Cleaning Up Sites Contaminated with Radioactive Materials: International Workshop Proceedings (2009)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

19 The Past, Present, and Future of the Facilities at Andreev Bay A. P. Vasiliev, International Center for Environmental Safety, Russian Federal Atomic Energy Agency (Rosatom) INTRODUCTION The Andreev Bay facilities were built in the late 1950s and early 1960s for the purposes of (1) nuclear submarine reactor refueling, (2) interim storage of spent nuclear fuel before its shipment to Mayak, (3) storage of solid radioactive waste from the Northern Fleet, and (4) treatment of liquid radioactive waste generated during facility operations. Thus, great quantities of spent fuel and radioactive waste were accumulated on the site during the more than 40 years of its operations. The spent fuel and radioactive waste storage facilities were never repaired, and today they are in very bad or even dangerous condition, presenting a serious radiation hazard to personnel and the environment. Some structures have become unsound, and radioactive substances escape with groundwater to the surrounding land and into Andreev Bay (see Figure 19-1). In May 1998 the government of Russia issued a decree instructing the Ministry of Atomic Energy (formerly Minatom, now the Russian Federal Atomic Energy Agency [Rosatom])   Vasiliev, A. P., V. A. Mazokin, M. E. Netecha, Yu. V. Orlov, and V. A. Shishkin. 2001. Radiation inheritance of Russian nuclear fleet and ecological safety problems relating to utilization of nuclear submarines and rehabilitation of other facilities in the Navy. Pp. 43-46 in Institution of Mechanical Engineers Conference Transactions, Radioactive Waste Management 2000: Challenges, Solutions, and Opportunities. London: Professional Engineering Publishing. 127 

128 CLEANING UP SITES CONTAMINATED WITH RADIOACTIVE MATERIALS FIGURE 19-1  Main potentially hazardous nuclear and radiation facilities at Andreev Bay. Fig 19-1.eps NOTE: 1—liquid waste processing building (structure 1); 2—spent fuel dry storage units bitmap (vessels 2A, 2B, 3A); 3—former spent fuel storage facility (building 5); 4—radioactive waste storage facility (building 6); 5—solid radioactive waste storage facility (7, 7A, 7B, 7B1, 7G, 7D, 67, 67A), open sites (7V, 7E, collector pipes); 6—stationary dock (structure 32). to resolve the problems associated with nuclear submarine decommissioning and remediation of the former coastal bases, which came to be referred to as tempo- rary spent fuel and radioactive waste storage sites. PRESENT CONDITION OF THE INFRASTRUCTURE, SPENT FUEL, AND RADIOACTIVE WASTES Minatom inherited a troublesome legacy. Practically the entire infrastruc- ture at the facilities was destroyed, including the heat, water, power supply, and sewage systems. Most facilities intended for spent fuel and radioactive waste storage had suffered operational damage and were not being used for their des- ignated purposes. The old and new spent fuel storage facilities were particularly dangerous. 

PAST, PRESENT, AND FUTURE 129 Building 5, with two 300 m3 spent fuel storage pools, began operating in 1962. In 1973 an annex with two 600 m2 pools was added (see Figure 19-2). In February 1982 a water level decrease was noticed in one of the pools, which suggested leakage. The same problem appeared later in the second pool. Ice formed by water leaking from the pools appeared on the outer surface of the building wall. It permeated the wall and the foundation, and the outdoor back- ground radiation level reached about 10 mSv per hour. To prevent personnel ex- posure, the wall at the leakage site was banked on the outside with a deep layer of soil. Radioactive water from the pools seeped into the ground under the building and reached an underground stream that outcropped about 20 m downhill from the building and then flowed into the bay. Later on, work was carried out under a contract with Norway to divert the stream from the building area, but most of the land near its former channel remained heavily contaminated. Attempts to locate and stop the leaks failed, and a decision was made to take urgent steps for providing temporary storage for all fuel kept in Building 5. Plans called for using three 1,000 m3 reinforced concrete tanks embedded to a depth of 5 m. Metal tubes 250, 275, and 300 mm in diameter were installed in the tanks, and the space between them was filled with concrete. The tube spacing was designed so the system would remain strongly subcritical even if an accident were to flood the tubes. Fuel retrieval from the damaged storage facility of Building 5 was by no means an easy job, but ingenious and dedicated naval personnel succeeded in moving all the canisters from Building 5 to the dry storage units (DSUs), with FIGURE 19-2  Building 5 configuration. NOTE: 1—process hall; 2—radiation-monitoring point; 3—transport corridor; 4—small Figure 19-2.eps cooling pools; 5—large cooling pools; 6—chain storage room. Bitmap image - Low resolution 

