Delivering nuclear safety
Photo by CH2M Hill-Hanford Group
Preparing for Waste Retrieval
More than $1 billion in upgrades are being made to prepare for retrieving Hanford tank waste for treatment.
by Fran DeLozier
Commitment to procedures and process and a reliance on employee innovation transformed this nuclear waste facility into the picture of safety.
a “farm” is usually green, with growing fields and bountiful harvests, but the Hanford tank farm, located just a few miles from the Columbia River in southeastern Washington, cast this traditional picture in a whole different light. The Hanford storage site is home to 177 high-level nuclear waste tanks containing more than 53 million gallons of waste. This “farm” stores 200 million curies, three times that released by Chernobyl. Before 1996, the area was the bane of U.S. Dept. of Energy (DOE) environmental management. One tank would periodically and spontaneously release large quantities of flammable gas. Another tank, without double containment (now required by law), “self-boiled” and required the addition of more than 5,000 gallons of water per month to maintain temperatures within the tank's design parameters. Only a single-wall steel pipe with limited leak detection was available to transfer waste the seven-mile route from the westernmost tank farms to a waste evaporator. The regulators, the public and the U.S. Congress had little confidence that DOE or its contractors knew the chemical, physical or nuclear characteristics of the tanks' contents. In addition, the nuclear safety controls were so complex and varied for different tanks and different operations that few employees understood the hazards or control requirements. In fact, Congress found it necessary to pass a law restricting the operations of more than 50 of the 177 tanks due to safety concerns. These tanks are part of a “watch list.”
U.S. Department of Energy photo
New and Improved
Double-walled tanks under construction at the Hanford site.
The picture at the Hanford site is radically different today, thanks to the CH2M Hill Hanford Group Inc., which manages the waste tanks for the DOE Office of River Protection. Viewing each necessary improvement as a project, the firm attacked specific goals using its Safe Project Delivery business philosophy. One fundamental component of safe project delivery is a sound project management system that includes planning, chartering a team, management and customer endorsement, executing, managing change and closing the project.
Successful projects have included:
Installing consistent flammable gas controls and a new doubly contained transfer line (with redundant leak detection systems) that routinely transports waste.
Emptying the high-heat tank, and installing a new ventilation system to service the doubly contained tanks with the highest heat content.
Putting systems and a plan in place to remove residual pumpable liquids from the noncompliant single-shell tanks by 2004.
Removing more than half of the tanks from the “watch list.” (The rest will be removed by October 2001.)
Developing a comprehensive plan to retrieve the waste, send it to a treatment plant and close the tank farms.
As a result of efforts, the Defense Nuclear Facilities Safety Board, which oversees DOE nuclear safety, has declared that the constituents in more than 78 percent of the tanks have been “characterized.”
Safe Project Delivery at Work
The solution to the problem of a growing “waste crust” in Tank SY-101 provides an example of the safe project delivery philosophy. This million-gallon double-shell tank received national attention in the early 1990s when reactions to radioactive waste inside the tank began to generate flammable gases. The gas became trapped in the waste, and every three months a large amount of gas would vent inside the tank, an event that came to be known as a “burp.” The gases could have ignited during one of these large releases, but in July 1993 the installation of a large mixer pump in the tank allowed small amounts of gas to be released continuously, thereby preventing the larger release and the associated fluctuating waste levels.
Eliminating Risk with Innovation
CH2M Hill Hanford Group largely attributes its successful project management effort to project team innovation. Project managers strive to create an atmosphere that is conducive to high-quality and high-productivity work.
One of the innovations that came out of the SY-101 project was development of a new hose-in-hose waste transfer system. Using the old transfer system for pumping single-shell tanks in 2000, there were three leaks. CH2M Hill employees projected that if something wasn't done, there would be one transfer system leak per year.
Their adaptation of a hose-in-hose system eliminated that risk. The system employs sensors to detect a leak and automatically shut down pumping. The hose also maintains the waste's temperature to help prevent plugs in the line. The innovative transfer system will allow CH2M Hill to finish the project six to 12 months early and cut costs by an estimated $4 million to $5 million.
In another example of innovation, CH2M Hill Hanford Group scientist Bill Zuroff developed a better way to monitor flammable gas during waste tank pumping operations. Extensive maintenance required on the old monitors made them the second leading cause of delays on the project to move liquid waste from Hanford's older single-shell tanks to newer double-shell tanks.
Zuroff contacted a manufacturer and found another flammable gas sensor that could be hooked up to the existing control equipment. Field-testing verified the concept, and three months later, crews began using the sensors as new tanks took over pumping operations.
This solution reduced the time it takes to pump each tank by two to three months, at 1 percent of the cost of using the old monitors. Shortening the pumping time means a significant reduction in risk from a future tank leak and will save more than $2 million.
