WSP Contaminated Lands and Geo-sciences SOQ

Contaminated Lands and Geo-sciences | SOQ

PLANT GORGAS ASH POND CLOSURE Birmingham, Alabama

The Gorgas Ash Pond closure project is a large and complex CCR clo sure project. The site is a historic wet sluiced (~ 400 acres) ash pond with greater than 22 M CY of CCR at deposit thicknesses of over 140 feet deep. The project includes a hybrid closure design combining removal of CCRs from more sensitive areas near adjacent rivers and consolidation and per manent capping of the CCR materials on-site. The Gorgas closure solution incorporates an innovative application of dredging to a paste thickening plant for material handling and placement to significantly increase pro duction and safety. WSP was retained to provide engineering services for the closure. Ser vices included closure options assessments, permitting support, geotech nical assessment (including detailed in-pond investigation and material characterization), construction instrumentation and monitoring plan, groundwater modeling and site CSM development, beneficial use testing/ mapping and landfill engineering that included hydrology and hydraulics, geotechnical engineering (including seismic, slope stability and seepage assessment), dam engineering (including a new RCC attenuation dam), construction phasing, and engineering support during construction.

27