Journal of Environmental Engineering

Asbestos‐containing materials have been used in 20%–50% of the institutions in this country for ceiling, boiler and pipe insulation, acoustical treatment, and fireproofing. Medical criteria indicates that there is no limiting dose relating relationship between asbestos exposures and the various cancers it may cause that are either fatal or difficult to treat. The Environmental Protection Agency estimates that between 100 and 6,800 people may be expected to die prematurely of cancers due to non‐peak asbestos exposure at the prevailing levels in schools. Total environmental health impacts may be considerably higher due to peak exposures created by maintenance, renovation, and other activities. The purpose of this treatise is to present state‐of‐the‐art asbestos environmental health auditing procedures, corrective action program design and implementation, and liability/risk control considerations to reduce the projected environmental health impacts. Special emphasis is placed on the use of decontamination air‐lock chambers, personnel protective measures, removal methodologies, medical surveillance/environmental monitoring procedures, waste packaging and disposal practices.

The East Bay Municipal Utility District (EBMUD) has evaluated and resolved several puzzling distribution system water quality concerns which periodically plague most water utilities. Excessive coliform growths, complaints of medicinal tastes and odors, and tetrachloroethylene found in treated waters were all traced to different synthetic organic coatings used to protect the interior surfaces of steel storage tanks. After the repeated failure of several attempts to eliminate these problems, the coatings were removed and replaced. Procedures for approving all new coatings were developed. Complaints of petroleum and gasoline taste and odors were demonstrated to be due to the gasoline permeability of polybutylene and polyethylene service laterals. Copper service laterals are now used as a substitute when needed. The district's gas chromatograph made it possible to solve some of these frustrating mysteries. Although the use of probes, coupons, and chemical indices is helpful in evaluating corrosion problems, the District determined that there is no substitute for the physical inspection of the system. The use of a particle counter and a transmission electron microscope was instrumental in determining the effects of corrosion control practices on particulate and asbestos levels in distributed waters.

Slags produced from the entrained flow gasification and cyclonefurnace combustion of Pittsburgh seam coal are morphologically similar and exhibit similar leaching behavior. Both wastes consist predominantly of dense glassy shards with low specific surface area $(<1m^2/g)\text{.}$ Based on aqueous extraction and inorganic analyses according to the extraction procedure specified under the Resource Conservation and Recovery Act (RCRA), none of the combustion or gasification solid wastes examined in this study would be classified as hazardous under current federal regulations. The concentrations of most trace elements in RCRA and other batch extracts of the gasification slag and combustion bottom wastes were below current or proposed drinking water levels. In contrast, arsenic, cadmium, chromium, selenium, zinc, manganese, copper, and sulfate in batch extracts of two combustion fly ashes from Pittsburgh coal exceeded drinking water criteria. These results suggest that slags from entrained flow coal gasification should not require solid waste management practices substantially different from those currently used for coal combustion solid wastes.

The study of RBC scale‐up was conducted by using more than 60 data sets obtained from the operation of full‐scale and pilot‐scale treatment plants. The mathematical model developed earlier by Wu, et al. along with the nonlinear least squares regression method were used to analyze the data and also to determine the process scale‐up factor (SUF). The relationship between SUF and wastewater temperature under different operating conditions was successfully established. An example is given to demonstrate the usage of the SUF for full‐scale plant design.

A mathematical model to describe the changes in the particle size distribution immediately below the solid/liquid interface in gravity thickening was formulated and tested against experimental results. The distribution is predicted to change by coagulation and differential sedimentation. Modifications to the collision efficiency functions for Brownian motion, fluid shear, and differential sedimentation were necessary to account for the high concentrations in thickening. The model correctly predicted the observed trends for both the coagulation and differential sedimentation aspects of the experimental results for changes with time, solids concentration, particle stability, and the subsidence velocity of the interface. The model is limited by the fact that the subsidence velocity cannot be predicted and by the simplified approach to the hydrodynamics of differential sedimentation which is incorporated. The substantial agreement between the model and experimental results indicates that the conceptual approach of the model is well‐founded. The lack of agreement in some cases also has led to further insight into the mechanisms of particle transport in a concentrated heterodisperse suspension.

