The Board of Education Building Project for Frederick County Public Schools was a design/build that consists of approximately 90,000SF and five-stories. The structure was built with cast-in-place concrete columns and walls with post-tensioned slabs on a caisson foundation system. The site (known as Site G) is located in known Karst geology, specifically the Lime Kiln member of the Frederick Formation. Approximately 5-feet of uncontrolled fill were found on the site with residual soils and limestone rock beneath the fill.
Environmental Consulting Services provided by Specialized Engineering consisted of a Phase 1 Environmental Site Assessment (ESA) and Phase 2 ESA where several concerns were studied. Additional sampling and testing was provided to establish a grid for determining the extent of contaminated vs. non-contaminated soils. Results indicated soils onsite were contaminated with traces of lead, arsenic, and Total Petroleum Hydrocarbons (TPH). Consulting and monitoring services were provided under the Brownfield Voluntary Cleanup Program that the City of Frederick entered into through the Maryland Department of the Environment (MDE). In addition, a Remedial Action Plan (RAP) was provided. Removal of contaminated soils was supervised by Specialized Engineering per MDE regulations and the RAP recommendations.
The Geotechnical Engineering Services provided were separated into three phases. In total, services included the performance of a subsurface investigation through the drilling of 12 soil borings, an electrical resistivity (ER) survey, and an air track study. Three borings contained rock cores. The rock cores varied from very poor to excellent. Three monitoring wells were also installed. As a result of the ER survey, possible soil-filled and air-filled voids were located at multiple locations. Air-track drilling was conducted in select locations where possible voids were previously identified.
Field Quality Assurance/Quality Control Services included the monitoring and tracking of fill materials in accordance with the MDE agreement with the City of Frederick and project documents. Also, subsurface interpretation of rock suitability; review of laboratory data for soil analysis and construction suitability in embankments; testing and inspection of soil compaction, rebar, cast-in-place concrete, caissons, mortar and grout, structural steel, light gauge metal, post-tensioning tendons; and providing engineering analysis and design recommendations during construction for any specific site conditions that require such services.
Laboratory Testing & Analysis Services included that of proposed structural fill and utility backfill materials, cast-in-place concrete cylinders, and structural masonry mortar and grout. Wish to learn more about our involvement with this project? Please contact us at 800-773-3808.