Browsing Bulletins, Virginia Water Resources Research Center by Title
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- The 1986 amendments to the Safe Drinking Water Act : impacts on Virginia's water supply industryCox, William E.; Sherrard, Joseph H.; Gaw, Christopher D. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1991-10)
- Adsorption of metal ions and metal complexes on mineralsDillard, John G.; Crowther, D. (Deborah L.); Schenck, Catherine V. (Catherine Virginia), 1956- (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1984-06)
- Adsorption of organic compounds onto solids from aqueous solutionsWightman, James P.; Dole, Leslie R.; Jones, J.; King, Clarence A. (Water Resources Research Center, Virginia Polytechnic Institute and State University, 1971)The use of solids to remove pollutants is not novel in the sense that solids are used presently for this purpose. For example, the use of charcoal is well known, and the use of alumina in phosphate removal has been investigated. The removal of phenol from aqueous solutions on a variety of solids has been studied in this work. The rationale for this study is as follows. An aqueous solution containing a pollutant (phenol) is a three component system consisting of a solute (phenol) and solvent (water) in contact with a solid. The question arises, what about the removal of the pollutant by the solid? In many instances the kinds of solids that have been used are those which not only compete for the pollutant, but also compete for water. Thus, not only is the interaction between the pollutant and the solid important, but also the Interaction between the water and the sol id. In many systems, for example herbicides, insecticides, and phenol, there is a Iimited solute concentration, which means that there is a basic incompatability in the system to start with. Then as this solution is put in contact with a solid surface, the amount of pollutant and the amount of water removed become relevant. If the solid has an attraction for water in addition to the pollutant, water may be removed and block parts of the solid which could be effective in removing the pollutant. This study has been concerned with the adsorption of phenol from aqueous solutions on several solids chosen to alter the competition of water and phenol for the surface of the solid.
- Agricultural land use : effects on the chemical quality of runoffSmolen, M. D.; Shanholtz, Vernon O. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1980)This research is the first phase of the Blackstone Environmental Quality Program, a study to distinguish the water quality effects of agricultural practices. Th is research focused on changes in runoff quaIity when land is put under cultivation. The data will be used in later phases of the program to evaluate chemical transport models. The three study watersheds, located in Virginia's southern Piedmont, had not been under cultivation for 30 years. During the research, two of the watersheds were put into agricultural production while the third was left uncultivated and used as a control. A grab sampling program was maintained on two watersheds for the full five-year period of study. Continuous streamflow gaging was maintained for the last four years. During the final three years, sampling and flow gaging were also maintained on a third watershed. For those three years, grab sampling was supplemented by automatic samplers for stormflow sample collection. Samples were analyzed .for nitrate, ammonium, and total Kjeldahl nitrogen, orthophosphate and total phosphorus, bicarbonate alkalinity, pH, and specific conductance. Clear differences in streamflow characteristics were noted between the treated and the control watersheds. More surface runoff was observed in the treated watersheds than in the control, suggesting that increased surface runoff may have resulted from the cropping activity. All three watersheds exceeded the phosphorus criterion proposed by the Environmental Protection Agency, and a two-to-threefold increase in total phosphorus concentration was attributed to agricultural land use without employment of conservation practices. A twofold increase in total nitrogen concentration also was noted. Soluble inorganic nitrogen was present at a low concentration in the control watershed, but accounted for 20-30 percent of all nitrogen exported from the treated watersheds. The presence of nitrate nitrogen in the agricultural watersheds was the characteristic most attributable to agricultural activity. The research showed that serious enrichment problems could occur in Piedmont lakes or impoundments if the predominant land use of a watershed were agricultural cropping and if conservation practices were not employed.
- Agricultural use of sewage sludge : a literature reviewKelley, W. D.; Martens, David C.; Reneau, Raymond B.; Simpson, Thomas W. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1984-12)Stricter regulations on discharge of sewage into waters, higher costs of alternate disposal procedures, and higher prices of chemical fertilizers have increased interest in the use of sewage sludge in crop production. This review addresses the benefits and risks of agricultural use of sewage sludge. Topics evaluated in this study are the biological, chemical, and physical aspects of sewage sludge relating to trace elements, pathogens, nitrogen, and phosphorus and also the economic aspects of land application of sewage sludge. For each topic, additional research needs are identified.
