This project involved the Site Grading and Utilities (Water, Storm Drainage and Sanitary Sewer)
on two sites at the BWXT Y-12 Oak Ridge Facility. The work performed included site preparation,
installation of erosion control, temporary site fencing, and utilization of best management practices;
sitework demolition including existing fencing, asphaltic pavement, and concrete pads; mass site
grading for buildings, roadways and ramps; relocation and reconnection of existing primary and
secondary utilities; installation of domestic water lines, deep sanitary sewer lines, deep storm
sewer lines, and manholes and cleanouts; installation of fire distribution line and system;
backfilling of utilities and structures; installation of a deep sanitary sewer line and structures
in a highly secured area; stone base and asphalt pavement; permanent fencing and seeding.
Avisco, Inc. was awarded a contract to construct a new 5.5 mile haul road from ETTP to the Environmental Management Waste Management Facility (EMWMF) near the Y-12 Security Complex to facilitate the Department of Energy’s Accelerated Clean-up Program (ACP). The haul road provides a dedicated means of travel between cleanup efforts at East Tennessee Technology Park and EMWMF without the need to use public roads.
The overall scope of work included furnishing and installing erosion and sediment controls; traffic control; installation of storm drainage and structures; clearing, grubbing, and grinding of the vegetative debris within the roadway construction limits as well as wetland areas; topsoil stripping and replacement; undercutting and backfilling unsuitable soil areas; performing on site excavations and embankments; loading, hauling, and placing borrow material; fine grading; construction of four bridge approaches and a mid-bridge support island; support for mechanically stabilized earthen walls; specialty seeding and mulching; and site restoration.
Avisco, Inc. was awarded a contract by BWXT Y-12 to perform the initial site preparation, mass excavation and grading on the initial phase of the Y-12 National Security Complex’s new uranium storage facility, the Highly Enriched Uranium Materials Facility (HEUMF). As part of Y-12 National Security Complex’s modernization plan, Avisco’s overall scope of work on the HEUMF project consisted of excavation and shoring; installation of subsurface utility sleeves; grading; hauling spoils and asphalt; vegetation removal; site preparation for the hollow fill area, asphalt laydown area and road modification; asphalt grinding and stockpiling; removal of underground utilities including mechanical, electrical, catch basins, storm drain piping, duct banks and conduit; removal of above ground facilities including curbs, gutter, sidewalks, pavement, concrete pads and pedestrian crossings; installation of temporary construction roads and site entrances, temporary site barriers, temporary site fencing, temporary site drainage facilities, temporary silt fencing, new underground piping utilities, catch basins, manholes, concrete, forms, and shoring; soil and aggregate backfill.
Avisco, Inc. was contracted through Heery International, Inc. to perform the initial site preparation, mass excavation and grading for the initial phase of construction on the Tennessee Office Building located on the U.S. Department of Energy’s Oak Ridge National Laboratory (ORNL) campus in Oak Ridge, Tennessee. As part of ORNL’s modernization plan and through an innovative public-private partnership, UT-Battelle, LLC selected Colliers Keenan and Heery International, Inc. to design and construct the Tennessee Office Building for future ORNL occupancy. Avisco’s overall scope of work included clearing and grubbing, installation of erosion control, mass grading and excavation, rock blasting and rock removal, and installation of storm drainage and structures for the preparation of the Tennessee Office Building site.
Spallation Neutron Source Conventional Facilities - The U.S. Department of Energy (DOE) Office of Science has funded the construction of a new, accelerator-based neutron source, the Spallation Neutron Source (SNS), which will provide the most intense pulsed neutron beams in the world for scientific research and industrial development.
Initial Site Preparation and Mass Excavation - Avisco performed the initial site preparation, mass excavation and grading for the SNS facilities located at the U.S. Department of Energy's Oak Ridge National Laboratory in Oak Ridge, Tennessee. The work consisted of mass excavation and erosion control features on approximately 46 acres. The site mass grading activities included: erosion control, backfill and seeding of disturbed areas, stockpiling, grading, excavating, clearing and grubbing and the installation of storm drainage piping, structures and base stone. Other activities included the construction of a gravel pad for a temporary AE/CM trailer complex and the construction of temporary site roads, drainage and parking areas.
Avisco, Inc. was contracted to design and construct a structural concrete wall with tie-back anchorage to support the slope below a 4 million gallon water storage tank. Avisco performed the initial site preparation and construction of a work bench. Nicholson Construction Company, under subcontract to Avisco, designed and constructed the wall. Avisco worked in parallel with Nicholson to excavate the bench and restore the site. The wall consisted of drilling thirty caissons to depths of 30 feet. Each caisson (42 inches in diameter) serves to form the reinforced concrete soldier beam set 10 feet into underlying shale rock Residuum. As the caissons were completed, Avisco excavated the work bench in 6 ft. lifts and Nicholson placed shotcrete lagging to support the exposed soil. This was followed by installation of tie-back anchors, tensioning, and excavation to the next row of anchors. A reinforced concrete wall was constructed along the face of the soldier beams. The wall was designed for seismic loading typical for the area.
Avisco, Inc. flattened unstable slopes and excavated for massive thrust blocks, pier footings and the approaches for a pre-cast, post-tensioned, triple-arch bridge, the first of its kind in Tennessee and the largest in the United States. Other activities included a parking area, curbs, gutters, sidewalks, pedestrian overlook, approaches on each end of the bridge, stone masonry facade, erosion control, seeding and mulching, ditch paving, and riprap.
Avisco constructed one of the most state-of-the-art concrete storage pads for radioactive waste known today. In order to build this monolithic pad 60 feet by 90 feet and 15 inches thick. There were approximately 50 tons of epoxy-coated steel and 300 cubic yards of concrete required to build the pad. Embedded in the concrete was a network of strain gages so that constant monitoring could be conducted in the future as loading occurred. This pad also had a built-in spill containment system. If a spill occurred, it flowed by gravity to a collection tank for holding and processing. Grades were critical for this pad since concrete was required to have a certain thickness above and below the reinforcing steel. Safety and health was of primary importance since the work was being done in the solid waste storage area and near existing containers. The work was completed on time.