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Phytoplankton distribution in three thermally different but edaphically similar reactor cooling reservoirs

Description: Phytoplankton community structure and the physicochemical characteristics of three reactor cooling reservoirs in close proximity and of similar age and bottom type were studied during 1978. The three reservoirs differed in thermal alteration resulting from reactor cooling water as follows: (1) considerable heating with lake-wide temperatures >30/sup 0/C, even in winter; (2) a maximal 5/sup 0/C increase occurring in only one of three major arms of the reservoir; and (3) no thermal effluent received during the study period. Considerable spatial and temporal differences in water quality and phytoplankton community structure were observed; however, water temperature independent of other environmental factors (e.g., light and nutrients) was found to be a relatively unimportant variable for explaining phytoplankton periodicity.
Date: January 1, 1982
Creator: Wilde, E W
Partner: UNT Libraries Government Documents Department

Chlorine demand of Savannah River water

Description: Savannah River water used for cooling SRS reactors was tested for chlorine demand and the rate of decay for both free and total residual chlorine on seven quarterly dates between 1986 and 1988. Test conditions included chlorine dosages of 1, 3, and 5 mg/l and a variety of contact times ranging from less than 1 minute to one day. Statistically significant differences were detected in the chlorine demand for the seven dates; however, there was no discernible seasonality to the variation. The chlorine demand, amount of combined residual chlorine formed and the persistence of total residual chlorine following a dose of 5 mg/l was significantly greater on one of the seven sampling dates (February, 1988) compared to all of the other dates. These differences could not be attributed to water temperature, pH, ammonia nitrogen concentration, or the amount of rainfall prior to or during the collection of the cooling water. Except as noted above, dissipation of chlorine was similar among the sampling dates. Most reactions of available chlorine with other constituents in the cooking water occurred in the first minute of contact, although measurable total chlorine residuals generally persisted for 24 hours after the dose had been administered. The results of this study indicate that, with occasional exceptions, a chlorine dose of between 3 and 5 mg/l will provide a free chlorine residual of 1 mg/l in Savannah River water. 14 refs., 3 figs., 4 tabs.
Date: January 1, 1989
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department

D-Area Drip Irrigation-Phytoremediation Project: SRTC Final Report

Description: Groundwater in D-Area at the Savannah River Site (SRS) is contaminated with trichloroethylene (TCE) and by-products resulting from discharges of this organic solvent during past operations. Several potential clean-up strategies are being or have been investigated, including a novel drip irrigation-phytoremediation process that is the focus of the treatability study described in this report. The contaminated groundwater in D-Area occurs primarily at depths of 30 to 50 feet below ground surface, well below the depths that are typically penetrated by plant roots. The system investigated in this study involved pumping water from the contaminated aquifer and discharging the water into overlying test plots below the surface using drip irrigation. The test plots contained pines, cottonwoods, or no vegetation (controls). The primary objective was to determine the overall effectiveness of the process for TCE removal and to elucidate the biotic and abiotic pathways for its removal.
Date: January 14, 2003
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department

Selecting an Algicide for Use with Aluminum Alloys

Description: This paper discusses the testing and results of five relatively noncorrosive commercially available compounds compared with one another and with sodium hypochlorite for their potential applicability as algicides in water systems containing aluminum alloys.
Date: March 15, 2001
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department

A Simple, Inexpensive in Situ Method for Assessing Acute Toxicity of Effluents to Fish

Description: Test chambers for conducting in situ fish bioassays were constructed from 8L polyethylene bottles. Yearling fathead minnows (Pimephales promelas) and young-of-the-year bluegill (Lepomis macrochirus) demonstrated greater than 50 percent survival in the chambers after 65 days of exposure in a reservoir, river, and creek. Fathead minnow survival was substantially greater than that of bluegills. The chambers provide a simple, inexpensive, sensitive technique to screen effluents for toxicity.
Date: May 29, 2001
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department

