Featured Projects

At FPL’s St. Lucie Nuclear Power Plant in the late stages of an outage for one of the nuclear power generating units it was discovered that existing carbon steel pipes for the cooling water discharges had become corroded and required replacement via an “emergency response” mode. Dunkelberger was retained by UESI as a member of the design-build team to provide geotechnical services involving exploratory work (subsurface investigation) and construction support (monitoring and testing).

As part of the pre-construction services, Dunkelberger used the gathered subsurface data to formulate geotechnical criteria for support (bedding) of the new piping and also for stability of temporary sheetpile walls.

During construction, Dunkelberger provided round-the-clock (24/7) geophysical (ground vibration) monitoring of sheetpile driving and soil compaction activities. Since regulatory restrictions prevented soil samples leaving the Plant, Dunkelberger established an on-site laboratory for soil gradation and Proctor tests. Dunkelberger’s quality control testing covered pipe backfill placement and structural concrete for the headwall.

The project was completed in 60 days.

During utility installation work, the contractor discovered a large, buried (latent) deposit of trash-like debris within the roadway right-of-way. Sarasota County engaged Dunkelberger, under its continuing services contract, for fast-track exploratory work and geotechnical engineering evaluation of options for removal and disposal of the debris. Dunkelberger recommended a partial removal option, coupled with geosynthetic reinforcement of the pavement section, that saved the County $200,000 in debris disposal costs. Dunkelberger’s quick response, and practical engineering recommendations, minimized construction delays.

As part of the engineering evaluation, Dunkelberger completed an environmental assessment of potential contaminants in both soil and groundwater in the area of the debris deposit. The Florida Department of Environmental Protection (FDEP) approved Dunkelberger’s assessment allowing the partial removal option to be implemented and without delay.

Construction of the alternate pavement section, with geosynthetic installation, was field inspected and tested by certified (CTQP) engineering technicians from Dunkelberger.

Dunkelberger was retained as a geotechnical sub-consultant as part of the design effort to prepare preliminary plans and specifications for bidding by design-build vendors. `

Subsurface data in the planned facility area was collected on a fast-track basis using multiple drilling crews from Dunkelberger to complete deep test borings. The data was incorporated into a Baseline Geotechnical Report that included preliminary design criteria for structure foundations, both shallow and deep alternatives, slabs, retaining walls, and pavements.

Under a separate services authorization, Dunkelberger prepared earthwork specifications for backfilling of a large, existing lake within part of the planned facility area. Subsequently, Dunkelberger carried out a quality control (QC) program involving field oversight and testing, including the monitoring of piezometer and settlement plate installations, during the lake backfilling and surcharging.