Nearing 50% Completion, Vit Plant to Turn Waste into Glass

By Genoa Sibold-Cohn

Hanford - Nearly half the work is done on a $12.2 billion environmental project that will glassify 53 million gallons of radioactive and chemical waste stored on the Hanford Nuclear Reservation near Richland, Wash.

Bechtel National Inc., headquartered in Frederick, Md., is in its eighth year of a $12.2 billion environmental project that will blend tank waste with molten glass and then place it in stainless-steel canisters. This process is known as vitrification, or glassification.

The Department of Energy estimates that one million gallons of radioactive chemicals leaked into the soil and affected groundwater as the result of leaks from 67 of the 177 underground tanks.

Bechtel is actively working on all four main facilities – pretreatment, high-level waste, low-activity and its analytical laboratory. Work also continues at 20 support facilities, including a steam plant, cooler-compressor plant, cooling towers, electrical switchgear buildings, complex underground utilities and waste-transfer piping.

In the pretreatment phase, waste is pumped from the underground storage tanks through a buried pipeline to the pretreatment facility. This is where low-activity radioactive waste and high-level radioactive waste are separated.

Waste identified as low activity goes into a melter preparation vessel where silica and other glass-forming materials are added and the mixture is fed into a melter. Low-activity waste containers are 7 ft tall, 4 ft in diameter and weigh 7 tons.

The mixture is heated to 2,100 degrees and is poured into stainless steel containers.

High-level waste is treated similarly but is poured into stainless steel containers that are 14 ft tall, 2 ft in diameter and weigh more than four tons. Eventually, these containers will be shipped to Yucca Mountain in Nevada for permanent disposal undergound.

The project is 42% complete and is expected to reach 48% by the end of the year, says Drew Slaton, Bechtel’s waste treatment plant communications manager. After a two-year hiatus for seismic considerations, civil and structural work at the high-level waste vitrification and pretreatment facilities resumed this year.

Concrete and structural steel placement are continuing this year at both facilities, and the delivery of the first high-level waste melter, weighing 40 tons, is expected later this year, Slaton says. The facility will have two waste melters. Each melter will produce 3.3 tons of vitrified waste each day, Bechtel estimates.

An 80-ft-tall glass silo was erected onsite in late March, changing the skyline and making progress apparent to visitors. The analytical laboratory is now essentially enclosed and the laboratory emissions stack, an estimated 69 ft tall, should be erected later this year, Slaton says.

There were 3,150 employees working on the project, ranging from construction site workers to engineers. At any given time, there are 150 to 225 job openings for the project.

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Hanford employs roughly 13,000 workers, according to Dean Schau, a regional labor economist based at Columbia Basin College in Pasco. The vitrification project added 1,000 employees within the last year to Hanford’s workforce, Schau adds.

Bechtel is constantly looking for nuclear qualified vendors—fabrication, materials and general construction contractors—who are capable of working to exacting standards and documentation requirements.

Job recruitment has been a challenge for the project because colleges haven’t been producing as many nuclear engineering graduates, and there haven’t been any new nuclear power plants, Slaton says. The last nuclear power plant was built in Tennessee in 1996, the Nuclear Energy Institute reports.

However, there may be a resurgence or as Slaton puts it, a “nuclear renaissance” with foreign countries showing increased interest in using nuclear power for electricity and applications for new nuclear power plants being filed in the United States and domestically.

PNNL Projects to Help Homeland Security Priorities

By Lucy Bodilly and Ryan Ratchford

Pacific Northwest Nuclear Laboratory broke late last year at the Physical Sciences Facility near Hanford. The project will be completed in three phases. Randolph Construction Services, Inc. of Pasco, was awarded a $1.7 million contract last fall for site preparation work that included clearing brush and grading the PSF site, stockpiling soil, excavation, blending and placement of structural fill, and procurement and installation of temporary facilities and utility infrastructure.

In February Apollo Construction, Kennewick, Wash. was awarded a nearly $14-million contract for providing foundations and erecting structural steel for the Physical Sciences Facility project, which is expected to be completed in December 2008. The third and final contract for completing the PSF will be issued in a few weeks. The total estimated cost is over $100 million.

When the foundation is complete and the structural steel is erected on the first of the three buildings, the final contractor will take over and begin work to close-in the structure and install the mechanical, electrical and piping system.

Once complete, the federally-sponsored PSF project will contain scientific research important to U.S. homeland and Department of Energy national security and science agendas.

New construction within the PSF project comprises three main laboratories—Radiation Detection, Ultra-Trace and Materials Science & Technology—as well as a low-level underground lab for ultra-sensitive work and a radiation portal monitoring test track. The track will be used to test technologies that will be deployed along U.S. borders to detect illicit trafficking.

The PSF project is the largest of three planned facilities as part of PNNL's campus expansion. Two other projects will begin later in the year, the Biological Science Facility and Computational Sciences Facility.

Ryan Ratchford, business development representative Apollo Construction Inc., talked a little bit about the project. What is the most difficult thing about the project.

The most difficult thing is getting the project done within the client's budget.

How complicated are the lab spaces?

The radiological lab spaces utilize the same level of complexity as other radiological laboratories. They're comparative to a level 4 bio-laboratory, which Apollo is very familiar with.

What special features do the labs have?

They are radiological labs with bubble tight dampers and HEPA filters. Phoenix valves supply the air and exhaust the air, which provides instantaneous control. What that means is there are two lines coming in, supply and return air, and the Phoenix valves sense the pressure differential. So if the lid of the hood is brought up or brought down, the Phoenix valve instantly reacts and  adjusts. There is always negative pressure and the scientists working on the outside can never get contaminated. That air leaves and goes through a HEPA filter and then leaves the facility through the stacks on the roof.

What special techniques are you using to build the project?

This is a LEED project. Apollo is using 3D modeling to coordinate the entire project. The Lead Building Information Manager (LBIM) will develops 3-D background drawings from electronic copies of the design drawings. The background drawings include structural restraints, interior structures, ceiling construction and elevations. The LBIM will coordinate with the participating contractors to establish system installation zones and system priorities. The LBIM then identifies the conflicts, resolves them and submits the completed coordination drawings for review. The LBIM, CM and the participating contractors will not make changes to the system design in order to resolve any conflicts. Procedures will be established to submit design conflicts to the A/E teams for resolution. The LBIM will also develop document control procedures to incorporate conflict resolution, revisions and owner modifications.