THE INFLUENCE OF SPRING AND FALL TEMPERATURES ON THE AVOIDANCE RESPONSE OF JUVENILE ATLANTIC MENHADEN,BREVOORTIA TYRANNUS,EXPOSED TO SIMULTANEOUS CHLORINE-δT CONDITIONS1

ABSTRACT: The avoidance response of groups of juvenile Atlantic menhaden, Brevoortia tyrannus, was evaluated by exposing test species to a range of simultaneous total residual chlorine (TRC) (0.00, 0.05, 0.10, and 0.15 mg/L) and elevated temperature (0, 2, 4, and 6°C) conditions simulating power plant discharges. This species was tested at both 15 and 20°C to determine possible effects of acclimation temperature on the avoidance response. These temperatures were selected to represent spring or fall thermal conditions when most East Coast power plant facilities initiate power plant chlorination in the spring or terminate the use of this biocide in the fall. An unbalanced 3-factor factorial design was used to develop response surface avoidance models at 15 and 20°C. The model developed at 15°C showed: (1) an increase in avoidance occurred at all δT conditions as TRC increased from 0.00 to 0.05 mg/L; (2) a greater degree of avoidance occured at TRC concentrations above 0.05 mg/L at all δT conditions; and (3) TRC was the most important term inflencing avoidance. The model for Atlantic menhaden at 20°C showed: 1) avoidance increased with increasing TRC concentration at each δT condition; (2) avoidance did not necessarily increase with increasing δT's at each TRC concentration; (3) greatest avoidance occured at 0°C δT and 0.15 mg/L TRC; and (4) TRC was the most important term influencing avoidance. There was a significant difference (p < 0.00001) between avoidance models at 15 and 20°C. However, when extreme conditions of 0.15 mg/L TRC and 0–6°δT were compared, the degree of avoidance responses (percent time in control area) was similar.     

CAGED FISH AS MONITORS OF POLLUTION: EFFECTS OF CHLORINATED EFFLUENT FROM A WASTEWATER TREATMENT PLANT1

ABSTRACT: Fish confined to cages were used to determine the effects of effluent from a wastewater treatment plant (WWTP). Control fish were kept in cages in an aquaculture pond. Acute effects of the effluent entering the final oxidation pond of the WWTP were determined by confining channel catfish (Ictalurus punctatus) at the pond inlet; the mean total residual chlorine (TRC) concentration was 0.9 mg/l during this exposure. After 8 h, 42 percent of the fish had died and survivors had severe lesions of the skin and gills. During the first two weeks of exposure, channel catfish at the outlet of the final oxidation pond (mean TRC=0.1 mg/l) were predisposed to bacterial infection but lost the parasitic trematodes that were on the gills when the fish were placed in cages. After several weeks, exposed fish had histologic lesions, enlarged livers, and reduced growth. The presence of unidentified carcinogen(s) in the effluent of this WWTP was indicated by papillomas developing on caged black bullheads (Ictalurus melas) and hepatic-enzyme induction in channel catfish. In situ exposure of caged fish was advantageous because storage and pretreatment of water samples were not required, and exposure levels corresponded to those present in the environment. The use of cages for containment of fish during field exposure allowed confinement to the location of interest and convenient sampling of the fish. Unlike wild fish, the caged fish could be compared to control fish with the same pre-exposure history.     

