POSSIBILITIES OF INCREASED WATER SUPPLY FROM CLOUD SEEDING1

ABSTRACT. A review of the development of weather modification to augment precipitation including the cloud-physical foundation is presented. Recent work has tended to re-emphasize the importance of physical understanding of storm systems and of the effects of cloud seeding. The Pyramid Lake Seeding Project is discussed.     

The 1998 Flood in Bangladesh: Is Different Targeting Needed During Emergencies and Recovery to Tackle Malnutrition?

Bangladesh suffered the century's worst flood during July-October 1998 and appealed for assistance. To provide information for appropriate interventions to tackle nutritional problems, a rapid assessment survey was conducted to look at the nutritional situation, problems encountered by the community, their coping mechanisms and rehabilitation priorities in six rural areas. The survey was repeated after four months to measure the outcome of activities during the flood and the necessity for future assistance. There were 3,048 children measured in both surveys (1,597 and 1,451). The sample of most interest was a sub-group of 180 children present in two previous independent surveys. The analysis found that while moving from the crisis period to post-flood phase there was evidence of a 'crossover phenomenon' in the recovery pattern of nutritional status. Sixty-eight per cent of the children who were malnourished (WHZ < -2SD) during the crisis period (18 per cent) recovered enough to cross the cut-off point and became normal after four months. Another 8 per cent of children (9 per cent of all normal) who were normal during the crisis period, after four months had deteriorated to be malnourished. Thus, despite there being a shift in the overall distribution of nutritional status, there has been another shift that reduced the net effect. Subsequent episodes of diarrhoea, access to food and loan burden had also influenced the recovery pattern of the children's nutritional status as evident from the statistically significant associations. These findings raise questions about targeting acute malnutrition during emergencies, and using the same criteria during both the crisis and rehabilitation phases.     

A survey of forest workers in New Zealand. Do hours of work, rest, and recovery play a role in accidents and injury?

PROBLEM: A number of structural and organizational changes have occurred recently within the New Zealand Forestry Industry, with concerns being raised about the impact of these changes on the forestry worker in terms of fatigue, sleepiness, and compromised safety. This study explored the relationship of fatigue, and some of its key determinants, with accidents and injuries in a group of forestry industry workers in New Zealand. METHOD: A total of 367 forestry workers responded to a self-administered questionnaire. RESULTS: Fatigue was found to be commonly experienced at work in the forest, with 78% of workers reporting that they experienced fatigue at least "sometimes." This study found that certain groups of workers reported long working hours, reduced sleep, compromised recovery time, and intensely paced work. The results of logistic regression analysis showed that recent sleep, number of breaks taken during the workday, and specific job/tasks were independently associated with reporting of high fatigue levels at work. Near-miss injury events were significantly more common among those reporting a high level of fatigue at work. Accidents and lost-time injury were associated with length of time at work, ethnicity, and having had near-miss injury events. DISCUSSION: Together, these results suggest that fatigue and aspects of work organization, which are likely to be fatiguing, may be associated with compromised safety for forest workers. IMPACT ON INDUSTRY: With an already slim margin of error present in forest operations, an impairment due to increased fatigue may constitute a significant risk factor for accidents and injuries in this workforce. The results indicate the need for further examination of shift and workload management among forestry workers, as well as a role for improving industry awareness about the causes and consequences of fatigue.     

