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The purpose of this study was to assess Air Force compliance with the Endangered Species Act of 1973, as amended (16 USC 1531, et seq.) through an examination of the natural resource management programs on selected installations. The method of approach was an internal document search and personal involvement. Four installations with an endangered species in common, the red-cockaded woodpecker (Pocoides borealis), and a single installation, Andersen Air Force Base, Guam, with nine endangered species were selected for analysis. The Air Force is not in complete compliance with the Act. Natural resource managers are not employed at three of the five installations. The endangered species programs do not dominate the resource management programs as strict interpretation of the law would require. Determination of compliance is not only a factor of the evaluation of the biological program, it must include an assessment of the guidance and regulation provided by the law. A sufficient body of case law has not been developed to fully define compliance, however, the indications are that strict interpretation of the Act is neither ecologically nor politically possible. The Air Force cannot comply with the law, biologically, politically, or budgetarily. The Air Force recognizes the pragmatism of wildlife management and will continue "business as usual" with endangered species management programs until a threat of legal action puts emphasis on an installation. Ultimately, court decisions will determine the appropriate compliance in each situation.

Dissolved air flotation (DAF) is an attractive solid/liquid separation process for highly colored, low turbidity water supplies. Low density floc is produced when these waters are coagulated, therefore DAF may be more effective than conventional gravity settling (CGS). Communities required to filter their supplies should consider DAF as an alternative pretreatment prior to filtration. Although DAF is a promising alternative to CGS, no rational basis has been developed for selection, design and operation of DAF facilities. The research objectives were: (1) to develop a fundamental basis for the application of DAF to water treatment, (2) to determine via experiment the key variables which affect DAF performance for the removal of clay turbidity and natural organic matter (NOM), and (3) to compare DAF to CGS. A conceptual model was developed based on colloidal stability and particle deposition and used to identify the variables which affect DAF. The variables which included pH, coagulant type and dose, temperature, DOC and clay concentrations, flocculation time, DAF detention time, and bubble concentration were studied using synthetic waters. Synthetic waters were used to compare DAF to CGS. Synthetic waters were prepared from extracted aquatic fulvic acid and research grade montmorillonite clay--their use allowed water quality variables to be carefully controlled. Synthetic water results were then verified using two natural waters. Modelling predicted that particle stability and size, bubble size and rise rate, bubble volume concentration, and detention time would affect DAF performance. Experiments indicated particles must be coagulated for successful flotation. Temperature and flocculation time affected DAF performance in experiments using alum. It is hypothesized that the effects of cold temperature on DAF performance are due to changes in coagulation mechanism and the physical and chemical stability of the particles as it relates to charge and bound water at the surface. In addition, bubble volume affected DAF performance for high DOC waters and waters containing clay. Comparisons of DAF to CGS indicated that the DOC, organic halide precursors, and dissolved aluminum after treatment were comparable for both. However, DAF produced significantly lower turbidities than CGS, particularly at colder temperatures.

Humic substances (HS) are major components of soil organic matter (SOM). Advances on characterization of HS and their interaction with minerals can provide a more fundamental understanding of HS functions in soils. The objectives of this research were to investigate potential fractionation of humic acid (HA) upon adsorption on minerals and to determine any variation on structure and sorption properties of humin extracted by different methods. Nuclear magnetic resonance (NMR) spectra, for the first time, provided direct evidence that HA was fractionated during adsorption on mineral surfaces. Aliphatic fractions of HA were preferentially adsorbed while aromatic fractions were more likely to be left in solution. The bound HA fractions had higher sorption linearity (N) and affinity (KOC) for phenanthrene than the source HA. For montmorillonite and kaolinite, the KOC values of adsorbed HA were up to several times higher than that of the source HA as a result of fractionation. Extraction procedures had substantial influences in structure and sorption characteristics of humin. Humin from 0.1 M NaOH exhaustive extraction and 6 M HF/HCl extraction at 60°C had relatively more aliphatic components as compared with 1 M HF extracted humin. The treatment of 6 M HF/HCl at 60°C reduced more than 50% carbohydrate components (50-108 ppm) and enriched amorphous poly(methylene) domains. The NaOH exhaustively extracted humin had the most nonlinear sorption isotherms and the HF extracted humin had the lowest KOC. We concluded that both NaOH and NaOH-HF procedures were appropriate approaches for humin extraction but the extraction with 6 M HF/HCl at 60 °C would be discouraged for use due to structural modifications of humin both chemically and physically. Segmental mobility of HA in solution was also explored by NMR relaxation. Proton spin-lattice relaxation time (T1) of HAs ranged from 0.3 to 0.8 s in d6-DMSO, and from 0.26 to 2.3 s in 0.5 M NaOD at 300 MHz. Proton correlation time of HA in solvents was in an order of 10-10 s. Carbohydrate was identified as the largest and the most immobile components while aliphatic and aromatic fragments were relatively smaller and more mobile in aqueous solution.

