RESULTS OF ACIDIZING WATER WELLS IN ARIZONA1

Two wellfields have been developed to provide water for a coal fired electric generating station in Arizona. Wellfield No. 1 penetrates the unconfined Coconino Sandstone aquifer, and wellfield No. 2 penetrates the composite Kaibab Limestone-Coconino Sandstone aquifer where ground water occurs under confined conditions. A well in each wellfield was pumped and water level drawdown data were collected before and after acidizing. The drawdown data at the various pumping rates were analyzed to determine the potential benefits of acidizing production water wells in both wellfields. After acidizing, the specific capacity of the well in wellfield No. 1 was improved about 50 percent at water production rates ranging from about 200 to 500 gallons per minute (gpm) (13 to 32 liters per second (lps)). After acidizing, the specific capacity of the well completed in wellfield No. 2 was improved about 100 percent at pumping rates ranging from about 1,250 to 2,200 gpm (79 to 139 lps). An annual saving of approximately 11 percent in pumping costs can be realized in wellfield No. 2, and savings are approximately four percent in wellfield No. 1. Acidization is beneficial for wells that can produce more than 500 gpm (32 lps), and is of marginal value for those that produce less than that amount.     

1976 Illinois drought: Evidence for improved water quality

During 1976, Illinois experienced a mild drought, of i ntensity equivalent to the once in 5 years frequency. It was anticipated that the drought would result in deteriorated water quality because dilution of point source discharges would be diminished. Furthermore, because productivity in Illinois streams is light limited, reduced runoff should result in clearer streams, higher algae levels, and greater variability in dissolved oxygen levels. In spite of these expectations, both chemical and biologic data showed that water quality in 1976 was appreciably better than that before 1975. The information provided by the Illinois water quality index (Janardan and Schaeffer 1977) coincides with biologic analyses of benthic invertebrates. The index supports and supplements the biologic data and provides a means for quantifying and integrating chemical and biologic data.The results of this study showed that the drought had little, if any, effect on statewide water quality. Although the magnitude of the drought varied across the state, water quality remained unchanged between 1975 and 1976. This may have reflected the ability of unpolluted systems to adjust to natural variations or have been an indication that there were offsetting statewide gains in pollution control in 1976 or that uncharacterized, broad-based phenomena were operating in stream ecology, or that combinations of these were in effect.Based on presentations before the American Water Resources Assocition, Illinois Section, Chicago, Illinois, June 10–11, 1977.     

CHANNELIZATION AND INVERTEBRATE DRIFT IN SOME IOWA STREAMS1

ABSTRACT: Habitat diversity and invertebrate drift were studied in a group of natural and channelized tributaries of the upper Des Moines River during 1974 and 1975. Channelized streams in this region had lower sinuosity index values than natural channel segments. There were significant (P=O.05) positive correlations between channel sinuosity and the variability of water depth and current velocity. Invertebrate drift density, expressed as biomass and total numbers, also was correlated with channel sinuosity. Channelization has decreased habitat variability and invertebrate drift density in streams of the upper Des Moines River Basin and probably has reduced the quantity of water stored in streams during periods of low flow.     

PROCEDURES FOR THE EVALUATION OF ENGINEERING ALTERNATIVES1

ABSTRACT: This paper describes a method of analyzing the nonquantifiable parameters which should be considered in the evaluation of engineering alternatives. The nonquantifiable parameters can include environmental impact, feasibility of implementation, and performance. The method considers rating all the alternatives on the basis of a set of criteria which reflect these parameters. A procedure is discussed for obtaining review and guidance in the evaluation of engineering alternatives from the local elected officials or governing bodies and for obtaining the views and desires of the local communities. This is achieved through the formation of project review committees and an evaluation procedure which allows for the technical rating of alternatives by the engineer and the weighing of the evaluation criteria by the political and social groups. With the growing environmental concern and the high cost of engineering projects, the involvement of the public during the evaluation of engineering projects is becoming increasingly important to the final success of the project.     

Urban waterfowl population: Ecological evaluation of management and planning

An urban population of ducks in Puyallup, Washington, USA was studied for 14 consecutive months beginning in November 1978. Observations were made weekly from four study sites where ducks would congregate at early morning hours. Factors contributing to the presence of waterfowl in Puyallyup included abundant food supplies and a creek corridor that connected fragmented habitats in the urban area to the larger rural populations of waterfowl. Mallards (Anas platyrhynchos) were the most abundant of the 13 species observed and were the only ducks remaining during the nesting season. Habitat size and complexity were important factors influencing the species diversity of a particular site. Nesting success of mallards was poor due to limited distribution of nesting habitat, intraspecific aggression, and human disturbance. Both site-specific and more broad-based strategies are suggested for managing and planning for duck populations in urban areas.     

Slash fire hazard analysis on the Siskiyou National Forest

Potential increase in fire hazard as a result of timber harvesting is a concern of forest managers throughout the United States. Treating fuels can help reduce unacceptable fire hazards. To evaluate alternative fuel treatments, managers need to know their effects on fire hazard. A decision analysis approach to estimating fire hazard in terms of expected burned area was applied to a watershed in the Siskiyou National Forest (Oregon). Three treatment alternatives (do nothing and two levels of yarding unmerchantable material) were evaluated, and the effects of the treatments were projected over a 90-yr period. Initially, the effects of applying a treatment are small. After 50 years of treatment, the most intense alternative can be expected to show almost a 50% reduction in burned area compared to no treatment. The procedure also estimates burned are by fire size and fire intensity classes. Managers may find this useful for estimating expected fire effects associated with a particular fuel treatment regime.     

Strategies for controlling hazards at work

This paper presents an heuristic framework for analyzing hazards (potential for loss or harm) and strategies that may be developed to control their realization. Two basic forms of intervention for hazard control (anticipation and reaction) are identified. Three broad anticipative strategies are discussed: (1) elimination of the source of the hazard, (2) containment of the risk of its realization, and (3) mitigation of likely consequences. The communication and judgmental processes involved in decisions about strategies are shown to be embedded in the organizational “political” context, in which a variety of interests backed by varying sources of power and influence are represented. The development, implementation, and monitoring of any strategies that are decided upon are then discussed, including the fact that such actions and events may not produce the intended results. Comments are also made on the need for data provided by monitoring to be evaluated and appropriate adaptations made. Finally, a brief section of the paper discusses reactive strategies.