Evaluation of a Pilot-Scale Constructed Wetland Treatment System for Renovation of a Specific Oilfield Produced Water for Beneficial Use

Oilfield produced waters (OPWs) are brought to the surface when oil reservoirs contained in water-bearing geologic units are extracted. Large volumes of OPW present environmental challenges concerning disposal, as well as potential opportunities for beneficial use if constituents posing risk can be remediated. In this study a pilot-scale constructed wetland treatment system (CWTS) was specifically designed to treat an OPW from sub-Saharan Africa for use in irrigation and livestock watering. Three major objectives were to: characterize and identify constituents of concern in the OPW in terms of beneficial use, evaluate treatment performance of a pilot-scale constructed wetland treatment system for simulated OPW, and conduct seed germination and early growth (SG/EG) bioassays to confirm suitability of post-treatment simulated OPW for irrigation. Through a risk assessment approach incorporating exposure pathways and calculated risk quotients, Fe, Mn, Ni, Zn, and oil and grease were identified as constituents of concern (COCs) in the OPW for irrigation and/or livestock watering. Chemical and biological performance of the pilot-scale CWTS designed for these COCs indicated decreased aqueous concentrations (Fe, Mn, Ni, Zn, and O&G) and decreased toxicity to P. promelas and C. dubia after treatment. SG/EG bioassays demonstrated greater values for early growth response parameters (i.e. root and shoot length and mass) for seeds germinated in post-treatment waters compared to pre-treatment simulated OPW. Combined, the characterization, pilot-scale experiments, and SG/EG bioassays indicate the OPW has a high potential for treatment and beneficial use based on chemical and physical composition, volume, treatment kinetics, and local need for water for irrigation and livestock

Language Disorder Associated with Alzheimer's Dementia, Left Hemisphere Stroke, and Progressive Illness of Uncertain Etiology

TB

Raven's Coloured Progressive Matrices: Interpreting Results Through Analysis of Problem-type and Error-type

TB

Models of Aphasia Treatment in Clinical Aphasiology 1972-1988

TB

Acquisition and Generalization of Cued Speech by a Chronically Aphasic Adult

TB

Repeated Trials of Words by Patients with Neurogenic Phonological Selection - Sequencing Impairment (Apraxia of Speech): Stimulus Mode and Response Condition Revisited

TB

Cost-Effectiveness of Treatments for Aphasia

Significant evidence exists documenting the effectiveness of aphasia treatments. Fewer studies have examined resource utilization, reimbursement, costs, or the cost-effectiveness of aphasia treatments. We add to this literature by analyzing the cost-effectiveness of aphasia interventions that used single subject experimental designs. We analyzed 96 interventions involving individuals with post-stroke aphasia. Cost effectiveness was best in early sessions, about $9 for each 1$75 for each additional percentage point of improvement. Aphasiologists are encouraged to consider the cost-effectiveness of their interventions relative to specific aphasia profiles and well-defined aphasia treatments

Agraphia in Left and Right Hemisphere Stroke and Alzheimer Dementia Patients

TB

Duke Prognosis Profile Worksheet: Inter- and Intraobserver Reliability

TB

Renewable Energy Opportunities at Fort Polk, Louisiana

This document provides an overview of renewable resource potential at Fort Polk, based primarily upon analysis of secondary data sources supplemented with limited on-site evaluations. This effort focuses on grid-connected generation of electricity from renewable energy sources and also on ground source heat pumps for heating and cooling buildings. The effort was funded by the U.S. Army Installation Management Command (IMCOM) as follow-on to the 2005 Department of Defense (DoD) Renewables Assessment. The site visit to Fort Polk took place on February 16, 2010