Midwest (U.S.A.) reservoir water quality modification I. Particulate parameters

Both qualitative and quantitative approaches were used to evaluate the impact of a flood control, low flow augmentation reservoir on seven water quality parameters: Suspended solids and total phosphate (particulate parameters); BOD, COD, and ammonia (O₂-demanding parameters); and orthophosphate and nitrite plus nitrate N (soluble nutrients). Fourteen years of weekly sampling data above, in, and downstream of the reservoir both before and after the reservoir became operational were analyzed. This paper considers the effects of the reservoir on the particulate parameters. There was a dramatic decrease in both suspended solids and total phosphate concentrations in the reservoir discharges, particularly during periods of high river flows and high reservoir inflow parameter concentrations. At all sampling stations, the annual parameter loading rates (kg ha^?1 yr^?1) correlated linearly with annual runoff (cm yr^?1). The suspended solids removal efficiency of the reservoir was dependent on annual runoff and averaged about 90%. Non-point source contributions of suspended solids were well over 99% when annual runoff exceeded 6.57 cm y^?1 and over 95% even when annual runoff was as low as 1.63 cm yr^?1     

Impact of sanitary landfill on groundwater quality

This paper presents the results of monitoring the shallow groundwater quality around two municipal landfill sites in the Eastern Province of Saudi Arabia. Boreholes were installed at Dhahran and Juaymah sites upstream and downstream of the landfill. Twenty water samples were collected from each borehole and analyzed for various parameters mainly for BOD, COD, TOC, NH₃-N, TKN, sulphate, chloride, hardness and metals. The result of the analysis of water samples from Dhahran boreholes shows an increase in the concentration of pollutants in downstream groundwater over that observed in upstream boreholes. The average concentration of BOD₅, COD and TOC in the samples obtained from the downstream borehole was found to be 6.5, 23.5, and 34.3 mg L^?1, respectively. On the other hand, the mean concentration of the same parameters in upstream monitoring wells was found to be less than 2.4, 11.5, and 10.0 mg L^?1, respectively. The ammonia-N and organic-N in the downstream wells were 0.37 and 0.29 mg L^?1, respectively, whereas, in upstream wells they were 0.11 and 0.15 mg L^?1, respectively. At Juaymah, the average concentration of BOD and TOC in groundwater samples obtained from upstream boreholes were less than 3.0 and 7.2 mg L^?1, respectively, while the concentration of the same parameters in downstream well samples were above 5.0 and 35.0 mg L^?1, respectively. A similar trend of increment of ammonia-N, organic-N, phosphate, sulfate and metals in downstream samples was observed. Since the water from these shallow aquifers at both places is not being used for human consumptions or for any other commercial purpose, therefore, the minor increase in pollutants concentration at downstream level is not of a great concern.     

Electrical Conductivity and Sodium Adsorption Ratio Changes Following Annual Applications of Animal Manure Amendments

Field experiments were conducted to evaluate the effects of repeated annual manure applications on sodium adsorption ratios and electrical conductivity in semi-arid environments. Swine effluent, beef manure, and anhydrous ammonia were annually applied at loading rates of 0, 56, 168, and 504 kg nitrogen (N) ha^?1 to an irrigated, conventionally tilled, continuous corn (Zea mays L.) cropping study in the Oklahoma panhandle. Sodium adsorption ratios increased with swine effluent additions at the high N loading rate application; however, sodium adsorption ratio decreased with the high anhydrous ammonia loading applications and remained unchanged with beef manure applications. Linear correlations were found for swine effluent and anhydrous ammonia applications when N levels increased. Electrical conductivity levels increased 2.35 dS m^?1 with the high anhydrous ammonia loading rate to a level where relative yields for crop production may be at risk of being reduced 50%.     