FIELD-LABORATORY DETERMINED AVOIDANCES OF THE SPOTFIN SHINER AND THE BLUNTNOSE MINNOW TO CHLORINATED DISCHARGES1

ABSTRACT: The responses of the spotfin shiner (Notropis spilopterus) and bluntnose minnow (Pimephales notatus) to intermittent chlorine discharges from a fossil fuel power plant in the New River were investigated by seine collections in the chlorinated discharge channel, and chlorine avoidances were obtained in a field laboratory at the power plant in Glen Lyn, Virginia. No fish were captured by seine during chlorination periods when the total chlorine (TCR) and free chlorine (FCR) residuals were, respectively, 0.46 and 0.27 mg/1 or higher at river water temperatures of 12 C or less. For collections made between eight-hour chlorination periods, the number of fish was reduced by approximately 50% at 0.20 and 0.06 mg/1 TCR and FCR, respectively. Significant (0.05 level) laboratory avoidances occurred at 0.10 to 0.20 mg/1 TCR (0.03 to 0.14 mg/1 FCR) for both species when exposed to increasing TCR concentrations of 0.10, 0.20, 0.30 and 0.40 mg/1. Responses varied with acclimation temperature (6, 12, 18 and 24 C) with no consisteent trends between species. When exposed to a constant TCR concentration during any one test (0.14, 0.18 and 0.26 mg/1 for the spotfin shiner, and 0.11 and 0.17 mg/1 for the bluntnose minnow), significant avoidances were observed at 0.26 and 0.17 mg/1 for each species, respectively. In all laboratory trials, occurrence or residence times decreased with increasing chlorine concentration, with residence times as high as 64.7% at 0.10 mg/1 TCR and as low as 8.3% at 0.40 mg/1 being observed.     

INACTIVATION OF GIARDIA MURIS CYSTS BY CHLORAMINES1

ABSTRACT: In a study to measure the efficacy of chioramines at inactivating Giardia cysts, the ability of cysts to excyst was measured after exposure to different concentrations of chloramines, for different times, and at different temperatures and pH. The chloramines were generated by mixing ammonium sulfate and sodium hypochlorate in water to approximate a 7:1 chlorine:ammonia ratio by weight. Times of 40, 80, 180, and 270 minutes; temperatures of 3, 10, and 18°C; target chioramine concentrations of 0.4, 1.4, 2.0, and 2.6 mg/L; and pH of 7.0 and 8.5 were the actual values tested. The combinations of these variables that were able to inactivate >99.8 percent of the cysts were a minimum chloramine concentration of 2.26 mg/L applied for 270 minutes at a water temperature of 10°C; and at 18°C, averaged minimum chloramine concentrations of 2.14 and 1.55 mg/L applied for 180 and 270 minutes, respectively. The minimum CT values corresponding to these combinations capable of >99.8 percent cyst inactivation, are 610 at 10°C and 385 at 18°C. Temperature was noted to exert a major effect on the ability of chloramines to inactivate cysts. Modifications of the methods used to generate chloramines may have an effect on the capacity of this disinfectant to inactivate cysts.     

二氧化氯杀菌处理石化循环冷却水

以硫酸盐还原菌,铁细菌以及异养菌数为指标,研究二氧化氯对石化厂循环冷却水的杀菌效果。考察了二氧化氯投加量,杀菌时间,温度及pH以及余氯量随时间的变化。结果表明,在CLO2投加量为3mg／L、灭菌时间为90min时,出水细菌数即可达到化工行业循环冷却水处理标准,并且余氯可在0．5-1．0mg／L范围内维持2h。温度和pH的改变对杀菌效果影响不大。     

Projected Climate Change Effects on Winterkill in Shallow Lakes in the Northern United States

2 was obtained from the output of the Canadian Climate Center General Circulation Model. To illustrate the effect of projected climate change on lake DO characteristics, we present herein DO information simulated, respectively, with inputs of past climate conditions (1961–1979) and with a projected 2 × CO₂ climate scenario, as well as differences of those values. Specific parameters obtained were minimum under-ice and lake bottom DO concentration in winter, duration of under-ice anoxic conditions (<0.1 mg/liter) and low DO conditions (<3 mg/liter), and percentage of anoxic and low DO lake volumes during the ice cover period. Under current climate conditions winterkill occurs typically in shallow eutrophic lakes of the northern contiguous United States. Climate warming is projected to eliminate winterkill in these lakes. This would be a positive effect of climate warming. Fish species under ice may still experience periods of stress and zero growth due to low DO (<3 mg/liter) conditions under projected climate warming.     

