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Biomedical subjects

C Woolard

Publications and source records attributed to C Woolard.

3 recordsLinked to original sources

Laboratory model of a petroleum migration barrier in arctic alaska

Child's Pad is a gravel construction pad that was contaminated with petroleum during oil-field service operations in Deadhorse, AK. As part of a remedial action plan, a buffer strip of uncontaminated sandy gravel was placed along certain sections of the pad boundary. A peroxygen formulation manufactured by Regenesis Copyright, sold as Oxygen Release Compound (ORC(R)), was placed in the buffer strips. The ORC was intended to supply oxygen to aerobic microorganisms capable of degrading petroleum. Tests were conducted in a 1/2 scale laboratory cell to determine the oxygen release characteristics of the ORC when subjected to expected subsurface flow rates of up to 0. 02 l/s (6.9 m/day). In laboratory tests, a zone of enhanced oxygen concentration was formed down-gradient from the ORC socks. Only during periods when the flow rate was less than 0.01-0.015 l/s (3. 5-5.2 m/day) was ORC-oxygen observed at monitoring points up-gradient or directly cross-gradient of the ORC. Conclusions from the laboratory study were that ORC may provide an aerobic zone in the Child's Pad barrier as far as 1 m directly down-gradient of the sock during periods of high flows (6.9 m/day). Copyright 1999 Elsevier Science B.V.

Journal Article↗

Oxygen release kinetics from solid phase oxygen in Arctic Alaska.

Child's Pad is a gravel construction surface that was contaminated with petroleum during oil-field service operations in Deadhorse, Alaska. As part of a remedial action plan, a buffer strip of uncontaminated sandy gravel was placed along sections of the pad boundary. A magnesium peroxide formulation manufactured by Regenesis, and sold as Oxygen Release Compound (ORC), was placed in the buffer strips. The ORC was intended to supply oxygen to aerobic microorganisms capable of degrading petroleum. Studies were conducted in the laboratory to determine initial oxygen release kinetics from ORC in contact with barrier soil. Studies quantified the biotic and abiotic catalytic mechanisms for converting hydrogen peroxide (a possible MgO2 intermediate) and ORC to oxygen and water, the effects of temperature on oxygen release from ORC, and the effect of field exposure on ORC viability. Barrier soil exhibited sufficient catalytic activity to convert hydrogen peroxide to oxygen faster than the expected biological demand. The oxygen evolution rate (OER) from ORC was lower at 7 degrees C than 21 degrees C by more than two times. The ORC recovered from Child's Pad after less than 1 year retained nearly all of the original available oxygen, although physical bridging was evident.

Alaska↗

Collaborative working with specific speech & language disorder in mainstream education.

Children with specific speech and language disorders are part of a special needs population whose educational and therapeutic needs have been provided for in a variety of settings over the last fifty years. Changes have been implemented in response to a range of legislation. This has also had implications for the delivery and type of provision of the children's education and therapy. The National Health Service and local education authorities (LEAs) have had to respond to legislation and continue to provide for the full range of specific speech and language disorders. This paper will outline how therapeutic input has had to adapt to the changing educational context. Changes in delivery have necessitated a redefinement of roles and adjustments in collaborative working.

Child↗