Application of stabilization pond for purification of textile wastewater in Esfahan,Iran

Two experimental ponds, with an effective volume of 2 m3 each, were constructed in a workshop at the textile plants to investigate the potential for a stabilization pond for purification of textile wastewater. Parametric analysis of pH, temperature, turbidity suspended solids, total suspended solids, DO, BOD, COD, N, and algae was carried out on the influent and the effluent according to the procedures recommended by the standard methods (APHA, 1971). Considering the results obtained from tests after daily observations, the application of an oxidation pond for treatment of textile wastewaters in the winter time was not promising. The ponds had a little activity in aerobic condition. In other seasons the ponds were efficient and the removal of BOD, COD, and N was 81, 78, 72% respectively, with a loading rate of 7.950 g BOD m^?2 day^?1 and detention time of 20 days. The ponds were usually saturated and sometimes super-saturated with dissolved O₂. The experimental ponds were put to work in series for BOD, COD, and N removal observation. The removal did not improve compared with a single pond and algae concentration was noticeably reduced in the effluent.     

Microfauna Community as an Indicator of Effluent Quality and Operational Parameters in an Activated Sludge System for Treating Piggery Wastewater

In order to study the potential use of microfauna as an indicator of effluent quality and operational parameters in an activated sludge system for treating piggery wastewater, an experimental sequencing batch reactor was set up and evaluated by biological and physical–chemical analyses for 12 months. Results show that microfauna (and specifically ciliate protozoa) are a good parameter for assessing effluent quality in terms of both chemical oxygen demand (COD) and ammonia and for assessing the organic and nitrogen load of the system. Specifically, the abundance of ciliates decreases from 20,000 individuals·mL^?1 to ca. 2,500 individuals·mL^?1 and from ca. 10,000 individuals mL^?1 to ca. 200 individuals mL^?1 when effluent concentration is between 550 and 750 mg L^?1 and above 100 mg L^?1 to the COD and ammonia concentrations, respectively. Furthermore, microfauna abundance is reduced from ca. 18,000 individuals mL^?1 (organic load between 0.1 and 0.2 mg COD mg total suspended solids (TSS)^?1 day^?1) to ca. 500 individuals mL^?1 (organic load between 0.3 and 04 mg COD mg TSS^?1 day^?1). Microfauna abundance also decreases as nitrogen loading increases. Nitrogen loading in the range of 5–60 mg NH₄–N g TSS^?1 day^?1 does not have any significant effect on microfauna abundance. However, ammonia loading from 60 to 120 mg NH₄–N g TSS^?1 day^?1 reduces microfauna abundance ca. 6-fold. Ciliate protozoa were the largest microfauna group during the whole period of study, representing ca. 75% of the total microfauna abundance. The largest group in the ciliate community was that of the free-swimming ciliates. This was followed by the group of attached and crawling ciliates. Specifically, the dominant ciliate species during the whole study period were Uronema nigricans, Vorticella microstoma-complex, Epistylis coronata, and Acineria uncinata.     

Anaerobic treatment of potato-processing wastewater by a UASBR-UAF system at low organic loadings

Laboratory-scale models consisting of a simple upflow anaerobic sludge blanket reactor (UASBR) and an upflow anaerobic filter (UAF) in series were subjected to organic loadings of 0.19 to 0.55 kg COD m^?3 d^?1 at 20°C. COD and SS removals were 95 to 98% and 98 to 99%, respectively. Biogas produced by the system amounted to 0.31 to 0.32 m³ CH₄ kg^?1 COD removed. The UASBR was more stable than the UAF in performance. No sign of deterioration in final effluent quality was observed during 420 days of operation under low loading.     

Chemical composition of effluent from high density culture of channel catfish

Production rates of metabolic wastes by channel catfish (Ictalurus punctutas) were estimated by analyzing effluents from high density culture of 940 g and 60 g catfish. Results were integrated over a 24 h steady-state period in which normal feeding activities were maintained and were expressed as g day^?1kg^?1 fish and g day^?1 kg^?1 feed consumed. When expressed on a unit fish weight basis, production rates were greater for 60 g than for 940 g catfish. However, when expressed on a feed consumption basis, production rates of most catabolic products were approximately equal for both size fish. Average values (g day^?1 kg^?1 feed) were as follows: total N, 67; ammonia N, 20; nitrate-nitrite N, 20; 5-day BOD, 98; total solids, 180; total P, 15; total K, 18. Filtered solids from effluent contained 5% nitrogen, 1.6% phosphorus and .13%. potassium. Diurnal variation in production rates were noted with solid production reaching a maximum after each feeding and BOD, NH₃ and nitrate reaching a maximum only in the afternoon.     