Removal of gadolinium nitrate from heavy water

Description: Work was conducted to develop a cost-effective process to purify 181 55-gallon drums containing spent heavy water moderator (D2O) contaminated with high concentrations of gadolinium nitrate, a chemical used as a neutron poison during former nuclear reactor operations at the Savannah River Site (SRS). These drums also contain low level radioactive contamination, including tritium, which complicates treatment options. Presently, the drums of degraded moderator are being stored on site. It was suggested that a process utilizing biological mechanisms could potentially lower the total cost of heavy water purification by allowing the use of smaller equipment with less product loss and a reduction in the quantity of secondary waste materials produced by the current baseline process (ion exchange).
Date: March 22, 2000
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department

Drip Irrigation Aided Phytoremediation for Removal of TCE from Groundwater

Description: Groundwater in D-Area at the Savannah River Site (SRS) is contaminated with trichloroethylene (TCE) and by-products resulting from discharges of this organic solvent during past disposal practices. This contaminated groundwater occurs primarily at depths of 9 meters to 15 meters below ground surface, well below the depths that are typically penetrated by plant roots. The process investigated in this study involved pumping water from the contaminated aquifer and discharging the water into overlying test plots two inches below the surface using drip irrigation. The field treatability study was conducted from 8/31/00 to 4/18/02 using six 0.08 hectare test plots, two each containing pines, cottonwoods, and no vegetation (controls). The primary objective was to determine the overall effectiveness of the process for TCE removal and to determine the principal biotic and abiotic pathways for its removal. Results demonstrated that the process provides a viable method to remove TCE-contaminated groundwater. The data clearly showed that the presence of trees reduced volatilization of TCE from the drip irrigation system to the atmosphere. Influent groundwater TCE concentrations averaging 89 mg/L were reduced to non-detectable levels (less than 5 mg/L) within the upper two feet of soil (rhizosphere).
Date: April 24, 2003
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department

Primary production and biovolume of chroococcoid cyanobacteria in relation to other phytoplankton in southeastern US lakes

Description: Primary production rates and algal biovolumes were measured for various size classes of phytoplankton in three South Carolina lakes. Size classes of less than 3 ..mu..m accounted for 15 to 40% of the total primary production but only represented less than 5% of the total algal biovolume. Fluorescence microscopic analyses and laboratory culturing experiments indicated that chroococcoid cyanobacteria (unicellular blue-green algae) were primarily responsible for the relatively high primary production rates by the less than 3-..mu..m component of the phytoplankton.
Date: January 1, 1979
Creator: Tison, D.L. & Wilde, E.W.
Partner: UNT Libraries Government Documents Department

Effects of K-Reactor pre-operational cold flow testing on total suspended solids in Pen Branch

Description: Total suspended solids (TSS) levels were monitored by SRL Environmental Sciences personnel at two locations in the Pen Branch Creek system in conjunction with K Reactor cold flow (pump) testing required as part of the reactor restart effort. The TSS data were compared with flow and rainfall data collected simultaneously in an effort to obtain insight on the suspension and movement for particulate material in the Pen Branch system in response to natural and operational causes. Pump testing clearly caused higher TSS levels at the two sampling locations. The artificially elevated TSS levels were more pronounced at a sampling location near the reactor than at a sampling location farther downstream. Although the environmental data provided by this study were obtained and used exclusively for process control and research purposes, rather than for formal regulatory compliance (i.e. NPDES monitoring), the TSS levels determined by the comprehensive testing were compared with NPDES limits required at various SRS outfalls. TSS values in Pen Branch were seldom in excess of these limits. Because of the relatively few times that TSS values at the two sampling locations exceeded typical'' NPDES limits, and the fact that occasional relatively high TSS values could clearly be solely attributed to rainfall, it was concluded that no major adverse environmental impacts were caused to the Pen Branch system as a result of the K-Reactor pre-operational pump testing.
Date: December 1, 1991
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department

Microbiological analyses of samples from the H-Area injection well test site

Description: Microbial populations in well water from monitoring wells at the test site were one to three orders of magnitude higher than well water from the Cretaceous aquifer (used as dilution water for the tests) or from a control well adjacent to the test site facility. Coupons samples placed in monitoring and control wells demonstrated progressive adhesion by microbes to materials used in well construction. Samples of material scraped from test well components during abandonment of the test site project revealed the presence of a variety of attached microbes including iron bacteria. Although the injection wells at the actual remediation facility for the F- and H-Area seepage basins remediation project are expected to be subjected to somewhat different conditions (e.g. considerably lower iron concentrations) than was the case at the test site, the potential for microbiologically mediated clogging and fouling within the process should be considered. A sampling program that includes microbiological testing is highly recommended.
Date: May 27, 1997
Creator: Wilde, E.W. & Franck, M.M.
Partner: UNT Libraries Government Documents Department

