Power plant decommissioning

Bluegrass has performed reactor vessel cutting and steam generator replacements at Sequoyah, Watts Bar, Browns Ferry, Waterford Nuclear Generating Station, Connecticut Yankee, Humboldt Bay, and Big Rock Point Nuclear power plants over the course of the last 30 years.^[6]

Plutonium Immobilization Project

The company has worked for the government of the United States of America: Department of energy on their Plutonium Immobilization Project, "After the low pour rate and instrumented canisters cooled, Bluegrass Bit, Inc. used a diamond wire saw to section them at four heights. The sections were then studied for evidence of hardware deformation and glass voids."^[4] This project focused on the finding a way to disposition excess plutonium of a weapons grade classification.

Diamond shaving of contaminated concrete surfaces

The company helped to test using diamond shaving to decontaminate radioactive surfaces.^[7]

Tokamak Fusion Test Reactor (TFTR)

In 1997, Bluegrass with the help of the Princeton Physics Laboratory offered a demonstration of how the TFTR could be disassembled with diamond wire sawing, "Based upon the demonstration at PPPL on the TFTR surrogate, the diamond wire cutting technology is superior to the baseline technology for both cost and safety considerations. The combination of void filling with this cutting technology will significantly reduce personnel radiation exposure through shielding, remote operation (normal application of this technology), and radionuclide stabilization".^[8][9]

ITER

In 2018, Bluegrass supported General Atomics by cutting a 1⁄4 scale mockup of the ITER^[10] solenoid constructed by wrapping 288 individual stainless steel bars with copper conductor and coiling the resulting "superconductor" into a ring 3 ft tall x 2 1⁄2 ft wide. The heart of the ITER tokamak, a solenoid is used to magnetically confine a plasma of reactive charged particles into a hollow doughnut-shaped container. The ring of stainless steel and copper was segmented into 4 pieces sized for shipment to another facility for analysis.

NS Savannah

Retired NS (Nuclear Ship) Savannah,^[11] anchored at Baltimore, MD, underwent a renovation in 2018 which required cutting into the nuclear containment vessel to gain access to the reactor. Bluegrass engineered and fabricated bespoke equipment for the confined space to cut, lift and move the 2 ton containment wall cut blocks. The removal of the cut segments had to all be done in a very confined space mostly by manual labor and an elaborate pulley system designed specifically for this job alone.

Transportation: highways, railroads, ports, bridges

Railway bridge projects include a Union Pacific Railroad over the Willamette River in Oregon, and a BNSF pivot bridge over Bayou des Allemandes. Highway bridge projects include the Dumbarton Bridge in California and Wisner Boulevard bridge^[12] in New Orleans, LA. At the Port of Los Angeles, CA, an underwater wire saw cut Berth 29 for removal. On the demolition of the East Span of the San Francisco-Oakland Bay Bridge^[13] in Spring 2017, Bluegrass cut and segmented the above-water blocks of Piers E6, E7, E8, and E10 through E16, then core drilled for rigging and removal all the cut blocks except those on E6. The pier demolition project was authorized by the San Francisco Bay Conservation and Development Commission^[14] in part to mitigate for all the fill associated with construction of the new East Span of the Bay Bridge.

Hydroelectric

Bluegrass Slot Cut at Hiwassee Dam

Projects such as Hiwassee Dam^[15] and Fontana Dam^[16] have been a focus of the company as well, also see their work with Tennessee Valley Authority.^[17] With regard to dam remediation and upgrades, slot cutting projects are the company's main focus. It is akin to slicing a concrete dam like a piece of birthday cake. The technique is simple but very difficult, rotate a loop of cable strung with diamond embedded beads through the structure — essentially, like using a loop of fishing line to cut a cake. Slot cutting is employed to create expansion joints in dams afflicted with compression stresses due to concrete swelling. Alkali Aggregate Reaction, or AAR, is a chemical reaction in concrete created where the aggregate has a high silicon dioxide content. The southeast USA is one such region, and dams in that area require periodic slot cuts to avoid cracking, leakage, and interference with mechanical components such as gates and turbines. The time intervals depend on the AAR specifics of each structure, but 10 years is an average.

Bluegrass participated in the Saluda Dam Remediation project in South Carolina, a requirement by the Federal Energy Regulatory Commission which involved seismic upgrades to the dam and building a backup dam immediately downstream. Bluegrass was contracted to assist with removal of concrete piers and retaining wall to provide access to the penstock towers which supply water to the turbines in the hydroelectric plant. Bluegrass diamond wire saws were ideally suited to the job because of the minimal vibration emitted, therefore avoided the potential hazard of vibrating debris into the draft tubes. Expansive grout and robotic hammers were also used to break the concrete blocks for removal.

NASA

Cell B&C are demolished to make room for new SLS tooling.

As part of planning the Orion programme for the journey beyond low Earth orbit to destinations such as Mars, NASA needed to demolish the existing concrete silos (built to assemble the Space Shuttle booster rockets) at their Michoud Assembly Facility. This was necessary in order to replace the silos with larger Space Launch System (SLS) core stage assembly towers. The task of removing the existing concrete silos was estimated to take three months. Bluegrass was called in to regain schedule for the overall project, eventually completing the demolition of cells B and C in a month.^[18][19]

U.S. Patent #8,286,625

Bluegrass Underwater Saw

The patent^[3] was filed with the advantages being summarized as follows:

1. An advantage of the present invention is a diamond wire saw assembly that provides the ability to cut large diameter heavy walled multi-string pipes remotely, safely and quickly.
2. Another advantage is a diamond wire saw assembly that eliminates labor-intensive methods requiring the use of divers at extreme depths.
3. Another advantage is that the diamond wire saw assembly can be deployed by remotely operated vehicles.
4. Another advantage is that the diamond wire saw assembly can be used for removal of damaged offshore oil platforms as well as for decommissioning of oil platforms that have reached their useful life and are being removed.
5. Another advantage is a diamond wire saw assembly that is portable.
6. Another advantage is a diamond wire saw that eliminates wire breakage.

Hurricane remediation

Bluegrass was involved in the arduous post-Katrina and -Rita cleanup of toppled or damaged offshore production platforms. Operating from work vessels chartered by Chevron, the cleanup team moved from platform to platform in the Gulf of Mexico, cutting structural platform members, stringers and caissons underwater and on deck to comply with BOEM and BSEE federal requirements to remove O & G (Oil and Gas) production debris from the seafloor.

Paper mills

The production of wood pulp and paper products requires extensive concrete structures including foundations, walls, raised platforms and kilns. Refractory in kilns needs to be replaced periodically. A variety of maintenance, upgrade, retrofit, and replacement projects in this industry calls into service the full array of demolition equipment: core drills and diamond wire saws for cutting concrete bases, walls and foundations, and for releasing and cutting tanks and chests. Robotic hammers are able to work in the limited space of kilns to effectively break refractory and lime buildup for removal.

Chemical plants and refineries

The structures, mechanisms and environments of chemical plants and refineries are ideal candidates for the spark-free and vibration-free concrete and metal cutting technologies used by Bluegrass.