Impingement losses of white perch at Hudson River power plants: Magnitude and biological significance

We performed a quantitative assessment of the impact of impingement at power plants on the Hudson River white perch population We estimated that impingement reduces the abundance of each white perch year class by at least 10% and probably by 15–20% or more after 2–3 years of vulnerability to power plants We attempted to detect effects of impingement on average year-class abundance of white perch from a time series of abundance indices derived from impingement data We found, however, that neither impingement collection rates observed at Hudson River power plants nor beach seine data provide a reliable index of year-class strength in white perch. Even if a reliable index were developed, natural fluctuations in year-class strength are great enough that a short-term monitoring program would be inadequate for detecting even a large reduction in average year-class strength. We performed a multipopulation analysis using simple food chain and food web models The results suggest that any long-term decline in white perch abundance caused by impingement should be accompanied by an increase in the abundance of one or more competing fish species and by an increase in the biomass of adult white perch relative to young-of-the-year.We conclude that 1) at present, assessments of population-level impact of impingement should focus on short-term effects, 2) research is needed to develop a reliable index of year-class strength for use in long-term monitoring programs, 3) identification and quantification of natural environmental factors influencing year-class strength are needed to improve our ability to predict and detect changes in abundance, and 4) it would be useful in designing monitoring programs to focus on detecting patterns of change among populations and age groups rather than solely on declines in abundance of individual populationsResearch sponsored by the Office of Nuclear Regulatory Research, US Nuclear Regulatory Commission under Interagency Agreement No. 40-550-75 with the US Department of Energy under Contract W-7405-eng-26 with Union Carbide Corporation. Publication No. 2030, Environmental Sciences Division, ORNL.     

PERFORMANCE OF A NEW POLYMERIC WATER DISINFECTANT1

ABSTRACT: A new insoluble N-halamine polymeric disinfectant material has been tested in a water filter application to determine (1) its tendencies to leach undesirable decomposition products, (2) its range of potential applicability, and (3) its regenerability. In flowing water tests, poly-1,3-dichloro-5-methyl-5-(4‘-vinylphenyl)hydantoin (Poly-I) leached only small amounts of total organic carbon, free and total chlorine, anions, and volatile organics such as trihalomethanes. Furthermore, Poly-I provided bactericidal efficacy over the pH range 4.5 to 9.5 and at temperatures as high as 37°C. Poly-I is deactivated by reducing agents such as sodium thiosulfate and by ethanol; following deactivation, it can be regenerated by exposure to flowing aqueous free chlorine. Poly-I appears suitable for use as a biocidal filter for small potable and recreational waters, for it is effective over a wide pH and temperature range and is readily regenerable. It would not be useful, however, for disinfection of large bodies of water such as in city treatment plants because of its cost and the large amount of the material that would be necessary.     

Evaporative Cooling of Water in a Small Vessel Under Varying Ambient Humidity

Evaporative cooling of water in a small porous clay vessel was studied under controlled humidity conditions. In steady-state experiments performed at an ambient temperature of 23 °C, the cooling effect increased from 4.7 to 8.3 °C as the ambient relative humidity decreased from 60 to 15%. External heat and mass transfer coefficients, estimated from the steady-state measurements, were used in mathematical models to predict the experimentally observed transient temperature variation of the water under ramp changes of the ambient relative humidity. With a prototypical cool chamber containing water tested in Kolkata, India under an ambient temperature of 34.5–35 °C, the cooling effect reached a maximum of 7 °C between 3 and 3:30 PM and then declined to 4.5 °C around 6 PM.     