An assessment of the reported leakage of anthropogenic radionuclides from the underground nuclear test sites at Amchitka Island, Alaska, USA to the surface environment

Three underground nuclear tests representing approximately 15-16% of the total effective energy released during the United States underground nuclear testing program from 1951 to 1992 were conducted at Amchitka Island, Alaska. In 1996, Greenpeace reported that leakage of radionuclides, 241Am and 239+240Pu, from these underground tests to the terrestrial and freshwater environments had been detected. In response to this report, a federal, state, tribal and non-governmental team conducted a terrestrial and freshwater radiological sampling program in 1997. Additional radiological sampling was conducted in 1998. An assessment of the reported leakage to the freshwater environment was evaluated by assessing 3H values in surface waters and 240Pu/239Pu ratios in various sample media. Tritium values ranged from 0.41 Bq/l +/- 0.11 two sigma to 0.74 Bq/1 +/- 0.126 two sigma at the surface water sites sampled, including the reported leakage sites. Only at the Long Shot test site, where leakage of radioactive gases to the near-surface occurred in 1965. were higher 3H levels of 5.8 Bq/1 +/- 0.19 two sigma still observed in 1997, in mud pit #3. The mean 240Pu/239Pu for all of the Amchitka samples was 0.1991 +/- 0.0149 one standard deviation, with values ranging from 0.1824 +/- 1.43% one sigma to 0.2431 +/- 6.56% one sigma. The measured 3H levels and 240Pu/239Pu ratios in freshwater moss and sediments at Amchitka provide no evidence of leakage occurring at the sites reported by Buske and Miller (1998 Nuclear-Weapons-Free America and Alaska Community Action on Toxics, Anchorage, Ak, p.38) and Miller and Buske (1996 Nuclear Flashback: The Return to Anchitka, p.35). It was noted that the marine sample; 240Pu/239Pu ratios are statistically different than the global fallout ratios presented by Krey et al. (1976) and Kelley, Bond, and Beasley (1999). The additional non-fallout component 240Pu/239Pu ratio, assuming a single unique source, necessary to modify the global fallout 240Pu/239Pu ratio to that measured in the marine samples is on the order of 0.65 (Hameedi, Efurd, Harmon, Valette-Silver, & Robertson, 1999; Kelley et al., 1999). While this potentially suggests another plutonium source, such as high burn-up nuclear reactor fuel, rather than underground nuclear tests, the uncertainties in analyses and environmental processes need to be fully assessed before any conclusion can be reached. Further work is needed to evaluate these findings and to support any radiological assessment of the marine environment surrounding Amchitka. Based on geohydrological testing and modeling, leakage from the Amchitka Underground Nuclear Tests is projected to occur to the marine environment (Claassen, 1978; Fenske, 1972; Wheatcraft, 1995).     

The fate of acephate and carbaryl in water.

Acephate was resistent to hydrolysis in distilled, buffered water at pH 4.0 to 6.9, but not at pH 8.2, held for 20 days at 20 or 30 degrees C. The maximum conversion to methamidophos was 4.5% of the added acephate at pH 8.2 and 20 degrees C. The persistence of acephate in two natural waters, held at 9 degrees C for up to 42 and 50 days varied: 80% were recovered from pond water after 42 days, and 45% from creek water after 50 days. Rates of acephate degradation increased greatly when treated water samples were incubated in the presence of sediments, but not if water and sediment were autoclaved prior to treatment and incubation. The greatest conversion to methamidophos, 1.3% of the added acephate, had occurred after 42 days in pond water without sediment. Under the same conditions, carbaryl was less persistent than acephate in the natural waters: 18 to 20% were recovered from pond water after 42 days, and 37 to 40% from creek water after 50 days. The presence of sediment did not affect its degradation significantly. But more than 55% were recovered after 50 days if water and sediment were autoclaved prior to treatment and incubation. Neither acephate, methamidophos, nor carbaryl could be shown to escape from water into the atmosphere.     

