: UNT Libraries Government Documents Department

Effect of immiscible liquid contaminants on P-wave transmission through natural aquifer samples

Description: We performed core-scale laboratory experiments to examine the effect of non-aqueous phase liquid (NAPL) contaminants on P-wave velocity and attenuation in heterogeneous media. This work is part of a larger project to develop crosswell seismic methods for minimally invasive NAPL detection. The test site is the former DOE Pinellas Plant in Florida, which has known NAPL contamination in the surficial aquifer. Field measurements revealed a zone of anomalously high seismic attenuation, which may be due to lithology and/or contaminants (NAPL or gas phase). Intact core was obtained from the field site, and P-wave transmission was measured by the pulse-transmission technique with a 500 kHz transducer. Two types of samples were tested: a clean fine sand from the upper portion of the surficial aquifer, and clayey-silty sand with shell fragments and phosphate nodules from the lower portion. Either NAPL trichloroethene or toluene was injected into the initially water-saturated sample. Maximum NAPL saturations ranged from 30 to 50% of the pore space. P-wave velocity varied by approximately 4% among the water-saturated samples, while velocities decreased by 5 to 9% in samples at maximum NAPL saturation compared to water-saturated conditions. The clay and silt fraction as well as the larger scatterers in the clayey-silty sands apparently caused greater P-wave attenuation compared to the clean sand. The presence of NAPLs caused a 34 to 54% decrease in amplitudes of the first arrival. The central frequency of the transmitted energy ranged from 85 to 200 kHz, and was sensitive to both grain texture and presence of NAPL. The results are consistent with previous trends observed in homogeneous sand packs. More data will be acquired to interpret P-wave tomograms from crosswell field measurements, determine the cause of high attenuation observed in the field data and evaluate the sensitivity of seismic methods for NAPL detection.
Date: January 31, 2003
Creator: Geller, Jil T.; Ajo-Franklin, Jonathan B. & Majer, Ernest L.
Partner: UNT Libraries Government Documents Department

STANDARDS CONTROLLING AIR EMISSIONS FOR THE SOIL DESICCATION PILOT TEST

Description: This air emissions document supports implementation of the Treatability Test Plan for Soil Desiccation as outlined in the Deep Vadose Zone Treatability Test Plan for the Hanford Central Plateau (DOE/RL-2007-56). Treatability testing supports evaluation of remedial technologies for technetium-99 (Tc-99) contamination in the vadose zone at sites such as the BC Cribs and Trenches. Soil desiccation has been selected as the first technology for testing because it has been recommended as a promising technology in previous Hanford Site technology evaluations and because testing of soil desiccation will provide useful information to enhance evaluation of other technologies, in particular gas-phase remediation technologies. A soil desiccation pilot test (SDPT) will evaluate the desiccation process (e.g., how the targeted interval is dried) and the long-term performance for mitigation of contaminant transport. The SDPT will dry out a moist zone contaminated by Tc-99 and nitrate that has been detected at Well 299-E13-62 (Borehole C5923). This air emissions document applies to the activities to be completed to conduct the SDPT in the 200-BC-1 operable unit located in the 200 East Area of the Hanford Site. Well 299-E13-62 is planned to be used as an injection well. This well is located between and approximately equidistant from cribs 216-B-16, 216-B-17, 216-B-18. and 216-B-19. Nitrogen gas will be pumped at approximately 300 ft{sup 3}/min into the 299-EI3-62 injection well, located approximately 12 m (39 ft) away from extraction well 299-EI3-65. The soil gas extraction rate will be approximately 150 ft{sup 3}/min. The SDPT will be conducted continuously over a period of approximately six months. The purpose of the test is to evaluate soil desiccation as a potential remedy for protecting groundwater. A conceptual depiction is provided in Figure 1. The soil desiccation process will physically dry, or evaporate, some of the water from the moist zone of interest. ...
Date: September 8, 2010
Creator: MW, BENECKE
Partner: UNT Libraries Government Documents Department

Characterization of 200-UP-1 and 200-ZP-1 Operable Unit Aquifer Sediments and Batch Adsorption Distribution Coefficients for Contaminants of Concern--Fiscal Year 2006 Progress