- Altered hydrology of the Missouri River and its effects on floodplain forest ecosystemsJohnson, W. Carter; Reily, Peggy Weaks, 1953-; Andrews, L. Scott; McLellan, James F. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1982)
- Annual report, water resources research activities under public law 88-379, fiscal year 1966(Water Resources Research Center, Virginia Polytechnic Institute, 1966)
- Annual report, water resources research activities under public law 88-379, fiscal year 1968(Water Resources Research Center, Virginia Polytechnic Institute, 1968)
- Annual report, water resources research activities under public law 88-379, fiscal year 1969(Water Resources Research Center, Virginia Polytechnic Institute, 1969)
- Aquatic fungi in rivers, their distribution and response to pollutantsFarr, David F.; Paterson, Robert A. (Water Resources Research Center, Virginia Polytechnic Institute and State University, 1974)Two lotic habitats in the vicinity of Blacksburg, Virginia were selected for field investigations. The New River represented a river with a high nutrient load. Little Stony Creek, a tributary of the New River, has no sources of man-made effluent which might contribute nutrients to the stream. Collecting sites on the New River were located above, just below, and some distance farther downstream from the effluent outfall of a munitions plant. The effect of this effluent on the number of taxa was not conspicuous. However, there was a reduction in the number of taxa per collection at the station near the effluent when compared with the other stations. Filamentous aquatic Phycomycetes such as Achlya, Sapro/egnia, and Pythium were commonly found in both habitats. However, a greater diversity of the chytrid type of aquatic Phycomycete was found in Little Stony Creek as compared to the New River. Twelve chytrid taxa were found in Little Stony Creek and two in the New River. Two fungi, Achlya caroliniana from the New River and Rhizidium sp. from Little Stony Creek, were studied in pure culture in terms of the effect of common pollutants on their growth and reproduction. The A. caroliniana had higher tolerances to zinc, cyanide, and mannitol as compared to the Rhizidium sp. The Rhizidium was more tolerant to higher concentrations of detergents than the Achlya.
- Aquatic invertebrate recovery in the Clinch River following hazardous spills and floodsCrossman, John S.; Cairns, John Jr.; Kaesler, Roger L. (Water Resources Research Center, Virginia Polytechnic Institute and State University, 1973)
- Assessing the feasibility and potential expansion of large-scale riparian irrigation in VirginiaTaylor, Daniel B.; Ross, Burton Blake; Vellidis, G.; Lanier, Alan B. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1985-09)The purpose of this study was to develop a method, using readily available information, for evaluating the feasibility of t he expansion of large scale riparian based irrigation. This report represents the first in a series of reports addressing this issue. Its primary purpose is to document the methods which were employed in the feasibility analysis. Microcomputer irrigation system design models were developed to calculate the annual costs of installing and operating center pivot, traveling gun, big gun, and portable pipe irrigation systems. The information generated by these design models was summarized by estimating a series of equations using ordinary least squares regression techniques. These equations can be employed by planners and policy makers in Virginia to evaluate the potential of future conflicts in riparian water use arising from irrigation. An example using the equations in a benefit-cost analysis was presented for Havover County where it borders the Pamunkey River. It was recommended that this procedure be further refined to increase its flexibility , that data bases be developed for the areas of potential riparian based irrigation, and that the entire evaluation procedure be computerized and made more user friendly to facilitate its use by water use policy makers and planners.
