Scope effects of respondent uncertainty in contingent valuation: evidence from motorized emission reductions in the city of Nairobi,Kenya

This study analyzed the scope effects of respondent uncertainty in contingent valuation (CV) by evaluating whether willingness to pay (WTP) estimates were sensitive to changes in the magnitudes of motorized emission reductions in the city of Nairobi, Kenya. The WTP estimates were elicited through the conventional payment card (PC), stochastic payment card (SPC) and the polychotomous payment card (PPC) formats. While SPC and PPC formats were used to capture respondent uncertainty, the PC format captured respondent certainty regarding the amounts individuals were WTP for emission reductions. Based on parametric and nonparametric analysis, results show that certain (PC) respondents stated significantly larger WTP amounts for larger emission reductions than for smaller reductions. Conversely, uncertain (SPC and PPC) respondents stated smaller amounts for larger emission reductions than certain (PC) respondents. The implication is that though respondents were sensitive to the scope of motorized emission reductions, respondent uncertainty lowered their sensitivity to scope.     

Liability Funding and Superfund Clean-Up Remedies

The debate about Superfund liability has treated financing as a distinct issue from the efficiency of clean-up. However, this paper presents a model of EPA decision-making in which liability funding may increase or decrease the extent of clean-up. It then estimates this effect using data on remedies selected at National Priorities List sites and on the characteristics of liable parties. The results suggest that the EPA responds to concentrated private interests, selecting less extensive clean-up when liable parties are expected to bear a large share of costs. This effect should be considered in evaluating liability approaches to environmental protection.     

Clay charge reversal effects on aqueous polymer sorption on lateritic soils

The effects of charge reversal about the measured point of zero charge (pH(0) approximately 5.2) of untreated and treated Sete Lagoas lateritic soil of Brazil on aqueous polymer sorption was investigated. The polymers are anionic sodium carboxymethyl cellulose (CMCA), nonionic polyethylene oxide (PEO), and cationic polyacrylamide (PAM). They were prepared at aqueous concentrations and pH ranges of 0.1-2.0 g l(-1) and 2-9, respectively. Soil treatment involved the removal of iron oxides by treatment with dithionate-bicarbonate-citrate. Batch sorption test results show that the presence of iron oxides in lateritic soil tends to suppress sorption of CMCA (especially at pH=pH(0)) and PEO (for the whole pH range) but has uncertain effects on cationic PAM sorption. CMCA sorption on the untreated soil improves on either side of pH(0), in direct proportionality to solution concentration, except at pH<4.0, where disassociation of the polymer molecules may decrease sorption energy. Increase in the sorption of non-cationic polymers (CMCA and PEO) at pH>pH(0) is attributable to dispersion of clay, cation bridging and polymer molecular reconfiguration. For cationic PAM, electrostatic bonding to negatively charged soil particle surfaces accounts for the sorption increase. For treated soil samples, polymer sorption pattern is similar to those expected for the montmorillonitic clayey soils of temperate zones. These results indicate that the pH(0) of lateritic soils, within the regime that exists in the field, should be considered in assessing the potential effectiveness of polymer dust suppressants for tropical lateritic soils.     

Planning methodology for predicting spatial patterns of risk potential from industrial land uses

The nature of environmental risk is often determined by the location patterns of industrial firms in a locale. We develop a methodology for analyzing the capacity of toxics-generating industries to leave toxic residuals on the landscape, in the context of long-term master planning. To understand an area's risk profile, we first characterize the location pattern of risk-generating firms and develop ways to represent the risk potentials of these shapes. To this end, we develop a geometric approach for characterizing the spatial patterns of these clusters of dirty industries, using new measures for analyzing spatial densities and compactness. We then introduce context (i.e. actual zoning patterns, transportation corridors) and explain how this relates to the spatial patterns found. We illustrate this analytical method with application to Orange County, California, USA and point out how it affords a deeper understanding of the connections between industry and environmental risk. We end the article with a discussion of how these analytical methods might be used for land use planning.     