Immobilization of degradative bacteria in polyurethane-based foams: embedding efficiency and effect on bacterial activity

Description: The immobilization of TCE-degrading bacterium Burkholderia cepacia was evaluated using hydrophilic polyurethane foam. The influence of several foam formulation parameters upon cell retention was examined. Surfactant type was a major determinant of retention, with a lecithin- based compound retaining more cells than pluronic or silicone based surfactants. Excessive amounts of surfactant led to increased washout of bacteria. Increasing the biomass concentration from 4.8% to 10.5% caused fewer cells to be washed out. Embedding at reduced temperature did not significantly affect retention, while the use of a silane binding agent gave inconsistent results. The optimal formulation retained all but 0.2% of total embedded cells during passage of 2 liters of water through columns containing 2 g of foam. All foam formulations tested reduced the culturability of embedded cells by several orders of magnitude. However, O{sub 2} and CO{sub 2} evolution rates of embedded cells were never less than 50% of unembedded cells. Nutrient amendments stimulated an increase in cell volume and ribosomal activity as indicated by hybridization studies using fluorescently labeled ribosomal probes. these results indicated that, although immobilized cells were nonculturable, they were metabolically active and thus could be used for biodegradation of toxic compounds.
Date: September 3, 1996
Creator: Wilde, E.W.; Radway, J.C.; Hazen, T.C. & Hermann, P.
Partner: UNT Libraries Government Documents Department

Test plan for composting studies involving weight and volume reduction of leaf and stalk biomass: DOE/OTD TTP{number_sign} SR17SS53 {ampersand} TTP{number_sign} SR18SS41

Description: SRTC and a panel of experts from off-site previously determined that composting was the most attractive alternative for reducing the volume and weight of biomass that was slightly radioactive. The SRTC proposed scope of work for Subtask 2 of TTP{number_sign} SR17SS53 and TTP{number_sign} SR18SS41 involves bench scale studies to assess the rates and efficiencies of various composting schemes for volume and weight reduction of leaf and stalk biomass (SB). Ultimately, the data will be used to design a composting process for biomass proposed by MSE for phytoremediation studies at SRS. This could drastically reduce costs for transporting and disposing of contaminated biomass resulting from a future major phytoremediation effort for soil clean-up at the site. The composting studies at SRTC includes collaboration with personnel from the University of Georgia, who will conduct chemical analyses of the plant material after harvest, pre-treatment, and composting for specific time periods. Parameters to be measured will include: lignin, hemicellulose, cellulose, carbon and nitrogen. The overall objective of this project is to identify or develop: (1) an inexpensive source of inoculum (consisting of nutrients and/or microorganisms) capable of significantly enhancing biomass degradation, (2) an optimum range of operating parameters for the composting process, and (3) a process design for the solid state degradation of lignocellulosic biomass contaminated with radionuclides that is superior to existing alternatives for dealing with such waste.
Date: May 28, 1997
Creator: Wilde, E.W.; Kastner, J.; Murphy, C. & Santo Domingo, J.
Partner: UNT Libraries Government Documents Department

Par Pond phytoplankton in association with refilling of the pond: Final Report for sampling from February 1995 -- September 1996

Description: This report describes the results of phytoplankton analyses from Par Pond samples collected between February 1995 and September 1996. The principal objective of the study was to determine the effect of refilling of Par Pond following repair of the dam on the phytoplankton community. Algal blooms are often responsible for fish kills and other detrimental effects in ponds and lakes, and it was postulated that decaying vegetation from formerly exposed sediments might trigger algal blooms that could result in fish kills in Par Pond following the refill. Sporadic algal blooms involving blue-green algae were detected, especially during the summer of 1996. However, the data derived from the study demonstrates that overall, the refilling effort caused no significant negative impact to the pond attributable to phytoplankton dynamics.
Date: December 31, 1996
Creator: Wilde, E.W.; Johnson, M.A. & Cody, W.C.
Partner: UNT Libraries Government Documents Department