- An assessment of the transferability of habitat suitability criteria for smallmouth bassGroshens, Thomas P.; Orth, Donald J. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1993-06)
- Availability and distribution of heavy metals, nitrogen, and phosphorus from sewage sludge in the plant-soil-water continuumRappaport, Bruce D.; Scott, James D.; Martens, David C.; Reneau, Raymond B.; Simpson, Thomas W. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1987)Research was conducted during 1984 and 1985 to determine Cd, Cu, N, Ni, P, and Zn availabilities to barley (Hordeum vulgare L.) and corn (lea mays L.) grown on four sludge-amended soils. Field studies were conducted on Acredale silt loam (Typic Ochraqualf), Bojac loamy sand (Typic Hapludult), Davidson clay loam (Rhodie Paleudult), and Groseclose silt loam (Typic Hapludult). An aerobically digested sewage sludge, which was dewatered for approximately 2 years on sandbeds, was obtained from a sewage treatment plant with major industrial inputs. In the spring of 1984, this sludge was applied at rates of 0, 42, and 84 dry Mg ha- 1 to the poorly drained Acredale soil and at rates of 0, 42, 84, 126, 168, and 210 dry Mg ha - 1 to the well-drained Bojac, Davidson, and Groseclose soils. The 210 dry Mg ha-1 sludge rate supplied 4.5 kg Cd, 750 kg Cu, 3350 kg N, 43 kg Ni, 6900 kg P, and 600 kg Zn ha - 1. A 14-day anaerobic N incubation study indicated that mineralization of sludge organic N varied from 9.2% at the 42 Mg ha - 1 sludge rate to 4.2% at the 210 Mg ha - 1 rate. Th is relatively low percentage of N mineralized from the sludge may reflect the inhibitory effects of the high sludge metal levels on N transformations and the changes in sludge composition during long-term dewatering on sandbeds. Sludge application increased crop yields, except where the amounts of N mineralized from the sludge was inadequate to supply the N requirement of the crop. Crop yields were not decreased by either metal phytotoxicity or P deficiency on the four sludge-amended soils. On the three well-drained soils, Cu and Zn phytotoxicity did not occur where these metals were applied in excess of US EPA guidelines of 280 kg Cu and 560 kg Zn ha- 1. Although there were increases in Cd, Cu, Ni, and Zn in plants grown on the sludge-amended soils, the metal concentrations were within the ranges of those reported for nonsludged soils. Levels of DTPA-extractable metals in the Ap horizon of the soils provided a good indication of the amounts of metals in the soils from sludge application. Relatively low correlations occurred between DTPA-extractable Cd, Cu, Ni, and Zn and the respective metal concentrations in plant tissue. These low correlations were attributed to the small increases in metal concentrations in tissue from metals supplied by sludge application. The DTPA-extractable Cd, Cu, Ni, and Zn concentrations in soils sampled from various depths indicated no downward movement of these metals in the sludge-amended soils, except for virtually negligible downward movement of Cu in the Groseclose soil. Dilute double-acid extractable P in these samples indicated a small amount of P movement in only the sludge-amended Bojac and Davidson soils. The limited N mineralization of the sludge under study substantially reduced the potential for NQ3- contamination of groundwater.
- Benzimidazole fungitoxicants in Virginia soils : movement, disappearance, and effect on microorganismsJanutolo, Delano Blake, 1952- (Water Resources Research Center, Virginia Polytechnic Institute and State University, 1978)
- Biodegradability of atrazine, cyanazine, and dicamba in wetland soilsGu, Ji-Dong; Berry, Duane F.; Taraban, Ronald H.; Martens, David C.; Walker, H. Lynn; Edmonds, William J. (Virginia Water Resources Research Center, Virginia Polytechnic Institute and State University, 1992-02)Small amounts of applied pesticide chemicals eventually can end up in nontarget areas such as wetlands, sediments, and groundwater where anaerobic conditions often predominate. Runoff and leaching are major means by which pesticides move away from application sites. Pesticides also can find their way into nontarget areas as a result of inappropriate disposal and accidental spills. We evaluated the biodegradability of atrazine, cyanazine, and dicamba in wetland soils under nitratereducing and methanogenic conditions. Wetland soil samples were collected from three different sites in the Chesapeake Bay watershed region. These sites represented both tidal (Lawnes and Levy soils) and nontidal (Myatt soil) wetlands. Tidal wetlands are water-saturated throughout the year, whereas nontidal wetlands are saturated only during certain times of the year. Herbicide fate studies were conducted in wetland soil microcosms consisting of serum bottles filled with soil slurry and containing either atrazine, cyanazine, or dicamba. Atrazine was extremely stable in wetland soil microcosms regardless of incubation temperature, redox status (nitrate-reducing versus methanogenic conditions), or soil type. Neither temperature nor redox status affected cyanazine stability in Myatt wetland soil microcosms. We observed a significant decrease in cyanazine concentration in Lawnes wetland microcosms incubated under methanogenic and nitratereducing conditions. Losses were more pronounced at 25° than at 15°C. Results from enrichment culture studies suggest that cyanazine was cometabolized (i.e., cyanazine could not be used as a carbon and energy source by the microorganisms) in Lawnes soil microcosms. Dicamba was readily biodegraded in the wetland soils tested, although total mineralization was not achieved.