Demonstration of the Military Ecological Risk Assessment Framework (MERAF): Apache Longbow - Hell Missile Test at Yuma Proving Ground

This ecological risk assessment for a testing program at Yuma Proving Ground, Arizona, is a demonstration of the Military Ecological Risk Assessment Framework (MERAF; Suter et al. 2001). The demonstration is intended to illustrate how risk assessment guidance concerning-generic military training and testing activities and guidance concerning a specific type of activity (e.g., low-altitude aircraft overflights) may be implemented at a military installation. MERAF was developed with funding from the Strategic Research and Development Program (SERDP) of the Department of Defense. Novel aspects of MERAF include: (1) the assessment of risks from physical stressors using an ecological risk assessment framework, (2) the consideration of contingent or indirect effects of stressors (e.g., population-level effects that are derived from habitat or hydrological changes), (3) the integration of risks associated with different component activities or stressors, (4) the emphasis on quantitative risk estimates and estimates of uncertainty, and (5) the modularity of design, permitting components of the framework to be used in various military risk assessments that include similar activities. The particular subject of this report is the assessment of ecological risks associated with a testing program at Cibola Range of Yuma Proving Ground, Arizona. The program involves an Apache Longbow helicopter firing Hellfire missiles at moving targets, i.e., M60-A1 tanks. Thus, the three component activities of the Apache-Hellfire test were: (1) helicopter overflight, (2) missile firing, and (3) tracked vehicle movement. The demonstration was limited, to two ecological endpoint entities (i.e., potentially susceptible and valued populations or communities): woody desert wash communities and mule deer populations. The core assessment area is composed of about 126 km{sup 2} between the Chocolate and Middle Mountains. The core time of the program is a three-week period, including fourteen days of activity in August of 2000

Microbe-aliphatic hydrocarbon interactions in soil: implications for biodegradation and bioremediation.

Aliphatic hydrocarbons make up a substantial portion of organic contamination in the terrestrial environment. However, most studies have focussed on the fate and behaviour of aromatic contaminants in soil. Despite structural differences between aromatic and aliphatic hydrocarbons, both classes of contaminants are subject to physicochemical processes, which can affect the degree of loss, sequestration and interaction with soil microflora. Given the nature of hydrocarbon contamination of soils and the importance of bioremediation strategies, understanding the fate and behaviour of aliphatic hydrocarbons is imperative, particularly microbe-contaminant interactions. Biodegradation by microbes is the key removal process of hydrocarbons in soils, which is controlled by hydrocarbon physicochemistry, environmental conditions, bioavailability and the presence of catabolically active microbes. Therefore, the aims of this review are (i) to consider the physicochemical properties of aliphatic hydrocarbons and highlight mechanisms controlling their fate and behaviour in soil; (ii) to discuss the bioavailability and bioaccessibility of aliphatic hydrocarbons in soil, with particular attention being paid to biodegradation, and (iii) to briefly consider bioremediation techniques that may be applied to remove aliphatic hydrocarbons from soil