Waste loadings from two freshwater Atlantic Salmon Juvenile farms in Scotland

Studies of waste generation from the freshwater phase of Atlantic salmon (Salmo salar L.) production have not been substantially updated since the mid 1980's, and advances in husbandry prectices designed to reduce wastage which have taken place in that period therefore remain unconsidered. In order to determine if reductions have been achieved, two Scottish fish farms were visited on a number of occasions during one year, and outputs of suspended solids (SS), biochemical oxygen demand (BOD), total ammonia nitrogen (TAN) (NH₃+NH₄ ⁺), dissolved reactive and total phosphorus (DRP, TP) were monitored. The range of waste loadings obtained were 9.1–10.0 kg TP t fish^?2 yr^?1, 410 kg BOD₅ t fish^?1 yr^?1, 191–606 kg SS t fish^?1 y^?1, and 20.3–39.3 kg TAN-N t fish^?1 yr^?1. Compared to existing data, a greater range of daily waste loadings were observed, suggesting that more frequent monitoring is required to reduce variations observed in the data set, and to obtain accurate information on waste outputs from such operations. Modifications of feeding methods remains a route through which further reductions in waste outputs may be made.     

Trace element loading of southern Lake Michigan by dry deposition of atmospheric aerosol

Aerosol samples and meteorological data were collected at a mid-southern Lake Michigan site (87° 00′ W, 42° 00′ N) from May through September 1977. Hi-volume samplers with cellulose fiber filters and a digital meteorological data recording system were operated on board the U.S. EPA's R/VRoger R. Simons during four intensive sampling periods. Aerosol samples were analyzed by atomic absorption spectroscopy for seventeen trace elements. A diabatic drag coefficient method was used to determine aerosol deposition velocity (v _d ) overlake. A meanv _d of 0.5 cm s^?1 was found for the 0.1v _d to a long-term climatological record, annual dry deposition loadings to the southern basin for nine elements were estimated. For four elements, Fe, Mn, Pb, and Zn, dry deposition loadings to the southern basin alone of at least 500, 30, 250, and 100 (×10³ kg yr^?1) were found. For Fe and Mn, these loadings represent about 15% of the total of all inputs to Lake Michigan. for Zn and Pb, about one-third to one-half of the annual loading from all sources is from dry deposition of atmospheric aerosol.     

Carbon sequestration in Norway spruce in south Sweden as influenced by air pollution,water availability,and fertilization

Carbon sequestration in 30 yr old Norway spruce in south Sweden following manipulation of nutrient and water availability is presented. The site has an annual precipitation of 1100 mm and a deposition of about 20 kg N and 25 kg S per ha^?1 yr^?1. The soil type is a poorly developed podzol. Treatment include irrigation; artificial drought; ammonium sulphate addition; nitrogen-free-fertilization and irrigation with liquid fertilizers including a complete set of nutrients. The experiment has a randomized block design with four replicates per treatment. A comprehensive investigation of the above ground C storage on an areal basis was made at the start of the experiment and after 3 yr of treatment. After 3 yr of treatment with simulated N-S deposition using ammonium sulphate (100 kg N, 114 kg S ha^?1 yr^?1), C accumulation rates in the above ground compartments had increased by 37%. Similarly, irrigation caused increased C accumulation rates by 25%, whereas simulated drought during the vegetation period during 2 yr followed by 1 yr of recovery caused a 15% reduction of the C accumulation rates. Irrigation combined with liquid fertilization (100 kg N ha^?1 yr^?1), including all important nutrient elements, led to 65% increase in C accumulation rates compared to the control. The C sequestration of the latter treatment gradually increased and, during yr 5 of treatment, 8.6 Mg C ha^?1 accumulated in stems and branches, compared to 3.6 Mg ha^?1 for the control. It is concluded that there is a strong interaction between N-deposition and C accumulation rates in Norway spruce in south Sweden. The C accumulation rates are also sensitive to water availability. The study indicates a great potential to cultivate Norway spruce in south Sweden as a renewable energy source. A shift in energy source from fossil fuels to renewable energy sources will directly reduce the net emissions of CO₂ to the atmosphere.     

