Notes From The National Air Quality Conference

The National Air Quality Conference, which was held during January 14-16 in San Francisco, promised to “provide decision-makers in government, business, and labor with information on the possible economic and employment impacts of the federal Clean Air Act along with strategies for change.” The meeting appeared to be important from the standpoint of who was speaking, who was attending, and who was reacting. JAPCA asked Francis J. O’Donnell, editor of Air/Water Pollution Report, to provide this special report.     

Freshwater Wetland dynamics in South Kingstown,Rhode Island, 1939–1972

The extent and causes of changes in the fresh-water wetlands of South Kingstown, Rhode Island were determined through field work and through the analysis of panchromatic aerial photographs taken in 1939 and 1972. During this period, there was a net loss of 0.9 percent of the total area (2345.2 ha) of wetland present in 1939. Highway construction and residential development accounted for most of this loss. Approximately 17 percent of the wetland present in 1939 had changed sufficiently by 1972 to warrant reclassification. Plant succession alone accounted for 57 percent of the changes in wetland types, while man's activities were influential in 41 percent of the cases. Ninety-two percent of the natural changes in wetland types was progressive, while 58 percent of the changes induced by man and undetermined causes was retrogressive. Man's major role was to alter the water regimes and vegetation of wetlands. There was a decrease in wetland diversity as the most abundant type, wooded swamp, grew in area while the abundance of shallow marshes, meadows, and shrub swamps declined. A knowledge of wetland dynamics is essential in the management of wetlands for a diversity of wildlife and other natural values.     

In-Situ Phytoremediation of Pahs Contaminated Soils Following a Bioremediation Treatment

Phytoremediation of pollutants in soils is an emerging technology, using different soil-plant interaction properties. For organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), phytodegradation seems to be the most promising approach. It occurs mostly through an increase of the microbial activity in the plant rhizosphere, allowing the degradation of organic substances, a source of carbon for soil microbes. Despite a large amount of available data in the literature concerning laboratory and short term PAH phytodegradation experiments, no actual field application of such technique was previously carried out. In the present study, a soil from a former coking plant was used to evaluate the feasibility and the efficiency of PAH phytodegradation in the field during a three years trial and following a bioremediation treatment. Before the phytoremediation treatment, the soil was homogenized and split into six independent plots with no hydrological connections. On four of these plots, different types of common plant species were sowed: mixture of herbaceous species, short cut (P1), long cut (P2), ornamental plants (P3) and trees (P4). Natural vegetation was allowed to grow on the fifth plot (P5), and the last plot was weeded (P6). Each year, representative sampling of two soil horizons (0–50 and 50–100 cm) was carried out in each plot to characterize the evolution of PAHs concentration in soils and in soils solution obtained by lixiviation. Possible impact of the phytoremediation technique on ecosystems was evaluated using different eco- and genotoxicity tests both on the soil solid matrix and on the soil solution. For each soil horizon, comparable decrease of soil total PAHs concentrations were obtained for three plots, reaching a maximum value of 26% of the initial PAHs concentration. The decrease mostly concerned the 3 rings PAHs. The overall low decrease in PAHs content was linked to a drastic decrease in PAHs availability likely due to the bioremediation treatment. However, soil solutions concentration showed low values and no signficant toxicity was characterized. The mixture of the herbaceous species seemed to be the most promising plants to be used in such procedure.     

Interstate Air Pollution Study—St. Louis Area Air Pollutant Emissions Related to Actual Land Use

The Interstate Air Pollution Study of the St. Louis-East St. Louis Metropolitan Area, conducted in 1963–1964, provided data for this report of air pollutant emissions related to three land-use categories: (1) residential, (2) institutional and commercial, and (3) industrial. A fourth land-use category, transportation and open space, is included in some calculations. The sources of pollutants considered are: (1) power generation, both electric utilities and industrial, (2) fuels used for space heating, (3) solid waste disposal, and (4) industrial processes. The pollutant emissions considered are particulates and sulfur oxides. Cumulative frequency distributions given are based on acres of land use and corresponding emissions per unit area. These frequency distributions—actual emission conditions that can be related to known air quality levels—provide a basis for performance standards and a guide for planners and others in future city developments, not only in St. Louis but in other similar cities as well. A suggested method for determining a different type performance zoning standard is presented. This standard is based on average conditions and thus would supplement, not replace, standards based on maximum allowable emissions. Calculations for such standards relating to St. Louis are presented.     