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Humic substances (HS) are the major components of soil organic matter (SOM), which are by far the most abundant organic materials in the environment. Advances on structural characterization of HS and their interaction with clay minerals will provide a more fundamental understanding of HS functions in such important roles as sorption of anthropogenic organic contaminants, stabilization of soil aggregates, and C sequestration. The objectives of this research were to determine any variation in structure and sorption properties of humic acids (HAs) and humins sequentially extracted from a soil and investigate characterization and fractionation of HA and relatively small carboxylic acids upon adsorption on clay minerals. In a phenanthrene sorption study of sequentially extracted HAs and humins, there were significant chemical and structural differences among the HA fractions and humins, and sorption was greatly affected by chemical structure and composition of humic substances, even from the same soil. A positive trend was observed between the sorption coefficient and the aliphaticity. Humin fractions with the highest aliphatic C contents and the lowest polarity showed the highest sorption capacity and nonlinearity as compared with the HAs. A negative relation was shown between the sorption capacity and polarity of HAs. The aliphatic-rich SOM in this study had less polar moieties, but had relatively high Koc. Therefore, the polarity of SOM is likely one of the important parameters controlling sorption of hydrophobic organic chemicals (HOCs). Adsorption of SOM onto clay minerals modifies their surfaces and reactivity and strongly influences the fate of organic contaminants and other species in soils and sediments. For investigation of the structural and conformation changes of HA and clay-HA complexes after sequential adsorption by goethite, kaolinite, and montmorillonite, UV-Visible spectroscopy, high performance size exclusion chromatography (HPSEC), Fourier transform infrared (FT-IR) spectroscopy, and solid-state 13C nuclear magnetic resonance (NMR) spectroscopy were employed. Aliphatic rich HA fractions with polar functional moieties readily adsorb to the goethite surface, while aromatic fractions were left in solution. Similar to HA fractionation onto goethite, paraffinic fractions and polar aliphatic fractions sorbed preferentially on montmorillonite, but aromatic functional moieties likely remained in solution. However, paraffinic fractions were observed on kaolinite surfaces although the adsorbed proportion of these fractions was low. Because of high broken edge areas, kaolinite has more adsorption sites for carboxylic and carbonyl rich fractions than montmorillonite. With respect to MW fractionation after sorption, relatively low molecular weight (MW) HA fractions had a greater affinity for the goethite surface from the analysis and inference of the HPSEC chromatograms, which differs from the reported results in the literature. The low MW HA fractions might be intercalated into the interlayer of montmorillonite and high MW HA fractions adsorbed on external surfaces, which results in the adsorption of relatively wide range of MW HA fractions. The binding mode of small HA fractions on the clay minerals may be ligand exchange and/or electrostatic interaction, which gives HA-clay complexes new hydrophobic sorption sites for high MW HA fractions. To obtain information on the nature of the interactions between SOM and clay mineral surfaces, the adsorption of dicarboxylic acids by kaolinite and montmorillonite at different pH conditions was investigated using in situ attenuated total reflectance Fourier transformed infrared (ATR-FTIR) and ex situ diffuse reflectance infrared Fourier transformed (DRIFT) spectroscopy. The sorption was highly pH dependent and related to the surface characteristics of minerals; adsorption of dicarboxylic acids (succinic acid, glutaric acid, adipic acid, and azelaic acid) was the highest at pH 4 as compared with those at pH 7 and 9, and the sorption capacity of montmorillonite was greater than that of kaolinite. Furthermore, the complexation types, inner- or outer-sphere, depended upon dicarboxylic acid species, pH, mineral surfaces, and solvent conditions. Most samples tend to have outer-sphere adsorption with the mineral surfaces at all tested pHs. However, inner-sphere coordination between the carboxyl groups and mineral surfaces at pH 4 was dominant with freeze-dried complex samples. Therefore, organic acids in an aqueous environment prefer to adsorb onto kaolinite and montmorillonite by outer-sphere complexation, but inner-sphere complexation is favored under dry conditions. These results imply that organic acid binding onto clay minerals under dry conditions is stronger than that under wet conditions. The stable NOM/mineral complexes formed by frequent wetting-drying cycles in nature may resist chemical/microbial degradation of the NOM, which will affect carbon storage in the environment and influence the sorption of organic contaminants.