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By the end of FY 1986, 93 of the old tanks will be stabilized and 85 will be isolated. Due to a critical shortage of double-shell tank space, the Stabilization and Isolation Program is being performed at a minimal level. The rate is limited to pumping a total of 1 million gallons of liquid from the single-shell tanks until double-shell tanks are available in FY 1992. The Stabilization and Isolation Program is scheduled to be completed in FY 1994,

At Savannah River, the objective of the waste transfer program is to remove the waste from the 23 old high-level waste storage tanks and transfer it to new ones, and prepare feed for the Defense Waste Processing Facility vitrification and saltstone plants.

First priority is the removal of waste from the seven singleshell tanks. This will be completed in FY 1986. All the other tanks have secondary containment. Removal of waste from all the old tanks will be completed in FY 1994. Feed preparation is on schedule for saltstone startup in FY 1988, and vitrification startup in FY 1990.

At Idaho, there is no waste transfer program because liquid wastes are routinely calcined to a dry, granular solid and stored in underground bins.

High-Level Waste Tanks

Question: How many new tanks are funded at each site, what is the cost of each tank, and what is the requirement for new tanks beyond those funded to date?

Answer: High-level waste (HLW) is managed at Hanford, Idaho, and Savannah River.

At Hanford, funding for eight conventional double-shell HLW storage tanks under project 83-D-157 (AP tank farm) was completed in FY 1985. The total estimated cost (TEC) of this project was $49,155,000. Funding for four new aging waste (i.e., high heat HLW) storage tanks is requested in FY 1987 under project 87-D-174 (AQ tank farm). The TEC of this project if $57,300,000. Aging waste storage tanks cost more than conventional tanks because of the additional requirements for cooling, seismic and other criteria, and backup power supplies. The requirement for four additional conventional HLW storage tanks is considered for FY 1988. Methods to reduce the volume of waste generated are being evaluated. Assuming planned facilities are available to process and immobilize the waste stored in tanks, no new tanks should be required after the FY 1988 request.

At Idaho, the present tank inventory is considered to be adequate to meet future requirements because the backlog of liquid waste is routinely calcined to a dry, granular solid for storage in bins. New Calcined Solids Storage Facilities are required about every 3 to 4 years.

At Savannah River, no additional tanks will be required since the Defense Waste Processing Facility, to immobilize waste removed from tanks and prepare it for disposal in a repository, it is expected to be in operation in FY 1990.

Question: What problems do you still encounter with leaking Ianks at each site?

Answer: None of the tanks or calcined solids storage bins at Idaho or the new high-integrity double-shell tanks at Hanford or Savannah River has leaked.

Of the 149 old single-shell tanks at Hanford, 7 are classified as "assumed leakers." This is a conservative term which is defined as "a tank for which there is an indication of a breach of integrity. Such a tank exhibits surveillance parameter changes that exceed stated criteria limits and result in a less than 95 percent confidence that it is sound." of the remaining 142 old single-shell tanks, 49 are sound, deactivated tanks and 93 are classified as "stabilized," meaning that the pumpable liquid has been removed. Pumpable liquid is being removed from the old tanks and transferred to new high-integrity double-shell tanks as part of the Stabilization and Isolation program, which will complete all 149 old tanks 1994.

No significant amount of radioactive waste has been released to the environment from old waste tanks at Savannah River. There is, however, concern about leakage because of the age, condition, and design of the old waste tanks, which were built between 1952 and 1961. Of the 23 old waste tanks containing high-level waste, there are seven single-shell tanks, one of which has a crack in the wall above the liquid level. There has been a small amount of in-leakage of ground water through the crack. Sixteen of the old tanks are of "cup-and-saucer" design, which means that the tank sits in a 5-foot-high secondary containment. There has been leakage into the secondary containment in nine of these tanks. In one of the tanks, a leak of about 25 gallons did occur from the secondary containment to the surrounding soil in 1960. Thorough and continuing monitoring and tests have shown that the waste is confined to the immediate area of the tank. In all other cases, the waste has been collected from the secondary containment and returned to the tanks. Waste from the old tanks is being transferred to new high-integrity double-shell tanks as part of the tank replacement/waste transfer program, which will be completed in FY 1994.

DOE Waste Inventory

Question: Please provide a table listing the quantity and status of the various classes of nuclear waste at each site.

Answer: The Department manages three classes of nuclear waste at its sites: high-level waste (HLW), transuranic waste, and lowlevel waste.

