The Hanford Site is a U.S. Department of Energy (USDOE) owned, contractoroperated facility located in southeastern Washington State near Richland. The 586-square-mile Hanford Site was established during World War II and played a pivotal role in the nation's defense for more than 40 years. The Site was a plutonium production complex with nine nuclear reactors and associated processing facilities. Today, under the direction of USDOE, the Hanford Site is engaged in the world's largest environmental cleanup project. The Site also supports programs in science, technology and energy. After more than 40 years of nuclear materials production, approximately 53 million gallons of liquid waste remain stored in 177 underground storage tanks in Hanford’s tank farm system. Because some of the 149 single shell tanks have leaked in past years, all of the pumpable liquid in the tanks has been transferred to Hanford’s double shell tanks.  USDOE and Washington State Department of Ecology are expected to confirm that as much liquid as possible has been pumped and the project is completed. What remains in the tanks is a solid form, considered less of a threat to leak into the environment. Work is underway to begin retrieving these solids.

Closing the Tank Waste Storage System as directed by Congress, USDOE’s Office of River Protection (ORP) was established in 1998 to manage Hanford tank waste retrieval, treatment, and disposal.  The ORP mission is to retrieve 99% of the waste from the tanks, treat the waste through various treatment processes, dispose of the waste and close the Single Shell Tank (SST) system. This action, which is required to reduce risk to the environment and protect human health, complies with the Tri-Party Agreement signed by USDOE, the Washington Department of Ecology and the U.S. Environmental Protection Agency, and with other federal and state laws.  CH2M Hill Hanford Group is the ORP prime contractor responsible for retrieving the highly radioactive and hazardous waste. A treatment plant is being designed and built on the Hanford Site by Bechtel National, Inc. to process waste for long-term storage in a solid glass-like form. CH2M HILL is also responsible for storage of the treated waste until permanent disposal facilities become available. Closing the tank waste storage system involves first making decisions on which methods will be used to retrieve, treat and dispose of tank waste and close tank systems and associated facilities. ORP’s strategy for retrieving,  reating and disposing of the tank waste and closing the tank farms has continued to evolve based on information that has become available since the Tank Waste Remediation System (TWRS) Record of Decision was issued in 1997. New information and proposed changes include:

• Increasing the throughput capacity of the Waste Treatment Plant by increasing the capacity of the High-Level Waste melter at startup; and

• Treating and disposing of various waste streams based upon their characteristics.

For example some tanks may contain Transuranic (TRU) waste that could be appropriately disposed of at the Waste Isolation Pilot Plant in New Mexico.  TRU waste includes any waste contaminated with manmade radioactive elements heavier than uranium. Supplemental treatment technology also may be used to reduce risk more rapidly by accelerating waste solidification. There is currently sufficient knowledge to begin the process of developing tank farm closure plans under the State of Washington requirements. 

Role of the EIS in Analyzing Closure Options A draft Environmental Impact Statement (EIS) is being prepared as part of the National Environmental Policy Act (NEPA) process to examine the options for safely retrieving and treating radioactive, hazardous and mixed tank waste; closing the SST system; and storing and/or disposing of the waste generated from these activities at Hanford. These actions significantly reduce existing and potential future risk to site workers, the public and the environment. Milestones are set up in the Tri-Party Agreement.  The draft EIS is expected to be available for public review in October 2004 with a 60-day public comment period. After the draft is published ORP will hold a public workshop to provide information on the EIS. The Record of Decision is expected in 2005.

The draft EIS will examine treatment alternatives to be used in conjunction with vitrification in the Waste Treatment Plant. These options will add to those that were already evaluated in the earlier TWRS EIS in 1997. Tank waste treatment involves retrieving high level liquid tank waste and processing it for long-term storage in a solid glass-like form. The EIS will also analyze closure of 149 single shell tanks, 61 smaller miscellaneous underground storage tanks, associated piping and contaminated soil. It will also evaluate two closure barriers that could be placed over the top of the SST system when all of the retrieval and treatment activities are completed.

An EIS analysis by itself does not constitute a decision. Rather it is one of several sources of information that decision makers consider in making a decision on a proposed action. The final step in the NEPA process is issuing a Record of Decision (ROD) or a series of them on a proposed action to document decisions made by the agency. Decisions stated in an ROD, which are generally broad and programmatic, enable more detailed activities to move forward. These activities are then further defined in implementing documents, such as closure plans and permits.

The State of Washington is working with USDOE to review the Tank Closure EIS and to provide guidance and comment. Using the process granted to Ecology through the Revised Code of Washington and the Washington Administrative Code, Ecology may adopt the Final Tank Closure EIS, satisfying State Environmental Policy Act requirements to evaluate significant impacts to the environment and human health. Adoption of the Tank Closure EIS will assist Ecology in issuing the dangerous waste permits necessary to close the SST’s.

Single Shell Tank Waste Retrieval Underway Retrieval of solids and sludges in the SST’s has now been initiated. On December 31, 2003 CH2M Hill Hanford Group, the Tank Closure contractor, submitted a letter to ORP stating that retrieval operations had been completed on C-106, the first of the 149 SST’s.

Retrieval of tank waste from Tank S-112 now underway is scheduled to be completed by the end of September. Each of the 149 SST’s contains a unique composition of waste. Some waste is in the form of salt cake, a crystalline material, while other tanks contain sludge, waste of a peanut butter consistency. Therefore, the same retrieval system cannot be used for all of the tanks.

C-106 and S-112 used a system called Modified Sluicing, which is particularly effective for salt cake type waste. Sluicing requires use of a high-pressure water nozzle that is directed at the waste to dissolve it and suspend the solid particles in the solution. The solution can then be pumped out, taking the solids with it. C-106 was unique in that after much of the solid waste was removed, what was left did not dissolve readily in the water. Adding several batches of oxalic acid was effective in dissolving the solids so that much of the remaining waste could be retrieved.

The C-200 series tanks, four 55,000-gallon tanks, will be retrieved by September. A system called Vacuum Retrieval will be used in these tanks. This system uses a high-powered vacuum that is inserted into the waste to suck out the material. The vacuum is on the end of an arm that can rotate around the tank to reach different locations inside the tank. A water nozzle is also used to help direct some of the waste to the vacuum nozzle.

A third type of retrieval is planned for some of the tanks that contain waste that may not be effectively moved around by water pressure. The Mobile Retrieval System features an apparatus like a small bulldozer that can push waste to the vacuum nozzle. Each of the retrieval systems has been tested at the Cold Test Facility and is being deployed for the first time. What is learned from each application will be applied to future retrievals. S-102 retrieval is expected to be completed before the end of 2004.

The U-200 series of tanks, four 55,000-gallon tanks, are scheduled for initiation of retrieval in early 2005.

Hanford Communities Position Hanford Communities support the approach in the Tri-Party Agreement for closing tanks and are encouraged by progress that has been made by USDOE and the Washington Department of Ecology.

To find out how you can become more involved in this important regional issue, or to have a Hanford Communities speaker talk to your organization, contact the Hanford Communities at (509) 942-7348 or by fax at (509) 942-7379.