Golden Genesis and the Teotonio Vilela Foundation: commercializing PV residential electrification with a not-for-profit partner

This article presents a case study of a project which provides photovoltaic-based rural electrification in the state of Alagoas in northeastern Brazil. The project, the Luz do Sol Programme (LdS), was initiated in mid-1996 by the Golden Genesis Company (Golden) and the Fundação Teotônio Vilela (FTV). The article emphasizes some noteworthy characteristics of the project: the partnership between US commercial and Brazilian philanthropic interests; the financial aspect, a dedicated line of credit requiring only the equipment itself as security; and the local ownership and management of system operations, collections, and routine maintenance.
In 1996, the Golden Genesis Company had developed a central battery charging system to bring the price of electrification within the range of the rural poor; it financed the US content of the systems, with the Bank of the Northeast of Brazil (BN) financing the Brazilian content. The article traces the long and arduous path to establish the programme, including both bureaucratic and technical challenges. These difficulties brought the project to an impasse in August of 1998, and Golden withdrew. FTV then re-negotiated the agreement with BN, changing the technical approach to individual solar home systems. This improved the situation, and the project has since enjoyed 100% loan repayment rates from the entrepreneurs. In June 1999, BP/Solarex became FTV's new commercial partner. The project currently shows promise of becoming the commercially viable programme originally envisaged by Golden, with commercial and technical decision-making at the local level.     

Sensitivity analysis for setting soil cleanup standards

In recent years, many states have sought to set soil standards for hazardous waste sites. For example, Michigan and Oregon have had soil standards for several years, and within the last three years Massachusetts, New Jersey, Pennsylvania, and Texas have derived soil standards; while Illinois and several other states are in the process of developing soil standards. In general, soil cleanup standards are set to protect against leaching to groundwater and direct contact with soil. This article reviews several agencies' protocols and presents a sensitivity analysis of parameters used to establish these soil cleanup standards. Major issues examined in this article include land use (residential versus commercial/industrial) and exposure parameters used for deriving soil cleanup standards for direct contact. Soil cleanup standards are developed considering exposure routes such as ingestion, dermal contact, inhalation of vapors, and fugitive dust. Other factors such as chemical/physical properties are also considered. For example, many states use Toxicity Characteristic Leaching Procedure (TCLP) or EPA Method 1312 Synthetic Precipitation Leaching Procedure (SPLP) to derive soil standards protective of leaching to groundwater. The results indicate that factors such as leaching and certain exposure assumptions play a key role in determining soil cleanup standards. Exposure pathways were examined by performing a sensitivity analysis using a generic equation to consider exposure from ingestion, dermal contact, and inhalation of soil in deriving soil cleanup standards. The sensitivity analysis indicates that selection of exposure parameters such as toxicity values and soil-to-skin adherence factors contribute more substantially than others. These two factors are also among those values with the greatest uncertainty. Selection of exposure pathways is also important for the derivation of soil cleanup standards. For example, inhalation is the most significant exposure pathway for volatile organic compounds such as toluene, yet many states do not evaluate this exposure route. These findings are based on the mathematical models used by the agencies, and no judgments are made on the validity of the models. The results of this analysis can help focus attention on the most sensitive parameters as federal government reforms environment policies (i.e., CERCLA and RCRA) and the development of national soil cleanup standards is debated.     

Alternative method of groundwater sparging for petroleum hydrocarbon remediation

An alternative method of in-situ groundwater sparging, termed density-driven convection (patent pending), is presented. This method has been successfully used to remediate eight underground storage tank releases involving a wide distillation range of petroleum hydrocarbons (gasoline to waste oil) and in a variety of site soils (clay to sandy gravel). Application of the density-driven convection method is detailed in a case study. The system, installed to remediate a gasoline and diesel release from an underground storage tank, was operated and monitored for a period of one year. Monitoring data indicate reductions in total petroleum hydrocarbon concentrations in groundwater and in soil. Concentrations of aromatic hydrocarbons (benzene, toluene, ethylbenzene, xylenes, and naphthalene) also decreased in both media. Stimulation of natural biodegradation, the primary mechanism of removal, occurred rapidly. Natural biological activity gradually declined over the subsequent 150 days. After one year of operation, the sparging system has achieved or is rapidly approaching the regulatory cleanup goals for both soil and groundwater, including reduction of dissolved concentrations below maximum contaminant levels established under the Safe Drinking Water Act.