The WTP is being constructed and commissioned to process and stabilise nearly 60 million gallons of radioactive and chemical waste from plutonium production efforts from World War II and the Cold War period. Construction began on the project in 2001 and is scheduled to continue well into the next decade, with several commissioning phases for the various project facilities. The Applus+ contract is to provide CMT support for the remaining 260,000+ cubic yards of concrete and nearly one million linear feet (about 190 miles) of underground piping that has to be backfilled with engineered soil and compacted to specification in order to support above-ground facilities and ancillary structures.
Several challenges had to be overcome to satisfy the client’s 30-day window scheduled for a seamless turnover from the previous CMT subcontractor to Applus+. These challenges included: complete staffing of the project with management, technical and administrative personnel; site-specific training for personnel for a full week; and calibration, acceptance, and identification of over 300 pieces of Materials and Testing Equipment (M&TE) in the laboratory facilities on-site. The most significant challenge was the fact that Applus+ CMT procedures and forms needed to be submitted and approved by the client before the work was carried out. This was complicated by the fact that the project’s specifications cited standards in place at the time the plan was initially conceived, while Applus+ keeps its procedures and forms abreast of the latest versions of standard requirements (e.g. American Society for Testing and Materials (ASTM)).
The project objective was complex, with hundreds of miles of piping, including lines for loading to dock, truck and rail, and internal piping to facilitate product storage, movement, blending and storage tank circulation. Marine terminals have constant traffic from ocean-going tankers, in addition to mixed-mode transport activity of rail, truck, storage and pipelines. Given the terminal’s proximity to the marine environment, preventing an incident or leak was the client’s top priority. Also key was assuring system reliability, which would provide the client with a competitive advantage by reducing the unloading time for each tanker, truck or railcar in the facility.
Very early in the project, it was decided that an internal inspection technique was preferable to an iterative external evaluation. This was in light of the time-consuming and expensive process of removing and reapplying insulation, attempting to screen affected areas, and assessing pipe conditions using external non-destructive methods in hard-to-access locations. DTI Trekscan (an ultra-high resolution ultrasonic inspection solution) was the chosen technology, as it provides 100% overlapping inspection of the pipe’s internal and external wall. It also has the versatility needed for on-time assessment, given the limited line access and design challenges of the client’s system.
The initial inspection run was completed in water, using a third-party contractor for pumping, storage and water management services. Due to a prolonged mechanical pipeline cleaning process, the water management expense caused budget overruns and jeopardised the project schedule. Working with the client, Applus+ was able to take advantage of the lightweight design, low drag and low-flow design capability of DTI Trekscan, using an on-site fire hydrant as the propulsion source. All subsequent runs have used hydrant water, providing significant time and cost savings.
During subsequent runs, Applus+ maximised the effectiveness of each DTI inspection by combining multiple pipe segments in a single inspection, using a temporary industrial hose to loop the segments. This was a first for DTI Trekscan and provided significant value to the client in terms of cost, time and efficiency of each launch.