OPTIMIZING WELL PLACEMENT IN A COASTAL AQUIFER: OUTER CAPE COD,MASSACHUSETTS1

ABSTRACT: An inverse‐simulation approach is used to determine optimal strategies for developing public water‐supply systems in a shallow, coastal aquifer on the outermost arm of the Cape Cod peninsula in Massachusetts. Typically a forward simulation (or “trial and error”) approach is used to find best pumping strategies, but the chances of finding success with this tact diminish as the number of potential options grows large. Well locations and pumping rates are optimized with respect to: (1) providing sufficient water to areas of water‐quality impairment, (2) minimizing impacts to nearby surface waters, (3) preventing saltwater contamination due to overpumping, and (4) minimizing financial cost of well development. Potential well sites and water‐supply scenarios are separated into “politically‐based” and “resource‐based” categories to gain insight into the degree that pre‐existing political boundaries hinder best management practices. The approach provides a promising tool in transboundary water‐resources settings because it allows stakeholders to find solutions that best meet everyone's goals, as opposed to pursuing options that will create conflict, or are less than optimal.     

Use of toxicity identification evaluation techniques to identify dredged material disposal options: A proposed approach

It is common to use the results of various solid-phase and aqueous-fraction toxicity tests as part of the decision-making process for selecting disposal options for dredged sediments. The mere presence of toxicity, however, does not provide a logical basis for selecting economical, environmentally protective disposal techniques. To achieve this, it is necessary to be able to identify specific compounds responsible for sediment toxicity. Toxicity identification evaluation (TIE) procedures, originally developed for complex effluents, represent a useful approach for identifying acutely toxic compounds in dredged materials. Herein we present a conceptual overview for TIE use in part of the decision-making framework for selecting dredged material disposal options; included are discussions concerning appropriate test fractions and species for TIE analyses, and specific TIE manipulations useful for ascertaining whether toxicity is due to any of a number of common sediment contaminants including ammonia, hydrogen sulfide, metals, or nonpolar organics.     

Enhancing biomass energy use in Kenya

This paper argues that in Kenya, environmental and economic factors will favour the continued use of biomass as a primary fuel for household and institutional cooking for the next decade or longer. The paper describes several successful projects which have improved the efficiency of urban charcoal use and of rural woodfuel use. The Kenya Ceramic Jiko, a more efficient version of the traditional charcoal stove, is a model programme sustained by free market competition, artisans participation, and widespread public acceptance. The Maendeleo stove is the best example of a successful rural woodstove project. The performance attributes of the stove, and its promotion through Kenya's largest women's organization, have resulted in the distribution of an estimated 26 000 Maendeleo stoves. Rural stove efficiency will become important as the cash-based economy expands in those areas. Agroforestry will also be critical to an enhanced use of biomass energy in Kenya. Experience to date shows that successful agroforestry programmes will have to be appropriate to local conditions and crops .     

Measuring for success in communications for permits

Today, U.S. corporations are discovering the merit of combining the principles of total quality environmental management (TQEM) into their measurement and communications programs. This approach has been particularly productive in the permitting process that is necessary for starting, expanding, or sustaining plant operations—a procedure that can easily be thwarted in the absence of a prominent and aggressive communications component. The need to benchmark and measure such a communication program'S progress is critical both for internal management and for environmental regulators concerned that an applicant demonstrate a high degree of public involvement.     

ACID PRECIPITATION AND WEATHERING BY ORGANIC ACIDS IN LABRAI)OR LAKE BASINS1

ABSTRACT: Thirty-five lakes in southern Labrador sampled in 1981 were resampled in 1989 and water chemistry values were compared between visits. Results showed higher pH, specific conductance, acid neutralization capacity, color, and base cations values in 1989, though sulfate, the ion most likely to reflect acid precipitation impacts, did not vary. The major ion changes measured were probably due to natural hydrological variations and not to changes in acid inputs. Results from the 1989 data showed a slight, but significant, decrease in water sulfate concentration trend from western to eastern Labrador, though most values, even in the western portion of the study area, fell close to the values considered “background” by Brakke et at. (1989). Base cation concentrations exceeded those which could be predicted from weathering by carbonic and bicarbonic acid. Assuming that little weathering is generated by acid precipitation in this region, the excess cations measured are probably a result of bedrock dissolution from organic acids generated by plant decomposition. Calculations showed that organic acid effect could be responsible for 9 to 52 percent of total weathering in the study basins.     

SPATIAL DISTRIBUTION OF POINT SOIL MOISTURE ESTIMATES USING LANDSAT TM DATA AND FUZZY-C CLASSIFICATION1

ABSTRACT: Many hydrologic models have input data requirements that are difficult to satisfy for all but a few well-instrumented, experimental watersheds. In this study, point soil moisture in a mountain watershed with various types of vegetative cover was modeled using a generalized regression model. Information on sur-ficial characteristics of the watershed was obtained by applying fuzzy set theory to a database consisting of only satellite and a digital elevation model (DEM). The fuzzy-c algorithm separated the watershed into distinguishable classes and provided regression coefficients for each ground pixel. The regression model used the coefficients to estimate distributed soil moisture over the entire watershed. A soil moisture accounting model was used to resolve temporal differences between measurements at prototypical measurement sites and validation sites. The results were reasonably accurate for all classes in the watershed. The spatial distribution of soil moisture estimates corresponded accurately with soil moisture measurements at validation sites on the watershed. It was concluded that use of the regression model to distribute soil moisture from a specified number of points can be combined with satellite and DEM information to provide a reasonable estimation of the spatial distribution of soil moisture for a watershed.     

HYDRAULIC MODELING SUPPORT FOR CONFLICT ANALYSIS: THE MANAYUNK CANAL REVISITED1

ABSTRACT: This paper presents a study which used a standard, hydraulic computer model to generate detailed design information to support conflict analysis of a water resource use issue. As an extension of previous studies, the conflict analysis in this case included several scenarios for stability analysis - all of which reached the conclusion that compromising, shared access to the water resources available would result in the most benefits to society. This expected equilibrium outcome was found to maximize benefit-cost estimates.     

The role of facet importance as a moderator in job satisfaction processes

Two studies were designed to test hypotheses derived from Locke's (1969, 1976, 1984) model of job satisfaction. Consistent with the model, both studies found that perceived have-want discrepancy scores were powerful predictors of facet job satisfaction. In addition, facet importance tended to moderate this relationship in the manner predicted by Locke. Workers who viewed a job facet as having high importance were more satisfied with a small perceived have-want discrepancy and more dissatisfied with a large discrepancy than workers who viewed the facet as having low importance. Finally, as expected, facet importance failed to moderate the relationship between facet satisfaction and overall job satisfaction. This finding supports Locke's proposition that facet satisfaction scores are ‘implicitly weighted’ by facet importance. Implications and directions for future research are discussed.