Retrieval & Treatment of Hanford Tank Waste


Book Description

The Hanford Tank Farms contain 53 million gal of radioactive waste accumulated during over 50 years of operations. The waste is stored in 177 single-shell and double-shell tanks in the Hanford 200 Areas. The single-shell tanks were put into operation from the early 1940s through the 1960s with wastes received from several generations of processing facilities for the recovery of plutonium and uranium, and from laboratories and other ancillary facilities. The overall hanford Tank Farm system represents one of the largest nuclear legacies in the world driving towards completion of retrieval and treatment in 2028 and the associated closure activity completion by 2035. Remote operations, significant radiation/contamination levels, limited access, and old facilities are just some of the challenges faced by retrieval and treatment systems. These systems also need to be able to successfully remove 99% or more of the waste, and support waste treatment, and tank closure. The Tank Farm retrieval program has ramped up dramatically in the past three years with design, fabrication, installation, testing, and operations ongoing on over 20 of the 149 single-shell tanks. A variety of technologies are currently being pursued to retrieve different waste types, applications, and to help establish a baseline for recovery/operational efficiencies. The paper/presentation describes the current status of retrieval system design, fabrication, installation, testing, readiness, and operations, including: (1) Saltcake removal progress in Tanks S-102, S-109, and S-112 using saltcake dissolution, modified sluicing, and high pressure water lancing techniques; (2) Sludge vacuum retrieval experience from Tanks C-201, C-202, C-203, and C-204; (3) Modified sluicing experience in Tank C-103; (4) Progress on design and installation of the mobile retrieval system for sludge in potentially leaking single-shell tanks, particularly Tank C-101; and (5) Ongoing installation of various systems in the next generation of tanks to be retrieved.




Tank Waste Retrieval, Processing, and On-site Disposal at Three Department of Energy Sites


Book Description

DOE Tank Waste: How clean is clean enough? The U.S. Congress asked the National Academies to evaluate the Department of Energy's (DOE's) plans for cleaning up defense-related radioactive wastes stored in underground tanks at three sites: the Hanford Site in Washington State, the Savannah River Site in South Carolina, and the Idaho National Laboratory. DOE plans to remove the waste from the tanks, separate out high-level radioactive waste to be shipped to an off-site geological repository, and dispose of the remaining lower-activity waste onsite. The report concludes that DOE's overall plan is workable, but some important challenges must be overcomeâ€"including the removal of residual waste from some tanks, especially at Hanford and Savannah River. The report recommends that DOE pursue a more risk-informed, consistent, participatory, and transparent for making decisions about how much waste to retrieve from tanks and how much to dispose of onsite. The report offers several other detailed recommendations to improve the technical soundness of DOE's tank cleanup plans.




One System Integrated Project Team


Book Description

The One System Integrated Project Team (IPT) was formed in late 2011 as a way for improving the efficiency of delivery and treatment of highly radioactive waste stored in underground tanks at the U.S. Department of Energy's (DOE's) 586-square-mile Hanford Site in southeastern Washington State. The purpose of the One System IPT is to improve coordination and integration between the Hanford's Waste Treatment Plant (WTP) contractor and the Tank Operations Contractor (TOC). The vision statement is: One System is a WTP and TOC safety conscious team that, through integrated management and implementation of risk-informed decision and mission-based solutions, will enable the earliest start of safe and efficient treatment of Hanford's tank waste, to protect the Columbia River, environment and public. The IPT is a formal collaboration between Bechtel National, Inc. (BNI), which manages design and construction of the WTP for the U.S. Department of Energy's Office of River Protection (DOEORP), and Washington River Protection Solutions (WRPS), which manages the TOC for ORP. More than fifty-six (56) million gallons of highly radioactive liquid waste are stored in one hundred seventy-seven (177) aging, underground tanks. Most of Hanford's waste tanks - one hundred forty-nine (149) of them - are of an old single-shell tank (SST) design built between 1944 and 1964. More than sixty (60) of these tanks have leaked in the past, releasing an estimated one million gallons of waste into the soil and threatening the nearby Columbia River. There are another twenty-eight (28) new double-shelled tanks (DSTs), built from 1968 to 1986, that provide greater protection to the environment. In 1989, DOE, the U.S. Environmental Protection Agency (EPA), and the Washington State Department of Ecology (Ecology) signed a landmark agreement that required Hanford to comply with federal and state environmental standards. It also paved the way for agreements that set deadlines for retrieving the tank wastes and for building and operating the WTP. The tank wastes are the result of Hanford's nearly fifty (50) years of plutonium production. In the intervening years, waste characteristics have been increasingly better understood. However, waste characteristics that are uncertain and will remain as such represent a significant technical challenge in terms of retrieval, transport, and treatment, as well as for design and construction ofWTP. What also is clear is that the longer the waste remains in the tanks, the greater the risk to the environment and the people of the Pacific Northwest. The goal of both projects - tank operations and waste treatment - is to diminish the risks posed by the waste in the tanks at the earliest possible date. About two hundred (200) WTP and TOC employees comprise the IPT. Individual work groups within One System include Technical, Project Integration & Controls, Front-End Design & Project Definition, Commissioning, Nuclear Safety & Engineering Systems Integration, and Environmental Safety and Health and Quality Assurance (ESH & QA). Additional functions and team members will be added as the WTP approaches the operational phase. The team has undertaken several initiatives since its formation to collaborate on issues: (1) alternate scenarios for delivery of wastes from the tank farms to WTP; (2) improvements in managing Interface Control Documents; (3) coordination on various technical issues, including the Defense Nuclear Facilities Nuclear Safety Board's Recommendation 2010-2; (4) deployment of the SmartPlant Foundation-configuration Management System; and (5) preparation of the joint contract deliverable of the Operational Readiness Support Plan.