130 CLEANING UP SITES CONTAMINATED WITH RADIOACTIVE MATERIALS some fuel being taken to Mayak. Arranging spent fuel shipments from the site was significantly slower than unloading the submarines, and all three units were quickly filled. The DSUs and the old-design casks accommodated the fuel un- loaded from about 100 submarine and icebreaker reactors. Three open pads and seven storage facilities are in use for storing solid radioactive waste. The facilities have been in operation for more than 35 years and are no longer leak-tight. The exact quantities, composition, condition, and characteristics of the solid waste, especially those stored in subsurface facilities, are unknown. Liquid radioactive waste is kept in reinforced concrete tanks lined with stain- less steel. Their service time expired long ago; three tanks are no longer leak-tight and are exposed to groundwater penetration. Besides these tanks, liquid waste is also found in the cells of DSUs, as well as in the subsurface solid radioactive waste storage facilities. Since 2001, substantial work has been carried out to improve the radiation and environmental conditions. Large equipment and transport vehicles (handling equipment, service vessels, and trucks) were dismantled and removed from the land and water areas. The contaminated fragments were placed in temporary packaging and then stored. To improve working conditions, top priority infrastructure components were provided, such as a changing room, mobile checking and cleaning stations, a decontamination pad, a laboratory, an administrative building with amenities, and an upgraded main water conduit. Examination of the interim storage site began when it was handed over to Minatom. Information about the main hazards, their locations, activity levels, and conditions is essential for assessing the status of the site and the surrounding environment. The results of these studies served as input data for justification of the investments and decisions on the design details. Work at Andreev Bay is proceeding in three major directions, with the funds provided by Norway, Sweden, and the United Kingdom, respectively. Some in- vestigations in all the target areas are financed by Rosatom. Norway is financing the ground surveys, including studies on the radioactivity distribution in soil pro- files and in groundwater, as well as supporting the infrastructure restoration.  Based on the results of studies carried out by Russian specialists from the N. A. Dollezhal Research and Development Institute of Power Engineering (NI- KIET) from 2002 to 2005, radiation-contaminated areas were mapped, territorial zoning was performed to establish controlled access areas, and decontamination   Akhunov, V. D. 2001. High priority projects: Current status of organization and implementation. Presentation made at the Thirteenth Meeting of the International Atomic Energy Agency (IAEA) Contact Experts Group, Oskarshamn, Sweden, November 6-8, 2001.   Panteleev, V. N. 2006. Work performed in 2002-2005 under contracts with the Kingdom of Norway. Voprosy Utilizatsii APL [Issues in Decommissioning Nuclear-Powered Submarines] 2(10):52-57. 

PAST, PRESENT, AND FUTURE 131 plans were made and partly implemented in some hot spots (near the new pier). The work yet to be done involves a comprehensive survey of about 60 percent of the territory, including in-depth exploration of the soil in the area downstream from Building 5, a potential contamination source of the seawater and bottom sediments. Measurements of specific soil activity are tracked by cesium-137 baseline data (with the measured maximum reaching 9 × 106 Bq/kg) and strontium-90 data (4 × 106 Bq/kg). Gamma dose rates near the points with such activity reach 450 µSv per hour and are as high as 1,000 µSv per hour at the old pier. Surveys of the liquid radioactive waste storage facilities and open solid ra- dioactive waste storage sites, as well as a feasibility study on radioactive waste management, were carried out under a contract with Sweden. The solid waste storage facilities, where highly radioactive materials are expected to be found and groundwater presence is a strong probability, have not yet been explored. An inventory of the solid radioactive waste stored in open sites drastically contrasted with previous information about its quantity, with the new data indi- cating the presence of several times greater amounts of such waste. In addition, gamma background measurements taken at different points on the surface of casks showed large variations (a factor of several tens). This points to consider- able nonuniform activity distribution inside the casks and suggests the presence of individual radiation sources. This discovery calls for additional precautions to reduce personnel exposure risk during unloading of the casks. Radiation distribution on the solid waste storage pads has a highly irregular pattern. For instance, the gamma background at Buildings 7 and 7A is 1,000- 3,000 µSv per hour, with the beta contamination of the soil coming to 4,000- 6,000 particles per square centimeter per minute. The gamma background here is determined not by the soil contamination but by the radiation from one or possibly two casks placed on the roof of Building 7A. In most other places where solid waste is stored openly, the governing factor is soil contamination. As suggested by experience, the gamma background level may rise sharply after removal of some casks or concrete plates from the ground surface, with loss of the shielding they provided. This should be taken into account in planning op- erations. The main radionuclides are cesium-137 and strontium-90, but in some places the cobalt-60 contribution may approach 10 percent. Practically no alpha emitters have been discovered. The spent nuclear fuel storage facilities (DSUs and Building 5) are being surveyed under contracts funded by the United Kingdom. The first exploration   Izmailov, D. M., A. P. Vasiliev, and S. M. Kapinos. 2006. Radioactive waste handling on the An- dreev Bay site. Voprosy Utilizatsii APL 2(10):80-85.   Field, D., and V. Aden. 2003. Progress in the SNF management project. Presentation made at the Sixteenth Meeting of the IAEA Contact Experts Group, The Hague, The Netherlands, April 23-25, 2003. 