Biological treatment of pharmaceutical wastewater

A study of physicochemical and biological treatment of pharmaceutical wastewater by the activated sludge process was performed in an oxidation ditch. The physicochemical study using different coagulants revealed that all the coagulants used are not effective and their doses required were very high for COD reduction. In the biological oxidation study, it was found that the wastewater could be processed at all organic loadings and phenol concentrations encountered in wastewater. The yield coefficient and decay coefficient were 0.75 (COD basis) and 0.01 day^?1 (COD basis), respectively.     

Atmospheric input of trace metals to Lake Michigan

Atmospheric bulk deposition was collected on a monthly basis in the Lake Michigan basin from September 1975 through December 1976 to determine the atmospheric loading of trace elements to Lake Michigan. The sampling network consisted of bulk collectors located at 21 locations in the northern and southern basin. Atmospheric loading rates to Lake Michigan were estimated as (in units of 10⁵ kg yr^?1): Al-50; Fe-28; Mn-6.4; Zn-11; Cu-1.2; Pb-6.4; Cd-0.11; Co- <0.25; Ca-798; Mg-155; Na-110; K-64. Atmospheric deposition of all elements measured was greater in the southern basin than in the northern basin as a result of intense urban/industrial activity in the former. The percentage of total atmospheric deposition falling in the southern basin was: Fe-74%, Al-71%; Mn-75%; Zn-67%; Cu-62%; Pb-78%; Cd-74%; Co- ti 56%; Ca-79%; Mg-62%; Na-65%; K-61 %. Atmospheric loading rates reported are in general agreement with estimates made by others from emission inventories and aerosol concentrations. Atmospheric loadings were estimated to represent 10% or more of the total loadings to Lake Michigan from tributary and erosion sources for the trace elements Mn, Zn, Cu, Cd and Pb. Also, atmospheric deposition may account for recent accumulations of Zn, Cu, Cd, Pb and Co in southern Lake Michigan surficial sediments. The atmospheric Ph flux to southern Lake Michigan was estimated as ～1.7 μg sm^?2 yr^?1 for 1975–1976 which compares favorably with the 1972 anthropogenic Pb flux of 1.3 μg cm^?2 yr^?1 (total ? ～1.5 μg cm^?2 yr^?1) as determined from Pb-210 dating (Edgington and Robbins, 1976). The geographical distribution of trace element loading implicates the southern periphery of Lake Michigan as the principal emission source area.     

Innovative Technology of COD and BOD Reduction from Coffee Processing Wastewater Using Avocado Seed Carbon (ASC)

The study estimated the efficiency of Avocado seed carbon (ASC) for chemical oxygen demand (COD) and biochemical oxygen demand (BOD) reduction from coffee processing wastewater. It was performed under batch mode conditions to investigate the optimum operating conditions and efficiency for COD and BOD reduction with ASC compared with commercial activated carbon (CAC). Adsorption isotherm study was also performed and it was found that the values of regression coefficient (r ²), adsorption capacity (k), and adsorption intensity (1/n) for COD and BOD reduction with ASC were comparable to those of CAC. Under optimum operating conditions, the maximum percentage reduction of COD and BOD concentration using ASC was 98.28% and 99.19%, respectively and with CAC was 99.12% and 99.45%, respectively and hence adsorption capacity of ASC is comparable with that of CAC. Thus, this technique may be a good option for treatment of domestic wastewater.     

Aerobic Biological Treatment of Chestnut Processing Wastewater

Chestnut agro-industrial companies consume a high volume of water for washing and processing fruit, generating a large volume of wastewater. This work studied the biodegradation of chestnut processing wastewater through aerobic assays, varying substrate, and biomass concentrations. In general, this wastewater presents a good biodegradability, especially in experiments with relatively low chemical oxygen demand (COD) (0.4 and 0.6?g O₂ L^?1) allowing a COD removal of 85?C90?%. The best results were obtained in the reactor initially loaded with 2?g?L^?1 of biomass and 0.4 or 0.6?g O₂ L^?1 of COD. These experiments also showed high COD removal rates: 4.25 and 3.88?g COD g^?1 volatile suspended solids (VSS) h^?1, respectively. The sedimentation rate, evaluated for different initial values of biomass (1, 2, and 3?g?L^?1), always presented higher values in the experiments with 2 and 3?g?L^?1 of biomass, regardless of the initial COD value used. After comparing different kinetic models (Monod, Contois, and Haldane), it was observed that the Haldane inhibition model satisfactorily describes the COD biodegradation. AQUASIM software allowed calculating the kinetic constant ranges: K _s, 1.59?C6.99?g COD L^?1; ?? _max, 25?C40?g COD g^?1 VSS day^?1; and K _i values, 0.07?C0.11. These kinetic constants corresponds to maximum rates (??*) between 1.48 and 4.25?g COD g^?1 VSS day^?1 for substrate concentrations (S*) from 0.38 to 0.88?g COD L^?1.     

