Underwater Construction Corporation (UCC) completed the installation of a fish barrier net for a large hydroelectric facility located in Missouri. This net was located upstream from the dam and enclosed the powerhouse to restrict the aquatic life from entering the generating turbines of the facility.

The scale of the project required the use of equipment and material barges. These barges facilitated enough space to allow for a complete deep water dive package, a 70 ton crane and enough area to hold all materials for each task of the project. Each barge was manipulated with the use of push boats along with a hydraulic driven anchor system to stabilize the platform on location while work above as well as in water was being performed.

The deep water dive package included UCC’s own decompression chamber system and all other equipment required to successfully run multiple air and mixed gas (NITROX) dive operations. This specialized equipment on-site allows the UCC dive team to be self-sufficient during the length of the project while successfully completing more than 170 dives including planned surface decompression dive profiles to depths greater than 100 ft. The use of mixed gas and surface decompression allowed for extended bottom time for the divers meaning more production and less down time for the project.  Along with the equipment, UCC provided a complete dive crew proficient in the use of mixed gas and decompression procedures including our own deep dive specialist to oversee all operations.

The net anchoring system consisted of large concrete blocks averaging in size from 2-6 tons per piece. This system was made up of both lower net anchors (21) and tie back anchors (13) that are designed to conform to the original configuration of the barrier. The crane barge was used to set these blocks remotely with a hydraulic release which was operated from surface or with diver’s assistance.  In order to guarantee the correct location of each anchor, HYPAC hydrographic software was used. Using this software, UCC was able to position each block within an average of one foot or less to the planned location in as much as 110 feet of water.

During the first stage of the project, UCC’s dive team completed all structural work as well as the remote setting of all concrete anchors for the barrier net. During the second stage of the project, UCC’s dive team completed the initial anchor connections for the 900 foot net within two working days. The remaining tie backs, debris netting and final project inspections were completed shortly thereafter with the use of UCC’s two dive skiffs. All connections and hardware were verified and documented per specifications and planned drawings.

UCC’s expert project team worked closely with site engineers, key facility personnel and UCC’s approved network of vendors to design and manufacture the new log boom and barrier net system. UCC presented the new project drawing and net mock-up samples to the owners of the facility for evaluation. UCC’s work plans, project schedule and drawings were approved and the project was successfully completed over the summer of 2011. As a result of careful planning UCC divers and crew were able to complete the project under budget, ahead of schedule and with zero safety incidents.

UCC was further contracted to perform repairs to the structure starting with the removal of the damaged areas while final repair drawings were being developed. The work began by cutting the material using underwater cutting torches (BROCO) and a variety of pneumatic and hydraulic grinders.

After repair drawings were issued, UCC ordered the necessary materials per engineering requirements via a fabrication company that completed the fabricating prior to being loaded and shipped to the work location. Once on site, UCC divers would rig and crane into place each piece per the drawings. When field modifications needed to be performed UCC would describe those modifications to the engineers who developed changes. The field modifications were done by qualified UCC personnel on site to alleviate any delays. All work was completed using UCC procedure qualified underwater and top side welders. Six (6) certified underwater welders were required for the project using AWS D3.6 and D1.1 all position groove welds with certified underwater welding electrode. In addition, UCC provided two (2) certified level II underwater welding QC personnel to perform inspections and document the work being performed while the project was progressing. UCC’s welding and QC programs were reviewed and accepted by the customer. The project was completed under budget and with zero safety incidents.

Services, Limited’s NW UK facility at Beckermet Technology Park, Nr Sellafield, Cumbria, UK. Underwater Construction Corporation (UCC) was in attendance as a showcase exhibitor and onsite demonstrator. UCC and Thin Film Technology, Inc. conducted live in-water diving operations in the presence of more than 600 nuclear industry attendees that demonstrated the application of UCC’s Advanced Underwater Coating System.

The two day event showcased TFT’s underwater nuclear coatings product which was applied using a revolutionary application system pioneered by UCC’s underwater research and testing facility. This same process has been used by UCC to successfully apply TFT underwater coatings to carbon steel, stainless steel, and concrete surfaces throughout nuclear facilities around the world for more than 15 years.

The four person UCC team was led by Philip McDermott, UCC’s Director, of Global Nuclear Services. The live diving demonstrations showcased not only TFT’s underwater coating product but also UCC’s continued global leadership in nuclear diving.

UCC’s unique large area application method is invaluable to the nuclear power industry as it allows for the application of the TFT coatings without building staging and dewatering. The use of divers also greatly reduces possible contamination and radiation exposure to the workforce.

The annual Waste Management (WM) Conference, presented by WM Symposia (WMS), is widely regarded as the premier international conference for the management of radioactive material and related topics. WMS is a non-profit organization dedicated to education and opportunity in waste management. It was founded to provide a forum for discussing and seeking cost-effective and environmentally responsible solutions to the safe management and disposition of radioactive waste and radioactive materials.

The annual WM2010 conference attracted over 2,000 registrants from throughout the world and provided significant opportunities for networking, professional growth and education – as well as business opportunities. This conference was attended by decision makers, project managers, and technical and procurement specialists representing the government and private organizations undertaking the global tasks of radioactive material management, decommissioning and site remediation.

WM2011, the conference’s 37th year, is expected to attract representatives from over 35 countries, presenting more than 400 papers in over 80 technical sessions.  WM2011 will be held February 27 – March 3, 2011 at the Phoenix Convention Center’s West Building. The published deadline for abstracts is August 13, 2010 and the Program Advisory Committee will review abstracts in Phoenix on September 13, 2010.

Sponsoring organizations include the American Nuclear Society (ANS), the American Society of Mechanical Engineers (ASME) and the Organization for Economic Co-operation and Development / Nuclear Energy Agency (OECD/NEA).  The conference is also organized in cooperation with the US DOE, the Nuclear Regulatory Commission (NRC), the Environmental Protection Agency (EPA) and the International Atomic Energy Agency (IAEA).

For more information visit their website: http://www.wmsym.org

We look forward to seeing you at WM 2011.

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Underwater Construction Corporation
Midwest Division
5601 S. Pennsylvania Ave
Cudahy, Wisconsin 53110
877-717-DIVE