Description: A total of six core samples from 200-UP/ZP-1 OUs and two additional outcrop samples were characterized during FY2006 by PNNL. One sample (C4971) was identified as slough and not used, but the five other samples identified as intact core samples were used for further analyses. The C4977 sample is gravel-sandy silt and C4990 samples are fine-sandy silt from the Ringold formation. Although the sediments from these two boreholes have similar mineralogical composition, C4990 samples show higher values of Fe oxide content, clay/silt content, and surface area compared those in C4977. The measured Tc Kd values ranged 0–0.2 mg/L for both samples, while U(VI) Kd for C4990 (4.23 mg/L) is much higher than that for C4977 (0.76 mg/L). A key finding from the Kd measurements is that detailed sediment and pore water characterization is necessary to understand the variation in Kd values seen in the empirical batch tests. Without the ancillary characterization of the sediments and pore waters, one might form misleading interpretations of the mechanisms that control the Kd values. Thus, physical, geochemical, and hydrological characterization of the sediments and pore waters should be conducted to increase our understanding of the site-specific Kd measurements. More details for methods and results will be provided in the formal technical report in FY 2007.
Date: September 25, 2006
Creator: Um, Wooyong & Serne, R. Jeffrey
Partner: UNT Libraries Government Documents Department

Carbon Sequestration in Reclaimed Mined Soils of Ohio

Description: Assessment of soil organic carbon (SOC) sequestration potential of reclaimed minesoils (RMS) is important for preserving environmental quality and increasing agronomic yields. The experimental sites were characterized by distinct age chronosequences of reclaimed minesoil and were located in Guernsey, Morgan, Noble, and Muskingum Counties of Ohio. These sites are owned and maintained by Americal Electrical Power. These sites were reclaimed (1) with topsoil application, and (2) without topsoil application, and were under continuous grass or forest cover. In this report results are presented from the sites reclaimed without topsoil application between 1956 and 1969. Three sites are under continuous grass cover and the three under forest cover since reclamation. Three core and three bulk soil samples were collected from each site from three slope positions (upper; middle, and lower) for 0-15 cm and 15-30 cm depths, and texture, pH and electrical conductivity (EC), soil bulk density ({rho}{sub b}), SOC, total nitrogen (TN) stocks were determined. No differences in sand and clay contents, bulk density, SOC and TN stocks were observed within different slope positions within each site. However, sand [R56-G (17.1%) < R69-G (29.1%) = R62-G (29.1%)], and silt [R56-G (58.3%) > R69-G (47.7%)] contents, bulk density [R62-G (1.25 Mg ha{sup -1}) > R69-G (0.94 Mg ha{sup -1}) = R62-G (0.90 Mg ha{sup -1})] varied significantly on the upper slope position among sites under continuous grass cover. Smaller but significant differences were also observed for pH [R69-G (8.3) > R56-G (7.7) = R62-G (7.9)] and EC [R56-G (0.66 dS m{sup -1}) > R62-G (0.25 dS m{sup -1}) = R69-G (0.24 dS m{sup -1})] on upper slope positions among sites under grass. Comparing all sites stochastically, sand and clay contents were similar among all sites except R62-F for both depths. Similarly, soil bulk density was also similar among all sites except ...
Date: January 1, 2005
Creator: Shukla, M.K. & Lal, R.
Partner: UNT Libraries Government Documents Department

Yakima and Touchet River Basins Phase II Fish Screen Evaluation, 2006-2007 Annual Report.