The Impact of Rainfall on Flows and Loadings at Georgia’s Wastewater Treatment Plants

An assessment of influent and effluent data from 24 wastewater treatment plants (WWTPs) in the state of Georgia with design capacities of 37,850 m³/d (10-mgd) or greater was undertaken. Twelve months of operating data from the 2003 calendar year were evaluated. The objectives of the study were to determine the effect of rainfall intensity on the volumetric flow rate to each WWTP and to determine the relationship between flow rate and the influent five-day, biochemical oxygen demand (BOD₅) and total suspended solids (TSS) concentrations. The relationships between rainfall intensity and influent BOD concentration, rainfall intensity and influent TSS concentration, influent BOD loading and effluent BOD concentration, and influent TSS loading and effluent TSS concentration were also evaluated. Moderate to strong correlations were observed between rainfall intensity and volumetric flow rate, volumetric flow rate and influent BOD and TSS concentrations, average monthly rainfall intensity and influent BOD and TSS concentrations, and between influent BOD and TSS loadings and effluent BOD and TSS concentrations. Weak correlations were observed for some of the relationships when applied to the complete data set however, stronger correlations were achieved by performing statistical analyses of variance and pooling subsets of the data. Peaking factors for flows and loadings were similar to those reported in the literature.     

Mercury evolution (1978–1988) in fishes of the La Grande hydroelectric complex,Quebec, Canada

From 1978 to 1988, the evolution of the Hg content of fish has been monitored in the areas affected by the La Grande hydroelectric complex. Four fish species were considered: two non piscivorous, lake whitefish (Coregonus clupeaformis) and longnose sucker (Catostomus catostomus), and two piscivorous, northern pike (Esox lucius) and walleye (Stizostedion vitreum). The evolution of Hg concentrations in time depends upon fish species and type of reservoirs. Non piscivorous fish react more rapidly than piscivorous. Five years after filling, their Hg level had increased by a factor of four in reservoirs with rapid filling and short renewal rate; levels decreased thereafter. In the La Grande 2 reservoir, the Hg concentration of 400 mm lake whitefish went from 0.16 mg kg⁻¹ before impoundment to 0.57 mg kg⁻¹ 5 yr after filling, and then started to decrease. For 700 mm northern pike, the Hg level went from 0.61 mg kg⁻¹ to 2.99 mg kg⁻¹ and was still increasing 9 yr after initial filling. In reservoirs where filling spans over a few years or with long renewal rate, their Hg content evolves more slowly. In river sections located downstream from reservoirs, the Hg content of non piscivorous species was significantly higher than in reservoirs. In 1988, whitefish exhibited values of 1.22 mg kg⁻¹ in the tailwater of the La Grande 2 power station, compared to 0.48 mg kg⁻¹ in the forebay. This phenomenon could be related to the drift of food organisms from the upstream reservoir. A study of several reservoirs of the Canadian Shield, which were created between 6 and 67 yr ago suggests that it could take between 20 and 30 yr before Hg concentration in fish return to preimpoundment levels.     

Effects of Nitrogen Deposition on Nitrous Oxide Emissions from the Forest Floor

Increasing nitrogen deposition due to human activity might have a serious impact on ecosystem functions such as the nitrogen transformations conducted by microbes. We therefore focused on nitrous oxide (N₂O) production as an indicator of soil microbial activity. The rates of N₂O emission from the forest floor were measured every two weeks in two forest stands in the central part of Japan: a red pine stand at Kannondai and a deciduous stand at Yasato. Nitrogen deposition rates by throughfall were 30.6 kg N ha^?1 y^?1 at Kannondai and 15.7 at Yasato. The rates of N₂O emission ranged from 0.5 to 14.2 µg N m^?2 h^?1 (mean 4.5) at Kannondai and from 0.2 to 7.0 µg N m^?2 h^?1 (mean 2.3) at Yasato. The N₂O emission rate showed significant positive relationships with soil temperature and nitrogen deposition during the preceding two weeks. The annual emission rates of N₂O were 0.38 kg N ha^?1 y^?1 at Kannondai and 0.20 at Yasato. As a the annual nitrogen deposition, these rates were 1.23% at Kannondai and 1.27% at Yasato.     