Hanford at a Glance
The Hanford Nuclear Reservation is a long-term threat to the Columbia River, which is used for power generation, farm irrigation, fishing, transport and recreation. Hanford covers 560 square miles of desert in eastern Washington, along 51 miles of the Columbia River. It is 35 miles north of the Oregon border, and 215 miles upstream from Portland.
History: From 1944 to the late 1980s Hanford produced plutonium for nuclear weapons, using a line of nuclear reactors along the river. Cooling water from the river was piped through the reactors, and then fed back into the river. Spent fuel rods from the reactors were dissolved in nitric acid to separate the plutonium. Enormous amounts of highly radioactive and chemical waste were generated in the process. Since the production of plutonium ceased, Hanford's only mission has been cleanup.
Waste tanks: About 54 million gallons of high-level radioactive and chemical waste are stored in 177 underground tanks the size of three-story buildings and buried in Hanford's central area about 12 miles from the river. One tank is as close as five miles to the river. Over the years, 70 of the tanks have leaked about 1 million gallons of waste into the soil. At least some of the leaked tank waste has reached the groundwater, which eventually flows into the Columbia River. Estimated time for the tank waste to reach the river is anywhere from seven to 20 years to a couple generations. How badly it damages the river depends on how much gets there and when.
K Basins: The two K Basins, only a quarter mile from the Columbia River, are huge indoor pools holding 2,300 tons of corroded, highly radioactive spent nuclear fuel under water. They have leaked in the past. An earthquake might crack them open, spilling radioactive water into the Columbia. Fuel exposed to the air could burn, scattering radioactive particles into the air. Because of the danger, the K Basins are considered one of Hanford's most urgent problems.
Photo by CH2M Hill-Hanford Group
The Teamwork of Sampling
It takes teamwork to remove and package equipment after sampling activities. Sampling is part of an ongoing program to characterize Hanford's tank waste.
In late 1997, DOE and its contractors discovered another problem with Tank SY-101: Its surface level was steadily rising. To investigate this phenomenon, a special project team was formed. The team determined that gas bubbles and waste particles were being trapped within a “waste crust,” causing it to grow.
The SY-101 project team was given clear direction on its scope of work. In the detailed planning, the technical baseline, resource-loaded schedule and the probability of success were all documented.
This exercise provided the credibility to secure the needed resources and helped to bond the project team. The team prepared an aggressive plan for a series of transfers and dilutions that received concurrence from DOE and an independent panel of experts from several universities and laboratories.
Photo by CH2M Hill-Hanford Group
Attention to detail is imperative as workers monitor the more than 8,000 instruments that collect data on environmental and worker safety.
The transfers began after training, calibration and readiness assessment activities were completed. While preparing for the transfers, the SY-101 project team also managed and mitigated the crust growth. This included putting additional controls on tank operation, deploying a mechanical arm to disturb the crust and release some of the trapped gas, and lancing the crust with a water spray to soften it before transfers. By identifying critical activities early and clearly communicating them to the entire project team in weekly meetings, team leaders successfully managed the work scope, cost, quality and personnel.
The DOE and CH2M Hill Hanford Group solved the SY-101 problems by diluting and transferring more than 520,000 gallons of waste from the tank and adding 434,000 gallons of dilution water in three operations between December 1999 and March 2000.
Once the top safety problem in the DOE complex, Tank SY-101 now is one of DOE's biggest environmental success stories, with the project completed 10 months ahead of schedule and a savings to taxpayers of more than $1 million. Taxpayers could save an additional $80 million over the lifetime of the tank when special tank controls are removed.
Inspiring Exceptional Performance
Truly inspired team members go above and beyond what is expected, often shortening project schedules and brainstorming innovative cost-saving solutions. The following tips, employed at CH2M Hanford Hill, will help project managers build a focused team:
Assume that people working on a project know more about how to do their job than you do. Listen to their ideas.
You have experience in what can go wrong: Offer your team your professional paranoia. While workers plan for project execution, project managers plan for contingencies.
If the team is doing a good, solid job, tell them so—often.
Don't delay in dealing with bad news—it won't improve tomorrow.
Make the tough decisions—they shouldn't be made by consensus or majority rule.
Find every way you can to communicate and be accessible—all-hands meetings, small group meetings (“Coffee with the President”), letters to the home office, walking the shop floor or halls, showing up for lower-level staff meetings, observing shift turnover, and answering your own mail and phone. The larger the team, the more difficult it becomes to motivate individuals.
When someone brings you a problem, ask for a solution. That person will almost always know better what needs to be done than you do.
Minimize the number of things that you define as really important.
Don't accept bad performance or mediocrity. At the first indication of poor performance, approach the person who is not performing well and speak in a factual, specific and unemotional way.
Fran DeLozier is president and general manager of CH2M Hill Hanford Group, the U.S. DOE prime contractor with responsibility for the storage and retrieval for treatment of radioactive waste at the Hanford site. She is a licensed professional engineer, with 28 years of experience in nuclear programs including operations, safety, engineering, and executive and project management.
PM Network July 2001