DISINFECTION WITH QUATERNARY AMMONIUM COMPOUNDS1

ABSTRACT: The most common disinfection method is chlorination, however, it has been known that the practice of chlorination for water treatment in the Mississippi River area has caused a significant increase in mortality. The objective of this research was to search for effective disinfectants to replace chlorine. Three cationic surfactants have been tested for their bactericidal properties under various conditions. It has been found that 1 mg of cetyldimethyl-benzylammonium chloride can destroy about 4500 coliforms in one liter water within 10 minutes, under neutral pH conditions and room temperature. Cationic quaternary ammonium compound, therefore, can be a potential candidate disinfectant for replacing chlorine when necessary.     

BIOLOGICAL MONITORING OF BLUEGILL ACTIVITY1

ABSTRACT: Bluegills were exposed for one hour to 0.2 or 2.3 mg/liter water soluble fraction (WSF) of JP-4 in a testing chamber designed to contain individual fish. A strain gage paddle was used to monitor activity. Whole body movement of individual fish did not change appreciably during exposure to either 0.2 or 2.3 mg/liter WSF-JP-4. Strength of pectoral fin movement, accounting for the majority of the fish behavior, increased in six of ten individuals exposed to 2.3 mg/liter WSF-JP-4. Pectoral fanning may be a useful parameter to indirectly assess water quality.     

The Control of an Invasive Bivalve, Corbicula fluminea, Using Gas Impermeable Benthic Barriers in a Large Natural Lake

Anoxia can restrict species establishment in aquatic systems and the artificial promotion of these conditions can provide an effective control strategy for invasive molluscs. Low abundances (2-20 m(-2)) of the nonnative bivalve, Asian clam (Corbicula fluminea), were first recorded in Lake Tahoe, CA-NV in 2002 and by 2010 nuisance-level population densities (>10,000 m(-2)) were observed. A non-chemical control method using gas impermeable benthic barriers to reduce dissolved oxygen (DO) concentrations available to C. fluminea was tested in this ultra-oligotrophic natural lake. In 2009, the impact of ethylene propylene diene monomer (EPDM) sheets (9 m(2), n = 6) on C. fluminea beds was tested on 1-7 day intervals over a 56 day period (August-September). At an average water temperature of 18 °C, DO concentrations under these small barriers were reduced to zero after 72 h resulting in 100 % C. fluminea mortality after 28 days. In 2010, a large EPDM barrier (1,950 m(2)) was applied to C. fluminea populations for 120 days (July-November). C. fluminea abundances were reduced over 98 % after barrier removal, and remained significantly reduced (>90 %) 1 year later. Non-target benthic macroinvertebrate abundances were also reduced, with variable taxon-specific recolonization rates. High C. fluminea abundance under anoxic conditions increased the release of ammonium and soluble reactive phosphorus from the sediment substrate; but levels of unionized ammonia were low at 0.004-0.005 mg L(-1). Prolonged exposure to anoxia using benthic barriers can provide an effective short term control strategy for C. fluminea.     

EFFECTS OF PLACER GOLD MINING ON PRIMARY PRODUCTION IN SUBARCTIC STREAMS OF ALASKA1

ABSTRACT: Turbidity, total residues, settleable solids, vertical light extinction, and primary production were measured in mined and unmined streams located in the interior highlands of Alaska. Undisturbed streams had low turbidities (< 1 NTU), total residue concentrations averaging 120 mg 1^?1, and undetectable settleable solids. During active mining, turbidity, total residues, and settleable solids levels in a moderately mined stream averaged 170 NTU, 201 mg 1^?1, and < 0.1 ml 1^?1, respectively. In a heavily mined stream, turbidity and total residues were two orders of magnitude higher than in unmined streams and settleable solids nearly always exceeded 0.2 ml 1^?1. Vertical extinction coefficients and turbidity were positively correlated. In undisturbed streams gross primary productivity (g-O₂m^?2d^?1) ranged from 0.20 shortly after spring breakup to a maximum of 1.20 in early fall. Productivity in the moderately mined stream was reduced by 50 percent while photosynthetic efficiency doubled. Primary production was undetectable in a heavily mined stream. Maximum standing crops of periphyton measured as chlorophyll a occurred in fall in an undisturbed stream after 13 weeks of exposure and ranged from 4.5 to 11.8 mg-chl a m^?2. The highest chlorophyll a densities recorded in the moderately mined stream was 3.8 mg m^?2, and no chlorophyl a was detected in the heavily mined stream.     