Ninety‐two treated and untreated sewage samples from seven wastewater treatment plants In Chicago, Illinois, Memphis, Tennessee, and Cincinnati, Ohio were examined for their virus content. Concentrated and unconcentrated samples were plaque assayed in five different cell culture systems. The virus etiology of plaques was confirmed by passage in homologous cell fluid cultures. Including all plaques tested, only 16.5 percent were confirmed as of viral origin. BGM cultures produced the greatest number of unconhrmable plaques. Confirmed virus concentrations for individual samples ranged from less than 0.2 to 80 PFU/1. Confirmed PFU's/1 averaged 0.7 for raw sewage, 0.5 for preliminary effluents and were not detected in final effluents. A strong recommendation of this study is that the virus etiology of all environmentally derived plaques must be confirmed.

Phenol concentration in waste effluents generally varies from 10 mg/L–10,000 mg/L. With a continuous operating adsorption system provided at the source of pollution phenol concentrations may be reduced to levels low enough to be disposed of by available dilutions. Moving media adsorption systems using charcoal as sorbent had been tried and the phenol removal was found to be 40%–70%. The effect of variation in the influent flow rate, coal mass input rate, and size of coal particles on the equilibrium concentrations, were studied. The dynamic system of moving media adsorption has not been found to follow the conventional isotherms. An attempt has been made to develop an isotherm for such a dynamic system.

A method for the optimal design of multisource, looped, gravityfed water distribution systems subjected to a single loading pattern is illustrated through a design example. The proposed methodology uses linear programming (LP) techniques for two different purposes. Initially, an LP problem similar to the classical transportation problem is formulated and solved to obtain the design distribution graph. This system is then optimized by successively formulating (if necessary) and solving an LP problem for obtaining the locally optimal solution. General comments on the suggested methodology and the limitations are also presented.

An analysis is presented defining the distribution of an organic chemical in the water and bed of an estuarine system. The present structure of the model is a tidally averaged two‐dimensional (longitudinal‐vertical) main channel interacting with lateral embayments. The water column, segmented into two layers to incorporate the typical estuarine circulation, interacts with a bed which is also segmented into two layers, an active transport layer and a deeper stationary bed. Adsorption‐desorption kinetics are included which, in the case of Kepone distribution of the James River, are assumed to be at equilibrium. Both steady‐state as well as time‐variable conditions are analyzed to calibrate the model to reproduce presently observed concentrations of Kepone. A procedure of analysis to address the problem of organic chemicals in estuaries has been structured. The procedure involves a series of analytic and computational steps, relating to the fluid transport, the solids distribution, and the concentrations of the organic chemical in the water and the bed. The model has been applied to analyze the temporal and spatial distribution of Kepone in the James River under both constant and time‐variable freshwater flow conditions. Using actual hydrology and an assumed mass rate of input of Kepone, the concentration was calculated for a 10‐yr period of production, comparing well to observed values in the water and bed. Projections are presented to estimate the mass contained in the bed and that discharged to Chesapeake Bay.

Laboratory and design procedures have been developed for chemical clarification of dredged material containment area effluents based on results of laboratory and field tests. The design is suitable for normal disposal operations including remote locations, high and variable flows and solids loadings, and temporary and intermittent operation. The treatment system requires minimal equipment and operation. Low viscosity, highly cationic liquid polymer is applied at the drainage structure of the primary containment cell. Mixing for dispersing polymer and flocculation is provided by turbulence of flow through the discharge culvert. A small secondary cell is used for settling and storage of treated material. Design parameters are determined by jar tests. Major cost components are polymer, labor, and construction. The cost for equipment, labor, and polymer should range from $\$0.08/{\mathrm{yd}}^3-0.25/{\mathrm{yd}}^3$ $(\$0.10/m^3-0.33/m^3)$ (1981 dollars) of in situ sediment dredged and is dependent on the production rate, polymer dosage, and treatment system design.

