Air pollution control system testing at the DOE offgas components test facility

In 1997, the Department of Energy (DOE) Savannah River Site (SRS) plans to begin operation of the Consolidated Incineration Facility (CIF) to treat solid and liquid RCRA hazardous and mixed wastes. The Savannah River Technology Center (SRTC) leads an extensive technical support program designed to obtain incinerator and air pollution control equipment performance data to support facility start-up and operation. A key component of this technical support program includes the Offgas Components Test Facility (OCTF), a pilot-scale offgas system test bed. The primary goal for this test facility is to demonstrate and evaluate the performance of the planned CIF Air Pollution Control System (APCS). To accomplish this task, the OCTF has been equipped with a 1/10 scale CIF offgas system equipment components and instrumentation. In addition, the OCTF design maximizes the flexibility of APCS operation and facility instrumentation and sampling capabilities permit accurate characterization of all process streams throughout the facility. This allows APCS equipment performance to be evaluated in an integrated system under a wide range of possible operating conditions. This paper summarizes the use of this DOE test facility to successfully demonstrate APCS operability and maintainability, evaluate and optimize equipment and instrument performance, and provide direct CIF start-up support. These types of facilities are needed to permit resolution of technical issues associated with design and operation of systems that treat and dispose combustible hazardous, mixed, and low-level radioactive waste throughout and DOE complex

DISCREPANCIES BETWEEN LONGITUDINAL AND CROSS-SECTIONAL CHANGE IN VENTILATORY FUNCTION IN 12 YEARS OF FOLLOW-UP

We compared the age dependence of cross-sectional and longitudinal changes in ventilatory function. FEV(1), FVC, and data on chronic respiratory symptoms were obtained from 4,395 adults in a longitudinal survey of normal populations in two different areas in the Netherlands. They participated in up to five surveys at 3-yr intervals between 1972 to 1973 and 1984 to 1985. The ventilatory function in the oldest cohorts is substantially lower than might have been expected from the longitudinal change in the youngest cohorts. This holds for males and females, smokers and nonsmokers, subjects with or without symptoms, and for both survey populations. The robustness of the findings is demonstrated by various data-analytic strategies or omitting one or two of the five surveys from the analysis. Selective loss to follow-up cannot explain the discrepancy. It is concluded that the main differences between our longitudinal and cross-sectional findings may be due to a cohort effect. The implication is that in longitudinal studies of populations at risk, reference equations based on cross-sectional surveys may overestimate longitudinal change and hence lead to underestimating effects of exposure. Similarly, in clinical studies, accelerated decline in ventilatory function may be underrated if it is compared with cross-sectional standards. In older people at any one age the ventilatory function seems to improve in successive birth cohorts

Bird Use of Solar Photovoltaic Installations at US Airports: Implications for Aviation Safety

Several airports in the US have recently installed large photovoltaic (PV) arrays near air-operations areas to offset energy demands, and the US Federal Aviation Administration has published guidelines for new solar installations on airport properties. Although an increased reliance on solar energy will likely benefit airports from environmental and economic perspectives, bird use of solar installations should be exam-ined before wide-scale implementation to determine whether such changes in land use adversely affect aviation safety by increasing risk of bird-aircraft collisions. We studied bird use of five pairs of PV arrays and nearby airport grasslands in Arizona, Colorado, and Ohio, over one year. Across locations, we observed 46 species of birds in airfield grasslands compared to 37 species in PV arrays. We calculated a bird hazard index (BHI) based on the mean seasonal mass of birds per area surveyed. General linear model analysis indicated that BHI was influenced by season, with higher BHI in summer than fall and winter. We found no effect of treatment (PV arrays vs. airfields), location, or interactions among predictors. However, using a nonparametric two-group test across all seasons and locations, we found greater BHI in airfield grass-lands than PV arrays for those species considered especially hazardous to aircraft (species \u3e 1.125 kg). Our results suggest that converting airport grasslands to PV arrays would not increase hazards associated with bird-aircraft collisions