Adsorption studies of hazardous malachite green onto treated ginger waste

Adsorption of malachite green (MG) from aqueous solution onto treated ginger waste (TGW) was investigated by batch and column methods. The effect of various factors such as initial dye concentration, contact time, pH and temperature were studied. The maximum adsorption of MG was observed at pH 9. Langmuir and Freundlich isotherms were employed to describe the MG adsorption equilibrium. The monolayer adsorption capacities were found to be 84.03, 163.9 and 188.6 mg/g at 30, 40 and 50 °C, respectively. The values of thermodynamic parameters like ΔG°, ΔH° and ΔS° indicated that adsorption was spontaneous and endothermic in nature. The pseudo second order kinetic model fitted well in correlation to the experimental results. Rechienberg's equation was employed to determine the mechanism of adsorption. The results indicated that film diffusion was a major mode of adsorption. The breakthrough capacities were also investigated.     

Performance of a small-scale solar-powered adsorption cooling system

In this study, an experimental investigation on the performance of a small-scale residential-size solar-driven adsorption (silica gel-water) cooling system that was constructed at Assiut University campus, Egypt is carried out. As Assiut area is considered as hot, arid climate, field tests for performance assessment of the system operation during the summer season are performed under different environmental operating conditions. The system consists of an evacuated tube with a reflective concentration parabolic surface solar-collector field with a total area of 36 m², a silica gel-water adsorption chiller of 8 kW nominal cooling capacity, and hot and cold water thermal storage tanks of 1.8 and 1.2 m³ in volume, respectively. The results of summer season field test show that under daily solar insolation varying from 21 to 27 MJ/m², the solar collectors employed in the system had high and almost constant thermal efficiency. The daily solar-collector efficiency during the period of system operation ranged from about 50% to 78%. The adsorption chiller performance shows that the chiller average daily coefficient of performance (COP) was 0.41 with the average cooling capacity of 4.4 kW when the cooling-water and chilled-water temperatures were about 31°C and 19°C, respectively. As the chiller cooling water is cooled by the cooling tower in the hot arid area, the cooling water is at a higher temperature than the design point of the chiller. Therefore, an experiment was carried out using the city water for cooling. The results show that an enhancement in the chiller COP by 40% and the chilling power by 17% has been achieved when the city water was 27.7°C.     

含油污水回用处理新工艺研究

研究了一种处理回用含油污水的新工艺,二期炼油污水深度处理中试研究表明,以炼油企业二级处理达标排放污水为处理对象,在使用该工艺处理水量为0.5m3/h、水力停留时间为1.49h 以及污水中COD、氨氮、石油类的浓度变化分别为44.07～102.13 mg/L、28.37～50.01 mg/L、4.10～6.77 mg/L时,平均去除率分别达到94%、96.1%、91.9%,其排出水质符合循环水补充水的水质要求。对该工艺进行了5.5h抗冲击实验,结果表明其抗冲击能力优良。     

Production of chicken fat ethyl esters via optomized protocols with dry washing by silica gel

The chicken fat ethyl ester (CFEE) was developed through alkali-catalyzed transesterification with ethanol using potassium hydroxide (KOH) as a catalyst. Parameters affecting the process of transesterification such as the catalyst concentration, ethanol to oil molar ratio, reaction temperature, and reaction duration are investigated. As a result, maximum CFEEs of 90% (~96.21 ester content% w/w) was obtained under optimal conditions of 1.0 wt.% KOH, 8:1 ethanol to fat molar ratio, a reaction temperature of 70°C, and a duration of 90 min. Dry washing method using (3.0% w/w) of silica gel was used to purify the crude ethyl ester from the residual catalyst, glycerol, and other impurities. Properties of the produced ethyl esters were determined and found in accordance with specifications prescribed by the ASTM standards. Moreover, blends of CFEEs and petrodiesel were prepared and evaluated according to ASTM test methods.     