High-level waste 18 stored in underground tanks at Hanford and Savannah River pending retrieval, immobilization in borosilicate

glass, and ultimate disposal in a geologic repository. The Defense Waste Processing Facility, for the immobilization of HLW, is now under construction and is scheduled to operate in FY 1990. A facility to immobilize waste at Hanford is expected to operate in FY 1996. At Idaho, newly generated HLW is temporarily stored in underground tanks. The HLW is then routinely converted to a dry granular solid called "calcine," which is stored in underground bins. This material will be eventually prepared for disposal in a geologic repository in early 2000.

Since 1970, transuranic waste (TRU) has been stored pending retrieval, processing if necessary, certification, transportation to, and emplacement in the Waste Isolation Pilot Plant (WIPP). In 1985, the Department began to certify TRU, as it was generated, to meet the waste acceptance criteria of the WIPP. This waste is stored separately from previously generated TRU. Prior to 1970, TRU was disposed of as low-level waste (LLW). This waste is monitored, and remedial actions will be taken if needed.

LLW is disposed of in near-surface trenches using shallow land burial, or in deeper trenches or holes using greater confinement disposal. In some cases, the disposal facilities are lined or otherwise engineered to assure isolation from the environment. The method of disposal depends on the characteristics of the waste.

The following table shows the volume of each class of nuclear waste at the Department's sites as of December 31, 1984. Additional information can be obtained from the Department's annual report entitled, "Spent Fuel and Radioactive Waste Inventories, Projections, and Characteristics," DOE/RW-0006, December 1985.

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*Volume in thousands of cubic meters as of December 31, 1984.

Idaho Calcined Solids Storage

Question: What is the plan to construct a vitrification facility at Richland and Idaho. Describe the status of construction of the Calcined Solids Storage at Idaho?

Answer: Under current planning assumption, the Hanford Waste Vitrification Plant (HWVP) will be constructed at Richland starting in FY 1989 and 18 expected to be in operation by FY 1996. It will perform the same function as the vitrification plant of the Defense Waste Processing Facility (DWPF), which is currently under construction and is expected to begin hot operation in FY 1990. Maximum benefit is being gained by technology transfer from DWPF to HWVP.

Waste at Idaho is stored in immobile form, calcine, in facilities with a design life of 500 years. After DWPF and HWVP are in operation, decisions will be made on the final disposition of the calcined waste in storage bins at Idaho.

Physical construction of the seventh set of solids storage bins is expected to begin in July 1986. The present status of the project is design 97 percent complete and procurement 13 percent complete.

Hanford Waste Disposal

Question: Please explain how the B-Plant facility would affect plans for waste disposal and the timetable for the vitrification facility at Hanford.

Answer: B-Plant is an essential facility to prepare Hanford defense waste for disposal. The waste consists of liquid, sludge, and salt cake and is stored in large underground tanks. B-Plant will be used to separate Hanford defense waste into two streams. One stream, comprising over 90 percent of the waste volume, will consist of a decontaminated salt solution which will qualify as low-level waste. It will be incorporated in grout and disposed of by shallow land burial on site. The other stream, while relatively small in volume, will contain over 99 percent of the radioactivity. It will be delivered to the vitrification facility and incorporated in glass for subsequent disposal in a Federal repository.

Hanford Waste Vitrification Plant

Question: Please provide the funding provided for the Hanford Waste Vitrification Plant, HWVP, for FY 1984, FY 1985, FY 1986, FY 1987 and describe the activities funded. How much is anticipated in FY 1988, FY 1989, and thru FY 1994?

Answer: The following table provides the funding by fiscal year ($ in millions).

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The activities funded are for process development, equipment development, and conceptual facility design. In the last 2 years, emphasis has been on technology transfer from the Defense Waste Processing Facility (DWPF) which is being built at Savannah River to perform a comparable function. DWPF is about 6 years ahead of HWVP 80 that vital experience is being obtained and incorporated in HWVP. Another important current activity is coordination with the Federal repository effort to assure acceptance of the HWVP product in the repository.

The following table provides the estimated funding for HWVP by fiscal year ($ in millions). These estimates are very tentative until conceptual design activities are complete.

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Question: What is the current plan for the initiation of construction for HWVP? (Include the estimated key dates and funding required over the construction period.)

Answer: The current plan is for a HWVP design-only project in FY 1988 and a construction project in FY 1989. The design-only project will provide for effort by the architect-engineer to refine the design and improve the cost estimate. The current estimated construction cost is $630 million. Key dates are:

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Question: How much funding is needed to complete pre-construction activities for HWVP and how quickly can pre-construction be completed with full funding in FY 1987?

Answer: The funding of $9.6 million is adequate for completion of conceptual design, which is a prerequisite for construction. Conceptual design is scheduled for completion in the first quarter of FY 1988 and could not be accelerated materially by additional funding.

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