Description: In 2006, Pacific Northwest National Laboratory (PNNL) researchers evaluated 27 Phase II fish screen sites in the Yakima and Touchet river basins. Pacific Northwest National Laboratory performs these evaluations for Bonneville Power Administration (BPA) to determine whether the fish screening devices meet those National Marine Fisheries (NMFS) criteria for juvenile fish screen design, that promote safe and timely passage of juvenile salmonids. The NMFS criteria against which the sites were evaluated are as follows: (1) a uniform flow distribution over the screen surface to minimize approach velocity; (2) approach velocities less than or equal to 0.4 ft/s protects the smallest salmonids from impingement; (3) sweep velocities that are greater than approach velocities to minimize delay of out-migrating juveniles and minimize sediment deposition near the screens; (4) a bypass flow greater than or equal to the maximum flow velocity vector resultant upstream of the screens to also minimize delay of out-migrating salmonids; (5) a gradual and efficient acceleration of flow from the upstream end of the site into the bypass entrance to minimize delay of out-migrating salmonids; and (6) screen submergence between 65% and 85% for drum screen sites. In addition, the silt and debris accumulation next to the screens should be kept to a minimum to prevent excessive wear on screens, seals and cleaning mechanisms. Evaluations consist of measuring velocities in front of the screens, using an underwater camera to assess the condition and environment in front of the screens, and noting the general condition and operation of the sites. Results of the evaluations in 2006 include the following: (1) Most approach velocities met the NMFS criterion of less than or equal to 0.4 ft/s. Of the sites evaluated, 31% exceeded the criterion at least once. Thirty-three percent of flat-plate screens had problems compared to 25% of drum screens. (2) ...
Date: March 1, 2007
Creator: Chamness, Mickie & Tunnicliffe, Cherylyn
Partner: UNT Libraries Government Documents Department

Washington Phase II Fish Diversion Screen Evaluations in the Yakima River Basin, 1997 Annual Report.

Description: The Pacific Northwest National Laboratory evaluated 19 Phase II screen sites in the Yakima River Basin at least three times each between April 30 and August 22, 1997. The sites were examined to determine if they were being effectively operated and maintained to provide fish a safe, efficient return to the river. Data were collected to determine if velocities in front of the screens and in the bypass met current NMFS criteria and promoted timely fish bypass, if fish were protected from injury due to impingement, entrainment, and predation, and whether bypass outfall conditions allowed fish to safely return to the river. A bi-directional flow meter and underwater video system were essential in completing the investigation. In general, water velocity conditions at the screen sites were acceptable by NMFS standards. High approach velocities and slow bypass flow were the most common problems noted. Although velocities often fluctuated from one sampling location to the next, average sweep and approach velocities were very good. In general, fish should not be impinged or experience delays in returning to the river under normal operating conditions. Most screens were properly sealed to prevent fish entrainment and injury, although potential problems were identified at several screen sites. Three sites had gap openings from the forebay to the aftbay, allowing fish to be entrained. Other sites had spaces larger than 3/32 inch where small fish could become trapped. Some drum screens had flat spots but these were not been confirmed as underwater gaps, primarily because of siltation. On rare occasions, seals were intact, but cracked or turned under. Submergence levels at the drum screen sites exceeded 85% for one third of our evaluations. Eight of 12 drum screen sites experienced high water levels during at least one evaluation. Only one operating site's submergence was measured at less ...
Date: February 1, 1998
Creator: Blanton, S.; Neitzel, C. & Abernethy, C. (Pacific Northwest National Laboratory)
Partner: UNT Libraries Government Documents Department

Organic C and N stabilization in a forest soil: evidence from sequential density fractionation

Description: In mineral soil, organic matter (OM) accumulates mainly on and around surfaces of silt- and clay-size particles. When fractionated according to particle density, C and N concentration (per g fraction) and C/N of these soil organo-mineral particles decrease with increasing particle density across soils of widely divergent texture, mineralogy, location, and management. The variation in particle density is explained potentially by two factors: (1) a decrease in the mass ratio of organic to mineral phase of these particles, and (2) variations in density of the mineral phase. The first explanation implies that the thickness of the organic accumulations decreases with increasing particle density. The decrease in C/N can be explained at least partially by especially stable sorption of cationic peptidic compounds (amine, amide, and pyrrole) directly to mineral surfaces, a phenomenon well documented both empirically and theoretically. These peptidic compounds, along with ligand-exchanged carboxylic compounds, could then form a stable inner organic layer onto which less polar organics could sorb more readily than onto the highly charged mineral surfaces (''onion'' layering model). To explore mechanisms underlying this trend in C concentration and C/N with particle density, we sequentially density fractionated an Oregon andic soil at 1.65, 1.85, 2.00, 2.28, and 2.55 g cm{sup -3} and analyzed the six fractions for measures of organic matter and mineral phase properties. All measures of OM composition showed either: (1) a monotonic change with density, or (2) a monotonic change across the lightest fractions, then little change over the heaviest fractions. Total C, N, and lignin phenol concentration all decreased monotonically with increasing density, and {sup 14}C mean residence time (MRT) increased with particle density from ca. 150 y to >980 y in the four organo-mineral fractions. In contrast, C/N, {sup 13}C and {sup 15}N concentration all showed the second pattern. All these data ...
Date: July 15, 2005
Creator: Sollins, P; Swanston, C; Kleber, M; Filley, T; Kramer, M; Crow, S et al.
Partner: UNT Libraries Government Documents Department