How to deal with radiologically contaminated vegetation

Description: This report describes the findings from a literature review conducted as part of a Department of Energy, Office of Technology Development Biomass Remediation Task. The principal objective of this project is to develop a process or group of processes to treat radiologically contaminated vegetation in a manner that minimizes handling, processing, and treatment costs. Contaminated, woody vegetation growing on waste sites at SRS poses a problem to waste site closure technologies that are being considered for these sites. It is feared that large sections of woody vegetation (logs) can not be buried in waste sites where isolation of waste is accomplished by capping the site. Logs or large piles of woody debris have the potential of decaying and leaving voids under the cap. This could lead to cap failure and entrance of water into the waste. Large solid objects could also interfere with treatments like in situ mixing of soil with grout or other materials to encapsulate the contaminated sediments and soils in the waste sites. Optimal disposal of the wood includes considerations of volume reduction, treatment of the radioactive residue resulting from volume reduction, or confinement without volume reduction. Volume reduction consists primarily of removing the carbon, oxygen, and hydrogen in the wood, leaving an ash that would contain most of the contamination. The only contaminant that would be released by volume reduction would by small amounts of the radioactive isotope of hydrogen, tritium. The following sections will describe the waste sites at SRS which contain contaminated vegetation and are potential candidates for the technology developed under this proposal. The description will provide a context for the magnitude of the problem and the logistics of the alternative solutions that are evaluated later in the review. 76 refs.
Date: December 31, 1996
Creator: Wilde, E.W.; Murphy, C.E.; Lamar, R.T. & Larson, M.J.
Partner: UNT Libraries Government Documents Department

Microbiologically mediated reduction in the pitting of mild steel overlaid with plywood

Description: Laboratory experiments were conducted to determine the role of microorganisms in the pitting of mild steel flooring, which had been overlaid with plywood. The experimental setups consisted of 4.8 mm (3/16 in.) mild steel plates covered with 12.7 mm (1/2 in.) thick pieces of plywood which were exposed to several different aqueous media supplemented with various combinations of a soil suspension and selected inorganic and organic compounds. Half of the replicate metal-wood-water setups were sterilized and aseptically maintained during incubation after which they were checked for the presence of viable microorganisms and pitting of the mild steel. Results of the first set of experiments showed that pitting of the mild steel specimens in many of these setups occurred after a reasonably short incubation period (3 to 6 months). However, the method used to exclude microorganisms by sterilizing the components separately was unsuccessful. In a second set of experiments, setups were sterilized by exposure to gamma irradiation after they had been assembled. The sterilized setups remained sterile after incubation while those which were not originally sterile still contained viable microorganisms. Pitting of the mild steel specimens was more severe when they were exposed to sterile conditions than when viable microorganisms were present. These experiments showed that while microorganisms are known to enhance corrosion processes in some circumstances, their presence can reduce corrosion in others.
Date: January 1, 1984
Creator: Soracco, R J; Berger, L R; Berger, J A; Mayack, L A; Pope, D H & Wilde, E W
Partner: UNT Libraries Government Documents Department

Bioremediation of aqueous pollutants using biomass embedded in hydrophilic foam. Final report

Description: The major objective of this project was to examine the potential of a novel hydrophilic polyurethane foam as an immobilization medium for algal, bacteria, and other types of biomass, and to test the resulting foam/biomass aggregates for their use in cleaning up waters contaminated with heavy metals, radionuclides and toxic organic compounds. Initial investigations focused on the bioremoval of heavy metals from wastewaters at SRS using immobilized algal biomass. This effort met with limited success for reasons which included interference in the binding of biomass and target metals by various non-target constituents in the wastewater, lack of an appropriate wastewater at SRS for testing, and the unavailability of bioreactor systems capable of optimizing contact of target pollutants with sufficient biomass binding sites. Subsequent studies comparing algal, bacterial, fungal, and higher plant biomass demonstrated that other biomass sources were also ineffective for metal bioremoval under the test conditions. Radionuclide bioremoval using a Tc-99 source provided more promising results than the metal removal studies with the various types of biomass, and indicated that the alga Cyanidium was the best of the tested sources of biomass for this application. However, all of the biomass/foam aggregates tested were substantially inferior to a TEVA resin for removing Tc-99 in comparative testing. The authors also explored the use of hydrophilic polyurethane foam to embed Burkholderia cepacia, which is an efficient degrader of trichloroethylene (TCE), a contaminant of considerable concern at SRS and elsewhere. The embedded population proved to be incapable of growth on nutrient media, but retained respiratory activity. Lastly, the degradative capabilities of embedded G4 were examined. Phenol- or benzene-induced bacteria retained the ability to degrade TCE and benzene. The authors were successful in inducing enzyme activity after the organisms had already been embedded.
Date: December 31, 1996
Creator: Wilde, E. W.; Radway, J. C.; Santo Domingo, J.; Zingmark, R. G. & Whitaker, M. J.
Partner: UNT Libraries Government Documents Department