132 CLEANING UP SITES CONTAMINATED WITH RADIOACTIVE MATERIALS of Building 5 was not undertaken until more than 12 years after it closed. The inspection covered the process hall, the pools, and the chain storage room. Based on the information obtained, a program for comprehensive engineering and ra- diological survey (CERS) was prepared and carried out in 2005. The main tasks associated with the CERS of Building 5 include the following: • High gamma background in the chain room (0.3-1.0 µSv per hour) and possible collapse of the piled-up chains dropped from the process hall (pile height approximately 16 m; base area approximately 10 m2) • Very high gamma background in the process hall: up to 9.5 mSv per hour above the cantilever beams of the pools, approximately 100 mSv per hour on the bottom of the pools, and up to 600 mSv per hour at individual points; specific activity of samples taken in the hall as high as 1.2 × 109 Bq/kg (for cesium-137); a thick layer of dust on the passage floor and concrete plates • Cluttered space in the passages and above the pools, which adds to the risk of the piled-up concrete plates and beams collapsing into the deep (6.5 m) pools Still more dangerous are the conditions in the DSUs. Some cells are filled with water, with activity varying widely from 10–7 to 10–2 Ci/L. In 2004, NI- KIET specialists took the first samples of water at different depths. The activity increases with depth several times for cesium-137 and tens or hundreds of times for strontium-90. Alpha emitters are definitely present. For instance, at the bot- tom of one cell, the activity is 8.9 × 107 Bq/L for cesium-137, 7.2 × 108 Bq/L for strontium-90, and 5.4 × 104 for alpha emitters. This suggests that fuel is exposed to water and that the latter is picking up not only fission products but also ac- tinides. The spent fuel degradation is promoted by the high content of salts (up to 1,500 mg/L), including chlorides (up to 400 mg/L). Studies of corrosion processes conducted at Russian research institutions have pointed to the possibility of spent fuel degradation and disintegration into fragments of approximately 200 µm, which may stay inside the cask, forming a uranium-water mixture with a small proportion of the latter. In this case, the distribution coefficient (Keff) for one cask is much less than 1.0. To rule out the possibility of a chain reaction, the following procedure for spent fuel retrieval from DSU cells was adopted: • Drainage of the cells by pumping • Reloading of spent fuel assemblies into new canisters with the help of a standard transfer cask or using a retrieval machine that is being developed The loaded canisters will be put into TK-18 shipping casks, placed on a buf- fer pad, and then carried by a special vessel either to Murmansk or to Severod- vinsk for subsequent shipment to Mayak. 

PAST, PRESENT, AND FUTURE 133 Construction of an oil terminal in the Kola Gulf near Murmansk will increase the traffic of large oil tankers. It appears advisable, therefore, that spent fuel should be taken from Andreev Bay to Severodvinsk, where a spent fuel transfer point has been set up with U.S. assistance. However, in considering this option, we should remember that spent fuel shipment from Severodvinsk is problematic today, as the bridge across the mouth of the Nikolskoye River does not meet regulatory requirements. A new railway bridge must be built, and the need for such a bridge was justified in the Strategic Master Plan. At Andreev Bay, spent nuclear fuel is found not only in DSU cells but also in old-design casks, which were kept for a long time on an open pad. Today the condition of the fuel inside the casks is unknown. REMEDIATION OF THE TEMPORARY STORAGE SITE AND REDUCTION OF RADIATION RISKS The remediation of the temporary storage site and reduction of the radiation risks are already in progress. The following activities are supported by funds provided by the United Kingdom and Norway. • The road to the interim storage site has been repaired, the administra- tion building with amenities has been constructed, and the infrastructure is being restored. • The physical protection system is being set up. • Plans have been made to install the radiation-monitoring system. • Two mobile checking and cleaning stations and the required dosimetry equipment have been delivered and placed in service, and a radiochemical labora- tory has been set up. • Surveys of the grounds, buildings, and structures are being carried out. • A cost-benefit analysis has been prepared for building the spent fuel and radioactive waste handling infrastructure. • The technical and safety aspects of spent fuel handling options are being studied as a basis for final selection. The main problem is moving the spent fuel from Andreev Bay to Mayak, which is essential for nuclear safety reasons. For this to be achieved, the follow- ing should be developed and implemented for spent fuel handling: • A handling and transportation process, including the equipment required for unloading spent fuel canisters from DSU cells and casks of types 6 and 11   Sarkisov, A., ed. 2004. Strategic Approaches in Solving Decommissioning Problems of Retired Russian Nuclear Fleet in the Northwest Region. Moscow: Russian Academy of Sciences Nuclear Safety Institute. 