Final Report: Model interacting particle systems for simulation and macroscopic description of particulate suspensions

Description: Suspensions of solid particles in liquids appear in numerous applications, from environmental settings like river silt, to industrial systems of solids transport and water treatment, and biological flows such as blood flow. Despite their importance, much remains unexplained about these complicated systems. Mucha's research aims to improve understanding of basic properties of suspensions through a program of simulating model interacting particle systems with critical evaluation of proposed continuum equations, in close collaboration with experimentalists. Natural to this approach, the original proposal centered around collaboration with studies already conducted in various experimental groups. However, as was detailed in the 2004 progress report, following the first year of this award, a number of the questions from the original proposal were necessarily redirected towards other specific goals because of changes in the research programs of the proposed experimental collaborators. Nevertheless, the modified project goals and the results that followed from those goals maintain close alignment with the main themes of the original proposal, improving efficient simulation and macroscopic modeling of sedimenting and colloidal suspensions. In particular, the main investigations covered under this award have included: (1) Sedimentation instabilities, including the sedimentation analogue of the Rayleigh-Taylor instability (for heavy, particle-laden fluid over lighter, clear fluid). (2) Ageing dynamics of colloidal suspensions at concentrations above the glass transition, using simplified interactions. (3) Stochastic reconstruction of velocity-field dependence for particle image velocimetry (PIV). (4) Stochastic modeling of the near-wall bias in 'nano-PIV'. (5) Distributed Lagrange multiplier simulation of the 'internal splash' of a particle falling through a stable stratified interface. (6) Fundamental study of velocity fluctuations in sedimentation. (7) Parallelization of Mucha's 'sort-and-sweep' sedimentation code.
Date: August 30, 2007
Creator: Mucha, Peter J.
Partner: UNT Libraries Government Documents Department

Stormwater Pollution Prevention Plan (SWPPP) for Coal Storage Area Stabilization Project

Description: The scope of this project is to stabilize the abandoned coal storage area and redirect the storm water runoff from sanitary sewer system to the storm drain system. Currently, the existing storm water runoff is directed to a perimeter concrete drainage swale and collected in a containment basin. The collected water is then pumped to a treatment facility and after treatment, is discharged to the Y-12 sanitary sewer system. The existing drainage swale and collection basin along with silt fencing will be used during aggregate placement and grading to provide erosion and sediment control. Inlet protection will also be installed around existing structures during the storm water diversion construction. This project scope will include the installation of a non-woven geotextile fabric and compacted mineral aggregate base (paving optional) to stabilize the site. The geotextile specifications are provided on the vendor cut sheets in Appendix B. The installation of a storm water collection/retention area will also be installed on the southern side of the site in accordance with EPA Technical Guidance on Implementing the Stormwater Runoff Requirements for federal Projects under Section 438 of the Energy Independence and Security Act. The total area to be disturbed is approximately 2.5 acres. The order of activities for this Stormwater Pollution Prevention Plan (SWPPP) will be: (1) post notice of coverage (NOC) in a prominent display near entrance of the site; (2) install rain gauge on site or contact Y-12 Plant Shift Superintendent daily for Met tower rain gauge readings; (3) install stabilized construction exit on site; (4) install silt fencing along perimeter as indicated on the attached site plan; (5) regrade site; (6) install geotextile fabric and compacted mineral aggregate base; (7) install catch basin inlet protection where required; (8) excavate and lower existing catch basin tops, re-grade and asphalt to drain; and ...
Date: March 1, 2011
Creator: Engineering, Project and Design
Partner: UNT Libraries Government Documents Department

Interim measure work plan/design for Agra, Kansas.