The use of stormwater detention basins for the dual purpose of flood control and mitigation of pollutant runoff loads has been promoted. However, only limited data and methods for analysis and prediction of pollutant removal in detention basins exist. This paper presents the results of a stormwater quality sampling program conducted to describe the particle size distribution and the time variable influent and effluent concentrations of chemical oxygen demand, total phosphorus, total kjeldahl nitrogen, and solids during various storm events. Concentrations in three separate particle size ranges for each of the four parameters was determined. The basin is shown to be generally effective in reducing solids, chemical oxygen demand (COD), and total phosphorus. Total kjeldahl nitrogen (TKN) concentrations and loadings were generally increased. The effectiveness of the detention basin in reducing pollutant loads appears to be related to two factors, namely, equalization and sedimentation. Dry weather water quality in the detention basin determines the importance of the former, whereas the particle size distribution for each pollutant determines the degree of sedimentation.

Using a three‐cylinder batch unit with an incorporated dissolved oxygen probe, as well as a full‐scale continuous flow unit, for DAF tests, the relationship between polymer residual in the effluent and general performance was studied. A simple titrimetric procedure, sensitive to 1 mg/L, was used for residual polymer measurements, and the Zeta potential for the effluent solids was also obtained. It was found that below a polymer dose of about 4 mg/g of dry solids for the batch unit, there was no improvement in the thickening performance (or float solids concentration), that no residual polymer could be detected in the effluent, and that there was no effect on the negative Zeta potential. Above this dose, there was a step‐wise improvement in the thickening behavior, no further reduction in effluent SS, a detectable residual polymer, and a change to a positive value of the Zeta potential. A similar pattern was observed in full‐scale tests. Thus, it is suggested that polymer residual or Zeta potential measurements could be used for polymer dosage control. Both methods are quicker than the SS measurements, can differentiate between lack of polymer or another cause of performance deterioration, and show how much polymer overdosing had occurred.

Procedures have been developed for designing dredged material sedimentation basins. These procedures can also be used for designing sedimentation basins for other slurries having high suspended solids concentrations. Dredged material sedimentation basins are slightly different from those used in water and wastewater treatment in that the dredged material basins must provide for sedimentation to achieve acceptable ef0uent quality while providing storage volume for several years of material dredged from local waterways. Guidance is presented for field sampling and laboratory testing required to obtain data for sediment characterization, data analysis, sedimentation basin (containment area) design, and estimating storage capacity required. Settling tests performed in a 8‐in. (20 cm) diam column were found to be satisfactory for defining dredged material settling behavior. Settling behavior in the freshwater environment was best described by a flocculent settling test, while behavior in a salt‐water environment was best described by a zone settling test. Procedures are presented for designing new containment areas for suspended solids retention and for evaluating the suspended solids retention potential of existing containment areas during planned disposal activities. The field verification work performed during this research indicated that conservative values could be estimated from laboratory tests for solids concentrations expected in the dredged material sedimentation basins.

Ground water contaminant transport was investigated from a municipal wastewater infiltration system. Ground water quality samples were collected at the Fort Devens, Massachusetts facility from surrounding wells and were analyzed for conductivity and trace level organics contamination. Groundwater flow and chloride contaminant transport were predicted using a two‐dimensional numerical simulation model. Dispersion estimates were made using organics data collected at adjacent wells and adjusted for adsorption in the porous media. Results for field dispersion compared favorably with other values reported in the literature. Methods used in this field project along with modeling techniques should be applicable to other ground‐water waste contaminant sites.

The nitrogen and phosphorus loads to a waterbody may be reliably estimated on the basis of the waterbody's watershed land use pattern and the nitrogen and phosphorus export coefficients for each dominant type of land use. Good agreement was found in a comparison between the nitrogen and phosphorus export coefficients developed in this study and the measured amounts of nitrogen and phosphorus transported to 38 U.S. waterbodies. Good agreement was also found between the load estimated by the Vollenweider model relating the mean annual in‐lake and inflow phosphorus concentrations of a waterbody, and the measured amounts of phosphorus that actually entered the 38 waterbodies.