Assessment of Biogas use as an Energy Source from Anaerobic Digestion of Brewery Wastewater

Energy recovery from a crossflow ultrafiltration (UF) membraneunit employed in order to improve the performance of an anaerobic contact digester for the treatment of brewery wastewater was assessed. The performance of the pilot-scale anaerobic UF membrane system was studied for over 15 months. At steady-state conditions, an organic loading rate of 28.5 kg COD m^-3 d^-1, a hydraulic retention time of 4.2 days and overall COD and BOD removal efficiencies of 99% and almost 100% were achieved, respectively. Percent methane in biogas was found to be in a range of 67–79% with the corresponding methane yield of 0.28–0.35 m³ CH₄ kg^-1 COD_removed. The potential energy recovery from the system treating brewery wastewater at an OLR of 28.5 kg COD m^-3 d^-1 was 87 MJ d^-1 which would enable to maintain all energy requirements of the feed pump, mixing and heating of the reactor contents. In addition to this, 71% of the energy requirement for recirculating the reactor content through the membranes would also be recovered.     

Effect of Flow Rate, Concentration and Transient—State Operations on the Performance of a Biofilter Treating Xylene Vapors

Biological treatment systems such as biofilters offer a potential alternative to the existing physicochemical techniques for the removal of volatile organic compounds from gaseous emissions. In this experimental work, continuous phase biofiltration of xylene vapors were performed in a laboratory scale compost biofilter that was inoculated with a xylene-acclimatized consortium. The performance was assessed by continuously monitoring the removal efficiency (RE) and elimination capacity (EC) of the biofilter at loading rates varying between 2–220 g?m^?3?h^?1. The steady-state removal efficiencies were maintained between 60% and 90% up to a loading rate of 80 g?m^?3?h^?1. The removal efficiency decreased significantly at loading rates higher than 100 g?m^?3?h^?1. The pressure drop values were consistently less and insignificant in affecting the performance of the system. The present study also focuses in evaluating the stability of biofilter during shut down, restart, and shock-loading operations. An immediate restoration of biological activity after few days of starvation indicated their capability to handle discontinuous treatment situations which is more common to industrial biofilters. The sensitiveness of the biofilm to withstand shock loads was tested by abruptly increasing/decreasing the loading rates between 9–55 g?m^?3?h^?1, where, removal efficiencies between 60–90% were achieved. These results prove the resilience of the biomass and the stability of the compost biofilter. Anew, results from kinetic analysis reveal that, steady-state xylene removal in the biofilter can be adequately represented by Michaelis–Menten type kinetics, and the kinetic constants namely, EC_max (120.4 g?m^?3?h^?1) and K _s (2.21 g?m^?3) were obtained.     

A chloride budget for Onondaga Lake,New York,U.S.A.

A Cl budget is presented for a 12 yr period (1970–1981) for Cl enriched (approximate volume-weighted average concentration of 1500 mg Cl L^?1) Onondaga Lake, New York. The budget utilizes continuous discharge and lake and stream water chemistry data, collected at an interval of approximately 2 weeks, over the 12 yr study period. Budget calculations are supplemented by high frequency water chemistry data from the lake and the tributary carrying the major portion of the loading. More than 85% of the external load of Cl (approximately 9 × 10⁸ kg yr^?1) to the lake originates from an alkali manufacturer. Export of Cl from the lake was highly correlated to outflow from the lake (R = 0.915, for a resolution of 1 mo). A good balance between estimated external loads and lake export was obtained (within 7%) for the 12 yr period, indicating that lake concentrations are consistent with external loading of this conservative substance. The results of this analysis contradict previous calculations that indicated 40 to 50% of the Cl in the lake originated from natural internal sources.