Drought Resilience of the California Central Valley Surface‐Ground‐Water‐Conveyance System1

Abstract: A series of drought simulations were performed for the California Central Valley using computer applications developed by the California Department of Water Resources and historical datasets representing a range of droughts from mild to severe for time periods lasting up to 60 years. Land use, agricultural cropping patterns, and water demand were held fixed at the 2003 level and water supply was decreased by amounts ranging between 25 and 50%, representing light to severe drought types. Impacts were examined for four hydrologic subbasins, the Sacramento Basin, the San Joaquin Basin, the Tulare Basin, and the Eastside Drainage. Results suggest the greatest impacts are in the San Joaquin and Tulare Basins, regions that are heavily irrigated and are presently overdrafted in most years. Regional surface water diversions decrease by as much as 70%. Stream‐to‐aquifer flows and aquifer storage declines were proportional to drought severity. Most significant was the decline in ground water head for the severe drought cases, where results suggest that under these scenarios the water table is unlikely to recover within the 30‐year model‐simulated future. However, the overall response to such droughts is not as severe as anticipated and the Sacramento Basin may act as ground‐water insurance to sustain California during extended dry periods.     

Interactions of uranium with polyphosphate

Inorganic polyphosphates (PolyP) are simple linear phosphate (PO(4)(3-)) polymers which are produced by a variety of microorganisms. One of their functions is to complex metals resulting in their precipitation. We investigated the interaction of phosphate and low-molecular-weight PolyP (1400-1900Da) with uranyl ion at various pHs. Potentiometric titration of uranyl ion in the presence of phosphate showed two sharp inflection points at pHs 4 and 8 due to uranium hydrolysis reaction and interaction with phosphate. Titration of uranyl ion and PolyP revealed a broad inflection point starting at pH 4 indicating that complexation of U-PolyP occurs over a wide range of pHs with no uranium hydrolysis. EXAFS analysis of the U-HPO(4) complex revealed that an insoluble uranyl phosphate species was formed below pH 6; at higher pH (> or = 8) uranium formed a precipitate consisting of hydroxophosphato species. In contrast, adding uranyl ion to PolyP resulted in formation of U-PolyP complex over the entire pH range studied. At low pH (< or = 6) an insoluble U-PolyP complex having a monodentate coordination of phosphate with uranium was observed. Above pH 6 however, a soluble bidentate complex with phosphate and uranium was predominant. These results show that the complexation and solubility of uranium with PO(4) and PolyP are dependent upon pH.     

Worker policing and worker reproduction in Apis cerana

Workers of the Asian hive bee, Apis cerana, are shown to have relatively high rates of worker ovary activation. In colonies with an active queen and brood nest, 1-5% of workers have eggs in their ovarioles. When A. cerana colonies are dequeened, workers rapidly activate their ovaries. After 4 days 15% have activated ovaries and after 6 days, 40%. A cerana police worker-laid eggs in the same way that A. florea and A. mellifera do, but are perhaps slightly more tolerant of worker-laid eggs than the other species. Nevertheless, no worker's sons were detected in a sample of 652 pupal males sampled from 4 queenright colonies. A cerana continue to police worker-laid eggs, even after worker oviposition has commenced in a queenless colony.     

Development and Demonstration of an Explicit Lumped-Parameter Biofilter Model and Design Equation Incorporating Monod Kinetics

Abstract

Biofiltration is an economical air pollution control (APC) technology, particularly suitable for the treatment of air-streams having high flow rates and low concentrations of volatile organic compounds (VOCs). This technology utilizes enzymatic catalysis at ambient conditions to mineralize such pollutants to CO₂, H₂O, and salts. A pilot-scale study conducted for more than 4 years investigated the development of a new biofiltration technology employing trickle bed air biofilters (TBABs). Following the completion of this experimental study, additional data analysis was performed to develop a simple lumped-parameter biofilter model, assuming first-order kinetics. This model related the observed biofilter performance to the principle independent physical, thermodynamic, and biochemical parameters. The initial model has subsequently been expanded to incorporate Monod kinetics. In this paper, the development and use of the final explicit lumped-parameter biofilter model and design equation, incorporating Monod kinetics, are presented. To facilitate the application of this model, practical procedures are also presented for the determination of VOC solubility, VOC biokinetic Monod parameters, and the maximum practical biofilter inlet VOC concentration.     

沉淀法处理含铜废水及其沉淀产物的表征

采用Ca(OH)2、Na2 CO3和Na2S作为沉淀剂处理模拟酸性含铜废水.实验结果表明:对铜离子去除率由高至低的顺序为Ca (OH)2＞Na2CO3＞Na2S;沉淀60 min后,污泥沉降体积由高至低的顺序为Na2CO3＞Ca(OH)2＞Na2S;上清液浊度由高至低的顺序为Ca(OH)2＞Na2CO3＞Na2S.沉淀...