OWNER:
Kerr McGee Chemical Corporation
Mobile Facility, Theodore, Alabama
ENGINEER:
Thompson Engineering Testing, Inc.
3707 Cottage Hill Road
Mobile, Alabama 36606
In
order to increase their on-site storage capacity for the iron oxide
by-product produced by the plant, Kerr-McGee built a twenty-seven
acre iron oxide containment pond in 1990. The containment dike was
constructed to a height of 22.5 feet with a 15-foot wide crest and
3:1 side slopes for a total length of 3,540 feet. The site was underlain
by soft to very soft marine clays extending from elevation +20 to
elevation -40. Calculations were made to determine the required construction
rate for the dike if the target completion date was met. Using this
rate of construction, effective stress stability analyses were performed
to ascertain the level of reinforcing required to achieve the target
minimum factor of safety at the end of dike construction. Four layers
of uniaxial geogrids were used to achieve this minimum factor of safety.
Instrumentation for the project consisted of settlement plates, slope
inclinometers and piezometers that were monitored during construction.
The project was successfully completed on schedule in 1990.