Optimal conditions of Al and Fe extraction from laterite soil using D-optimal design

This paper reports pioneering work in identifying an alternative coagulation agent of wastewater treatment, given the availability of commonly used agents are of a higher cost relative to more natural sources, such as soil. The alternative proposed is laterite soil from northern Malaysia because it contains high amounts of Al and Fe, which are well-known coagulants. The soil was grinded and sieved to obtain uniform particle sizes of <250???m. Al and Fe were extracted from the soil. Extraction agents: (1) HCl, (2) NaOH, and (3) HCl?+?NaCl were chosen. It was found that the most effective agent to extract Fe was 5?N HCl while to extract Al was HCl?+?NaCl, 2 and 4?N, respectively. D-optimal design observed that extraction time t, temperature T, and ratio of amount of laterite soil to amount of extractants r, showed a significant effect on Al extraction. In contrast, the combination of factors t and r exhibited insignificant effect on Fe extraction while other factors were significant. The optimum conditions for extraction of both Al and Fe were 90?°C, 40?min, for r?=?1:15, which gave [Fe]?=?1,870?mg/l and [Al]?=?0.17?mg/l and 90?°C, 90?min, for r?=?1:10, which gave [Fe]?=?2,900?mg/l and [Al]?=?0.130?mg/l. Since concentration of Fe extracted from laterite soil was high, it was concluded that laterite soil can be considered as an alternative and novel source of coagulant applicable in a wastewater treatment coagulation process.     

EFFECT OF THE PAPER INDUSTRY ON WATER QUALITY OF THE LOWER FOX RIVER1

ABSTRACT: The Lower Fox River, Wisconsin, hosts the densest concentration of paper mills in the US., with 18 located along a 4Gde stretch between Lake Winnebago and Green Bay, Lake Michigan. Some of these companies use only primary, others also secondary, waste treatment techniques. Comparison of the quantities of wastes discharged with the legal limits indicates that all plants discharge only 40-50 percent or less of the allowable suspended solids; most discharge < 50 percent of the allowable BOD. This is equal or better than the performance of paper companies elsewhere in the state. Reductions in pollutant discharges have corresponded to improved water quality, though too much BOD is still discharged to be adequately assimilated by the Fox River. The relatively low current level of discharges means permit levels would have to be drastically cut to make any significant impact on water quality. Only a few companies might be seriously affected by such changes. Flow and temperature related permits would likely be more effective, but more difficult to comply with for the industry. Toxic substances are also a potential problem, particularly chlororganic compounds that can form in situ from the chlorine frequently used for pulp bleaching.     

ACUTE RESIDUAL TOXICITY OF SEVERAL DISINFECTANTS IN DOMESTIC AND INDUSTRIAL WASTE WATER1

ABSTRACT: This study determined the acute toxicity of waste water disinfected with chlorine, bromine chloride, or ozone. The residual toxicity of effluent dechlorinated with sulfur dioxide was also tested. Toxicity tests were conducted with cyprinid, salmonid, and centrarchid fishes, as well as several species of fresh water macroinvertebrates. Residual chlorine exhibited the greatest toxicity of the disinfectants tested; dechlorination with sulfur dioxide effectively eliminated the toxicity of chlorinated effluent. Residual ozone produced mortality in test animals only under special conditions where subjects were exposed to effluent immediately after it was contacted with ozone, and chlorobrominated effluent was more toxic to salmonids than chlorinated effluent.