In-situ bioremediation of amine- and glycol-contaminated soils using low-intervention methods

Biological plugs are an innovative, low-intervention, in-situ bioremediation methodology for both saturated and unsaturated contaminated soils. They are modular in-ground immobilized microbe bioreactors designed to rapidly increase the oxidation of organic contaminants by placing an adapted consortia of microorganisms in close proximity to the contaminants of concern. The approach is versatile, in that contaminants can be remediated in-situ without the removal of existing structures as well as being able to efficiently and economically treat contaminants over a large area. Amine- and glycol-contaminated soils at gas sweetening plants, represent a significant problem in magnitude, prevalence, and risk along pipelines stretching through Canada's western provinces. A field pilot study was conducted at an isolated former gas sweetening plant in northwestern Alberta. Monoethyamine (MEA) and several glycols were successfully remediated in situ in a 138-day time frame. Soil toxicity was significantly reduced. The engineering challenges and associated economics of remediating such isolated sites are also presented.     

Limiting the environmental impact of animal production odors

Odors emananting from animal production facilities are the primary environmental cause for complaint resulting in great corrective expense and, in many instances, facility closure. The current state-of-the-art of odor control technology ranges from intensive waste management and good housekeeping practices to chemical treatment and facility isolation. These controls at best only limit the generation and/or quality of animal production odors. The most effective odor limiting technologies are the most cost intensive. Therefore, methods used are dependent upon the seriousness of the situation and the cost-benefit that may be derived from their use.Original facility design and site selection consideration are of great importance to the existence of confined animal feeding enterprises with a non-farm population which is encroaching at increasing rates into rural areas. Land use planning and zoning restrictions for agricultural/animal feeding purposes may well be the ultimate odor control tool of the future for newly instituted facilities. Extensive basic and applied research is required to provide adequate technology for use by existing facilities.     

Scales of justice: Is there a geographic bias in environmental equity analysis?

Many empirical environmental justice (EJ) studies lack a systematic framework in which to undertake research and interpret results. This paper characterizes the conventional EJ study and examines how results can be influenced by the choice of the spatial scale and scope of analysis. After thoroughly reviewing a sample of prominent EJ studies, a conventional EJ study was performed for (Superfund) National Priorities List sites at multiple scales and scopes. It was found that evidence of environmental injustice could be sensitive to scale and scope chosen, which partly explains the observed inconsistency in the empirical literature. Implications for interpreting existing EJ research and conducting future EJ research are discussed.     

REGIONAL PLANNING FOR LAND DISPOSAL OF WASTEWATER1

ABSTRACT This paper describes the development and use of a mixed integer programming model for the planning of land disposal wastewater treatment facilities. Consideration is given to relevant construction and operating costs for land sites, transmission arteries, land acquisition costs, tangible benefits from land use, controls on aquifers, and various other engineering and technical constraints The model is used to determine which land disposal sites should serve which treatment plants, when initial construction should be initiated and completed, and when capacity expansion should occur. The model's application to the St. Louis Standard Metropolitan Statistical Area is illustrated and discussed.     

Application of the Braun-Blanquet cover-abundance scale for vegetation analysis in land development studies

To document environmental impact predictions for land development, as required by United States government regulatory agencies, vegetation studies are conducted using a variety of methods. Density measurement (stem counts) is one method that is frequently used. However, density measurement of shrub and herbaceous vegetation is time-consuming and costly. As an alternative, the Braun-Blanquet cover-abundance scale was used to analyze vegetation in several ecological studies. Results from one of these studies show that the Braun-Blanquet method requires only one third to one fifth the field time required for the density method. Furthermore, cover-abundance ratings are better suited than density values to elucidate graphically species-environment relationships. For extensive surveys this method provides sufficiently accurate baseline data to allow environmental impact assessment as required by regulatory agencies.     

PHYSICAL PROCESSES AND EUTROPHICATION1

ABSTRACT: Biological responses to physical-chemical processes were examined in Toronto and Hamilton Harbours of Lake Ontario. Nutrient loadings to the harbors are large and are of similar magnitude, yet the trophic conditions of the harbors were considerably different. Lake oscillations were found to determine the flushing rates and environmental stability of the harbors. LOW residence times (<10 days) resulted in homogenous chemical conditions in Toronto Harbour, and prevented the establishment of large phytoplankton crops. The longer retention time of Hamilton Harbour permitted the establishment of huger phytoplankton crops. There probably exists a critical retention time where nutrient input events persist for a sufficient period of time for the algal community to adapt to and exploit the environmental conditions of nearshore areas.     

ENVIRONMENTAL FEATURES FOR FLOOD CONTROL CHANNELS1

ABSTRACT: The environmental effects of flood control channel modifications such as clearing and snagging, straightening, enlargement, and/or paving can be quite severe in some cases. Information review reveals that several environmental features have been incorporated into the design, construction, operation, or maintenance of recent flood control channel projects to avoid adverse environmental impacts and enhance environmental quality. Typically, these features have been proposed by conservation agencies and designed with minimal quantitative analysis. Environmental features for channel projects include selective clearing and snagging techniques, channel designs with nonuniform geometry such as single bank modification and floodways, restoration and enhancement of aquatic habitat, improved techniques for placement of excavated material, and revegetation.