134 CLEANING UP SITES CONTAMINATED WITH RADIOACTIVE MATERIALS • Technology for handling damaged spent fuel, which is currently esti- mated at no less that 20 percent of the total, with this percentage expected to increase as the fuel remains in cells filled with water of high salt content • Safe working conditions at all stages of the operations At all stages, spent fuel handling gives rise to liquid and solid radioactive waste, including high-level waste. The latter will have to be treated in addition to the already existing solid and liquid waste. This means that modern facilities for handling not only spent nuclear fuel but also radioactive waste should be pro- vided on the Andreev Bay site. It is also necessary to provide temporary storage facilities, including a buffer pad for containerized spent fuel storage before it may be loaded on a vessel, as there are no alternative ways to remove the fuel from Andreev Bay, and a place where solid radioactive waste may be stored before it is shipped away to be buried or disposed of in a regional radioactive waste reposi- tory. However, neither the site nor the type of regional repository has yet been chosen. This is still another problem that should be resolved soon. THE FUTURE OF ANDREEV BAY The future of Andreev Bay is closely related to its past, although the site will not be used for its previous purpose. Nor does it have any apparent prospects for other uses. In the next 10 to 15 years at least, the activities on the site will include spent fuel conditioning and shipment, radioactive waste conditioning, demolition of contaminated buildings and structures, and remediation of the land and water areas. Arrangement of these activities is shown graphically in Figure 19-3. The cost and timescale of the remediation activities and the waste quantities to be shipped away for storage or disposal depend on the criteria underlying the end-state requirements that will be set for the grounds and structures at Andreev Bay. Considering that people are not expected to live in the area or even stay there for extended periods, “green field” status is not an objective. ”Brown field” status is quite appropriate under the circumstances (see Figure 19-3). It is suit- able for the arrangement of temporary solid waste storage before this waste is sent to the regional repository. Of course, this option should be justified in terms of environmental safety and economic efficiency following current regulatory requirements and should have the consent of the public and the authorities of neighboring towns and the entire region, as well as of the donor countries in- volved in activities at Andreev Bay. Relevant criteria and supplements to current regulations should also be de- veloped and approved in the next few years because of their great influence on the choice of technologies and the scope of work. One example may be given as an illustration: Some European countries, such as France and Sweden, have introduced the category of very low-level waste (VLLW) (0.3 to 100 Bq/g). A simplified cost-saving disposal procedure has been developed for such waste, 

FIGURE 19-3  Work stages in remediation of the Andreev Bay site. Figure 19-3.eps NOTE: SNF—spent nuclear fuel; RW—radioactive waste; CERS—comprehensive engineering and radiological survey; OBIN—cost-benefit analysis. Bitmap Image - Low resolution 135 Broadside 

136 CLEANING UP SITES CONTAMINATED WITH RADIOACTIVE MATERIALS with the associated safety concerns relating to the impacts on humans and the environment. The bulk of the radioactive waste found on the Andreev Bay site—primarily structural components and soil—belongs to this category. These materials need not be shipped away or containerized. It is simpler and cheaper to put them into surface storage facilities at the same site in keeping with rules and regulations that should be developed, validated, approved by the regulatory authorities, and accepted by the public and nongovernmental environmental organizations. A proposal for introducing in Russia a waste category similar to the Euro- pean VLLW was developed within the framework of Strategic Study No. 8 (in accordance with the Strategic Master Plan) in cooperation with representatives of the regulatory authorities. The condition of Andreev Bay today is a legacy of the Cold War. Remedia- tion of the site may be successfully accomplished through joint efforts by Russia and European countries, from a mutual willingness and ability to live in peace.