Description: This Interim Measure Work Plan/Design (IMWP/D) is supplemental to the Argonne document Interim Measure Conceptual Design for Remediation of Source Area Contamination at Agra, Kansas. The IMWP/D includes information required by Kansas Department of Health and Environment (KDHE) Policy BER-RS-029, Policy and Scope of Work for Interim Measures. Specific to Policy BER-RS-029 is the requirement for several documents that will ensure that an adequate amount and type of data are collected for implementation of the IMWP/D and that data quality and safe conditions are prevailed. Such information is included in the IMWP/D as follows: Appendix A: Data Acquisition Plan--Design Testing Requirements; Appendix B: Basis of Design; Appendix C: Permits; Appendix D: Quality Assurance Project Plan; Appendix E: Health and Safety Plan; and Appendix F: Operations, Maintenance, and Monitoring Schedule. The proposed remedial technology for this project is the installation of five large-diameter boreholes (LDBs) in a source area that has been identified on the property formerly used for grain storage by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA). The goal of the LDB technology is the remediation of the source area by removal of mass quantities of contaminated soil from the vadose zone and treatment of any remaining contaminated soils that are adjacent to the source area to achieve a carbon tetrachloride concentration below 200 {micro}g/kg. Secondary to the soil remediation is the remediation of groundwater at and adjacent to the source areas. The LDB technology serves the following purposes: (1) The physical removal of contaminated soil from the identified source area. (2) Replacement of less permeable native materials (silty clay, clayey silt, and silty sand) with more permeable materials to facilitate the capture of volatilized contaminants in the vertical borehole. (3) Removal of contaminants volatilized by air sparging (AS) and extracted from the vadose zone ...
Date: November 18, 2008
Creator: LaFreniere, L. M.
Partner: UNT Libraries Government Documents Department

Summary of field operations Tijeras Arroyo Well TJA-2. Site-Wide Hydrogeologic Characterization Project

Description: This report is a basic data report for field operations associated with the drilling, logging, completion, and development of Tijeras Arroyo well TJA-2. This test/monitoring well was installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project.
Date: February 1, 1995
Creator: Foutz, W.L. & McCord, J.P.
Partner: UNT Libraries Government Documents Department

Evaluation of dredged material proposed for ocean disposal from MOTBY

Description: The National Park Service, US Department of the Interior requested U.S. Army Corps of Engineers/New York District (USACE-NYD) to evaluate sediments around the Military Ocean Terminal (MOTBY) in Bayonne, New Jersey for unconfined ocean disposal at the Mud Dump Site. Sediment samples were collected from MOTBY. Tests and analyses were conducted on MOTBY sediment core samples. The evaluation of proposed dredged material from MOTBY included grain size and total organic carbon (TOC) analyses and one acute toxicity test with the amphipod Ampelisca abdita. In addition to this benthic toxicity test, a bioaccumulation test (28-day exposure) was conducted.
Date: September 1, 1996
Creator: Barrows, E.S.; Mayhew, H.L. & Word, J.Q.
Partner: UNT Libraries Government Documents Department

Treatment of plutonium contaminated soil/sediment from the Mound site using the ACT*DE*CON{sup SM} process

Description: The removal and/or treatment of contaminated soil is a major problem facing the US DOE. The EG&G Mound Applied Technologies site in Miamisburg, Ohio, has an estimated 1.5 million cubic feet of soils from past disposal and waste burial practices awaiting remediation from plutonium contamination. This amount includes sediment from the Miami-Erie Canal that was contaminated in 1969 following a pipe- rupture accident. Conventional soil washing techniques that use particle separation would generate too large a waste volume to be economically feasible. Therefore, innovative technologies are needed for the cleanup. The ACT*DE*CON process was developed by SELENTEC for washing soils to selectively dissolve and remove heavy metals and radionuclides. ACT*DE*CON chemically dissolves and removes heavy metals and radionuclides from soils and sediments into an aqueous medium. The ACT*DE*CON process uses oxidative carbonate/chelant chemistry to dissolve the contaminant from the sediment and hold the contaminant in solution. The objective of recent work was to document the proves conditions necessary to achieve the Mound-site and regulatory-cleanup goals using the ACT*DE*CON technology.
Date: October 1, 1996
Creator: Negri, M.C.; Swift, N.A. & North, J.P.
Partner: UNT Libraries Government Documents Department