The Hanford Tanks


Book Description

The Hanford Site (also known as the Hanford Reservation) occupies approximately 1,450 km2 (560 square miles) along the Columbia River in south-central Washington, north of the city of Richland. The site was established by the federal government in 1943 to produce plutonium for nuclear weapons. Currently, the mission of the site, under the responsibility of the U.S. Department of Energy (DOE), is management of wastes generated by the weapons program and remediation of the environment contaminated by that waste. As part of that mission, DOE and the State of Washington Department of Ecology prepared the Hanford Site Tank Waste Remediation System Draft Environmental Impact Statement (DEIS). The Hanford Tanks is a general review of the DEIS. Its findings and recommendations are the subject of this report. Selection of a disposition plan for these wastes is a decision of national importance, involving potential environmental and health risks, technical challenges, and costs of tens to hundreds of billions of dollars. The last comprehensive analysis of these issues was completed 10 years ago, and several major changes in plans have occurred since. Therefore, the current reevaluation is timely and prudent. This report endorses the decision to prepare this new environmental impact statement, and in particular the decision to evaluate a wide range of alternatives not restricted to those encouraged by current regulatory policies.




TANK WASTE RETRIEVAL LESSONS LEARNED AT THE HANFORD SITE.


Book Description

One of the environmental remediation challenges facing the nation is the retrieval and permanent disposal of approximately 90 million gallons of radioactive waste stored in underground tanks at the US Department of Energy (DOE) facilities. The Hanford Site is located in southeastern Washington State and stores roughly 60% of this waste. An estimated 53 million gallons of high-level, transuranic, and low-level radioactive waste is stored underground in 149 single-shell tanks (SSTs) and 28 newer double-shell tanks (DSTs) at the Hanford Site. These SSTs range in size from 55,000 gallons to 1,000,000 gallon capacity. Approximately 30 million gallons of this waste is stored in SSTs. The SSTs were constructed between 1943 and 1964 and all have exceeded the nominal 20-year design life. Sixty-seven SSTs are known or suspected to have leaked an estimated 1,000,000 gallons of waste. The risk of additional SST leakage has been greatly reduced by removing more than 3 million gallons of interstitial liquids and supernatant and transferring the waste to the DST system since 1997 as part of the interim stabilization program. Retrieval of SST saltcake and sludge waste is underway to further reduce risks and stage feed materials for the Hanford Site Waste Treatment Plant. This paper presents lessons learned from retrieval of tank waste at the Hanford Site and discusses how this information is used to optimize retrieval system efficiency, improve overall cost effectiveness of retrieval operations, and ensure that HFFACO requirements are met.




Nuclear Waste


Book Description







HANFORD TANK WASTE TREATMENT SYSTEM.


Book Description

The US Department of Energy (DOE) is constructing the Hanford Waste Treatment Plant which is the largest waste pretreatment and vitrification facility in the world. This massive facility will begin commissioning operations in 2009, with full scale production beginning in 2011. While this facility will provide a much needed waste treatment capability to meet the department accelerated cleanup goals for closure of the Hanford waste tank systems, it alone will not provide enough capacity to complete the waste treatment mission by the 2028 regulatory milestone. The 53 million gallons of radioactive waste remaining in Hanford's 177 single-shell tanks (SST) and double-shell tanks (DST) present a broad range of radiochemical and chemical contents. The US Department of Energy, Office of River Protection (ORP) has established a strategy for waste retrieval and waste treatment that recognizes that all tank waste is not identical, and that other processes can be utilized to safely and economically treat tank waste for ultimate disposal. The ORP is pursuing a 3-tiered strategy to define, develop, and deploy treatment capability that will meet the 2028 waste treatment milestone. Ultimately, by tailoring the treatment process to the actual waste being processed, economies and efficiencies can be exploited to improve the overall treatment approach. In the end, DOE expects that each of the three elements will process waste as follows: (1) Transuranic (TRU) waste packaging and disposal will treat about 2 percent of the total waste sodium; (2) Supplemental treatment will account for about 47 percent of the low-activity waste (LAW) waste sodium; and (3) The Waste Treatment Plant will process about 53 percent of the LAW waste sodium and 100 percent of the high-level waste (HLW).