An evaluation of the ecological consequences of partial-power operation of the K Reactor, SRS

Description: The K Reactor at the Savannah River Site (SRS) shut-down in spring 1988 for maintenance and safety upgrades. Since that time the receiving stream for thermal effluent, Indian Grave Branch and Pen Branch, have undergone a pattern of post-thermal recovery that is typical of other SRS streams following removal of thermal stress. Divesity of fish and aquatic macroinvertebrate communities has increased and available habitats have been colonized by numerous species of herbaceous and woody plants. K Reactor is scheduled to resume operation in 1991 and operate through 1992 without a cooling tower to cool the discharge. It is likely that the reactor will operate at approximately one-third to one-half of full power (800--1200 MW thermal) during this period and effluent temperatures will be substantially lower than earlier operation at full power. Monthly average discharge temperatures at half-power operation will range from approximately 42{degrees}C in winter to 49{degrees}C in summer. The volume of water discharged will not be affected by altered power levels and will average approximately 10--11 m{sup 3}/s. The ecological consequences of this mode of operation on the Indian Grave/Pen Branch stream system have been evaluated.
Date: June 1, 1991
Creator: Gladden, J.B.; Mackey, H.E.; Paller, M.H.; Specht, W.L.; Wike, L.D. & Wilde, E.W.
Partner: UNT Libraries Government Documents Department

Heavy metal removal and recovery using microorganisms

Description: Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding.
Date: February 1, 1991
Creator: Wilde, E.W. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Benemann, J.R. (Benemann (J.R.), Pinole, CA (United States))
Partner: UNT Libraries Government Documents Department

Literature review on the use of bioaccumulation for heavy metal removal and recovery

Description: Bioaccumulation of metals by microbes -- bioremoval'' -- is a powerful new technology for the concentration, recovery, and removal of toxic heavy metals and radionuclides from waste streams and contaminated environments. Algae are particularly well suited for metal bioremoval. A recent commercial application of bioremoval utilizes inert (dead) immobilized microalgae biomass as ion exchange materials for the removal of heavy metals from industrial waste waters. Also, living microalgal cultures have been used to remove metals from mine effluents. Microbial cells and biomass can bioaccumulate metals and radionuclides by a large variety of mechanisms, both dependent and independent of cell metabolism. Microbial cell walls can act as ion exchange and metal complexation agents. Heavy metals can precipitate and even crystallize on cell surfaces. Metabolically produced hydrogen sulfide or other metabolic products can bioprecipitate heavy metals. Many microbes produce both intra- and extracellular metal complexing agents which could be considered in practical metal removal processes. Bioremoval processes are greatly affected by the microbial species and even strain used, pH, redox potential, temperature, and other conditions under which the microbes are grown. Development of practical applications of bioremoval requires applies research using the particular waste solutions to be treated, or close simulations thereof. From a practical perspective, the selection of the microbial biomass and the process for contacting the microbial biomass with the metal containing solutions are the key issues. Much of the recent commercial R D has emphasized commercially available, inert, microbial biomass sources as these can be acquired in sufficient quantities at affordable costs. The fundamental research and practical applications of bioaccumulation by microalgae suggests these organisms warrant a high priority in the development of advanced bioremoval processes.
Date: February 1, 1991
Creator: Benemann, J.R. (Benemann (J.R.), Pinole, CA (United States)) & Wilde, E.W. (Westinghouse Savannah River Co., Aiken, SC (United States))
Partner: UNT Libraries Government Documents Department