Transition to Lead-Free Products in the US Electronics Industry: A Model of Environmental,Technical, and Economic Preferences

The European Union’s Restriction on the Use of Certain Hazardous Substances (Directive 2002/95/EC) targeted at electronic products took effect in 2006. In contrast, the USA has no comparable national policy on these products. To understand corporate responses to policy differences across jurisdictions, we conducted a structured-questionnaire survey of individuals in 109 companies that are representative of the US electronics industry. The results reveal that 70% of these companies have already adopted lead-free solder for electronics with 49% of the total preferring the SnAgCu formulation, despite uncertainties associated with environmental impacts of this alternative alloy. We use a modified life cycle impact assessment method based on endpoint modeling approach to derive weighting factors that represent the respondents’ value system for tradeoffs among environmental impacts. We use a modified fuzzy Technique for Order Preference by Similarity to Ideal Solution approach to evaluate technical criteria dominance in declared preferences. A statistical model of corporate behavior is also presented. The results provide the first systematic framework that accounts for environmental impact, technological challenge, and business strategy concurrently toward formulating a comprehensive national policy for materials selection in electronic products.     

Elemental concentrations in Jamaican peat

The peat of the Negril Morass in Western Jamaica was sampled at depths down to 7 m in directions parallel and perpendicular to the seashore, and the samples were analysed for Al, As, B, Br, Ca, Ce, Cl, Co, Cr, Cs, Dy, Eu, Fe, Hf, I, La, Mg, Mn, Na, Sb, Sc, Sm, Sr, Ti, U and V by instrumental neutron activation analysis and by spectrophotometry. The peat is high in ash content, but the concentrations of most elements are below crustal abundances and therefore provide no evidence of nearby mineralisation. The elemental concentrations indicate that no particular environmental hazards are to expected from the use of this peat in electricity generation.     

Growing an environmental leadership strategy at duke power company

This article presents information on Duke Power Company's environmental leadership strategic measures, targets, and results. Information is presented on how each measure is defined, how progress is measured and reported, what behavior changes have been observed, the results achieved, and what challenges are foreseen in the future.     

Work-related injury and ill-health among mountain instructors in the UK

In most industrialised countries, work-related injury and ill-health presents a major burden to society. Musculoskeletal disorders and stress are the most common reported illness types with those working in some industries more at risk than others. This study aimed to understand the occupational health issues of those working as mountain instructors in the outdoor sector within the UK and to identify the cultural norms and behaviours among this unique occupational group which influence health. Semi-structured, telephone interviews were conducted with 20 qualified mountaineers to gain information on work-related injury and ill-health. The majority of interviewees reported a current work-related musculoskeletal problem. Key factors were identified which prevented effective rehabilitation, including; a ‘macho’ attitude among young instructors, self-imposed extended working hours/days and mismanagement of injuries. Self-employed instructors reported that sick leave after a minor injury or illness was not financially viable. Work-related issues leading to stress were also reported.     

Biomonitors of stream quality in agricultural areas: Fish versus invertebrates

Although the utility of using either fish or benthic invertebrates as biomonitors of stream quality has been clearly shown, there is little comparative information on the usefulness of the groups in any particular situation. We compared fish to invertebrate assemblages in their ability to reflect habitat quality of sediment-impacted streams in agricultural regions of northeast Missouri, USA. Habitat quality was measured by a combination of substrate composition, riparian type, buffer strip width, and land use. Invertebrates were more sensitive to habitat differences when structural measurements, species diversity and ordination, were used. Incorporating ecological measurements, by using the Index of Biological Integrity, increased the information obtained from the fish assemblage. The differential response of the two groups was attributed to the more direct impact of sediments on invertebrate life requisites; the impact of sedimentation on fish is considered more indirect and complex, affecting feeding and reproductive mechanisms.The Unit is sponsored by the US Fish and Wildlife Service, the Missouri Department of Conservation and the University of Missouri.